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Zhou, Guanyu, Zhao, Kejia, Luo, Hao, Ku, Yin, Peng, Haoning, Li, Shasha, Zhou, Wenjing, Luo, Nanzhi, Liu, Lunxu, Chen, Yaohui, (2026). LPIN2 contributes to tyrosine kinase inhibitor resistance via activation of PI3K pathway Translational Lung Cancer Research 15, 167
Background: Acquired resistance to tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) is a critical clinical barrier. While metabolic reprogramming is implicated in target-independent resistance, the specific role of triglyceride (TG) synthesis remains unclear. Objective: This study aims to systematically elucidate the precise role and underlying mechanisms of LPIN2-mediated lipid metabolic reprogramming in TKI resistance, and to explore potential metabolic-targeted combination therapies for NSCLC. Methods: Osimertinib-resistant (PC-9 OR) and alectinib-resistant (NCI-H3122 ALR) cell lines were established via a dose-escalation strategy. The resistant cells were then compared with their original sensitive cells under both drug-present and drug-withdrawn conditions. Metabolomic liquid chromatography-mass spectrometry (LC-MS) and transcriptomic analyses revealed shared differential features, which were selected as candidate key metabolic enzymes in TKI resistance. From this pathway, LPIN2 was selected as a consistently upregulated key enzyme for validation. The LPIN2 gene was knocked out using CRISPR/Cas9 technology; a series of functional assays (e.g., drug sensitivity, colony formation), complemented by lipid supplementation, pathway inhibition (PI3K/mTOR), and a mouse xenograft model to verify the underlying mechanism. Results: LPIN2 was identified as a key driver of TKI resistance in NSCLC, with its mRNA and protein levels significantly upregulated (~2-fold) in osimertinib-resistant (PC-9 OR) and alectinib-resistant (NCI-H3122 ALR) cells. CRISPR/Cas9-mediated LPIN2 knockout restored TKI sensitivity, displaying oncogene-specific magnitudes of reduction in the half-maximal inhibitory concentration (IC50): decreasing from 3,585 nM to 229-477 nM in EGFR-mutant PC-9 OR cells, and exhibiting a more moderate reduction from 2,264 nM to 325-488 nM in ALK-fusion NCI-H3122 ALR cells, while suppressing tumor growth in vivo (Ki67 downregulation). Mechanistically, LPIN2 promoted TG accumulation and lipid droplet deposition; exogenous TG supplementation (1,2-dioleoyl-3-arachidoyl-sn-glycerol) induced TKI resistance in parental cells and rescued drug tolerance in LPIN2-knockout cells, whereas inhibition of downstream TG synthesis enzymes [diacylglycerol O-acyltransferase1/2 (DGAT1/2)] recapitulated the knockout phenotype. Furthermore, perturbation of the LPIN2-TG axis was associated with modulation of the PI3K-AKT-mTOR survival pathway, regulating apoptosis-related proteins (BCL-XL/BCL2 downregulation, BAX upregulation). Combined treatment with osimertinib and a PI3K inhibitor (Wortmannin) synergistically suppressed tumor growth and prolonged survival in xenograft models. Conclusions: LPIN2 contributes to TKI resistance in NSCLC through a novel LPIN2-TG metabolic node that is functionally associated with PI3K-AKT signaling: it enhances TG biosynthesis and lipid droplet accumulation, thereby indirectly modulating the PI3K-AKT pathway to inhibit apoptosis. Targeting this axis reverses TKI resistance in vitro and in vivo, identifying LPIN2 as a drug stress-independent resistance driver and potential biomarker for metabolic-targeted combination therapy.
JTD Keywords: Acquired-resistance, Cell lung-cancer, Driven, Fatty-acids, Lpin2, Metabolism, Non-small cell lung cancer (nsclc), Triglyceride metabolism (tg metabolism), Tyrosine kinase inhibitor resistance (tki resistance)
Diaz-Fernandez, Sergio, Aleluia, Matilde, Saraiva, Margarida, Soldevilla, Pablo, Torrelles, Jordi B, Sharan, Riti, Verreck, Frank A W, Izzo, Angelo, Vidal, Maria, Moreira, Ana C, Perez de Val, Bernat, Roca, Francisco Jose, Preda, Madalina, Torrents, Eduard, Julian, Esther, Dominguez, Jose, Latorre, Irene, (2026). The study of immunological markers in tuberculosis across animal models and its translation to human research LAB ANIMAL 55, 248-266
Tuberculosis (TB), a disease caused by Mycobacterium tuberculosis, remains one of the major causes of death from infection worldwide, with over a million associated deaths each year. The study of biomarkers for TB is critical for advancing our understanding and management of the disease. Biomarkers, defined as measurable indicators of biological states or conditions, are invaluable for the diagnosis, prognosis and treatment monitoring of TB. Clinical studies have provided critical knowledge on the matter but are also notoriously constrained by economical, ethical and sampling limitations. The use of animal models provides a simpler, more controllable, cost-effective setting with great potential for translation to humans. They also allow the evaluation of biomarkers within the respiratory compartment, when available, which is of particular interest due to the nature of TB pathogenesis. This Review focuses on the current landscape of TB biomarker discovery in several animal models, from invertebrates to large mammals. Here we summarize the basics of host-pathogen immune interaction, describe the main methodological approaches used and highlight the most substantial findings for each animal model studied. Furthermore, we discuss the advantages, challenges and limitations associated with species-specific differences in animal models. We conclude that integrating the data obtained from animal models and human studies is absolutely required to advance the TB field to accelerate the management of this disease.
JTD Keywords: Cd4 t-cells, Drosophila-melanogaster, Experimental airborne tuberculosis, Gamma release assay, Guinea-pig, Host-parasite relationships, Ifn-gamma, Mycobacterium-tuberculosis, Nitric-oxide synthase, Pulmonary tuberculosis
Lu, Guolan, Hickey, John W, Haist, Maximilian, Qin, Xulei, Zhao, Emily, Naveed, Abdullah, Forgo, Erna, Baertsch, Marc-A, Mani, Lucas, Rovira-Clave, Xavier, Finegersh, Andrey, Goltsev, Yury, Caraccio, Chiara, van den Berg, Nynke S, Hom, Marisa, Colburg, Deana R, Martin, Brock A, Kong, Christina S, Lui, Natalie S, Fisher, George A, Colevas, A Dimitrios, West, Robert B, Thurber, Greg M, Poultsides, George A, Nolan, Garry P, Rosenthal, Eben L, (2026). Single-cell spatial pharmacobiology identifies conserved stromal barriers to therapeutic antibody delivery in human solid tumors NATURE BIOTECHNOLOGY ,
The development of effective antibody therapeutics has been hampered by a lack of methods to measure drug delivery and activity within tumors at single-cell resolution. Here we introduce single-cell spatial pharmacobiology (SSP), an experimental and analytical framework that integrates in situ imaging of a systemically infused, fluorescently labeled therapeutic antibody with high-plex spatial proteomics to quantify antibody distribution, target engagement and tumor microenvironment (TME) architecture. We applied SSP to tumor tissues from participants with head and neck squamous cell carcinoma and pancreatic ductal adenocarcinoma who received the antibody panitumumab-IRDye800 in phase 1 trials. SSP identified pronounced spatial heterogeneity in single-cell drug delivery and target engagement, shaped by conserved stromal barriers, including periostin-rich extracellular matrix assemblies and fibroblast-activation-protein-positive cancer-associated fibroblast neighborhoods, which were associated with reduced antibody delivery in both tumor types. SSP measures drug-target-TME interactions in human tumors and can support studies of resistance mechanisms, dosing strategies and discovery of spatial biomarkers for precision oncology.
JTD Keywords: Cancer, Diffusion, Fibroblasts, Gemcitabine, Head, Inhibitor, Monoclonal-antibodies, Multiplex, Panitumumab-irdye800cw, Transport
Gomez-Valades, Alicia G, Meseguer, David, Varela, Luis, Lienhard, Gabriele, Fernandez, Uxia, Vidal-Itriago, Andres, Toledo, Miriam, Eyre, Elena, Laudo, Berta, Diaz-Castro, Francisco, Pozo, Macarena, Boutagouga Boudjadja, Mehdi, Fos-Domenech, Julia, Garcia-Ramon, Pau, Ferreira, Mariana, Altirriba, Jordi, Beiroa, Daniel, Chen, Bandy, Rodriguez-Diaz, Amanda, Mila-Guasch, Maria, Chivite, Inigo, Obri, Arnaud, Ramirez, Sara, Haddad-Tovolli, Roberta, Tahiri, Iasim, Gentry, Mathew S, D'Agostino, Giuseppe, Nogueiras, Ruben, Renier, Nicolas, Horvath, Tamas L, Guinovart, Joan J, Duran, Jordi, Schneeberger, Marc, Claret, Marc, (2026). Glycogen drives the sensory activation of POMC neurons Nature Metabolism 8, 1305-1329
Hypothalamic POMC neurons modulate systemic energy balance and glucose homeostasis by sensing nutritional state signals. In addition to this classic regulatory mode, these neurons are also activated by the sensory perception of food. Here, we report that food-related sensory cues engage glycogen metabolism in POMC neurons. Genetic depletion of glycogen through various approaches renders POMC neurons unresponsive to food-associated sensory stimuli. This defective perception of food is linked to alterations in consummatory behaviour, hepatic adaptations and cephalic insulin release associated with a prediabetic phenotype that progresses into overweight and overt diabetes with a high-calorie diet or ageing. Collectively, our results posit glycogen as a decisive fuel resource for meeting the rapid and demanding energy requirements linked with sensory activation. Furthermore, our data delineate the biological function of food perception and provide support for the physiological relevance of neuronal glycogen.
JTD Keywords: Accumulation, Agrp neurons, Cephalic phase responses, Circuits, Gene, In-vivo, Memory, Mitochondrial dynamics, Plasticity, Reveals
Cabrerizo-Aguado, Daniel, Barbugian, Federica, Ginebra, Maria-Pau, Wang, Xinru, Baker, David, Manero, Jose Maria, Guillem-Marti, Jordi, (2026). Antibacterial and cell-instructive chitosan/NeoNectin hydrogels crosslinked via click chemistry enable osteogenic differentiation within ultra-soft matrices CARBOHYDRATE POLYMERS 385, 125392
Hydrogels are attractive scaffolds for regenerative medicine, yet few systems combine robust mechanical performance, antimicrobial functionality, and controlled bioactivity. Here, we engineered chitosan-based hydrogels crosslinked via strain-promoted azide-alkyne cycloaddition (SPAAC) using 4-arm PEG-DBCO and functionalized with NeoNectin, a de novo-designed protein exhibiting subnanomolar affinity and high specificity for integrin alpha 5 beta 1. Rheological analysis confirmed stable hydrogel formation with an elastic modulus of similar to 0.1 kPa, within the physiological range of bone marrow and typically associated with maintenance of mesenchymal stem cells (MSCs) in an undifferentiated state, enabling evaluation of integrin-specific biochemical cues in an inhibitory mechanical environment. Antimicrobial assays confirmed intrinsic bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa, mitigating infection risks associated with implantation. Encapsulated human MSCs maintained high viability across all groups, validating cytocompatibility of the SPAAC crosslinking. Importantly, only covalently immobilized NeoNectin promoted sustained proliferation, increased expression of osteogenic genes, and significantly enhanced alkaline phosphatase activity, despite the low stiffness of the hydrogel matrix. These findings demonstrate that alpha 5 beta 1-specific signaling can override mechanical cues and drive osteogenic differentiation within ultra-soft environments. Overall, NeoNectin-functionalized SPAAC hydrogels provide a multifunctional platform that integrates antimicrobial properties, mechanical stability, and cellinstructive signaling for bone regeneration and broader tissue engineering applications.
JTD Keywords: Binding, Chitosan, Controlled-release, De novo protein design, Films, Hydrogel, In-vivo, Ir, Peg, Spaac reaction
Viteri, Angel, Vargas-Estevez, Carolina, Colombi, Samuele, Resina, Leonor, Tan, Huan, Sort, Jordi, Ginebra, Maria-Pau, Engel, Elisabeth, Aleman, Carlos, Garcia-Torres, Jose, (2026). Three-Dimensional Magnetoelectric Nanocomposite GelMA Hydrogels for Wireless Electrical Stimulation of Cardiac Cells ACS Applied Materials & Interfaces 18, 28020-28032
Bioelectrical cues are essential for cardiac function and regeneration, yet current electrostimulation strategies rely on invasive electrodes that limit spatial control and clinical translation. Here, we report magnetoelectric nanocomposite hydrogels that combine core-shell CoFe2O4@BiFeO3 magnetoelectric nanoparticles (ME NPs) with a photo-cross-linked methacrylated gelatin (GelMA) network, enabling wireless electroactivity through externally applied magnetic fields within a soft, biomimetic three-dimensional scaffold. Structural and physicochemical analyses confirmed the successful synthesis of crystalline core-shell ME NPs with strong interfacial coupling, as demonstrated by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and magnetic hysteresis measurements showing exchange bias effects. Homogeneous incorporation of ME NPs within GelMA produced highly porous and interconnected hydrogels, as revealed by scanning electron microscopy and microcomputed tomography. The presence of nanoparticles reduced equilibrium swelling and refined pore architecture, suggesting increased effective cross-linking density and nanoparticle-polymer interactions. Mechanical testing showed soft elastomeric behavior with compressive moduli compatible with cardiac tissue. Under dynamic magnetic stimulation, magnetoelectric hydrogels significantly enhanced cardiac cell viability, proliferation, and morphological organization compared with pristine GelMA controls. After 10 days, the metabolic activity of cells cultured on GelMA-ME NP hydrogels under stimulation was approximately 3-fold higher than that of unstimulated GelMA. These results demonstrate that magnetoelectric hydrogels provide an effective platform for wireless electrostimulation, offering promising opportunities for cardiac tissue engineering and implantable bioelectronic therapies without wired electrodes.
JTD Keywords: Cardiac tissue engineering, Core-shell nanoparticles, Fields, Gelma hydrogels, Magnetoelectric nanocomposites, Tissue, Wireless electrostimulation
Intrarakasem, N, Kaewkarn, S, Proykhunthod, P, Songjaeng, A, Avirutnun, P, Prommool, T, Puttikhunt, C, Makeudom, A, Morchang, A, Tian, XH, Battaglia, G, Patikarnmonthon, N, Kraivong, R, (2026). Intracellular delivery of anti-dengue envelope monoclonal antibodies via PEG-PLGA nanoparticles suppresses viral replication and attenuates hepatocyte apoptosis JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY 118, 108086
Dengue virus (DENV) infection remains a major global health threat, with no specific antiviral treatment currently approved. Monoclonal antibody (mAb) therapy represents a promising strategy for viral inhibition; however, conventional antibodies are largely restricted to extracellular compartments and lack access to intracellular viral replication sites. In this study, we encapsulated a cross-reactive mAb targeting the DENV envelope protein (m513) into poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PEG-PLGA) nanoparticles to facilitate intracellular delivery. When applied to immortalized hepatocyte-like cells (imHCs), the formulation demonstrated efficient cellular uptake, low cytotoxicity, and significantly reduced intracellular viral RNA and protein levels. The resulting formulation consisted of mAb-loaded PEG-PLGA nanoparticles (similar to 100 nm in diameter) with spherical morphology and an encapsulation efficiency of approximately 50%. Furthermore, nanoparticle treatment significantly reduced hepatocyte apoptosis in infected cells. Collectively, these findings demonstrate that nanoparticle-mediated intracellular antibody delivery can overcome a key limitation of conventional antibody therapy and represents a mechanistically distinct antiviral strategy for DENV and other intracellular viral infections.
JTD Keywords: Antibody delivery, Dengue virus, Drug-delivery, Endocytosis, In-vitro, Monoclonal antibody, Peg-plga nanoparticle, Protein
Sharma, P, López, EFP, Nieto, BC, Calò, A, Ghosh, S, Rodríguez, P, Companyó, X, Limburg, B, Kumar, M, (2026). Selective binding of sulphated glycosaminoglycans induces self-assembly of naphthalene diimide into fluorescent nanofibers Nanoscale 18, 6399-6408
The self-assembly of pi-conjugated chromophores directed by biomolecular recognition offers a smart strategy to create bio-synthetic hybrid nanomaterials with emergent properties. Here, we report a novel amphiphilic, cationic naphthalene diimide (NDI) derivative that undergoes supramolecular polymerization upon interaction with anionic glycosaminoglycans (GAGs). Binding of GAGs like heparin to NDIs leads to their supramolecular polymerization in aqueous media. Interestingly, such binding events result in highly emissive fluorescent nanofibers due to the formation of a static excimer. Spectroscopic and microscopic investigations reveal that polyanionic heparin helps to bring the cationic NDIs into close proximity to promote pi-pi stacking and that amphiphilic self-assembly is essential for excimer formation. The heparin binding-induced excimer formation exhibits a clear emission color change from blue to bright green. Furthermore, the NDI selectively binds to sulphated GAGs such as heparin and chondroitin sulphate, but not to carboxylated hyaluronic acid, resulting in a differential fluorescence response. Thus, this study presents a heparin binding-induced supramolecular polymerization of a novel NDI derivative, providing a design strategy for controlling supramolecular order and for creating functional fluorescent nanomaterials for future biosensing and bioimaging applications.
JTD Keywords: Aggregation-induced emission, Chiral induction
dos Santos, FP, Costa, JD, Maier, M, Ballester, BR, Perez, ME, Buxó, X, Gil, MS, Thonon, V, Mura, A, Rodriguez, S, Verschure, P, (2026). Preventing slowing down of alpha rhythms in stroke patients through modulation of cortical excitatory-inhibitory balance: a randomized controlled trial Journal of NeuroEngineering and Rehabilitation 23, 102
Several procedures have been developed to enhance the rehabilitation of stroke patients. However, most techniques struggle to promote sustained recovery in the months following the treatment. Therefore, it is essential to understand the mechanisms that can be harnessed during treatment to potentiate retention of benefits and sustained recovery. While stroke patients often suffer from thalamocortical dysrhythmia (TCD), a perturbation in alpha (8-13 Hz) rhythms caused by decreased excitation in the cortico-thalamic projections, the functional relevance of TCD in stroke patients is not yet clear. We propose that TCD can be counteracted by combining focal stimulation of the motor cortex with virtual-reality (VR) based rehabilitation, which engages distributed networks associated with goal-oriented behavior. Critically, we investigate whether this can be the key to promoting sustained recovery in stroke patients. We compare thalamocortical rhythms and behavioral recovery in patients receiving Sham and bilateral tDCS stimulation of the motor cortex during therapy with the Rehabilitation Gaming System (RGS). Our results reveal that patients in the tDCS group show a sustained recovery in all clinical scales up to three months post-treatment, as opposed to the Sham group. Furthermore, we demonstrate that the slowing down of alpha rhythms can be counteracted by transcranial direct-current stimulation (tDCS), with a particular role for enhancing the excitability of parietal areas. That said, we found no correlation between changes in alpha rhythms and motor recovery. On one hand, our findings suggest that sustained recovery can be potentiated by tDCS-enhanced VR-based rehabilitation. On the other hand, enhancing the excitability of parietal areas while recruiting brain networks associated with goal-oriented behavior can successfully counteract TCD, even though this is likely not the main driver of sustained motor recovery.
JTD Keywords: Activation, Alpha rhythms, Deep brain-stimulation, Direct-current stimulation, Excitatory-inhibitory balance, Guidelines, Human thalamus, Involvement, Motor recovery, Quality-of-life, Rehabilitation, Sensitivity, Stroke, Transcranial direct-current stimulation
Garcia-de-Albeniz, N, Müller, DW, Mücklich, F, Ginebra, MP, Jiménez-Piqué, E, Mas-Moruno, C, (2026). Multiscale hierarchical surface structuring of zirconia using femtosecond laser and chemical etching: implications for cell response and antibacterial performance MATERIALS TODAY BIO 36, 102648
This study investigates a novel strategy combining ultrashort pulsed-direct laser interference patterning (USPDLIP) and chemical etching to create hierarchically micro- and nanorough topographies on zirconia with improved cell-instructive and antibacterial properties. Linear (L3) and grid (G3) micropatterns of 3 mu m periodicity were fabricated via USP-DLIP, and subsequently treated with hydrofluoric acid to introduce an additional homogeneous nanotopography across the patterns. The individual and combined effects of micropatterning and etching on biological responses were evaluated using human mesenchymal stem cells (hMSCs) and two bacterial strains (Pseudomonas aeruginosa and Staphylococcus aureus) in mono- and co-culture settings. Micropatterns primarily guided cell morphology, alignment, and migration, while the introduced nanotopography enhanced focal adhesion formation and modulated cell-surface interactions. Antibacterial effects were found to be topography- and species-specific: micropatterns restricted P. aeruginosa colonization through a bacterial confinement mechanism, whereas etching-induced nanotopography effectively reduced S. aureus adhesion by limiting contact points. In co-culture assays, hMSC survival depended on a complex interplay between cell spreading and bacterial retention, dictated by surface features. Notably, chemical etching improved the antibacterial potential of the patterns against S. aureus, but it did not result in a synergistic improvement on cellular responses. Indeed, among all tested surfaces, the non-etched linear pattern (L3) consistently exhibited the most favorable outcomes -enhancing hMSC adhesion, migration, and osteogenic differentiation and mineralization, while reducing bacterial colonization and supporting cell survival under infection-like co-culture conditions.
JTD Keywords: Antibacterial, Bacterial adhesion, Biofilm formation, Chemical etching, Dental implants, Differentiation, Energy, Growth, Laser patterning, Migration, Nanotopography, Osseointegration, Osteointegration, Titanium, Topography, Zirconia
Razavi, Seyed Ali, Fargas, Gemma, Serrano, Isabel, Laguna-Bercero, Miguel Angel, Vilella, Tania, Llanes, Luis, Rodriguez, Daniel, Ginebra, Maria-Pau, Llorca, Jordi, Morales, Miguel, (2025). Direct recycling of 3D-printed Co-YDZ catalysts for ethanol steam reforming Journal of Environmental Chemical Engineering 13, 120246
Additive manufacturing enhances the catalyst performance via hierarchical design. To address environmental and resource concerns, this work aims to fabricate directly recycled 3D-printed monoliths using Direct-Ink Writing (DIW) from 100 % recovered cobalt-zirconia powders. Virgin cobalt-zirconia monoliths were firstly fabricated by DIW of 3.0-7.0 wt% Co-enriched hydrogel-based ceramic inks, followed by calcination at 600 degrees C in a single thermal treatment. After testing the catalytic performance of monoliths in ethanol steam reforming, 3Dprinted cobalt-zirconia monoliths were fragmented and subjected to subsequent milling and sieving steps to recover composite cobalt-zirconia powders with the appropriate properties for reuse in DIW. The recovered powders, inks and monoliths were microstructurally, rheologically and catalytically characterized, and then compared to catalysts constituted by virgin materials. The rheology properties of inks for the recycled and virgin monoliths presented an appropriate printability. Furthermore, the catalytic performance of recycled monoliths was close to that exhibited by virgin catalysts. This study demonstrates the feasibility of directly recycling fully 3D-printed catalysts, potentially reducing the environmental impact with a circular production model to enhance sustainability in the catalyst industry.
JTD Keywords: Additive manufacturing, Catalyst ethanol steam reforming, Cobalt catalysts, Direct-ink writing, Efficient, Heterogeneous catalyst, Hydrogen production, Ionically conductive supports, Monoliths, Nanoparticles, Oxidation, Performance, Recycled ceramics, Regeneration, Solid oxide fuel, Zirconia
Mulet, Maria, Milan, Jose Antonio Sanchez, Lorca, Cristina, Fernandez-Rhodes, Maria, Adrados-Planell, Ana, Castillo, Maria Consuelo Bejarano, Saiz, Laura, Mateos-Moreno, Maria-Victoria, Hase, Yoshiki, Mira, Alex, Rabano, Alberto, del Ser, Teodoro, Kalaria, Raj N, Lagunas, Anna, Mir, Monica, Crespo, Andres, Samitier, Josep, Gallart-Palau, Xavier, Serra, Aida, (2025). Oral Microbiome-Derived Proteins in Brain Extracellular Vesicles Circulate and Tie to Specific Dysbiotic and Neuropathological Profiles in Age-Related Dementias MOLECULAR & CELLULAR PROTEOMICS 24, 101464
The involvement of the oral microbiome (OM) in the pathophysiology of Alzheimer's disease and vascular dementia has been recognized epidemiologically, but the molecular mechanisms remain elusive. In this study, we uncovered the presence of OM-derived proteins (OMdPs) in brain extracellular vesicles (bEVs) from post-mortem Alzheimer's disease and vascular dementia subjects using unbiased metaproteomics. OMdP circulation in blood EVs was also confirmed in an independent cohort. Our findings also reveal that specific OMdPs are present in bEVs, with their levels varying with disease progression. Peptidome-wide correlation analyses further explored their exchange dynamics and composition within bEVs. In addition, we validated the ability of OM-derived EVs to cross the blood-brain barrier using a blood-brain barrier-on-a-chip model, confirming a potential route for bacterial-derived molecules to reach the central nervous system. Bioinformatics-driven interaction analyses indicated that OMdPs engage with key neuropathological proteins, including amyloid-beta and tau, suggesting a novel mechanism linking dysbiotic OM to dementia. These results provide new insights into the role of the OM in neurodegeneration and highlight OMdPs as potential biomarkers and therapeutic targets.
JTD Keywords: Alzheimers-disease, Communication, Expression, Gut microbiota, Health, Insights, Rna, Virulence factors
Sans, J, Colombi, S, Arnau, M, Fontana-Escartín, A, Resina, L, Garcia-Torres, J, Alemán, C, (2025). Plasma-Assisted and Solvent-Free Ultra-Fast Synthesis of Gold and Gold Oxide Ultra-Small Nanoparticles and its use as Multi-Sensing Platforms Small 21, e06752
In this work, a plasma-assisted and solvent-free synthesis of gold (Au) and gold oxide (Au2O3) nanoparticles (NPs) is explored. Accordingly, only the precursor (i.e., HAuCl4 powder) is exposed to the N-2:O-2 plasma gas mixtures, selected to promote its reduction to Au (HAuCl4-to-Au-0) and/or favor its further oxidation to Au2O3. As a result, the production of highly crystalline spherical Au ultra-small NPs (USNPs) of 2.7 +/- 0.7 nm and Au2O3 edged pyramidal-like NPs of 18 +/- 5 nm is obtained in very short times (i.e., 10 s(-1) min), showing excellent stability without the need to add any ligands. To investigate the potential features of the synthesized particles, they are loaded into alginate hydrogels and tested as multi-detection sensor platforms of H2O2 and NADH in front of several interferents. Although both samples present excellent electrochemical sensing activity (as compared to Au NPs synthesized through the Turkevich method), Au2O3 NPs stand out for its high analytical sensibility toward H2O2 (153.1 and 16.8 mu A mm(-1) cm(-2) for single and multiplexing detection, simultaneously); and capacity to measure NADH in real human urine and low detection limits produced by Escherichia coli (7.5 x 10(3) CFU mL(-1)). Herein, a green, easy, and fast method is proposed to produce stable Au USNPs and Au2O3 NPs, showing great potential for the catalytic and biomedical fields.
JTD Keywords: Au usnps, Au2o3 nps, Multiplexing detection, Nadh, Plasma technologies, Sensing biological environments, Xps
Fischer, Nicholas G, De Jong, David A, Evans, Michael D, Aparicio, Conrado, (2025). Polarity of hemidesmosome instructive light-curable biosealants guides nascent extracellular matrix for favorable epithelial interactions MATERIALS TODAY BIO 35, 102513
Percutaneous medical devices - such as prosthetic limbs, dental implants, and subgingival dental restorations commonly fail due to their susceptibility to infection, posing serious morbidity and mortality and a significant economic burden. Current solutions for subgingival dental restoration failure - such as antimicrobial and degradation-resistant materials - remain largely experimental and have yet to achieve widespread clinical translation. Thus, as a next-generation strategy for improving subgingival restoration longevity, we draw inspiration from the tooth, a long-lasting percutaneous organ with robust soft tissue attachment enabled by cellmatrix adhesive hemidesmosomes (HDs). Promoting HD formation around subgingival restorations - mimicking the natural attachment seen in teeth - may extend dental restoration lifespan by fostering a stable mucosal barrier that blocks bacterial access. A family of scalable biologics-free HD instructive light-curable biosealants (HILBs) was engineered for point-of-care coating for subgingival restorations to trigger and guide beneficial pericellular extracellular matrix structural changes at the HILB surface. Material-based strategies for medical device integration with the human body have traditionally focused on controlling surface properties to provoke desired cellular and tissue responses at the bio/non-bio interface. However, this approach overlooks the evolving pericellular matrix that quickly enrobes cells and overrides engineered surface cues. The control of cell-secreted nascent matrix through HILB surface polarity markedly upregulated HD formation. This bioinstruction is dependent on nascent glycoprotein laminin332 secretion and recognized by HD integrins, which demonstrates the potential of biomaterial surface design to guide secreted pericellular matrix with implications for facilitating tissue repair and enhancing subgingival restoration outcomes.
JTD Keywords: Binding, Bioinspiration, Bioinstructive polar surface, Cells, Expression, Hemidesmosomes, Human keratinocytes, Ionomer, Keratinocytes adhesion, Laminin-5 gamma-2 chain, Light-curable biomaterial, Metalloproteinases, Proteins, Self-etch adhesives, Surface-energy
Esporrín-Ubieto, D, Fraire, JC, Sánchez-deAlcázar, D, Sánchez, S, (2025). Engineered Plasmonic and Fluorescent Nanomaterials for Biosensing, Motion, Imaging, and Therapeutic Applications ADVANCED MATERIALS 37, e2502171-e2502171
The field of nanophotonics has seen remarkable advances, with gold-based materials standing out. By precisely fine-tuning the size and shape of metal nanoparticles (NPs), such as gold nanoparticles (AuNPs), it has been possible to gain control over light interaction, modulating localized surface plasmon resonance (LSPR), a phenomenon that involves the collective oscillation of free conduction electrons. This has opened the path toward more powerful biomedical applications, including surface-enhanced Raman spectroscopy (SERS) and photothermal therapy (PTT). When AuNPs dimensions fall below 2 nm, they become gold nanoclusters (AuNCs), losing the LSPR but acquitting fluorescence due to their molecule-like behavior. This unique feature makes them ideal for high-resolution imaging, biomarker detection, and advanced therapies. Beyond traditional uses, the recent inclusion of AuNPs into nanomotors (NMs) enhances precise in vivo tracking and targeted drug delivery. This review highlights the different applications of plasmonic nanomaterials with particular emphasis on AuNPs and AuNCs as a function of their shapes, sizes, and stabilization ligands. Moreover, it dives into the biosensing applications of plasmonic materials by addressing their so-called far-field and near-field optical properties, giving a detailed overview of different high-sensitivity immunoassays and biosensing. A comprehensive outlook on the evolution of plasmonic-based materials for the next therapies is provided.
JTD Keywords: Albumin-gold nanoclusters, Cancer-cells, Gold nanoparticles, Intracellular ph, Microwave-assisted synthesis, Nanoclusters, Nanomotors, Optical-properties, Plasmonic biosensors, Protein-directed synthesis, Rapid synthesi, Resonance immunoassay, Ser, Sers, Silver nanoparticles, Ultrasensitive detection
Parrilla-Gomez, Francisco Jose, Castellvi-Font, Andrea, Boutonnet, Victor, Parrilla-Gomez, Andres, Terreros, Marta Antolin, Somoza, Cristina Mestre, Bravo, Marina Blanes, de la Rubia, Paola Pratsobrerroca, Martin-Lopez, Eva, Marco, Santiago, Festa, Olimpia, Brochard, Laurent J, Goligher, Ewan C, Enviz, Joan Ramon Masclans, (2025). Association of Breathing Effort With Survival in Patients With Acute Respiratory Distress Syndrome CRITICAL CARE MEDICINE 53, e1982-e1994
OBJECTIVES: Invasive mechanical ventilation (IMV) is crucial for acute respiratory distress syndrome (ARDS) management, but mortality remains high. While spontaneous breathing is key to weaning, excessive respiratory effort may injure the lung and diaphragm. Most existing data on respiratory effort during IMV are based on brief periods of observation, potentially underestimating the burden of inappropriate efforts. This study aims to characterize the evolution of respiratory effort over time in ARDS patients and its relation to survival. We hypothesized that nonsurvivors would spend a greater proportion of time in the high-effort range during the active breathing phase compared with survivors. DESIGN, SETTING, AND PATIENTS: In this prospective cohort study, we continuously recorded airway pressure, flow, esophageal, and gastric pressures in ARDS patients on mechanical ventilation during 7 days after the onset of spontaneous breathing. We analyzed physiologic respiratory effort variables, focusing on the proportion of time spent within defined effort ranges, and compared these data between ICU survivors and nonsurvivors. Statistical analysis was conducted using variance weighted methods to account for variability in the number of respiratory cycles analyzed per patient. This study is registered at ClinicalTrials.gov under identifier NCT06490523. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 1,485,405 respiratory cycles were analyzed from 26 ARDS patients (19 survivors, seven nonsurvivors). Nonsurvivors spent significantly more time in high effort (12% vs. 3%; p = 0.006). In contrast, survivors spent more time in the moderate-effort range (50% vs. 5%; p < 0.001). The time spend with high dynamic transpulmonary driving pressure (> 25 cm H2O) was also significantly different between groups (32% survivors vs. 74% nonsurvivors; p = 0.001). CONCLUSIONS: Patients who die of ARDS are more likely to be exposed to high respiratory effort for prolonged periods of time compared with survivors.
JTD Keywords: Acute respiratory distress syndrome, Adult patients, Epidemiology, Esophageal, Esophageal pressure, Evolution, Lung injury, Mechanical ventilation, Mortality, Pressure support ventilation, Pulmonary, Respiratory effort, Transpulmonary pressure
Arboleda, Alejandro, Franco, Manuel, Naranjo, Francisco, Giraldo, Beatriz Fabiola, (2025). Electromyographic Diaphragm and Electrocardiographic Signal Analysis for Weaning Outcome Classification in Mechanically Ventilated Patients SENSORS 25, 6000
Early prediction of weaning outcomes in mechanically ventilated patients has significant potential to influence the duration of treatment as well as associated morbidity and mortality. This study aimed to investigate the utility of signal analysis using electromyographic diaphragm (EMG) and electrocardiography (ECG) signals to classify the success or failure of weaning in mechanically ventilated patients. Electromyographic signals of 40 subjects were recorded using 5-channel surface electrodes placed around the diaphragm muscle, along with an ECG recording through a 3-lead Holter system during extubation. EMG and ECG signals were recorded from mechanically ventilated patients undergoing weaning trials. Linear and nonlinear signal analysis techniques were used to assess the interaction between diaphragm muscle activity and cardiac activity. Supervised machine learning algorithms were then used to classify the weaning outcomes. The study revealed clear differences in diaphragmatic and cardiac patterns between patients who succeeded and failed in the weaning trials. Successful weaning was characterised by a higher ECG-derived respiration amplitude, whereas failed weaning was characterised by an elevated EMG amplitude. Furthermore, successful weaning exhibited greater oscillations in diaphragmatic muscle activity. Spectral analysis and parameter extraction identified 320 parameters, of which 43 were significant predictors of weaning outcomes. Using seven of these parameters, the Naive Bayes classifier demonstrated high accuracy in classifying weaning outcomes. Surface electromyographic and electrocardiographic signal analyses can predict weaning outcomes in mechanically ventilated patients. This approach could facilitate the early identification of patients at risk of weaning failure, allowing for improved clinical management.
JTD Keywords: Cardiorespiratory characterisation, Classification, Coherence, Diaphragm, Ecg, Electromyography, Emg, Heart-rate-variability, Mechanical ventilation, Naive bayes classifier, Predictor, Signal analysis, Surface electromyography, Time-series analysis, Time-varying spectral analysis, Weaning outcome
Lin, Jinwei, Guan, Qiaoxin, Feng, Jiangqi, Chen, Shuqin, Xu, Leilei, Guan, Jianguo, Sanchez, Samuel, (2025). Interactions Between Active Matters and Endogenous Fields ADVANCED MATERIALS 37, e03091
Active matter, encompassing both natural and artificial systems, utilizes environmental energy to sustain autonomous motion, exhibiting unique non-equilibrium behaviors. Artificial active matter (AAM), such as nano/micromotors, holds transformative potential in precision medicine by enhancing drug delivery and enabling targeted therapeutic interventions. Under the demand for increasing intelligence in AAM, controlling their non-equilibrium processes within complex in vivo environments presents significant challenges. Endogenous fields-biological fields generated within living systems-play a pivotal role in guiding natural active matter's (NAM) directional migration and collective transformations, offering a strategy for in vivo control of non-equilibrium systems. Research in NAMs-inspired AAMs spans biology, chemistry, materials science, engineering, and physics, yet communication barriers among disciplines often impede progress. This review seeks to bridge these gaps by summarizing the key characteristics of chemical and physical endogenous fields in biological contexts such as tumors, wounds, and inflammation. It explores how natural and artificial active matter sense, transmit, and execute responses to these fields, and discusses how insights from natural systems can inform the design of synthetic counterparts. Potential issues and prospects of this research direction are also discussed. It is hoped that this review fosters interdisciplinary collaborations and propels the development of intelligent active matter for biomedical applications.
JTD Keywords: Acoustic propulsion, Active matter, Cell-migration, Collective behavior, Endogenous fields, Exhaled breath condensate, Extracellular ph, Hydrogen-peroxide, In-vivo, Interstitial fluid pressure, Nanomotors, Shear-wave elastography, Stimuli-responsive polymers, Tumor microenvironment
Bernardo, Alejandro, Diaz-Valdivia, Natalia, Fernandez-Nogueira, Patricia, Alcaraz, Jordi, (2025). Stromagenesis and cancer-associated fibroblast heterogeneity in primary tumors and metastasis: focus in non-small cell lung cancer FEBS Open Bio 15, 1599-1617
Non-small cell lung cancer (NSCLC) is the most common lung cancer type and one of the deadliest neoplasias worldwide. NSCLC is histologically classified into adenocarcinoma, squamous cell carcinoma, and other less frequent subtypes. Both subtypes and other solid tumors are increasingly regarded as abnormal organs, highlighting the critical role of the desmoplastic tumor stroma rich in cancer-associated fibroblasts (CAFs) in driving tumor progression and therapeutic resistance. This tumor stroma resembles a chronic fibrotic wound and is largely formed by activated/myofibroblast-like alpha-SMA+ CAFs (myCAFs), which are strongly associated with immunosuppression and poor prognosis. Despite the dominance of the myCAF phenotype, we reported a decade ago phenotypic alterations in NSCLC with a strong dependence on the histologic subtype. Subsequent studies using functional assays, single-cell techniques, and in vivo models have refined these initial observations, enhancing our understanding of the biology of both normal fibroblasts/myofibroblasts and CAFs in NSCLC and other cancer types, including their origins, subclassification, and physiopathologic functions. Notably, increasing evidence supports that CAFs can exhibit tumor-restraining or tumor-promoting effects, and current therapeutic efforts aim to shift the balance towards tumor-restraining phenotypes. Here, we review major advances in our understanding of tumor stromagenesis and CAF heterogeneity in both primary tumors and metastasis, including emerging consensus, with a special focus on NSCLC and its frequent dissemination to the brain. We also highlight the critical role of smoking through epigenetic reprogramming of the TGF-beta/SMAD3 pathway. These advances are beginning to delineate how CAF heterogeneity depends on the stage and histologic subtype in NSCLC.
JTD Keywords: Accumulation, Activation, Cancer-associated fibroblasts, Carcinoma-associated-fibroblasts, Desmoplasia, Differentiation, Generation, Localization, Metastasis, Microenvironment, Myofibroblast, Myofibroblasts, Non-small cell lung cancer, Progression, Stroma, Stromagenesis
Maleeva, Galyna, Matera, Carlo, Roda, Silvia, Colleoni, Alessio, De Amici, Marco, Gorostiza, Pau, (2025). Molecular Tools to Study and Control Dopaminergic Neurotransmission With Light MEDICINAL RESEARCH REVIEWS 45, 1407-1422
Dopaminergic neurotransmission is involved in several important brain functions, such as motor control, learning, reward-motivated behavior, and emotions. Dysfunctions of dopaminergic system may lead to the development of various neurological and psychiatric disorders, like Parkinson's disease, schizophrenia, depression, and addictions. Despite years of sustained research, it is not fully established how dopaminergic neurotransmission governs these important functions through a relatively small number of neurons that release dopamine. Light-driven neurotechnologies, based on the use of small light-regulated molecules or overexpression of light-regulated proteins in neurons, have greatly contributed to the advancement of our understanding of dopaminergic circuits and our ability to control them selectively. Here, we overview the current state-of-the-art of light-driven control of dopaminergic neurotransmission. While we provide a concise guideline for the readers interested in pharmacological, pharmacogenetic, and optogenetic approaches to modulate dopaminergic neurotransmission, our primary focus is on the usage of photocaged and photo-switchable small dopaminergic molecules. We argue that photopharmacology, photoswitchable molecules of varied modalities, can be employed in a wide range of experimental paradigms, providing unprecedent insights into the principles of dopaminergic control, and represent the most promising light-based therapeutic approach for spatiotemporally precise correction of dopamine-related neural functions and pathologies.
JTD Keywords: Activation, Azobenzene, Caged compounds, Caged ligands, Catecholamine, D1, D2, Dendritic spines, Dopamine, Mechanisms, Neuromodulation, Neuronal circuits, Optogenetics, Optopharmacology, Phasic dopamine, Photoisomerization, Photolysi, Photopharmacology, Photoswitc, Protein-coupled receptors, Release
Arboleda A, Franco M, Valladares L, Naranjo F, Giraldo BF, (2025). Entropy analysis of diaphragmatic EMG signals as an indicator of extubation viability in mechanically ventilated patients. Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference 2025, 1-4
Surface electromyographic (sEMG) signals from the diaphragm has become a valuable tool for monitoring muscle activity during the weaning process from mechanical ventilation. However, EMG signals are inherently nonlinear and susceptible to noise contamination, which poses challenges for traditional signal processing methods. In this study, we propose the use of entropy metrics to evaluate the dynamic complexity and irregularity of surface electromyographic (EMG) signals of patients assisted with mechanical ventilation. Shannon entropy and spectral entropy were computed to analyze EMG signals from two surface diaphragm channels recorded in mechanically ventilated patients during extubation preparation. According to clinical criteria, the patients were classified into the successful group (GE) - 19 patients with successful extubation after 48 hours, and the failure group (GF) - 21 patients who required reconnection to the ventilator within 48 hours. sEMG signals were recorded using 5-channel surface electrodes placed around the diaphragm muscle. Shannon and spectral entropies were calculated using a 0.5-minute window with an overlap of 80%. The results presented a greater complexity of the EMG signal in the SG group. This group shows higher peaks in Shannon entropy and elevated spectral entropy values compared to the FG group. Channels 2 and 3 presented the largest statistically significant differences.Clinical Relevance- Analyzing diaphragm EMG signals using entropy metrics could improve patient outcomes by optimizing the timing of extubation. These metrics would serve as a key indicator of readiness for extubation, providing an objective basis for more informed clinical decision-making.
JTD Keywords: Aged, Airway extubation, Diaphragm, Electromyography, Entropy, Female, Humans, Male, Middle aged, Respiration, artificial, Signal processing, computer-assisted, Ventilator weaning
Garcia-de-Albeniz, N, Ginebra, MP, Jiménez-Piqué, E, Mas-Moruno, C, (2025). Chemical etching-induced nanoroughness enhances cell response and antibacterial activity on zirconia JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 45, 117236
Surface topography at the nanoscale plays a crucial role in modulating the biological properties of dental implants. However, the understanding of how the nanoroughness of zirconia affects cell and bacteria responses remains unclear. In this study, chemical etching of 3Y-TZP was explored to develop a nanotopography capable of favoring eukaryotic cell behavior while simultaneously inhibiting bacterial adhesion. Three topographies of different roughness were created by varying the etching time with hydrofluoric acid (i.e., HF15, HF30, and HF60). The etched surfaces exhibited a nanorough topography with randomly distributed nanopits, and surface roughness increased at longer etching times. Mesenchymal stem cell adhesion, spreading, proliferation and mineralization were enhanced on the etched surfaces, compared to flat controls. The roughest surface (HF60) also inhibited S. aureus adhesion and caused significant damage to P. aeruginosa. This study highlights the potential of chemical etching to produce nanorough zirconia with improved biological outcomes.
JTD Keywords: Attachment, Bacteri, Bacterial adhesion, Biomaterials, Cell response, Chemical etching, Dental implants, Dental zirconia, Integration, Osseointegration, Osteogenic differentiation, Parameter, Roughness, Surface-topography, Titanium implants, Zirconia
Lopez-Gomez, P, Mehwish, N, Marchan, V, Ginebra, M P, Mas-Moruno, C, (2025). Tailoring Self-Assembled Peptide Hydrogels with Antimicrobial or Cell Adhesive Properties for Tissue Engineering CHEMISTRY-A EUROPEAN JOURNAL 31, e202500975
Bacterial colonization on biomaterials is a major issue, leading to approximately 20% of implant failures due to infection and biofilm formation. To address this, peptide-based hydrogels incorporating tailored bioactive peptides have emerged as promising candidates for applications in tissue engineering and infection control. Here, we have designed peptide sequences that incorporate i) a self-assembling unit (SaU) and ii) bioactive motifs, including the well-known arginine-glycine-aspartate (RGD) sequence to promote cell adhesion or an antimicrobial peptide derived from lactoferrin (LF) to exhibit antibacterial properties. To aid in the gelation, these peptides were combined with hyaluronic acid (HA), rendering peptide-based hydrogels without the need for additional external assembly triggers, simplifying their application in biomedical contexts. This protocol allowed for a spontaneous formation of a 3D fibrillar network, with structural and physicochemical properties suitable for tissue engineering. The biological evaluation revealed the ability of RGD-based hydrogels to increase the adhesion and spreading of osteoblastic cells compared to controls, while the LF-based hydrogels significantly reduced the viability and attachment of both Gram-positive and Gram-negative strains, clearly affecting bacterial morphology. This report demonstrates the feasibility of this technology to produce hydrogels incorporating distinct biological cues, highlighting their potential as versatile biomaterials to address diverse biomedical challenges.
JTD Keywords: Alginate, Antimicrobial peptide, Bacterial adhesion, Biomaterial, Cell adhesion, Circular-dichroism, Design, Hlf1-11 peptide, Human lactoferrin, Hyaluronic-acid, Lf, Molecules, Peptide-based hydrogels, Rgd, Self-assembling peptide, Titanium
Colombi, S, Alemán, C, García-Torres, J, (2025). Free-standing, flexible and conformable bilayered polymeric nanomembranes modified with gold nanomaterials as electronic skin sensors COLLOIDS AND SURFACES B-BIOINTERFACES 250, 114558
Skin is a barrier that protects us against physical, chemical and biological agents. However, any damage to the skin can disrupt this barrier and therefore compromise its function leading to sometimes catastrophic consequences like sepsis. Thus, methods to detect early signs of infection are necessary. In this work, we have developed a straightforward method for producing 2D nanomembranes with regularly spaced 1D metallic nanostructures integrating sensing capabilities to pH and NADH (nicotinamide adenine dinucleotide), which are critical analytes revealing infection. To achieve this, we have successfully fabricated a bilayered nanomembrane combining a pH-responsive polyaniline (PANI) layer and a nanoperforated poly(lactic acid) (PLA) layer containing gold nanowires (Au NWs) as NADH sensing element. SEM, FTIR, Raman and AFM techniques revealed the formation of the bilayered PANI/PLA nanomembrane and the successful incorporation of the Au NWs inside the nanoperforations. The resulting bilayered nanomembrane showed significant flexibility and conformability onto different substrates due to the softness of the polymers and the ultrathin thickness with stiffness values similar to human skin. These nanomembranes also exhibited remarkable electrochemical sensing performance towards pH and NADH detection. Thus, the nanomembrane displayed linearity with good sensitivity (47 mVpH-1) in the critical pH range 4-10 and fast response time (10 s). On the other hand, PANI/PLA-Au nanomembranes also allowed the quantitative sensing of NADH with a limit of detection of 0.39 mM and a sensitivity of 1 mu A cm-2 mM-1 in the concentration range 0-5 mM.
JTD Keywords: Bilayered nanomembranes, Biomimetic membranes, Free-standing films, Gold nanowires, Nad, Nanoparticles, Pani, Ph and nadh sensor, Pla, Polyaniline
Arnau, Marc, Sans, Jordi, Turon, Pau, Aleman, Carlos, (2025). Sustainable oxidation of methane into formic acid using a polarized bioceramic under mild reaction conditions Sustainable Energy & Fuels 14, 3808-3819
The conversion of methane into useful chemicals has an enormous interest from both economic and social points of view as it is an important feedstock in chemical industry and is the second most important greenhouse gas contributor to climate change. In this work, we report the sustainable and selective conversion of methane into formic acid in batch and continuous-flow conditions using a biocatalyst made of permanently polarized. Formic acid was the only product identified in absence of UV irradiation, while a mixture of formic acid and methanol was obtained under UV light. The reaction pathway was investigated, on the one hand experimentally, by varying the reaction time, temperature and pressure in a batch reactor, in addition to the analysis of gaseous products, which allowed to understand the role of UV light in the change of selectivity, and on the other hand theoretically, using Density Functional Theory (DFT) computer calculations. The reaction pathway was experimentally investigated varying the reaction time, temperature and pressure in a batch reactor, besides gas products analysis, enabling to understand the UV light role in selectivity shift. Continuous-flow reactions using non-irradiated catalysts were conducted at 120 degrees C, produced a formic acid yield of 4.2 mmol per gram of catalyst and hour.
JTD Keywords: Amino-acid, Direct conversion
Razavi, SA, Fargas, G, Vilella, T, Serrano, I, Laguna-Bercero, MA, Llanes, L, Rodríguez, D, Ginebra, MP, Llorca, J, Morales, M, (2025). Direct Ink Writing of cobalt-zirconia monoliths for catalytic applications: A novel single-step fabrication approach JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 45, 117137
Additive manufacturing technologies are revolutionizing the fabrication of ceramic catalysts through hierarchical design to enhance catalytic performance and simultaneously improving the efficiency of the manufacturing process by decreasing the initial investment and production steps. This work proposes a fabrication process of cobalt-zirconia monoliths based on Direct-Ink Writing of Co-enriched hydrogel-based ceramic inks, and the debinding and sintering at 600 degrees C in a single thermal treatment. The effect of Co precursor amount (3.0 -7.0 wt% Co) on the rheological properties of inks and the catalytic performance in ethanol steam reforming is investigated. The results reveal the successful incorporation of Co into rectilinear monoliths with 50% infill, obtaining strongly Co-rich surfaces. The remarkable catalytic performance of the 5.0 wt% Co monolith at 300-600 degrees C confirms the feasibility of this novel single-step approach, reaching an appropriate balance between catalytic activity and printability. This outcome may represent a push towards the fabrication of fully 3D-printed monolithic catalysts.
JTD Keywords: Additive manufacturing, Catalyst ethanol steam reforming, Cleanup, Co, Combustion, Direct-ink writing, Hydrogen productio, Ionically conductive supports, Nanoparticles, Oxidation, Rama, Reactors, Sulfur, Zirconia
Rogkoti, Theodora, Donnelly, Hannah, Dalby, Matthew J, Salmeron-Sanchez, Manuel, (2025). Mechanical signatures and models of the bone marrow niche Nature reviews bioengineering 3, 697-713
The bone marrow is a complex tissue with distinct cellular and mechanical heterogeneity, serving as the primary site for haematopoiesis. Under certain conditions, such as on the onset of mutations to healthy cells or alterations to the environment, the bone marrow can also become the origin of haematological malignancies, often characterized by uncontrolled self-renewal of hematopoietic stem cells, overproduction of immature progeny and remodelling of the tissue microenvironment. This remodelling alters the composition and mechanics of the extracellular matrix (ECM), facilitating the proliferation and metastasis of leukaemic cells. The elastic and dissipative properties of the ECM are hallmarks of both health and disease progression in different tissues. However, studying the mechanical properties of bone marrow is difficult owing to inaccessibility in situ. Advanced three-dimensional bioengineered models offer a way to recapitulate the mechanical properties of the bone marrow, but it remains challenging to incorporate the elastic and viscous components. Understanding the physiological and disease-specific mechanical ECM signatures is crucial for advancing bone marrow research and for developing therapeutics. In this Review, we explore the structure-function relationship of the bone marrow, emphasizing its complex mechanical behaviour, and discuss the bioengineered models that recapitulate the mechanical properties in the healthy and diseased bone marrow niche, stressing the importance of replicating ECM physiological and pathological mechanical signatures in the future.
JTD Keywords: Acute myeloid-leukemia, Extracellular-matrix stiffness, Fibrosis, Hematopoietic stem-cell, Lysyl-oxidase, Mesenchymal stromal cells, Microenvironment, N-cadherin, Progenitor cells, Suppor
Alcacer-Almansa, Julia, Blanco-Cabra, Nuria, Torrents, Eduard, (2025). Burkholderia cenocepacia and Pseudomonas aeruginosa in dual-species models: Insights into population distribution, antibiotic susceptibility, and virulence Virulence 16, 2494039
Multispecies biofilms are communities composed of different microorganisms embedded in an auto-synthesized polymeric matrix. Pseudomonas aeruginosa and Burkholderia cenocepacia are two multidrug-resistant and biofilm-forming opportunistic pathogens often found in the lungs of people living with cystic fibrosis. In this context, planktonic, static, and dynamic biofilms and in vivo models of both species were optimized in this work to understand their population dynamics, disposition, virulence, and antibiotic susceptibility. From the coculture models optimized in this work, we determined that B. cenocepacia grows in a clustered, aggregative manner at the bottom layers of biofilms, in close contact with P. aeruginosa, that tends to occupy the top layers. Their coexistence increases virulence-related gene expression in both species at early stages of coinfection and in in vivo models, while there was a general downregulation of virulence-related genes after longer coexistence periods as they eventually reach a non-competitive stage during chronic infections. When evaluating antimicrobial susceptibility, a decrease of antimicrobial tolerance was observed in both species when co-cultured. These findings shed light on the differential behavior of P. aeruginosa and B. cenocepacia in dual-species systems, stressing the relevance of multispecies studies in the clinical context.
JTD Keywords: Antibiotic, Biofilm spatial distribution, Biofilms, Cepacia, Coinfection, Cystic-fibrosis, Gene expressio, Infection, Persistence, Polymicrobial biofilm, Virulence
White, T, López-Márquez, A, Badosa, C, Jimenez-Mallebrera, C, Samitier, J, Giannotti, MI, Lagunas, A, (2025). Nanomechanics of cell-derived matrices as a functional read-out in collagen VI-related congenital muscular dystrophies Journal of the Royal Society Interface 22, 20240860
Changes in the mechanical properties of the extracellular matrix (ECM) are a hallmark of disease. Due to its relevance, several in vitro models have been developed for the ECM, including cell-derived matrices (CDMs). CDMs are decellularized natural ECMs assembled by cells that closely mimic the in vivo stromal fibre organization and molecular content. Here, we applied atomic force microscopy-force spectroscopy (AFM-FS) to evaluate the nanomechanical properties of CDMs obtained from patients diagnosed with collagen VI-related congenital muscular dystrophies (COL6-RDs). COL6-RDs are a set of neuromuscular conditions caused by pathogenic variants in any of the three major COL6 genes, which result in deficiency or dysfunction of the COL6 incorporated into the ECM of connective tissues. Current diagnosis includes the genetic confirmation of the disease and categorization of the phenotype based on maximum motor ability, as no direct correlation exists between genotype and phenotype of COL6-RDs. We describe differences in the elastic modulus (E) among CDMs from patients with different clinical phenotypes, as well as the restoration of E in CDMs obtained from genetically edited cells. Results anticipate the potential of the nanomechanical analysis of CDMs as a complementary clinical tool, providing phenotypic information about COL6-RDs and their response to gene therapies.
JTD Keywords: Atomic force microscopy-based force spectroscopy, Bethlem myopathy, Cell-derived matrices, Collagen vi-related congenital muscular dystrophies, Elastic modulus, Extracellular matrix, Extracellular-matrix, Fibroblasts, Gene editin, Microenvironment, Migration, Mode, Muscle, Position, Progenitors, Stiffness
Martinez, Xavier Llorens, Macarrilla, Leonardo Ruiz, Rey-Vinolas, Sergi, Mateos-Timoneda, Miguel A, Engel, Elisabeth, Guix, J M Mora, (2025). Study of bone-tendon interface healing in an animal model using a synthetic scaffold and PRP European Journal of Trauma and Emergency Surgery 51, 124
PurposeBiological matrices have been used to reinforce large rotator cuff tear repairs. However, rapid resorption and initial immune reactions presented challenges in clinical practice. This study evaluates whether a resorbable synthetic matrix (scaffold), used alone or with platelet-rich plasma (PRP), impacts repair processes at microscopic, ultrasound, and biomechanical levels in a rabbit model of induced tendon-bone interface injury.MethodsAn experimental study was performed on 24 rabbits. Two experimental groups (n = 12 each) and a control group (n = 24) were defined. In the first group (BioP), the internal gastrocnemius tendon was sectioned and repaired to bone using double-row sutures, reinforced with a PLC (poly-L-lactic-co-epsilon-caprolactone) and PLA (polylactic acid) scaffold. In the second group (BioP + PRP), autologous PRP was added to the repair. The control group received no scaffold or PRP. Euthanasia was performed at 8 weeks, followed by microscopic, ultrasound, and biomechanical evaluations.ResultsMicroscopically, a granulomatous reaction limited to the foreign body was observed in both scaffold groups. The healing process was not altered in any group, showing good biocompatibility of the scaffold. Echographically, a greater sagittal diameter was observed in the group without PRP compared to the other groups. Biomechanically, no significant differences in rupture zones were found across groups, but the scaffold-only group required a higher maximum applied force before rupture.ConclusionsAt 8 weeks, using a degradable synthetic PLC and PLA scaffold as support at the bone-tendon interface did not significantly alter the normal repair process, showed echographic and biomechanical benefits, and PRP did not show additional benefits in our experimental model.
JTD Keywords: Augmentation, Biology, Biomaterials, Cells, Efficacy, Ge, Matrix, Platelet-rich plasma, Regeneration, Rotator cuff repair, Shoulder, Surgical repair, Technologies, Tissue engineerin
Drainas AP, McIlwain DR, Dallas A, Chu T, Delgado-González A, Baron M, Angulo-Ibáñez M, Trejo A, Bai Y, Hickey JW, Lu G, Lu S, Pineda-Ramirez J, Anglin K, Richardson ET, Prostko JC, Frias E, Servellita V, Brazer N, Chiu CY, Peluso MJ, Martin JN, Wirz OF, Pham TD, Boyd SD, Kelly JD, Sage J, Nolan GP, Rovira-Clavé X, (2025). High-throughput multiplexed serology via the mass-spectrometric analysis of isotopically barcoded beads Nature Biomedical Engineering 9, 1117-1128
In serology, each sample is typically tested individually, one antigen at a time. This is costly and time consuming. Serology techniques should ideally allow recurrent measurements in parallel in small sample volumes and be inexpensive and fast. Here we show that mass cytometry can be used to scale up multiplexed serology testing by leveraging polystyrene beads uniformly loaded with combinations of stable isotopes. We generated 18,480 unique isotopically barcoded beads to simultaneously detect, in a single tube with 924 serum samples, the levels of immunoglobulins G and M against 19 proteins from SARS-CoV-2 (a total of 36,960 tests in 400 nl of sample volume and 30 mu l of reaction volume). As a rapid, high-throughput and cost-effective technique, serology by mass cytometry may contribute to the effective management of public health emergencies originating from infectious diseases.
JTD Keywords: Antibodies, viral, Biolog, Covid-19, Covid-19 serological testing, Cytometer, High-throughput screening assays, Humans, Immunoglobulin g, Immunoglobulin m, Mass spectrometry, Microspheres, Polystyrenes, Sars-cov-2, Transmission
Perucca, Alice, Llonin, Andrea Gomez, Benach, Oriol Mane, Hallopeau, Clement, Rivas, Elisa I, Linares, Jenniffer, Garrido, Marta, Sallent-Aragay, Anna, Golde, Tom, Colombelli, Julien, Dalaka, Eleni, Linacero, Judith, Cazorla, Marina, Galan, Teresa, Pastor Viel, Jordi, Badenas, Xavier, Recort-Bascuas, Alba, Comerma, Laura, Fernandez-Nogueira, Patricia, Rovira, Ana, Roca-Cusachs, Pere, Albanell, Joan, Trepat, Xavier, Calon, Alexandre, Labernadie, Anna, (2025). Micro Immune Response On-chip (MIRO) models the tumour-stroma interface for immunotherapy testing Nature Communications 16, 1279
Immunotherapies are beneficial for a considerable proportion of cancer patients, but ineffective in others. In vitro modelling of the complex interactions between cancer cells and their microenvironment could provide a path to understanding immune therapy sensitivity and resistance. Here we develop MIRO, a fully humanised in vitro platform to model the spatial organisation of the tumour/stroma interface and its interaction with immune cells. We find that stromal barriers are associated with immune exclusion and protect cancer cells from antibody-dependent cellular cytotoxicity, elicited by targeted therapy. We demonstrate that IL2-driven immunomodulation increases immune cell velocity and spreading to overcome stromal immunosuppression and restores anti-cancer response in refractory tumours. Collectively, our study underscores the translational value of MIRO as a powerful tool for exploring how the spatial organisation of the tumour microenvironment shapes the immune landscape and influences the responses to immunomodulating therapies.
JTD Keywords: Activation, Animals, Architecture, Breast-cancer, Cancer-associated fibroblasts, Cell line, tumor, Collagen, Female, Humans, Immunomodulation, Immunotherapy, Interleukin-2, Lab-on-a-chip devices, Mechanism, Mice, Microenvironment, Migration, Neoplasms, Stromal cells, T-cells, Therap, Tumor microenvironment
Arévalo-Jaimes, BV, Admella, J, Torrents, E, (2025). Who arrived first? Priority effects on Candida albicans and Pseudomonas aeruginosa dual biofilms Communications Biology 8, 160
Historical processes in community assembly, such as species arrival order, influence interactions, causing priority effects. Candida albicans and Pseudomonas aeruginosa often co-occur in biofilm-based infections of the skin, lungs, and medical devices. Their predominantly antagonistic relationship involves complex physical and chemical interactions. However, the presence and implications of priority effects among these microorganisms remain largely unexplored. Here, we investigate the presence and impact of priority effect in dual-species biofilms using clinical isolates. By varying inoculation order, we observe significant changes in biofilm composition, structure, virulence, and antimicrobial susceptibility. The first colonizer has an advantage for surface colonization. Consecutive colonization increases biofilm virulence and negates C. albicans' protective effect on P. aeruginosa PAET1 against meropenem treatment. Finally, we propose N-acetylcysteine as an adjuvant for treating C. albicans and P. aeruginosa interkingdom infections, working independently of priority effects.
JTD Keywords: Airway colonization, Bacteria, Infections, Pneumonia, Spp., Virulenc
Zhu, BK, Bai, YH, Yeo, YY, Lu, XW, Rovira-Clavé, X, Chen, H, Yeung, J, Nkosi, D, Glickman, J, Delgado-Gonzalez, A, Gerber, GK, Angelo, M, Shalek, AK, Nolan, GP, Jiang, SZ, (2025). A multi-omics spatial framework for host-microbiome dissection within the intestinal tissue microenvironment Nature Communications 16, 1230
The intricate interactions between the host immune system and its microbiome constituents undergo dynamic shifts in response to perturbations to the intestinal tissue environment. Our ability to study these events on the systems level is significantly limited by in situ approaches capable of generating simultaneous insights from both host and microbial communities. Here, we introduce Microbiome Cartography (MicroCart), a framework for simultaneous in situ probing of host and microbiome across multiple spatial modalities. We demonstrate MicroCart by investigating gut host and microbiome changes in a murine colitis model, using spatial proteomics, transcriptomics, and glycomics. Our findings reveal a global but systematic transformation in tissue immune responses, encompassing tissue-level remodeling in response to host immune and epithelial cell state perturbations, bacterial population shifts, localized inflammatory responses, and metabolic process alterations during colitis. MicroCart enables a deep investigation of the intricate interplay between the host tissue and its microbiome with spatial multi-omics.
JTD Keywords: Animals, Bacteria, Cellular microenvironment, Colitis, Design, Disease models, animal, Environment, Fis, Gastrointestinal microbiome, Glycomics, Host microbial interactions, Intestinal mucosa, Intestines, Male, Mice, Mice, inbred c57bl, Multiomics, Organization, Probes, Proteins, Proteomics, Rna, Subcellular resolution, Transcriptome
Rubí-Sans, G, Nyga, A, Mateos-Timoneda, MA, Engel, E, (2025). Substrate stiffness-dependent activation of Hippo pathway in cancer associated fibroblasts BIOMATERIALS ADVANCES 166, 214061
The tumor microenvironment (TME) comprises a heterogenous cell population within a complex threedimensional (3D) extracellular matrix (ECM). Stromal cells within this TME are altered by signaling cues from cancer cells to support uncontrolled tumor growth and invasion events. Moreover, the ECM also plays a fundamental role in tumor development through pathological remodeling, stiffening and interaction with TME cells. In healthy tissues, Hippo signaling pathway actively contributes to tissue growth, cell proliferation and apoptosis. However, in cancer, the Hippo signaling pathway is highly dysregulated, leading to nuclear translocation of the YAP/TAZ complex, which directly contributes to uncontrolled cell proliferation and tissue growth, and ECM remodeling and stiffening processes. Here, we compare the effect of increasing cell culture substrate stiffness, derived from tumor progression, upon the dysregulation of the Hippo signaling pathway in colorectal cancer-associated fibroblasts (CAFs) and normal colorectal fibroblasts (NFs). We correlate the dysregulation of Hippo pathway with the magnitude of the traction forces exerted by healthy and malignant stromal cells. We found that ECM stiffening is crucial in Hippo pathway dysregulation in CAFs, but not in normal fibroblasts.
JTD Keywords: Cancer-associated fibroblasts, Hippo pathway, Organ size control, Tissu, Tumor microenvironment, Yap-ta, Yap/taz
Acevedo, HG, Arizmendi, CJ, Giraldo, BF, (2025). Analysis of Respiratory Flow Signals Using Poincare Plot Descriptors for Machine Learning-Based Prediction of Ventilator Weaning Success IEEE Access 13, 170523-170534
Acute respiratory distress syndrome (ARDS) is a severe pulmonary condition that often requires mechanical ventilation (MV) to ensure adequate gas exchange and minimize ventilator-induced lung injury. This study compares statistical descriptors derived from respiratory time series with nonlinear variability metrics obtained from Poincar & eacute; plots to predict the outcomes of the weaning process in mechanically ventilated patients. The database, which includes respiratory flow recordings from 243 patients who underwent a standardized 30-minute spontaneous breathing test (SBT), was used to validate the classification models. Patients were categorized into three clinical outcome groups: successful weaning (n = 132), failed weaning (n = 88), and reintubation within 48 hours after completion of the trial (n = 23). Features were selected using nonparametric statistical tests and correlation analysis, eliminating redundancy and retaining discriminative variables. Two machine learning (ML) classifiers, random forest and feedforward neural network, were designed to identify patients belonging to each of the three clinical outcome groups. Model performance was assessed using stratified hold-out cross-validation repeated over 150 iterations, with hyperparameters optimized using Bayesian methods. The random forest classifier using Poincar & eacute; descriptors achieved a mean accuracy of 90.4% and higher F1-scores across all groups, including those who required reintubation. These findings suggest that Poincar & eacute;-based variability metrics, in combination with ensemble learning, may enhance the accurate prediction of MV weaning outcomes in ARDS patients.
JTD Keywords: Heart-rate-variability, Mechanical ventilation,weaning,acute respiratory distress syndrome,poincar & eacute, Plot, Plot,mechanical ventilation,weaning,acute respiratory distress syndrome,poincar & eacute, Successful extubation
Elshof, J, Oppersma, E, Wisse, JJ, Bladder, G, Meijer, PM, Torres, A, Wijkstra, PJ, Duiverman, ML, (2024). Deventilation Syndrome in Patients with Chronic Obstructive Pulmonary Disease Using Nocturnal Noninvasive Ventilation: What Are the Underlying Mechanisms? RESPIRATION 10, 723-732
Introduction: Patients with chronic obstructive pulmonary disease (COPD) commonly experience severe dyspnea after discontinuation of nocturnal noninvasive ventilation (NIV), known as deventilation syndrome (DVS), which negatively affects quality of life. Despite various hypotheses, the precise mechanisms of DVS remain unknown. Methods: An observational pilot study was performed monitoring 16 stable COPD patients before, during, and after an afternoon nap on NIV. Seven patients experienced DVS (Borg Dyspnea Scale >= 5), while nine served as controls (Borg Dyspnea Scale
JTD Keywords: Asynchrony, Chronic obstructive pulmonary disease, Copd patients, Deventilation syndrom, Dyspnea, End-expiratory pressure, Exercise, Hyperinflation, Noninvasive ventilation, Patter
Mastrantuono, E, Ghibaudi, M, Matias, D, Battaglia, G, (2024). The multifaceted therapeutical role of low-density lipoprotein receptor family in high-grade glioma Molecular Oncology 18, 2966-2976
The diverse roles of the low-density lipoprotein receptor family (LDLR) have been associated with many processes critical to maintaining central nervous system (CNS) health and contributing to neurological diseases or cancer. In this review, we provide a comprehensive understanding of the LDLR's involvement in common brain tumors, specifically high-grade gliomas, emphasizing the receptors' critical role in the pathophysiology and progression of these tumors due to LDLR's high expression. We delve into LDLR's role in regulating cellular uptake and transport through the brain barrier. Additionally, we highlight LDLR's role in activating several signaling pathways related to tumor proliferation, migration, and invasion, engaging readers with an in-depth understanding of the molecular mechanisms at play. By synthesizing current research findings, this review underscores the significance of LDLR during tumorigenesis and explores its potential as a therapeutic target for high-grade gliomas. The collective insights presented here contribute to a deeper appreciation of LDLR's multifaceted roles and implications for physiological and pathological states, opening new avenues for tumor treatment. The role of LDLR family receptors in mediating the transport of LDL across the blood-brain barrier (BBB), facilitating processes such as survival, proliferation, and invasion in high-grade gliomas. Nanoparticles targeting LDLR can be used for drug delivery, potentially inducing cell death and reducing tumor proliferation and survival in high-grade glioma cells. image
JTD Keywords: Animals, Blood-brain-barrier, Brain neoplasms, Cancer, Delivery, Doxorubicin, Expression, Glioblastomas, Glioma, Humans, Low-density lipoprotein receptors, Low‐density lipoprotein receptors, Migratio, Nanoparticles, Neoplasm grading, Proliferation, Receptors, ldl, Signal transduction, Targeted therapie, Targeted therapies, Targeting therapy, Tumor microenvironment
Faure, LM, Gómez-González,, M, Baguer, O, Comelles, J, Martínez, E, Arroyo, M, Trepat, X, Roca-Cusachs, P, (2024). 3D Micropatterned Traction Force Microscopy: A Technique to Control 3D Cell Shape While Measuring Cell-Substrate Force Transmission Advanced Science 11, 2406932
Cell shape and function are intimately linked, in a way that is mediated by the forces exerted between cells and their environment. The relationship between cell shape and forces has been extensively studied for cells seeded on flat 2D substrates, but not for cells in more physiological 3D settings. Here, a technique called 3D micropatterned traction force microscopy (3D-mu TFM) to confine cells in 3D wells of defined shape, while simultaneously measuring the forces transmitted between cells and their microenvironment is demonstrated. This technique is based on the 3D micropatterning of polyacrylamide wells and on the calculation of 3D traction force from their deformation. With 3D-mu TFM, it is shown that MCF10A breast epithelial cells exert defined, reproducible patterns of forces on their microenvironment, which can be both contractile and extensile. Cells switch from a global contractile to extensile behavior as their volume is reduced are further shown. The technique enables the quantitative study of cell mechanobiology with full access to 3D cellular forces while having accurate control over cell morphology and the mechanical conditions of the microenvironment.
JTD Keywords: Cell volumes, Cytoskeleton, Durotaxis, Micro-wells, Myosi, Reveals, Traction force
Lodoso-Torrecilla, I, Konka, J, Kreuzer, M, Jimenez-Pique, E, Espanol, M, Ginebra, MP, (2024). Quality assessment of regenerated bone in intraosseous and intramuscular scaffolds by spectroscopy and nanoindentation BIOMATERIALS ADVANCES 164, 213982
The efficiency of synthetic bone grafts can be evaluated either in osseous sites, to analyze osteoconduction or ectopically, in intramuscular or subcutaneous sites, to assess osteoinduction. Bone regeneration is usually evaluated in terms of the presence and quantity of newly formed bone, but little information is normally provided on the quality of this bone. Here, we propose a novel approach to evaluate bone quality by the combined use of spectroscopy techniques and nanoindentation. Calcium phosphate scaffolds with different architectures, either foamed or 3D-printed, that were implanted in osseous or intramuscular defects in Beagle dogs for 6 or 12 weeks were analyzed. ATR-FTIR and Raman spectroscopy were performed, and mineral-to-matrix ratio, crystallinity, and mineral and collagen maturity were calculated and mapped for the newly regenerated bone and the mature cortical bone from the same specimen. For all the parameters studied, the newly-formed bone showed lower values than the mature host bone. Hardness and elastic modulus were determined by nanoindentation and, in line with what was observed by spectroscopy, lower values were observed in the regenerated bone than in the cortical bone. While, as expected, all techniques pointed to an increase in the maturity of the newly-formed bone between 6 and 12 weeks, the bone found in the intramuscular samples after 12 weeks presented lower mineralization than the intraosseous counterparts. Moreover, scaffold architecture also played a role in bone maturity, with the foamed scaffolds showing higher mineralization and crystallinity than the 3D-printed scaffolds after 12 weeks.
JTD Keywords: Atr-ftir, Bone regeneration, Calcium-phosphate, Ectopic implantation, Implant interface, In-vivo, Indentation, Mechanical-properties, Micromechanical properties, Nanoindentation, Orthotropic implantation, Raman spectroscop, Raman-spectroscopy, Strengt, Substitutes
van der Lande, GJM, Casas-Torremocha, D, Manasanch, A, Dalla Porta, L, Gosseries, O, Alnagger, N, Barra, A, Mejías, JF, Panda, R, Riefolo, F, Thibaut, A, Bonhomme, V, Thirion, B, Clasca, F, Gorostiza, P, Sanchez-Vives, MV, Deco, G, Laureys, S, Zamora-López, G, Annen, J, (2024). Brain state identification and neuromodulation to promote recovery of consciousness Brain Communications 6, fcae362
Experimental and clinical studies of consciousness identify brain states (i.e. quasi-stable functional cerebral organization) in a non-systematic manner and largely independent of the research into brain state modulation. In this narrative review, we synthesize advances in the identification of brain states associated with consciousness in animal models and physiological (sleep), pharmacological (anaesthesia) and pathological (disorders of consciousness) states of altered consciousness in humans. We show that in reduced consciousness the frequencies in which the brain operates are slowed down and that the pattern of functional communication is sparser, less efficient, and less complex. The results also highlight damaged resting-state networks, in particular the default mode network, decreased connectivity in long-range connections and especially in the thalamocortical loops. Next, we show that therapeutic approaches to treat disorders of consciousness, through pharmacology (e.g. amantadine, zolpidem), and (non-) invasive brain stimulation (e.g. transcranial direct current stimulation, deep brain stimulation) have shown partial effectiveness in promoting consciousness recovery. Although some features of conscious brain states may improve in response to neuromodulation, targeting often remains non-specific and does not always lead to (behavioural) improvements. The fields of brain state identification and neuromodulation of brain states in relation to consciousness are showing fascinating developments that, when integrated, might propel the development of new and better-targeted techniques for disorders of consciousness. We here propose a therapeutic framework for the identification and modulation of brain states to facilitate the interaction between the two fields. We propose that brain states should be identified in a predictive setting, followed by theoretical and empirical testing (i.e. in animal models, under anaesthesia and in patients with a disorder of consciousness) of neuromodulation techniques to promote consciousness in line with such predictions. This framework further helps to identify where challenges and opportunities lay for the maturation of brain state research in the context of states of consciousness. It will become apparent that one angle of opportunity is provided through the addition of computational modelling. Finally, it aids in recognizing possibilities and obstacles for the clinical translation of these diagnostic techniques and neuromodulation treatment options across both the multimodal and multi-species approaches outlined throughout the review.
JTD Keywords: (disorders of) consciousness, Anaesthesia, Animal model, Animal models, Area induces reanimation, Brain states, Direct-current stimulation, Disorder, Electrical-stimulation, Functional connectivity, General-anesthesia, Neuromodulation, Propofol-induced loss, Thalamic-stimulation, Transcranial magnetic stimulation, Vegetative state
Cicconofri, G, Blanco, P, Vilanova, G, Sáez, P, Arroyo, M, (2024). Active interfacial degradation/deposition of an elastic matrix by a fluid inclusion: Theory and pattern formation JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 191, 105773
During collective invasion in 3D, cohesive cellular tissues migrate within a fibrous extracellular matrix (ECM). This process requires significant remodeling of the ECM by cells, notably proteolysis at the cell-ECM interface by specialized molecules. Motivated by this problem, we develop a theoretical framework to study the dynamics of a fluid inclusion (modeling the cellular tissue) embedded in an elastic matrix (the ECM), which undergoes surface degradation/deposition. To account for the active nature of this process, we develop a continuum theory based on irreversible thermodynamics, leading to a kinetic relation for the degradation front that locally resembles the force-velocity relation of a molecular motor. We further study the effect of mechanotransduction on the stability of the cell-ECM interface, finding a variety of self- organized dynamical patterns of collective invasion. Our work identifies ECM proteolysis as an active process possibly driving the self-organization of cellular tissues.
JTD Keywords: Accretion, Accretion and erosion, Active matter, Cell-migration, Collective invasion, Growth, Insight, Irreversible thermodynamics, Mechanics, Model, Morphogenesis, Moving non-material interfaces, Pattern formatio, Proteolysis, Surface, Surface growth
Witzdam, L, White, T, Rodriguez-Emmenegger, C, (2024). Steps Toward Recapitulating Endothelium: A Perspective on the Next Generation of Hemocompatible Coatings MACROMOLECULAR BIOSCIENCE 24, 2400152
Endothelium, the lining in this blood vessel, orchestrates three main critical functions such as protecting blood components, modulating of hemostasis by secreting various inhibitors, and directing clot digestion (fibrinolysis) by activating tissue plasminogen activator. No other surface can perform these tasks; thus, the contact of blood and blood-contacting medical devices inevitably leads to the activation of coagulation, often causing device failure, and thromboembolic complications. This perspective, first, discusses the biological mechanisms of activation of coagulation and highlights the efforts of advanced coatings to recapitulate one characteristic of endothelium, hereafter single functions of endothelium and noting necessity of the synergistic integration of its three main functions. Subsequently, it is emphasized that to overcome the challenges of blood compatibility an endothelium-mimicking system is needed, proposing a synergy of bottom-up synthetic biology, particularly synthetic cells, with passive- and bioactive surface coatings. Such integration holds promise for developing advanced biomaterials capable of recapitulating endothelial functions, thereby enhancing the hemocompatibility and performance of blood-contacting medical devices. The activation of coagulation on the surface of blood-contacting medical devices often leads to thromboembolic complications. A concept for the next generation of hemocompatbile surfaces inspired by endothelium is proposed. This concept not only contribute to the fundamental understanding of hemocompatibility but also offer practical implications for the design and development of biomedical devices with enhanced biocompatibility and functionality. image
JTD Keywords: Animals, Antifouling coatings, Antifouling polymer brushes, Biocompatible materials, Blood coagulation, Coagulation-factor-xii, Coated materials, biocompatible, Endothelium, Endothelium, vascular, Endothelium-inspired, Endothelium‐inspired, Hemocompatibility, Hemocompatible surface coatings, Hemostasis, Heparin-induced thrombocytopenia, Humans, Nitric-oxide release, Of-the-art, Peptide macrocycle inhibitor, Plasma contact system, Protein-adsorption, Self-assembled monolayers, Surface modificatio, Synthetic endotheliu, Synthetic endothelium
Teulé-Trull, M, Demiquels-Punzano, E, Pérez, RA, Aparicio, C, Durán-Sindreu, F, Sanchez-López, E, González-Sánchez, JA, Delgado, LM, (2024). Revision of ex vivo endodontic biofilm model using computer aided design JOURNAL OF DENTISTRY 149, 105270
Objective: Most endodontic diseases are bacterium-mediated inflammatory or necrotic process induced by contaminated dental pulp. Although great advances are being performed to obtain more efficient antibacterial strategies for persistent infections, most studies lack of representative models to test their antibacterial effects and their outcomes cannot be promptly translated to clinical practice. Therefore, this study aimed to refine an ex vivo endodontic biofilm model combining human tooth, computer guided design and 3D printing to obtain a more reproducible and predictable model. Methods: Monoradicular teeth were cut using three different methods: hand-held (HCC), mechanical precision (MPC) and computer aid guided cutting (CGC). Then, blocks were reassembled. The different model preparations were assessed in terms of dimensional tolerance, surface analysis, liquid tightness and Enterococcus faecalis biofilm development for 21 days, which was studied by metabolic assays and confocal microscopy. Then, the proposed model was validated using different commercial disinfecting treatments. Results: CGC exhibited significantly lower deviation and surface without defects compared to HHC and MPC, leading to superior liquid tightness. Similarly, mature biofilms with high metabolic activity and vitality were observed in all conditions, CGC showing the lowest variation. Regarding the model validation, all antibacterial treatments resulted in the complete eradication of bacteria in the standard 2D model, whereas commercial treatments exhibited varying levels of efficacy in the proposed ex vivo model, from moderately reduction of metabolic activity to complete elimination of biofilm. Conclusions: The novel guided approach represents a more reliable, standardized, and reproducible model for the evaluation of endodontic disinfecting therapies. Clinical Significance: During antibacterial treatment development, challenging 3D models using teeth substrates to test antibacterial treatments novel guided approach represents a more reliable, standardized, and reproducible model for the evaluation of endodontic disinfecting therapies.
JTD Keywords: 3d printin, Bacteria, Biofilm, Computer-aided manufacturing, Dental model, Dentin, Efficacy, Endodontics, Enterococcus faecalis, Enterococcus-faecalis, Irrigation, Protocols, Removal, Resistance, Susceptibility, Syste
Garcia-de-Albeniz, N, Hodásová, L, Buxadera-Palomero, J, Jiménez-Piqué, E, Ginebra, MP, Llanes, L, Alemán, C, Armelin, E, Mas-Moruno, C, Fargas, G, (2024). Peptidic biofunctionalization of infiltrated zirconia scaffolds produced by direct ink writing CERAMICS INTERNATIONAL 50, 36993-37001
Porous zirconia scaffolds manufactured using polymer-infiltrated ceramic network (PICN) and additive manufacturing technologies are emerging as promising alternatives to traditional ceramic materials in dental restorations. However, incomplete osseointegration and bacterial infections still represent challenges for the long-term performance of this new composite material. To address this, the present study aims to investigate the effect of peptide biofunctionalization on the biological performance of infiltrated zirconia scaffold surfaces. The samples used in the work consisted of a 3D-printed zirconia scaffold infiltrated with a dimethacrylate copolymer. Surface biofunctionalization was achieved using a synthetic platform containing the cell-adhesive sequence RGD and the antibacteria LF1-11 peptide (RGD-LF). The attachment of the molecule was characterized through fluorescence confocal laser scanning microscopy and X-ray photoelectron spectroscopy. The biological performance of the samples was evaluated in terms of human mesenchymal stem cell adhesion and early attachment of S. aureus. The physicochemical characterization verified the successful anchoring of the biomolecule to the surface, leading to a peptide density of 288 pmol/cm2. 2 . The biological assays confirmed the potential of RGD-LF to improve cell adhesion and spreading. In this sense, the average cell area increased fourfold in the biofunctionalized surface. Regarding bacterial adhesion, it was demonstrated that RGD-LF significantly inhibited it, reducing early adhesion by half compared to the untreated surface. Overall, this study provides valuable insights into the biofunctionalization of polymer-infiltrated 3D scaffolds for the development of cell-instructive and antibacterial surfaces tailored for dental applications.
JTD Keywords: Antibacteria, Biocompatibility, Cell adhesion, Composite, Dental ceramics, Direct ink writing, Fabrication, Infiltrated zirconia scaffolds, Mechanical-properties, Peptide biofunctionalization, Picn material, Strength, Surface, Topograph, Wear behavior
Rossetti, L, Grosser, S, Abenza, JF, Valon, L, Roca-Cusachs, P, Alert, R, Trepat, X, (2024). Optogenetic generation of leader cells reveals a force-velocity relation for collective cell migration Nature Physics 20, 1659-1669
During development, wound healing and cancer invasion, migrating cell clusters feature highly protrusive leader cells at their front. Leader cells are thought to pull and direct their cohort of followers, but whether their local action is enough to guide the entire cluster, or if a global mechanical organization is needed, remains controversial. Here we show that the effectiveness of the leader-follower organization is proportional to the asymmetry of traction and tension within cell clusters. By combining hydrogel micropatterning and optogenetic activation, we generate highly protrusive leaders at the edge of minimal cell clusters. We find that the induced leader can robustly drag one follower but not larger groups. By measuring traction forces and tension propagation in clusters of increasing size, we establish a quantitative relationship between group velocity and the asymmetry of the traction and tension profiles. Modelling motile clusters as active polar fluids, we explain this force-velocity relationship in terms of asymmetries in the active traction profile. Our results challenge the notion of autonomous leader cells, showing that collective cell migration requires global mechanical organization within the cluster. Leader cells play an important role in guiding migratory clusters in various biological processes. Now, the mechanical organization of leader and followers within a cell cluster is shown to enable collective migration.
JTD Keywords: Driven, Dynamics, Guidance, Require
Sala-Jarque, Julia, Gil, Vanessa, Andres-Benito, Pol, Martinez-Soria, Ines, Picon-Pages, Pol, Hernandez, Felix, Avila, Jesus, Luis Lanciego, Jose, Nuvolone, Mario, Aguzzi, Adriano, Gavin, Rosalina, Ferrer, Isidro, Antonio del Rio, Jose, (2024). The cellular prion protein does not affect tau seeding and spreading of sarkosyl-insoluble fractions from Alzheimer's disease Scientific Reports 14, 21622
The cellular prion protein (PrP (c)) plays many roles in the developing and adult brain. In addition, PrP (c) binds to several amyloids in oligomeric and prefibrillar forms and may act as a putative receptor of abnormal misfolded protein species. The role of PrP (c) in tau seeding and spreading is not known. In the present study, we have inoculated well-characterized sarkosyl-insoluble fractions of sporadic Alzheimer's disease (sAD) into the brain of adult wild-type mice (Prnp(+/+)), Prnp(0/0) (ZH3 strain) mice, and mice over-expressing the secreted form of PrP (c) lacking their GPI anchor (Tg44 strain). Phospho-tau (ptau) seeding and spreading involving neurons and oligodendrocytes were observed three and six months after inoculation. 3Rtau and 4Rtau deposits from the host tau, as revealed by inoculating Mapt(0/0) mice and by using specific anti-mouse and anti-human tau antibodies suggest modulation of exon 10 splicing of the host mouse Mapt gene elicited by exogenous sAD-tau. However, no tau seeding and spreading differences were observed among Prnp genotypes. Our results show that PrP (c) does not affect tau seeding and spreading in vivo.
JTD Keywords: Alpha-synuclein, Alzheimer disease, Alzheimer's disease, Alzheimer’s disease, Amyloid-beta oligomers, Animals, Brain, Disease models, animal, Expression, Humans, Impairmen, Mapt, Mice, Mice, transgenic, Neurons, Paired helical filaments, Pathological tau, Prion proteins, Prnp, Prnp protein, mouse, Propagation, Prp (c), Prpc, Prpc proteins, Sarcosine, Sarkosyl, Seeding, Spreadin, Spreading, Synaptic plasticity, Tau, Tau proteins, Tauopathies
González, H, Arizmendi, CJ, Giraldo, BF, (2024). Development of a Deep Learning Model for the Prediction of Ventilator Weaning International Journal Of Online And Biomedical Engineering 20, 161-178
The issue of failed weaning is a critical concern in the intensive care unit (ICU) setting. This scenario occurs when a patient experiences difficulty maintaining spontaneous breathing and ensuring a patent airway within the first 48 hours after the withdrawal of mechanical ventilation. Approximately 20% of ICU patients experience this phenomenon, which has severe repercussions on their health. It also has a substantial impact on clinical evolution and mortality, which can increase by 25% to 50%. To address this issue, we propose a medical support system that uses a convolutional neural network (CNN) to assess a patient's suitability for disconnection from a mechanical ventilator after a spontaneous breathing test (SBT). During SBT, respiratory flow and electrocardiographic activity were recorded and after processed using time-frequency analysis (TFA) techniques. Two CNN architectures were evaluated in this study: one based on ResNet50, with parameters tuned using a Bayesian optimization algorithm, and another CNN designed from scratch, with its structure also adapted using a Bayesian optimization algorithm. The WEANDB database was used to train and evaluate both models. The results showed remarkable performance, with an average accuracy 98 +/- 1.8% when using CNN from scratch. This model has significant implications for the ICU because it provides a reliable tool to enhance patient care by assisting clinicians in making timely and accurate decisions regarding weaning. This can potentially reduce the adverse outcomes associated with failed weaning events.
JTD Keywords: Bayesian optimization algorithm (boa, Continuous wavelet transform (cwt), Convolutional, Extubation, Failur, Intensive-care-unit, Neural network (cnn) from scratch, Respiratory-distress-syndrome, Time-frequency analysis (tfa), Weaning
Sharma, P, Venugopal, A, Verdi, CM, Roger, MS, Calò, A, Kumar, M, (2024). Heparin binding induced supramolecular chirality into the self-assembly of perylenediimide bolaamphiphile Journal of Materials Chemistry B 12, 7292-7297
Chirality is one of the hallmarks of biomolecules. Herein, we utilize heparin, a chiral biomolecule and potent drug, to induce chiral organization into the assembly of an achiral molecule. Polyanionic heparin binds with a dicationic perylenediimide derivative to induce supramolecular helical organization in aqueous medium as well as in a highly competitive cell culture medium. Heparin, an anionic chiral biomolecule, binds to cationic achiral perylenediimide derivative to induce supramolecular helicity, forming chiral nanostructures in both aqueous and cell culture medium.
JTD Keywords: Circularly-polarized luminescence, Dichroism, Nanotubes, Polymers, Stack
Yuan, SC, Alvarez, Z, Lee, SR, Pavlovic, RZ, Yuan, CH, Singer, E, Weigand, SJ, Palmer, LC, Stupp, SI, (2024). Supramolecular Motion Enables Chondrogenic Bioactivity of a Cyclic Peptide Mimetic of Transforming Growth Factor-β1 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 146, 21555-21567
Transforming growth factor (TGF)-beta 1 is a multifunctional protein that is essential in many cellular processes that include fibrosis, inflammation, chondrogenesis, and cartilage repair. In particular, cartilage repair is important to avoid physical disability since this tissue does not have the inherent capacity to regenerate beyond full development. We report here on supramolecular coassemblies of two peptide amphiphile molecules, one containing a TGF-beta 1 mimetic peptide, and another which is one of two constitutional isomers lacking bioactivity. Using human articular chondrocytes, we investigated the bioactivity of the supramolecular copolymers of each isomer displaying either the previously reported linear form of the mimetic peptide or a novel cyclic analogue. Based on fluorescence depolarization and H-1 NMR spin-lattice relaxation times, we found that coassemblies containing the cyclic compound and the most dynamic isomer exhibited the highest intracellular TGF-beta 1 signaling and gene expression of cartilage extracellular matrix components. We conclude that control of supramolecular motion is emerging as an important factor in the binding of synthetic molecules to receptors that can be tuned through chemical structure.
JTD Keywords: Amphiphile, Cartilage, Chondrocytes, Chondrogenesis, Growth-factor-beta, Humans, Knee osteoarthritis, Neutralization, Peptides, cyclic, Progenitor cells, Repair, Scaffolds, Spectroscop, Tissue, Transforming growth factor beta1
del-Mazo-Barbara, Laura, Diez-Escudero, Anna, Lodoso-Torrecilla, Irene, Aramesh, Morteza, Persson, Cecilia, Ginebra, Maria-Pau, (2024). Direct ink writing of biomimetic hydroxyapatite scaffolds with tailored concave porosity International Journal of Bioprinting 10, 224-244
Direct ink writing (DIW) is a promising technology for the fabrication of personalized bone grafts, as it enables the customization of their geometrical conformation with high reproducibility and is compatible with the use of self-setting calcium-deficient hydroxyapatite inks. However, the scaffolds obtained by DIW consist mostly of convex filaments, which is a limitation since concave surfaces are known to promote bone regeneration in vivo. In this work, we explore the use of triply periodic minimal surface (TPMS) designs in DIW of calcium phosphate self-hardening inks as a strategy to obtain scaffolds with controlled concave macropores. The limitations of the printing parameters with high ceramic-loaded inks using DIW resulted in only 20% nominal porosity for gyroid-, diamond-, and Schwarz-based structures. The inherent layered pores from TPMS geometries enabled concavities typically unattainable via DIW, bearing substantial implications for subsequent osteoinductive capabilities. Although the mechanical properties were lower in the TPMS-based scaffolds than in the orthogonal patterned ones, the blood permeability of TPMS-based structures was higher. The concave pore architecture enhanced the osteogenic potential of the and mineralization.
JTD Keywords: Alkaline-phosphatase, Biomimetic hydroxyapatite, Biomorphic structures, Blood analog fluid, Bone, Bone scaffold, Concavity, Defects, Direct ink writing, Mineralization, Minimal-surfaces, Permeability, Pore architectur, Shap, Stress, Tissue
Morales, J, Almazán, DB, Catthoor, F, Groenendaal, W, Jané, R, (2024). Validation of a novel wearable device to estimate heart rate variability and cardiorespiratory indexes 2024 IEEE INTERNATIONAL SYMPOSIUM ON MEDICAL MEASUREMENTS AND APPLICATIONS, MEMEA 2024
Heart rate variability and cardiorespiratory coupling parameters show great potential in offering insights for the assessment and follow-up of patients with different conditions and diseases. The continual acquisition of these parameters would facilitate the ongoing evaluation of patients dealing with various health issues. In this work, we demonstrate the usability of a novel wearable device, the Digipredict Physiopatch, for estimating heart rate variability parameters in the frequency domain and a measure of cardiorespiratory coupling continuously. Signals recorded with the wearable and a Biopac benchtop system were utilized to calculate these parameters. We evaluate differences in the results obtained from the signals of the two devices. The results reveal three distinct aspects. Firstly, the values obtained with the Digipredict Physiopatch are, in general, not significantly different from the ones estimated with the Biopac system. Secondly, we illustrate that it is possible to estimate the cardiorespiratory index using the respiratory signals from the wearable, acquired through bioimpedance. This result validates the use of bioimpedance recorded with Digipredict Physiopatch as an alternative method for acquiring respiratory signals in wearable devices. Thirdly, the cardiorespiratory parameter evaluated in this work appears to be more robust to movement artifacts compared to the heart rate variability parameters due to the inclusion of respiratory information in the algorithms.
JTD Keywords: Cardiorespiratory coupling, Heart rate variabilit, Human, Respiratory sinus arrhythmia, Wearable devices
Dhawan, U, Williams, JA, Windmill, JFC, Childs, P, Gonzalez-Garcia, C, Dalby, MJ, Salmeron-Sanchez, M, (2024). Engineered Surfaces That Promote Capture of Latent Proteins to Facilitate Integrin-Mediated Mechanical Activation of Growth Factors ADVANCED MATERIALS 36, 2310789
Conventional osteogenic platforms utilize active growth factors to repair bone defects that are extensive in size, but they can adversely affect patient health. Here, an unconventional osteogenic platform is reported that functions by promoting capture of inactive osteogenic growth factor molecules to the site of cell growth for subsequent integrin-mediated activation, using a recombinant fragment of latent transforming growth factor beta-binding protein-1 (rLTBP1). It is shown that rLTBP1 binds to the growth-factor- and integrin-binding domains of fibronectin on poly(ethyl acrylate) surfaces, which immobilizes rLTBP1 and promotes the binding of latency associated peptide (LAP), within which inactive transforming growth factor beta 1 (TGF-beta 1) is bound. rLTBP1 facilitates the interaction of LAP with integrin beta 1 and the subsequent mechanically driven release of TGF-beta 1 to stimulate canonical TGF-beta 1 signaling, activating osteogenic marker expression in vitro and complete regeneration of a critical-sized bone defect in vivo. An osteogenic platform that functions by capturing inactive growth factor molecules is engineered to overcome conventional challenges associated with the use of active growth factors. The platform triggers capture of inactive transforming growth factor beta-1 for its subsequent integrin-mediated activation which activates osteogenic downstream signaling in vitro and fully repairs critical-sized bone defect in vivo. image
JTD Keywords: Animals, Bone, Bone defect, Bone regeneration, Cell proliferation, Cells, Chemical activation, Defects, Differentiation, Fibronectin, Fibronectins, Growth factor, Growth factors, Humans, Integrin beta1, Integrins, Latency associated peptides, Latent tgf-beta binding proteins, Ltbp1, Osteogenesis, Osteogenic, Protein binding, Recombinant proteins, Release, Repair, Signal transduction, Surface properties, Tgf-beta, Tgf-β1, Transforming growth factor beta1, Transforming growth factors
Pankratov, D, Martinez, SH, Karman, C, Gerzhik, A, Gomila, G, Trashin, S, Boschker, HTS, Geelhoed, JS, Mayer, D, De Wael, K, Meysman, FJR, (2024). The organo-metal-like nature of long-range conduction in cable bacteria BIOELECTROCHEMISTRY 157, 108675
Cable bacteria are filamentous, multicellular microorganisms that display an exceptional form of biological electron transport across centimeter-scale distances. Currents are guided through a network of nickel-containing protein fibers within the cell envelope. Still, the mechanism of long-range conduction remains unresolved. Here, we characterize the conductance of the fiber network under dry and wet, physiologically relevant, conditions. Our data reveal that the fiber conductivity is high (median value: 27 S cm-1; range: 2 to 564 S cm-1), does not show any redox signature, has a low thermal activation energy (Ea = 69 +/- 23 meV), and is not affected by humidity or the presence of ions. These features set the nickel-based conduction mechanism in cable bacteria apart from other known forms of biological electron transport. As such, conduction resembles that of an organic semi-metal with a high charge carrier density. Our observation that biochemistry can synthesize an organometal-like structure opens the way for novel bio-based electronic technologies.
JTD Keywords: 'current, Activation energy, Bacteria, Bioelectronic, Bioelectronics, Cable bacteria, Cables, Centimeter-scale, Electrochemical impedance spectroscopy, Electrochemical-impedance spectroscopies, Electron transport, Electron transport properties, Electron-transport, Long -distance electron transport, Long-distance electron transport, Microbial nanowires, Nickel, Nickel containing, Protein conductivity, Protein fibers, Proteins, Sulfur
Jácome, D, Cotrufo, T, Andrés-Benito, P, Lidón, L, Martí, E, Ferrer, I, del Río, JA, Gavín, R, (2024). miR-519a-3p, found to regulate cellular prion protein during Alzheimer 's disease pathogenesis, as a biomarker of asymptomatic stages BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR BASIS OF DISEASE 1870, 167187
Clinical relevance of miRNAs as biomarkers is growing due to their stability and detection in biofluids. In this, diagnosis at asymptomatic stages of Alzheimer ' s disease (AD) remains a challenge since it can only be made at autopsy according to Braak NFT staging. Achieving the objective of detecting AD at early stages would allow possible therapies to be addressed before the onset of cognitive impairment. Many studies have determined that the expression pattern of some miRNAs is dysregulated in AD patients, but to date, none has been correlated with downregulated expression of cellular prion protein (PrP C ) during disease progression. That is why, by means of cross studies of miRNAs up -regulated in AD with in silico identification of potential miRNAs-binding to 3 ' UTR of human PRNP gene, we selected miR-519a-3p for our study. Then, in vitro experiments were carried out in two ways. First, we validated miR-519a-3p target on 3 ' UTR- PRNP , and second, we analyzed the levels of PrP C expression after using of mimic technology on cell culture. In addition, RT-qPCR was performed to analyzed miR519a-3p expression in human cerebral samples of AD at different stages of disease evolution. Additionally, samples of other neurodegenerative diseases such as other non -AD tauopathies and several synucleinopathies were included in the study. Our results showed that miR-519a-3p overlaps with PRNP 3 ' UTR in vitro and promotes downregulation of PrP C . Moreover, miR-519a-3p was found to be up -regulated exclusively in AD samples from stage I to VI, suggesting its potential use as a novel label of preclinical stages of the disease.
JTD Keywords: 3' untranslated regions, Activation, Aged, Aged, 80 and over, Alzheimer disease, Alzheimer's disease, Biomarke, Biomarker, Biomarkers, Brain, Cellular prion protein, Developmental expression, Female, Gen, Humans, Male, Micrornas, Mirn519 microrna, human, Plasma, Prion proteins, Prnp protein, human, Prpc, Prpc proteins, Tau-aggregation
Monteil, VM, Wright, SC, Dyczynski, M, Kellner, MJ, Appelberg, S, Platzer, SW, Ibrahim, A, Kwon, H, Pittarokoilis, I, Mirandola, M, Michlits, G, Devignot, S, Elder, E, Abdurahman, S, Bereczky, S, Bagci, B, Youhanna, S, Aastrup, T, Lauschke, VM, Salata, C, Elaldi, N, Weber, F, Monserrat, N, Hawman, DW, Feldmann, H, Horn, M, Penninger, JM, Mirazimi, A, (2024). Crimean-Congo haemorrhagic fever virus uses LDLR to bind and enter host cells Nature Microbiology 9, 1499-1512
Climate change and population densities accelerated transmission of highly pathogenic viruses to humans, including the Crimean-Congo haemorrhagic fever virus (CCHFV). Here we report that the Low Density Lipoprotein Receptor (LDLR) is a critical receptor for CCHFV cell entry, playing a vital role in CCHFV infection in cell culture and blood vessel organoids. The interaction between CCHFV and LDLR is highly specific, with other members of the LDLR protein family failing to bind to or neutralize the virus. Biosensor experiments demonstrate that LDLR specifically binds the surface glycoproteins of CCHFV. Importantly, mice lacking LDLR exhibit a delay in CCHFV-induced disease. Furthermore, we identified the presence of Apolipoprotein E (ApoE) on CCHFV particles. Our findings highlight the essential role of LDLR in CCHFV infection, irrespective of ApoE presence, when the virus is produced in tick cells. This discovery holds profound implications for the development of future therapies against CCHFV. Laboratory and clinical strains of Crimean-Congo haemorrhagic fever virus use LDLR to bind and enter host cells in blood vessel organoids and mice. Infection can also occur through ApoE, possibly present on virus particles.
JTD Keywords: Cholesterol, Clathrin, Entry requires, Genetics, Localization, Protei, Receptor
Brewer, MK, Torres, P, Ayala, V, Portero-Otin, M, Pamplona, R, Andrés-Benito, P, Ferrer, I, Guinovart, JJ, Duran, J, (2024). Glycogen accumulation modulates life span in a mouse model of amyotrophic lateral sclerosis JOURNAL OF NEUROCHEMISTRY 168, 744-759
Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by the progressive loss of motor neurons in the spinal cord. Glial cells, including astrocytes and microglia, have been shown to contribute to neurodegeneration in ALS, and metabolic dysfunction plays an important role in the progression of the disease. Glycogen is a soluble polymer of glucose found at low levels in the central nervous system that plays an important role in memory formation, synaptic plasticity, and the prevention of seizures. However, its accumulation in astrocytes and/or neurons is associated with pathological conditions and aging. Importantly, glycogen accumulation has been reported in the spinal cord of human ALS patients and mouse models. In the present work, using the SOD1G93A mouse model of ALS, we show that glycogen accumulates in the spinal cord and brainstem during symptomatic and end stages of the disease and that the accumulated glycogen is associated with reactive astrocytes. To study the contribution of glycogen to ALS progression, we generated SOD1G93A mice with reduced glycogen synthesis (SOD1G93A GShet mice). SOD1G93A GShet mice had a significantly longer life span than SOD1G93A mice and showed lower levels of the astrocytic pro-inflammatory cytokine Cxcl10, suggesting that the accumulation of glycogen is associated with an inflammatory response. Supporting this, inducing an increase in glycogen synthesis reduced life span in SOD1G93A mice. Altogether, these results suggest that glycogen in reactive astrocytes contributes to neurotoxicity and disease progression in ALS.© 2023 The Authors. Journal of Neurochemistry published by John Wiley & Sons Ltd on behalf of International Society for Neurochemistry.
JTD Keywords: activation, astrocytes, brain, contributes, expression, glycogen, impairment, mice, motor neurons, neurodegeneration, reactive astrocytes, spinal cord, Amyotrophic lateral sclerosis, Astrocytes, Glycogen, Motor neurons, Motor-neuron degeneration, Neurodegeneration, Spinal cord
Arnau, M, Sans, J, Gallego, E, Peraales, JF, Turon, P, Alemán, C, (2024). Polarized hydroxyapatite, a ceramic nanocatalyst to convert automotive carbon emissions into ethanol Journal of Environmental Chemical Engineering 12, 112255
This paper is aimed to develop ultrananoporous polarized hydroxyapatite (HAp) catalyst and evaluate its per-formance in transforming CO2 into useable ethanol considering three different scenarios: 1) a batch reaction using a mixture of CO2 and CH4 as feeding gas; 2) a batch reaction using as reactant exhaust gases captured from the fumes of diesel vehicles; and 3) a continuous flow reaction using pure CO2 as feeding gas. Ultrananoporous HAp scaffolds were prepared using a four-step process: 1) as prepared HAp powder was mixed with 60% wt. of a commercial hydrogel at low-temperature; 2) the resulting paste was shaped at low temperature to reduce the adhesion between the metallic tools and the mixture, enhancing the homogeneity of the sample; 3) the shaped paste was calcined in air by applying 1000 oC during 2 h to eliminate the hydrogel; and 4) an external DC electric field of 3 kV/cm was imposed at 1000 oC during 1 h to the calcined scaffold. The resulting polarized scaffolds both ultrananoporosity and catalytic activation. Thus, the mass: volume ratio of the ultrananoporous catalyst was much lower than that of conventional HAp catalyst (718 vs 5093 g/L. Furthermore, the ethanol yield was much higher (up to a factor of x21.4) for the ultrananoporous catalyst than for the compact one, allowing us to conclude that ultrananoporous polarized HAp catalyst is a promising technology for transforming CO2 into valuable chemical products from highly polluted gases, especially those coming from road, sea and air transport.
JTD Keywords: A: ceramics, Air pollution, Automotives, Batch reactions, Calcination, Carbon, Carbon dioxide, Co2 fixation, Co2 reduction, Desig, Electric fields, Environmental process, Ethanol, Exhaust gases, Feeding gas, Fumes, Hydrogels, Hydroxyapatite, Lows-temperatures, Nano-catalyst, Nanocatalysts, Polarized catalys, Polarized catalyst, Scaffolds, Temperature, ]+ catalyst
Chen, SQ, Prado-Morales, C, Sánchez-deAlcázar, D, Sánchez, S, (2024). Enzymatic micro/nanomotors in biomedicine: from single motors to swarms Journal of Materials Chemistry B 12, 2711-2719
Micro/nanomotors (MNMs) have evolved from single self-propelled entities to versatile systems capable of performing one or multiple biomedical tasks. When single MNMs self-assemble into coordinated swarms, either under external control or triggered by chemical reactions, they offer advantages that individual MNMs cannot achieve. These benefits include intelligent multitasking and adaptability to changes in the surrounding environment. Here, we provide our perspective on the evolution of MNMs, beginning with the development of enzymatic MNMs since the first theoretical model was proposed in 2005. These enzymatic MNMs hold immense promise in biomedicine due to their advantages in biocompatibility and fuel availability. Subsequently, we introduce the design and application of single motors in biomedicine, followed by the control of MNM swarms and their biomedical applications. In the end, we propose viable solutions for advancing the development of MNM swarms and anticipate valuable insights into the creation of more intelligent and controllable MNM swarms for biomedical applications.; Micro/nanomotor swarms propelled by diverse mechanisms.
JTD Keywords: Active particles, Actuation, Behaviors, Biocompatibility, Biomedical applications, Coordination reactions, Design and application, Diffusion, External control, Medical applications, Micromotors, Motion, Nanomotors, Powered nanomotors, Propulsion, Self-assemble, Surrounding environment, Theoretical modeling, Versatile system, Viable solutions
Husser, Clara, Kwon, Hyesoo, Andersson, Klara, Appelberg, Sofia, Montserrat, Nuria, Mirazimi, Ali, Monteil, Vanessa M, Monteil, Vanessa M, (2024). P53-Independent G1-Cell Cycle Arrest Increases SARS-CoV-2 RNA Replication Microorganisms 12, 443
While having already killed more than 7 million of people worldwide in 4 years, SARS-CoV-2, the etiological agent of COVID-19, is still circulating and evolving. Understanding the pathogenesis of the virus is of capital importance. It was shown that in vitro and in vivo infection with SARS-CoV-2 can lead to cell cycle arrest but the effect of the cell cycle arrest on the virus infection and the associated mechanisms are still unclear. By stopping cells in the G1 phase as well as targeting several pathways involved using inhibitors and small interfering RNAs, we were able to determine that the cell cycle arrest in the late G1 is beneficial for SARS-CoV-2 replication. This cell cycle arrest is independent of p53 but is dependent on the CDC25A-CDK2/cyclin E pathway. These data give a new understanding in SARS-CoV-2 pathogenesis and highlight some possible targets for the development of novel therapeutic approaches.
JTD Keywords: Cell lung-cancer,exchanger nhe,g1 phase,proliferation,inhibitio, Covid-19,coronavirus,pathogenicity,replication,cdk2,cyclin e,cdc25a,treatment
Hafa, L, Breideband, L, Posada, LR, Torras, N, Martinez, E, Stelzer, EHK, Pampaloni, F, (2024). Light Sheet-Based Laser Patterning Bioprinting Produces Long-Term Viable Full-Thickness Skin Constructs ADVANCED MATERIALS 36, e2306258
Tissue engineering holds great promise for biomedical research and healthcare, offering alternatives to animal models and enabling tissue regeneration and organ transplantation. Three-dimensional (3D) bioprinting stands out for its design flexibility and reproducibility. Here, we present an integrated fluorescent light sheet bioprinting and imaging system that combines high printing speed (0.66 mm3 /s) and resolution (9 μm) with light sheet-based imaging. This approach employs direct laser patterning and a static light sheet for confined voxel crosslinking in photocrosslinkable materials. The developed bioprinter enables real-time monitoring of hydrogel crosslinking using fluorescent recovery after photobleaching (FRAP) and brightfield imaging as well as in situ light sheet imaging of cells. Human fibroblasts encapsulated in a thiol-ene click chemistry-based hydrogel exhibited high viability (83% ± 4.34%) and functionality. Furthermore, full-thickness skin constructs displayed characteristics of both epidermal and dermal layers and remained viable for 41 days. The integrated approach demonstrates the capabilities of light sheet bioprinting, offering high speed, resolution, and real-time characterization. Future enhancements involving solid-state laser scanning devices such as acousto-optic deflectors and modulators will further enhance resolution and speed, opening new opportunities in light-based bioprinting and advancing tissue engineering. This article is protected by copyright. All rights reserved.This article is protected by copyright. All rights reserved.
JTD Keywords: cadherin, collagen, culture, differentiation, fluorescence microscopy, full-thickness skin model, hydrogels, light sheet bioprinter, light sheet fluorescence microscopy, proliferation, survival, tissue engineering, Animal, Animals, Biofabrication, Bioprinting, Cell culture, Crosslinking, Fluorescence, Fluorescence microscopy, Full-thickness skin model, Hair follicle, Human, Humans, Hydrogel, Hydrogels, Image resolution, Laser patterning, Light sheet, Light sheet bioprinter, Light sheet fluorescence microscopy, Molecular biology, Photobleaching, Printing, three-dimensional, Procedures, Reproducibility, Reproducibility of results, Skin model, Three dimensional printing, Tissue, Tissue engineering, Tissue regeneration, Tissue scaffolds, Tissues engineerings
Farré, R, Rodríguez-Lázaro, MA, Otero, J, Gavara, N, Sunyer, R, Farré, N, Gozal, D, Almendros, I, (2024). Low-cost, open-source device for simultaneously subjecting rodents to different circadian cycles of light, food, and temperature Frontiers in Physiology 15, 1356787
Exposure of experimental rodents to controlled cycles of light, food, and temperature is important when investigating alterations in circadian cycles that profoundly influence health and disease. However, applying such stimuli simultaneously is difficult in practice. We aimed to design, build, test, and open-source describe a simple device that subjects a conventional mouse cage to independent cycles of physiologically relevant environmental variables. The device is based on a box enclosing the rodent cage to modify the light, feeding, and temperature environments. The device provides temperature-controlled air conditioning (heating or cooling) by a Peltier module and includes programmable feeding and illumination. All functions are set by a user-friendly front panel for independent cycle programming. Bench testing with a model simulating the CO2 production of mice in the cage showed: a) suitable air renewal (by measuring actual ambient CO2), b) controlled realistic illumination at the mouse enclosure (measured by a photometer), c) stable temperature control, and d) correct cycling of light, feeding, and temperature. The cost of all the supplies (retail purchased by e-commerce) was <300 US$. Detailed technical information is open-source provided, allowing for any user to reliably reproduce or modify the device. This approach can considerably facilitate circadian research since using one of the described low-cost devices for any mouse group with a given light-food-temperature paradigm allows for all the experiments to be performed simultaneously, thereby requiring no changes in the light/temperature of a general-use laboratory. 1 Introduction
JTD Keywords: Animal experiment, Animal model, Animal research, Article, Circadian alteration, Circadian rhythm, Commercial phenomena, Controlled study, Cycling, Energy consumption, Energy-expenditure, Experimental model, Feeding, Food, Food availability, Illumination, Intermittent fasting, Light, Light cycle, Light dark cycle, Mouse, Nonhuman, Open source technology, Open-source hardware, Performance, Photography, Research, Rhythms, Rodent, Temperature, Temperature cycle
Sans, Jordi, Arnau, Marc, Bosque, Ricard, Turon, Pau, Aleman, Carlos, (2024). Synthesis of urea from CO2 and N2 fixation under mild conditions using polarized hydroxyapatite as a catalyst Sustainable Energy & Fuels 8, 1473-1482
Polarized hydroxyapatite (p-HAp) has been used as a catalyst for the synthesis of urea coupling N-2, CO2 and water under mild reaction conditions when compared to classical nitrogen fixation reactions, such as the Haber-Bosch process. The reaction of 3 bar of N-2 and 3 bar of CO2 under UV illumination at 120 degrees C (for 48 h) results in a urea yield of 1.5 +/- 0.1 mmol per gram of catalyst (g(c)) with a selectivity close to 80%, whereas the reaction is not successful without UV irradiation. However, the addition of small amounts of NO (314 ppm) produces 15.2 +/- 0.6 and 4.6 +/- 0.4 mmol g(c)(-1) with and without UV illumination, respectively, with the selectivity in both cases being close to 100%. As nitrogen fixation without UV irradiation using p-HAp as a catalyst is a challenge, studies with NO have been conducted varying the reaction conditions (time, pressure and temperature). The results suggest a mechanism based on the production of NH4+ through the oxidation of N-2.
JTD Keywords: Carbon dioxide, Carbon,dinitrogen,reduction,nitrogen,ammonia,dioxid, Catalyst selectivity, Condition, Haber-bosch process, Hydroxyapatite, Irradiation, Metabolism, Mild reaction conditions, Nitrogen fixation, Pressure and temperature, Reaction conditions, Time pressures, Time-temperature, Urea, Uv illuminations, Without uv irradiations, ]+ catalyst
Pahuja, A, Corredera, IG, Moya-Rull, D, Garreta, E, Montserrat, N, (2024). Engineering physiological environments to advance kidney organoid models from human pluripotent stem cells CURRENT OPINION IN CELL BIOLOGY 86, 102306
During embryogenesis, the mammalian kidney arises because of reciprocal interactions between the ureteric bud (UB) and the metanephric mesenchyme (MM), driving UB branching and nephron induction. These morphogenetic processes involve a series of cellular rearrangements that are tightly controlled by gene regulatory networks and signaling cascades. Here, we discuss how kidney developmental studies have informed the definition of procedures to obtain kidney organoids from human pluripotent stem cells (hPSCs). Moreover, bioengineering techniques have emerged as potential solutions to externally impose controlled microenvironments for organoid generation from hPSCs. Next, we summarize some of these advances with major focus On recent works merging hPSC-derived kidney organoids (hPSC-kidney organoids) with organ-on-chip to develop robust models for drug discovery and disease modeling applications. We foresee that, in the near future, coupling of different organoid models through bioengineering approaches will help advancing to recreate organ-to-organ crosstalk to increase our understanding on kidney disease progression in the human context and search for new therapeutics.Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.
JTD Keywords: Animal, Animals, Bioengineering, Cell differentiation, Embryo development, Embryology, Embryonic structures, Gene regulatory network, Human, Humans, Kidney, Kidney development, Kidney mesenchyme cell, Kidney organoid, Mammal, Mammals, Mesenchyme, Metanephric mesenchyme, Microenvironment, Nephron, Nephrons, Organoid, Organoids, Physiology, Pluripotent stem cell, Pluripotent stem cells, Review, Signal transduction, Ureteric bud
Kennedy, KE, Abenza, JF, Rossetti, L, Trepat, X, Villoslada, P, Garcia-Ojalvo, J, (2024). Parametric modeling of mechanical effects on circadian oscillators CHAOS 34, 013135
Circadian rhythms are archetypal examples of nonlinear oscillations. While these oscillations are usually attributed to circuits of biochemical interactions among clock genes and proteins, recent experimental studies reveal that they are also affected by the cell's mechanical environment. Here, we extend a standard biochemical model of circadian rhythmicity to include mechanical effects in a parametric manner. Using experimental observations to constrain the model, we suggest specific ways in which the mechanical signal might affect the clock. Additionally, a bifurcation analysis of the system predicts that these mechanical signals need to be within an optimal range for circadian oscillations to occur.
JTD Keywords: Circadian rhythm, Clocks, Coherence, Synchronization
Liu, M, Zhang, C, Gong, XM, Zhang, T, Lian, MM, Chew, EGY, Cardilla, A, Suzuki, K, Wang, HM, Yuan, Y, Li, Y, Naik, MY, Wang, YX, Zhou, BR, Soon, WZ, Aizawa, E, Li, P, Low, JH, Tandiono, M, Montagud, E, Moya-Rull, D, Esteban, CR, Luque, Y, Fang, ML, Khor, CC, Montserrat, N, Campistol, JM, Belmonte, JCI, Foo, JN, Xia, Y, (2024). Kidney organoid models reveal cilium-autophagy metabolic axis as a therapeutic target for PKD both in vitro and in vivo Cell Stem Cell 31, 52-70.e8
Human pluripotent stem cell -derived kidney organoids offer unprecedented opportunities for studying polycystic kidney disease (PKD), which still has no effective cure. Here, we developed both in vitro and in vivo organoid models of PKD that manifested tubular injury and aberrant upregulation of renin-angiotensin aldosterone system. Single -cell analysis revealed that a myriad of metabolic changes occurred during cystogenesis, including defective autophagy. Experimental activation of autophagy via ATG5 overexpression or primary cilia ablation significantly inhibited cystogenesis in PKD kidney organoids. Employing the organoid xenograft model of PKD, which spontaneously developed tubular cysts, we demonstrate that minoxidil, a potent autophagy activator and an FDA -approved drug, effectively attenuated cyst formation in vivo. This in vivo organoid model of PKD will enhance our capability to discover novel disease mechanisms and validate candidate drugs for clinical translation.
JTD Keywords: Adenylate kinase, Adult, Animal cell, Animal experiment, Animal model, Animal tissue, Article, Autophagosome, Autophagy, Autophagy (cellular), Autosomal-dominant, Calcium homeostasis, Cilia, Cilium, Cohort analysis, Controlled study, Cyclic amp, Disease, Dominant polycystic kidney, Enzyme linked immunosorbent assay, Epithelium, Exon, Expression, Female, Food and drug administration, Framework, Generation, Growth, Hepatitis a virus cellular receptor 1, Human, Human cell, Humans, Immunohistochemistry, In vitro study, In vivo study, Kidney, Kidney organoid, Kidney polycystic disease, Male, Minoxidil, Mouse, Mutations, Nonhuman, Organoid, Organoids, Platelet derived growth factor beta receptor, Pluripotent stem-cells, Polycystic kidney diseases, Protein kinase lkb1, Renin, Sequestosome 1, Single cell analysis, Single cell rna seq, Small nuclear rna, Tunel assay, Upregulation, Western blotting, Whole exome sequencing
Jonkman, AH, Warnaar, RSP, Baccinelli, W, Carbon, NM, D'Cruz, RF, Doorduin, J, van Doorn, JLM, Elshof, J, Estrada-Petrocelli, L, Grasshoff, J, Heunks, LMA, Koopman, AA, Langer, D, Moore, CM, Silveira, JMN, Petersen, E, Poddighe, D, Ramsay, M, Rodrigues, A, Roesthuis, LH, Rossel, A, Torres, A, Duiverman, ML, Oppersma, E, (2024). Analysis and applications of respiratory surface EMG: report of a round table meeting CRITICAL CARE 28, 2
Surface electromyography (sEMG) can be used to measure the electrical activity of the respiratory muscles. The possible applications of sEMG span from patients suffering from acute respiratory failure to patients receiving chronic home mechanical ventilation, to evaluate muscle function, titrate ventilatory support and guide treatment. However, sEMG is mainly used as a monitoring tool for research and its use in clinical practice is still limited-in part due to a lack of standardization and transparent reporting. During this round table meeting, recommendations on data acquisition, processing, interpretation, and potential clinical applications of respiratory sEMG were discussed. This paper informs the clinical researcher interested in respiratory muscle monitoring about the current state of the art on sEMG, knowledge gaps and potential future applications for patients with respiratory failure.
JTD Keywords: Acute respiratory failure, Artificial ventilation, Asthmatic-children, Breathing muscle, Clinical monitoring, Clinical practice, Clinical research, Consensus development, Data interpretation, Disease exacerbation, Drive, Electrode positioning, Electrode removal, Electromyography, Force, Home care, Human, Human diaphragm, Humans, Information processing, Inspiratory muscle training, Inspiratory muscles, Intensive care unit, Knowledge gap, Long term care, Mechanical ventilation, Medical procedures, Muscle contraction, Muscle fatigue, Muscle function, Muscle training, Muscle, skeletal, Muscle-activity, Noninvasive ventilation, Patient monitoring, Patient-ventilator asynchrony, Physiology, Prognosis, Quality of life, Reporting and data system, Respiratory failure, Respiratory muscles, Review, Severe exacerbations, Signal processing, Skeletal muscle, Standardization, Surface electromyography, Time factor
Garcia-de-Albeniz, N, Ginebra, MP, Jimenez-Piqué, E, Roa, JJ, Mas-Moruno, C, (2024). Influence of nanosecond laser surface patterning on dental 3Y-TZP: Effects on the topography, hydrothermal degradation and cell response DENTAL MATERIALS 40, 139-150
Laser surface micropatterning of dental-grade zirconia (3Y-TZP) was explored with the objective of providing defined linear patterns capable of guiding bone-cell response.A nanosecond (ns-) laser was employed to fabricate microgrooves on the surface of 3Y-TZP discs, yielding three different groove periodicities (i.e., 30, 50 and 100 µm). The resulting topography and surface damage were characterized by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). X-Ray diffraction (XRD) and Raman spectroscopy techniques were employed to assess the hydrothermal degradation resistance of the modified topographies. Preliminary biological studies were conducted to evaluate adhesion (6 h) of human mesenchymal stem cells (hMSC) to the patterns in terms of cell number and morphology. Finally, Staphylococcus aureus adhesion (4 h) to the microgrooves was investigated.The surface analysis showed grooves of approximately 1.8 µm height that exhibited surface damage in the form of pile-up at the edge of the microgrooves, microcracks and cavities. Accelerated aging tests revealed a slight decrease of the hydrothermal degradation resistance after laser patterning, and the Raman mapping showed the presence of monoclinic phase heterogeneously distributed along the patterned surfaces. An increase of the hMSC area was identified on all the microgrooved surfaces, although only the 50 µm periodicity, which is closer to the cell size, significantly favored cell elongation and alignment along the grooves. A decrease in Staphylococcus aureus adhesion was observed on the investigated micropatterns.The study suggests that linear microgrooves of 50 µm periodicity may help in promoting hMSC adhesion and alignment, while reducing bacterial cell attachment.Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.
JTD Keywords: abutment material, alumina toughened zirconia, antibacterial, bacterial adhesion, biofilm growth, cell adhesion, dental implants, hydrothermal degradation, implant surfaces, in-vitro, laser patterning, osseointegration, osteogenic differentiation, part 1, surface topography, y-tzp ceramics, Antibacterial, Antibacterials, Bacteria, Bone, Cell adhesion, Cell culture, Cells adhesion, Ceramics, Chemistry, Degradation resistance, Dental implants, Dental material, Dental materials, Dental prostheses, Human, Human mesenchymal stem cells, Humans, Hydrothermal degradation, Laser patterning, Laser surface, Lasers, Low-temperature degradation, Materials testing, Microscopy, electron, scanning, Nanosecond lasers, Osseointegration, Piles, Scanning electron microscopy, Staphylococcus aureus, Stem cells, Surface analysis, Surface damages, Surface properties, Surface property, Surface topography, Topography, Yttrium, Zirconia, Zirconium
Diez-Escudero, A, Espanol, M, Ginebra, MP, (2023). High-aspect-ratio nanostructured hydroxyapatite: towards new functionalities for a classical material Chemical Science 15, 55-76
Hydroxyapatite-based materials have been widely used in countless applications, such as bone regeneration, catalysis, air and water purification or protein separation. Recently, much interest has been given to controlling the aspect ratio of hydroxyapatite crystals from bulk samples. The ability to exert control over the aspect ratio may revolutionize the applications of these materials towards new functional materials. Controlling the shape, size and orientation of HA crystals allows obtaining high aspect ratio structures, improving several key properties of HA materials such as molecule adsorption, ion exchange, catalytic reactions, and even overcoming the well-known brittleness of ceramic materials. Regulating the morphogenesis of HA crystals to form elongated oriented fibres has led to flexible inorganic synthetic sponges, aerogels, membranes, papers, among others, with applications in sustainability, energy and catalysis, and especially in the biomedical field.; Hydroxyapatite-based materials have been widely used in countless applications, such as bone regeneration, catalysis, air and water purification or protein separation.
JTD Keywords: Bone, Calcium-phosphate, Doped hydroxyapatite, Fire-resistant, Hydrothermal synthesis, Metal-ions, Nanoparticles, Nanowires, Particle-size, Porous nanocomposite
Piñera-Avellaneda, D, Buxadera-Palomero, J, Ginebra, MP, Rupérez, E, Manero, JM, (2023). Gallium-doped thermochemically treated titanium reduces osteoclastogenesis and improves osteodifferentiation Frontiers in Bioengineering and Biotechnology 11, 1303313
Excessive bone resorption is one of the main causes of bone homeostasis alterations, resulting in an imbalance in the natural remodeling cycle. This imbalance can cause diseases such as osteoporosis, or it can be exacerbated in bone cancer processes. In such cases, there is an increased risk of fractures requiring a prosthesis. In the present study, a titanium implant subjected to gallium (Ga)-doped thermochemical treatment was evaluated as a strategy to reduce bone resorption and improve osteodifferentiation. The suitability of the material to reduce bone resorption was proven by inducing macrophages (RAW 264.7) to differentiate to osteoclasts on Ga-containing surfaces. In addition, the behavior of human mesenchymal stem cells (hMSCs) was studied in terms of cell adhesion, morphology, proliferation, and differentiation. The results proved that the Ga-containing calcium titanate layer is capable of inhibiting osteoclastogenesis, hypothetically by inducing ferroptosis. Furthermore, Ga-containing surfaces promote the differentiation of hMSCs into osteoblasts. Therefore, Ga-containing calcium titanate may be a promising strategy for patients with fractures resulting from an excessive bone resorption disease.Copyright © 2023 Piñera-Avellaneda, Buxadera-Palomero, Ginebra, Rupérez and Manero.
JTD Keywords: biology, bone metastasis, differentiation, ferroptosis, gallium, iron, mouse, osteoclast, osteoporosis, Bone metastasis, Ferroptosis, Gallium, Osteoclast, Osteoporosis, Ti metal, Titanium implant
Boda, SK, Willkomm, N, Barrera, MS, Mansky, L, Aparicio, C, (2023). Electrostatic capture of viruses on cationic biopolymer membranes for intra-oral disease sampling COLLOIDS AND SURFACES B-BIOINTERFACES 232, 113602
Naso- and oropharyngeal swabs are the Center for Disease Control and Prevention (CDC) -recommended disease sampling methods for respiratory viruses. The short swabbing time for sampling by these methods may lead to variability in test results. Further, these methods are mildly invasive and can cause discomfort, tearing or gag reflexes in tested individuals. If longer sampling time is coupled with lesser patient discomfort, test reliability and patient compliance can be improved. Towards this end, we developed cationic biopolymer membranes for the electrostatic capturing of viruses in the oral cavity. Here, chemically (EDC-NHS) crosslinked uncharged chitosan (CS) nanofiber membranes were conferred either with negative surface charge by anionic poly-aspartic acid (pAsp) coating or positive charge by cationic poly-L-lysine (PLL). Consistent with our preliminary findings of dynamic light scattering (DLS) size measurements showing large agglomerates of anionic virus-like particles (VLPs) and cationic PLL in solution, a 75% increase in VLP adsorption by PLL coated CS membranes was recorded by enzyme linked immunosorbent assay (ELISA), in comparison to untreated controls. It is envisaged that the electrostatic concentration of respiratory viruses on cationic membranes can be superior alternatives to traditional swabbing in the oral cavity.
JTD Keywords: Cationic biopolymer membranes, Disease sampling, Dynamic light scattering (dls), Electrostatic capture of viruses, Enzyme linked immunosorbent assay (elisa), Magnetic beads, Virus -like particles (vlps)
Quiñonero, G, Gallo, J, Carrasco, A, Samitier, J, Villasante, A, (2023). Engineering Biomimetic Nanoparticles through Extracellular Vesicle Coating in Cancer Tissue Models Nanomaterials 13, 3097
Using nanoparticles (NPs) in drug delivery has exhibited promising therapeutic potential in various cancer types. Nevertheless, several challenges must be addressed, including the formation of the protein corona, reduced targeting efficiency and specificity, potential immune responses, and issues related to NP penetration and distribution within 3-dimensional tissues. To tackle these challenges, we have successfully integrated iron oxide nanoparticles into neuroblastoma-derived extracellular vesicles (EVs) using the parental labeling method. We first developed a tissue-engineered (TE) neuroblastoma model, confirming the viability and proliferation of neuroblastoma cells for at least 12 days, supporting its utility for EV isolation. Importantly, EVs from long-term cultures exhibited no differences compared to short-term cultures. Concurrently, we designed Rhodamine (Rh) and Polyacrylic acid (PAA)-functionalized magnetite nanoparticles (Fe3O4@PAA-Rh) with high crystallinity, purity, and superparamagnetic properties (average size: 9.2 +/- 2.5 nm). We then investigated the internalization of Fe3O4@PAA-Rh nanoparticles within neuroblastoma cells within the TE model. Maximum accumulation was observed overnight while ensuring robust cell viability. However, nanoparticle internalization was low. Taking advantage of the enhanced glucose metabolism exhibited by cancer cells, glucose (Glc)-functionalized nanoparticles (Fe3O4@PAA-Rh-Glc) were synthesized, showing superior cell uptake within the 3D model without inducing toxicity. These glucose-modified nanoparticles were selected for parental labeling of the TE models, showing effective NP encapsulation into EVs. Our research introduces innovative approaches to advance NP delivery, by partially addressing the challenges associated with 3D systems, optimizing internalization, and enhancing NP stability and specificity through EV-based carriers. Also, our findings hold the promise of more precise and effective cancer therapies while minimizing potential side effects.
JTD Keywords: Biomimetic models, Extracellular vesicles, Iron oxide nanoparticles, Neuroblastoma, Precision medicine
Lanzalaco, S, Sánchez, X, Alemán, C, Weis, C, Traeger, KA, Turon, P, Armelin, E, (2023). Thermo/Pressure-Sensitive Self-Fixation Surgical Meshes: The Role of Adhesive Hydrogels in Interface Attachment ACS Applied Polymer Materials 5, 9898-9908
Herein, an innovative self- and pressure-adhesive biomedical implant was developed. Tissue adhesion was achieved with a thermosensitive hydrogel based on poly-(N-isopropylacrylamide-co-acrylamide), PNIPAAm-co-PAAm, grafted on a substrate composed of knitted fibers of isotactic polypropylene mesh (PP), used as surgical mesh implants. The in vitro studies, carried out with porcine skin, showed an important role of the inclusion of acrylamide-based comonomer (AAm) in the thermosensitive hydrogel PNIPAAm matrix. The bonding, peeling, and shearing energies obtained for PNIPAAm-co-PAAm increased exponentially up to three, two, and six times, respectively, compared to the gel without AAm. The physisorption and mechanical interlocking mechanisms are responsible for such improvement due to the simultaneous creation of hydrophobic and hydrophilic interactions of the thermosensitive hydrogel at temperatures higher than the lower critical solution temperature (LCST), with the porcine tissue. In addition, our bioadhesives present excellent interfacial toughness (similar to 100 J/m(2)) when compared to commercial bioglues (similar to 50 J/m(2) or lower). The results obtained represent a very promising adhesive material that is extensible to other medical devices that require atraumatic fixation to avoid chronic pain related to other fixation approaches.
JTD Keywords: Bioadhesive, Complications, Hernia-repair, Interface adhesion, Mechanicalinterlocking, Physisorption, Poly(n-isopropylacrylamide), Polypropylene mesh, Surgicalmesh, Thermosensitive hydrogel
Barbazan, J, Pérez-González, C, Gómez-González, M, Dedenon, M, Richon, S, Latorre, E, Serra, M, Mariani, P, Descroix, S, Sens, P, Trepat, X, Vignjevic, DM, (2023). Cancer-associated fibroblasts actively compress cancer cells and modulate mechanotransduction Nature Communications 14, 6966
During tumor progression, cancer-associated fibroblasts (CAFs) accumulate in tumors and produce an excessive extracellular matrix (ECM), forming a capsule that enwraps cancer cells. This capsule acts as a barrier that restricts tumor growth leading to the buildup of intratumoral pressure. Combining genetic and physical manipulations in vivo with microfabrication and force measurements in vitro, we found that the CAFs capsule is not a passive barrier but instead actively compresses cancer cells using actomyosin contractility. Abrogation of CAFs contractility in vivo leads to the dissipation of compressive forces and impairment of capsule formation. By mapping CAF force patterns in 3D, we show that compression is a CAF-intrinsic property independent of cancer cell growth. Supracellular coordination of CAFs is achieved through fibronectin cables that serve as scaffolds allowing force transmission. Cancer cells mechanosense CAF compression, resulting in an altered localization of the transcriptional regulator YAP and a decrease in proliferation. Our study unveils that the contractile capsule actively compresses cancer cells, modulates their mechanical signaling, and reorganizes tumor morphology.© 2023. The Author(s).
JTD Keywords: force, migration, yap, Cancer-associated fibroblasts, Cell line, tumor, Fibroblasts, Mechanotransduction, cellular, Neoplasms, Tumor, Tumor microenvironment
Kim, TY, Hong, SH, Jeong, SH, Bae, H, Cheong, S, Choi, H, Hahn, SK, (2023). Multifunctional Intelligent Wearable Devices Using Logical Circuits of Monolithic Gold Nanowires ADVANCED MATERIALS 35, e2303401
Although multifunctional wearable devices have been widely investigated for healthcare systems, augmented/virtual realities, and telemedicines, there are few reports on multiple signal monitoring and logical signal processing by using one single nanomaterial without additional algorithms or rigid application-specific integrated circuit chips. Here, multifunctional intelligent wearable devices are developed using monolithically patterned gold nanowires for both signal monitoring and processing. Gold bulk and hollow nanowires show distinctive electrical properties with high chemical stability and high stretchability. In accordance, the monolithically patterned gold nanowires can be used to fabricate the robust interfaces, programmable sensors, on-demand heating systems, and strain-gated logical circuits. The stretchable sensors show high sensitivity for strain and temperature changes on the skin. Furthermore, the micro-wrinkle structures of gold nanowires exhibit the negative gauge factor, which can be used for strain-gated logical circuits. Taken together, this multifunctional intelligent wearable device would be harnessed as a promising platform for futuristic electronic and biomedical applications.© 2023 Wiley-VCH GmbH.
JTD Keywords: electronics, fabrication, intelligent multifunction, monolithic patterns, signal monitoring and processing, wearable devices, Gold nanowires, Intelligent multifunction, Intraocular-pressure, Monolithic patterns, Signal monitoring and processing, Wearable devices
Hinnekens, C, De Smedt, SC, Fraire, JC, Braeckmans, K, (2023). Non-viral engineering of NK cells BIOTECHNOLOGY ADVANCES 68, 108212
The last decade has witnessed great progress in the field of adoptive cell therapies, with the authorization of Kymriah (tisagenlecleucel) in 2017 by the Food and Drug Administration (FDA) as a crucial stepstone. Since then, five more CAR-T therapies have been approved for the treatment of hematological malignancies. While this is a great step forward to treating several types of blood cancers, CAR-T cell therapies are still associated with severe side-effects such as Graft-versus-Host Disease (GvHD), cytokine release syndrome (CRS) and neurotoxicity. Because of this, there has been continued interest in Natural Killer cells which avoid these side-effects while offering the possibility to generate allogeneic cell therapies. Similar to T-cells, NK cells can be genetically modified to improve their therapeutic efficacy in a variety of ways. In contrast to T cells, viral transduction of NK cells remains inefficient and induces cytotoxic effects. Viral vectors also require a lengthy and expensive product development process and are accompanied by certain risks such as insertional mutagenesis. Therefore, non-viral transfection technologies are avidly being developed aimed at addressing these shortcomings of viral vectors. In this review we will present an overview of the potential of NK cells in cancer immunotherapies and the non-viral transfection technologies that have been explored to engineer them.Copyright © 2023 Elsevier Inc. All rights reserved.
JTD Keywords: adoptive cell therapy, cancer immunotherapy, immunotherapy, messenger-rna delivery, nanoparticle, nk cells, non -viral engineering, sonoporation, t-cell, transfection, ultrasound, Adoptive cell therapy, Cancer immunotherapy, Cell engineering, Natural-killer-cells, Nk cells, Non-viral engineering
Gallo, J, Villasante, A, (2023). Recent Advances in Biomimetic Nanocarrier-Based Photothermal Therapy for Cancer Treatment INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 24, 15484
Nanomedicine presents innovative solutions for cancer treatment, including photothermal therapy (PTT). PTT centers on the design of photoactivatable nanoparticles capable of absorbing non-toxic near-infrared light, generating heat within target cells to induce cell death. The successful transition from benchside to bedside application of PTT critically depends on the core properties of nanoparticles responsible for converting light into heat and the surface properties for precise cell-specific targeting. Precisely targeting the intended cells remains a primary challenge in PTT. In recent years, a groundbreaking approach has emerged to address this challenge by functionalizing nanocarriers and enhancing cell targeting. This strategy involves the creation of biomimetic nanoparticles that combine desired biocompatibility properties with the immune evasion mechanisms of natural materials. This review comprehensively outlines various strategies for designing biomimetic photoactivatable nanocarriers for PTT, with a primary focus on its application in cancer therapy. Additionally, we shed light on the hurdles involved in translating PTT from research to clinical practice, along with an overview of current clinical applications.
JTD Keywords: biomimetic nanoparticles, cancer treatment, diagnosis, drug-delivery, erythrocyte-membrane, facile synthesis, iron-oxide nanoparticles, magnetic nanoparticles, membrane-camouflaged nanoparticles, metastatic breast-cancer, size, stem-cells, Biomimetic nanoparticles, Cancer treatment, Membrane-camouflaged nanoparticles, Photothermal therapy
Mutreja, I, Lan, CX, Li, QS, Aparicio, C, (2023). Chemoselective Coatings of GL13K Antimicrobial Peptides for Dental Implants Pharmaceutics 15, 2418
Dental implant-associated infection is a clinical challenge which poses a significant healthcare and socio-economic burden. To overcome this issue, developing antimicrobial surfaces, including antimicrobial peptide coatings, has gained great attention. Different physical and chemical routes have been used to obtain these biofunctional coatings, which in turn might have a direct influence on their bioactivity and functionality. In this study, we present a silane-based, fast, and efficient chemoselective conjugation of antimicrobial peptides (Cys-GL13K) to coat titanium implant surfaces. Comprehensive surface analysis was performed to confirm the surface functionalization of as-prepared and mechanically challenged coatings. The antibacterial potency of the evaluated surfaces was confirmed against both Streptococcus gordonii and Streptococcus mutans, the primary colonizers and pathogens of dental surfaces, as demonstrated by reduced bacteria viability. Additionally, human dental pulp stem cells demonstrated long-term viability when cultured on Cys-GL13K-grafted titanium surfaces. Cell functionality and antimicrobial capability against multi-species need to be studied further; however, our results confirmed that the proposed chemistry for chemoselective peptide anchoring is a valid alternative to traditional site-unspecific anchoring methods and offers opportunities to modify varying biomaterial surfaces to form potent bioactive coatings with multiple functionalities to prevent infection.
JTD Keywords: biocompatibility, cytotoxicity, delivery, dental implants, prevention, release, stability, surface coating, titanium, zirconia, Antimicrobial peptide, Biocompatibility, Dental implants, Peri-implantitis, Surface coating, Titanium
García-Torres, J, Lázaro, C, Sylla, D, Lanzalaco, S, Ginebra, MP, Alemán, C, (2023). Combining 2D organic and 1D inorganic nanoblocks to develop free-standing hybrid nanomembranes for conformable biosensors Journal of Nanostructure in Chemistry 13, 507-517
We report a simple approach to fabricate free-standing perforated 2D nanomembranes hosting well-ordered 1D metallic nanostructures to obtain hybrid materials with nanostructured surfaces for flexible electronics. Nanomembranes are formed by alternatively depositing perforated poly(lactic acid) (PLA) and poly(3,4-ethylenedioxythiophene) layers. Copper metallic nanowires (NWs) were incorporated into the nanoperforations of the top PLA layer by electrodeposition and further coated with silver via a transmetallation reaction. The combination of 2D polymeric nanomembranes and aligned 1D metallic NWs allows merging the flexibility and conformability of the ultrathin soft polymeric nanomembranes with the good electrical properties of metals for biointegrated electronic devices. Thus, we were able to tailor the nanomembrane surface chemistry as it was corroborated by SEM, EDX, XPS, CV, EIS and contact angle. The obtained hybrid nanomembranes were flexible and conformable showing sensing capacity towards H2O2 with good linear concentration range (0.35–10 mM), sensitivity (120 µA cm?2 mM?1) and limit of detection (7 ?m). Moreover, the membranes showed good stability, reproducibility and selectivity towards H2O2.
JTD Keywords: biointegrated sensors, designs, electronics, fabrication, free-standing films, h2o2, metallic nanowires, nanoparticles, nanowires, sensor, skin, Hydrogen-peroxide, Perforated nanomembranes
Macedo, MH, Torras, N, García-Díaz, M, Barrias, C, Sarmento, B, Martínez, E, (2023). The shape of our gut: Dissecting its impact on drug absorption in a 3D bioprinted intestinal model BIOMATERIALS ADVANCES 153, 213564
The small intestine is a complex organ with a characteristic architecture and a major site for drug and nutrient absorption. The three-dimensional (3D) topography organized in finger-like protrusions called villi increases surface area remarkably, granting a more efficient absorption process. The intestinal mucosa, where this process occurs, is a multilayered and multicell-type tissue barrier. In vitro intestinal models are routinely used to study different physiological and pathological processes in the gut, including compound absorption. Still, standard models are typically two-dimensional (2D) and represent only the epithelial barrier, lacking the cues offered by the 3D architecture and the stromal components present in vivo, often leading to inaccurate results. In this work, we studied the impact of the 3D architecture of the gut on drug transport using a bioprinted 3D model of the intestinal mucosa containing both the epithelial and the stromal compartments. Human intestinal fibroblasts were embedded in a previously optimized hydrogel bioink, and enterocytes and goblet cells were seeded on top to mimic the intestinal mucosa. The embedded fibroblasts thrived inside the hydrogel, remodeling the surrounding extracellular matrix. The epithelial cells fully covered the hydrogel scaffolds and formed a uniform cell layer with barrier properties close to in vivo. In particular, the villus-like model revealed overall increased permeability compared to a flat counterpart composed by the same hydrogel and cells. In addition, the efflux activity of the P-glycoprotein (P-gp) transporter was significantly reduced in the villus-like scaffold compared to a flat model, and the genetic expression of other drugs transporters was, in general, more relevant in the villus-like model. Globally, this study corroborates that the presence of the 3D architecture promotes a more physiological differentiation of the epithelial barrier, providing more accurate data on drug absorbance measurements.Copyright © 2023. Published by Elsevier B.V.
JTD Keywords: 3d architecture, alkaline-phosphatase, caco-2 cells, culture, drug development, efflux proteins, gene-expression, human-colon, intestinal absorption, intestinal models, microenvironment, paracellular transport, permeability, photopolymerization, villi, 3d architecture, 3d bioprinting, Drug development, In-vitro, Intestinal absorption, Intestinal models, Photopolymerization, Villi
Farré, R, Navajas, D, (2023). Ventilation Mechanics SEMINARS IN RESPIRATORY AND CRITICAL CARE MEDICINE 44, 511-525
A fundamental task of the respiratory system is to operate as a mechanical gas pump ensuring that fresh air gets in close contact with the blood circulating through the lung capillaries to achieve O2 and CO2 exchange. To ventilate the lungs, the respiratory muscles provide the pressure required to overcome the viscoelastic mechanical load of the respiratory system. From a mechanical viewpoint, the most relevant respiratory system properties are the resistance of the airways (R aw), and the compliance of the lung tissue (C L) and chest wall (C CW). Both airflow and lung volume changes in spontaneous breathing and mechanical ventilation are determined by applying the fundamental mechanical laws to the relationships between the pressures inside the respiratory system (at the airway opening, alveolar, pleural, and muscular) and R aw, C L, and C CW. These relationships also are the basis of the different methods available to measure respiratory mechanics during spontaneous and artificial ventilation. Whereas a simple mechanical model (R aw, C L, and C CW) describes the basic understanding of ventilation mechanics, more complex concepts (nonlinearity, inhomogeneous ventilation, or viscoelasticity) should be employed to better describe and measure ventilation mechanics in patients.Thieme. All rights reserved.
JTD Keywords: airway-resistance, alveolar, compliance, dilution, elastance, flow, inhomogeneous ventilation, input impedance, lung-volume, mechanical ventilation, monitoring, pendelluft, pleural pressure, respiratory-distress-syndrome, viscoelasticity, Chest-wall mechanics, Resistance
Quiroga, X, Walani, N, Disanza, A, Chavero, A, Mittens, A, Tebar, F, Trepat, X, Parton, RG, Geli, MI, Scita, G, Arroyo, M, Le Roux, AL, Roca-Cusachs, P, (2023). A mechanosensing mechanism controls plasma membrane shape homeostasis at the nanoscale eLife 12, e72316
As cells migrate and experience forces from their surroundings, they constantly undergo mechanical deformations which reshape their plasma membrane (PM). To maintain homeostasis, cells need to detect and restore such changes, not only in terms of overall PM area and tension as previously described, but also in terms of local, nanoscale topography. Here, we describe a novel phenomenon, by which cells sense and restore mechanically induced PM nanoscale deformations. We show that cell stretch and subsequent compression reshape the PM in a way that generates local membrane evaginations in the 100 nm scale. These evaginations are recognized by I-BAR proteins, which triggers a burst of actin polymerization mediated by Rac1 and Arp2/3. The actin polymerization burst subsequently re-flattens the evagination, completing the mechanochemical feedback loop. Our results demonstrate a new mechanosensing mechanism for PM shape homeostasis, with potential applicability in different physiological scenarios.© 2023, Quiroga et al.
JTD Keywords: arp2/3 complex, bar, bar proteins, cdc42, cells, domain, human, irsp53, membrane biophysics, mouse, proteins, rac, tension, Actin polymerization, Actins, Bar proteins, Cell biology, Cell membrane, Homeostasis, Human, Mechanobiology, Membrane biophysics, Mouse, Physics of living systems
Sauer, F, Grosser, S, Shahryari, M, Hayn, A, Guo, J, Braun, J, Briest, S, Wolf, B, Aktas, B, Horn, LC, Sack, I, Käs, JA, (2023). Changes in Tissue Fluidity Predict Tumor Aggressiveness In Vivo Advanced Science 10, e2303523
Cancer progression is caused by genetic changes and associated with various alterations in cell properties, which also affect a tumor's mechanical state. While an increased stiffness has been well known for long for solid tumors, it has limited prognostic power. It is hypothesized that cancer progression is accompanied by tissue fluidization, where portions of the tissue can change position across different length scales. Supported by tabletop magnetic resonance elastography (MRE) on stroma mimicking collagen gels and microscopic analysis of live cells inside patient derived tumor explants, an overview is provided of how cancer associated mechanisms, including cellular unjamming, proliferation, microenvironment composition, and remodeling can alter a tissue's fluidity and stiffness. In vivo, state-of-the-art multifrequency MRE can distinguish tumors from their surrounding host tissue by their rheological fingerprints. Most importantly, a meta-analysis on the currently available clinical studies is conducted and universal trends are identified. The results and conclusions are condensed into a gedankenexperiment about how a tumor can grow and eventually metastasize into its environment from a physics perspective to deduce corresponding mechanical properties. Based on stiffness, fluidity, spatial heterogeneity, and texture of the tumor front a roadmap for a prognosis of a tumor's aggressiveness and metastatic potential is presented.© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.
JTD Keywords: brain, cancer, cells, collective migration, elastic energy, elastography, in vivo magnetic resonance elastography, invasion, medical imaging, solid stress, tissue fluidity, tumor mechanics, viscoelastic properties, Cancer, Collagen, Extracellular-matrix, Humans, In vivo magnetic resonance elastography, Medical imaging, Neoplasms, Prognosis, Tissue fluidity, Tumor mechanics, Tumor microenvironment
Gregori-Pla, C, Zirak, P, Cotta, G, Bramon, P, Blanco, I, Serra, I, Mola, A, Fortuna, A, Solà-Soler, J, Giraldo, BFG, Durduran, T, Mayos, M, (2023). How does obstructive sleep apnea alter cerebral hemodynamics? SLEEP 46, zsad122
We aimed to characterize the cerebral hemodynamic response to obstructive sleep apnea/hypopnea events, and evaluate their association to polysomnographic parameters. The characterization of the cerebral hemodynamics in obstructive sleep apnea (OSA) may add complementary information to further the understanding of the severity of the syndrome beyond the conventional polysomnography.Severe OSA patients were studied during night sleep while monitored by polysomnography. Transcranial, bed-side diffuse correlation spectroscopy (DCS) and frequency-domain near-infrared diffuse correlation spectroscopy (NIRS-DOS) were used to follow microvascular cerebral hemodynamics in the frontal lobes of the cerebral cortex. Changes in cerebral blood flow (CBF), total hemoglobin concentration (THC), and cerebral blood oxygen saturation (StO2) were analyzed.We considered 3283 obstructive apnea/hypopnea events from sixteen OSA patients (Age (median, interquartile range) 57 (52-64.5); females 25%; AHI (apnea-hypopnea index) 84.4 (76.1-93.7)). A biphasic response (maximum/minimum followed by a minimum/maximum) was observed for each cerebral hemodynamic variable (CBF, THC, StO2), heart rate and peripheral arterial oxygen saturation (SpO2). Changes of the StO2 followed the dynamics of the SpO2, and were out of phase from the THC and CBF. Longer events were associated with larger CBF changes, faster responses and slower recoveries. Moreover, the extrema of the response to obstructive hypopneas were lower compared to apneas (p < .001).Obstructive apneas/hypopneas cause profound, periodic changes in cerebral hemodynamics, including periods of hyper- and hypo-perfusion and intermittent cerebral hypoxia. The duration of the events is a strong determinant of the cerebral hemodynamic response, which is more pronounced in apnea than hypopnea events.© The Author(s) 2023. Published by Oxford University Press on behalf of Sleep Research Society.
JTD Keywords: cerebral hemodynamics, desaturation, diffuse correlation spectroscopy, duration, hypopnea, hypoxemia, near-infrared spectroscopy, optical pathlength, oxygenation, severity, sleep disorder, spectroscopy, tissue, Adult, Airway obstruction, Apnea hypopnea index, Arterial oxygen saturation, Article, Blood oxygen tension, Blood-flow, Brain blood flow, Brain cortex, Cerebral hemodynamics, Controlled study, Diffuse correlation spectroscopy, Disease severity, Female, Frequency, Frontal lobe, Heart rate, Hemodynamics, Hemoglobin, Hemoglobin determination, Human, Humans, Major clinical study, Male, Near infrared spectroscopy, Near-infrared spectroscopy, Obstructive sleep apnea, Oxygen, Periodicity, Polysomnography, Sleep apnea syndromes, Sleep apnea, obstructive, Sleep disorder, Spectroscopy, near-infrared
Rodriguez, J, Schulz, S, Voss, A, Herrera, S, Benito, S, Giraldo, BF, (2023). Baroreflex activity through the analysis of the cardio-respiratory variability influence over blood pressure in cardiomyopathy patients Frontiers in Physiology 14, 1184293
A large portion of the elderly population are affected by cardiovascular diseases. Early prognosis of cardiomyopathies remains a challenge. The aim of this study was to classify cardiomyopathy patients by their etiology based on significant indexes extracted from the characterization of the baroreflex mechanism in function of the influence of the cardio-respiratory activity over the blood pressure. Forty-one cardiomyopathy patients (CMP) classified as ischemic (ICM-24 patients) and dilated (DCM-17 patients) were considered. In addition, thirty-nine control (CON) subjects were used as reference. The beat-to-beat (BBI) time series, from the electrocardiographic (ECG) signal, the systolic (SBP), and diastolic (DBP) time series, from the blood pressure signal (BP), and the respiratory time (TT), from the respiratory flow (RF) signal, were extracted. The three-dimensional representation of the cardiorespiratory and vascular activities was characterized geometrically, by fitting a polygon that contains 95% of data, and by statistical descriptive indices. DCM patients presented specific patterns in the respiratory response to decreasing blood pressure activity. ICM patients presented more stable cardiorespiratory activity in comparison with DCM patients. In general, CMP shown limited ability to regulate changes in blood pressure. In addition, patients also shown a limited ability of their cardiac and respiratory systems response to regulate incremental changes of the vascular variability and a lower heart rate variability. The best classifiers were used to build support vector machine models. The optimal model to classify ICM versus DCM patients achieved 92.7% accuracy, 94.1% sensitivity, and 91.7% specificity. When comparing CMP patients and CON subjects, the best model achieved 86.2% accuracy, 82.9% sensitivity, and 89.7% specificity. When comparing ICM patients and CON subjects, the best model achieved 88.9% accuracy, 87.5% sensitivity, and 89.7% specificity. When comparing DCM patients and CON subjects, the best model achieved 87.5% accuracy, 76.5% sensitivity, and 92.3% specificity. In conclusion, this study introduced a new method for the classification of patients by their etiology based on new indices from the analysis of the baroreflex mechanism.Copyright © 2023 Rodriguez, Schulz, Voss, Herrera, Benito and Giraldo.
JTD Keywords: abnormalities, blood pressure variability, cardio-respiratory variability, dilated cardiomyopathy, disease, heart-failure secondary, ischemic cardiomyopathy, ischemic-dilated cardiomyopathy, morphology-relative change, Baroreflex activity, Blood pressure variability, Cardio-respiratory variability, Cheyne-stokes respiration, Ischemic-dilated cardiomyopathy, Morphology-relative change
Rodríguez-Comas, J, Castaño, C, Ortega, MA, Tejedera, A, Fernandez-González, M, Novials, A, Párrizas, M, Ramón-Azcón, J, (2023). Immunoaffinity‐Based Microfluidic Platform for Exosomal MicroRNA Isolation from Obese and Lean Mouse Plasma Advanced Materials Technologies 8, 2300054
Liu, TY, De Pace, C, Huang, RD, Bruno, G, Shao, T, Tian, YP, Chen, B, Chen, L, Luo, K, Gong, QY, Ruiz-Pérez, L, Battaglia, G, Tian, XH, (2023). An Iridium (III) complex revealing cytoskeleton nanostructures under super-resolution nanoscopy and liquid-phase electron microscopy SENSORS AND ACTUATORS B-CHEMICAL 388, 133839
Live cell actin visualization is fundamental for exploring cellular motility, cytokinesis, intracellular transport, and other correlated functions. The current imaging techniques that allow imaging of actin in its native environment are optical and electron microscopy. Such imaging techniques offer high enough resolution to investigate the ultrastructure of actin however they come at the expense of actin integrity. Inspired by the lack of suitable probes that preserve actin's integrity, we designed a cyclometalated Ir (III) complex that interacts with live cells and displays light switch behaviour upon specific actin binding. The exceptional photophysical properties of the proposed probe allow unprecedented resolution of cytoskeleton ultrastructures under stimulated emission depletion (STED) super-resolution nanoscopy. Moreover, the Ir complex enables the capability of visualizing actin polymers and periodicity under correlative light electron microscopy (CLEM) and liquid-phase electron microscopy (LPEM) at similar to 8 nm resolution.
JTD Keywords: Actin dynamics, Actin targeting, Adhesion, Cells, Clem, Fluorescent, Iridium (iii) complex, Lead, Light, Lpem, Super-resolution ultrastructures
Chuchkova, L, Bodenstedt, S, Picazo-Frutos, R, Eills, J, Tretiak, O, Hu, YA, Barskiy, DA, de Santis, J, Tayler, MCD, Budker, D, Sheberstov, KF, (2023). Magnetometer-Detected Nuclear Magnetic Resonance of Photochemically Hyperpolarized Molecules Journal of Physical Chemistry Letters 14, 6814-6822
Photochemically induced dynamic nuclear polarization (photo-CIDNP) enables nuclear spin ordering by irradiating samples with light. Polarized spins are conventionally detected via high-field chemical-shift-resolved NMR (above 0.1 T). In this Letter, we demonstrate in situ low-field photo-CIDNP measurements using a magnetically shielded fast-field-cycling NMR setup detecting Larmor precession via atomic magnetometers. For solutions comprising mM concentrations of the photochemically polarized molecules, hyperpolarized 1H magnetization is detected by pulse-acquired NMR spectroscopy. The observed NMR line widths are about 5 times narrower than normally anticipated in high-field NMR and are systematically affected by light irradiation during the acquisition period, reflecting a reduction of the transverse relaxation time constant, T2*, on the order of 10%. Magnetometer-detected photo-CIDNP spectroscopy enables straightforward observation of spin-chemistry processes in the ambient field range from a few nT to tens of mT. Potential applications of this measuring modality are discussed.
JTD Keywords: field-dependence, mechanism, nmr, parahydrogen, photo-cidnp, polarization, quinone, spin-hyperpolarization, Radical-pair
Colom-Cadena, M, Davies, C, Sirisi, S, Lee, JE, Simzer, EM, Tzioras, M, Querol-Vilaseca, M, Sánchez-Aced, E, Chang, YY, Holt, K, McGeachan, RI, Rose, J, Tulloch, J, Wilkins, L, Smith, C, Andrian, T, Belbin, O, Pujals, S, Horrocks, MH, Lleó, A, Spires-Jones, TL, (2023). Synaptic oligomeric tau in Alzheimer's disease - A potential culprit in the spread of tau pathology through the brain NEURON 111, 2170-+
In Alzheimer's disease, fibrillar tau pathology accumulates and spreads through the brain and synapses are lost. Evidence from mouse models indicates that tau spreads trans-synaptically from pre- to postsynapses and that oligomeric tau is synaptotoxic, but data on synaptic tau in human brain are scarce. Here we used sub-diffraction-limit microscopy to study synaptic tau accumulation in postmortem temporal and occipital cortices of human Alzheimer's and control donors. Oligomeric tau is present in pre- and postsynaptic terminals, even in areas without abundant fibrillar tau deposition. Furthermore, there is a higher proportion of oligomeric tau compared with phosphorylated or misfolded tau found at synaptic terminals. These data suggest that accumulation of oligomeric tau in synapses is an early event in pathogenesis and that tau pathology may progress through the brain via trans-synaptic spread in human disease. Thus, specifically reducing oligomeric tau at synapses may be a promising therapeutic strategy for Alzheimer's disease.Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.
JTD Keywords: accumulation, alpha-synuclein, array tomography, cognitive impairment, dendritic spines, mouse model, neurodegeneration, neurons, synapses, Alzheimer, Amyloid-beta, Synapse, Tau
Almici, E, Arshakyan, M, Carrasco, JL, Martinez, A, Ramirez, J, Enguita, AB, Monso, E, Montero, J, Samitier, J, Alcaraz, J, (2023). Quantitative Image Analysis of Fibrillar Collagens Reveals Novel Diagnostic and Prognostic Biomarkers and Histotype-Dependent Aberrant Mechanobiology in Lung Cancer MODERN PATHOLOGY 36, 100155
Fibrillar collagens are the most abundant extracellular matrix components in non-small cell lung cancer (NSCLC). However, the potential of collagen fiber descriptors as a source of clinically relevant biomarkers in NSCLC is largely unknown. Similarly, our understanding of the aberrant collagen organization and associated tumor-promoting effects is very scarce. To address these limitations, we identified a digital pathology approach that can be easily implemented in pa-thology units based on CT-FIRE software (version 2; https://loci.wisc.edu/software/ctfire) analysis of Picrosirius red (PSR) stains of fibrillar collagens imaged with polarized light (PL). CT-FIRE set-tings were pre-optimized to assess a panel of collagen fiber descriptors in PSR-PL images of tissue microarrays from surgical NSCLC patients (106 adenocarcinomas [ADC] and 89 squamous cell carcinomas [SCC]). Using this approach, we identified straightness as the single high-accuracy diagnostic collagen fiber descriptor (average area under the curve 1/4 0.92) and fiber density as the single descriptor consistently associated with a poor prognosis in both ADC and SCC inde-pendently of the gold standard based on the TNM staging (hazard ratio, 2.69; 95% CI, 1.55-4.66; P < .001). Moreover, we found that collagen fibers were markedly straighter, longer, and more aligned in tumor samples compared to paired samples from uninvolved pulmonary tissue, particularly in ADC, which is indicative of increased tumor stiffening. Consistently, we observed an increase in a panel of stiffness-associated processes in the high collagen fiber density patient group selectively in ADC, including venous/lymphatic invasion, fibroblast activation (a-smooth muscle actin), and immune evasion (programmed death-ligand 1). Similarly, a transcriptional correlation analysis supported the potential involvement of the major YAP/TAZ pathway in ADC. Our results provide a proof-of-principle to use CT-FIRE analysis of PSR-PL images to assess new collagen fiber-based diagnostic and prognostic biomarkers in pathology units, which may improve the clinical management of patients with surgical NSCLC. Our findings also unveil an aberrant stiff micro -environment in lung ADC that may foster immune evasion and dissemination, encouraging future work to identify therapeutic opportunities. (c) 2023 THE AUTHORS. Published by Elsevier Inc. on behalf of the United States & Canadian Academy of Pathology. This is an open access article under the CC BY-NC-ND license (http://creativecommo ns.org/licenses/by-nc-nd/4.0/).
JTD Keywords: biomarkers, collagen, ct-fire, lung cancer, mechanobiology, Adenocarcinoma, Association, Biomarkers, Collagen, Ct-fire, Differentiation, Expression, Extracellular-matrix, I collagen, Invasion, Lung cancer, Mechanobiology, Microenvironment, Signature, Survival, Tumor microenvironment
Miñana, AF, De Chiara, F, Azcón, JR, (2023). Human three-dimensional multicellular liver platform for drug screening Tissue Engineering Part A 29, OP‐311
Cler, M, Amodio, SP, Martínez, E, Engel, E, Terracciano, CM, (2023). Exogenous lactate improves cardiac function of living myocardial slices Tissue Engineering Part A 29, OP-062
Fernandez, BB, Vinolas, SR, Bagci, G, Amodio, SP, Concheiro, A, Lorenzo, CA, Engel, E, (2023). A 3D in vitro model of breast cancer model using decellularized mammary glands bioinks Tissue Engineering Part A 29, PP-387
Mingot, J, Benejam, N, Víllora, G, Alemán, C, Armelin, E, Lanzalaco, S, (2023). Multimodal Biomedical Implant with Plasmonic and Simulated Body Temperature Responses MACROMOLECULAR BIOSCIENCE 23, e2300118
This work presents a novel nanoparticle-based thermosensor implant able to reveal the precise temperature variations along the polymer filaments, as it contracts and expands due to changes in the macroscale local temperature. The multimodal device is able to trace the position and the temperature of a polypropylene mesh, employed in abdominal hernia repair, by combining plasmon resonance and Raman spectroscopy with hydrogel responsive system. The novelty relies on the attachment of the biocompatible nanoparticles, based on gold stabilized by a chitosan-shell, already charged with the Raman reporter (RaR) molecules, to the robust prosthesis, without the need of chemical linkers. The SERS enhanced effect observed is potentiated by the presence of a quite thick layer of the copolymer (poly(N-isopropylacrylamide)-co-poly(acrylamide)) hydrogel. At temperatures above the LCST of PNIPAAm-co-PAAm, the water molecules are expulsed and the hydrogel layer contracts, leaving the RaR molecules more accessible to the Raman source. In vitro studies with fibroblast cells reveal that the functionalized surgical mesh is biocompatible and no toxic substances are leached in the medium. The mesh sensor opens new frontiers to semi-invasive diagnosis and infection prevention in hernia repair by using SERS spectroscopy. It also offers new possibilities to the functionalization of other healthcare products.© 2023 Wiley-VCH GmbH.
JTD Keywords: adhesion, blends, chitosan, gold nanoparticles, poly(n-isopropylacrylamide), polypropylene mesh, polypropylene meshes, repair, scattering, silver, surgical implants, thermosensitive hydrogels, toxicity, Chitosan, Gold nanoparticles, Polypropylene meshes, Surgical implants, Thermosensitive hydrogels
Schierwagen, R, Gu, WY, Brieger, A, Brüne, B, Ciesek, S, Dikic, I, Dimmeler, S, Geisslinger, G, Greten, FR, Hermann, E, Hildt, E, Kempf, VAJ, Klein, S, Koch, I, Mühl, H, Müller, V, Peiffer, KH, Kestner, RI, Piiper, A, Rohde, G, Scholich, K, Schulz, MH, Storf, H, Toptan, T, Vasa-Nicotera, M, Vehreschild, MJGT, Weigert, A, Wild, PJ, Zeuzem, S, Engelmann, C, Schaefer, L, Welsch, C, Trebicka, J, (2023). Pathogenetic mechanisms and therapeutic approaches of acute-to-chronic liver failure AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY 325, C129-C140
Liver cirrhosis is the end stage of all chronic liver diseases and contributes significantly to overall mortality of 2% globally. The age-standardized mortality from liver cirrhosis in Europe is between 10 and 20% and can be explained by not only the development of liver cancer but also the acute deterioration in the patient's overall condition. The development of complications including accumulation of fluid in the abdomen (ascites), bleeding in the gastrointestinal tract (variceal bleeding), bacterial infections, or a decrease in brain function (hepatic encephalopathy) define an acute decompensation that requires therapy and often leads to acute-on-chronic liver failure (ACLF) by different precipitating events. However, due to its complexity and organ-spanning nature, the pathogenesis of ACLF is poorly understood, and the common underlying mechanisms leading to the development of organ dysfunction or failure in ACLF are still elusive. Apart from general intensive care interventions, there are no specific therapy options for ACLF. Liver transplantation is often not possible in these patients due to contraindications and a lack of prioritization. In this review, we describe the framework of the ACLF-I project consortium funded by the Hessian Ministry of Higher Education, Research and the Arts (HMWK) based on existing findings and will provide answers to these open questions.
JTD Keywords: 12/15-lipoxygenase, combination, inflammation, interleukin-22, metabolism, mortality, organ failure, portal-hypertension, receptor, regeneration, systemic inflammation, systems medicine, translational hepatology, Decompensated cirrhosis, Organ failure, Systemic inflammation, Systems medicine, Translational hepatology
Abenza, JF, Rossetti, L, Mouelhi, M, Burgués, J, Andreu, I, Kennedy, K, Roca-Cusachs, P, Marco, S, García-Ojalvo, J, Trepat, X, (2023). Mechanical control of the mammalian circadian clock via YAP/TAZ and TEAD JOURNAL OF CELL BIOLOGY 222, e202209120
Autonomous circadian clocks exist in nearly every mammalian cell type. These cellular clocks are subjected to a multilayered regulation sensitive to the mechanochemical cell microenvironment. Whereas the biochemical signaling that controls the cellular circadian clock is increasingly well understood, mechanisms underlying regulation by mechanical cues are largely unknown. Here we show that the fibroblast circadian clock is mechanically regulated through YAP/TAZ nuclear levels. We use high-throughput analysis of single-cell circadian rhythms and apply controlled mechanical, biochemical, and genetic perturbations to study the expression of the clock gene Rev-erbα. We observe that Rev-erbα circadian oscillations are disrupted with YAP/TAZ nuclear translocation. By targeted mutations and overexpression of YAP/TAZ, we show that this mechanobiological regulation, which also impacts core components of the clock such as Bmal1 and Cry1, depends on the binding of YAP/TAZ to the transcriptional effector TEAD. This mechanism could explain the impairment of circadian rhythms observed when YAP/TAZ activity is upregulated, as in cancer and aging.© 2023 Abenza et al.
JTD Keywords: activation, dynamics, forces, growth, hippo pathway, liver, platform, time, transcription, Animals, Circadian clocks, Circadian rhythm, Gene-expression, Mammals, Signal transduction, Tea domain transcription factors, Transcriptional coactivator with pdz-binding motif proteins, Yap-signaling proteins
Javier-Reyna, R, Avalos-Padilla, Y, Marion, S, (2023). Editorial: Vesicular transport, the actin cytoskeleton and their involvement in virulence mechanisms during host-parasite interaction Frontiers in Cellular and Infection Microbiology 13, 1229067
Lanzalaco, S, Weis, C, Traeger, KA, Turon, P, Alemán, C, Armelin, E, (2023). Mechanical Properties of Smart Polypropylene Meshes: Effects of Mesh Architecture, Plasma Treatment, Thermosensitive Coating, and Sterilization Process ACS Biomaterials Science & Engineering 9, 3699-3711
Smart polypropylene (PP) hernia meshes were proposed to detect surgical infections and to regulate cell attachment-modulated properties. For this purpose, lightweight and midweight meshes were modified by applying a plasma treatment for subsequent grafting of a thermosensitive hydrogel, poly(N-isopropylacrylamide) (PNIPAAm). However, both the physical treatment with plasma and the chemical processes required for the covalent incorporation of PNIPAAm can modify the mechanical properties of the mesh and thus have an influence in hernia repair procedures. In this work, the mechanical performance of plasma-treated and hydrogel-grafted meshes preheated at 37 °C has been compared with standard meshes using bursting and the suture pull out tests. Furthermore, the influence of the mesh architecture, the amount of grafted hydrogel, and the sterilization process on such properties have been examined. Results reveal that although the plasma treatment reduces the bursting and suture pull out forces, the thermosensitive hydrogel improves the mechanical resistance of the meshes. Moreover, the mechanical performance of the meshes coated with the PNIPAAm hydrogel is not influenced by ethylene oxide gas sterilization. Micrographs of the broken meshes evidence the role of the hydrogel as reinforcing coating for the PP filaments. Overall, results confirm that the modification of PP medical textiles with a biocompatible thermosensitive hydrogel do not affect, and even improve, the mechanical requirements necessary for the implantation of these prostheses in vivo.
JTD Keywords: biomaterials, bursting test, etox sterilization, hernia repair, hydrogels, infection, poly(n-isopropylacrylamide), pull outtest, surgical mesh, Abdominal-wall, Biomedical implant, Bursting test, Etox sterilization, Poly(n-isopropylacrylamide), Pull out test, Surgical mesh
Chausse, V, Casanova-Batlle, E, Canal, C, Ginebra, MP, Ciurana, J, Pegueroles, M, (2023). Solvent-cast direct-writing and electrospinning as a dual fabrication strategy for drug-eluting polymeric bioresorbable stents Additive Manufacturing 71, 103568
JTD Keywords: alignment, bioresorbable stents, cells, design, electrospinning, everolimus, impact, in-vitro, poly(l-lactic-co-e-caprolactone), proliferation, release, sirolimus, Scaffold topography, Solvent-cast direct-writing
Macor, LP, Colombi, S, Tamarit, JL, Engel, E, Pérez-Madrigal, MM, García-Torres, J, Alemán, C, (2023). Immediate-sustained lactate release using alginate hydrogel assembled to proteinase K/polymer electrospun fibers INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 238, 124117
This work proposes a microfibers-hydrogel assembled composite as delivery vehicle able to combine into a single system both burst and prolonged release of lactate. The prolonged release of lactate has been achieved by electrospinning a mixture of polylactic acid and proteinase K (26.0 mg of proteinase K and 0.99 g of PLA dissolved in 6 mL of 2:1 chloroform:acetone in the optimal case), which is a protease that catalyzes the degradation of polylactic acid into lactate. The degradation of microfibers into lactate reflects that proteinase K preserves its enzymatic activity even after the electrospinning process because of the mild operational conditions used. Besides, burst release is obtained from the lactate-loaded alginate hydrogel. The successful assembly between the lactate-loaded hydrogel and the polylactic acid/proteinase K fibers has been favored by applying a low-pressure (0.3 mbar at 300 W) oxygen plasma treatment, which transforms hydrophobic fibers into hydrophilic while the enzymatic activity is still maintained. The composite displays both fast (< 24 h) and sustained (> 10 days) lactate release, and allows the modulation of the release by adjusting either the amount of loaded lactate or the amount of active enzyme.Copyright © 2023. Published by Elsevier B.V.
JTD Keywords: biodegradable fibers, proteases, regeneration, repair, Alginate, Alginates, Biodegradable fibers, Endopeptidase k, Hydrogels, Lactic acid, Myocardial-infarction, Polymers, Proteases
Oerther, C, Marco-Rius, I, (2023). Chapter 14: Fast Multi-dimensional NMR for In Vivo Spectroscopy New Developments in NMR 27, 415-440
González-Callejo, P, Gener, P, Díaz-Riascos, Z, Conti, S, Cámara-Sánchez, P, Riera, R, Mancilla, S, García-Gabilondo, M, Peg, V, Arango, D, Rosell, A, Labernadie, A, Trepat, X, Albertazzi, L, Schwartz, S Jr, Seras-Franzoso, J, Abasolo, I, (2023). Extracellular vesicles secreted by triple-negative breast cancer stem cells trigger premetastatic niche remodeling and metastatic growth in the lungs INTERNATIONAL JOURNAL OF CANCER 152, 2153-2165
Tumor secreted extracellular vesicles (EVs) are potent intercellular signaling platforms. They are responsible for the accommodation of the premetastatic niche (PMN) to support cancer cell engraftment and metastatic growth. However, complex cancer cell composition within the tumor increases also the heterogeneity among cancer secreted EVs subsets, a functional diversity that has been poorly explored. This phenomenon is particularly relevant in highly plastic and heterogenous triple-negative breast cancer (TNBC), in which a significant representation of malignant cancer stem cells (CSCs) is displayed. Herein, we selectively isolated and characterized EVs from CSC or differentiated cancer cells (DCC; EVsCSC and EVsDCC , respectively) from the MDA-MB-231 TNBC cell line. Our results showed that EVsCSC and EVsDCC contain distinct bioactive cargos and therefore elicit a differential effect on stromal cells in the TME. Specifically, EVsDCC activated secretory cancer associated fibroblasts (CAFs), triggering IL-6/IL-8 signaling and sustaining CSC phenotype maintenance. Complementarily, EVsCSC promoted the activation of α-SMA+ myofibroblastic CAFs subpopulations and increased the endothelial remodeling, enhancing the invasive potential of TNBC cells in vitro and in vivo. In addition, solely the EVsCSC mediated signaling prompted the transformation of healthy lungs into receptive niches able to support metastatic growth of breast cancer cells.© 2023 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.
JTD Keywords: chemoresistance, dormancy, drives, extracellular vesicles, invasion, plasticity, premetastatic niche, triple-negative breast cancer, tumor microenvironment, Cancer cell plasticity, Cell line, tumor, Extracellular vesicles, Fibroblasts, Humans, Lung, Neoplastic stem cells, Premetastatic niche, Triple negative breast neoplasms, Triple-negative breast cancer, Tumor microenvironment
Hernández, F, Ferrer, I, Pérez, M, Zabala, JC, del Rio, JA, Avila, J, (2023). Tau Aggregation NEUROSCIENCE 518, 64-69
Here we revisit tau protein aggregation at primary, secondary, tertiary and quaternary structures. In addition, the presence of non-aggregated tau protein, which has been recently discovered, is also commented on.Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.
JTD Keywords: alpha-helix, alzheimer-disease, antigenic determinants, binding, isomerase pin1, microtubule-binding repeats, neurofibrillary tangles, paired helical filaments, repeat domain, structural-characterization, tau conformations, w-tau isoform, Microtubule-associated protein, Microtubule-binding repeats, Tau, Tau conformations, W-tau isoform
Overby, SJ, Cerro-Herreros, E, Espinosa-Espinosa, J, González-Martínez, I, Moreno, N, Fernández-Costa, JM, Balaguer-Trias, J, Ramón-Azcón, J, Pérez-Alonso, M, Moller, T, Llamusí, B, Artero, R, (2023). BlockmiR AONs as Site-Specific Therapeutic MBNL Modulation in Myotonic Dystrophy 2D and 3D Muscle Cells and HSALR Mice Pharmaceutics 15, 1118
The symptoms of Myotonic Dystrophy Type 1 (DM1) are multi-systemic and life-threatening. The neuromuscular disorder is rooted in a non-coding CTG microsatellite expansion in the DM1 protein kinase (DMPK) gene that, upon transcription, physically sequesters the Muscleblind-like (MBNL) family of splicing regulator proteins. The high-affinity binding occurring between the proteins and the repetitions disallow MBNL proteins from performing their post-transcriptional splicing regulation leading to downstream molecular effects directly related to disease symptoms such as myotonia and muscle weakness. In this study, we build on previously demonstrated evidence showing that the silencing of miRNA-23b and miRNA-218 can increase MBNL1 protein in DM1 cells and mice. Here, we use blockmiR antisense technology in DM1 muscle cells, 3D mouse-derived muscle tissue, and in vivo mice to block the binding sites of these microRNAs in order to increase MBNL translation into protein without binding to microRNAs. The blockmiRs show therapeutic effects with the rescue of mis-splicing, MBNL subcellular localization, and highly specific transcriptomic expression. The blockmiRs are well tolerated in 3D mouse skeletal tissue inducing no immune response. In vivo, a candidate blockmiR also increases Mbnl1/2 protein and rescues grip strength, splicing, and histological phenotypes.
JTD Keywords: antisense oligonucleotides, aon, blockmir, brain, expression, genes, mbnl, mir-218, mir-23b, mirna, muscleblind, myotonic dystrophy 1, phenotypes, proteins, type-1, Antisense oligonucleotides, Aon, Blockmir, Mbnl, Messenger-rna, Mir-218, Mir-23b, Mirna, Muscleblind, Myotonic dystrophy 1
Romero, D, Jané, R, (2023). Dynamic Bayesian Model for Detecting Obstructive Respiratory Events by Using an Experimental Model SENSORS 23, 3371-3371
In this study, we propose a model-based tool for the detection of obstructive apnea episodes by using ECG features from a single lead channel. Several sequences of recurrent apnea were provoked in separate 15-min periods in anesthetized rats during an experimental model of obstructive sleep apnea (OSA). Morphology-based ECG markers and the beat-to-beat interval (RR) were assessed in each sequence. These markers were used to train dynamic Bayesian networks (DBN) with different orders and feature combinations to find a good tradeoff between network complexity and apnea-detection performance. By using a filtering approach, the resulting DBNs were used to infer the apnea probability signal for subsequent episodes in the same rat. These signals were then processed using by 15-s epochs to determine whether epochs were classified as apneic or nonapneic. Our results showed that fifth-order models provided suitable RMSE values, since higher order models become significantly more complex and present worse generalization. A global threshold of 0.2 gave the best overall performance for all combinations tested, with Acc = 81.3%, Se = 69.8% and Sp = 81.5%, using only two parameters including the RR and Ds (R-wave downslope) markers. We concluded that multivariate models using DBNs represent a powerful tool for detecting obstructive apnea episodes in short segments, which may also serve to estimate the number of total events in a given time period.
JTD Keywords: chronic respiratory diseases, obstructive sleep apnea, probabilistic models, Obstructive sleep apnea,probabilistic models,respiratory events,chronic respiratory disease, Respiratory events, Sleep-apnea syndrome,automated detection,oxygen-saturation,classification,recordings,signal
Fontcuberta-PiSunyer, M, García-Alamán, A, Prades, É, Téllez, N, Alves-Figueiredo, H, Ramos-Rodríguez, M, Enrich, C, Fernandez-Ruiz, R, Cervantes, S, Clua, L, Ramón-Azcón, J, Broca, C, Wojtusciszyn, A, Montserrat, N, Pasquali, L, Novials, A, Servitja, JM, Vidal, J, Gomis, R, Gasa, R, (2023). Direct reprogramming of human fibroblasts into insulin-producing cells using transcription factors Communications Biology 6, 256
Direct lineage reprogramming of one somatic cell into another without transitioning through a progenitor stage has emerged as a strategy to generate clinically relevant cell types. One cell type of interest is the pancreatic insulin-producing β cell whose loss and/or dysfunction leads to diabetes. To date it has been possible to create β-like cells from related endodermal cell types by forcing the expression of developmental transcription factors, but not from more distant cell lineages like fibroblasts. In light of the therapeutic benefits of choosing an accessible cell type as the cell of origin, in this study we set out to analyze the feasibility of transforming human skin fibroblasts into β-like cells. We describe how the timed-introduction of five developmental transcription factors (Neurog3, Pdx1, MafA, Pax4, and Nkx2-2) promotes conversion of fibroblasts toward a β-cell fate. Reprogrammed cells exhibit β-cell features including β-cell gene expression and glucose-responsive intracellular calcium mobilization. Moreover, reprogrammed cells display glucose-induced insulin secretion in vitro and in vivo. This work provides proof-of-concept of the capacity to make insulin-producing cells from human fibroblasts via transcription factor-mediated direct reprogramming.© 2023. The Author(s).
JTD Keywords: adult, beta-cells, differentiation, direct conversion, genes, in-vivo, islets, maturation, pancreatic progenitors, Pluripotent stem-cells
Tonelli, M, Catto, M, Sabaté, R, Francesconi, V, Laurini, E, Pricl, S, Pisani, L, Miniero, DV, Liuzzi, GM, Gatta, E, Relini, A, Gavín, R, Del Rio, JA, Sparatore, F, Carotti, A, (2023). Thioxanthenone-based derivatives as multitarget therapeutic leads for Alzheimer's disease EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY 250, 115169
A set of twenty-five thioxanthene-9-one and xanthene-9-one derivatives, that were previously shown to inhibit cholinesterases (ChEs) and amyloid β (Aβ40) aggregation, were evaluated for the inhibition of tau protein aggregation. All compounds exhibited a good activity, and eight of them (5-8, 10, 14, 15 and 20) shared comparable low micromolar inhibitory potency versus Aβ40 aggregation and human acetylcholinesterase (AChE), while inhibiting human butyrylcholinesterase (BChE) even at submicromolar concentration. Compound 20 showed outstanding biological data, inhibiting tau protein and Aβ40 aggregation with IC50 = 1.8 and 1.3 μM, respectively. Moreover, at 0.1-10 μM it also exhibited neuroprotective activity against tau toxicity induced by okadoic acid in human neuroblastoma SH-SY5Y cells, that was comparable to that of estradiol and PD38. In preliminary toxicity studies, these interesting results for compound 20 are somewhat conflicting with a narrow safety window. However, compound 10, although endowed with a little lower potency for tau and Aβ aggregation inhibition additionally demonstrated good inhibition of ChEs and rather low cytotoxicity. Compound 4 is also worth of note for its high potency as hBChE inhibitor (IC50 = 7 nM) and for the three order of magnitude selectivity versus hAChE. Molecular modelling studies were performed to explain the different behavior of compounds 4 and 20 towards hBChE. The observed balance of the inhibitory potencies versus the relevant targets indicates the thioxanthene-9-one derivatives as potential MTDLs for AD therapy, provided that the safety window will be improved by further structural variations, currently under investigation.Copyright © 2023 Elsevier Masson SAS. All rights reserved.
JTD Keywords: a? and tau aggregation inhibition, ache and bche inhibition, aggregation, alzheimer?s disease, butyrylcholinesterase, design, drugs, dual inhibitors, fibrillization, multitarget-directed ligands (mtdls), peptide, polyphenols, potent, rivatives, Ache and bche inhibition, Alzheimer's disease, Amyloid-beta, Aβ and tau aggregation inhibition, Multitarget-directed ligands (mtdls), Thioxanthene-9-one and xanthen-9-one de, Thioxanthene-9-one and xanthen-9-one derivatives
Ortiz, C, Klein, S, Reul, WH, Magdaleno, F, Gröschl, S, Dietrich, P, Schierwagen, R, Uschner, FE, Torres, S, Hieber, C, Meier, C, Kraus, N, Tyc, O, Brol, M, Zeuzem, S, Welsch, C, Poglitsch, M, Hellerbrand, C, Alfonso-Prieto, M, Mira, F, Keller, UAD, Tetzner, A, Moore, A, Walther, T, Trebicka, J, (2023). Neprilysin-dependent neuropeptide Y cleavage in the liver promotes fibrosis by blocking NPY-receptor 1 Cell Reports 42, 112059
Development of liver fibrosis is paralleled by contraction of hepatic stellate cells (HSCs), the main profibrotic hepatic cells. Yet, little is known about the interplay of neprilysin (NEP) and its substrate neuropeptide Y (NPY), a potent enhancer of contraction, in liver fibrosis. We demonstrate that HSCs are the source of NEP. Importantly, NPY originates majorly from the splanchnic region and is cleaved by NEP in order to terminate contraction. Interestingly, NEP deficiency (Nep-/-) showed less fibrosis but portal hypertension upon liver injury in two different fibrosis models in mice. We demonstrate the incremental benefit of Nep-/- in addition to AT1R blocker (ARB) or ACE inhibitors for fibrosis and portal hypertension. Finally, oral administration of Entresto, a combination of ARB and NEP inhibitor, decreased hepatic fibrosis and portal pressure in mice. These results provide a mechanistic rationale for translation of NEP-AT1R-blockade in human liver fibrosis and portal hypertension.Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.
JTD Keywords: activation, cirrhosis, cirrhotic rats, cp: cell biology, expression, hepatic stellate cell, identification, inhibition, mechanisms, modulation, neprilysin, neuropeptide y, neuropeptide y receptor 1, portal hypertension, portal-hypertension, web server, Renin-angiotensin system
Escartín, A, El Hauadi, K, Lanzalaco, S, Perez-Madrigal, MM, Armelin, E, Turon, P, Alemán, C, (2023). Preparation and Characterization of Functionalized Surgical Meshes for Early Detection of Bacterial Infections ACS Biomaterials Science & Engineering 9, 1104-1115
Isotactic polypropylene (i-PP) nonabsorbable surgical meshes are modified by incorporating a conducting polymer (CP) layer to detect the adhesion and growth of bacteria by sensing the oxidation of nicotinamide adenine dinucleotide (NADH), a metabolite produced by the respiration reactions of such microorganisms, to NAD+. A three-step process is used for such incorporation: (1) treat pristine meshes with low-pressure O2 plasma; (2) functionalize the surface with CP nanoparticles; and (3) coat with a homogeneous layer of electropolymerized CP using the nanoparticles introduced in (2) as polymerization nuclei. The modified meshes are stable and easy to handle and also show good electrochemical response. The detection by cyclic voltammetry of NADH within the interval of concentrations reported for bacterial cultures is demonstrated for the two modified meshes. Furthermore, Staphylococcus aureus and both biofilm-positive (B+) and biofilm-negative (B-) Escherichia coli cultures are used to prove real-time monitoring of NADH coming from aerobic respiration reactions. The proposed strategy, which offers a simple and innovative process for incorporating a sensor for the electrochemical detection of bacteria metabolism to currently existing surgical meshes, holds considerable promise for the future development of a new generation of smart biomedical devices to fight against post-operative bacterial infections.
JTD Keywords: adhesion, bacteria metabolism, behavior, biocompatibility, conducting polymer, electrochemical sensor, hernia repair, in-vivo, liquid, nadh detection, plasma treatment, prevention, reinforcement, sensor, smart meshes, Bacteria metabolism, Bacterial infections, Conducting polymer, Electrochemical sensor, Humans, Nad, Nadh detection, Nanoparticles, Oxidation-reduction, Plasma treatment, Polymers, Polypropylene mesh, Smart meshes, Surgical mesh
Acosta-Gutierrez, S, Buckley, J, Battaglia, G, (2023). The Role of Host Cell Glycans on Virus Infectivity: The SARS-CoV-2 Case Advanced Science 10, 2201853
Glycans are ubiquitously expressed sugars, coating the cell and protein surfaces. They are found on many proteins as either short and branched chains or long chains sticking out from special membrane proteins, known as proteoglycans. This sugar cushion, the glycocalyx, modulates specific interactions and protects the cell. Here it is shown that both the expression of proteoglycans and the glycans expressed on the surface of both the host and virus proteins have a critical role in modulating viral attachment to the cell. A mathematical model using SARS-Cov-2 as an archetypical virus to study the glycan role during infection is proposed. It is shown that this occurs via a tug-of-war of forces. On one side, the multivalent molecular recognition that viral proteins have toward specific host glycans and receptors. On the other side, the glycan steric repulsion that a virus must overcome to approach such specific receptors. By balancing both interactions, viral tropism can be predicted. In other words, the authors can map out the cells susceptible to virus infection in terms of receptors and proteoglycans compositions.© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.
JTD Keywords: binding, entry, glycocalyx, mechanisms, multiplexing, multivalency, nanoparticles, recognition, super-selectivity, viral infectivity, Functional receptor, Glycans, Glycocalyx, Multiplexing, Multivalency, Nanoparticles, Super-selectivity, Viral infectivity
Blanco-Fernandez, B, Ibanez-Fonesca, A, Orbanic, D, Ximenes-Carballo, C, Perez-Amodio, S, Rodriguez-Cabello, JC, Engel, E, (2023). Elastin-like Recombinamer Hydrogels as Platforms for Breast Cancer Modeling BIOMACROMOLECULES 24, 4408-4418
The involvement of the extracellular matrix (ECM) in tumor progression has motivated the development of biomaterials mimicking the tumor ECM to develop more predictive cancer models. Particularly, polypeptides based on elastin could be an interesting approach to mimic the ECM due to their tunable properties. Here, we demonstrated that elastin-like recombinamer (ELR) hydrogels can be suitable biomaterials to develop breast cancer models. This hydrogel was formed by two ELR polypeptides, one containing sequences biodegradable by matrix metalloproteinase and cyclooctyne and the other carrying arginylglycylaspartic acid and azide groups to allow cell adhesion, biodegradability, and suitable stiffness through "click-chemistry" cross-linking. Our findings show that breast cancer or nontumorigenic breast cells showed high viability and cell proliferation for up to 7 days. MCF7 and MCF10A formed spheroids whereas MDA-MB-231 formed cell networks, with the expression of ECM and high drug resistance in all cases, evidencing that ELR hydrogels are a promising biomaterial for breast cancer modeling.
JTD Keywords: clinical-trials, collagen i, discovery, mcf-7 cells, phenotype, progression, spheroids, translation, tumor microenvironment, Extracellular-matrix
Woythe, L, Tholen, MME, Rosier, BJHM, Albertazzi, L, (2023). Single-Particle Functionality Imaging of Antibody-Conjugated Nanoparticles in Complex Media ACS Applied Bio Materials 6, 171-181
The properties of nanoparticles (NPs) can change upon contact with serum components, occluding the NP surface by forming a biomolecular corona. It is believed that targeted NPs can lose their functionality due to this biological coating, thus losing specificity and selectivity toward target cells and leading to poor therapeutic efficiency. A better understanding of how the biomolecular corona affects NP ligand functionality is needed to maintain NP targeting capabilities. However, techniques that can quantify the functionality of NPs at a single-particle level in a complex medium are limited and often laborious in sample preparation, measurement, and analysis. In this work, the influence of serum exposure on the functionality of antibody-functionalized NPs was quantified using a straightforward total internal reflection fluorescence (TIRF) microscopy method and evaluated in cell uptake studies. The single-particle resolution of TIRF reveals the interparticle functionality heterogeneity and the substantial differences between NPs conjugated with covalent and noncovalent methods. Notably, only NPs covalently conjugated with a relatively high amount of antibodies maintain their functionality to a certain extent and still showed cell specificity and selectivity toward high receptor density cells after incubation in full serum. The presented study emphasizes the importance of single-particle functional characterization of NPs in complex media, contributing to the understanding and design of targeted NPs that retain their cell specificity and selectivity in biologically relevant conditions.
JTD Keywords: binding, biomolecular corona, cell selectivity, heterogeneity, nanoparticle conjugation, protein corona, tirf microscopy, Active targeting, Biomolecular corona, Cell selectivity, Heterogeneity, Nanoparticle conjugation, Tirf microscopy
Huetter, L, Kyndiah, A, Gomila, G, (2023). Analytical Physical Model for Organic Metal-Electrolyte-Semiconductor Capacitors Advanced Theory And Simulations 6, 2200698
This work presents the analytical physical modeling of undoped organic metal-electrolyte-semiconductor (OMES) capacitors in the framework of the Nernst-Planck-Poisson theory, including the presence of compact interfacial layers. This work derives an exact analytical solution, up to a quadrature, for the stationary electric potential and charge density distributions in both the semiconductor film and the electrolyte solution, and from them the sheet semiconductor charge and the stationary differential capacitance are obtained as a function of the applied voltage. The dependence of these magnitudes on the physical device parameters, like the ionic concentration of the electrolyte, the capacitance of the interfacial compact layers and the injected hole density is then analyzed. This work shows that ionic diffusive effects in the electrolyte can play an important role in the device response, inducing a broadening of the transition from the weak to the strong accumulation regimes. This fact can make that the strong accumulation regime is not achieved in OMES within the usual voltage operation range of these devices. The analytical solution is validated by means of finite element numerical calculations. The implications of the results obtained on the physics of electrolyte gated organic field effect transistors (EGOFETs) are discussed.
JTD Keywords: Analytical model, Equivalent-circuit model, Metal electrolyte semiconductor capacitors, Metal insulator semiconductor capacitors, Organic devices
Chausse, V, Iglesias, C, Bou-Petit, E, Ginebra, MP, Pegueroles, M, (2023). Chemical vs thermal accelerated hydrolytic degradation of 3D-printed PLLA/PLCL bioresorbable stents: Characterization and influence of sterilization POLYMER TESTING 117, 107817
Bioresorbable stents (BRS) are designed to provide initial sufficient mechanical support to prevent vessel recoil while being degraded until their complete resorption. Therefore, degradation rate of BRS plays a crucial role in successful stent performance. This work presents a complete study on the degradation of poly-llactic acid (PLLA) and poly(lactic-co-epsilon-caprolactone) (PLCL) stents fabricated by solvent-cast direct-writing (SC-DW) through two different accelerated assays: alkaline medium at 37 degrees C for 10 days and PBS at 50 degrees C for 4 months. On retrieval, degraded stents were characterized in terms of mass loss, molecular weight (Mw), thermal and mechanical properties. The results showed that under alkaline conditions, stents underwent surface erosion, whereas stents immersed in PBS at 50 degrees C experienced bulk degradation. M-n decrease was accurately described by the autocatalyzed kinetic model, with PLCL showing a degradation rate 1.5 times higher than PLLA. Additionally, stents were subjected to gamma-irradiation and ethylene oxide (EtO) sterilization. Whereas EtOsterilized stents remained structurally unaltered, gamma-irradiated stents presented severe deterioration as a result of extensive chain scission.
JTD Keywords: Acid, Behavior, Bioresorbable stents, Copolymer, Hydrolytic degradation, In-vitro degradation, Mechanical-properties, Molecular-weight, Poly(l-lactide), Poly-l-lactic acid, Poly-l-lactide, Scaffolds, Solvent-cast direct-writing, Sterilization
Guallar-Garrido, S, Campo-Perez, V, Perez-Trujillo, M, Cabrera, C, Senserrich, J, Sanchez-Chardi, A, Rabanal, RM, Gomez-Mora, E, Noguera-Ortega, E, Luquin, M, Julian, E, (2022). Mycobacterial surface characters remodeled by growth conditions drive different tumor-infiltrating cells and systemic IFN-gamma/IL-17 release in bladder cancer treatment OncoImmunology 11, 2051845
The mechanism of action of intravesical Mycobacterium bovis BCG immunotherapy treatment for bladder cancer is not completely known, leading to misinterpretation of BCG-unresponsive patients, who have scarce further therapeutic options. BCG is grown under diverse culture conditions worldwide, which can impact the antitumor effect of BCG strains and could be a key parameter of treatment success. Here, BCG and the nonpathogenic Mycobacterium brumae were grown in four culture media currently used by research laboratories and BCG manufacturers: Sauton-A60, -G15 and -G60 and Middlebrook 7H10, and used as therapies in the orthotopic murine BC model. Our data reveal that each mycobacterium requires specific culture conditions to induce an effective antitumor response. since higher survival rates of tumor-bearing mice were achieved using M. brumae-A60 and BCG-G15 than the rest of the treatments. M. brumae-A60 was the most efficacious among all tested treatments in terms of mouse survival, cytotoxic activity of splenocytes against tumor cells, higher systemic production of IL-17 and IFN-gamma, and bladder infiltration of selected immune cells such as ILCs and CD4(TEM). BCG-G15 triggered an antitumor activity based on a massive infiltration of immune cells, mainly CD3(+) (CD4(+) and CD8(+)) T cells, together with high systemic IFN-gamma release. Finally, a reduced variety of lipids was strikingly observed in the outermost layer of M. brumae-A60 and BCG-G15 compared to the rest of the cultures, suggesting an influence on the antitumor immune response triggered. These findings contribute to understand how mycobacteria create an adequate niche to help the host subvert immunosuppressive tumor actions.
JTD Keywords: bcg, innate immune response, innate-lymphoid cells, lipid, non-muscle invasive, Bcg, Calmette-guerin bcg, Glycerol, Identification, Immune-response, Innate immune response, Innate-lymphoid cells, Lipid, Lipids, Mycolic acids, Neutral-red, Non-muscle invasive, Phenolic glycolipids, Tuberculosis, Tumor microenvironment, Virulence
Lagunas, A, Belloir, C, Briand, L, Gorostiza, P, Samitier, J, (2022). Determination of the nanoscale electrical properties of olfactory receptor hOR1A1 and their dependence on ligand binding: Towards the development of capacitance-operated odorant biosensors BIOSENSORS & BIOELECTRONICS 218, 114755
The transduction of odorant binding into cellular signaling by olfactory receptors (ORs) is not understood and knowing its mechanism would enable developing new pharmacology and biohybrid electronic detectors of volatile organic compounds bearing high sensitivity and selectivity. The electrical characterization of ORs in bulk experiments is subject to microscopic models and assumptions. We have directly determined the nanoscale electrical properties of ORs immobilized in a fixed orientation, and their change upon odorant binding, using electrochemical scanning tunneling microscopy (EC-STM) in near-physiological conditions. Recordings of current versus time, distance, and electrochemical potential allows determining the OR impedance parameters and their dependence with odorant binding. Our results allow validating OR structural-electrostatic models and their functional activation processes, and anticipating a novel macroscopic biosensor based on ORs.Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.
JTD Keywords: electrochemical scanning tunneling, electrochemical scanning tunneling microscopy (ec-stm), microscopy (ec-stm), neurons, odorant binding, olfactory receptors (ors), open-circuit voltage(voc), Olfactory receptors (ors), Open-circuit voltage (v(oc)), Transport
Ferrer, I, Andrés-Benito, P, Carmona, M, del Rio, JA, (2022). Common and Specific Marks of Different Tau Strains Following Intra-Hippocampal Injection of AD, PiD, and GGT Inoculum in hTau Transgenic Mice INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 23, 15940
Heterozygous hTau mice were used for the study of tau seeding. These mice express the six human tau isoforms, with a high predominance of 3Rtau over 4Rtau. The following groups were assessed: (i) non-inoculated mice aged 9 months (n = 4); (ii) Alzheimer's Disease (AD)-inoculated mice (n = 4); (iii) Globular Glial Tauopathy (GGT)-inoculated mice (n = 4); (iv) Pick's disease (PiD)-inoculated mice (n = 4); (v) control-inoculated mice (n = 4); and (vi) inoculated with vehicle alone (n = 2). AD-inoculated mice showed AT8-immunoreactive neuronal pre-tangles, granular aggregates, and dots in the CA1 region of the hippocampus, dentate gyrus (DG), and hilus, and threads and dots in the ipsilateral corpus callosum. GGT-inoculated mice showed unique or multiple AT8-immunoreactive globular deposits in neurons, occasionally extended to the proximal dendrites. PiD-inoculated mice showed a few loose pre-tangles in the CA1 region, DG, and cerebral cortex near the injection site. Coiled bodies were formed in the corpus callosum in AD-inoculated mice, but GGT-inoculated mice lacked globular glial inclusions. Tau deposits in inoculated mice co-localized active kinases p38-P and SAPK/JNK-P, thus suggesting active phosphorylation of the host tau. Tau deposits were absent in hTau mice inoculated with control homogenates and vehicle alone. Deposits in AD-inoculated hTau mice contained 3Rtau and 4Rtau; those in GGT-inoculated mice were mainly stained with anti-4Rtau antibodies, but a small number of deposits contained 3Rtau. Deposits in PiD-inoculated mice were stained with anti-3Rtau antibodies, but rare neuronal, thread-like, and dot-like deposits showed 4Rtau immunoreactivity. These findings show that tau strains produce different patterns of active neuronal seeding, which also depend on the host tau. Unexpected 3Rtau and 4Rtau deposits after inoculation of homogenates from 4R and 3R tauopathies, respectively, suggests the regulation of exon 10 splicing of the host tau during the process of seeding, thus modulating the plasticity of the cytoskeleton.
JTD Keywords: alzheimer's disease (ad), alzheimers-disease, brain, corticobasal degeneration, globular glial tauopathy (ggt), htau, isoforms, pathological tau, pick's disease (pid), picks-disease, propagation, protein, seeding, tau splicing, tauopathy, Alzheimer disease, Alzheimer’s disease (ad), Animals, Brain, Globular glial tauopathy (ggt), Hippocampus, Htau, Humans, Mice, Mice, transgenic, Paired helical filaments, Pick disease of the brain, Pick’s disease (pid), Seeding, Tau, Tau proteins, Tau splicing, Tauopathies
Badiola-Mateos, M, Osaki, T, Kamm, RD, Samitier, J, (2022). In vitro modelling of human proprioceptive sensory neurons in the neuromuscular system Scientific Reports 12, 21318
Proprioceptive sensory neurons (pSN) are an essential and undervalued part of the neuromuscular circuit. A protocol to differentiate healthy and amyotrophic lateral sclerosis (ALS) human neural stem cells (hNSC) into pSN, and their comparison with the motor neuron (MN) differentiation process from the same hNSC sources, facilitated the development of in vitro co-culture platforms. The obtained pSN spheroids cultured interact with human skeletal myocytes showing the formation of annulospiral wrapping-like structures between TrkC + neurons and a multinucleated muscle fibre, presenting synaptic bouton-like structures in the contact point. The comparative analysis of the genetic profile performed in healthy and sporadic ALS hNSC differentiated to pSN suggested that basal levels of ETV1, critical for motor feedback from pSN, were much lower for ALS samples and that the differences between healthy and ALS samples, suggest the involvement of pSN in ALS pathology development and progression.© 2022. The Author(s).
JTD Keywords: Amyotrophic-lateral-sclerosis,pluripotent stem-cells,peripheral nervous-system,stretch reflex arc,mechanosensory circuit,cellular-localization,molecular-cloning,motor-neurons,muscle,expressio
Fischer, NG, Aparicio, C, (2022). Junctional epithelium and hemidesmosomes: Tape and rivets for solving the “percutaneous device dilemma” in dental and other permanent implants Bioactive Materials 18, 178-198
The percutaneous device dilemma describes etiological factors, centered around the disrupted epithelial tissue surrounding non-remodelable devices, that contribute to rampant percutaneous device infection. Natural percutaneous organs, in particular their extracellular matrix mediating the “device”/epithelium interface, serve as exquisite examples to inspire longer lasting long-term percutaneous device design. For example, the tooth's imperviousness to infection is mediated by the epithelium directly surrounding it, the junctional epithelium (JE). The hallmark feature of JE is formation of hemidesmosomes, cell/matrix adhesive structures that attach surrounding oral gingiva to the tooth's enamel through a basement membrane. Here, the authors survey the multifaceted functions of the JE, emphasizing the role of the matrix, with a particular focus on hemidesmosomes and their five main components. The authors highlight the known (and unknown) effects dental implant – as a model percutaneous device – placement has on JE regeneration and synthesize this information for application to other percutaneous devices. The authors conclude with a summary of bioengineering strategies aimed at solving the percutaneous device dilemma and invigorating greater collaboration between clinicians, bioengineers, and matrix biologists. © 2022 The Authors
JTD Keywords: amino-acid-sequence, bioinspired surfaces, cell-secreted protein, growth-factor receptor, hemidesmosome, integrin beta-4 subunit, junctional epithelium, keratinocyte-derived chemokine, laminin-binding integrins, marginal bone loss, percutaneous device, percutaneous implant, pressure wound therapy, soft-tissue integration, Bioinspired surfaces, Bullous-pemphigoid antigen, Hemidesmosome, Junctional epithelium, Percutaneous device, Percutaneous implant
Fortunato, IC, Sunyer, R, (2022). The Forces behind Directed Cell Migration Biophysica 2, 548-563
Directed cell migration is an essential building block of life, present when an embryo develops, a dendritic cell migrates toward a lymphatic vessel, or a fibrotic organ fails to restore its normal parenchyma. Directed cell migration is often guided by spatial gradients in a physicochemical property of the cell microenvironment, such as a gradient in chemical factors dissolved in the medium or a gradient in the mechanical properties of the substrate. Single cells and tissues sense these gradients, establish a back-to-front polarity, and coordinate the migration machinery accordingly. Central to these steps we find physical forces. In some cases, these forces are integrated into the gradient sensing mechanism. Other times, they transmit information through cells and tissues to coordinate a collective response. At any time, they participate in the cellular migratory system. In this review, we explore the role of physical forces in gradient sensing, polarization, and coordinating movement from single cells to multicellular collectives. We use the framework proposed by the molecular clutch model and explore to what extent asymmetries in the different elements of the clutch can lead to directional migration.
JTD Keywords: Cell migration, Cell traction forces, Chemotaxis, Contact guidance, Curvotaxis, Cytoskeleton, Durotaxis, Extracellular-matrix, Focal adhesions, Guidance, Haptotaxis, Leading-edge, Mechanotaxis, Membrane tension, Molecular clutch model, Myosin-ii, Reduced inequalities, Rigidity, Stress fibers, Traction
Wang, L, Huang, Y, Xu, H, Chen, S, Chen, H, Lin, Y, Wang, X, Liu, X, Sánchez, S, Huang, X, (2022). Contaminants-fueled laccase-powered Fe3O4@SiO2 nanomotors for synergistical degradation of multiple pollutants Materials Today Chemistry 26, 101059
Although an increasing number of micro/nanomotors have been designed for environmental remediation in the past decade, the construction of contaminants-fueled nanomotors for synergistically degrading multiple pollutants simultaneously remains a challenge. Herein, laccase-powered Fe3O4@silica nanomotors are fabricated, assisted with lipase enzyme for the enhanced degradation of multiple contaminants using the contaminants themselves as fuels. Notably, we demonstrate that representative industrial phenols and polycyclic aromatic pollutants possess the ability of triggering the enhanced Brownian motion of laccase nanomotors (De of 1.16 mu m(2)/s in 220 mu M biphenol A (BPA), 1.40 mu m(2)/s in 375 mu M Congo red (CR)). Additionally, the k(cat) value of lipase-assisted laccase-powered nanomotors increased over 1.4 times, enhancing their Brownian motion, while leading to the efficient degradation of multiple contaminants such as BPA, CR, and triacetin droplets within 40 min, simultaneously. Ultimately, the lipase-assisted laccase nanomotors exhibit great advantages over free laccase, free lipase, lipase nanomotors, or laccase nanomotors in K-m, k(cat), catalytic stability, recycling property, and the degradation efficiency of contaminants. Therefore, our work further broadens the library of enzyme-powered nanomotors and provides deep insights in synergistical enzymatic catalysis, thus paving avenues for environmental remediation based on enzyme-powered micro/nanomotors. (C) 2022 Elsevier Ltd. All rights reserved.
JTD Keywords: core, dye, environmental remediation, enzyme catalysis, hybrid, light, microspheres, motors, pollutants removal, propulsion, removal, self-propulsion, shell, Core, Dye, Environmental remediation, Enzyme catalysis, Hybrid, Light, Micro/nanomotors, Micromotors, Microspheres, Motors, Pollutants removal, Propulsion, Removal, Self-propulsion, Shell
Arnau, M, Sans, J, Turon, P, Alemán, C, (2022). Decarbonization of Polluted Air by SolarDriven CO2 Conversion into Ethanol Using Polarized Animal Solid Waste as Catalyst ADVANCED SUSTAINABLE SYSTEMS 6, 2200283
Gomila, AMJ, Pérez-Mejías, G, Nin-Hill, A, Guerra-Castellano, A, Casas-Ferrer, L, Ortiz-Tescari, S, Díaz-Quintana, A, Samitier, J, Rovira, C, De la Rosa, MA, Díaz-Moreno, I, Gorostiza, P, Giannotti, M, Lagunas, A, (2022). Phosphorylation disrupts long-distance electron transport in cytochrome c Nature Communications 13, 7100
It has been recently shown that electron transfer between mitochondrial cytochrome c and the cytochrome c1 subunit of the cytochrome bc1 can proceed at long-distance through the aqueous solution. Cytochrome c is thought to adjust its activity by changing the affinity for its partners via Tyr48 phosphorylation, but it is unknown how it impacts the nanoscopic environment, interaction forces, and long-range electron transfer. Here, we constrain the orientation and separation between cytochrome c1 and cytochrome c or the phosphomimetic Y48pCMF cytochrome c, and deploy an array of single-molecule, bulk, and computational methods to investigate the molecular mechanism of electron transfer regulation by cytochrome c phosphorylation. We demonstrate that phosphorylation impairs long-range electron transfer, shortens the long-distance charge conduit between the partners, strengthens their interaction, and departs it from equilibrium. These results unveil a nanoscopic view of the interaction between redox protein partners in electron transport chains and its mechanisms of regulation.© 2022. The Author(s).
JTD Keywords: apoptosis, binding, cardiolipin, complex, dynamics, force, respiration, structural basis, tyrosine phosphorylation, Histone chaperone activity
Ulldemolins, A, Jurado, A, Herranz-Diez, C, Gavara, N, Otero, J, Farré, R, Almendros, I, (2022). Lung Extracellular Matrix Hydrogels-Derived Vesicles Contribute to Epithelial Lung Repair Polymers 14, 4907
The use of physiomimetic decellularized extracellular matrix-derived hydrogels is attracting interest since they can modulate the therapeutic capacity of numerous cell types, including mesenchymal stromal cells (MSCs). Remarkably, extracellular vesicles (EVs) derived from MSCs display similar functions as their parental cells, mitigating tissue damage in lung diseases. However, recent data have shown that ECM-derived hydrogels could release other resident vesicles similar to EVs. Here, we aim to better understand the contribution of EVs and ECM-vesicles released from MSCs and/or lung-derived hydrogel (L-HG) in lung repair by using an in vitro lung injury model. L-HG derived-vesicles and MSCs EVs cultured either in L-HG or conventional plates were isolated and characterized. The therapeutic capacity of vesicles obtained from each experimental condition was tested by using an alveolar epithelial wound-healing assay. The number of ECM-vesicles released from acellular L-HG was 10-fold greater than EVs from conventional MSCs cell culture revealing that L-HG is an important source of bioactive vesicles. MSCs-derived EVs and L-HG vesicles have similar therapeutic capacity in lung repair. However, when wound closure rate was normalized by total proteins, the MSCs-derived EVs shows higher therapeutic potential to those released by L-HG. The EVs released from L-HG must be considered when HG is used as substrate for cell culture and EVs isolation.
JTD Keywords: cell, extracellular vesicles, hydrogel, lung epithelial cells, lung repair, mesenchymal stem cells, Extracellular matrix, Extracellular vesicles, Hydrogel, Lung epithelial cells, Lung repair, Mesenchymal stem cells, Respiratory-distress-syndrome
Burgués, J, Doñate, S, Esclapez, MD, Saúco, L, Marco, S, (2022). Characterization of odour emissions in a wastewater treatment plant using a drone-based chemical sensor system SCIENCE OF THE TOTAL ENVIRONMENT 846, 157290
Conventionally, odours emitted by different sources present in wastewater treatment plants (WWTPs) are measured by dynamic olfactometry, where a human panel sniffs and analyzes air bags collected from the plant. Although the method is considered the gold standard, the process is costly, slow, and infrequent, which does not allow operators to quickly identify and respond to problems. To better monitor and map WWTP odour emissions, here we propose a small rotary-wing drone equipped with a lightweight (1.3-kg) electronic nose. The "sniffing drone" sucks in air via a ten-meter (33-foot) tube and delivers it to a sensor chamber where it is analyzed in real-time by an array of 21 gas sensors. From the sensor signals, machine learning (ML) algorithms predict the odour concentration that a human panel using the EN13725 methodology would report. To calibrate and validate the predictive models, the drone also carries a remotely controlled sampling device (compliant with EN13725:2022) to collect sample air in bags for post-flight dynamic olfactometry. The feasibility of the proposed system is assessed in a WWTP in Spain through several measurement campaigns covering diverse operating regimes of the plant and meteorological conditions. We demonstrate that training the ML algorithms with dynamic (transient) sensor signals measured in flight conditions leads to better performance than the traditional approach of using steady-state signals measured in the lab via controlled exposures to odour bags. The comparison of the electronic nose predictions with dynamic olfactometry measurements indicates a negligible bias between the two measurement techniques and 95 % limits of agreement within a factor of four. This apparently large disagreement, partly caused by the high uncertainty of olfactometric measurements (typically a factor of two), is more than offset by the immediacy of the predictions and the practical advantages of using a drone-based system.Copyright © 2022. Published by Elsevier B.V.
JTD Keywords: calibration, chemical sensors, drone, dynamic olfactometry, electronic nose, odourquantification, olfaction, volatile organic-compounds, wwtp, Calibration, Chemical sensors, Drone, Dynamic olfactometry, Electronic nose, Environmental monitoring, Odour quantification, Olfaction, Variable selection methods, Wwtp
Ahmad, J, Ellis, C, Leech, R, Voytek, B, Garces, P, Jones, E, Buitelaar, J, Loth, E, dos Santos, FP, Amil, AF, Verschure, PFMJ, Murphy, D, McAlonan, G, (2022). From mechanisms to markers: novel noninvasive EEG proxy markers of the neural excitation and inhibition system in humans Translational Psychiatry 12, 467
Brain function is a product of the balance between excitatory and inhibitory (E/I) brain activity. Variation in the regulation of this activity is thought to give rise to normal variation in human traits, and disruptions are thought to potentially underlie a spectrum of neuropsychiatric conditions (e.g., Autism, Schizophrenia, Downs' Syndrome, intellectual disability). Hypotheses related to E/I dysfunction have the potential to provide cross-diagnostic explanations and to combine genetic and neurological evidence that exists within and between psychiatric conditions. However, the hypothesis has been difficult to test because: (1) it lacks specificity-an E/I dysfunction could pertain to any level in the neural system- neurotransmitters, single neurons/receptors, local networks of neurons, or global brain balance - most researchers do not define the level at which they are examining E/I function; (2) We lack validated methods for assessing E/I function at any of these neural levels in humans. As a result, it has not been possible to reliably or robustly test the E/I hypothesis of psychiatric disorders in a large cohort or longitudinal patient studies. Currently available, in vivo markers of E/I in humans either carry significant risks (e.g., deep brain electrode recordings or using Positron Emission Tomography (PET) with radioactive tracers) and/or are highly restrictive (e.g., limited spatial extent for Transcranial Magnetic Stimulation (TMS) and Magnetic Resonance Spectroscopy (MRS). More recently, a range of novel Electroencephalography (EEG) features has been described, which could serve as proxy markers for E/I at a given level of inference. Thus, in this perspective review, we survey the theories and experimental evidence underlying 6 novel EEG markers and their biological underpinnings at a specific neural level. These cheap-to-record and scalable proxy markers may offer clinical utility for identifying subgroups within and between diagnostic categories, thus directing more tailored sub-grouping and, therefore, treatment strategies. However, we argue that studies in clinical populations are premature. To maximize the potential of prospective EEG markers, we first need to understand the link between underlying E/I mechanisms and measurement techniques.
JTD Keywords: Cortical networks, Direction selectivity, Excitation/inhibition balance, Fast network oscillations, Gaba concentration, Gamma oscillation frequency, Neuronal oscillations, Range temporal correlations, Self-organized criticality, Theta-oscillations
Campo-Perez, V, Guallar-Garrido, S, Luquin, M, Sanchez-Chardi, A, Julian, E, (2022). The High Plasticity of Nonpathogenic Mycobacterium brumae Induces Rapid Changes in Its Lipid Profile during Pellicle Maturation: The Potential of This Bacterium as a Versatile Cell Factory for Lipid Compounds of Therapeutic Interest INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 23, 13609
The immunomodulatory potential of mycobacteria to be used for therapeutic purposes varies by species and culture conditions and is closely related to mycobacterial lipid composition. Although the lipids present in the mycobacterial cell wall are relevant, lipids are mainly stored in intracellular lipid inclusions (ILIs), which have emerged as a crucial structure in understanding mycobacteria-host interaction. Little is known about ILI ultrastructure, production, and composition in nonpathogenic species. In this study, we compared the lipid profiles of the nonpathogenic immunomodulatory agent Mycobacterium brumae during pellicle maturation under different culture conditions with qualitative and quantitative approaches by using high-resolution imaging and biochemical and composition analyses to understand ILI dynamics. The results showed wax esters, mainly in early stages of development, and acylglycerols in mature ILI composition, revealing changes in dynamics, amount, and morphometry, depending on pellicle maturation and the culture media used. Low-glycerol cultures induced ILIs with lower molecular weights which were smaller in size in comparison with the ILIs produced in glycerol-enriched media. The data also indicate the simple metabolic plasticity of lipid synthesis in M. brumae, as well as its high versatility in generating different lipid profiles. These findings provide an interesting way to enhance the production of key lipid structures via the simple modulation of cell culture conditions.
JTD Keywords: cell wall, electron microscopy, intrabacterial, lipid inclusions, mycobacterium, Bodies, Cell wall, Electron microscopy, Growth, In-vitro, Intrabacterial, Lipid inclusions, Mycobacterium, Prokaryotes, Triacylglycerol, Tuberculosis, Ultrastructural imaging, Virulence, Wax esters
Sans, J, Arnau, M, Sanz, V, Turon, P, Aleman, C, (2022). Fine-tuning of polarized hydroxyapatite for the catalytic conversion of dinitrogen to ammonium under mild conditions CHEMICAL ENGINEERING JOURNAL 446, 137440
Polarized hydroxyapatite (p-HAp), a calcium phosphate catalyst obtained at high temperature under intense electric field, has been used for the synthesis of ammonium starting from N2 and liquid water at low pressure (<6 bar) and temperatures below 120 C. The success of the nitrogen fixation process has been demonstrated by isotope labelling experiments using 15N2. Considering the optimal reaction conditions for the production of ammonium, the yield is as high as 154.6 +/- 25.8 mu mol/g of catalyst. The proposed synthesis exhibits three important advantages for its utilization in green chemistry environmental processes related to the recycling of polluted air. These are: i) the catalysts converts CO2 into valuable chemical products in addition of transforming N2 in ammonium; ii) the final energy balance is very favorable since no external electrical field is necessary to promote nitrogen and carbon fixation reactions; and iii) products are easily transferred to water favoring their extraction and avoiding the saturation of the catalyst.
JTD Keywords: Adsorbed nitrogen, Air pollution, Amino-acids, Electrophotosynthesis, Environmental process, Facile synthesis, Fixation, Functionalization, Hydroxyapatite, Nitride, Nitrogen reduction, Polarized catalyst
Morla-Folch, J, Vargas-Nadal, G, Fuentes, E, Illa-Tuset, S, Koeber, M, Sissa, C, Pujals, S, Painelli, A, Veciana, J, Faraudo, J, Belfield, KD, Albertazzi, L, Ventosa, N, (2022). Ultrabright Foster Resonance Energy Transfer Nanovesicles: The Role of Dye Diffusion CHEMISTRY OF MATERIALS 34, 8517-8527
The development of contrast agents based on fluorescent nanoparticles with high brightness and stability is a key factor to improve the resolution and signal-to-noise ratio of current fluorescence imaging techniques. However, the design of bright fluorescent nanoparticles remains challenging due to fluorescence self-quenching at high concentrations. Developing bright nanoparticles showing FRET emission adds several advantages to the system, including an amplified Stokes shift, the possibility of ratiometric measurements, and of verifying the nanoparticle stability. Herein, we have developed Forster resonance energy transfer (FRET)-based nanovesicles at different dye loadings and investigated them through complementary experimental techniques, including conventional fluorescence spectroscopy and super-resolution microscopy supported by molecular dynamics calculations. We show that the optical properties can be modulated by dye loading at the nanoscopic level due to the dye's molecular diffusion in fluid-like membranes. This work shows the first proof of a FRET pair dye's dynamism in liquid-like membranes, resulting in optimized nanoprobes that are 120-fold brighter than QDot 605 and exhibit >80% FRET efficiency with vesicle-to-vesicle variations that are mostly below 10%.
JTD Keywords: Bright, Dendrimers, Fluorescent, In-vivo, Nanoparticles, Nir, Particles
Sala-Jarque, J, Zimkowska, K, Avila, J, Ferrer, I, del Rio, JA, (2022). Towards a Mechanistic Model of Tau-Mediated Pathology in Tauopathies: What Can We Learn from Cell-Based In Vitro Assays? INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 23, 11527
Tauopathies are a group of neurodegenerative diseases characterized by the hyperphosphorylation and deposition of tau proteins in the brain. In Alzheimer's disease, and other related tauopathies, the pattern of tau deposition follows a stereotypical progression between anatomically connected brain regions. Increasing evidence suggests that tau behaves in a "prion-like" manner, and that seeding and spreading of pathological tau drive progressive neurodegeneration. Although several advances have been made in recent years, the exact cellular and molecular mechanisms involved remain largely unknown. Since there are no effective therapies for any tauopathy, there is a growing need for reliable experimental models that would provide us with better knowledge and understanding of their etiology and identify novel molecular targets. In this review, we will summarize the development of cellular models for modeling tau pathology. We will discuss their different applications and contributions to our current understanding of the "prion-like" nature of pathological tau.
JTD Keywords: neurodegeneration, seeding, spreading, Culture model, Efficient generation, Extracellular tau, Familial alzheimers-disease, Microtubule-associated protein, Mouse model, Neurodegeneration, Neurofibrillary tangles, Paired helical filaments, Pathogenic tau, Pluripotent stem-cells, Seeding, Spreading, Tauopathies
Fernandez-Vazquez, J, Cabrer-Panes, JD, Aberg, A, Juarez, A, Madrid, C, Gaviria-Cantin, T, Fernandez-Coll, L, Vargas-Sinisterra, AF, Jimenez, CJ, Balsalobre, C, (2022). ppGpp, the General Stress Response Alarmone, Is Required for the Expression of the alpha-Hemolysin Toxin in the Uropathogenic Escherichia coli Isolate, J96 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 23, 12256
ppGpp is an intracellular sensor that, in response to different types of stress, coordinates the rearrangement of the gene expression pattern of bacteria to promote adaptation and survival to new environmental conditions. First described to modulate metabolic adaptive responses, ppGpp modulates the expression of genes belonging to very diverse functional categories. In Escherichia coli, ppGpp regulates the expression of cellular factors that are important during urinary tract infections. Here, we characterize the role of this alarmone in the regulation of the hlyCABD(II) operon of the UPEC isolate J96, encoding the toxin alpha-hemolysin that induces cytotoxicity during infection of bladder epithelial cells. ppGpp is required for the expression of the alpha-hemolysin encoded in hlyCABD(II) by stimulating its transcriptional expression. Prototrophy suppressor mutations in a ppGpp-deficient strain restore the alpha-hemolysin expression from this operon to wild-type levels, confirming the requirement of ppGpp for its expression. ppGpp stimulates hlyCABD(II) expression independently of RpoS, RfaH, Zur, and H-NS. The expression of hlyCABD(II) is promoted at 37 degrees C and at low osmolarity. ppGpp is required for the thermoregulation but not for the osmoregulation of the hlyCABD(II) operon. Studies in both commensal and UPEC isolates demonstrate that no UPEC specific factor is strictly required for the ppGpp-mediated regulation described. Our data further support the role of ppGpp participating in the coordinated regulation of the expression of bacterial factors required during infection.
JTD Keywords: gene regulation, ppgpp, upec, Alpha-hemolysin, Bacterial signal molecule, Determinants, Environmental-regulation, Gene regulation, H-ns, Ppgpp, Protein, Regulator, Rfah, Secretion, Transcription, Upec, Virulence, Α-hemolysin
Hodásová, L, Morena, AG, Tzanov, T, Fargas, G, Llanes, L, Alemán, C, Armelin, E, (2022). 3D-Printed Polymer-Infiltrated Ceramic Network with Antibacterial Biobased Silver Nanoparticles ACS Applied Bio Materials 5, 4803-4813
This work aimed at the antimicrobial functionalization of 3D-printed polymer-infiltrated biomimetic ceramic networks (PICN). The anti-microbial properties of the polymer-ceramic composites were achieved by coating them with human-and environmentally safe silver nanoparticles trapped in a phenolated lignin matrix (Ag@PL NPs). Lignin was enzymatically phenolated and used as a biobased reducing agent to obtain stable Ag@PL NPs, which were then formulated in a silane (gamma-MPS) solution and deposited to the PICN surface. The presence of the NPs and their proper attachment to the surface were analyzed with spectroscopic methods (FTIR and Raman) and X-ray photoelectron spectroscopy (XPS). Homogeneous distribution of 13.4 +/- 3.2 nm NPs was observed in the transmission electron microscopy (TEM) images. The functionalized samples were tested against Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria, validating their antimicrobial efficiency in 24 h. The bacterial reduction of S. aureus was 90% in comparison with the pristine surface of PICN. To confirm that the Ag-functionalized PICN scaffold is a safe material to be used in the biomedical field, its biocompatibility was demonstrated with human fibroblast (BJ-5ta) and keratinocyte (HaCaT) cells, which was higher than 80% in both cell lines.
JTD Keywords: accuracy, antibacterial activity, disease, facile, laccase enzyme, lignin, polyacrylates, polymer-infiltrated ceramic network, silver nanoparticles, zirconia, Mechanical-properties, Mechanical-properties,zirconia,lignin,accuracy,disease,facil, Polymer-infiltrated ceramic network, Polymer-infiltrated ceramic network,polyacrylates,lignin,laccase enzyme,silver nanoparticles,antibacterial activit, Silver nanoparticles
López-Carral, H, Blancas-Muñoz, M, Mura, A, Omedas, P, España-Cumellas, A, Martínez-Bueno, E, Milliken, N, Moore, P, Haque, L, Gilroy, S, Verschure, PFMJ, (2022). A Virtual Reality System for the Simulation of Neurodiversity Lecture Notes in Networks and Systems 236, 523-531
Autism is a neurodevelopmental disorder characterized by deficits in social communication and repetitive patterns of behavior. Individuals affected by Autism Spectrum Disorder (ASD) may face overwhelming sensory hypersensitivities that hamper their everyday life. In order to promote awareness about neurodiversity among the neurotypical population, we have developed an interactive virtual reality simulation to experience the oversensory stimulation that an individual with autism spectrum disorder may experience in a natural environment. In this experience, we project the user in a first-person perspective in a classroom where a teacher is presenting a lecture. As the user explores the classroom and attends the lecture, he/she is confronted with sensory distortions which are commonly experienced by persons with ASD. We provide the users with a virtual reality headset with motion tracking, two wireless controllers for interaction, and a wristband for physiological data acquisition to create a closed feedback loop. This wearable device measures blood volume pulse (BVP) and electrodermal activity (EDA), which we use to perform online estimations of the arousal levels of users as they respond to the virtual stimuli. We use this information to modulate the intensity of auditory and visual stimuli simulating a vicious cycle in which increased arousal translates into increased oversensory stimulation. Here, we present the architecture and technical implementation of this system.
JTD Keywords: autism spectrum disorder, neurodiversity, physiology, Autism, Autism spectrum disorder, Neurodiversity, Physiology, Virtual reality
Caballeria, E, Maier, M, Balcells-Oliveró, M, López-Pelayo, H, Oliveras, C, Ballester, BR, Verschure, PFMJ, Gual, A, (2022). Rehabilitation Gaming System for Alcohol-Related Cognitive Impairment: A Pilot Usability Study ALCOHOL AND ALCOHOLISM 57, 595-601
Aims: Cognitive impairment in patients with alcohol use disorder (AUD) is highly prevalent, and it negatively impacts treatment outcome. However, this condition is neither systematically assessed nor treated. Thus, we aimed to explore the usability of a virtual reality-based protocol ('Rehabilitation Gaming System', RGS) for patients with AUD. Methods: Twenty AUD patients (50% also cognitive impairment) underwent a single session of the RGS protocol (four cognitive training tasks, 10 minutes each). System Usability Scale (SUS) and Post-Study System Usability Questionnaire (PSSUQ) were applied to assess the RGS usability and patients' satisfaction with it. Also, the Perceived Competence Scale was administered to assess the patients' feelings of competence when using the training protocol. Comparisons of the responses to these questionnaires were performed between AUD patients with cognitive impairment and those without cognitive impairment. Results: RGS usability was very positively rated (median SUS score = 80, Interquartile Range, IQR = 68.13-86-88). No significant differences were found in the median SUS scores for any of the sociodemographic or clinical variables, excepting for gender (women median score = 85; IQR = 80-94.38 vs. men median score = 71.25; IQR = 61.25-89.25; P-value = 0.035). The quality of the information provided by the RGS training scenarios and the usability were positively rated (PSSUQ), and patients experienced high feelings of competence. Conclusions: The RGS has been found to be usable in the short term and patients with AUD stated to be satisfied with it. Future larger, randomized trials are needed to explore the effectiveness of this tool to help overcome the cognitive deficits in AUD patients. Short Summary: Although cognitive impairments are highly prevalent in alcohol use disorder (AUD), no long-term gold standard intervention has yet been identified. The Rehabilitation Gaming System (virtual reality-based cognitive training protocol) has shown short-term high usability in AUD. Its effectiveness in providing engaging, long-term cognitive rehabilitation in AUD should be further assessed.
JTD Keywords: Addiction, Brain-damage, Deficits, Impact, Neurocognitive impairment, Therapy
Tas, B, Kalk, NJ, Lozano-Garcia, M, Rafferty, GF, Cho, PSP, Kelleher, M, Moxham, J, Strang, J, Jolley, C, (2022). Risk factors for respiratory depression in Opioid Use Disorder EUROPEAN RESPIRATORY JOURNAL 60, 2791
Safi, W, Marco, A, Moya, D, Prado, P, Garreta, E, Montserrat, N, (2022). Assessing kidney development and disease using kidney organoids and CRISPR engineering Frontiers in Cell and Developmental Biology 10, 948395
The differentiation of human pluripotent stem cells (hPSCs) towards organoids is one of the biggest scientific advances in regenerative medicine. Kidney organoids have not only laid the groundwork for various organ-like tissue systems but also provided insights into kidney embryonic development. Thus, several protocols for the differentiation of renal progenitors or mature cell types have been established. Insights into the interplay of developmental pathways in nephrogenesis and determination of different cell fates have enabled the in vitro recapitulation of nephrogenesis. Here we first provide an overview of kidney morphogenesis and patterning in the mouse model in order to dissect signalling pathways that are key to define culture conditions sustaining renal differentiation from hPSCs. Secondly, we also highlight how genome editing approaches have provided insights on the specific role of different genes and molecular pathways during renal differentiation from hPSCs. Based on this knowledge we further review how CRISPR/Cas9 technology has enabled the recapitulation and correction of cellular phenotypes associated with human renal disease. Last, we also revise how the field has positively benefited from emerging technologies as single cell RNA sequencing and discuss current limitations on kidney organoid technology that will take advantage from bioengineering solutions to help standardizing the use of this model systems to study kidney development and disease.Copyright © 2022 Safi, Marco, Moya, Prado, Garreta and Montserrat.
JTD Keywords: crispr, directed differentiation, epithelial-cells, expression, kidney engineering, kidney organoids, model, mouse, nephrogenesis, nephron number, podocytes, progenitor, Crispr, Kidney engineering, Kidney organoids, Nephrogenesis, Pluripotent stem cells, Pluripotent stem-cells
Arque, X, Patino, T, Sanchez, S, (2022). Enzyme-powered micro- and nano-motors: key parameters for an application-oriented design Chemical Science 13, 9128-9146
Nature has inspired the creation of artificial micro- and nanomotors that self-propel converting chemical energy into mechanical action. These tiny machines have appeared as promising biomedical tools for treatment and diagnosis and have also been used for environmental, antimicrobial or sensing applications. Among the possible catalytic engines, enzymes have emerged as an alternative to inorganic catalysts due to their biocompatibility and the variety and bioavailability of fuels. Although the field of enzyme-powered micro- and nano-motors has a trajectory of more than a decade, a comprehensive framework on how to rationally design, control and optimize their motion is still missing. With this purpose, herein we performed a thorough bibliographic study on the key parameters governing the propulsion of these enzyme-powered devices, namely the chassis shape, the material composition, the motor size, the enzyme type, the method used to incorporate enzymes, the distribution of the product released, the motion mechanism, the motion media and the technique used for motion detection. In conclusion, from the library of options that each parameter offers there needs to be a rational selection and intelligent design of enzymatic motors based on the specific application envisioned.
JTD Keywords: Catalase, Hydrogen-peroxide, Micro/nanomotors, Micromotors, Movement, Nanomotors, Propulsion, Surfactants, Therapy, Tumor microenvironment
Ordoño, J, Pérez-Amodio, S, Ball, K, Aguirre, A, Engel, E, (2022). The generation of a lactate-rich environment stimulates cell cycle progression and modulates gene expression on neonatal and hiPSC-derived cardiomyocytes BIOMATERIALS ADVANCES 139, 213035
In situ tissue engineering strategies are a promising approach to activate the endogenous regenerative potential of the cardiac tissue helping the heart to heal itself after an injury. However, the current use of complex reprogramming vectors for the activation of reparative pathways challenges the easy translation of these therapies into the clinic. Here, we evaluated the response of mouse neonatal and human induced pluripotent stem cell-derived cardiomyocytes to the presence of exogenous lactate, thus mimicking the metabolic environment of the fetal heart. An increase in cardiomyocyte cell cycle activity was observed in the presence of lactate, as determined through Ki67 and Aurora-B kinase. Gene expression and RNA-sequencing data revealed that cardiomyocytes incubated with lactate showed upregulation of BMP10, LIN28 or TCIM in tandem with downregulation of GRIK1 or DGKK among others. Lactate also demonstrated a capability to modulate the production of inflammatory cytokines on cardiac fibroblasts, reducing the production of Fas, Fraktalkine or IL-12p40, while stimulating IL-13 and SDF1a. In addition, the generation of a lactate-rich environment improved ex vivo neonatal heart culture, by affecting the contractile activity and sarcomeric structures and inhibiting epicardial cell spreading. Our results also suggested a common link between the effect of lactate and the activation of hypoxia signaling pathways. These findings support a novel use of lactate in cardiac tissue engineering, modulating the metabolic environment of the heart and thus paving the way to the development of lactate-releasing platforms for in situ cardiac regeneration.Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.
JTD Keywords: cardiac regeneration, cardiac tissue engineering, cell cycle, failure, growth, heart regeneration, induced pluripotent stem cells, ischemia, lactate, metabolic environment, metabolism, mouse, proliferation, repair, Bone morphogenetic protein-10, Cardiac tissue engineering, Cardiomyocytes, Cell cycle, Induced pluripotent stem cells, Lactate, Metabolic environment
Duch, P, Diaz-Valdivia, N, Ikemori, R, Gabasa, M, Radisky, ES, Arshakyan, M, Gea-Sorli, S, Mateu-Bosch, A, Bragado, P, Carrasco, JL, Mori, H, Ramirez, J, Teixido, C, Reguart, N, Fillat, C, Radisky, DC, Alcaraz, J, (2022). Aberrant TIMP-1 overexpression in tumor-associated fibroblasts drives tumor progression through CD63 in lung adenocarcinoma MATRIX BIOLOGY 111, 207-225
Tissue inhibitor of metalloproteinase-1 (TIMP-1) is an important regulator of extracellular matrix turnover that has been traditionally regarded as a potential tumor suppressor owing to its inhibitory effects of matrix metal-loproteinases. Intriguingly, this interpretation has been challenged by the consistent observation that increased expression of TIMP-1 is associated with poor prognosis in virtually all cancer types including lung cancer, supporting a tumor-promoting function. However, how TIMP-1 is dysregulated within the tumor micro-environment and how it drives tumor progression in lung cancer is poorly understood. We analyzed the expression of TIMP-1 and its cell surface receptor CD63 in two major lung cancer subtypes: lung adenocarci-noma (ADC) and squamous cell carcinoma (SCC), and defined the tumor-promoting effects of their interac-tion. We found that TIMP-1 is aberrantly overexpressed in tumor-associated fibroblasts (TAFs) in ADC compared to SCC. Mechanistically, TIMP-1 overexpression was mediated by the selective hyperactivity of the pro-fibrotic TGF-61/SMAD3 pathway in ADC-TAFs. Likewise, CD63 was upregulated in ADC compared to SCC cells. Genetic analyses revealed that TIMP-1 secreted by TGF-61-activated ADC-TAFs is both nec-essary and sufficient to enhance growth and invasion of ADC cancer cells in culture, and that tumor cell expression of CD63 was required for these effects. Consistently, in vivo analyses revealed that ADC cells co-injected with fibroblasts with reduced SMAD3 or TIMP-1 expression into immunocompromised mice attenu-ated tumor aggressiveness compared to tumors bearing parental fibroblasts. We also found that high TIMP1 and CD63 mRNA levels combined define a stronger prognostic biomarker than TIMP1 alone. Our results identify an excessive stromal TIMP-1 within the tumor microenvironment selectively in lung ADC, and implicate it in a novel tumor-promoting TAF-carcinoma crosstalk, thereby pointing to TIMP-1/CD63 interaction as a novel therapeutic target in lung cancer. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
JTD Keywords: cancer-associated fibroblast, cd63, fibrosis, smad3, tgf-β1, timp-1, Angiogenesis, Cancer cells, Cancer-associated fibroblast, Cd63, Expression, Fibrosis, Hepatocellular-carcinoma, Metalloproteinases, Nintedanib, Prognostic-significance, Protein, Smad3, Squamous-cell carcinoma, Tgf-? 1, Tgf-β1, Timp-1, Tissue inhibitor, Tumor microenvironment
Bernabeu, M, Aznar, S, Prieto, A, Huttener, M, Juarez, A, (2022). Differential Expression of Two Copies of the irmA Gene in the Enteroaggregative E. coli Strain 042 Microbiology Spectrum 10, e0045422
Gene duplications occur in prokaryotic genomes at a detectable frequency. In many instances, the biological function of the duplicates is unknown, and hence, the significance of the presence of multiple copies of these genes remains unclear.; Gene duplications significantly impact the gene repertoires of both eukaryotic and prokaryotic microorganisms. The genomes of pathogenic Escherichia coli strains share a group of duplicated genes whose function is mostly unknown. The irmA gene is one of the duplicates encoded in several pathogenic E. coli strains. The function of its gene product was investigated in the uropathogenic E. coli strain CFT073, which contains a single functional copy. The IrmA protein structure mimics that of human interleukin receptors and likely plays a role during infection. The enteroaggregative E. coli strain 042 contains two functional copies of the irmA gene. In the present work, we investigated their biological roles. The irmA_4509 allele is expressed under several growth conditions. Its expression is modulated by the global regulators OxyR and Hha, with optimal expression at 37 degrees C and under nutritional stress conditions. Expression of the irmA_2244 allele can only be detected when the irmA_4509 allele is knocked out. Differences in the promoter regions of both alleles account for their differential expression. Our results show that under several environmental conditions, the expression of the IrmA protein in strain 042 is dictated by the irmA_4509 allele. The irmA_2244 allele appears to play a backup role to ensure IrmA expression when the irmA_4509 allele loses its function. IMPORTANCE Gene duplications occur in prokaryotic genomes at a detectable frequency. In many instances, the biological function of the duplicates is unknown, and hence, the significance of the presence of multiple copies of these genes remains unclear. In pathogenic E. coli isolates, the irmA gene can be present either as a single copy or in two or more copies. We focused our work on studying why a different pathogenic E. coli strain encodes two functional copies of the irmA gene. We show that under several environmental conditions, one of the alleles dictates IrmA expression, and the second remains silent. The latter allele is only expressed when the former is silenced. The presence of more than one functional copy of the irmA gene in some pathogenic E. coli strains can result in sufficient expression of this virulence factor during the infection process.
JTD Keywords: 042, aec69, enteroaggregative e. coli, gene duplications, 042, Adaptation, Aec69, Aggregative adherence, Alleles, Chromosomal genes, Coli, Duplication, Enteroaggregative e, Enteroaggregative e. coli, Escherichia coli infections, Escherichia coli proteins, Escherichia-coli, Evolution, Gene duplications, Hha/ymoa, Humans, Irma, Mechanism, Outer-membrane, Protein, Uropathogenic escherichia coli
Amil, AF, Ballester, BR, Maier, M, Verschure, PFMJ, (2022). Chronic use of cannabis might impair sensory error processing in the cerebellum through endocannabinoid dysregulation ADDICTIVE BEHAVIORS 131, 107297
Chronic use of cannabis leads to both motor deficits and the downregulation of CB1 receptors (CB1R) in the cerebellum. In turn, cerebellar damage is often related to impairments in motor learning and control. Further, a recent motor learning task that measures cerebellar-dependent adaptation has been shown to distinguish well between healthy subjects and chronic cannabis users. Thus, the deteriorating effects of chronic cannabis use in motor performance point to cerebellar adaptation as a key process to explain such deficits. We review the literature relating chronic cannabis use, the endocannabinoid system in the cerebellum, and different forms of cerebellar-dependent motor learning, to suggest that CB1R downregulation leads to a generalized underestimation and misprocessing of the sensory errors driving synaptic updates in the cerebellar cortex. Further, we test our hypothesis with a computational model performing a motor adaptation task and reproduce the behavioral effect of decreased implicit adaptation that appears to be a sign of chronic cannabis use. Finally, we discuss the potential of our hypothesis to explain similar phenomena related to motor impairments following chronic alcohol dependency. © 2022
JTD Keywords: adaptation, addiction, alcohol-abuse, cerebellum, chronic cannabis use, cognition, deficits, endocannabinoid system, error processing, explicit, modulation, motor learning, release, synaptic plasticity, Adaptation, Adaptation, physiological, Alcoholism, Article, Behavioral science, Cannabinoid 1 receptor, Cannabis, Cannabis addiction, Cerebellum, Cerebellum cortex, Cerebellum disease, Chronic cannabis use, Computer model, Down regulation, Endocannabinoid, Endocannabinoid system, Endocannabinoids, Error processing, Hallucinogens, Human, Humans, Motor dysfunction, Motor learning, Nerve cell plasticity, Nonhuman, Physiology, Psychedelic agent, Purkinje-cells, Regulatory mechanism, Sensation, Sensory dysfunction, Sensory error processing impairment, Synaptic transmission, Task performance
Astro, V, Ramirez-Calderon, G, Pennucci, R, Caroli, J, Saera-Vila, A, Cardona-Londono, K, Forastieri, C, Fiacco, E, Maksoud, F, Alowaysi, M, Sogne, E, Falqui, A, Gonzalez, F, Montserrat, N, Battaglioli, E, Mattevi, A, Adamo, A, (2022). Fine-tuned KDM1A alternative splicing regulates human cardiomyogenesis through an enzymatic-independent mechanism iScience 25, 104665
The histone demethylase KDM1A is a multi- faceted regulator of vital developmental processes, including mesodermal and cardiac tube formation during gastrulation. However, it is unknown whether the fine-tuning of KDM1A splicing isoforms, already shown to regulate neuronal maturation, is crucial for the specification and maintenance of cell identity during cardiogenesis. Here, we discovered a temporal modulation of ubKDM1A and KDM1A+2a during human and mice fetal cardiac development and evaluated their impact on the regulation of cardiac differentiation. We revealed a severely impaired cardiac differentiation in KDM1A(-/-) hESCs that can be rescued by re-expressing ubKDM1A or catalytically impaired ubKDM1A-K661A, but not by KDM1A+2a or KDM1A+2a-K661A. Conversely, KDM1A+2a(-/-) hESCs give rise to functional cardiac cells, displaying increased beating amplitude and frequency and enhanced expression of critical cardiogenic markers. Our findings prove the existence of a divergent scaffolding role of KDM1A splice variants, independent of their enzymatic activity, during hESC differentiation into cardiac cells.
JTD Keywords: cell biology, molecular mechanism of gene regulation, omics, Bhlh transcription factor, Cell biology, Corest, Differentiation, Dna, Embryonic stem-cells, Heart, Lsd1, Molecular mechanism of gene regulation, Omics, Phosphorylation, Proteins, Stem cells research, Swirm domain
Riera, R, Tauler, J, Feiner-Gracia, N, Borrós, S, Fornaguera, C, Albertazzi, L, (2022). Complex pBAE Nanoparticle Cell Trafficking: Tracking Both Position and Composition Using Super Resolution Microscopy ChemMedChem 17, e202100633
Nanomedicine emerged some decades ago with the hope to be the solution for most unmet medical needs. However, tracking materials at nanoscale is challenging to their reduced size, below the resolution limit of most conventional techniques. In this context, we propose the use of direct stochastic optical reconstruction microscopy (dSTORM) to study time stability and cell trafficking after transfection of oligopeptide end-modified poly(?-aminoester) (OM-pBAE) nanoparticles. We selected different combinations of cationic end oligopeptides (arginine - R; histidine - H; and lysine - K) among polymer libraries, since the oligopeptide combination demonstrated to be useful for different applications, such as vaccination and gene silencing. We demonstrate that their time evolution as well as their cell uptake and trafficking are dependent on the oligopeptide. This study opens the pave to broad mechanistic studies at nanoscale that could enable a rational selection of specific pBAE nanoparticles composition after determining their stability and cell trafficking.© 2022 The Authors. ChemMedChem published by Wiley-VCH GmbH.
JTD Keywords: cancer nanomedicine, cell trafficking, delivery, direct stochastic optical reconstruction microscopy (dstorm), nanoparticle stability, poly(beta-aminoester) nanoparticles, Direct stochastic optical reconstruction microscopy (dstorm), Poly(?-aminoester) nanoparticles, Poly(beta-amino ester)s, Poly(β-aminoester) nanoparticles
Verschure, PFMJ, Wierenga, S, (2022). Future memory: a digital humanities approach for the preservation and presentation of the history of the Holocaust and Nazi crimes Holocaust Studies 28, 331-357
We describe the concepts, methodology, technology, and practice of a user-centric and historical space-oriented approach towards Historical and Cultural Learning (HCL). The Future Memory project pursues the unifying hypothesis that physical space can play a critical role in the authentication and education of this singular historical event, or space as a frame for memory formation and a source of authentication. We illustrate these aspects in the context of concrete Future Memory projects realized over the last ten years in collaboration with several memorial sites, museums, and archives. Based on these experiences, we subsequently analyze the lessons learned and future challenges.
JTD Keywords: Augmented reality, Behavior, Commemoration, Design, Digital heritage, Experience, Framework, Future memory, Mobile, Navigation, Place cells, Post-wtiness era, Space, Virtual reality
Castagna, R, Kolarski, D, Durand-de Cuttoli, R, Maleeva, G, (2022). Orthogonal Control of Neuronal Circuits and Behavior Using Photopharmacology JOURNAL OF MOLECULAR NEUROSCIENCE 72, 1433-1442
Over the last decades, photopharmacology has gone far beyond its proof-of-concept stage to become a bona fide approach to study neural systems in vivo. Indeed, photopharmacological control has expanded over a wide range of endogenous targets, such as receptors, ion channels, transporters, kinases, lipids, and DNA transcription processes. In this review, we provide an overview of the recent progresses in the in vivo photopharmacological control of neuronal circuits and behavior. In particular, the use of small aquatic animals for the in vivo screening of photopharmacological compounds, the recent advances in optical modulation of complex behaviors in mice, and the development of adjacent techniques for light and drug delivery in vivo are described.
JTD Keywords: brain circuits, circadian rhythm, in vivo photomodulation, in vivo technology, neuronal receptors, Architecture, Azobenzene photoswitches, Brain circuits, Channels, Circadian rhythm, In vivo photomodulation, In vivo technology, Light, Modulator, Neuronal receptors, Optical control, Optogenetics, Pharmacology, Photopharmacology, Receptors, Systems
Lozano-Garcia, M, Estrada-Petrocelli, L, Blanco-Almazan, D, Tas, B, Cho, PSP, Moxham, J, Rafferty, GF, Torres, A, Jane, R, Jolley, CJ, (2022). Noninvasive Assessment of Neuromechanical and Neuroventilatory Coupling in COPD IEEE Journal of Biomedical and Health Informatics 26, 3385-3396
This study explored the use of parasternal second intercostal space and lower intercostal space surface electromyogram (sEMG) and surface mechanomyogram (sMMG) recordings (sEMGpara and sMMGpara, and sEMGlic and sMMGlic, respectively) to assess neural respiratory drive (NRD), neuromechanical (NMC) and neuroventilatory (NVC) coupling, and mechanical efficiency (MEff) noninvasively in healthy subjects and chronic obstructive pulmonary disease (COPD) patients. sEMGpara, sMMGpara, sEMGlic, sMMGlic, mouth pressure (Pmo), and volume (Vi) were measured at rest, and during an inspiratory loading protocol, in 16 COPD patients (8 moderate and 8 severe) and 9 healthy subjects. Myographic signals were analyzed using fixed sample entropy and normalized to their largest values (fSEsEMGpara%max, fSEsMMGpara%max, fSEsEMGlic%max, and fSEsMMGlic%max). fSEsMMGpara%max, fSEsEMGpara%max, and fSEsEMGlic%max were significantly higher in COPD than in healthy participants at rest. Parasternal intercostal muscle NMC was significantly higher in healthy than in COPD participants at rest, but not during threshold loading. Pmo-derived NMC and MEff ratios were lower in severe patients than in mild patients or healthy subjects during threshold loading, but differences were not consistently significant. During resting breathing and threshold loading, Vi-derived NVC and MEff ratios were significantly lower in severe patients than in mild patients or healthy subjects. sMMG is a potential noninvasive alternative to sEMG for assessing NRD in COPD. The ratios of Pmo and Vi to sMMG and sEMG measurements provide wholly noninvasive NMC, NVC, and MEff indices that are sensitive to impaired respiratory mechanics in COPD and are therefore of potential value to assess disease severity in clinical practice. Author
JTD Keywords: biomedical measurement, chronic obstructive pulmonary disease, couplings, diaphragm, disease severity, efficiency, electromyography, exacerbations, healthy volunteers, inspiratory muscles, loading, mechanomyography, obstructive pulmonary-disease, pressure measurement, protocols, respiratory mechanics, respiratory muscles, responsiveness, spirometry, stimulation, volume measurement, At rests, Biomedical measurement, Biomedical measurements, Chronic obstructive pulmonary disease, Couplings, Disease severity, Efficiency ratio, Electromyography, Healthy subjects, Healthy volunteers, Loading, Mechanical efficiency, Mechanomyogram, Muscle, Muscles, Neural respiratory drive, Noninvasive medical procedures, Pressure measurement, Protocols, Pulmonary diseases, Surface electromyogram, Volume measurement
Mura, A, Maier, M, Ballester, BR, Costa, JD, Lopez-Luque, J, Gelineau, A, Mandigout, S, Ghatan, PH, Fiorillo, R, Antenucci, F, Coolen, T, Chivite, I, Callen, A, Landais, H, Gomez, OI, Melero, C, Brandi, S, Domenech, M, Daviet, JC, Zucca, R, Verschure, PFMJ, (2022). Bringing rehabilitation home with an e-health platform to treat stroke patients: study protocol of a randomized clinical trial (RGS@home) Trials 23, 518
Background: There is a pressing need for scalable healthcare solutions and a shift in the rehabilitation paradigm from hospitals to homes to tackle the increase in stroke incidence while reducing the practical and economic burden for patients, hospitals, and society. Digital health technologies can contribute to addressing this challenge; however, little is known about their effectiveness in at-home settings. In response, we have designed the RGS@home study to investigate the effectiveness, acceptance, and cost of a deep tech solution called the Rehabilitation Gaming System (RGS). RGS is a cloud-based system for delivering Al-enhanced rehabilitation using virtual reality, motion capture, and wearables that can be used in the hospital and at home. The core principles of the brain theory-based RGS intervention are to deliver rehabilitation exercises in the form of embodied, goal-oriented, and task-specific action.; Methods: The RGS@home study is a randomized longitudinal clinical trial designed to assess whether the combination of the RGS intervention with standard care is superior to standard care alone for the functional recovery of stroke patients at the hospital and at home. The study is conducted in collaboration with hospitals in Spain, Sweden, and France and includes inpatients and outpatients at subacute and chronic stages post-stroke. The intervention duration is 3 months with assessment at baseline and after 3, 6, and 12 months. The impact of RGS is evaluated in terms of quality of life measurements, usability, and acceptance using standardized clinical scales, together with health economic analysis. So far, one-third of the patients expected to participate in the study have been recruited (N = 90, mean age 60, days after stroke >= 30 days). The trial will end in July 2023.; Discussion: We predict an improvement in the patients' recovery, high acceptance, and reduced costs due to a soft landing from the clinic to home rehabilitation. In addition, the data provided will allow us to assess whether the prescription of therapy at home can counteract deterioration and improve quality of life while also identifying new standards for online and remote assessment, diagnostics, and intervention across European hospitals.
JTD Keywords: deep tech, e-health, home treatment, motor recovery, randomized clinical trial, stroke, upper extremities, virtual reality, Deep tech, E-health, Functional recovery, Home treatment, Humans, Middle aged, Motor recovery, Quality of life, Randomized clinical trial, Randomized controlled trials as topic, Recovery of function, Stroke, Stroke rehabilitation, Telemedicine, Upper extremities, Virtual reality, Wearables
Garreta, E, Prado, P, Stanifer, ML, Monteil, V, Marco, A, Ullate-Agote, A, Moya-Rull, D, Vilas-Zornoza, A, Tarantino, C, Romero, JP, Jonsson, G, Oria, R, Leopoldi, A, Hagelkruys, A, Gallo, M, González, F, Domingo-Pedrol, P, Gavaldà, A, del Pozo, CH, Ali, OH, Ventura-Aguiar, P, Campistol, JM, Prosper, F, Mirazimi, A, Boulant, S, Penninger, JM, Montserrat, N, (2022). A diabetic milieu increases ACE2 expression and cellular susceptibility to SARS-CoV-2 infections in human kidney organoids and patient cells Cell Metabolism 34, 857-873
It is not well understood why diabetic individuals are more prone to develop severe COVID-19. To this, we here established a human kidney organoid model promoting early hallmarks of diabetic kidney disease development. Upon SARS-CoV-2 infection, diabetic-like kidney organoids exhibited higher viral loads compared with their control counterparts. Genetic deletion of the angiotensin-converting enzyme 2 (ACE2) in kidney organoids under control or diabetic-like conditions prevented viral detection. Moreover, cells isolated from kidney biopsies from diabetic patients exhibited altered mitochondrial respiration and enhanced glycolysis, resulting in higher SARS-CoV-2 infections compared with non-diabetic cells. Conversely, the exposure of patient cells to dichloroacetate (DCA), an inhibitor of aerobic glycolysis, resulted in reduced SARS-CoV-2 infections. Our results provide insights into the identification of diabetic-induced metabolic programming in the kidney as a critical event increasing SARS-CoV-2 infection susceptibility, opening the door to the identification of new interventions in COVID-19 pathogenesis targeting energy metabolism.Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.
JTD Keywords: complications, coronavirus, cultured-cells, disease, distal tubule, mouse, protein, reveals, spike, Ace2, Ace2 protein, human, Angiotensin-converting enzyme 2, Angiotensin-converting enzyme-2, Covid-19, Diabetes 2, Diabetes mellitus, Diabetic nephropathies, Human kidney organoids, Humans, Kidney, Organoids, Peptidyl-dipeptidase a, Sars-cov-2
English, C, Ceravolo, MG, Dorsch, S, Drummond, A, Gandhi, DBC, Green, JH, Schelfaut, B, Verschure, P, Urimubenshi, G, Savitz, S, (2022). Telehealth for rehabilitation and recovery after stroke: State of the evidence and future directions International Journal of Stroke 17, 487-493
Aims: The aim of this rapid review and opinion paper is to present the state of the current evidence and present future directions for telehealth research and clinical service delivery for stroke rehabilitation. Methods: We conducted a rapid review of published trials in the field. We searched Medline using key terms related to stroke rehabilitation and telehealth or virtual care. We also searched clinical trial registers to identify key ongoing trials. Results: The evidence for telehealth to deliver stroke rehabilitation interventions is not strong and is predominantly based on small trials prone to Type 2 error. To move the field forward, we need to progress to trials of implementation that include measures of adoption and reach, as well as effectiveness. We also need to understand which outcome measures can be reliably measured remotely, and/or develop new ones. We present tools to assist with the deployment of telehealth for rehabilitation after stroke. Conclusion: The current, and likely long-term, pandemic means that we cannot wait for stronger evidence before implementing telehealth. As a research and clinical community, we owe it to people living with stroke internationally to investigate the best possible telehealth solutions for providing the highest quality rehabilitation.
JTD Keywords: rehabilitation, telehealth, Care, Feasibility, Rehabilitation, Telehealth, Trial, Virtual care
Batlle, D, Monteil, V, Garreta, E, Hassler, L, Wysocki, J, Chandar, V, Schwartz, RE, Mirazimi, A, Montserrat, N, Bader, M, Penninger, JM, (2022). Evidence in favor of the essentiality of human cell membrane-bound ACE2 and against soluble ACE2 for SARS-CoV-2 infectivity CELL 185, 1837-1839
Ferrer, I, Andrés-Benito, P, Garcia-Esparcia, P, López-Gonzalez, I, Valiente, D, Jordán-Pirla, M, Carmona, M, Sala-Jarque, J, Gil, V, del Rio, JA, (2022). Differences in Tau Seeding in Newborn and Adult Wild-Type Mice INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 23, 4789
Alzheimer’s disease (AD) and other tauopathies are common neurodegenerative diseases in older adults; in contrast, abnormal tau deposition in neurons and glial cells occurs only exceptionally in children. Sarkosyl-insoluble fractions from sporadic AD (sAD) containing paired helical filaments (PHFs) were inoculated unilaterally into the thalamus in newborn and three-month-old wild-type C57BL/6 mice, which were killed at different intervals from 24 h to six months after inoculation. Tau-positive cells were scanty and practically disappeared at three months in mice inoculated at the age of a newborn. In contrast, large numbers of tau-positive cells, including neurons and oligodendrocytes, were found in the thalamus of mice inoculated at three months and killed at the ages of six months and nine months. Mice inoculated at the age of newborn and re-inoculated at the age of three months showed similar numbers and distribution of positive cells in the thalamus at six months and nine months. This study shows that (a) differences in tau seeding between newborn and young adults may be related to the ratios between 3Rtau and 4Rtau, and the shift to 4Rtau predominance in adults, together with the immaturity of connections in newborn mice, and (b) intracerebral inoculation of sAD PHFs in newborn mice does not protect from tau seeding following intracerebral inoculation of sAD PHFs in young/adult mice.
JTD Keywords: alzheimer's disease, alzheimer-disease, alzheimer’s disease, expression, mouse tau, neurofibrillary tangles, newborn, pathological tau, propagation, protein-tau, spread, tau seeding and spreading, thalamus, transgenic mice, Alzheimer disease, Alzheimer’s disease, Animals, Brain, Mice, Mice, inbred c57bl, Mice, transgenic, Neurofibrillary tangles, Newborn, Paired helical filaments, Tau proteins, Tau seeding and spreading, Tauopathies, Thalamus
De Chiara, F, Ferret-Miñana, A, Fernández-Costa, JM, Senni, A, Jalan, R, Ramón-Azcón, J, (2022). Fatty Hepatocytes Induce Skeletal Muscle Atrophy In Vitro: A New 3D Platform to Study the Protective Effect of Albumin in Non-Alcoholic Fatty Liver Biomedicines 10, 958
The liver neutralizes endogenous and exogenous toxins and metabolites, being metabolically interconnected with many organs. Numerous clinical and experimental studies show a strong association between Non-alcoholic fatty liver disease (NAFLD) and loss of skeletal muscle mass known as sarcopenia. Liver transplantation solves the hepatic-related insufficiencies, but it is unable to revert sarcopenia. Knowing the mechanism(s) by which different organs communicate with each other is crucial to improve the drug development that still relies on the two-dimensional models. However, those models fail to mimic the pathological features of the disease. Here, both liver and skeletal muscle cells were encapsulated in gelatin methacryloyl and carboxymethylcellulose to recreate the disease’s phenotype in vitro. The 3D hepatocytes were challenged with non-esterified fatty acids (NEFAs) inducing features of Non-alcoholic fatty liver (NAFL) such as lipid accumulation, metabolic activity impairment and apoptosis. The 3D skeletal muscle tissues incubated with supernatant from fatty hepatocytes displayed loss of maturation and atrophy. This study demonstrates the connection between the liver and the skeletal muscle in NAFL, narrowing down the players for potential treatments. The tool herein presented was employed as a customizable 3D in vitro platform to assess the protective effect of albumin on both hepatocytes and myotubes.
JTD Keywords: 3r, ammonia, cirrhosis, crosstalk, disease, expression, myostatin, nefas, sarcopenia, tissue engineering, 3r, Ammonia, Crosstalk, Nefas, Nuclear factor 4-alpha, Tissue engineering
Marti, D, Martin-Martinez, E, Torras, J, Betran, O, Turon, P, Aleman, C, (2022). In silico study of substrate chemistry effect on the tethering of engineered antibodies for SARS-CoV-2 detection: Amorphous silica vs gold COLLOIDS AND SURFACES B-BIOINTERFACES 213, 112400
The influence of the properties of different solid substrates on the tethering of two antibodies, IgG1-CR3022 and IgG1-S309, which were specifically engineered for the detection of SARS-CoV-2, has been examined at the molecular level using conventional and accelerated Molecular Dynamics (cMD and aMD, respectively). Two surfaces with very different properties and widely used in immunosensors for diagnosis, amorphous silica and the most stable facet of the face-centered cubic gold structure, have been considered. The effects of such surfaces on the structure and orientation of the immobilized antibodies have been determined by quantifying the tilt and hinge angles that describe the orientation and shape of the antibody, respectively, and the dihedrals that measure the relative position of the antibody arms with respect to the surface. Results show that the interactions with amorphous silica, which are mainly electrostatic due to the charged nature of the surface, help to preserve the orientation and structure of the antibodies, especially of the IgG1-CR3022, indicating that the primary sequence of those antibodies also plays some role. Instead, short-range van der Waals interactions with the inert gold surface cause a higher degree tilting and fraying of the antibodies with respect to amorphous silica. The interactions between the antibodies and the surface also affect the correlation among the different angles and dihedrals, which increases with their strength. Overall, results explain why amorphous silica substrates are frequently used to immobilize antibodies in immunosensors. © 2022 The Authors
JTD Keywords: amorphous silica, antibody immobilization, enzyme, gol d, gold, immobilization, immunosensor, molecu l a r dynamics, molecular dynamics, protein adsorption, sars-cov-2 immunosensor, simulations, spike protein, surface interactions, target, vaccine, Amorphous silica, Antibodies, Antibody engineering, Antibody immobilization, Antibody structure, Article, Chemical detection, Computer model, Controlled study, Dihedral angle, Gold, In-silico, Molecular dynamics, Molecular levels, Molecular-dynamics, Nonhuman, Property, Sars, Sars-cov-2 immunosensor, Severe acute respiratory syndrome coronavirus 2, Silica, Silico studies, Silicon dioxide, Solid substrates, Structure analysis, Substrate chemistry, Substrates, Van der waals forces, Virus detection
Tas, B, Kalk, NJ, Lozano-García, M, Rafferty, GF, Cho, PSP, Kelleher, M, Moxham, J, Strang, J, Jolley, CJ, (2022). Undetected Respiratory Depression in People with Opioid Use Disorder DRUG AND ALCOHOL DEPENDENCE 234, 109401
Background: Opioid-related deaths are increasing globally. Respiratory complications of opioid use and underlying respiratory disease in people with Opioid Use Disorder (OUD) are potential contributory factors. Individual variation in susceptibility to overdose is, however, incompletely understood. This study investigated the prevalence of respiratory depression (RD) in OUD treatment and compared this to patients with chronic obstructive pulmonary disease (COPD) of equivalent severity. We also explored the contribution of opioid agonist treatment (OAT) dosage, and type, to the prevalence of RD. Methods: There were four groups of participants: 1) OUD plus COPD (‘OUD-COPD’, n = 13); 2) OUD without COPD (‘OUD’, n = 7); 3) opioid-naïve COPD patients (‘COPD'n = 13); 4) healthy controls (‘HC'n = 7). Physiological indices, including pulse oximetry (SpO2%), end-tidal CO2 (ETCO2), transcutaneous CO2 (TcCO2), respiratory airflow and second intercostal space parasternal muscle electromyography (EMGpara), were recorded continuously over 40 min whilst awake at rest. Significant RD was defined as: SpO2%< 90% for > 10 s, ETCO2 per breath > 6.6 kPa, TcCO2 overall mean > 6 kPa, respiratory pauses > 10 s Results: At least one indicator was observed in every participant with OUD (n = 20). This compared to RD episode occurrence in only 2/7 HC and 2/13 COPD participants (p < 0.05,Fisher's exact test). The occurrence of RD was similar in OUD participants prescribed methadone (n = 6) compared to those prescribed buprenorphine (n = 12). Conclusions: Undetected RD is common in OUD cohorts receiving OAT and is significantly more severe than in opioid-naïve controls. RD can be assessed using simple objective measures. Further studies are required to determine the association between RD and overdose risk. © 2022 Elsevier B.V.
JTD Keywords: buprenorphine, comorbidity, deaths, drive, heroin, lung disease, opioid substitution treatment, opioids, overdose, pulse oximetry, respiratory depression, risk, Acute exacerbations, Comorbidity, Lung disease, Opioid substitution treatment, Opioids, Overdose, Respiratory depression
Schieber, R, Mas-Moruno, C, Lasserre, F, Roa, JJ, Ginebra, MP, Mücklich, F, Pegueroles, M, (2022). Effectiveness of Direct Laser Interference Patterning and Peptide Immobilization on Endothelial Cell Migration for Cardio-Vascular Applications: An In Vitro Study Nanomaterials 12, 1217
Endothelial coverage of an exposed cardiovascular stent surface leads to the occurrence of restenosis and late-stent thrombosis several months after implantation. To overcome this difficulty, modification of stent surfaces with topographical or biochemical features may be performed to increase endothelial cells’ (ECs) adhesion and/or migration. This work combines both strategies on cobalt-chromium (CoCr) alloy and studies the potential synergistic effect of linear patterned surfaces that are obtained by direct laser interference patterning (DLIP), coupled with the use of Arg-Gly-Asp (RGD) and Tyr-Ile-Gly-Ser-Arg (YIGSR) peptides. An extensive characterization of the modified surfaces was performed by using AFM, XPS, surface charge, electrochemical analysis and fluorescent methods. The biological response was studied in terms of EC adhesion, migration and proliferation assays. CoCr surfaces were successfully patterned with a periodicity of 10 µm and two different depths, D (≈79 and 762 nm). RGD and YIGSR were immobilized on the surfaces by CPTES silanization. Early EC adhesion was increased on the peptide-functionalized surfaces, especially for YIGSR compared to RGD. High-depth patterns generated 80% of ECs’ alignment within the topographical lines and enhanced EC migration. It is noteworthy that the combined use of the two strategies synergistically accelerated the ECs’ migration and proliferation, proving the potential of this strategy to enhance stent endothelialization.
JTD Keywords: adhesion, bare-metal, biofunctionalization, biomaterials, cell adhesive peptides, cobalt-chromium alloy, direct laser interference patterning (dlip), endothelial cell migration, functionalization, matrix, proliferation, selectivity, shear-stress, surfaces, Biofunctionalization, Cell adhesive peptides, Cobalt-chromium alloy, Direct laser interference patterning (dlip), Drug-eluting stents, Endothelial cell migration
Pavlova, EL, Semenov, RV, Pavlova-Deb, MP, Guekht, AB, (2022). Transcranial direct current stimulation of the premotor cortex aimed to improve hand motor function in chronic stroke patients BRAIN RESEARCH 1780, 147790
Objective: To investigate the effects of single-session premotor and primary motor tDCS in chronic stroke patients with relation to possible inter-hemispheric interactions. Methods: Anodal tDCS of either M1 or premotor cortex of the side contralateral to the paretic hand, cathodal tDCS of the premotor cortex of the side ipsilateral to the paretic hand and sham stimulation were performed in 12 chronic stroke patients with mild hand paresis in a balanced cross-over design. The Jebsen-Taylor Hand Function test, evaluating the time required for performance of everyday motor tasks, was employed. Results: The repeated-measure ANOVA with Greenhouse-Geisser correction showed significant influence of the stimulation type (factor SESSION; F(2.6, 28.4) = 47.3, p < 0.001), the test performance time relative to stimulation (during or after tDCS; factor TIME, F(1.0, 11.0) = 234.5, p < 0.001) with higher effect after the stimulation and the interaction SESSION*TIME (F(1.7, 1.2) = 30.5, p < 0.001). All active conditions were effective for the modulation of JTT performance, though the highest effect was observed after anodal tDCS of M1, followed by effects after anodal stimulation of the premotor cortex contralateral to the paretic hand. Based on the correlation patterns, the inhibitory input to M1 from premotor cortex of another hemisphere and an excitatory input from the ipsilesional premotor cortex were suggested. Conclusion: The premotor cortex is a promising candidate area for transcranial non-invasive stimulation of chronic stroke patients. © 2022 The Author(s)
JTD Keywords: areas, contralateral primary motor, dorsal premotor, excitability, jtt, lateral premotor, object manipulation, premotor cortex, recovery, stroke, tdcs, time-course, transcranial direct current stimulation, Jtt, Noninvasive brain-stimulation, Premotor cortex, Stroke, Tdcs, Transcranial direct current stimulation
Ballester, BR, Winstein, C, Schweighofer, N, (2022). Virtuous and Vicious Cycles of Arm Use and Function Post-stroke Frontiers in Neurology 13, 804211
Large doses of movement practice have been shown to restore upper extremities' motor function in a significant subset of individuals post-stroke. However, such large doses are both difficult to implement in the clinic and highly inefficient. In addition, an important reduction in upper extremity function and use is commonly seen following rehabilitation-induced gains, resulting in “rehabilitation in vain”. For those with mild to moderate sensorimotor impairment, the limited spontaneous use of the more affected limb during activities of daily living has been previously proposed to cause a decline of motor function, initiating a vicious cycle of recovery, in which non-use and poor performance reinforce each other. Here, we review computational, experimental, and clinical studies that support the view that if arm use is raised above an effective threshold, one enters a virtuous cycle in which arm use and function can reinforce each other via self-practice in the wild. If not, one enters a vicious cycle of declining arm use and function. In turn, and in line with best practice therapy recommendations, this virtuous/vicious cycle model advocates for a paradigm shift in neurorehabilitation whereby rehabilitation be embedded in activities of daily living such that self-practice with the aid of wearable technology that reminds and motivates can enhance paretic limb use of those who possess adequate residual sensorimotor capacity. Altogether, this model points to a user-centered approach to recovery post-stroke that is tailored to the participant's level of arm use and designed to motivate and engage in self-practice through progressive success in accomplishing meaningful activities in the wild. Copyright © 2022 Ballester, Winstein and Schweighofer.
JTD Keywords: compensatory movement, computational neurorehabilitation, decision-making, individuals, learned non-use, learned nonuse, monkeys, neurorehabilitation, recovery, rehabilitation, stroke, stroke patients, wearable sensors, wrist, Arm movement, Article, Cerebrovascular accident, Clinical decision making, Clinical practice, Clinical study, Compensatory movement, Computational neurorehabilitation, Computer model, Daily life activity, Decision-making, Experimental study, Human, Induced movement therapy, Learned non-use, Musculoskeletal function, Neurorehabilitation, Paresis, Sensorimotor function, Stroke, Stroke rehabilitation, User-centered design, Vicious cycle, Virtuous cycle, Wearable sensors
Woythe, L, Madhikar, P, Feiner-Gracia, N, Storm, C, Albertazzi, L, (2022). A Single-Molecule View at Nanoparticle Targeting Selectivity: Correlating Ligand Functionality and Cell Receptor Density ACS Nano 16, 3785-3796
Antibody-functionalized nanoparticles (NPs) are commonly used to increase the targeting selectivity toward cells of interest. At a molecular level, the number of functional antibodies on the NP surface and the density of receptors on the target cell determine the targeting interaction. To rationally develop selective NPs, the single-molecule quantitation of both parameters is highly desirable. However, techniques able to count molecules with a nanometric resolution are scarce. Here, we developed a labeling approach to quantify the number of functional cetuximabs conjugated to NPs and the expression of epidermal growth factor receptors (EGFRs) in breast cancer cells using direct stochastic optical reconstruction microscopy (dSTORM). The single-molecule resolution of dSTORM allows quantifying molecules at the nanoscale, giving a detailed insight into the distributions of individual NP ligands and cell receptors. Additionally, we predicted the fraction of accessible antibody-conjugated NPs using a geometrical model, showing that the total number exceeds the accessible number of antibodies. Finally, we correlated the NP functionality, cell receptor density, and NP uptake to identify the highest cell uptake selectivity regimes. We conclude that single-molecule functionality mapping using dSTORM provides a molecular understanding of NP targeting, aiding the rational design of selective nanomedicines.
JTD Keywords: active targeting, active targeting dstorm, antibodies, dstorm, heterogeneity, multivalency, nanomedicine, nanoparticle functionality, size, super-resolution microscopy, surface, Active targeting, Antibodies, Cell membranes, Cell receptors, Cytology, Direct stochastic optical reconstruction microscopy, Dstorm, Heterogeneity, Ligands, Medical nanotechnology, Molecules, Nanomedicine, Nanoparticle functionality, Nanoparticle targeting, Nanoparticles, Optical reconstruction, Single molecule, Stochastic systems, Stochastics, Super-resolution microscopy, Superresolution microscopy
Bonilla-Pons, SA, Nakagawa, S, Bahima, EG, Fernández-Blanco, A, Pesaresi, M, D'Antin, JC, Sebastian-Perez, R, Greco, D, Domínguez-Sala, E, Gómez-Riera, R, Compte, RIB, Dierssen, M, Pulido, NM, Cosma, MP, (2022). Müller glia fused with adult stem cells undergo neural differentiation in human retinal models EBioMedicine 77, 103914
Visual impairments are a critical medical hurdle to be addressed in modern society. Müller glia (MG) have regenerative potential in the retina in lower vertebrates, but not in mammals. However, in mice, in vivo cell fusion between MG and adult stem cells forms hybrids that can partially regenerate ablated neurons.We used organotypic cultures of human retina and preparations of dissociated cells to test the hypothesis that cell fusion between human MG and adult stem cells can induce neuronal regeneration in human systems. Moreover, we established a microinjection system for transplanting human retinal organoids to demonstrate hybrid differentiation.We first found that cell fusion occurs between MG and adult stem cells, in organotypic cultures of human retina as well as in cell cultures. Next, we showed that the resulting hybrids can differentiate and acquire a proto-neural electrophysiology profile when the Wnt/beta-catenin pathway is activated in the adult stem cells prior fusion. Finally, we demonstrated the engraftment and differentiation of these hybrids into human retinal organoids.We show fusion between human MG and adult stem cells, and demonstrate that the resulting hybrid cells can differentiate towards neural fate in human model systems. Our results suggest that cell fusion-mediated therapy is a potential regenerative approach for treating human retinal dystrophies.This work was supported by La Caixa Health (HR17-00231), Velux Stiftung (976a) and the Ministerio de Ciencia e Innovación, (BFU2017-86760-P) (AEI/FEDER, UE), AGAUR (2017 SGR 689, 2017 SGR 926).Published by Elsevier B.V.
JTD Keywords: cell fusion, expression, fusion, ganglion-cells, in-vitro, mouse, müller glia, neural differentiation, organoids, regeneration, retina regeneration, stem cells, stromal cells, transplantation, 4',6 diamidino 2 phenylindole, 5' nucleotidase, Agarose, Alcohol, Arpe-19 cell line, Article, Beta catenin, Beta tubulin, Bone-marrow-cells, Bromophenol blue, Buffer, Calcium cell level, Calcium phosphate, Calretinin, Canonical wnt signaling, Cd34 antigen, Cell culture, Cell fusion, Cell viability, Coculture, Complementary dna, Confocal microscopy, Cornea transplantation, Cryopreservation, Cryoprotection, Crystal structure, Current clamp technique, Dimethyl sulfoxide, Dodecyl sulfate sodium, Edetic acid, Electrophysiology, Endoglin, Fetal bovine serum, Fibroblast growth factor 2, Flow cytometry, Fluorescence activated cell sorting, Fluorescence intensity, Glyceraldehyde 3 phosphate dehydrogenase, Glycerol, Glycine, Hoe 33342, Immunofluorescence, Immunohistochemistry, Incubation time, Interleukin 1beta, Lentivirus vector, Matrigel, Mercaptoethanol, Microinjection, Mueller cell, Müller glia, N methyl dextro aspartic acid, Nerve cell differentiation, Neural differentiation, Nitrogen, Nonhuman, Organoids, Paraffin, Paraffin embedding, Paraformaldehyde, Patch clamp technique, Penicillin derivative, Phenolsulfonphthalein, Phenotype, Phosphate buffered saline, Phosphoprotein phosphatase inhibitor, Polyacrylamide gel electrophoresis, Potassium chloride, Povidone iodine, Promoter region, Proteinase inhibitor, Real time polymerase chain reaction, Receptor type tyrosine protein phosphatase c, Restriction endonuclease, Retina, Retina dystrophy, Retina regeneration, Retinol, Rhodopsin, Rna extraction, Stem cell, Stem cells, Subcutaneous fat, Tunel assay, Visual impairment, Western blotting
Aydin, O, Passaro, AP, Raman, R, Spellicy, SE, Weinberg, RP, Kamm, RD, Sample, M, Truskey, GA, Zartman, J, Dar, RD, Palacios, S, Wang, J, Tordoff, J, Montserrat, N, Bashir, R, Saif, MTA, Weiss, R, (2022). Principles for the design of multicellular engineered living systems APL BIOENGINEERING 6, 10903
Remarkable progress in bioengineering over the past two decades has enabled the formulation of fundamental design principles for a variety of medical and non-medical applications. These advancements have laid the foundation for building multicellular engineered living systems (M-CELS) from biological parts, forming functional modules integrated into living machines. These cognizant design principles for living systems encompass novel genetic circuit manipulation, self-assembly, cell–cell/matrix communication, and artificial tissues/organs enabled through systems biology, bioinformatics, computational biology, genetic engineering, and microfluidics. Here, we introduce design principles and a blueprint for forward production of robust and standardized M-CELS, which may undergo variable reiterations through the classic design-build-test-debug cycle. This Review provides practical and theoretical frameworks to forward-design, control, and optimize novel M-CELS. Potential applications include biopharmaceuticals, bioreactor factories, biofuels, environmental bioremediation, cellular computing, biohybrid digital technology, and experimental investigations into mechanisms of multicellular organisms normally hidden inside the “black box” of living cells.
JTD Keywords: cell-fate specification, endothelial-cells, escherichia-coli, extracellular-matrix, gene-expression noise, nuclear hormone-receptors, pluripotent stem-cells, primitive endoderm, transcription factors, Artificial tissues, Assembly cells, Biological parts, Biological systems, Bioremediation, Blood-brain-barrier, Cell engineering, Cell/matrix communication, Design principles, Environmental technology, Functional modules, Fundamental design, Genetic circuits, Genetic engineering, Living machines, Living systems, Medical applications, Molecular biology, Synthetic biology
Tantai, X, Liu, Y, Yeo, YH, Praktiknjo, M, Mauro, E, Hamaguchi, Y, Engelmann, C, Zhang, P, Jeong, JY, van Vugt, JLA, Xiao, HJ, Deng, H, Gao, X, Ye, Q, Zhang, JY, Yang, LB, Cai, YQ, Liu, YX, Liu, N, Li, ZF, Han, T, Kaido, T, Sohn, JH, Strassburg, C, Berg, T, Trebicka, J, Hsu, YC, Ijzermans, JNM, Wang, JH, Su, GL, Ji, FP, Nguyen, MH, (2022). Effect of sarcopenia on survival of patients with cirrhosis: A meta-analysis JOURNAL OF HEPATOLOGY 76, 588-599
The association between sarcopenia and prognosis in patients with cirrhosis remains to be determined. In this study, we aimed to quantify the association between sarcopenia and the risk of mortality in patients with cirrhosis, by sex, underlying liver disease etiology, and severity of hepatic dysfunction.PubMed, Web of Science, EMBASE, and major scientific conference sessions were searched without language restriction through 13 January 2021 with additional manual search of bibliographies of relevant articles. Cohort studies of ?100 patients with cirrhosis and ?12 months of follow-up that evaluated the association between sarcopenia, muscle mass and the risk of mortality were included.22 studies with 6965 patients with cirrhosis were included. The pooled prevalence of sarcopenia in patients with cirrhosis was 37.5% overall (95% CI 32.4%-42.8%), higher in male patients, patients with alcohol associated liver disease (ALD), patients with CTP grade C, and when sarcopenia was defined in patients by lumbar 3- skeletal muscle index (L3-SMI). Sarcopenia was associated with the increased risk of mortality in patients with cirrhosis (adjusted-hazard ratio [aHR] 2.30, 95% CI 2.01-2.63), with similar findings in sensitivity analysis of cirrhosis patients without HCC (aHR 2.35, 95% CI 1.95-2.83) and in subgroup analysis by sex, liver disease etiology, and severity of hepatic dysfunction. The association between quantitative muscle mass index and mortality further supports the poor prognosis for patients with sarcopenia (aHR 0.95, 95% CI 0.93-0.98). There was no significant heterogeneity in all analyses.Sarcopenia was highly and independently associated with higher risk of mortality in patients with cirrhosis.The prevalence of sarcopenia and its association with death in patients with cirrhosis remain unclear. This meta-analysis indicated that sarcopenia affected about one-third of patients with cirrhosis and up to 50% in patients with ALD or Child's class C cirrhosis. Sarcopenia was independently associated with about 2-fold higher risk of mortality in patients with cirrhosis. The mortality rate increased with greater severity or longer period of having sarcopenia. Increasing awareness about the importance of sarcopenia in patients with cirrhosis among stakeholders must be prioritized.Copyright © 2021. Published by Elsevier B.V.
JTD Keywords: alcohol associated liver disease, alcohol-associated liver disease, cirrhosis, failure, frailty, impact, list, mass, model, mortality, prognosis, prognostic value, sarcopenia, severe muscle depletion, skeletal muscle index, Alcohol-associated liver disease, Cirrhosis, Liver-transplant candidates, Prognosis, Sarcopenia, Skeletal muscle index
Dhiman, S, Andrian, T, Gonzalez, BS, Tholen, MME, Wang, YY, Albertazzi, L, (2022). Can super-resolution microscopy become a standard characterization technique for materials chemistry? Chemical Science 13, 2152-2166
The characterization of newly synthesized materials is a cornerstone of all chemistry and nanotechnology laboratories. For this purpose, a wide array of analytical techniques have been standardized and are used routinely by laboratories across the globe. With these methods we can understand the structure, dynamics and function of novel molecular architectures and their relations with the desired performance, guiding the development of the next generation of materials. Moreover, one of the challenges in materials chemistry is the lack of reproducibility due to improper publishing of the sample preparation protocol. In this context, the recent adoption of the reporting standard MIRIBEL (Minimum Information Reporting in Bio–Nano Experimental Literature) for material characterization and details of experimental protocols aims to provide complete, reproducible and reliable sample preparation for the scientific community. Thus, MIRIBEL should be immediately adopted in publications by scientific journals to overcome this challenge. Besides current standard spectroscopy and microscopy techniques, there is a constant development of novel technologies that aim to help chemists unveil the structure of complex materials. Among them super-resolution microscopy (SRM), an optical technique that bypasses the diffraction limit of light, has facilitated the study of synthetic materials with multicolor ability and minimal invasiveness at nanometric resolution. Although still in its infancy, the potential of SRM to unveil the structure, dynamics and function of complex synthetic architectures has been highlighted in pioneering reports during the last few years. Currently, SRM is a sophisticated technique with many challenges in sample preparation, data analysis, environmental control and automation, and moreover the instrumentation is still expensive. Therefore, SRM is currently limited to expert users and is not implemented in characterization routines. This perspective discusses the potential of SRM to transition from a niche technique to a standard routine method for material characterization. We propose a roadmap for the necessary developments required for this purpose based on a collaborative effort from scientists and engineers across disciplines.
JTD Keywords: blinking, fluorophore, intramolecular spirocyclization, localization, nanoparticles, resolution limit, reveals, single-molecule fluorescence, stimulated-emission, Characterization techniques, Diffraction, Distributed computer systems, Environmental management, Information reporting, Material chemistry, Materials characterization, Minimum information, Optical reconstruction microscopy, Optical resolving power, Sample preparation, Structure dynamics, Structure functions, Super-resolution microscopy, Synthesized materials
Sans, J, Arnau, M, Sanz, V, Turon, P, Alemán, C, (2022). Polarized Hydroxyapatite: New Insights and Future Perspectives Through Systematic Electrical Characterization at the Interface Advanced Materials Interfaces 9, 2101631
JTD Keywords: amino-acids, catalysis, dopant-free hydroxyapatite, electrical properties, electrophotosynthesis, nitrogen, thermally-stimulated polarization, Advanced materials, Biocompatibility, Biomedical applications, Brushite, Doped hydroxyapatites, Electric voltage, Electrical characterization, Electrochemical impedance spectroscopy, Equivalent circuits, Future perspectives, Highest temperature, Hydroxyapatite, Interfaces (materials), Material interfaces, Medical applications, Polarization, Polarization conditions, Surface-charges, Technological applications
Murar, M, Albertazzi, L, Pujals, S, (2022). Advanced Optical Imaging-Guided Nanotheranostics toward Personalized Cancer Drug Delivery Nanomaterials 12, 399
Nanomedicine involves the use of nanotechnology for clinical applications and holds promise to improve treatments. Recent developments offer new hope for cancer detection, prevention and treatment; however, being a heterogenous disorder, cancer calls for a more targeted treatment approach. Personalized Medicine (PM) aims to revolutionize cancer therapy by matching the most effective treatment to individual patients. Nanotheranostics comprise a combination of therapy and diagnostic imaging incorporated in a nanosystem and are developed to fulfill the promise of PM by helping in the selection of treatments, the objective monitoring of response and the planning of follow-up therapy. Although well-established imaging techniques, such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT), Positron Emission Tomography (PET) and Single-Photon Emission Computed Tomography (SPECT), are primarily used in the development of theranostics, Optical Imaging (OI) offers some advantages, such as high sensitivity, spatial and temporal resolution and less invasiveness. Additionally, it allows for multiplexing, using multi-color imaging and DNA barcoding, which further aids in the development of personalized treatments. Recent advances have also given rise to techniques permitting better penetration, opening new doors for OI-guided nanotheranostics. In this review, we describe in detail these recent advances that may be used to design and develop efficient and specific nanotheranostics for personalized cancer drug delivery. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
JTD Keywords: 5-aminolevulinic acid, cancer, contrast agents, in-vivo, malignant gliomas, multifunctional nanoparticles, nanomedicine, optical imaging, ovarian-cancer, personalized medicine, quantum dots, silica nanoparticles, targeted probes, theranostics, Cancer, Nanomedicine, Optical imaging, Personalized medicine, Superparamagnetic iron-oxide, Theranostics
Solorzano, A, Eichmann, J, Fernandez, L, Ziems, B, Jimenez-Soto, JM, Marco, S, Fonollosa, J, (2022). Early fire detection based on gas sensor arrays: Multivariate calibration and validation SENSORS AND ACTUATORS B-CHEMICAL 352, 130961
Smoldering fires are characterized by the production of early gas emissions that can include high levels of CO and Volatile Organic Compounds (VOCs) due to pyrolysis or thermal degradation. Nowadays, standalone CO sensors, smoke detectors, or a combination of these, are standard components for fire alarm systems. While gas sensor arrays together with pattern recognition techniques are a valuable alternative for early fire detection, in practice they have certain drawbacks-they can detect early gas emissions, but can show low immunity to nuisances, and sensor time drift can render calibration models obsolete. In this work, we explore the performance of a gas sensor array for detecting smoldering and plastic fires while ensuring the rejection of a set of nuisances. We conducted variety of fire and nuisance experiments in a validated standard fire room (240 m(3)). Using PLS-DA and SVM, we evaluate the performance of different multivariate calibration models for this dataset. We show that calibration models remain predictive after several months, but perfect performance is not achieved. For example, 4 months after calibration, a PLS-DA model provides 100% specificity and 85% sensitivity since the system has difficulties in detecting plastic fires, whose signatures are close to nuisance scenarios. Nevertheless, our results show that systems based on gas sensor arrays are able to provide faster fire alarm response than conventional smoke-based fire alarms. We also propose the use of small-scale fire experiments to increase the number of calibration conditions at a reduced cost. Our results show that this is an effective way to increase the performance of the model, even when evaluated on a standard fire room. Finally, the acquired datasets are made publicly available to the community (doi: 10.5281/zenodo.5643074).
JTD Keywords: Calibration, Chemical sensors, Co2, Early fire, Early fire detection, En-54, Fire alarm, Fire detection, Fire room, Fires, Gas detectors, Gas emissions, Gas sensors, Pattern recognition, Public dataset, Sensor arrays, Sensors array, Signatures, Smoke, Smoke detector, Smoke detectors, Standard fire, Standard fire room, Support vector machines, Temperature, Toxicity, Volatile organic compounds
de Oliveira, LF, Mallafré-Muro, C, Giner, J, Perea, L, Sibila, O, Pardo, A, Marco, S, (2022). Breath analysis using electronic nose and gas chromatography-mass spectrometry: A pilot study on bronchial infections in bronchiectasis CLINICA CHIMICA ACTA 526, 6-13
Background and aims: In this work, breath samples from clinically stable bronchiectasis patients with and without bronchial infections by Pseudomonas Aeruginosa- PA) were collected and chemically analysed to determine if they have clinical value in the monitoring of these patients. Materials and methods: A cohort was recruited inviting bronchiectasis patients (25) and controls (9). Among the former group, 12 members were suffering PA infection. Breath samples were collected in Tedlar bags and analyzed by e-nose and Gas Chromatography-Mass Spectrometry (GC-MS). The obtained data were analyzed by chemometric methods to determine their discriminant power in regards to their health condition. Results were evaluated with blind samples. Results: Breath analysis by electronic nose successfully separated the three groups with an overall classification rate of 84% for the three-class classification problem. The best discrimination was obtained between control and bronchiectasis with PA infection samples 100% (CI95%: 84–100%) on external validation and the results were confirmed by permutation tests. The discrimination analysis by GC-MS provided good results but did not reach proper statistical significance after a permutation test. Conclusions: Breath sample analysis by electronic nose followed by proper predictive models successfully differentiated between control, Bronchiectasis and Bronchiectasis PA samples. © 2021 The Author(s)
JTD Keywords: biomarkers, breath analysis, bronchiectasis, diagnosis, e-nose, fingerprints, gc-ms, identification, lung-cancer, partial least-squares, pseudomonas-aeruginosa, signal processing, validation, volatile organic-compounds, Airway bacterial-colonization, Breath analysis, Bronchiectasis, E-nose, Gc-ms, Signal processing
Martí, D, Alemán, C, Ainsley, J, Ahumada, O, Torras, J, (2022). IgG1-b12–HIV-gp120 Interface in Solution: A Computational Study Journal of Chemical Information and Modeling 62, 359-371
The use of broadly neutralizing antibodies against human immunodeficiency virus type 1 (HIV-1) has been shown to be a promising therapeutic modality in the prevention of HIV infection. Understanding the b12-gp120 binding mechanism under physiological conditions may assist the development of more broadly effective antibodies. In this work, the main conformations and interactions between the receptor-binding domain (RBD) of spike glycoprotein gp120 of HIV-1 and the IgG1-b12 mAb are studied. Accelerated molecular dynamics (aMD) and ab initio hybrid molecular dynamics have been combined to determine the most persistent interactions between the most populated conformations of the antibody-antigen complex under physiological conditions. The results show the most persistent receptor-binding mapping in the conformations of the antibody-antigen interface in solution. The binding-free-energy decomposition reveals a small enhancement in the contribution played by the CDR-H3 region to the b12-gp120 interface compared to the crystal structure.
JTD Keywords: antibody, complex, functionals, gp120 envelope glycoprotein, hiv, immunodeficiency-virus, noncovalent interactions, simulations, software integration, Ab initio, Accelerated molecular dynamics, Accelerated molecular-dynamics, Antibodies, Antigens, Binding energy, Binding mechanisms, Computational studies, Crystal structure, Diseases, Free energy, Hiv infection, Human immunodeficiency virus, Molecular dynamics, Neutralizing antibodies, Physiological condition, Physiology, Receptor-binding domains, Therapeutic modality, Viruses
Arista-Romero, M, Delcanale, P, Pujals, S, Albertazzi, L, (2022). Nanoscale Mapping of Recombinant Viral Proteins: From Cells to Virus-Like Particles ACS Photonics 9, 101-109
Influenza recombinant proteins and virus-like particles (VLPs) play an important role in vaccine development (e.g., CadiFluS). However, their production from mammalian cells suffers from low yields and lack of control of the final VLPs. To improve these issues, characterization techniques able to visualize and quantify the different steps of the process are needed. Fluorescence microscopy represents a powerful tool able to image multiple protein targets; however, its limited resolution hinders the study of viral constructs. Here, we propose the use of super-resolution microscopy and in particular of DNA-point accumulation for imaging in nanoscale topography (DNA-PAINT) microscopy as a characterization method for recombinant viral proteins on both cells and VLPs. We were able to quantify the amount of the three main influenza proteins (hemagglutinin (HA), neuraminidase (NA), and ion channel matrix protein 2 (M2)) per cell and per VLP with nanometer resolution and single-molecule sensitivity, proving that DNA-PAINT is a powerful technique to characterize recombinant viral constructs.
JTD Keywords: dna-paint, hemagglutinin, influenza, neuraminidase, paint, recombinant proteins, single-molecule localization microscopy, single-particle analysis, virus-like particles, Dna-paint, Hemagglutinin, Influenza, Neuraminidase, Paint, Recombinant proteins, Single particle analysis, Single-molecule localization microscopy, Single-particle analysis, Super-resolution microscopy, Superresolution microscopy, Virus-like particles
Gawish, R, Starkl, P, Pimenov, L, Hladik, A, Lakovits, K, Oberndorfer, F, Cronin, SJF, Ohradanova-Repic, A, Wirnsberger, G, Agerer, B, Endler, L, Capraz, T, Perthold, JW, Cikes, D, Koglgruber, R, Hagelkruys, A, Montserrat, N, Mirazimi, A, Boon, L, Stockinger, H, Bergthaler, A, Oostenbrink, C, Penninger, JM, Knapp, S, (2022). ACE2 is the critical in vivo receptor for SARS-CoV-2 in a novel COVID-19 mouse model with TNF-and IFNy-driven immunopathology eLife 11, e74623
Despite tremendous progress in the understanding of COVID-19, mechanistic insight into immunological, disease-driving factors remains limited. We generated maVie16, a mouse-adapted SARS-CoV-2, by serial passaging of a human isolate. In silico modeling revealed how only three Spike mutations of maVie16 enhanced interaction with murine ACE2. maVie16 induced profound pathology in BALB/c and C57BL/6 mice, and the resulting mouse COVID-19 (mCOVID-19) replicated critical aspects of human disease, including early lymphopenia, pulmonary immune cell infiltration, pneumonia, and specific adaptive immunity. Inhibition of the proinflammatory cyto-kines IFN? and TNF substantially reduced immunopathology. Importantly, genetic ACE2-deficiency completely prevented mCOVID-19 development. Finally, inhalation therapy with recombinant ACE2 fully protected mice from mCOVID-19, revealing a novel and efficient treatment. Thus, we here present maVie16 as a new tool to model COVID-19 for the discovery of new therapies and show that disease severity is determined by cytokine-driven immunopathology and critically dependent on ACE2 in vivo. © Gawish et al.
JTD Keywords: covid-19 mouse model, covid-19 therapy, cytokine storm, immunology, inflammation, mavie16, mouse, mouse-adapted sars-cov-2, program, recombinant soluble ace2, tmprss2, Adaptive immunity, Angiotensin converting enzyme 2, Angiotensin-converting enzyme 2, Animal, Animal cell, Animal experiment, Animal model, Animal tissue, Animals, Apoptosis, Article, Bagg albino mouse, Breathing rate, Bronchoalveolar lavage fluid, C57bl mouse, Cell composition, Cell infiltration, Controlled study, Coronavirus disease 2019, Coronavirus spike glycoprotein, Covid-19, Cytokeratin 18, Cytokine production, Dipeptidyl carboxypeptidase, Disease model, Disease models, animal, Disease severity, Drosophila-melanogaster, Enzyme linked immunosorbent assay, Expression vector, Flow cytometry, Gamma interferon, Gene editing, Gene expression, Gene mutation, Genetic engineering, Genetics, Glycosylation, High mobility group b1 protein, Histology, Histopathology, Immune response, Immunocompetent cell, Immunology, Immunopathology, Interferon-gamma, Interleukin 2, Metabolism, Mice, inbred balb c, Mice, inbred c57bl, Mouse-adapted sars-cov-2, Myeloperoxidase, Neuropilin 1, Nonhuman, Nucleocapsid protein, Pathogenicity, Peptidyl-dipeptidase a, Pyroptosis, Recombinant soluble ace2, Renin angiotensin aldosterone system, Rna extraction, Rna isolation, Sars-cov-2, Severe acute respiratory syndrome coronavirus 2, Spike glycoprotein, coronavirus, T lymphocyte activation, Trabecular meshwork, Tumor necrosis factor, Virology, Virus load, Virus replication, Virus transmission, Virus virulence
dos Santos, FP, Verschure, PFMJ, (2022). Excitatory-Inhibitory Homeostasis and Diaschisis: Tying the Local and Global Scales in the Post-stroke Cortex Frontiers in Systems Neuroscience 15, 806544
Maintaining a balance between excitatory and inhibitory activity is an essential feature of neural networks of the neocortex. In the face of perturbations in the levels of excitation to cortical neurons, synapses adjust to maintain excitatory-inhibitory (EI) balance. In this review, we summarize research on this EI homeostasis in the neocortex, using stroke as our case study, and in particular the loss of excitation to distant cortical regions after focal lesions. Widespread changes following a localized lesion, a phenomenon known as diaschisis, are not only related to excitability, but also observed with respect to functional connectivity. Here, we highlight the main findings regarding the evolution of excitability and functional cortical networks during the process of post-stroke recovery, and how both are related to functional recovery. We show that cortical reorganization at a global scale can be explained from the perspective of EI homeostasis. Indeed, recovery of functional networks is paralleled by increases in excitability across the cortex. These adaptive changes likely result from plasticity mechanisms such as synaptic scaling and are linked to EI homeostasis, providing a possible target for future therapeutic strategies in the process of rehabilitation. In addition, we address the difficulty of simultaneously studying these multiscale processes by presenting recent advances in large-scale modeling of the human cortex in the contexts of stroke and EI homeostasis, suggesting computational modeling as a powerful tool to tie the meso- and macro-scale processes of recovery in stroke patients. Copyright © 2022 Páscoa dos Santos and Verschure.
JTD Keywords: balanced excitation, canonical microcircuit, cerebral-cortex, cortical excitability, cortical reorganization, diaschisis, excitability, excitatory-inhibitory balance, functional networks, homeostatic plasticity, ischemic-stroke, neuronal avalanches, photothrombotic lesions, state functional connectivity, whole-brain models, Algorithm, Biological marker, Brain, Brain cell, Brain cortex, Brain function, Brain radiography, Cerebrovascular accident, Cortical reorganization, Diaschisis, Down regulation, Excitability, Excitatory-inhibitory balance, Fluorine magnetic resonance imaging, Functional networks, Homeostasis, Homeostatic plasticity, Human, Motor dysfunction, Neuromodulation, Plasticity, Pyramidal nerve cell, Review, Simulation, Stroke, Stroke patient, Theta-burst stimulation, Visual cortex
Boloix, A, Feiner-Gracia, N, Kober, M, Repetto, J, Pascarella, R, Soriano, A, Masanas, M, Segovia, N, Vargas-Nadal, G, Merlo-Mas, J, Danino, D, Abutbul-Ionita, I, Foradada, L, Roma, J, Cordoba, A, Sala, S, Toledo, JS, Gallego, S, Veciana, J, Albertazzi, L, Segura, MF, Ventosa, N, (2022). Engineering pH-Sensitive Stable Nanovesicles for Delivery of MicroRNA Therapeutics Small 18, 2101959
MicroRNAs (miRNAs) are small non-coding endogenous RNAs, which are attracting a growing interest as therapeutic molecules due to their central role in major diseases. However, the transformation of these biomolecules into drugs is limited due to their unstability in the bloodstream, caused by nucleases abundantly present in the blood, and poor capacity to enter cells. The conjugation of miRNAs to nanoparticles (NPs) could be an effective strategy for their clinical delivery. Herein, the engineering of non-liposomal lipid nanovesicles, named quatsomes (QS), for the delivery of miRNAs and other small RNAs into the cytosol of tumor cells, triggering a tumor-suppressive response is reported. The engineered pH-sensitive nanovesicles have controlled structure (unilamellar), size (<150 nm) and composition. These nanovesicles are colloidal stable (>24 weeks), and are prepared by a green, GMP compliant, and scalable one-step procedure, which are all unavoidable requirements for the arrival to the clinical practice of NP based miRNA therapeutics. Furthermore, QS protect miRNAs from RNAses and when injected intravenously, deliver them into liver, lung, and neuroblastoma xenografts tumors. These stable nanovesicles with tunable pH sensitiveness constitute an attractive platform for the efficient delivery of miRNAs and other small RNAs with therapeutic activity and their exploitation in the clinics.
JTD Keywords: cancer therapy, mirnas delivery, nanocarriers, nanovesicles, neuroblastoma, pediatric cancer, quatsomes, Biodistribution, Cancer therapy, Cell engineering, Cells, Cholesterol, Controlled drug delivery, Diseases, Dna, Dysregulated ph, Lipoplex, Microrna delivery, Mirnas delivery, Nanocarriers, Nanoparticles, Nanovesicle, Nanovesicles, Neuroblastoma, Neuroblastomas, Pediatric cancer, Ph sensitive, Ph sensors, Quatsome, Quatsomes, Rna, Sirna, Sirna delivery, Sirnas delivery, Small interfering rna, Small rna, Targeted drug delivery, Tumors, Vesicles
Guallar-Garrido, S, Almiñana-Rapún, F, Campo-Pérez, V, Torrents, E, Luquin, M, Julián, E, (2022). BCG Substrains Change Their Outermost Surface as a Function of Growth Media Vaccines 10, 40
Mycobacterium bovis bacillus Calmette-Guérin (BCG) efficacy as an immunotherapy tool can be influenced by the genetic background or immune status of the treated population and by the BCG substrain used. BCG comprises several substrains with genetic differences that elicit diverse phenotypic characteristics. Moreover, modifications of phenotypic characteristics can be influenced by culture conditions. However, several culture media formulations are used worldwide to produce BCG. To elucidate the influence of growth conditions on BCG characteristics, five different substrains were grown on two culture media, and the lipidic profile and physico-chemical properties were evaluated. Our results show that each BCG substrain displays a variety of lipidic profiles on the outermost surface depending on the growth conditions. These modifications lead to a breadth of hydrophobicity patterns and a different ability to reduce neutral red dye within the same BCG substrain, suggesting the influence of BCG growth conditions on the interaction between BCG cells and host cells.
JTD Keywords: cell wall, efficacy, glycerol, hydrophobicity, lipid, neutral red, pdim, pgl, protein, strains, viability, virulence, Acylglycerol, Albumin, Article, Asparagine, Bacterial cell wall, Bacterial gene, Bacterium culture, Bcg vaccine, Catalase, Cell wall, Chloroform, Controlled study, Escherichia coli, Gene expression, Genomic dna, Glycerol, Glycerol monomycolate, Hexadecane, Housekeeping gene, Hydrophobicity, Immune response, Immunogenicity, Immunotherapy, Lipid, Lipid fingerprinting, Magnesium sulfate, Mercaptoethanol, Methanol, Methylglyoxal, Molybdatophosphoric acid, Mycobacterium bovis bcg, Neutral red, Nonhuman, Pdim, Petroleum ether, Pgl, Phenotype, Physical chemistry, Real time reverse transcription polymerase chain reaction, Rna 16s, Rna extraction, Rv0577, Staining, Thin layer chromatography, Unclassified drug
Sierra-Agudelo, J, Rodriguez-Trujillo, R, Samitier, J, (2022). Microfluidics for the Isolation and Detection of Circulating Tumor Cells NEW TRENDS IN CANCER FOR THE 21ST CENTURY 1379, 389-412
Nowadays, liquid biopsy represents one of the most promising techniques for early diagnosis, monitoring, and therapy screening of cancer. This novel methodology includes, among other techniques, the isolation, capture, and analysis of circulating tumor cells (CTCs). Nonetheless, the identification of CTC from whole blood is challenging due to their extremely low concentration (1-100 per ml of whole blood), and traditional methods result insufficient in terms of purity, recovery, throughput and/or viability of the processed sample. In this context, the development of microfluidic devices for detecting and isolating CTCs offers a wide range of new opportunities due to their excellent properties for cell manipulation and the advantages to integrate and bring different laboratory processes into the microscale improving the sensitivity, portability, reducing cost and time. This chapter explores current and recent microfluidic approaches that have been developed for the analysis and detection of CTCs, which involve cell capture methods based on affinity binding and label-free methods and detection based on electrical, chemical, and optical sensors. All the exposed technologies seek to overcome the limitations of commercial systems for the analysis and isolation of CTCs, as well as to provide extended analysis that will allow the development of novel and more efficient diagnostic tools.
JTD Keywords: Cancer detection, Cancer diagnosis, Cancer-cells, Capture, Chip, Circulating tumor cells, Enrichment, Label-free isolation, Liquid biopsy, Microchannel, Microfluidics, Separation, Ultra-fast
Ballester, BR, Antenucci, F, Maier, M, Coolen, ACC, Verschure, PFMJ, (2021). Estimating upper-extremity function from kinematics in stroke patients following goal-oriented computer-based training Journal of NeuroEngineering and Rehabilitation 18, 186
Introduction: After a stroke, a wide range of deficits can occur with varying onset latencies. As a result, assessing impairment and recovery are enormous challenges in neurorehabilitation. Although several clinical scales are generally accepted, they are time-consuming, show high inter-rater variability, have low ecological validity, and are vulnerable to biases introduced by compensatory movements and action modifications. Alternative methods need to be developed for efficient and objective assessment. In this study, we explore the potential of computer-based body tracking systems and classification tools to estimate the motor impairment of the more affected arm in stroke patients. Methods: We present a method for estimating clinical scores from movement parameters that are extracted from kinematic data recorded during unsupervised computer-based rehabilitation sessions. We identify a number of kinematic descriptors that characterise the patients' hemiparesis (e.g., movement smoothness, work area), we implement a double-noise model and perform a multivariate regression using clinical data from 98 stroke patients who completed a total of 191 sessions with RGS. Results: Our results reveal a new digital biomarker of arm function, the Total Goal-Directed Movement (TGDM), which relates to the patients work area during the execution of goal-oriented reaching movements. The model's performance to estimate FM-UE scores reaches an accuracy of R-2: 0.38 with an error (sigma: 12.8). Next, we evaluate its reliability (r = 0.89 for test-retest), longitudinal external validity (95% true positive rate), sensitivity, and generalisation to other tasks that involve planar reaching movements (R-2: 0.39). The model achieves comparable accuracy also for the Chedoke Arm and Hand Activity Inventory (R-2: 0.40) and Barthel Index (R-2: 0.35). Conclusions: Our results highlight the clinical value of kinematic data collected during unsupervised goal-oriented motor training with the RGS combined with data science techniques, and provide new insight into factors underlying recovery and its biomarkers.
JTD Keywords: interactive feedback, motion classification, motion sensing, multivariate regression, posture monitoring, rehabilitation, stroke, Adult, Aged, Analytic method, Arm movement, Article, Barthel index, Brain hemorrhage, Cerebrovascular accident, Chedoke arm and hand activity inventory, Clinical protocol, Cognitive defect, Computer analysis, Controlled study, Convergent validity, Correlation coefficient, Disease severity, External validity, Female, Fugl meyer assessment for the upper extremity, Functional assessment, Functional status assessment, General health status assessment, Hemiparesis, Human, Interactive feedback, Ischemic stroke, Kinematics, Major clinical study, Male, Mini mental state examination, Motion classification, Motion sensing, Motor analog scale, Movement, Multivariate regression, Muscle function, Posture monitoring, Probability, Recovery, Rehabilitation, Reliability, Retrospective study, Stroke, Stroke patient, Test retest reliability, Therapy, Total goal directed movement, Upper extremities, Upper limb, Upper-limb, Wolf motor function test
Burgués, J, Esclapez, MD, Doñate, S, Marco, S, (2021). RHINOS: A lightweight portable electronic nose for real-time odor quantification in wastewater treatment plants iScience 24, 103371
Quantification of odor emissions in wastewater treatment plants (WWTPs) is key to minimize odor impact to surrounding communities. Odor measurements in WWTPs are usually performed via either expensive and discontinuous olfactometry hydrogen sulfide detectors or via fixed electronic noses. We propose a portable lightweight electronic nose specially designed for real-time odor monitoring in WWTPs using small drones. The so-called RHINOS e-nose allows odor measurements with high spatial resolution, and its accuracy is only slightly worse than that of dynamic olfactometry. The device has been calibrated using odor samples collected in a WWTP in Spain over a period of six months and validated in the same WWTP three weeks after calibration. The promising results obtained support the suitability of the proposed instrument to identify the odor sources having the highest emissions, which may give a useful indication to the plant managers as regards odor control and abatement.© 2021 The Author(s).
JTD Keywords: biofiltration, calibration transfer, chemical sensor arrays, chemistry, drift compensation, engineering, environmental chemical engineering, h2s, model, oxide gas sensors, removal, sensor, system, Chemistry, Engineering, Environmental chemical engineering, Sensor, Sensor system, Variable selection methods
Arboleda, A, Amado, L, Rodriguez, J, Naranjo, F, Giraldo, BF, (2021). A new protocol to compare successful versus failed patients using the electromyographic diaphragm signal in extubation process Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference , 5646-5649
In clinical practice, when a patient is undergoing mechanical ventilation, it is important to identify the optimal moment for extubation, minimizing the risk of failure. However, this prediction remains a challenge in the clinical process. In this work, we propose a new protocol to study the extubation process, including the electromyographic diaphragm signal (diaEMG) recorded through 5-channels with surface electrodes around the diaphragm muscle. First channel corresponds to the electrode on the right. A total of 40 patients in process of withdrawal of mechanical ventilation, undergoing spontaneous breathing tests (SBT), were studied. According to the outcome of the SBT, the patients were classified into two groups: successful (SG: 19 patients) and failure (FG: 21 patients) groups. Parameters extracted from the envelope of each channel of diaEMG in time and frequency domain were studied. After analyzing all channels, the second presented maximum differences when comparing the two groups of patients, with parameters related to root mean square (p = 0.005), moving average (p = 0.001), and upward slope (p = 0.017). The third channel also presented maximum differences in parameters as the time between maximum peak (p = 0.004), and the skewness (p = 0.027). These results suggest that diaphragm EMG signal could contribute to increase the knowledge of the behaviour of respiratory system in these patients and improve the extubation process.Clinical Relevance - This establishes the characterization of success and failure patients in the extubation process. © 2021 IEEE.
JTD Keywords: classification, recognition, Airway extubation, Artificial ventilation, Clinical practices, Clinical process, Diaphragm, Diaphragm muscle, Diaphragms, Electrodes, Electromyographic, Extubation, Frequency domain analysis, Human, Humans, Maximum differences, Mechanical ventilation, New protocol, Respiration, artificial, Respiratory system, Risk of failure, Spontaneous breathing, Surface electrode, Surface emg signals, Thorax, Ventilation, Ventilator weaning
Estrada-Petrocelli, L, Lozano-Garcia, M, Jane, R, Torres, A, (2021). Assessment of the Non-linear Response of the fSampEn on Simulated EMG Signals Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 2021, 5582-5585
Fixed sample entropy (fSampEn) is a promising technique for the analysis of respiratory electromyographic (EMG) signals. Its use has shown outperformance of amplitude-based estimators such as the root mean square (RMS) in the evaluation of respiratory EMG signals with cardiac noise and a high correlation with respiratory signals, allowing changes in respiratory muscle activity to be tracked. However, the relationship between the fSampEn response to a given muscle activation has not been investigated. The aim of this study was to analyze the nature of the fSampEn measurements that are produced as the EMG activity increases linearly. Simulated EMG signals were generated and increased linearly. The effect of the parameters r and the size of the moving window N of the fSampEn were evaluated and compared with those obtained using the RMS. The RMS showed a linear trend throughout the study. A non-linear, sigmoidal-like behavior was found when analyzing the EMG signals using the fSampEn. The lower the values of r, the higher the non-linearity observed in the fSampEn results. Greater moving windows reduced the variation produced by too small values of r.Clinical Relevance - Understanding the inherent non-linear relationship produced when using the fSampEn in EMG recordings will contribute to the improvement of the respiratory muscle activation assessment at different levels of respiratory effort in patients with respiratory conditions, particularly during the inspiratory phase © 2021 IEEE.
JTD Keywords: Breathing muscle, Breathing rate, Electromyography, Entropy, Heart, Human, Humans, Respiratory muscles, Respiratory rate
Villacampa, EG, Larsson, L, Mirzazadeh, R, Kvastad, L, Andersson, A, Mollbrink, A, Kokaraki, G, Monteil, V, Schultz, N, Appelberg, KS, Montserrat, N, Zhang, HB, Penninger, JM, Miesbach, W, Mirazimi, A, Carlson, J, Lundeberg, J, (2021). Genome-wide spatial expression profiling in formalin-fixed tissues Cell Genomics 1, 100065
Formalin-fixed paraffin embedding (FFPE) is the most widespread long-term tissue preservation approach. Here, we report a procedure to perform genome-wide spatial analysis of mRNA in FFPE-fixed tissue sections, using well-established, commercially available methods for imaging and spatial barcoding using slides spotted with barcoded oligo(dT) probes to capture the 3' end of mRNA molecules in tissue sections. We applied this method for expression profiling and cell type mapping in coronal sections from the mouse brain to demonstrate the method's capability to delineate anatomical regions from a molecular perspective. We also profiled the spatial composition of transcriptomic signatures in two ovarian carcinosarcoma samples, exemplifying the method's potential to elucidate molecular mechanisms in heterogeneous clinical samples. Finally, we demonstrate the applicability of the assay to characterize human lung and kidney organoids and a human lung biopsy specimen infected with SARS-CoV-2. We anticipate that genome-wide spatial gene expression profiling in FFPE biospecimens will be used for retrospective analysis of biobank samples, which will facilitate longitudinal studies of biological processes and biomarker discovery.© 2021 The Authors.
JTD Keywords: colonic transit, gut, intestinal motility, ld score regression, metaanalysis, nervous-system, neurotrophic factor, population, severity, Covid-19, Ffpe, Genome-wide, Irritable-bowel-syndrome, Mouse brain, Organoids, Ovarian carcinosarcoma, Pfa, Sars-cov-2, Spatial transcriptomics, Visium
Chausse, V, Schieber, R, Raymond, Y, Ségry, B, Sabaté, R, Kolandaivelu, K, Ginebra, MP, Pegueroles, M, (2021). Solvent-cast direct-writing as a fabrication strategy for radiopaque stents Additive Manufacturing 48, 102392
JTD Keywords: biocompatibility, bioresorbable stents, degradation, mechanical-properties, poly(epsilon-caprolactone), poly-l-lactic acid, polylactide, radiopacity, thermogel, x-ray imaging, Barium sulfate, Biocompatibility, Bioresorbable, Bioresorbable scaffolds, Bioresorbable stent, Bioresorbable stents, Blood vessels, Computerized tomography, Controlled drug delivery, Coronary heart disease, Direct-writing, Endothelial cells, Fabrication strategies, Injection molding, Lactic acid, Poly-l-lactic acid, Poly-l-lactic acids, Radiopacity, Scaffolds (biology), Solvent cast, Solvent-cast direct-writing, Solvents, Stents, Struts, Sulfur compounds, Targeted drug delivery, X-ray imaging
del-Mazo-Barbara, L, Ginebra, MP, (2021). Rheological characterisation of ceramic inks for 3D direct ink writing: A review JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 41, 18-33
3D printing is a competitive manufacturing technology, which has opened up new possibilities for the fabrication of complex ceramic structures and customised parts. Extrusion-based technologies, also known as direct ink writing (DIW) or robocasting, are amongst the most used for ceramic materials. In them, the rheological properties of the ink play a crucial role, determining both the extrudability of the paste and the shape fidelity of the printed parts. However, comprehensive rheological studies of printable ceramic inks are scarce and may be difficult to understand for non-specialists. The aim of this review is to provide an overview of the main types of ceramic ink formulations developed for DIW and a detailed description of the more relevant rheological tests for assessing the printability of ceramic pastes. Moreover, the key rheological parameters are identified and linked to printability aspects, including the values reported in the literature for different ink compositions.
JTD Keywords: 3-dimensional structures, behavior, deposition, direct ink writing, freeform fabrication, gelation, glass scaffolds, mechanical-properties, printability, rheology, robocasting, suspensions, 3d printing, Direct ink writing, Phosphate scaffolds, Printability, Rheology, Robocasting
Farre, R, Rodriguez-Lazaro, MA, Dinh-Xuan, AT, Pons-Odena, M, Navajas, D, Gozal, D, (2021). A low-cost, easy-to-assemble device to prevent infant hyperthermia under conditions of high thermal stress International Journal of Environmental Research and Public Health 18, 13382
High ambient temperature and humidity greatly increase the risk of hyperthermia and mortality, particularly in infants, who are especially prone to dehydration. World areas at high risk of heat stress include many of the low-and middle-income countries (LMICs) where most of their inhabitants have no access to air conditioning. This study aimed to design, evaluate, and test a novel low-cost and easy-to-assemble device aimed at preventing the risk of infant hyperthermia in LMICs. The device is based on optimizing negative heat transfer from a small amount of ice and transferring it directly to the infant by airflow of refrigerated air. As a proof of concept, a device was assembled mainly using recycled materials, and its performance was assessed under laboratory-controlled conditions in a climatic chamber mimicking realistic stress conditions of high temperature and humidity. The device, which can be assembled by any layperson using easily available materials, provided sufficient refrigerating capacity for several hours from just 1–2 kg of ice obtained from a domestic freezer. Thus, application of this novel device may serve to attenuate the adverse effects of heat stress in infants, particularly in the context of the evolving climatic change trends. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
JTD Keywords: air conditioning, ambient-temperature, death, heat, heat index, heat shock, heatwave, high ambient temperature, hyperthermia, low-cost refrigeration, low-middle income countries, mortality, negative heat transfer, Air conditioning, Algorithm, Article, Climate change, Cost benefit analysis, Environmental temperature, Heat index, Heat shock, Heat stress, Heat transfer, Heating, Heatwave, High ambient temperature, High temperature, Humidity, Hyperthermia, Low income country, Low-cost refrigeration, Low-middle income countries, Middle income country, Middle-income countries, Negative heat transfer, Prevention study, Refrigeration, Temperature stress, Thawing
Lozano, H, Millan-Solsona, R, Blanco-Cabra, N, Fabregas, R, Torrents, E, Gomila, G, (2021). Electrical properties of outer membrane extensions from Shewanella oneidensis MR-1 Nanoscale 13, 18754-18762
Outer membrane extensions from the metal-reducing bacterium Shewanella oneidensis MR-1 show an insulating behavior in dry air environment as measured by scanning dielectric microscopy.
JTD Keywords: constant, dielectric polarization, microbial nanowires, nanoscale, transport, Air environment, Bacteria, Bacterial cells, Bacterial nanowires, Dry air, Electron transport, Electrons, Metal-reducing bacteria, Outer membrane, Periplasm, Phase-minerals, Proteins, Shewanella, Shewanella oneidensis mr-1, Solid phasis, Solid-phase, Space division multiple access, Tubulars
Prieto, A, Bernabeu, M, Sánchez-Herrero, JF, Pérez-Bosque, A, Mir, L, Bäuer, C, Colladcy, C, Hüttener, M, Juárez, A, (2021). Modulation of AggR levels reveals features of virulence regulation in enteroaggregative E. coli Communications Biology 4, 1295
Enteroaggregative Escherichia coli (EAEC) strains are one of the diarrheagenic pathotypes. EAEC strains harbor a virulence plasmid (pAA2) that encodes, among other virulence determinants, the aggR gene. The expression of the AggR protein leads to the expression of several virulence determinants in both plasmids and chromosomes. In this work, we describe a novel mechanism that influences AggR expression. Because of the absence of a Rho-independent terminator in the 3?UTR, aggR transcripts extend far beyond the aggR ORF. These transcripts are prone to PNPase-mediated degradation. Structural alterations in the 3?UTR result in increased aggR transcript stability, leading to increased AggR levels. We therefore investigated the effect of increased AggR levels on EAEC virulence. Upon finding the previously described AggR-dependent virulence factors, we detected novel AggR-regulated genes that may play relevant roles in EAEC virulence. Mutants exhibiting high AggR levels because of structural alterations in the aggR 3?UTR show increased mobility and increased pAA2 conjugation frequency. Furthermore, among the genes exhibiting increased fold change values, we could identify those of metabolic pathways that promote increased degradation of arginine, fatty acids and gamma-aminobutyric acid (GABA), respectively. In this paper, we discuss how the AggR-dependent increase in specific metabolic pathways activity may contribute to EAEC virulence.
JTD Keywords: aggregative adherence, arginine metabolism, biofilm formation, escherichia-coli, gene-expression, messenger-rna, operon, persistent diarrhea, untranslated region, Aggr protein, e coli, Escherichia coli, Escherichia coli proteins, Fimbria-i expression, Trans-activators, Virulence
Castillo-Escario, Y, Kumru, H, Ferrer-Lluis, I, Vidal, J, Jané, R, (2021). Detection of Sleep-Disordered Breathing in Patients with Spinal Cord Injury Using a Smartphone SENSORS 21, 7182
Patients with spinal cord injury (SCI) have an increased risk of sleep-disordered breathing (SDB), which can lead to serious comorbidities and impact patients’ recovery and quality of life. However, sleep tests are rarely performed on SCI patients, given their multiple health needs and the cost and complexity of diagnostic equipment. The objective of this study was to use a novel smartphone system as a simple non-invasive tool to monitor SDB in SCI patients. We recorded pulse oximetry, acoustic, and accelerometer data using a smartphone during overnight tests in 19 SCI patients and 19 able-bodied controls. Then, we analyzed these signals with automatic algorithms to detect desaturation, apnea, and hypopnea events and monitor sleep position. The apnea–hypopnea index (AHI) was significantly higher in SCI patients than controls (25 ± 15 vs. 9 ± 7, p < 0.001). We found that 63% of SCI patients had moderate-to-severe SDB (AHI ? 15) in contrast to 21% of control subjects. Most SCI patients slept predominantly in supine position, but an increased occurrence of events in supine position was only observed for eight patients. This study highlights the problem of SDB in SCI and provides simple cost-effective sleep monitoring tools to facilitate the detection, understanding, and management of SDB in SCI patients.
JTD Keywords: apnea syndrome, biomedical signal processing, individuals, mhealth, monitoring, nasal resistance, people, position, prevalence, questionnaire, sample, sleep apnea, sleep position, sleep-disordered breathing, smartphone, time, Apnea-hypopnea indices, Biomedical signal processing, Biomedical signals processing, Cost effectiveness, Diagnosis, Mhealth, Monitoring, Noninvasive medical procedures, Oximeters, Oxygen-saturation, Patient rehabilitation, Simple++, Sleep apnea, Sleep position, Sleep research, Sleep-disordered breathing, Smart phones, Smartphone, Smartphones, Spinal cord injury, Spinal cord injury patients
Raymond, Y, Thorel, E, Liversain, M, Riveiro, A, Pou, J, Ginebra, MP, (2021). 3D printing non-cylindrical strands: Morphological and structural implications Additive Manufacturing 46, 102129
Conventional direct ink writing uses circular nozzles and, therefore, results in cylindrical strands. 3D printing with non-circular nozzles adds new degrees of freedom to this versatile technology, and allows obtaining structures with higher specific surface area or even introducing concave surfaces in the printed architecture. This is an enticing prospect for countless applications, including tissue engineering, chemical reaction catalysts, water evaporators and electrochemical energy storage devices. Despite this, it has been hardly explored by the 3D-printing community. Herein, we develop for the first time 3D printed structures with complex filament section morphologies using a custom-made modular nozzle and a self-setting ceramic ink. The fast elastic recovery of the ink allows obtaining good shape fidelity in the printed filaments, permitting the creation of intricate surfaces with up to 30% concavity and increasing up to 2.5 times the specific surface area compared to cylindrical strands. The use of non-circular nozzles introduces some specific constraints in the printing process. The geometry of the nozzle determines the stable printing directions, and nozzle orientation becomes a critical parameter to achieve a stable printing. Strand torsion, a phenomenon that remains unnoticed with circular nozzles, may result in relevant changes in the geometrical features of the printed structures.
JTD Keywords: calcium phosphate, ceramic, ceramics, flow, geometry, microextrusion, robocasting, Calcium phosphate, Ceramic, Direct ink writing, Microextrusion, Robocasting, Scaffolds
Balakrishnan, H, Fabregas, R, Millan-Solsona, R, Fumagalli, L, Gomila, G, (2021). Spatial Resolution and Capacitive Coupling in the Characterization of Nanowire Nanocomposites by Scanning Dielectric Microscopy MICROSCOPY AND MICROANALYSIS 27, 1026-1034
Nanowire-based nanocomposite materials are being developed as transparent and flexible electrodes or as stretchable conductors and dielectrics for biosensing. Here, we theoretically investigate the use of scanning dielectric microscopy (SDM) to characterize these materials in a nondestructive way, with a special focus on the achievable spatial resolution and the possibility of detection of the capacitive coupling between nearby nanowires. Numerical calculations with models involving single and multiple buried nanowires have been performed. We demonstrate that the capacitance gradient spread function of a single buried nanowire consists of a modified Lorenzianan with a cubic decay. We show that the achievable spatial resolution can be determined with good accuracy with the help of this spread function. It is shown that, in general, the spatial resolution worsens when any system parameter decreases the maximum of the nanowire spread function or increases its width, or both. Finally, we show that SDM measurements are also sensitive to the capacitive coupling between nearby nanowires. This latter result is of utmost relevance since the macroscopic electric properties of nanowire nanocomposites largely depend on the electric interaction between nearby nanowires. The present results show that SDM can be a valuable nondestructive subsurface characterization technique for nanowire nanocomposite materials.
JTD Keywords: depth, electrodes, nanocomposites, nanowires, sdm, spatial resolution, subsurface, tomography, Capacitive coupling, Force microscopy, Nanocomposites, Nanowires, Sdm, Spatial resolution, Subsurface
Rubí-Sans, G, Nyga, A, Rebollo, E, Pérez-Amodio, S, Otero, J, Navajas, D, Mateos-Timoneda, MA, Engel, E, (2021). Development of Cell-Derived Matrices for Three-Dimensional in Vitro Cancer Cell Models ACS Applied Materials & Interfaces 13, 44108-44123
Most morphogenetic and pathological processes are driven by cells responding to the surrounding matrix, such as its composition, architecture, and mechanical properties. Despite increasing evidence for the role of extracellular matrix (ECM) in tissue and disease development, many in vitro substitutes still fail to effectively mimic the native microenvironment. We established a novel method to produce macroscale (>1 cm) mesenchymal cell-derived matrices (CDMs) aimed to mimic the fibrotic tumor microenvironment surrounding epithelial cancer cells. CDMs are produced by human adipose mesenchymal stem cells cultured in sacrificial 3D scaffold templates of fibronectin-coated poly-lactic acid microcarriers (MCs) in the presence of macromolecular crowders. We showed that decellularized CDMs closely mimic the fibrillar protein composition, architecture, and mechanical properties of human fibrotic ECM from cancer masses. CDMs had highly reproducible composition made of collagen types I and III and fibronectin ECM with tunable mechanical properties. Moreover, decellularized and MC-free CDMs were successfully repopulated with cancer cells throughout their 3D structure, and following chemotherapeutic treatment, cancer cells showed greater doxorubicin resistance compared to 3D culture in collagen hydrogels. Collectively, these results support the use of CDMs as a reproducible and tunable tool for developing 3D in vitro cancer models.
JTD Keywords: 3d cell-derived matrices, adipose mesenchymal stem cells, collagen matrix, colorectal adenocarcinoma, cytotoxicity assay, deposition, expansion, extracellular microenvironment, extracellular-matrix, fibronectin, growth, macromolecular crowders, microcarriers, scaffolds, tissue, 3d cell-derived matrices, Adipose mesenchymal stem cells, Antineoplastic agents, Cell culture techniques, three dimensional, Cell line, tumor, Cell survival, Cytotoxicity assay, Decellularized extracellular matrix, Doxorubicin, Drug resistance, neoplasm, Extracellular microenvironment, Humans, Macromolecular crowders, Mesenchymal stem cells, Mesenchymal stem-cells, Microcarriers, Models, biological, Proof of concept study, Tissue scaffolds, Tumor microenvironment
Rial-Hermida, MI, Rey-Rico, A, Blanco-Fernandez, B, Carballo-Pedrares, N, Byrne, EM, Mano, JF, (2021). Recent Progress on Polysaccharide-Based Hydrogels for Controlled Delivery of Therapeutic Biomolecules ACS Biomaterials Science & Engineering 7, 4102-4127
A plethora of applications using polysaccharides have been developed in recent years due to their availability as well as their frequent nontoxicity and biodegradability. These polymers are usually obtained from renewable sources or are byproducts of industrial processes, thus, their use is collaborative in waste management and shows promise for an enhanced sustainable circular economy. Regarding the development of novel delivery systems for biotherapeutics, the potential of polysaccharides is attractive for the previously mentioned properties and also for the possibility of chemical modification of their structures, their ability to form matrixes of diverse architectures and mechanical properties, as well as for their ability to maintain bioactivity following incorporation of the biomolecules into the matrix. Biotherapeutics, such as proteins, growth factors, gene vectors, enzymes, hormones, DNA/RNA, and antibodies are currently in use as major therapeutics in a wide range of pathologies. In the present review, we summarize recent progress in the development of polysaccharide-based hydrogels of diverse nature, alone or in combination with other polymers or drug delivery systems, which have been implemented in the delivery of biotherapeutics in the pharmaceutical and biomedical fields. © 2021 American Chemical Society.
JTD Keywords: biodegradable dextran hydrogels, biotherapeutics, bone morphogenetic protein-2, carrageenan-based hydrogels, chitosan-based hydrogels, controlled delivery, controlled-release, cross-linked hydrogels, growth-factor delivery, hydrogels, in-vitro characterization, polysaccharides, self-healing hydrogel, stimuli-responsiveness, tissue engineering, Antibodies, Bioactivity, Biodegradability, Biomedical fields, Biomolecules, Biotherapeutics, Chemical modification, Circular economy, Controlled delivery, Controlled drug delivery, Delivery systems, Drug delivery system, Functional polymers, Hyaluronic-acid hydrogels, Hydrogels, Industrial processs, Polysaccharides, Recent progress, Renewable sources, Stimuli-responsiveness, Targeted drug delivery, Tissue engineering, Waste management
Calo, Annalisa, Eleta-Lopez, Aitziber, Ondarcuhu, Thierry, Verdaguer, Albert, Bittner, Alexander M, (2021). Nanoscale wetting of single viruses MOLECULES 26, 5184
The epidemic spread of many viral infections is mediated by the environmental conditions and influenced by the ambient humidity. Single virus particles have been mainly visualized by atomic force microscopy (AFM) in liquid conditions, where the effect of the relative humidity on virus topography and surface cannot be systematically assessed. In this work, we employed multi-frequency AFM, simultaneously with standard topography imaging, to study the nanoscale wetting of individual Tobacco Mosaic virions (TMV) from ambient relative humidity to water condensation (RH > 100%). We recorded amplitude and phase vs. distance curves (APD curves) on top of single virions at various RH and converted them into force vs. distance curves. The high sensitivity of multifrequency AFM to visualize condensed water and sub-micrometer droplets, filling gaps between individual TMV particles at RH > 100%, is demonstrated. Dynamic force spectroscopy allows detecting a thin water layer of thickness ⁓1 nm, adsorbed on the outer surface of single TMV particles at RH < 60%.
JTD Keywords: amplitude-modulation am-afm, atomic-force microscopy, capillary, force reconstruction, multifrequency afm, nanoscale wetting, persistence, reconstruction, relative-humidity, surfaces, tobacco mosaic virus (tmv), tobamovirus, transmission, water, Amplitude-modulation am-afm, Force reconstruction, Humidity, Microscopy, atomic force, Multifrequency afm, Nanoscale wetting, Tobacco mosaic virus, Tobacco mosaic virus (tmv), Tobacco mosaic virus (tmv), nanoscale wetting, Tobacco-mosaic-virus, Virion, Water, Wettability
Duran, J, Hervera, A, Markussen, KH, Varea, O, Lopez-Soldado, I, Sun, RC, del Rio, JA, Gentry, MS, Guinovart, JJ, (2021). Astrocytic glycogen accumulation drives the pathophysiology of neurodegeneration in Lafora disease BRAIN 144, 2349-2360
The hallmark of Lafora disease, a fatal neurodegenerative disorder, is the accumulation of intracellular glycogen aggregates called Lafora bodies. Until recently, it was widely believed that brain Lafora bodies were present exclusively in neurons and thus that Lafora disease pathology derived from their accumulation in this cell population. However, recent evidence indicates that Lafora bodies are also present in astrocytes. To define the role of astrocytic Lafora bodies in Lafora disease pathology, we deleted glycogen synthase specifically from astrocytes in a mouse model of the disease (malin(KO)). Strikingly, blocking glycogen synthesis in astrocytes-thus impeding Lafora bodies accumulation in this cell type-prevented the increase in neurodegeneration markers, autophagy impairment, and metabolic changes characteristic of the malin(KO) model. Conversely, mice that over-accumulate glycogen in astrocytes showed an increase in these markers. These results unveil the deleterious consequences of the deregulation of glycogen metabolism in astrocytes and change the perspective that Lafora disease is caused solely by alterations in neurons.
JTD Keywords: Bodies, Deficient mice, Epilepsy, Glycogen, Impairment, Lafora disease, Malin, Modulation, Mouse model, Neurodegeneration, Neuroinflammation, Neurons, Progressive myoclonus epilepsy, Seizure susceptibility, Synthase
Castillo-Escario, Y, Kumru, H, Valls-Solé, J, García-Alen, L, Jané, R, Vidal, J, (2021). Quantitative evaluation of trunk function and the StartReact effect during reaching in patients with cervical and thoracic spinal cord injury Journal of Neural Engineering 18, 0460d2
Objective. Impaired trunk stability is frequent in spinal cord injury (SCI), but there is a lack of quantitative measures for assessing trunk function. Our objectives were to: (a) evaluate trunk muscle activity and movement patterns during a reaching task in SCI patients, (b) compare the impact of cervical (cSCI) and thoracic (tSCI) injuries in trunk function, and (c) investigate the effects of a startling acoustic stimulus (SAS) in these patients. Approach. Electromyographic (EMG) and smartphone accelerometer data were recorded from 15 cSCI patients, nine tSCI patients, and 24 healthy controls, during a reaching task requiring trunk tilting. We calculated the response time (RespT) until pressing a target button, EMG onset latencies and amplitudes, and trunk tilt, lateral deviation, and other movement features from accelerometry. Statistical analysis was applied to analyze the effects of group (cSCI, tSCI, control) and condition (SAS, non-SAS) in each outcome measure. Main results. SCI patients, especially those with cSCI, presented significantly longer RespT and EMG onset latencies than controls. Moreover, in SCI patients, forward trunk tilt was accompanied by significant lateral deviation. RespT and EMG latencies were remarkably shortened by the SAS (the so-called StartReact effect) in tSCI patients and controls, but not in cSCI patients, who also showed higher variability. Significance. The combination of EMG and smartphone accelerometer data can provide quantitative measures for the assessment of trunk function in SCI. Our results show deficits in postural control and compensatory strategies employed by SCI patients, including delayed responses and higher lateral deviations, possibly to improve sitting balance. This is the first study investigating the StartReact responses in trunk muscles in SCI patients and shows that the SAS significantly accelerates RespT in tSCI, but not in cSCI, suggesting an increased cortical control exerted by these patients.
JTD Keywords: accelerometer, electromyography, impairment, individuals, movements, postural stability, reaction-time, reliability, sitting balance, smartphone, spinal cord injury, startle, startreact, strategies, stroke, trunk, Accelerometer, Electromyography, Sitting balance, Smartphone, Spinal cord injury, Startreact, Trunk
Calistri, A, Luganini, A, Mognetti, B, Elder, E, Sibille, G, Conciatori, V, Del Vecchio, C, Sainas, S, Boschi, D, Montserrat, N, Mirazimi, A, Lolli, ML, Gribaudo, G, Parolin, C, (2021). The new generation hdhodh inhibitor meds433 hinders the in vitro replication of sars-cov-2 and other human coronaviruses Microorganisms 9, 1731
Although coronaviruses (CoVs) have long been predicted to cause zoonotic diseases and pandemics with high probability, the lack of effective anti-pan-CoVs drugs rapidly usable against the emerging SARS-CoV-2 actually prevented a promptly therapeutic intervention for COVID-19. Development of host-targeting antivirals could be an alternative strategy for the control of emerging CoVs infections, as they could be quickly repositioned from one pandemic event to another. To contribute to these pandemic preparedness efforts, here we report on the broad-spectrum CoVs antiviral activity of MEDS433, a new inhibitor of the human dihydroorotate dehydrogenase (hDHODH), a key cellular enzyme of the de novo pyrimidine biosynthesis pathway. MEDS433 in-hibited the in vitro replication of hCoV-OC43 and hCoV-229E, as well as of SARS-CoV-2, at low nanomolar range. Notably, the anti-SARS-CoV-2 activity of MEDS433 against SARS-CoV-2 was also observed in kidney organoids generated from human embryonic stem cells. Then, the antiviral activity of MEDS433 was reversed by the addition of exogenous uridine or the product of hDHODH, the orotate, thus confirming hDHODH as the specific target of MEDS433 in hCoVs-infected cells. Taken together, these findings suggest MEDS433 as a potential candidate to develop novel drugs for COVID-19, as well as broad-spectrum antiviral agents exploitable for future CoVs threats.
JTD Keywords: antiviral activity, biosynthesis, broad-spectrum antiviral, combination treatment, coronavirus, dipyridamole, hdhodh inhibitor, organoids, pyrimidine, pyrimidine biosynthesis, sars-cov-2, target, virus-infection, Antiviral activ-ity, Broad-spectrum antiviral, Combination treatment, Coronavirus, Gene-expression, Hdhodh inhibitor, Organoids, Pyrimidine biosynthesis, Sars-cov-2
Barbero-Castillo, A, Riefolo, F, Matera, C, Caldas-Martínez, S, Mateos-Aparicio, P, Weinert, JF, Garrido-Charles, A, Claro, E, Sanchez-Vives, MV, Gorostiza, P, (2021). Control of Brain State Transitions with a Photoswitchable Muscarinic Agonist Advanced Science 8, 2005027
The ability to control neural activity is essential for research not only in basic neuroscience, as spatiotemporal control of activity is a fundamental experimental tool, but also in clinical neurology for therapeutic brain interventions. Transcranial-magnetic, ultrasound, and alternating/direct current (AC/DC) stimulation are some available means of spatiotemporal controlled neuromodulation. There is also light-mediated control, such as optogenetics, which has revolutionized neuroscience research, yet its clinical translation is hampered by the need for gene manipulation. As a drug-based light-mediated control, the effect of a photoswitchable muscarinic agonist (Phthalimide-Azo-Iper (PAI)) on a brain network is evaluated in this study. First, the conditions to manipulate M2 muscarinic receptors with light in the experimental setup are determined. Next, physiological synchronous emergent cortical activity consisting of slow oscillations-as in slow wave sleep-is transformed into a higher frequency pattern in the cerebral cortex, both in vitro and in vivo, as a consequence of PAI activation with light. These results open the way to study cholinergic neuromodulation and to control spatiotemporal patterns of activity in different brain states, their transitions, and their links to cognition and behavior. The approach can be applied to different organisms and does not require genetic manipulation, which would make it translational to humans.
JTD Keywords: brain states, light-mediated control, muscarinic acetylcholine receptors, neuromodulation, Activation, Alternating/direct currents, Animals, Basal forebrain, Brain, Brain states, Clinical research, Clinical translation, Controlled drug delivery, Cortex, Ferrets, Forebrain cholinergic system, Genetic manipulations, Higher frequencies, Hz oscillation, Light‐, Light-mediated control, Mediated control, Mice, Mice, inbred c57bl, Models, animal, Muscarinic acetylcholine receptors, Muscarinic agonists, Muscarinic receptor, Neurology, Neuromodulation, Neurons, Noradrenergic modulation, Parvalbumin-positive interneurons, Photopharmacology, Receptor-binding, Slow, Spatiotemporal control, Spatiotemporal patterns
Andreu, I, Falcones, B, Hurst, S, Chahare, N, Quiroga, X, Le Roux, AL, Kechagia, Z, Beedle, AEM, Elosegui-Artola, A, Trepat, X, Farre, R, Betz, T, Almendros, I, Roca-Cusachs, P, (2021). The force loading rate drives cell mechanosensing through both reinforcement and cytoskeletal softening Nature Communications 12, 4229
Cell response to force regulates essential processes in health and disease. However, the fundamental mechanical variables that cells sense and respond to remain unclear. Here we show that the rate of force application (loading rate) drives mechanosensing, as predicted by a molecular clutch model. By applying dynamic force regimes to cells through substrate stretching, optical tweezers, and atomic force microscopy, we find that increasing loading rates trigger talin-dependent mechanosensing, leading to adhesion growth and reinforcement, and YAP nuclear localization. However, above a given threshold the actin cytoskeleton softens, decreasing loading rates and preventing reinforcement. By stretching rat lungs in vivo, we show that a similar phenomenon may occur. Our results show that cell sensing of external forces and of passive mechanical parameters (like tissue stiffness) can be understood through the same mechanisms, driven by the properties under force of the mechanosensing molecules involved. Cells sense mechanical forces from their environment, but the precise mechanical variable sensed by cells is unclear. Here, the authors show that cells can sense the rate of force application, known as the loading rate, with effects on YAP nuclear localization and cytoskeletal stiffness remodelling.
JTD Keywords: Actin cytoskeleton, Actin filament, Actin-filament, Adhesion, Animal, Animals, Atomic force microscopy, Breathing, Cell, Cell adhesion, Cell culture, Cell nucleus, Cells, cultured, Cytoplasm, Extracellular-matrix, Fibroblast, Fibroblasts, Fibronectin, Frequency, Gene knockdown, Gene knockdown techniques, Genetics, Germfree animal, Integrin, Intracellular signaling peptides and proteins, Knockout mouse, Lung, Male, Mechanotransduction, Mechanotransduction, cellular, Metabolism, Mice, Mice, knockout, Microscopy, atomic force, Mouse, Optical tweezers, Paxillin, Physiology, Primary cell culture, Pxn protein, mouse, Rat, Rats, Rats, sprague-dawley, Respiration, Signal peptide, Softening, Specific pathogen-free organisms, Sprague dawley rat, Stress, Substrate, Substrate rigidity, Talin, Talin protein, mouse, Tln1 protein, mouse, Tln2 protein, mouse, Traction, Transmission, Ultrastructure, Yap-signaling proteins, Yap1 protein, rat
Riefolo, F, Sortino, R, Matera, C, Claro, E, Preda, B, Vitiello, S, Traserra, S, Jimenez, M, Gorostiza, P, (2021). Rational Design of Photochromic Analogues of Tricyclic Drugs JOURNAL OF MEDICINAL CHEMISTRY 64, 9259-9270
Tricyclic chemical structures are the core of many important drugs targeting all neurotransmitter pathways. These medicines enable effective therapies to treat from peptic ulcer disease to psychiatric disorders. However, when administered systemically, they cause serious adverse effects that limit their use. To obtain localized and on-demand pharmacological action using light, we have designed photoisomerizable ligands based on azobenzene that mimic the tricyclic chemical structure and display reversibly controlled activity. Pseudo-analogues of the tricyclic antagonist pirenzepine demonstrate that this is an effective strategy in muscarinic acetylcholine receptors, showing stronger inhibition upon illumination both in vitro and in cardiac atria ex vivo. Despite the applied chemical modifications to make pirenzepine derivatives sensitive to light stimuli, the most potent candidate of the set, cryptozepine-2, maintained a moderate but promising M-1 vs M-2 subtype selectivity. These photoswitchable crypto-azologs of tricyclic drugs might open a general way to spatiotemporally target their therapeutic action while reducing their systemic toxicity and adverse effects.
JTD Keywords: Binding, Dose-response relationship, drug, Drug design, Humans, M1, Molecular structure, Muscarinic antagonists, Pirenzepine, Rat-brain, Receptor, Receptors, muscarinic, Structure-activity relationship
Falcones, B, Sanz-Fraile, H, Marhuenda, E, Mendizábal, I, Cabrera-Aguilera, I, Malandain, N, Uriarte, JJ, Almendros, I, Navajas, D, Weiss, DJ, Farré, R, Otero, J, (2021). Bioprintable lung extracellular matrix hydrogel scaffolds for 3d culture of mesenchymal stromal cells Polymers 13, 2350
Mesenchymal stromal cell (MSC)-based cell therapy in acute respiratory diseases is based on MSC secretion of paracrine factors. Several strategies have proposed to improve this are being explored including pre-conditioning the MSCs prior to administration. We here propose a strategy for improving the therapeutic efficacy of MSCs based on cell preconditioning by growing them in native extracellular matrix (ECM) derived from the lung. To this end, a bioink with tunable stiffness based on decellularized porcine lung ECM hydrogels was developed and characterized. The bioink was suitable for 3D culturing of lung-resident MSCs without the need for additional chemical or physical crosslinking. MSCs showed good viability, and contraction assays showed the existence of cell–matrix interactions in the bioprinted scaffolds. Adhesion capacity and length of the focal adhesions formed were increased for the cells cultured within the lung hydrogel scaffolds. Also, there was more than a 20-fold increase of the expression of the CXCR4 receptor in the 3D-cultured cells compared to the cells cultured in plastic. Secretion of cytokines when cultured in an in vitro model of lung injury showed a decreased secretion of pro-inflammatory mediators for the cells cultured in the 3D scaffolds. Moreover, the morphology of the harvested cells was markedly different with respect to conventionally (2D) cultured MSCs. In conclusion, the developed bioink can be used to bioprint structures aimed to improve preconditioning MSCs for therapeutic purposes.
JTD Keywords: 3d bioprinting, acute lung injury, adhesion, collagen, differentiation, dimension, elastic properties, extracellular matrix, hydrogels, in-vitro, mechanical-properties, mesenchymal stromal cells, microenvironment, potentiate, tissue engineering, 3d bioprinting, Acute lung injury, Extracellular matrix, Hydrogels, Mesenchymal stromal cells, Stem-cells, Tissue engineering
Abramov, A, Maiti, B, Keridou, I, Puiggalí, J, Reiser, O, Díaz, DD, (2021). A pH-Triggered Polymer Degradation or Drug Delivery System by Light-Mediated Cis/Trans Isomerization of o-Hydroxy Cinnamates MACROMOLECULAR RAPID COMMUNICATIONS 42, 2100213
A new methodology for the pH-triggered degradation of polymers or for the release of drugs under visible light irradiation based on the cyclization of ortho-hydroxy-cinnamates (oHC) to coumarins is described. The key oHC structural motif can be readily incorporated into the rational design of novel photocleavable polymers via click chemistry. This main-chain moiety undergoes a fast photocleavage when irradiated with 455 nm light provided that a suitable base is added. A series of polyethylene glycol-alt-ortho-hydroxy cinnamate (polyethylene glycol (PEG)(n)-alt-oHC)-based polymers are synthesized and the time-dependent visible-light initiated cleavage of the photoactive monomer and polymer is investigated in solution by a variety of spectroscopic and chromatographic techniques. The photo-degradation behavior of the water-soluble poly(PEG(2000)-alt-oHC) is investigated within a broad pH range (pH = 2.1-11.8), demonstrating fast degradation at pH 11.8, while the stability of the polymer is greatly enhanced at pH 2.1. Moreover, the neat polymer shows long-term stability under daylight conditions, thus allowing its storage without special precautions. In addition, two water-soluble PEG-based drug-carrier molecules (mPEG(2000)-oHC-benzhydrol/phenol) are synthesized and used for drug delivery studies, monitoring the process by UV-vis spectroscopy in an ON/OFF intermittent manner.
JTD Keywords: coumarins, drug delivery, e/z-double bond isomerization, o-hydroxy cinnamates, polymer degradation, Aliphatic compounds, Antioxidant activity, Antitumor, Chromatographic techniques, Chromatography, Cis/trans isomerization, Controlled drug delivery, Coumarin derivatives, Coumarins, Drug delivery, Drug delivery system, E/z-double bond isomerization, Films, Hydrogels, Image enhancement, Light, Long term stability, O-hydroxy cinnamates, Particles, Photoactive monomers, Photodegradation, Polyethylene glycols, Polyethylenes, Polymer degradation, Responsive polymers, Salts, Structural motifs, Synthesis (chemical), Targeted drug delivery, Visible light photocatalysis, Visible-light irradiation
Ferrer-Lluis, I, Castillo-Escario, Y, Montserrat, JM, Jané, R, (2021). SleepPos app: An automated smartphone application for angle based high resolution sleep position monitoring and treatment SENSORS 21, 4531
Poor sleep quality or disturbed sleep is associated with multiple health conditions. Sleep position affects the severity and occurrence of these complications, and positional therapy is one of the less invasive treatments to deal with them. Sleep positions can be self-reported, which is unreliable, or determined by using specific devices, such as polysomnography, polygraphy or cameras, that can be expensive and difficult to employ at home. The aim of this study is to determine how smartphones could be used to monitor and treat sleep position at home. We divided our research into three tasks: (1) develop an Android smartphone application (‘SleepPos’ app) which monitors angle-based high-resolution sleep position and allows to simultaneously apply positional treatment; (2) test the smartphone application at home coupled with a pulse oximeter; and (3) explore the potential of this tool to detect the positional occurrence of desaturation events. The results show how the ‘SleepPos’ app successfully determined the sleep position and revealed positional patterns of occurrence of desaturation events. The ‘SleepPos’ app also succeeded in applying positional therapy and preventing the subjects from sleeping in the supine sleep position. This study demonstrates how smartphones are capable of reliably monitoring high-resolution sleep position and provide useful clinical information about the positional occurrence of desaturation events.
JTD Keywords: accelerometry, android, apnea patients, app, association, biomedical signal processing, management, mhealth, monitoring, pathophysiology, pilot mhealth, questionnaire, sleep position, smartphone, supine position, time, Accelerometry, Android, App, Biomedical signal processing, Mhealth, Monitoring, Sleep position, Smart-phone, Smartphone, Tennis ball technique
Molina, BG, Valle, LJ, Casanovas, J, Lanzalaco, S, Pérez-Madrigal, MM, Turon, P, Armelin, E, Alemán, C, (2021). Plasma-Functionalized Isotactic Polypropylene Assembled with Conducting Polymers for Bacterial Quantification by NADH Sensing Advanced Healthcare Materials 10, 2100425
Rapid detection of bacterial presence on implantable medical devices is essential to prevent biofilm formation, which consists of densely packed bacteria colonies able to withstand antibiotic-mediated killing. In this work, a smart approach is presented to integrate electrochemical sensors for detecting bacterial infections in biomedical implants made of isotactic polypropylene (i-PP) using chemical assembly. The electrochemical detection is based on the capacity of conducting polymers (CPs) to detect extracellular nicotinamide adenine dinucleotide (NADH) released from cellular respiration of bacteria, which allows distinguishing prokaryotic from eukaryotic cells. Oxygen plasma-functionalized free-standing i-PP, coated with a layer (≈1.1 µm in thickness) of CP nanoparticles obtained by oxidative polymerization, is used as working electrode for the anodic polymerization of a second CP layer (≈8.2 µm in thickness), which provides very high electrochemical activity and stability. The resulting layered material, i-PP /CP , detects the electro-oxidation of NADH in physiological media with a sensitivity 417 µA cm and a detection limit up to 0.14 × 10 m, which is below the concentration of extracellular NADH found for bacterial cultures of biofilm-positive and biofilm-negative strains. f 2 −2 −3
JTD Keywords: bacteria respiration, bacteria sensors, biomedical implants, flexible sensors, poly(3,4-ethylenedioxythiophene), Bacteria respiration, Bacteria sensors, Biomedical implants, Flexible sensors, Poly(3,4-ethylenedioxythiophene)
Boschker, HTS, Cook, PLM, Polerecky, L, Eachambadi, RT, Lozano, H, Hidalgo-Martinez, S, Khalenkow, D, Spampinato, V, Claes, N, Kundu, P, Wang, D, Bals, S, Sand, KK, Cavezza, F, Hauffman, T, Bjerg, JT, Skirtach, AG, Kochan, K, McKee, M, Wood, B, Bedolla, D, Gianoncelli, A, Geerlings, NMJ, Van Gerven, N, Remaut, H, Geelhoed, JS, Millan-Solsona, R, Fumagalli, L, Nielsen, LP, Franquet, A, Manca, JV, Gomila, G, Meysman, FJR, (2021). Efficient long-range conduction in cable bacteria through nickel protein wires Nature Communications 12, 3996
Filamentous cable bacteria display long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on individual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating protein shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures. Filamentous cable bacteria conduct electrical currents over centimeter distances through fibers embedded in their cell envelope. Here, Boschker et al. show that the fibers consist of a conductive core containing nickel proteins that is surrounded by an insulating protein shell.
JTD Keywords: Bacteria (microorganisms), Bacterial protein, Bacterial proteins, Bacterium, Chemistry, Deltaproteobacteria, Electric conductivity, Electricity, Electron, Electron transport, Metabolism, Microscopy, Nanowires, Nickel, Physiology, Protein, Resonance raman, Spectroscopy, Transport electrons
Balakrishnan, H, Millan-Solsona, R, Checa, M, Fabregas, R, Fumagalli, L, Gomila, G, (2021). Depth mapping of metallic nanowire polymer nanocomposites by scanning dielectric microscopy Nanoscale 13, 10116-10126
Polymer nanocomposite materials based on metallic nanowires are widely investigated as transparent and flexible electrodes or as stretchable conductors and dielectrics for biosensing. Here we show that Scanning Dielectric Microscopy (SDM) can map the depth distribution of metallic nanowires within the nanocomposites in a non-destructive way. This is achieved by a quantitative analysis of sub-surface electrostatic force microscopy measurements with finite-element numerical calculations. As an application we determined the three-dimensional spatial distribution of ?50 nm diameter silver nanowires in ?100 nm-250 nm thick gelatin films. The characterization is done both under dry ambient conditions, where gelatin shows a relatively low dielectric constant, ?r ? 5, and under humid ambient conditions, where its dielectric constant increases up to ?r ? 14. The present results show that SDM can be a valuable non-destructive subsurface characterization technique for nanowire-based nanocomposite materials, which can contribute to the optimization of these materials for applications in fields such as wearable electronics, solar cell technologies or printable electronics. © The Royal Society of Chemistry.
JTD Keywords: composite, constant, electrodes, mode, nanostructures, objects, progress, subsurface, tomography, Composite materials, Dielectric materials, Electric force microscopy, Electrostatic force, Force microscopy, Low dielectric constants, Nanocomposites, Numerical calculation, Polymer nanocomposite, Printable electronics, Scanning dielectric microscopy, Silver nanowires, Solar cell technology, Stretchable conductors, Subsurface characterizations, Transparent electrodes, Wearable technology
Covington, JA, Marco, S, Persaud, KC, Schiffman, SS, Nagle, HT, (2021). Artificial Olfaction in the 21st Century IEEE SENSORS JOURNAL 21, 12969-12990
The human olfactory system remains one of the most challenging biological systems to replicate. Humans use it without thinking, where it can equally offer protection from harm and bring enjoyment in equal measure. It is the system’s ability to detect and analyze complex odors, without the need for specialized infra-structure, that is the envy of many scientists. The field of artificial olfaction has recruited and stimulated interdisciplinary research and commercial development for several applications that include malodor measurement, medical diagnostics, food and beverage quality, environment and security. Over the last century, innovative engineers and scientists have been focused on solving a range of problems associated with measurement and control of odor. The IEEE Sensors Journal has published Special Issues on olfaction in 2002 and 2012. Here we continue that coverage. In this article, we summarize early work in the 20th Century that served as the foundation upon which we have been building our odor-monitoring instrumental and measurement systems. We then examine the current state of the art that has been achieved over the last two decades as we have transitioned into the 21st Century. Much has been accomplished, but great progress is needed in sensor technology, system design, product manufacture and performance standards. In the final section, we predict levels of performance and ubiquitous applications that will be realized during in the mid to late 21st Century.
JTD Keywords: air-quality, breath analysis, calibration transfer, chemical sensor arrays, chemosensor arrays, drift compensation, electronic nose, gas sensors, headspace sampling, machine learning, machine olfaction, odor detection, plume structure, voc analysis, Artificial olfaction, Electrodes, Electronic nose, Electronic nose technology, Headspace sampling, Instruments, Machine learning, Machine olfaction, Monitoring, Odor detection, Olfactory, Sensor phenomena and characterization, Sensors, Temperature sensors, Voc analysis
Torp, N, Israelsen, M, Madsen, B, Lutz, P, Jansen, C, Strassburg, C, Mortensen, C, Knudsen, AW, Sorensen, GL, Holmskov, U, Schlosser, A, Thiele, M, Trebicka, J, Krag, A, (2021). Level of MFAP4 in ascites independently predicts 1-year transplant-free survival in patients with cirrhosis JHEP Reports 3, 100287
Background & Aims: Prognostic models of cirrhosis underestimate disease severity for patients with cirrhosis and ascites. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein linked to hepatic neoangiogenesis and fibrogenesis. We investigated ascites MFAP4 as a predictor of transplant-free survival in patients with cirrhosis and ascites. Methods: A dual-centre observational study of patients with cirrhosis and ascites recruited consecutively in relation to a paracentesis was carried out. Patients were followed up for 1 year, until death or liver transplantation (LTx). Ascites MFAP4 was tested with the model for end-stage liver disease (MELD-Na), CLIF Consortium Acute Decompensation (CLIF-C AD), and Child-Pugh score in Cox regression models. Results: Ninety-three patients requiring paracentesis were included. Median ascites MFAP4 was 29.7 U/L [22.3–41.3], and MELD-Na was 19 [16–23]. A low MELD-Na score (<20) was observed in 49 patients (53%). During follow-up, 20 patients died (22%), and 6 received LTx (6%). High ascites MFAP4 (>29.7 U/L) was associated with 1-year transplant-free survival (p = 0.002). In Cox regression, ascites MFAP4 and MELD-Na independently predicted 1-year transplant-free survival (hazard ratio [HR] = 0.97, p = 0.03, and HR = 1.08, p = 0.01, respectively). Ascites MFAP4 and CLIF-C AD also predicted survival independently (HR = 0.96, p = 0.02, and HR = 1.05, p = 0.03, respectively), whereas only ascites MFAP4 did, controlling for the Child-Pugh score (HR = 0.97, p = 0.03, and HR = 1.18, p = 0.16, respectively). For patients with MELD-Na <20, ascites MFAP4 but not ascites protein predicted 1-year transplant-free survival (HR 0.91, p = 0.02, and HR = 0.94, p = 0.17, respectively). Conclusions: Ascites MFAP4 predicts 1-year transplant-free survival in patients with cirrhosis and ascites. In patients with low MELD-Na scores, ascites MFAP4, but not total ascites protein, significantly predicted 1-year transplant-free survival. Lay summary: Patients with cirrhosis who have fluid in the abdomen, ascites, are at an increased risk of death and in need for liver transplantation. Our study identified patients with ascites and a poor prognosis by measuring microfibrillar associated protein 4 (MFAP4), a protein present in the abdominal fluid. Patients with low levels of the MFAP4 protein are at particularly increased risk of death or liver transplantation, suggesting that clinical care should be intensified in this group of patients. © 2021 The Authors
JTD Keywords: biomarker, clif-c ad, clif consortium acute decompensation, cps, child-pugh score, crp, c-reactive protein, ct, computed tomography, decompensated, ecm, extracellular matrix, fibrosis, fluid protein, gfr, glomerular filtration rate, hr, hazard ratio, inr, internationalised normal ratio, liver disease, liver-cirrhosis, ltx, liver transplantation, markers, meld-na, model for end-stage liver disease, mfap4, microfibrillar associated protein 4, mortality, nash, non-alcoholic steatohepatitis, natural-history, prognosis, risk-factors, sbp, spontaneous bacterial peritonitis, scores, stage, Biomarker, Decompensated, Egfr, estimated gfr, Fibrosis, Liver disease, Mortality, Prognosis, Spontaneous bacterial peritonitis
Minguela, J, Muller, DW, Mucklich, F, Llanes, L, Ginebra, MP, Roa, JJ, Mas-Moruno, C, (2021). Peptidic biofunctionalization of laser patterned dental zirconia: A biochemical-topographical approach Materials Science & Engineering C-Materials for Biological Applications 125, 112096
A dual approach employing peptidic biofunctionalization and laser micro-patterns on dental zirconia was explored, with the aim of providing a flexible tool to improve tissue integration of restorations. Direct laser interference patterning with a femtosecond Ti:Sapphire laser was employed, and two periodic grooved patterns were produced with a periodicity of 3 and 10 μm. A platform containing the cell-adhesive RGD and the osteogenic DWIVA peptides was used to functionalize the grooved surfaces. Topography and surface damage were characterized by confocal laser scanning (CLSM), scanning electron and scanning transmission electron microscopy techniques. The surface patterns exhibited a high homogeneity and subsurface damage was found in the form of nano-cracks and nano-pores, at the bottom of the valleys. Accelerated tests in water steam were carried out to assess hydrothermal degradation resistance, which slightly decreased after the laser treatment. Interestingly, the detrimental effects of the laser modification were reverted by a post-laser thermal treatment. The attachment of the molecule was verified trough fluorescence CLSM and X-ray photoelectron spectroscopy. Finally, the biological properties of the surfaces were studied in human mesenchymal stem cells. Cell adhesion, morphology, migration and differentiation were investigated. Cells on grooved surfaces displayed an elongated morphology and aligned along the patterns. On these surfaces, migration was greatly enhanced along the grooves, but also highly restricted in the perpendicular direction as compared to flat specimens. After biofunctionalization, cell number and cell area increased and well-developed cell cytoskeletons were observed. However, no effects on cell migration were found for the peptidic platform. Although some osteogenic potential was found in specimens grooved with a periodicity of 10 μm, the largest effects were observed from the biomolecule, which favored upregulation of several genes related to osteoblastic differentiation in all the surfaces.
JTD Keywords: alumina toughened zirconia, cell alignment, grain-size, implants, interference, laser patterning, osteogenic differentiation, osteointegration, peptides, surface functionalization, surface-topography, tissue, titanium surface, Laser patterning, Low-temperature degradation, Osteointegration, Peptides, Surface functionalization, Zirconia
Ferrer-Lluis, I, Castillo-Escario, Y, Montserrat, JM, Jané, R, (2021). Enhanced monitoring of sleep position in sleep apnea patients: Smartphone triaxial accelerometry compared with video-validated position from polysomnography SENSORS 21, 3689
Poor sleep quality is a risk factor for multiple mental, cardiovascular, and cerebrovascular diseases. Certain sleep positions or excessive position changes can be related to some diseases and poor sleep quality. Nevertheless, sleep position is usually classified into four discrete values: supine, prone, left and right. An increase in sleep position resolution is necessary to better assess sleep position dynamics and to interpret more accurately intermediate sleep positions. This research aims to study the feasibility of smartphones as sleep position monitors by (1) developing algorithms to retrieve the sleep position angle from smartphone accelerometry; (2) monitoring the sleep position angle in patients with obstructive sleep apnea (OSA); (3) comparing the discretized sleep angle versus the four classic sleep positions obtained by the video-validated polysomnography (PSG); and (4) analyzing the presence of positional OSA (pOSA) related to its sleep angle of occurrence. Results from 19 OSA patients reveal that a higher resolution sleep position would help to better diagnose and treat patients with position-dependent diseases such as pOSA. They also show that smartphones are promising mHealth tools for enhanced position monitoring at hospitals and home, as they can provide sleep position with higher resolution than the gold-standard video-validated PSG.
JTD Keywords: accelerometry, actigraphy, association, biomedical signal processing, index, latency, mhealth, monitoring, pathophysiology, quality, questionnaire, score, sleep apnea, sleep position, smartphone, time, Accelerometry, Biomedical signal processing, Mhealth, Monitoring, Sleep apnea, Sleep position, Smartphone, Supine position
Oliveira, LVF, Apostólico, N, Uriarte, JJ, da Palma, RK, Prates, RA, Deana, AM, Ferreira, LR, Afonso, JPR, Vieira, RD, de Oliveira, MC Jr, Navajas, D, Farré, R, Lopes-Martins, RAB, (2021). Photodynamic Therapy in the Extracellular Matrix of Mouse Lungs: Preliminary Results of an Alternative Tissue Sterilization Process INTERNATIONAL JOURNAL OF PHOTOENERGY 2021, 5578387
Lung transplantation is one of the most difficult and delicate procedures among organ transplants. For the success of the procedure and survival of the new organ, the sterilization step for acellular lungs prior to recellularization is important to ensure that they are free of any risk of transmitting infections from the donor to the recipient subject. However, there are no available information concerning the lung mechanical parameters after sterilizing photodynamic therapy. The aim of this study was to evaluate the extracellular matrix (ECM) and lung mechanical parameters of decellularized lungs undergoing sterilizing photodynamic therapy (PDT). Besides, we also analyzed the lung after controlled infection with C. albicans in order to evaluate the effectiveness of PDT. The lung mechanical evaluation parameters, resistance (RL) and elastance (EL), exhibited no significant differences between groups. In addition, there were no PDT-induced changes in lung properties, with maintenance of the viscoelastic behavior of the lung scaffold after 1 h exposure to PDT. The ECM components remained virtually unchanged in the acellular lungs of both groups. We also showed that there was a reduction in fungal infection population after 45 minutes of PDT. However, more studies should be performed to establish and verify the effectiveness of PDT as a possible means for sterilizing lung scaffolds. This manuscript was presented as a master thesis of Nadua Apostólico at the postgraduate program in rehabilitation sciences, University Nove de Julho - UNINOVE.
JTD Keywords: candida, combination, inactivation, infections, mechanics, Gamma-irradiation
Burgués, J, Esclapez, MD, Doñate, S, Pastor, L, Marco, S, (2021). Aerial mapping of odorous gases in a wastewater treatment plant using a small drone Remote Sensing 13, 1757
Wastewater treatment plants (WWTPs) are sources of greenhouse gases, hazardous air pollutants and offensive odors. These emissions can have negative repercussions in and around the plant, degrading the quality of life of surrounding neighborhoods, damaging the environment, and reducing employee’s overall job satisfaction. Current monitoring methodologies based on fixed gas detectors and sporadic olfactometric measurements (human panels) do not allow for an accurate spatial representation of such emissions. In this paper we use a small drone equipped with an array of electrochemical and metal oxide (MOX) sensors for mapping odorous gases in a mid-sized WWTP. An innovative sampling system based on two (10 m long) flexible tubes hanging from the drone allowed near-source sampling from a safe distance with negligible influence from the downwash of the drone’s propellers. The proposed platform is very convenient for monitoring hard-toreach emission sources, such as the plant’s deodorization chimney, which turned out to be responsible for the strongest odor emissions. The geo-localized measurements visualized in the form of a two-dimensional (2D) gas concentration map revealed the main emission hotspots where abatement solutions were needed. A principal component analysis (PCA) of the multivariate sensor signals suggests that the proposed system can also be used to trace which emission source is responsible for a certain measurement.
JTD Keywords: air pollution, environmental monitoring, gas sensors, industrial emissions, mapping, odour, uav, Air pollution, Drone, Environmental monitoring, Gas sensors, Industrial emissions, Mapping, Odour, Sensors, Uav
Guix, M, Mestre, R, Patiño, T, De Corato, M, Fuentes, J, Zarpellon, G, Sánchez, S, (2021). Biohybrid soft robots with self-stimulating skeletons Science Robotics 6, eabe7577
Bioinspired hybrid soft robots that combine living and synthetic components are an emerging field in the development of advanced actuators and other robotic platforms (i.e., swimmers, crawlers, and walkers). The integration of biological components offers unique characteristics that artificial materials cannot precisely replicate, such as adaptability and response to external stimuli. Here, we present a skeletal muscle–based swimming biobot with a three-dimensional (3D)–printed serpentine spring skeleton that provides mechanical integrity and self-stimulation during the cell maturation process. The restoring force inherent to the spring system allows a dynamic skeleton compliance upon spontaneous muscle contraction, leading to a cyclic mechanical stimulation process that improves the muscle force output without external stimuli. Optimization of the 3D-printed skeletons is carried out by studying the geometrical stiffnesses of different designs via finite element analysis. Upon electrical actuation of the muscle tissue, two types of motion mechanisms are experimentally observed: directional swimming when the biobot is at the liquid-air interface and coasting motion when it is near the bottom surface. The integrated compliant skeleton provides both the mechanical self-stimulation and the required asymmetry for directional motion, displaying its maximum velocity at 5 hertz (800 micrometers per second, 3 body lengths per second). This skeletal muscle–based biohybrid swimmer attains speeds comparable with those of cardiac-based biohybrid robots and outperforms other muscle-based swimmers. The integration of serpentine-like structures in hybrid robotic systems allows self-stimulation processes that could lead to higher force outputs in current and future biomimetic robotic platforms. Copyright © 2021 The Authors, some rights reserved;
JTD Keywords: actuators, design, fabrication, mechanics, mems, myotubes, platform, tissue, 3d printers, Agricultural robots, Animals, Artificial organs, Biological components, Biomimetic materials, Biomimetic processes, Biomimetics, Cell line, Electrical actuation, Equipment design, Finite element analysis, Geometrical stiffness, Intelligent robots, Liquefied gases, Liquid-air interface, Mechanical integrity, Mechanical phenomena, Mechanical stimulation, Mice, Motion, Muscle, Muscle contractions, Muscle, skeletal, Phase interfaces, Printing, three-dimensional, Robotics, Serpentine, Smart materials, Springs (components), Swimming, Threedimensional (3-d), Tissue scaffolds
Blaya, D, Pose, E, Coll, M, Lozano, JJ, Graupera, I, Schierwagen, R, Jansen, C, Castro, P, Fernandez, S, Sidorova, J, Vasa-Nicotera, M, Sola, E, Caballeria, J, Trebicka, J, Gines, P, Sancho-Bru, P, (2021). Profiling circulating microRNAs in patients with cirrhosis and acute-on-chronic liver failure JHEP Reports 3, 100233
Background & Aims: MicroRNAs (miRNAs) circulate in several body fluids and can be useful biomarkers. The aim of this study was to identify blood-circulating miRNAs associated with cirrhosis progression and acute-on-chronic liver failure (ACLF). Methods: Using high-throughput screening of 754 miRNAs, serum samples from 45 patients with compensated cirrhosis, decompensated cirrhosis, or ACLF were compared with those from healthy individuals (n = 15). miRNA levels were correlated with clinical parameters, organ failure, and disease progression and outcome. Dysregulated miRNAs were evaluated in portal and hepatic vein samples (n = 33), liver tissues (n = 17), and peripheral blood mononuclear cells (PBMCs) (n = 16). Results: miRNA screening analysis revealed that circulating miRNAs are dysregulated in cirrhosis progression, with 51 miRNAs being differentially expressed among all groups of patients. Unsupervised clustering and principal component analysis indicated that the main differences in miRNA expression occurred at decompensation, showing similar levels in patients with decompensated cirrhosis and those with ACLF. Of 43 selected miRNAs examined for differences among groups, 10 were differentially expressed according to disease progression. Moreover, 20 circulating miRNAs were correlated with model for end-stage liver disease and Child-Pugh scores. Notably, 11 dysregulated miRNAs were associated with kidney or liver failure, encephalopathy, bacterial infection, and poor outcomes. The most severely dysregulated miRNAs (i.e. miR-146a5p, miR-26a-5p, and miR-191-5p) were further evaluated in portal and hepatic vein blood and liver tissue, but showed no differences. However, PBMCs from patients with cirrhosis showed significant downregulation of miR-26 and miR-146a, suggesting a extrahepatic origin of some circulating miRNAs. Conclusions: This study is a repository of circulating miRNA data following cirrhosis progression and ACLF. Circulating miRNAs were profoundly dysregulated during the progression of chronic liver disease, were associated with failure of several organs and could have prognostic utility. Lay summary: Circulating miRNAs are small molecules in the blood that can be used to identify or predict a clinical condition. Our study aimed to identify miRNAs for use as biomarkers in patients with cirrhosis or acute-on-chronic liver failure. Several miRNAs were found to be dysregulated during the progression of disease, and some were also related to organ failure and disease-related outcomes. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of European Association for the Study of the Liver (EASL).
JTD Keywords: aclf, acute-on-chronic liver failure, alt, alanine aminotransferase, ast, aspartate aminotransferase, biomarkers, chronic liver disease, cxcl10, c-x-c motif chemokine ligand 10, ef clif, european foundation for the study of chronic liver failure, foxo, forkhead box o, inr, international normalised ratio, ldh, lactate dehydrogenase, liver decompensation, mapk, mitogen-activated protein kinase, meld, model for end-stage liver disease, nash, non-alcoholic steatohepatitis, non-coding rnas, pbmcs, peripheral blood mononuclear cells, pca, principal component analysis, tgf, transforming growth factor, tips, transjugular intrahepatic portosystemic shunt, Biomarkers, Chronic liver disease, Expression, Liver decompensation, Markers, Mir-146a, Non-coding rnas, Qpcr, quantitative pcr
Avalos-Padilla, Y, Georgiev, VN, Lantero, E, Pujals, S, Verhoef, R, Borgheti-Cardoso, LN, Albertazzi, L, Dimova, R, Fernàndez-Busquets, X, (2021). The ESCRT-III machinery participates in the production of extracellular vesicles and protein export during Plasmodium falciparum infection PLoS Pathogens 17, e1009455-e1009455
Infection with Plasmodium falciparum enhances extracellular vesicle (EV) production in parasitized red blood cells (pRBCs), an important mechanism for parasite-to-parasite communication during the asexual intraerythrocytic life cycle. The endosomal sorting complex required for transport (ESCRT), and in particular the ESCRT-III sub-complex, participates in the formation of EVs in higher eukaryotes. However, RBCs have lost the majority of their organelles through the maturation process, including an important reduction in their vesicular network. Therefore, the mechanism of EV production in P. falciparum-infected RBCs remains to be elucidated. Here we demonstrate that P. falciparum possesses a functional ESCRT-III machinery activated by an alternative recruitment pathway involving the action of PfBro1 and PfVps32/PfVps60 proteins. Additionally, multivesicular body formation and membrane shedding, both reported mechanisms of EV production, were reconstituted in the membrane model of giant unilamellar vesicles using the purified recombinant proteins. Moreover, the presence of PfVps32, PfVps60 and PfBro1 in EVs purified from a pRBC culture was confirmed by super-resolution microscopy and dot blot assays. Finally, disruption of the PfVps60 gene led to a reduction in the number of the produced EVs in the KO strain and affected the distribution of other ESCRT-III components. Overall, our results increase the knowledge on the underlying molecular mechanisms during malaria pathogenesis and demonstrate that ESCRT-III P. falciparum proteins participate in EV production.
JTD Keywords: Endosomal sorting complexes required for transport, Erythrocytes, Extracellular vesicles, Humans, Malaria, falciparum, Plasmodium falciparum, Protein domains, Protein transport, Responsible consumption and production
Pieper, CC, Feisst, A, Meyer, C, Luetkens, J, Praktiknjo, M, Trebicka, J, Attenberger, U, Jansen, C, (2021). Impact of transjugular intrahepatic portosystemic shunt creation on the central lymphatic system in liver cirrhosis Scientific Reports 11, 7065
The puropse of this study was to evaluate associations of cisterna chyli (CCh) diameter with portal hemodynamics and the influence of TIPS-creation in cirrhotic patients. 93 cirrhotic patients (57 male, mean age 59 years) received CT prior to TIPS-creation. 38/93 additionally underwent post-interventional CT. CCh-diameter was measured. After categorization into patients with and without large venous collaterals (i.e. > 6 mm), data were analyzed regarding associations between CCh-diameter, clinical and portal-hemodynamic parameters and diameter-changes after TIPS-creation. Patient survival post-TIPS was analyzed. Median portosystemic pressure-gradient decreased from 20 to 9 mmHg after TIPS-creation. Large venous collaterals were observed in 59 patients. In 69/93 patients (74.2%) the CCh was detectable. Mean pre-interventional diameter was 9.4 ± 2.7 mm (large collaterals: 8.7 ± 2.0 mm, no large collaterals: 10.7 ± 3.2 mm, p = 0.003). CCh-diameter correlated strongly with pre-TIPS portal-pressure (Rs = 0.685, p = 0.0001), moderately with portosystemic-gradient (Rs = 0.524, p = 0.006), liver shear-wave-elastography (Rs = 0.597, p = 0.004) and spleen size (Rs = 0.501, p = 0.01) in patients without large collaterals, but not in patients with large collaterals. Post-TIPS CCh-diameter decreased significantly from 10.2 ± 2.8 mm to 8.3 ± 3.0 mm (p < 0.001). Patients without a detectable CCh on CT survived significantly shorter. The diameter of the CCh is associated with portal-pressure and decreases after TIPS-creation in cirrhotic patients, reflecting a portal decompression mechanism via the lymphatic system. Lack of larger central lymphatics detectable on CT may be associated with shorter survival.
JTD Keywords: circulation, cisterna chyli, fluid, hepatic cirrhosis, shear-wave elastography, thoracic-duct, vessels, Significant portal-hypertension
Arista-Romero, M, Pujals, S, Albertazzi, L, (2021). Towards a Quantitative Single Particle Characterization by Super Resolution Microscopy: From Virus Structures to Antivirals Design Frontiers in Bioengineering and Biotechnology 9, 647874
In the last year the COVID19 pandemic clearly illustrated the potential threat that viruses pose to our society. The characterization of viral structures and the identification of key proteins involved in each step of the cycle of infection are crucial to develop treatments. However, the small size of viruses, invisible under conventional fluorescence microscopy, make it difficult to study the organization of protein clusters within the viral particle. The applications of super-resolution microscopy have skyrocketed in the last years, converting this group into one of the leading techniques to characterize viruses and study the viral infection in cells, breaking the diffraction limit by achieving resolutions up to 10 nm using conventional probes such as fluorescent dyes and proteins. There are several super-resolution methods available and the selection of the right one it is crucial to study in detail all the steps involved in the viral infection, quantifying and creating models of infection for relevant viruses such as HIV-1, Influenza, herpesvirus or SARS-CoV-1. Here we review the use of super-resolution microscopy (SRM) to study all steps involved in the viral infection and antiviral design. In light of the threat of new viruses, these studies could inspire future assays to unveil the viral mechanism of emerging viruses and further develop successful antivirals against them.
JTD Keywords: antivirals, characterization, imaging, super-resolution, virus, Antivirals, Characterization, Imaging, Super-resolution, Virus
Garcia, J, Fernández-Pradas, JM, Lladó, A, Serra, P, Zalvidea, D, Kogan, MJ, Giralt, E, Sánchez-Navarro, M, (2021). The combined use of gold nanoparticles and infrared radiation enables cytosolic protein delivery CHEMISTRY-A EUROPEAN JOURNAL 27, 4670-4675
© 2020 Wiley-VCH GmbH Cytosolic protein delivery remains elusive. The inability of most proteins to cross the cellular membrane is a huge hurdle. Here we explore the unique photothermal properties of gold nanorods (AuNRs) to trigger cytosolic delivery of proteins. Both partners, protein and AuNRs, are modified with a protease-resistant cell-penetrating peptide with nuclear targeting properties to induce internalization. Once internalized, spatiotemporal control of protein release is achieved by near-infrared laser irradiation in the safe second biological window. Importantly, catalytic amounts of AuNRs are sufficient to trigger cytosolic protein delivery. To the best of our knowledge, this is the first time that AuNRs with their maximum of absorption in the second biological window are used to deliver proteins into the intracellular space. This strategy represents a powerful tool for the cytosolic delivery of virtually any class of protein.
JTD Keywords: cell-penetrating peptide, cytosolic delivery, gold nanorod, near-infrared irradiation, Cell line, tumor, Cell-penetrating peptide, Cytosolic delivery, Gold, Gold nanorod, Metal nanoparticles, Nanotubes, Near-infrared irradiation, Phototherapy
Estrada-Petrocelli, L, Torres, A, Sarlabous, L, Rafols-de-Urquia, M, Ye-Lin, Y, Prats-Boluda, G, Jane, R, Garcia-Casado, J, (2021). Evaluation of Respiratory Muscle Activity by Means of Concentric Ring Electrodes IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING 68, 1005-1014
© 1964-2012 IEEE. Surface electromyography (sEMG) can be used for the evaluation of respiratory muscle activity. Recording sEMG involves the use of surface electrodes in a bipolar configuration. However, electrocardiographic (ECG) interference and electrode orientation represent considerable drawbacks to bipolar acquisition. As an alternative, concentric ring electrodes (CREs) can be used for sEMG acquisition and offer great potential for the evaluation of respiratory muscle activity due to their enhanced spatial resolution and simple placement protocol, which does not depend on muscle fiber orientation. The aim of this work was to analyze the performance of CREs during respiratory sEMG acquisitions. Respiratory muscle sEMG was applied to the diaphragm and sternocleidomastoid muscles using a bipolar and a CRE configuration. Thirty-two subjects underwent four inspiratory load spontaneous breathing tests which was repeated after interchanging the electrode positions. We calculated parameters such as (1) spectral power and (2) median frequency during inspiration, and power ratios of inspiratory sEMG without ECG in relation to (3) basal sEMG without ECG (Rins/noise), (4) basal sEMG with ECG (Rins/cardio) and (5) expiratory sEMG without ECG (Rins/exp). Spectral power, Rins/noise and Rins/cardio increased with the inspiratory load. Significantly higher values (p < 0.05) of Rins/cardio and significantly higher median frequencies were obtained for CREs. Rins/noise and Rins/exp were higher for the bipolar configuration only in diaphragm sEMG recordings, whereas no significant differences were found in the sternocleidomastoid recordings. Our results suggest that the evaluation of respiratory muscle activity by means of sEMG can benefit from the remarkably reduced influence of cardiac activity, the enhanced detection of the shift in frequency content and the axial isotropy of CREs which facilitates its placement.
JTD Keywords: atmospheric measurements, concentric ring electrodes, electrocardiography, electrodes, electromyography, laplacian potential, non-invasive respiratory monitoring, particle measurements, respiratory muscles, surface electromyography, Concentric ring electrodes, Diaphragm, Electrocardiography, Electrodes, Electromyography, Humans, Laplacian potential, Muscle, skeletal, Muscles, Non-invasive respiratory monitoring, Respiratory muscles, Surface electromyography
Lozano-García, M, Estrada-Petrocelli, L, Torres, A, Rafferty, GF, Moxham, J, Jolley, CJ, Jané, R, (2021). Noninvasive assessment of neuromechanical coupling and mechanical efficiency of parasternal intercostal muscle during inspiratory threshold loading SENSORS 21, 1781
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This study aims to investigate noninvasive indices of neuromechanical coupling (NMC) and mechanical efficiency (MEff) of parasternal intercostal muscles. Gold standard assessment of diaphragm NMC requires using invasive techniques, limiting the utility of this procedure. Nonin-vasive NMC indices of parasternal intercostal muscles can be calculated using surface mechano-myography (sMMGpara) and electromyography (sEMGpara). However, the use of sMMGpara as an in-spiratory muscle mechanical output measure, and the relationships between sMMGpara, sEMGpara, and simultaneous invasive and noninvasive pressure measurements have not previously been eval-uated. sEMGpara, sMMGpara, and both invasive and noninvasive measurements of pressures were recorded in twelve healthy subjects during an inspiratory loading protocol. The ratios of sMMGpara to sEMGpara, which provided muscle-specific noninvasive NMC indices of parasternal intercostal muscles, showed nonsignificant changes with increasing load, since the relationships between sMMGpara and sEMGpara were linear (R2 = 0.85 (0.75–0.9)). The ratios of mouth pressure (Pmo) to sEMGpara and sMMGpara were also proposed as noninvasive indices of parasternal intercostal muscle NMC and MEff, respectively. These indices, similar to the analogous indices calculated using invasive transdiaphragmatic and esophageal pressures, showed nonsignificant changes during threshold loading, since the relationships between Pmo and both sEMGpara (R2 = 0.84 (0.77–0.93)) and sMMGpara (R2 = 0.89 (0.85–0.91)) were linear. The proposed noninvasive NMC and MEff indices of parasternal intercostal muscles may be of potential clinical value, particularly for the regular assessment of patients with disordered respiratory mechanics using noninvasive wearable and wireless devices.
JTD Keywords: inspiratory threshold loading, neuromechanical coupling, parasternal intercostal muscles, respiratory pressure, surface electromyography, surface mechanomyography, Inspiratory threshold loading, Neuromechanical coupling, Parasternal intercostal mus-cles, Respiratory pressure, Surface electromyography, Surface mechanomyography
Hodásová, L, Sans, J, Molina, BG, Alemán, C, Llanes, L, Fargas, G, Armelin, E, (2021). Polymer infiltrated ceramic networks with biocompatible adhesive and 3D-printed highly porous scaffolds Additive Manufacturing 39, 101850
© 2021 Elsevier B.V. Herein, for the first time is described the design of a novel porous zirconia scaffolds manufactured by using polymer-infiltrated ceramic network (PICN) and 3D-printing technologies. Cubic geometry of pieces was obtained by perpendicular layer-by-layer deposition of yttrium-stabilized tetragonal zirconia polycrystal (3Y-TZP) and Pluronic® hydrogel ceramic paste. The specimens were prepared by robocasting assembly with 50% infill and 50% of pores, as feed setup. Bisphenol A glycerolate dimethacrylate (Bis-GMA) and tri(ethylenglycol) dimethacrylate (TEGDMA) copolymer, a well-known biocompatible adhesive, which is widely used in dentistry field, was employed to reinforce the pores of the 3D-printed ceramic structure. The success of the acrylate polymer infiltration above the scaffold surface and among the 3Y-TZP filaments was achieved through previous ceramic functionalization with 3-(trimethoxysilyl)propyl methacrylate (γ-MPS). The well infiltration of the material on pores was evaluated by gravimetry, obtaining a value of 87.5 ± 6.6% of pores covered by the adhesive. Such successful infiltration of methacrylate copolymer had also a positive effect on the mechanical properties of the scaffold material, being the PICN sample that one with the highest elongation resistance. The new system showed reduced bacteria proliferation, over 24 h of incubation with Gram-negative Escherichia coli and Gram-positive Streptococcus salivarius bacteria lines, when compared to the control.
JTD Keywords: acrylate polymer, bacteria colonization, yttrium stabilized zirconia, Acrylate polymer, Bacteria colonization, Robocasting, Yttrium stabilized zirconia
Ebrahimi, N, Bi, CH, Cappelleri, DJ, Ciuti, G, Conn, AT, Faivre, D, Habibi, N, Hosovsky, A, Iacovacci, V, Khalil, ISM, Magdanz, V, Misra, S, Pawashe, C, Rashidifar, R, Soto-Rodriguez, PED, Fekete, Z, Jafari, A, (2021). Magnetic Actuation Methods in Bio/Soft Robotics ADVANCED FUNCTIONAL MATERIALS 31, 2005137
© 2020 Wiley-VCH GmbH In recent years, magnetism has gained an enormous amount of interest among researchers for actuating different sizes and types of bio/soft robots, which can be via an electromagnetic-coil system, or a system of moving permanent magnets. Different actuation strategies are used in robots with magnetic actuation having a number of advantages in possible realization of microscale robots such as bioinspired microrobots, tetherless microrobots, cellular microrobots, or even normal size soft robots such as electromagnetic soft robots and medical robots. This review provides a summary of recent research in magnetically actuated bio/soft robots, discussing fabrication processes and actuation methods together with relevant applications in biomedical area and discusses future prospects of this way of actuation for possible improvements in performance of different types of bio/soft robots.
JTD Keywords: capsule endoscope, controlled propulsion, conventional gastroscopy, digital microfluidics, guided capsule, liquid-metal, magnetic drug delivery, magnetic microrobots, magnetically guided capsule endoscopy, magnetotactic bacteria, nanoscribe ip-dip, navigation system, Gallium-indium egain, Magnetic bioinspired micromanipulation, Magnetic drug delivery, Magnetic microrobots, Magnetically guided capsule endoscopy, Magnetotactic bacteria
Tornín, J, Villasante, A, Solé-Martí, X, Ginebra, MP, Canal, C, (2021). Osteosarcoma tissue-engineered model challenges oxidative stress therapy revealing promoted cancer stem cell properties FREE RADICAL BIOLOGY AND MEDICINE 164, 107-118
© 2020 The Author(s) The use of oxidative stress generated by Cold Atmospheric Plasma (CAP) in oncology is being recently studied as a novel potential anti-cancer therapy. However, the beneficial effects of CAP for treating osteosarcoma have mostly been demonstrated in 2-dimensional cultures of cells, which do not mimic the complexity of the 3-dimensional (3D) bone microenvironment. In order to evaluate the effects of CAP in a relevant context of the human disease, we developed a 3D tissue-engineered model of osteosarcoma using a bone-like scaffold made of collagen type I and hydroxyapatite nanoparticles. Human osteosarcoma cells cultured within the scaffold showed a high capacity to infiltrate and proliferate and to exhibit osteomimicry in vitro. As expected, we observed significantly different functional behaviors between monolayer and 3D cultures when treated with Cold Plasma-Activated Ringer's Solution (PAR). Our data reveal that the 3D environment not only protects cells from PAR-induced lethality by scavenging and diminishing the amount of reactive oxygen and nitrogen species generated by CAP, but also favours the stemness phenotype of osteosarcoma cells. This is the first study that demonstrates the negative effect of PAR on cancer stem-like cell subpopulations in a 3D biomimetic model of cancer. These findings will allow to suitably re-focus research on plasma-based therapies in future.
JTD Keywords: 3d tumor model, cancer stem-like cells, cold atmospheric plasma, osteosarcoma, oxidative stress, plasma activated liquids, reactive oxygen and nitrogen species, 3d tumor model, Bone neoplasms, Cancer stem-like cells, Cell line, tumor, Cold atmospheric plasma, Humans, Neoplastic stem cells, Osteosarcoma, Oxidative stress, Plasma activated liquids, Plasma gases, Reactive oxygen and nitrogen species, Tumor microenvironment
Moreira, VB, Puiggalí-Jou, A, Jiménez-Piqué, E, Alemán, C, Meneguzzi, A, Armelin, E, (2021). Green nanocoatings based on the deposition of zirconium oxide: The role of the substrate Materials 14, 1043
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. Herein, the influence of the substrate in the formation of zirconium oxide monolayer, from an aqueous hexafluorozirconic acid solution, by chemical conversion and by electro-assisted deposi-tion, has been approached. The nanoscale dimensions of the ZrO2 film is affected by the substrate nature and roughness. This study evidenced that the mechanism of Zr-EAD is dependent on the potential applied and on the substrate composition, whereas conversion coating is uniquely dependent on the adsorption reaction time. The zirconium oxide based nanofilms were more homogenous in AA2024 substrates if compared to pure Al grade (AA1100). It was justified by the high content of Cu alloying element present in the grain boundaries of the latter. Such intermetallic active sites favor the obtaining of ZrO2 films, as demonstrated by XPS and AFM results. From a mechanistic point of view, the electrochemical reactions take place simultaneously with the conventional chemical conversion process driven by ions diffusion. Such findings will bring new perspectives for the generation of controlled oxide coatings in modified electrodes used, as for example, in the construction of battery cells; in automotive and in aerospace industries, to replace micrometric layers of zinc phosphate by light-weight zirconium oxide nanometric ones. This study is particularly addressed for the reduction of industrial waste by applying green bath solutions without the need of auxiliary compounds and using lightweight ceramic materials.
JTD Keywords: aluminum alloys, conversion coating, electro-assisted deposition, metal-oxide interface, nanocoating, zirconium oxide, Aluminum alloys, Conversion coating, Electro-assisted deposition, Metal-oxide interface, Nanocoating, Zirconium oxide
Mateu-Sanz, M, Tornin, J, Ginebra, MP, Canal, C, (2021). Cold Atmospheric Plasma: A New Strategy Based Primarily on Oxidative Stress for Osteosarcoma Therapy Journal of Clinical Medicine 10, 893
Osteosarcoma is the most common primary bone tumor, and its first line of treatment presents a high failure rate. The 5-year survival for children and teenagers with osteosarcoma is 70% (if diagnosed before it has metastasized) or 20% (if spread at the time of diagnosis), stressing the need for novel therapies. Recently, cold atmospheric plasmas (ionized gases consisting of UV-Vis radiation, electromagnetic fields and a great variety of reactive species) and plasma-treated liquids have been shown to have the potential to selectively eliminate cancer cells in different tumors through an oxidative stress-dependent mechanism. In this work, we review the current state of the art in cold plasma therapy for osteosarcoma. Specifically, we emphasize the mechanisms unveiled thus far regarding the action of plasmas on osteosarcoma. Finally, we review current and potential future approaches, emphasizing the most critical challenges for the development of osteosarcoma therapies based on this emerging technique.
JTD Keywords: cancer stem cells, cold atmospheric plasma, osteosarcoma, oxidative stress, plasma treated liquids, reactive oxygen and nitrogen species, Antineoplastic activity, Antineoplastic agent, Cancer chemotherapy, Cancer stem cell, Cancer stem cells, Cancer surgery, Cancer survival, Cell therapy, Cold atmospheric plasma, Cold atmospheric plasma therapy, Electromagnetism, Human, In vitro study, Intracellular signaling, Oncogene, Osteosarcoma, Oxidative stress, Plasma treated liquids, Reactive nitrogen species, Reactive oxygen and nitrogen species, Reactive oxygen metabolite, Review, Tumor microenvironment
Pinheiro, ND, Freire, RT, Conrado, JAM, Batista, AD, Petruci, JFD, (2021). Paper-based optoelectronic nose for identification of indoor air pollution caused by 3D printing thermoplastic filaments ANALYTICA CHIMICA ACTA 1143, 1-8
Commercial printers based on fused deposition modeling (FDM) are widely adopted for 3D printing applications. This method consists of the heating of polymeric filaments over the melting point followed by their deposition onto a solid base to create the desirable 3D structure. Prior investigation using chromatographic techniques has shown that chemical compounds (e.g. VOCs), which can be harmful to users, are emitted during the printing process, producing adverse effects to human health and contributing to indoor air pollution. In this study, we present a simple, inexpensive and disposable paperbased optoelectronic nose (i.e. colorimetric sensor array) to identify the gaseous emission fingerprint of five different types of thermoplastic filaments (ABS, TPU, PETG, TRITAN and PLA) in the indoor environment. The optoelectronic nose is comprised of selected 15 dyes with different chemical properties deposited onto a microfluidic paper-based device with spots of 5 mm in diameter each. Digital images were obtained from an ordinary flatbed scanner, and the RGB information collected before and after air exposure was extracted by using an automated routine designed in MATLAB, in which the color changes provide a unique fingerprint for each filament in 5 min of printing. Reproducibility was obtained in the range of 2.5-10% (RSD). Hierarchical clustering analysis (HCA) and principal component analysis (PCA) were successfully employed, showing suitable discrimination of all studied filaments and the non-polluted air. Besides, air spiked with vapors of the most representative VOCs were analyzed by the optoelectronic nose and visually compared to each filament. The described study shows the potential of the paper-based optoelectronic nose to monitor possible hazard emissions from 3D printers. (C) 2020 Elsevier B.V. All rights reserved.
JTD Keywords: 3d printing, colorimetric sensor array, indoor air pollution, optoelectronic nose, paper-based, 3d printing, Colorimetric sensor array, Emissions, Indoor air pollution, Optoelectronic nose, Paper-based, Thermoplastic filaments
Blanco-Almazán, D, Groenendaal, W, Lozano-García, M, Estrada-Petrocelli, L, Lijnen, L, Smeets, C, Ruttens, D, Catthoor, F, Jané, R, (2021). Combining Bioimpedance and Myographic Signals for the Assessment of COPD during Loaded Breathing IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING 68, 298-307
© 1964-2012 IEEE. Chronic Obstructive Pulmonary Disease (COPD) is one of the most common chronic conditions. The current assessment of COPD requires a maximal maneuver during a spirometry test to quantify airflow limitations of patients. Other less invasive measurements such as thoracic bioimpedance and myographic signals have been studied as an alternative to classical methods as they provide information about respiration. Particularly, strong correlations have been shown between thoracic bioimpedance and respiratory volume. The main objective of this study is to investigate bioimpedance and its combination with myographic parameters in COPD patients to assess the applicability in respiratory disease monitoring. We measured bioimpedance, surface electromyography and surface mechanomyography in forty-three COPD patients during an incremental inspiratory threshold loading protocol. We introduced two novel features that can be used to assess COPD condition derived from the variation of bioimpedance and the electrical and mechanical activity during each respiratory cycle. These features demonstrate significant differences between mild and severe patients, indicating a lower inspiratory contribution of the inspiratory muscles to global respiratory ventilation in the severest COPD patients. In conclusion, the combination of bioimpedance and myographic signals provides useful indices to noninvasively assess the breathing of COPD patients.
JTD Keywords: Bioimpedance, Chronic obstructive pulmonary disease, Inspiratory threshold protocol, Myographic signals, Wearables
Watt, AC, Cejas, P, DeCristo, MJ, Metzger, O, Lam, EYN, Qiu, XT, BrinJones, H, Kesten, N, Coulson, R, Font-Tello, A, Lim, K, Vadhi, R, Daniels, VW, Montero, J, Taing, L, Meyer, CA, Gilan, O, Bell, CC, Korthauer, KD, Giambartolomei, C, Pasaniuc, B, Seo, JH, Freedman, ML, Ma, CT, Ellis, MJ, Krop, I, Winer, E, Letai, A, Brown, M, Dawson, MA, Long, HW, Zhao, JJ, Goel, S, (2021). CDK4/6 inhibition reprograms the breast cancer enhancer landscape by stimulating AP-1 transcriptional activity Nature Cancer 2, 34-48
Goel and colleagues show that CDK4/6 inhibition induces global chromatin changes mediated by AP-1 factors, which mediate key biological and clinical effects in breast cancer. Pharmacologic inhibitors of cyclin-dependent kinases 4 and 6 (CDK4/6) were designed to induce cancer cell cycle arrest. Recent studies have suggested that these agents also exert other effects, influencing cancer cell immunogenicity, apoptotic responses and differentiation. Using cell-based and mouse models of breast cancer together with clinical specimens, we show that CDK4/6 inhibitors induce remodeling of cancer cell chromatin characterized by widespread enhancer activation, and that this explains many of these effects. The newly activated enhancers include classical super-enhancers that drive luminal differentiation and apoptotic evasion, as well as a set of enhancers overlying endogenous retroviral elements that are enriched for proximity to interferon-driven genes. Mechanistically, CDK4/6 inhibition increases the level of several activator protein-1 transcription factor proteins, which are in turn implicated in the activity of many of the new enhancers. Our findings offer insights into CDK4/6 pathway biology and should inform the future development of CDK4/6 inhibitors.
JTD Keywords: Abemaciclib, Androgen receptor, Animal experiment, Animal model, Animal tissue, Apoptosis, Article, Breast cancer, C-jun, Cancer cell, Carcinoembryonic antigen related cell adhesion molecule 1, Caspase 3, Cell cycle arrest, Cells, Chromatin, Chromatin immunoprecipitation, Controlled study, Cyclin dependent kinase 4, Cyclin dependent kinase 6, Dna damage, Epidermal growth factor receptor 2, Estrogen receptor, Female, Flow cytometry, Fulvestrant, Hla drb1 antigen, Human, Human cell, Immunoblotting, Immunogenicity, Immunoprecipitation, Interferon, Luciferase assay, Mcf-7 cell line, Mda-mb-231 cell line, Microarray analysis, Morphogenesis, Mouse, Nonhuman, Palbociclib, Protein, Protein expression, Rb, Resistance, Rna polymerase ii, Rna sequence, Selective-inhibition, Senescence, Short tandem repeat, Signal transduction, Tamoxifen, Transcription elongation, Transcription factor, Transcription factor ap 1, Transcriptome, Tumor biopsy, Tumor differentiation, Tumor spheroid, Tumor xenograft, Vinculin, Whole exome sequencing
Costa, JD, Ballester, BR, Verschure, PFMJ, (2021). A Rehabilitation Wearable Device to Overcome Post-stroke Learned Non-use. Methodology, Design and Usability Communications in Computer and Information Science 1538, 198-205
After a stroke, a great number of patients experience persistent motor impairments such as hemiparesis or weakness in one entire side of the body. As a result, the lack of use of the paretic limb might be one of the main contributors to functional loss after clinical discharge. We aim to reverse this cycle by promoting the use of the paretic limb during activities of daily living (ADLs). To do so, we describe the key components of a system composed of a wearable bracelet (i.e., a smartwatch) and a mobile phone, designed to bring a set of neurorehabilitation principles that promote acquisition, retention and generalization of skills to the home of the patient. A fundamental question is whether the loss in motor function derived from learned–non–use may emerge as a consequence of decision–making processes for motor optimization. Our system is based on well-established rehabilitation strategies that aim to reverse this behaviour by increasing the reward associated with action execution and implicitly reducing the expected cost of using the paretic limb, following the notion of reinforcement–induced movement therapy (RIMT). Here we validate an accelerometer-based measure of arm use and its capacity to discriminate different activities that require increasing movement of the arm. The usability and acceptance of the device as a rehabilitation tool is tested using a battery of self–reported and objective measurements obtained from acute/subacute patients and healthy controls. We believe that an extension of these technologies will allow for the deployment of unsupervised rehabilitation paradigms during and beyond hospitalization time. © 2021, Springer Nature Switzerland AG.
JTD Keywords: adls, hemiparesis, learned non-use, wearables, Activities of daily living, Adls, Functional loss, Generalisation, Hemiparesis, Learned non-use, Motor impairments, Neurorehabilitation [], Patient experiences, Stroke, Wearable devices, Wearable technology, Wearables
Martí, D, Torras, J, Bertran, O, Turon, P, Alemán, C, (2021). Temperature effect on the SARS-CoV-2: A molecular dynamics study of the spike homotrimeric glycoprotein Computational and Structural Biotechnology Journal 19, 1848-1862
Rapid spread of SARS-CoV-2 virus have boosted the need of knowledge about inactivation mechanisms to minimize the impact of COVID-19 pandemic. Recent studies have shown that SARS-CoV-2 virus can be disabled by heating, the exposure time for total inactivation depending on the reached temperature (e.g. more than 45 min at 329 K or less than 5 min at 373 K. In spite of recent crystallographic structures, little is known about the molecular changes induced by the temperature. Here, we unravel the molecular basis of the effect of the temperature over the SARS-CoV-2 spike glycoprotein, which is a homotrimer with three identical monomers, by executing atomistic molecular dynamics (MD) simulations at 298, 310, 324, 338, 358 and 373 K. Furthermore, both the closed down and open up conformational states, which affect the accessibility of receptor binding domain, have been considered. Our results suggest that the spike homotrimer undergoes drastic changes in the topology of the hydrogen bonding interactions and important changes on the secondary structure of the receptor binding domain (RBD), while electrostatic interactions (i.e. salt bridges) are mainly preserved. The proposed inactivation mechanism has important implications for engineering new approaches to fight the SARS-CoV-2 coronavirus, as for example, cleaving or reorganizing the hydrogen bonds through chaotropic agents or nanoparticles with local surface resonant plasmon effect.
JTD Keywords: atomistic simulations, coronaviruses, denaturation, homotrimeric protein, inactivation, proteins, receptor binding domain, salt bridges, simulation, thermal inactivation, virus spike, Atomistic simulations, Homotrimeric protein, Receptor binding domain, Secondary-structure, Thermal inactivation, Virus spike
Marti, D, Martin-Martinez, E, Torras, J, Bertran, O, Turon, P, Aleman, C, (2021). In silico antibody engineering for SARS-CoV-2 detection Computational and Structural Biotechnology Journal 19, 5525-5534
Engineered immunoglobulin-G molecules (IgGs) are of wide interest for the development of detection elements in protein-based biosensors with clinical applications. The strategy usually employed for the de novo design of such engineered IgGs consists on merging fragments of the three-dimensional structure of a native IgG, which is immobilized on the biosensor surface, and of an antibody with an exquisite target specificity and affinity. In this work conventional and accelerated classical molecular dynamics (cMD and aMD, respectively) simulations have been used to propose two IgG-like antibodies for COVID-19 detection. More specifically, the crystal structure of the IgG1 B12 antibody, which inactivates the human immunodeficiency virus-1, has been merged with the structure of the antibody CR3022 Fab tightly bounded to SARS-CoV-2 receptor-binding domain (RBD) and the structure of the 5309 antibody Fab fragment complexed with SARS-CoV-2 RBD. The two constructed antibodies, named IgG1-CR3022 and IgG1-S309, respectively, have been immobilized on a stable gold surface through a linker. Analyses of the influence of both the merging strategy and the substrate on the stability of the two constructs indicate that the IgG1-S309 antibody better preserves the neutralizing structure than the IgG1-CR3022 one. Overall, results indicate that the IgG1-S309 is appropriated for the generation of antibody based sensors for COVID-19 diagnosis. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of Research Network of Computational and Structural Biotechnology.
JTD Keywords: cr3022, igg1, molecular engineering, s309, Antibodies, Antibody engineering, Biosensors, Chemical detection, Clinical application, Cov, Cr3022, Crystal structure, Design, Diseases, Gold nanoparticles, Igg1, Igg1 antibody, Immobilization, Immunoglobulin g, Immunosensor, In-silico, Merging, Molecular dynamics, Molecular engineering, Orientation, Protein-based biosensors, Receptor-binding domains, S309, Sars, Sensor, Spike protein, Target, Vaccine, Viruses
Blanco-Almazán, D, Groenendaal, W, Catthoor, F, Jané, R, (2021). Detection of Respiratory Phases to Estimate Breathing Pattern Parameters using Wearable Bioimpendace Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 2021, 5508-5511
Many studies have focused on novel noninvasive techniques to monitor respiratory rate such as bioimpedance. We propose an algorithm to detect respiratory phases using wearable bioimpedance to compute time parameters like respiratory rate, inspiratory and expiratory times, and duty cycle. The proposed algorithm was compared with two other algorithms from literature designed to estimate the respiratory rate using physiological signals like bioimpedance. We acquired bioimpedance and airflow from 50 chronic obstructive pulmonary disease (COPD) patients during an inspiratory loading protocol. We compared performance of the algorithms by computing accuracy and mean average percentage error (MAPE) between the bioimpedance parameters and the reference parameters from airflow. We found similar performance for the three algorithms in terms of accuracy (>0.96) and respiratory time and rate errors (<3.42 %). However, the proposed algorithm showed lower MAPE in duty cycle (10.18 %), inspiratory time (10.65 %) and expiratory time (8.61 %). Furthermore, only the proposed algorithm kept the statistical differences in duty cycle between COPD severity levels that were observed using airflow. Accordingly, we suggest bioimpedance to monitor breathing pattern parameters in home situations.Clinical relevance - This study exhibits the suitability of wearable thoracic bioimpedance to detect respiratory phases and to compute accurate breathing pattern parameters. © 2021 IEEE.
JTD Keywords: algorithms, copd, signals, Algorithm, Algorithms, Bioimpedance, Breathing rate, Chronic obstructive lung disease, Electronic device, Human, Humans, Lung, Pulmonary disease, chronic obstructive, Respiratory rate, Wearable electronic devices
Ben Hamouda, S, Vargas, A, Boivin, R, Miglino, MA, da Palma, RK, Lavoie, JP, (2021). Recellularization of Bronchial Extracellular Matrix With Primary Bronchial Smooth Muscle Cells JOURNAL OF EQUINE VETERINARY SCIENCE 96, 103313
© 2020 Elsevier Inc. Severe asthma is associated with an increased airway smooth muscle (ASM) mass and altered composition of the extracellular matrix (ECM). Studies have indicated that ECM-ASM cell interactions contribute to this remodeling and its limited reversibility with current therapy. Three-dimensional matrices allow the study of complex cellular responses to different stimuli in an almost natural environment. Our goal was to obtain acellular bronchial matrices and then develop a recellularization protocol with ASM cells. We studied equine bronchi as horses spontaneously develop a human asthma-like disease. The bronchi were decellularized using Triton/Sodium Deoxycholate. The obtained scaffolds retained their anatomical and histological properties. Using immunohistochemistry and a semi-quantitative score to compare native bronchi to scaffolds revealed no significant variation for matrixial proteins. DNA quantification and electrophoresis revealed that most DNA was 29.6 ng/mg of tissue ± 5.6, with remaining fragments of less than 100 bp. Primary ASM cells were seeded on the scaffolds. Histological analysis of the recellularizations showed that ASM cells migrated and proliferated primarily in the decellularized smooth muscle matrix, suggesting a chemotactic effect of the scaffolds. This is the first report of primary ASM cells preferentially repopulating the smooth muscle matrix layer in bronchial matrices. This protocol is now being used to study the molecular interactions occurring between the asthmatic ECMs and ASM to identify effectors of asthmatic bronchial remodeling.
JTD Keywords: 2d, airway smooth muscle cells, asthma, decellularization, disease, elastin, extracellular matrix, lung scaffolds, migration, peptide, recellularization, tissues, Airway smooth muscle cells, Animals, Asthma, Bronchi, Culture-systems, Decellularization, Extracellular matrix, Horse diseases, Horses, Muscle, smooth, Myocytes, smooth muscle, Recellularization
Sans, J., Armelin, E., Sanz, V., Puiggalí, J., Turon, P., Alemán, C., (2020). Breaking-down the catalyst used for the electrophotosynthesis of amino acids by nitrogen and carbon fixation Journal of Catalysis 389, 646-656
The electrophotocatalytic synthesis of Glycine and Alanine from a simple gas mixture containing N2, CO2, CH4 and H2O under mild reaction conditions (95 °C and 6 bar) was recently developed using a catalyst formed by permanently polarized hydroxyapatite, which is achieved using a thermally stimulated polarization process, coated with two layers of aminotris(methylenephosphonic acid) (ATMP) separated by an intermediate layer of zirconyl chloride (ZC). This work reports the optimization of the ATMP- and ZC-coating content by examining the influence of their concentration of each component in each layer on the structural and electrochemical properties of the catalyst. After exhaustive analyses, such properties have been related with the efficiency of the catalysts prepared using different ATMP- and ZC-concentrations to yield Gly and Ala amino acids by fixing nitrogen from N2 and carbon from CO2 and CH4. Results show that, although the concentrations of ATMP and ZC in the first and the intermediate layers are important, the third layer plays a predominant role as is responsible of the apparition of supramolecular structures on the surface and the capacitive behavior of the coating
JTD Keywords: Carbon dioxide fixation, Electrocatalyst, Heterogeneous catalysis, Phosphonic acid, Photocatalyst, Polarized hydroxyapatite, Surface chemistry, Zirconyl chloride
Praktiknjo, M., Monteiro, S., Grandt, J., Kimer, N., Madsen, J. L., Werge, M. P., William, P., Brol, M. J., Turco, L., Schierwagen, R., Chang, J., Klein, S., Uschner, F. E., Welsch, C., Moreau, R., Schepis, F., Bendtsen, F., Gluud, L. L., Møller, S., Trebicka, J., (2020). Cardiodynamic state is associated with systemic inflammation and fatal acute-on-chronic liver failure Liver International 40, (6), 1457-1466
Background & Aims: Acute-on-chronic liver failure (ACLF) is characterized by high short-term mortality and systemic inflammation (SI). Recently, different cardiodynamic states were shown to independently predict outcomes in cirrhosis. The relationship between cardiodynamic states, SI, and portal hypertension and their impact on ACLF development remains unclear. The aim of this study was therefore to evaluate the interplay of cardiodynamic state and SI on fatal ACLF development in cirrhosis.
Results: At inclusion, hemodynamic measures including cardiac index (CI) and hepatic venous pressure gradient of 208 patients were measured. Patients were followed prospectively for fatal ACLF development (primary endpoint). SI was assessed by proinflammatory markers such as interleukins (ILs) 6 and 8 and soluble IL-33 receptor (sIL-33R). Patients were divided according to CI (<3.2; 3.2-4.2; >4.2 L/min/m2) in hypo- (n = 84), normo- (n = 69) and hyperdynamic group (n = 55). After a median follow-up of 3 years, the highest risk of fatal ACLF was seen in hyperdynamic (35%) and hypodynamic patients (25%) compared with normodynamic (14%) (P = .011). Hyperdynamic patients showed the highest rate of SI. The detectable level of IL-6 was an independent predictor of fatal ACLF development.
Conclusions: Cirrhotic patients with hyperdynamic and hypodynamic circulation have a higher risk of fatal ACLF. Therefore, the cardiodynamic state is strongly associated with SI, which is an independent predictor of development of fatal ACLF.
JTD Keywords: Acute-on-chronic liver failure, Circulation, Cirrhosis, Hemodynamic, Inflammation
Landa-Castro, Midori, Sebastián, Paula, Giannotti, Marina I., Serrà, Albert, Gómez, Elvira, (2020). Electrodeposition of nanostructured cobalt films from a deep eutectic solvent: Influence of the substrate and deposition potential range Electrochimica Acta 359, 136928
The purpose of this systematic study was to investigate the effects of specific substrates and potential conditions applied while tailoring the morphology and chemical composition of nanostructured Co films. In particular, Co electrodeposition in sustainable choline chloride-urea deep eutectic solvent was assessed, using glassy carbon and two metals widely employed in electrocatalysis and biocompatible purposes, Pt and Au, as substrates for modification with Co. Various in situ electrochemical techniques were combined with a broad range of ex-situ characterization and chemical-composition techniques for a detailed analysis of the prepared Co films. Among the results, nanostructured Co films with high extended active surface areas and variable composition of oxo and hydroxyl species could be tuned by simply modulating the applied potential limits, and without using additives or surfactant agents. The study highlights the effectiveness of using deep eutectic solvent as suitable electrolyte for surface modification by controlled deposition of nanostructured Co films with further application in electrocatalysis.
JTD Keywords: Cobalt electrodeposition, Deep eutectic solvent, First growth stages, Substrate influence
Burgués, Javier, Marco, Santiago, (2020). Environmental chemical sensing using small drones: A review Science of The Total Environment 748, 141172
Recent advances in miniaturization of chemical instrumentation and in low-cost small drones are catalyzing exponential growth in the use of such platforms for environmental chemical sensing applications. The versatility of chemically sensitive drones is reflected by their rapid adoption in scientific, industrial, and regulatory domains, such as in atmospheric research studies, industrial emission monitoring, and in enforcement of environmental regulations. As a result of this interdisciplinarity, progress to date has been reported across a broad spread of scientific and non-scientific databases, including scientific journals, press releases, company websites, and field reports. The aim of this paper is to assemble all of these pieces of information into a comprehensive, structured and updated review of the field of chemical sensing using small drones. We exhaustively review current and emerging applications of this technology, as well as sensing platforms and algorithms developed by research groups and companies for tasks such as gas concentration mapping, source localization, and flux estimation. We conclude with a discussion of the most pressing technological and regulatory limitations in current practice, and how these could be addressed by future research.
JTD Keywords: Unmanned aircraft systems, Remotely piloted aircraft systems, Chemical sensors, Gas sensors, Environmental monitoring, Industrial emission monitoring
Minguela, J., Slawik, S., Mücklich, F., Ginebra, M. P., Llanes, L., Mas-Moruno, C., Roa, J. J., (2020). Evolution of microstructure and residual stresses in gradually ground/polished 3Y-TZP Journal of the European Ceramic Society 40, (4), 1582-1591
A comprehensive study of progressively ground/polished 3Y-TZP was performed with the aim of better understanding the mechanisms driving the microstructural modifications observed after such procedures, and identifying the processing parameters leading to optimal microstructures (i.e. ageing-protective and damage-free). Gradually ground/polished surfaces were produced, yielding four different topographies of increasing roughness (grades 1–4) and two different textures (unidirectionally, U, and multidirectionally, M). Phase transformation, microstructure and residual stresses were investigated by means of advanced characterization techniques. It was found that low-roughness mildly ground/polished specimens (i.e. 2-M/U) presented a nanometric layer with the ageing-related protective features generally associated with coarsely ground specimens. A lower limit for grain refinement in terms of surface abrasion was also found, in which partial recrystallization took place (i.e. 1-M/U). A mathematical relation was established between average surface roughness (Sa), monoclinic volume fraction (Vm) and surface compressive residual stresses, demonstrating that if the processing parameters are controlled, both Vm and residual stresses can be predicted by the measurement of Sa.
JTD Keywords: Grinding, Microstructure, Phase transformation, Residual stresses, Zirconia
Minguela, J., Ginebra, M. P., Llanes, L., Mas-Moruno, C., Roa, J. J., (2020). Influence of grinding/polishing on the mechanical, phase stability and cell adhesion properties of yttria-stabilized zirconia Journal of the European Ceramic Society 40, (12), 4304-4314
The changes in mechanical properties, hydrothermal degradation and cell adhesion were studied in 3Y-TZP under two different superficial modification patterns (uni- and multidirectional) with a surface roughness ranging from 16 to 603 nm. In this sense, mechanical properties (i.e. hardness, indentation fracture toughness and scratch) and accelerated tests in water steam were measured to evaluate the influence of the surface treatments on the superficially modified layer. Moreover, a detailed characterization through micro-Raman spectroscopy and X-Ray diffraction was performed. Finally, SaOS-2 osteoblasts were used for the evaluation of the cell adhesion behaviour on the surfaces. Overall, ground/polished specimens increased the mechanical properties and ageing resistance of mirror-like polished specimens, although resistance to degradation was maximum at intermediate conditions (Sa ≈ 40−180 nm). The studied surfaces allowed cell attachment, but promoted contact guidance (i.e. cell alignment) only on unidirectionally ground surfaces above Sa = 150 nm.
JTD Keywords: Cell adhesion, Grinding, Hydrothermal degradation, Mechanical properties, Zirconia
Monteil, Vanessa, Kwon, Hyesoo, Prado, Patricia, Hagelkrüys, Astrid, Wimmer, Reiner A., Stahl, Martin, Leopoldi, Alexandra, Garreta, Elena, Hurtado Del Pozo, Carmen, Prosper, Felipe, Romero, Juan Pablo, Wirnsberger, Gerald, Zhang, Haibo, Slutsky, Arthur S., Conder, Ryan, Montserrat, Nuria, Mirazimi, Ali, Penninger, Josef M., (2020). Inhibition of SARS-CoV-2 infections in engineered human tissues using clinical-grade soluble human ACE2 Cell 181, (4), 905-913.e7
We have previously provided the first genetic evidence that angiotensin converting enzyme 2 (ACE2) is the critical receptor for severe acute respiratory syndrome coronavirus (SARS-CoV), and ACE2 protects the lung from injury, providing a molecular explanation for the severe lung failure and death due to SARS-CoV infections. ACE2 has now also been identified as a key receptor for SARS-CoV-2 infections, and it has been proposed that inhibiting this interaction might be used in treating patients with COVID-19. However, it is not known whether human recombinant soluble ACE2 (hrsACE2) blocks growth of SARS-CoV-2. Here, we show that clinical grade hrsACE2 reduced SARS-CoV-2 recovery from Vero cells by a factor of 1,000-5,000. An equivalent mouse rsACE2 had no effect. We also show that SARS-CoV-2 can directly infect engineered human blood vessel organoids and human kidney organoids, which can be inhibited by hrsACE2. These data demonstrate that hrsACE2 can significantly block early stages of SARS-CoV-2 infections.
JTD Keywords: COVID-19, Angiotensin converting enzyme 2, Blood vessels, Human organoids, Kidney, Severe acute respiratory syndrome coronavirus, Spike glycoproteins, Treatment
Gabasa, M., Arshakyan, M., Llorente, A., Chuliá-Peris, L., Pavelescu, I., Xaubet, A., Pereda, J., Alcaraz, J., (2020). Interleukin-1β modulation of the mechanobiology of primary human pulmonary fibroblasts: Potential implications in lung repair International Journal of Molecular Sciences 21, (22), 8417
Pro-inflammatory cytokines like interleukin-1β (IL-1β) are upregulated during early responses to tissue damage and are expected to transiently compromise the mechanical microenvironment. Fibroblasts are key regulators of tissue mechanics in the lungs and other organs. However, the effects of IL-1β on fibroblast mechanics and functions remain unclear. Here we treated human pulmonary fibroblasts from control donors with IL-1β and used Atomic Force Microscopy to unveil that IL-1β significantly reduces the stiffness of fibroblasts concomitantly with a downregulation of filamentous actin (F-actin) and alpha-smooth muscle (α-SMA). Likewise, COL1A1 mRNA was reduced, whereas that of collagenases MMP1 and MMP2 were upregulated, favoring a reduction of type-I collagen. These mechanobiology changes were functionally associated with reduced proliferation and enhanced migration upon IL-1β stimulation, which could facilitate lung repair by drawing fibroblasts to sites of tissue damage. Our observations reveal that IL-1β may reduce local tissue rigidity by acting both intracellularly and extracellularly through the downregulation of fibroblast contractility and type I collagen deposition, respectively. These IL-1β-dependent mechanical effects may enhance lung repair further by locally increasing pulmonary tissue compliance to preserve normal lung distension and function. Moreover, our results support that IL-1β provides innate anti-fibrotic protection that may be relevant during the early stages of lung repair.
JTD Keywords: Cell mechanics, Collagen, IL-1β, MMPs, Pulmonary fibroblasts, Repair
De Matteis, Valeria, Rizzello, Loris, (2020). Noble metals and soft bio-inspired nanoparticles in retinal diseases treatment: A perspective Cells 9, (3), 679
We are witnessing an exponential increase in the use of different nanomaterials in a plethora of biomedical fields. We are all aware of how nanoparticles (NPs) have influenced and revolutionized the way we supply drugs or how to use them as therapeutic agents thanks to their tunable physico-chemical properties. However, there is still a niche of applications where NP have not yet been widely explored. This is the field of ocular delivery and NP-based therapy, which characterizes the topic of the current review. In particular, many efforts are being made to develop nanosystems capable of reaching deeper sections of the eye such as the retina. Particular attention will be given here to noble metal (gold and silver), and to polymeric nanoparticles, systems consisting of lipid bilayers such as liposomes or vesicles based on nonionic surfactant. We will report here the most relevant literature on the use of different types of NPs for an efficient delivery of drugs and bio-macromolecules to the eyes or as active therapeutic tools.
JTD Keywords: Bio-inspired NPs, Drug delivery, Noble metals NPs, Retinal diseases
Brugada-Vilà , P., Cascante, A., Lázaro, M. Á., Castells-Sala, C., Fornaguera, C., Rovira-Rigau, M., Albertazzi, L., Borros, S., Fillat, C., (2020). Oligopeptide-modified poly(beta-amino ester)s-coated AdNuPARmE1A: Boosting the efficacy of intravenously administered therapeutic adenoviruses Theranostics 10, (6), 2744-2758
Oncolytic adenoviruses are used as agents for the treatment of cancer. However, their potential is limited due to the high seroprevalence of anti-adenovirus neutralizing antibodies (nAbs) within the population and the rapid liver sequestration when systemically administered. To overcome these challenges, we explored using nanoparticle formulation to boost the efficacy of systemic oncolytic adenovirus administration. Methods: Adenovirus were conjugated with PEGylated oligopeptide-modified poly(β-amino ester)s (OM-pBAEs). The resulting coated viral formulation was characterized in terms of surface charge, size, aggregation state and morphology and tested for anti-adenovirus nAbs evasion and activity in cancer cells. In vivo pharmacokinetics, biodistribution, tumor targeting, and immunogenicity studies were performed. The antitumor efficacy of the oncolytic adenovirus AdNuPARmE1A coated with OM-pBAEs (SAG101) in the presence of nAbs was evaluated in pancreatic ductal adenocarcinoma (PDAC) mouse models. Toxicity of the coated formulation was analyzed in vivo in immunocompetent mice. Results: OM-pBAEs conjugated to adenovirus and generated discrete nanoparticles with a neutral charge and an optimal size. The polymeric coating with the reporter AdGFPLuc (CPEG) showed enhanced transduction and evasion of antibody neutralization in vitro. Moreover, systemic intravenous administration of the formulation showed improved blood circulation and reduced liver sequestration, substantially avoiding activation of nAb production. OM-pBAEs coating of the oncolytic adenovirus AdNuPARmE1A (SAG101) improved its oncolytic activity in vitro and enhanced antitumor efficacy in PDAC mouse models. The coated formulation protected virions from neutralization by nAbs, as antitumor efficacy was preserved in their presence but was completely lost in mice that received the non-formulated AdNuPARmE1A. Finally, coated-AdNuPARmE1A showed reduced toxicity when high doses of the formulation were administered. Conclusions: The developed technology represents a promising improvement for future clinical cancer therapy using oncolytic adenoviruses.
JTD Keywords: Oncolytic adenovirus, Pancreatic cancer, Poly(β-amino ester)s, Polymer-coated viral vectors, Systemic delivery
Madsen, B. S., Thiele, M., Detlefsen, S., Sørensen, M. D., Kjærgaard, M., Møller, L. S., Rasmussen, D. N., Schlosser, A., Holmskov, U., Trebicka, J., Sorensen, G. L., Krag, A., (2020). Prediction of liver fibrosis severity in alcoholic liver disease by human microfibrillar-associated protein 4 Liver International 40, (7), 1701-1712
Background: Alcoholic liver disease (ALD) is a public health concern that is the cause of half of all cirrhosis-related deaths. Early detection of fibrosis, ideally in the precirrhotic stage, is a key strategy for improving ALD outcomes and for preventing progression to cirrhosis. Previous studies identified the blood-borne marker human microfibrillar-associated protein 4 (MFAP4) as a biomarker for detection of hepatitis C virus (HCV)-related fibrosis. Aim: To evaluate the diagnostic accuracy of MFAP4 to detect ALD-induced fibrosis. Method: We performed a prospective, liver biopsy-controlled study involving 266 patients with prior or current alcohol overuse. Patients were split into a training and a validation cohort. Results: MFAP4 was present in fibrotic hepatic tissue and serum MFAP4 levels increased with fibrosis grade. The area under the receiver operating characteristic curve (AUROC) for detection of cirrhosis was 0.91 (95% CI 0.85-0.96) in the training cohort and 0.91 (95% CI 0.79-1.00) in the validation cohort. For detection of advanced fibrosis, the AUROC was 0.88 (95% CI 0.81-0.94) in the training cohort and 0.92 (95% CI 0.83-1.00) in the validation cohort. The diagnostic accuracy did not differ between MFAP4 and the enhanced liver fibrosis (ELF) test or transient elastography (TE) in an intention-to-diagnose analysis. MFAP4 did not predict hepatic decompensation in a time-to-decompensation analysis in a subgroup of patients with cirrhosis. Conclusion: MFAP4 is a novel biomarker that can detect ALD-related fibrosis with high accuracy.
JTD Keywords: Biomarker, Cirrhosis, Extracellular matrix protein, Liver biopsy, Non-invasive testing
Trebicka, J., Gu, W., Ibañez-Samaniego, L., Hernández-Gea, V., Pitarch, C., Garcia, E., Procopet, B., Giráldez, Ã, Amitrano, L., Villanueva, C., Thabut, D., Silva-Junior, G., Martinez, J., Genescà , J., Bureau, C., Llop, E., Laleman, W., Palazon, J. M., Castellote, J., Rodrigues, S., Gluud, L., Ferreira, C. N., Barcelo, R., Cañete, N., Rodríguez, M., Ferlitsch, A., Mundi, J. L., Gronbaek, H., Hernández-Guerra, M., Sassatelli, R., Dell'Era, A., Senzolo, M., Abraldes, J. G., Romero-Gómez, M., Zipprich, A., Casas, M., Masnou, H., Primignani, M., Weiss, E., Catalina, M. V., Erasmus, H. P., Uschner, F. E., Schulz, M., Brol, M. J., Praktiknjo, M., Chang, J., Krag, A., Nevens, F., Calleja, J. L., Robic, M. A., Conejo, I., Albillos, A., Rudler, M., Alvarado, E., Guardascione, M. A., Tantau, M., Bosch, J., Torres, F., Pavesi, M., Garcia-Pagán, J. C., Jansen, C., Bañares, R., (2020). Rebleeding and mortality risk are increased by ACLF but reduced by pre-emptive TIPS Journal of Hepatology 73, (5), 1082-1091
Background & Aims: The relationship between acute-on-chronic liver failure (ACLF) and acute variceal bleeding (AVB) is poorly understood. Specifically, the prevalence and prognosis of ACLF in the context of AVB is unclear, while the role of transjugular intrahepatic portosystemic shunt (TIPS) in the management in patients with ACLF has not been described to date.
Methods: A multicenter, international, observational study was conducted in 2,138 patients from 34 centers between 2011 and 2015. ACLF was defined and graded according to the EASL-CLIF consortium definition. Placement of pre-emptive TIPS (pTIPS) was based on individual center policy. Patients were followed-up for 1 year, until death or liver transplantation. Cox regression and competing risk models (Gray's test) were used to identify independent predictors of rebleeding or mortality.
Results: At admission, 380/2,138 (17.8%) patients had ACLF according to EASL-CLIF criteria (grade 1: 38.7%; grade 2: 39.2%; grade 3: 22.1%). The 42-day rebleeding (19% vs. 10%; p <0.001) and mortality (47% vs. 10%; p <0.001) rates were higher in patients with ACLF and increased with ACLF grades. Of note, the presence of ACLF was independently associated with rebleeding and mortality. pTIPS placement improved survival in patients with ACLF at 42 days and 1 year. This effect was also observed in propensity score matching analysis of 66 patients with ACLF, of whom 44 received pTIPs and 22 did not.
Conclusions: This large multicenter international real-life study identified ACLF at admission as an independent predictor of rebleeding and mortality in patients with AVB. Moreover, pTIPS was associated with improved survival in patients with ACLF and AVB.
Lay summary: Acute variceal bleeding is a deadly complication of liver cirrhosis that results from severe portal hypertension. This study demonstrates that the presence of acute-on-chronic liver failure (ACLF) is the strongest predictor of mortality in patients with acute variceal bleeding. Importantly, patients with ACLF and acute variceal (re)bleeding benefit from pre-emptive (early) placement of a transjugular intrahepatic portosystemic shunt.
JTD Keywords: Acute variceal bleeding, Acute-on-chronic liver failure, Cirrhosis, Rebleeding
Sierra, J., Marrugo-Ramírez, J., Rodriguez-Trujillo, R., Mir, M., Samitier, J., (2020). Sensor-integrated microfluidic approaches for liquid biopsies applications in early detection of cancer Sensors 20, (5), 1317
Cancer represents one of the conditions with the most causes of death worldwide. Common methods for its diagnosis are based on tissue biopsies—the extraction of tissue from the primary tumor, which is used for its histological analysis. However, this technique represents a risk for the patient, along with being expensive and time-consuming and so it cannot be frequently used to follow the progress of the disease. Liquid biopsy is a new cancer diagnostic alternative, which allows the analysis of the molecular information of the solid tumors via a body fluid draw. This fluid-based diagnostic method displays relevant advantages, including its minimal invasiveness, lower risk, use as often as required, it can be analyzed with the use of microfluidic-based platforms with low consumption of reagent, and it does not require specialized personnel and expensive equipment for the diagnosis. In recent years, the integration of sensors in microfluidics lab-on-a-chip devices was performed for liquid biopsies applications, granting significant advantages in the separation and detection of circulating tumor nucleic acids (ctNAs), circulating tumor cells (CTCs) and exosomes. The improvements in isolation and detection technologies offer increasingly sensitive and selective equipment’s, and the integration in microfluidic devices provides a better characterization and analysis of these biomarkers. These fully integrated systems will facilitate the generation of fully automatized platforms at low-cost for compact cancer diagnosis systems at an early stage and for the prediction and prognosis of cancer treatment through the biomarkers for personalized tumor analysis.
JTD Keywords: Cancer, Circulant tumor cells (CTC), Circulant tumor DNA (ctDNA), Exosomes, Liquid biopsy, Microfluidic, Sensors
Torner, M., Mangal, A., Scharnagl, H., Jansen, C., Praktiknjo, M., Queck, A., Gu, W., Schierwagen, R., Lehmann, J., Uschner, F. E., Graf, C., Strassburg, C. P., Fernandez, J., Stojakovic, T., Woitas, R., Trebicka, J., (2020). Sex specificity of kidney markers to assess prognosis in cirrhotic patients with TIPS Liver International 40, (1), 186-193
Background & Aims: Renal function assessed by creatinine is a key prognostic factor in cirrhotic patients. However, creatinine is influenced by several factors, rendering interpretation difficult in some situations. This is especially important in early stages of renal dysfunction where renal impairment might not be accompanied by an increase in creatinine. Other parameters, such as cystatin C (CysC) and beta‐trace protein (BTP), have been evaluated to fill this gap. However, none of these studies have considered the role of the patient's sex. The present study analysed CysC and BTP to evaluate their prognostic value and differentiate them according to sex.
Patients and methods: CysC and BTP were measured in 173 transjugular intrahepatic portosystemic shunt (TIPS)-patients from the NEPTUN-STUDY(NCT03628807) and analysed their relationship with mortality and sex. Propensity score for age, MELD, etiology and TIPS indication was used.
Results: Cystatin C and BTP showed excellent correlations with creatinine values at baseline and follow-up. CysC was an independent predictor of overall mortality (HR = 1.66(1.33-2.06)) with an AUC of 0.75 and identified a cut-off of 1.55 mg/L in the whole cohort. Interestingly, CysC was significantly lower in females, also after propensity score matching. In males, the only independent predictor was the creatinine level (HR = 1.54(1.25-1.58)), while in females CysC levels independently predicted mortality (HR = 3.17(1.34-7.52)).
Conclusion: This study demonstrates for the first time that in TIPS-patients creatinine predicts mortality in males better than in females, whereas CysC is a better predictor of mortality in females. These results may influence future clinical decisions on therapeutic options for example, allocation for liver transplantation in TIPS-patients.
JTD Keywords: Beta-trace protein, Cirrhosis, Cystatin C, Portal hypertension, Renal function
De Corato, M., Pagonabarraga, I., Abdelmohsen, L. K. E. A., Sánchez, S., Arroyo, M., (2020). Spontaneous polarization and locomotion of an active particle with surface-mobile enzymes Physical Review Fluids 5, (12), 122001
We examine a mechanism of locomotion of active particles whose surface is uniformly coated with mobile enzymes. The enzymes catalyze a reaction that drives phoretic flows but their homogeneous distribution forbids locomotion by symmetry. We find that the ability of the enzymes to migrate over the surface combined with self-phoresis can lead to a spontaneous symmetry-breaking instability whereby the homogeneous distribution of enzymes polarizes and the particle propels. The instability is driven by the advection of enzymes by the phoretic flows and occurs above a critical Péclet number. The transition to polarized motile states occurs via a supercritical or subcritical pitchfork bifurcations, the latter of which enables hysteresis and coexistence of uniform and polarized states.
JTD Keywords: Biomimetic & bio-inspired materials, Locomotion, Surface-driven phase separation
Vidal, E., Torres, D., Guillem-Marti, J., Scionti, G., Manero, J. M., Ginebra, M. P., Rodríguez, D., Rupérez, E., (2020). Titanium scaffolds by direct ink writing: Fabrication and functionalization to guide osteoblast behavior Metals 10, (9), 1156
Titanium (Ti) and Ti alloys have been used for decades for bone prostheses due to its mechanical reliability and good biocompatibility. However, the high stiffness of Ti implants and the lack of bioactivity are pending issues that should be improved to minimize implant failure. The stress shielding effect, a result of the stiffness mismatch between titanium and bone, can be reduced by introducing a tailored structural porosity in the implant. In this work, porous titanium structures were produced by direct ink writing (DIW), using a new Ti ink formulation containing a thermosensitive hydrogel. A thermal treatment was optimized to ensure the complete elimination of the binder before the sintering process, in order to avoid contamination of the titanium structures. The samples were sintered in argon atmosphere at 1200 °C, 1300 °C or 1400 °C, resulting in total porosities ranging between 72.3% and 77.7%. A correlation was found between the total porosity and the elastic modulus of the scaffolds. The stiffness and yield strength were similar to those of cancellous bone. The functionalization of the scaffold surface with a cell adhesion fibronectin recombinant fragment resulted in enhanced adhesion and spreading of osteoblastic-like cells, together with increased alkaline phosphatase expression and mineralization.
JTD Keywords: Direct ink writing, Osseointegration, Recombinant protein, Thermoresponsive binder, Titanium, Titanium scaffold
Praktiknjo, M., Simón-Talero, M., Römer, J., Roccarina, D., Martínez, J., Lampichler, K., Baiges, A., Low, G., Llop, E., Maurer, M. H., Zipprich, A., Triolo, M., Maleux, G., Fialla, A. D., Dam, C., Vidal-González, J., Majumdar, A., Picón, C., Toth, D., Darnell, A., Abraldes, J. G., López, M., Jansen, C., Chang, J., Schierwagen, R., Uschner, F., Kukuk, G., Meyer, C., Thomas, D., Wolter, K., Strassburg, C. P., Laleman, W., La Mura, V., Ripoll, C., Berzigotti, A., Calleja, J. L., Tandon, P., Hernandez-Gea, V., Reiberger, T., Albillos, A., Tsochatzis, E. A., Krag, A., Genescà , J., Trebicka, J., (2020). Total area of spontaneous portosystemic shunts independently predicts hepatic encephalopathy and mortality in liver cirrhosis Journal of Hepatology 72, (6), 1140-1150
Background & Aims: Spontaneous portosystemic shunts (SPSS) frequently develop in liver cirrhosis. Recent data suggested that the presence of a single large SPSS is associated with complications, especially overt hepatic encephalopathy (oHE). However, the presence of >1 SPSS is common. This study evaluates the impact of total cross-sectional SPSS area (TSA) on outcomes in patients with liver cirrhosis.
Methods: In this retrospective international multicentric study, CT scans of 908 cirrhotic patients with SPSS were evaluated for TSA. Clinical and laboratory data were recorded. Each detected SPSS radius was measured and TSA calculated. One-year survival was the primary endpoint and acute decompensation (oHE, variceal bleeding, ascites) was the secondary endpoint.
Results: A total of 301 patients (169 male) were included in the training cohort. Thirty percent of all patients presented with >1 SPSS. A TSA cut-off of 83 mm2 was used to classify patients with small or large TSA (S-/L-TSA). Patients with L-TSA presented with higher model for end-stage liver disease score (11 vs. 14) and more commonly had a history of oHE (12% vs. 21%, p <0.05). During follow-up, patients with L-TSA experienced more oHE episodes (33% vs. 47%, p <0.05) and had lower 1-year survival than those with S-TSA (84% vs. 69%, p <0.001). Multivariate analysis identified L-TSA (hazard ratio 1.66; 95% CI 1.02–2.70, p <0.05) as an independent predictor of mortality. An independent multicentric validation cohort of 607 patients confirmed that patients with L-TSA had lower 1-year survival (77% vs. 64%, p <0.001) and more oHE development (35% vs. 49%, p <0.001) than those with S-TSA.
Conclusion: This study suggests that TSA >83 mm2 increases the risk for oHE and mortality in patients with cirrhosis. Our results support the clinical use of TSA/SPSS for risk stratification and decision-making in the management of patients with cirrhosis.
Lay summary: The prevalence of spontaneous portosystemic shunts (SPSS) is higher in patients with more advanced chronic liver disease. The presence of more than 1 SPSS is common in advanced chronic liver disease and is associated with the development of hepatic encephalopathy. This study shows that total cross-sectional SPSS area (rather than diameter of the single largest SPSS) predicts survival in patients with advanced chronic liver disease. Our results support the clinical use of total cross-sectional SPSS area for risk stratification and decision-making in the management of SPSS.
JTD Keywords: ACLF, Acute decompensation, Acute-on-chronic liver failure, Ascites, Cirrhosis, Computed tomography, Hepatic encephalopathy, Liver, Portal hypertension, Spontaneous portosystemic shunt, SPSS, TIPS
Almici, Enrico, Caballero, David, Montero, Joan, Samitier, Josep, (2020). 3D neuroblastoma in vitro models using engineered cell-derived matrices
Biomaterials for 3D Tumor Modeling (ed. Kundu, Subhas C., Reis, Rui L.), Elsevier (Amsterdam, Netherlands) , 107-130
Neuroblastoma (NB) is a malignant tumor that affects the peripheral nervous system and represents one of the most frequent cancers in infants. Its prognosis is poor in older patients and the presence of genetic abnormalities. Metastasis is often present at the time of diagnosis, making treatment more intensive and unsuccessful. Poor prognosis and variable treatment efficacy require a better understanding of the underlying biology. Evidence has shown that the tumor microenvironment is the characteristic of tumor malignancy and progression. A more highly differentiated tissue phenotype represents a positive prognostic marker, while the tumoral tissue is characterized by a distinct composition and morphology of the extracellular matrix (ECM). In this chapter, we discuss the application of decellularized cell-derived matrices (CDMs) to model in vitro the morphology of the ECM encountered in histological hallmarks of NB patients. This technique allows for the in vitro reproduction of the fine structure and composition of native microenvironments. Because of recent advances in culture systems and decellularization techniques, it is possible to engineer CDM composition and microarchitecture to produce differentiated models of tissue niches. The final goal is to repopulate the “scaffold” with malignant NB cells for drug screening and target discovery applications, studying the impact of patient-inspired tissues on signaling, migration, and tissue remodeling.
JTD Keywords: Neuroblastoma, Cancer, Bioengineering, Tumor microenvironment, Cell-derived matrices, Decellularization
Rahman, Abdel, Ganesh, Swapnil, Torrents, Eduard, Jahan, Nusrat, Wedyan, Moh'd Ali, Qaisi, Ali M., Al-Tawaha, Abdelrazzaq, (2020). Algal viruses
Applied Plant Virology (ed. Awasthi, L. P.), Academic Press (London, UK) Advances, Detection, and Antiviral Strategies, 237-246
In marine ecosystems, the algae community is abundant and plays an important role in the food web. On the other hand, algal viruses have different advantages and disadvantages depending on the properties, such as applications of algal viruses in the advancement of molecular biology and for enhancement of biofuel production. Many environmental factors affecting growth and development of algae and virus such as temperature, salinity, ultraviolet radiation, photosynthetic active radiation, nutrients, inorganic particles, organic particles, CO2 concentration, and pH.
JTD Keywords: Algal viruses, Biofuel production, Nutrients
Vouloutsi, Vasiliki, Mura, Anna, Tauber, F., Speck, T., Prescott, T. J., Verschure, P., (2020). Biomimetic and Biohybrid Systems
9th International Conference, Living Machines 2020, Freiburg, Germany, July 28–30, 2020, Proceedings , Springer, Cham (Lausanne, Switzerland) 12413, 1-428
This book constitutes the proceedings of the )th International Conference on Biomimetic and Biohybrid Systems, Living Machines 2020, held in Freiburg, Germany, in July 2020. Due to COVID-19 pandemic the conference was held virtually. The 32 full and 7 short papers presented in this volume were carefully reviewed and selected from 45 submissions. They deal with research on novel life-like technologies inspired by the scientific investigation of biological systems, biomimetics, and research that seeks to interface biological and artificial systems to create biohybrid systems.
JTD Keywords: Artificial intelligence, Soft robotics, Biomimetics, Insect navigation, Synthetic nervous system, Computer vision, Bio-inspired materials, Visual homing, Locomotion+, Image processing, Intelligent robots, Human-robot interaction, Machine learning, Snake robot, Mobile robots, Robotic systems, Drosophila, Robots, Sensors, Signal processing
Pujals, S., Feiner-Gracia, N., Delcanale, P., Voets, I., Albertazzi, L., (2019). Super-resolution microscopy as a powerful tool to study complex synthetic materials Nature Reviews Chemistry 3, (2), 68-84
Understanding the relations between the formation, structure, dynamics and functionality of complex synthetic materials is one of the great challenges in chemistry and nanotechnology and represents the foundation for the rational design of novel materials for a variety of applications. Initially conceived to study biology below the diffraction limit, super-resolution microscopy (SRM) is emerging as a powerful tool for studying synthetic materials owing to its nanometric resolution, multicolour ability and minimal invasiveness. In this Review, we provide an overview of the pioneering studies that use SRM to visualize materials, highlighting exciting recent developments such as experiments in operando, wherein materials, such as biomaterials in a biological environment, are imaged in action. Moreover, the potential and the challenges of the different SRM methods for application in nanotechnology and (bio)materials science are discussed, aiming to guide researchers to select the best SRM approach for their specific purpose.
JTD Keywords: Bioinspired materials, Imaging techniques
Trebicka, J., Bastgen, D., Byrtus, J., Praktiknjo, M., Terstiegen, S., Meyer, C., Thomas, D., Fimmers, R., Treitl, M., Euringer, W., Sauerbruch, T., Rössle, M., (2019). Smaller-diameter covered transjugular intrahepatic portosystemic shunt stents are associated with increased survival Clinical Gastroenterology and Hepatology 17, (13), 2793-2799.e1
Background & Aims: We studied the effects of diameter of covered, self-expandable, nitinol stents on survival times of patients with a transjugular intrahepatic portosystemic shunt (TIPS).
Methods: We collected data from 185 patients (median age, 55 y; 30% female) who received a covered nitinol stent, from February 2006 through September 2010, using the online multicenter German TIPS registry. TIPS were given to 107 patients for refractory ascites and to 78 patients for variceal bleeding. Patients at risk of hepatic encephalopathy (owing to advanced age, prior episodes) or liver failure (bilirubin level, >3 mg/dL), and bleeding patients receiving variceal embolization at TIPS, received 8-mm stents (n = 53). The remaining patients received 10-mm stents (n = 132). Eighty-one of the 10-mm stents were underdilated using 8-mm dilation balloons. Clinical and biochemical data were collected after TIPS placement at 1 month, 3 months, 6 months, 9 months, 1 year, and thereafter every 3 to 6 months. Groups were compared using propensity score analysis.
Results: Patients who received 8-mm stents survived significantly longer (34 ± 26 mo) than patients who received 10-mm stents (18 ± 19 mo), regardless of whether they were fully dilated or underdilated. When we compared 10-mm stents with or without underdilation, we found that a significantly higher proportion of patients who received underdilated stents survived for 1 month after TIPS placement (95% vs 84%; P = .03), but not for 3 months (P = .10). In multivariate analysis, 1-year mortality correlated with full dilation of the stent to 10 mm (hazard ratio [HR], 2.0; 95% CI, 1.1–3.5) and with serum creatinine concentration at baseline (HR, 1.5; 95% CI, 1.0–1.7). Five-year mortality was associated with use of the 10-mm stents (HR, 1.8; 95% CI, 1.4–2.7) and baseline concentration of creatinine (HR, 1.3; 95% CI, 1.1–1.6).
Conclusions: A smaller stent (nominal diameter of 8 mm, but not underdilation of a 10-mm stent) is associated with a prolonged survival compared with 10-mm stents, independent of liver-specific prognostic criteria.
JTD Keywords: Cirrhosis, Comparison, Covered, Portal Hypertension
Kaurin, D., Arroyo, M., (2019). Surface tension controls the hydraulic fracture of adhesive interfaces bridged by molecular bonds Physical Review Letters 123, (22), 228102
Biological function requires cell-cell adhesions to tune their cohesiveness; for instance, during the opening of new fluid-filled cavities under hydraulic pressure. To understand the physical mechanisms supporting this adaptability, we develop a stochastic model for the hydraulic fracture of adhesive interfaces bridged by molecular bonds. We find that surface tension strongly enhances the stability of these interfaces by controlling flaw sensitivity, lifetime, and optimal architecture in terms of bond clustering. We also show that bond mobility embrittles adhesions and changes the mechanism of decohesion. Our study provides a mechanistic background to understand the biological regulation of cell-cell cohesion and fracture.
JTD Keywords: Biomimetic & bio-inspired materials, Cell adhesion, Fracture, Self-healing
Grechuta, K., Rubio Ballester, B., Espín Munne, R., Usabiaga Bernal, T., Molina Hervás, B., Mohr, B., Pulvermüller, F., San Segundo, R., Verschure, P., (2019). Augmented dyadic therapy boosts recovery of language function in patients with nonfluent aphasia Stroke 50, (5), 1270-1274
Background and Purpose- Evidence suggests that therapy can be effective in recovering from aphasia, provided that it consists of socially embedded, intensive training of behaviorally relevant tasks. However, the resources of healthcare systems are often too limited to provide such treatment at sufficient dosage. Hence, there is a need for evidence-based, cost-effective rehabilitation methods. Here, we asked whether virtual reality-based treatment grounded in the principles of use-dependent learning, behavioral relevance, and intensity positively impacts recovery from nonfluent aphasia. Methods- Seventeen patients with chronic nonfluent aphasia underwent intensive therapy in a randomized, controlled, parallel-group trial. Participants were assigned to the control group (N=8) receiving standard treatment or to the experimental group (N=9) receiving augmented embodied therapy with the Rehabilitation Gaming System for aphasia. All Rehabilitation Gaming System for aphasia sessions were supervised by an assistant who monitored the patients but did not offer any elements of standard therapy. Both interventions were matched for intensity and materials. Results- Our results revealed that at the end of the treatment both groups significantly improved on the primary outcome measure (Boston Diagnostic Aphasia Examination: control group, P=0.04; experimental group, P=0.01), and the secondary outcome measure (lexical access-vocabulary test: control group, P=0.01; experimental group, P=0.007). However, only the Rehabilitation Gaming System for aphasia group improved on the Communicative Aphasia Log ( P=0.01). The follow-up assessment (week 16) demonstrated that while both groups retained vocabulary-related changes (control group, P=0.01; experimental group, P=0.007), only the Rehabilitation Gaming System for aphasia group showed therapy-induced improvements in language ( P=0.01) and communication ( P=0.05). Conclusions- Our results demonstrate the effectiveness of Rehabilitation Gaming System for aphasia for improving language and communication in patients with chronic aphasia suggesting that current challenges faced by the healthcare system in the treatment of stroke might be effectively addressed by augmenting traditional therapy with computer-based methods. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02928822.
JTD Keywords: Aphasia, Embodied training, Neurological rehabilitation, Virtual reality
Rafols-de-Urquia, M., Estrada, L., Estevez-Piorno, J., Sarlabous, L., Jane, R., Torres, A., (2019). Evaluation of a wearable device to determine cardiorespiratory parameters from surface diaphragm electromyography IEEE Journal of Biomedical and Health Informatics 23, (5), 1964-1971
The use of wearable devices in clinical routines could reduce healthcare costs and improve the quality of assessment in patients with chronic respiratory diseases. The purpose of this study is to evaluate the capacity of a Shimmer3 wearable device to extract reliable cardiorespiratory parameters from surface diaphragm electromyography (EMGdi). Twenty healthy volunteers underwent an incremental load respiratory test whilst EMGdi was recorded with a Shimmer3 wearable device (EMGdiW). Simultaneously, a second EMGdi (EMGdiL), inspiratory mouth pressure (Pmouth) and lead-I electrocardiogram (ECG) were recorded via a standard wired laboratory acquisition system. Different cardiorespiratory parameters were extracted from both EMGdiW and EMGdiL signals: heart rate, respiratory rate, respiratory muscle activity and mean frequency of EMGdi signals. Alongside these, similar parameters were also extracted from reference signals (Pmouth and ECG). High correlations were found between the data extracted from the EMGdiW and the reference signal data: heart rate (R = 0.947), respiratory rate (R = 0.940), respiratory muscle activity (R = 0.877), and mean frequency (R = 0.895). Moreover, similar increments in EMGdiW and EMGdiL activity were observed when Pmouth was raised, enabling the study of respiratory muscle activation. In summary, the Shimmer3 device is a promising and cost-effective solution for the ambulatory monitoring of respiratory muscle function in chronic respiratory diseases.
JTD Keywords: Cardiorespiratory monitoring, Chronic respiratory diseases, Fixed sample entropy, Non-invasive respiratory monitoring, Surface diaphragm electromyography, Wearable wireless device
Lehmann, J., Praktiknjo, M., Nielsen, M. J., Schierwagen, R., Meyer, C., Thomas, D., Violi, F., Strassburg, C. P., Bendtsen, F., Moller, S., Krag, A., Karsdal, M. A., Leeming, D. J., Trebicka, J., (2019). Collagen type IV remodelling gender-specifically predicts mortality in decompensated cirrhosis Liver International 39, (5), 885-893
Background & Aims: Remodelling of extracellular matrix is crucial in progressive liver fibrosis. Collagen type III desposition has been shown in acute decompensation. Extratracellular matrix is compiled of deposition of various components. The role of basement membrane collagen type IV in advanced cirrhosis and acute decompensation is unclear and investigated in this study. Methods: Patients with decompensated cirrhosis from the prospective NEPTUN cohort (ClinicalTrials.gov Identifier: NCT03628807), who underwent transjugular intrahepatic portosystemic shunt procedure were included. Clinical and laboratory parameters, PRO-C4 and C4M levels were measured in blood samples from portal and hepatic veins just before transjugular intrahepatic portosystemic shunt placement. Results: Levels of C4M and PRO-C4 are significantly lower in patients with massive ascites and impaired renal sodium excretion. C4M and PRO-C4 show gender-specific profiles with significantly lower levels in females compared to males. Females with higher C4M levels show higher mortality. By contrast, males with higher C4M levels show lower mortality. In multivariate Cox regression analysis, C4M is an independent predictor of survival in female patients. Conclusion: This study shows that markers of collagen type IV remodelling do not accumulate in severe renal dysfunction. Although collagen type IV degradation markers derive from the liver, portal venous C4M levels are relevant for survival. Moreover, it demonstrates that circulating C4M shows gender-specific profiles, which can independently predict survival in female patients with decompensated cirrhosis.
JTD Keywords: ACLF, Acute decompensation, Acute-on-chronic liver failure, Cirrhosis, Collagen type IV, Extracellular matrix remodelling, Gender, Liver, Portal hypertension, Transjugular intrahepatic portosystemic shunt
Trebicka, J., Amoros, A., Pitarch, C., Titos, E., Alcaraz-Quiles, J., Schierwagen, R., Deulofeu, C., Fernandez-Gomez, J., Piano, S., Caraceni, P., Oettl, K., Sola, E., Laleman, W., McNaughtan, J., Mookerjee, R. P., Coenraad, M. J., Welzel, T., Steib, C., Garcia, R., Gustot, T., Rodriguez Gandia, M. A., Bañares, R., Albillos, A., Zeuzem, S., Vargas, V., Saliba, F., Nevens, F., Alessandria, C., De Gottardi, A., Zoller, H., Ginès, P., Sauerbruch, T., Gerbes, A., Stauber, R. E., Bernardi, M., Angeli, P., Pavesi, M., Moreau, R., Clària, J., Jalan, R., Arroyo, V., (2019). Addressing profiles of systemic inflammation across the different clinical phenotypes of acutely decompensated cirrhosis Frontiers in Immunology 10, 476
Background: Patients with acutely decompensated cirrhosis (AD) may or may not develop acute-on-chronic liver failure (ACLF). ACLF is characterized by high-grade systemic inflammation, organ failures (OF) and high short-term mortality. Although patients with AD cirrhosis exhibit distinct clinical phenotypes at baseline, they have low short-term mortality, unless ACLF develops during follow-up. Because little is known about the association of profile of systemic inflammation with clinical phenotypes of patients with AD cirrhosis, we aimed to investigate a battery of markers of systemic inflammation in these patients.
Methods: Upon hospital admission baseline plasma levels of 15 markers (cytokines, chemokines, and oxidized albumin) were measured in 40 healthy controls, 39 compensated cirrhosis, 342 AD cirrhosis, and 161 ACLF. According to EASL-CLIF criteria, AD cirrhosis was divided into three distinct clinical phenotypes (AD-1: Creatinine<1.5, no HE, no OF; AD-2: creatinine 1.5–2, and or HE grade I/II, no OF; AD-3: Creatinine<1.5, no HE, non-renal OF).
Results: Most markers were slightly abnormal in compensated cirrhosis, but markedly increased in AD. Patients with ACLF exhibited the largest number of abnormal markers, indicating “full-blown” systemic inflammation (all markers). AD-patients exhibited distinct systemic inflammation profiles across three different clinical phenotypes. In each phenotype, activation of systemic inflammation was only partial (30% of the markers). Mortality related to each clinical AD-phenotype was significantly lower than mortality associated with ACLF (p < 0.0001 by gray test). Among AD-patients baseline systemic inflammation (especially IL-8, IL-6, IL-1ra, HNA2 independently associated) was more intense in those who had poor 28-day outcomes (ACLF, death) than those who did not experience these outcomes.
Conclusions: Although AD-patients exhibit distinct profiles of systemic inflammation depending on their clinical phenotypes, all these patients have only partial activation of systemic inflammation. However, those with the most extended baseline systemic inflammation had the highest the risk of ACLF development and death.
JTD Keywords: ACLF, Acute decompensation, Cirrhosis, Organ dysfunction, Organ failure, Signature
Alvarez-Silva, C., Schierwagen, R., Pohlmann, A., Magdaleno, F., Uschner, F. E., Ryan, P., Vehreschild, M. J. G. T., Claria, J., Latz, E., Lelouvier, B., Arumugam, M., Trebicka, J., (2019). Compartmentalization of immune response and microbial translocation in decompensated cirrhosis Frontiers in Immunology 10, 69
Background: Acquired dysfunctional immunity in cirrhosis predisposes patients to frequent bacterial infections, especially spontaneous bacterial peritonitis (SBP), leading to systemic inflammation that is associated with poor outcome. But systemic inflammation can also be found in the absence of a confirmed infection. Detection of bacterial DNA has been investigated as a marker of SBP and as a predictor of prognosis. Data is, however, contradictory. Here we investigated whether levels of IL-6 and IL-8 putatively produced by myeloid cells in ascites are associated with systemic inflammation and whether inflammation depends on the presence of specific bacterial DNA.
Methods and Materials: We enrolled 33 patients with decompensated liver cirrhosis from whom we collected paired samples of blood and ascites. IL-6 and IL-8 were measured in serum samples of all patients using ELISA. In a subset of 10 representative patients, bacterial DNA was extracted from ascites and whole blood, followed by 16S rRNA gene amplicon sequencing.
Results: There were significantly higher levels of IL-6 in ascites fluid compared to blood samples in all patients. Interestingly, IL-6 levels in blood correlated tightly with disease severity and surrogates of systemic inflammation, while IL-6 levels in ascites did not. Moreover, patients with higher blood CRP levels showed greater SBP prevalence compared to patients with lower levels, despite similar positive culture results. Bacterial richness was also significantly higher in ascites compared to the corresponding patient blood. We identified differences in microbial composition and diversity between ascites and blood, but no tight relationship with surrogates of systemic inflammation could be observed.
Discussion: In decompensated cirrhosis, markers of systemic inflammation and microbiota composition seem to be dysregulated in ascites and blood. While a relationship between systemic inflammation and microbiota composition seems to exist in blood, this is not the case for ascites in our hands. These data may suggest compartmentalization of the immune response and interaction of the latter with the microbiota especially in the blood compartment.
JTD Keywords: Acute-on-chronic liver failure, Ascites, Cirrhosis, Cytokines, Microbiome, Myeloid cells, Systemic inflammation
Noselli, G., Arroyo, M., DeSimone, A., (2019). Smart helical structures inspired by the pellicle of euglenids Journal of the Mechanics and Physics of Solids 123, 234-246
This paper deals with a concept for a reconfigurable structure bio-inspired by the cell wall architecture of euglenids, a family of unicellular protists, and based on the relative sliding of adjacent strips. Uniform sliding turns a cylinder resulting from the assembly of straight and parallel strips into a cylinder of smaller height and larger radius, in which the strips are deformed into a family of parallel helices. We examine the mechanics of this cylindrical assembly, in which the interlocking strips are allowed to slide freely at their junctions, and compute the external forces (axial force and axial torque at the two ends, or pressure on the lateral surface) necessary to drive and control the shape changes of the composite structure. Despite the simplicity of the structure, we find a remarkably complex mechanical behaviour that can be tuned by the spontaneous curvature or twist of the strips.
JTD Keywords: Bio-inspired structures, Euglenoid pellicle, Helical bundles, Morphing structures, Reconfigurable structures
Maier, Martina, Rubio Ballester, Belén, Duff, Armin, Duarte Oller, Esther, Verschure, P., (2019). Effect of specific over nonspecific VR-based rehabilitation on poststroke motor recovery: A systematic meta-analysis Neurorehabilitation and Neural Repair 33, (2), 112-129
Background. Despite the rise of virtual reality (VR)-based interventions in stroke rehabilitation over the past decade, no consensus has been reached on its efficacy. This ostensibly puzzling outcome might not be that surprising given that VR is intrinsically neutral to its use—that is, an intervention is effective because of its ability to mobilize recovery mechanisms, not its technology. As VR systems specifically built for rehabilitation might capitalize better on the advantages of technology to implement neuroscientifically grounded protocols, they might be more effective than those designed for recreational gaming. Objective. We evaluate the efficacy of specific VR (SVR) and nonspecific VR (NSVR) systems for rehabilitating upper-limb function and activity after stroke. Methods. We conducted a systematic search for randomized controlled trials with adult stroke patients to analyze the effect of SVR or NSVR systems versus conventional therapy (CT). Results. We identified 30 studies including 1473 patients. SVR showed a significant impact on body function (standardized mean difference [SMD] = 0.23; 95% CI = 0.10 to 0.36; P = .0007) versus CT, whereas NSVR did not (SMD = 0.16; 95% CI = −0.14 to 0.47; P = .30). This result was replicated in activity measures. Conclusions. Our results suggest that SVR systems are more beneficial than CT for upper-limb recovery, whereas NSVR systems are not. Additionally, we identified 6 principles of neurorehabilitation that are shared across SVR systems and are possibly responsible for their positive effect. These findings may disambiguate the contradictory results found in the current literature.
JTD Keywords: Stroke, Paresis, Virtual reality, Rehabilitation, Occupational therapy, Review
Lozano-García, M., Estrada-Petrocelli, L., Moxham, J., Rafferty, G. F., Torres, A., Jolley, C. J., Jané, R. , (2019). Noninvasive assessment of inspiratory muscle neuromechanical coupling during inspiratory threshold loading IEEE Access 7, 183634-183646
Diaphragm neuromechanical coupling (NMC), which reflects the efficiency of conversion of neural activation to transdiaphragmatic pressure (Pdi), is increasingly recognized to be a useful clinical index of diaphragm function and respiratory mechanics in neuromuscular weakness and cardiorespiratory disease. However, the current gold standard assessment of diaphragm NMC requires invasive measurements of Pdi and crural diaphragm electromyography (oesEMGdi), which complicates the measurement of diaphragm NMC in clinical practice. This is the first study to compare invasive measurements of diaphragm NMC (iNMC) using the relationship between Pdi and oesEMGdi, with noninvasive assessment of NMC (nNMC) using surface mechanomyography (sMMGlic) and electromyography (sEMGlic) of lower chest wall inspiratory muscles. Both invasive and noninvasive measurements were recorded in twelve healthy adult subjects during an inspiratory threshold loading protocol. A linear relationship between noninvasive sMMGlic and sEMGlic measurements was found, resulting in little change in nNMC with increasing inspiratory load. By contrast, a curvilinear relationship between invasive Pdi and oesEMGdi measurements was observed, such that there was a progressive increase in iNMC with increasing inspiratory threshold load. Progressive recruitment of lower ribcage muscles, serving to enhance the mechanical advantage of the diaphragm, may explain the more linear relationship between sMMGlic and sEMGlic (both representing lower intercostal plus costal diaphragm activity) than between Pdi and crural oesEMGdi. Noninvasive indices of NMC derived from sEMGlic and sMMGlic may prove to be useful indices of lower chest wall inspiratory muscle NMC, particularly in settings that do not have access to invasive measures of diaphragm function.
JTD Keywords: Cardiovascular system, Diaphragms, Diseases, Electromyography, Medical signal processing, Neurophysiology, Patient monitoring, Pneumodynamics, Inspiratory muscle neuromechanical coupling, Diaphragm neuromechanical coupling, Neural activation, Transdiaphragmatic pressure, Diaphragm function, Respiratory mechanics, Diaphragm NMC, Invasive measurements, Crural diaphragm electromyography, iNMC, Noninvasive assessment, nNMC, Lower chest wall inspiratory muscles, Inspiratory threshold loading protocol, Noninvasive sMMGlic measurements, sEMGlic measurements, oesEMGdi measurements, Inspiratory threshold load, Lower ribcage muscles, Lower intercostal plus costal diaphragm activity, Crural oesEMGdi, Noninvasive indices, sEMGlic sMMGlic, Lower chest wall inspiratory muscle NMC, Surface mechanomyography, Electromyography, Inspiratory threshold loading, Mechanomyography, Neuromechanical coupling, Respiratory muscles
Blanco-Almazan, D., Groenendaal, W., Catthoor, F., Jane, R., (2019). Wearable bioimpedance measurement for respiratory monitoring during inspiratory loading IEEE Access 7, 89487-89496
Bioimpedance is an unobtrusive noninvasive technique to measure respiration and has a linear relation with volume during normal breathing. The objective of this paper was to assess this linear relation during inspiratory loading protocol and determine the best electrode configuration for bioimpedance measurement. The inspiratory load is a way to estimate inspiratory muscle function and has been widely used in studies of respiratory mechanics. Therefore, this protocol permitted us to evaluate bioimpedance performance under breathing pattern changes. We measured four electrode configurations of bioimpedance and airflow simultaneously in ten healthy subjects using a wearable device and a standard wired laboratory acquisition system, respectively. The subjects were asked to perform an incremental inspiratory threshold loading protocol during the measurements. The load values were selected to increase progressively until the 60% of the subject's maximal inspiratory pressure. The linear relation of the signals was assessed by Pearson correlation (r ) and the waveform agreement by the mean absolute percentage error (MAPE), both computed cycle by cycle. The results showed a median greater than 0.965 in r coefficients and lower than 11 % in the MAPE values for the entire population in all loads and configurations. Thus, a strong linear relation was found during all loaded breathing and configurations. However, one out of the four electrode configurations showed robust results in terms of agreement with volume during the highest load. In conclusion, bioimpedance measurement using a wearable device is a noninvasive and a comfortable alternative to classical methods for monitoring respiratory diseases in normal and restrictive breathing.
JTD Keywords: Bioimpedance, Chronic respiratory diseases, Electrode configurations, Inspiratory threshold protocol, Wearable
Oliveira, V. R., Uriarte, J. J., Falcones, B., Jorba, I., Zin, W. A., Farré, R., Navajas, D., Almendros, I., (2019). Biomechanical response of lung epithelial cells to iron oxide and titanium dioxide nanoparticles Frontiers in Physiology 10, 1047
Increasing evidence shows that lungs can be damaged by inhalation of nanoparticles (NPs) at environmental and occupational settings. Recent findings have associated the exposure to iron oxide (Fe2O3) and titanium dioxide (TiO2) – NPs widely used in biomedical and clinical research – with pulmonary oxidative stress and inflammation. Although changes on cellular mechanics could contribute to pulmonary inflammation, there is no information regarding the effects of Fe2O3 and TiO2 on alveolar epithelial cell biomechanics. The aim was to investigate the NPs-induced biomechanical effects in terms of cell stiffness and traction forces exerted by human alveolar epithelial cells. Cell Young’s modulus (E) measured by atomic force microscopy in alveolar epithelial cells significantly decreased after exposure to Fe2O3 and TiO2 (-28 and -25%, respectively) compared to control conditions. Moreover, both NPs induced a similar reduction in the traction forces exerted by the alveolar epithelial cells in comparison to the control conditions. Accordingly, immunofluorescence images revealed a reduction of actomyosin stress fibers in response to the exposure to NPs. However, no inflammatory response was detected. In conclusion, an acute exposure of epithelial pulmonary cells to Fe2O3 and TiO2 NPs, which was mild since it was non-cytotoxic and did not induce inflammation, modified cell biomechanical properties which could be translated into damage of the epithelial barrier integrity, suggesting that mild environmental inhalation of Fe2O3 and TiO2 NPs could not be innocuous.
JTD Keywords: Actomyosin fibers, Air pollution, Cell biomechanics, Lung epithelium, Nanoparticles
Lozano-García, M., Estrada, L., Jané, R., (2019). Performance evaluation of fixed sample entropy in myographic signals for inspiratory muscle activity estimation Entropy 21, (2), 183
Fixed sample entropy (fSampEn) has been successfully applied to myographic signals for inspiratory muscle activity estimation, attenuating interference from cardiac activity. However, several values have been suggested for fSampEn parameters depending on the application, and there is no consensus standard for optimum values. This study aimed to perform a thorough evaluation of the performance of the most relevant fSampEn parameters in myographic respiratory signals, and to propose, for the first time, a set of optimal general fSampEn parameters for a proper estimation of inspiratory muscle activity. Different combinations of fSampEn parameters were used to calculate fSampEn in both non-invasive and the gold standard invasive myographic respiratory signals. All signals were recorded in a heterogeneous population of healthy subjects and chronic obstructive pulmonary disease patients during loaded breathing, thus allowing the performance of fSampEn to be evaluated for a variety of inspiratory muscle activation levels. The performance of fSampEn was assessed by means of the cross-covariance of fSampEn time-series and both mouth and transdiaphragmatic pressures generated by inspiratory muscles. A set of optimal general fSampEn parameters was proposed, allowing fSampEn of different subjects to be compared and contributing to improving the assessment of inspiratory muscle activity in health and disease.
JTD Keywords: Electromyography, Fixed sample entropy, Mechanomyography, Non-invasive physiological measurements, Oesophageal electromyography, Respiratory muscle
Oliveira, V. R., Uriarte, J. J., Falcones, B., Zin, W. A., Navajas, D., Farré, R., Almendros, I., (2019). Escherichia coli lipopolysaccharide induces alveolar epithelial cell stiffening Journal of Biomechanics 83, 315-318
Introduction: Application of lipopolysaccharide (LPS) is a widely employed model to mimic acute respiratory distress syndrome (ARDS). Available data regarding LPS-induced biomechanical changes on pulmonary epithelial cells are limited only to P. aeruginosa LPS. Considering that LPS from different bacteria could promote a specific mechanical response in epithelial cells, we aim to assess the effect of E. coli LPS, widely employed as a model of ARDS, in the biomechanics of alveolar epithelial cells.
Methods: Young’s modulus (E) of alveolar epithelial cells (A549) was measured by atomic force microscopy every 5 min throughout 60 min of experiment after treatment with LPS from E. coli (100 μg/mL). The percentage of cells presenting actin stress fibers (F-actin staining) was also evaluated. Control cells were treated with culture medium and the values obtained were compared with LPS-treated cells for each time-point.
Results: Application of LPS induced significant increase in E after 20 min (77%) till 60 min (104%) in comparison to controls. Increase in lung epithelial cell stiffness induced by LPS was associated with a higher number of cells presenting cytoskeletal remodeling.
Conclusions:
The observed effects of E. coli LPS on alveolar epithelial cells suggest that this widely-used LPS is able to promote a quick formation of actin stress fibers and stiffening cells, thereby facilitating the disruption of the pulmonary epithelial barrier.
JTD Keywords: Acute respiratory distress syndrome model, Alveolar epithelium, Biomechanics, E. coli, Lipopolysaccharide
Ballester, B. R., Maier, M., Duff, A., Cameirão, M., Bermúdez, S., Duarte, E., Cuxart, A., Rodríguez, S., San Segundo Mozo, R. M., Verschure, P., (2019). A critical time window for recovery extends beyond one-year post-stroke Journal of neurophysiology
Journal of Neurophysiology , 122, (1), 350-357
The impact of rehabilitation on post-stroke motor recovery and its dependency on the patient's chronicity remain unclear. The field has widely accepted the notion of a proportional recovery rule with a "critical window for recovery" within the first 3-6 mo poststroke. This hypothesis justifies the general cessation of physical therapy at chronic stages. However, the limits of this critical window have, so far, been poorly defined. In this analysis, we address this question, and we further explore the temporal structure of motor recovery using individual patient data from a homogeneous sample of 219 individuals with mild to moderate upper-limb hemiparesis. We observed that improvement in body function and structure was possible even at late chronic stages. A bootstrapping analysis revealed a gradient of enhanced sensitivity to treatment that extended beyond 12 mo poststroke. Clinical guidelines for rehabilitation should be revised in the context of this temporal structure. NEW & NOTEWORTHY Previous studies in humans suggest that there is a 3- to 6-mo "critical window" of heightened neuroplasticity poststroke. We analyze the temporal structure of recovery in patients with hemiparesis and uncover a precise gradient of enhanced sensitivity to treatment that expands far beyond the limits of the so-called critical window. These findings highlight the need for providing therapy to patients at the chronic and late chronic stages.
JTD Keywords: Motor recovery, Neuroplasticity, Neurorehabilitation, Stroke recovery, Virtual reality
Rubio Ballester, B., Mura, A., Maier, M., Tobella-Pareja, Laura, Alfayate-Domingo, D., Gimeno-Esteve, M. F., Aguilar, A., Verschure, P., (2019). Adaptive VR-based rehabilitation to prevent deterioration in adults with cerebral palsy Application of VR and Advanced Technology in Pediatric Populations
International Conference on Virtual Rehabilitation 2019 (ICVR 2019) , ISVR (Tel Aviv, Israel) , 1-7
Cerebral palsy (CP) is a disabling life-long condition progressively impeding a patient’s independence. Although incident rates are high, a clear understanding of the disease is missing. CP is characterized by several motor disorders and sensory or perceptive comorbidities. This multifaceted nature complicates proper diagnosis and hampers the search for possible treatments. During adolescence and adulthood, individuals with CP experience a drastic deterioration in gross motor control, independence, and quality of life. There is poor evidence that physical therapy promotes the retention of function through
aging, and no clinical studies exist that explore the potential of VRbased training to prevent deterioration. In this pilot randomized controlled trial, we expose 14 adults with CP to the Rehabilitation Gaming System (RGS) and examine its usability, effectiveness, and acceptability. Our results show that the RGS difficulty adaptation algorithm automatically matches the patients' impairment level as captured by clinical scales (Barthel and Box & Blocks). The clinical effectiveness and acceptability of the RGS and conventional therapy were comparable. We conclude that VR-based physical therapy as an adjunct to usual treatment may be a promising approach for the prevention of deterioration in adolescents and adults with CP.
JTD Keywords: Cerebral palsy, Virtual realitY, Motor function, Physical therapy, Rehabilitation
Ruiz, A. D., Mejía, J. S., López, J. M., Giraldo, B. F., (2019). Characterization of cardiac and respiratory system of healthy subjects in supine and sitting position Pattern Recognition and Image Analysis
ibPRIA 2019: Iberian Conference on Pattern Recognition and Image Analysis (Lecture Notes in Computer Science) , Springer, Cham (Madrid, Spain) 11867, 367-377
Studies based on the cardiac and respiratory system have allowed a better knowledge of their behavior to contribute with the diagnosis and treatment of diseases associated with them. The main goal of this project was to analyze the behavior of the cardiorespiratory system in healthy subjects, depending on the body position. The electrocardiography and respiratory flow signals were recorded in two positions, supine and sitting. Each signal was analyzed considering sliding windows of 30 s, with and overlapping of 50%. Temporal and spectral features were extracted from each signal. A total of 187 features were extracted for each window. According to statistical analysis, 148 features showed significant differences when comparing the position of the subject. Afterwards, the classifications methods based on decision trees, k-nearest neighbor and support vector machines were applied to identify the best classification model. The most advantageous performance model was obtained with a linear support vector machine method, with an accuracy of 99.5%, a sensitivity of 99.2% and a specificity of 99.6%. In conclusion, we have observed that the position of the body (supine or sitting) could modulate the cardiac and respiratory system response. New statistical models might provide new tools to analyze the behavior of these systems and the cardiorespiratory interaction complexity.
JTD Keywords: Cardiac dynamics, Respiratory dynamics, Statistical models, Supine and sitting posture
Arsiwalla, X. D., Freire, I. T., Vouloutsi, V., Verschure, P., (2019). Latent morality in algorithms and machines Biomimetic and Biohybrid Systems
8th International Conference, Living Machines 2019 (Lecture Notes in Computer Science) , Springer, Cham (Nara, Japan) 11556, 309-315
Can machines be endowed with morality? We argue that morality in the descriptive or epistemic sense can be extended to artificial systems. Following arguments from evolutionary game-theory, we identify two main ingredients required to operationalize this notion of morality in machines. The first, being a group theory of mind, and the second, being an assignment of valence. We make the case for the plausibility of these operations in machines without reference to any form of intentionality or consciousness. The only systems requirements needed to support the above two operations are autonomous goal-directed action and the ability to interact and learn from the environment. Following this we have outlined a theoretical framework based on conceptual spaces and valence assignments to gauge latent morality in autonomous machines and algorithms.
JTD Keywords: Autonomous systems, Ethics of algorithms, Goal-directed action, Philosophy of morality, Qualia, Theory of mind
Samitier, Josep, Correia, A., (2019). Biomimetic Nanotechnology for Biomedical Applications (NanoBio&Med 2018) Biomimetics MDPI
Emerging nanobiotechnologies can offer solutions to the current and future challenges in medicine. By covering topics from regenerative medicine, tissue engineering, drug delivery, bionanofabrication, and molecular biorecognition, this Special Issue aims to provide an update on the trends in nanomedicine and drug delivery using biomimetic approaches, and the development of novel biologically inspired devices for the safe and effective diagnosis, prevention, and treatment of disease.
JTD Keywords: Bioinspired nanotechnologies, Bionanofabrication, Bio-nano measurement and microscopy, Nanomaterials for biological and medical applications, Nanoassemblies, Nanostructured surfaces, Drug delivery, Nanobioelectronics, Integrated systems/nanobiosensors, Nanotoxicology, Graphene-based applications
Muro, Silvia, (2018). Alterations in cellular processes involving vesicular trafficking and implications in drug delivery Biomimetics 3, (3), 19
Endocytosis and vesicular trafficking are cellular processes that regulate numerous functions required to sustain life. From a translational perspective, they offer avenues to improve the access of therapeutic drugs across cellular barriers that separate body compartments and into diseased cells. However, the fact that many factors have the potential to alter these routes, impacting our ability to effectively exploit them, is often overlooked. Altered vesicular transport may arise from the molecular defects underlying the pathological syndrome which we aim to treat, the activity of the drugs being used, or side effects derived from the drug carriers employed. In addition, most cellular models currently available do not properly reflect key physiological parameters of the biological environment in the body, hindering translational progress. This article offers a critical overview of these topics, discussing current achievements, limitations and future perspectives on the use of vesicular transport for drug delivery applications.
JTD Keywords: Cellular vesicles, Vesicle fusion, Fission and intracellular trafficking, Drug delivery systems and nanomedicines, Transcytosis and endocytosis of drugs carriers, Disease effects on vesicular trafficking, Drug effects on vesicular trafficking, Role of the biological environment
García-Díaz, María, Birch, Ditlev, Wan, Feng, Mørck Nielsen, Hanne, (2018). The role of mucus as an invisible cloak to transepithelial drug delivery by nanoparticles Advanced Drug Delivery Reviews 124, 107-124
Mucosal administration of drugs and drug delivery systems has gained increasing interest. However, nanoparticles intended to protect and deliver drugs to epithelial surfaces require transport through the surface-lining mucus. Translation from bench to bedside is particularly challenging for mucosal administration since a variety of parameters will influence the specific barrier properties of the mucus including the luminal fluids, the microbiota, the mucus composition and clearance rate, and the condition of the underlying epithelia. Besides, after administration, nanoparticles interact with the mucosal components, forming a biomolecular corona that modulates their behavior and fate after mucosal administration. These interactions are greatly influenced by the nanoparticle properties, and therefore different designs and surface-engineering strategies have been proposed. Overall, it is essential to evaluate these biomolecule-nanoparticle interactions by complementary techniques using complex and relevant mucus barrier matrices.
JTD Keywords: Nanoparticle formulation strategies, Corona formation, Digestive tract, Respiratory tract, Luminal content, Methodologies, Analysis
Katuri, Jaideep, Caballero, David, Voituriez, R., Samitier, Josep, Sanchez, Samuel, (2018). Directed flow of micromotors through alignment interactions with micropatterned ratchets ACS Nano 12, (7), 7282-7291
To achieve control over naturally diffusive, out-of-equilibrium systems composed of self-propelled particles, such as cells or self-phoretic colloids, is a long-standing challenge in active matter physics. The inherently random motion of these active particles can be rectified in the presence of local and periodic asymmetric cues given that a non-trivial interaction exists between the self-propelled particle and the cues. Here, we exploit the phoretic and hydrodynamic interactions of synthetic micromotors with local topographical features to break the time-reversal symmetry of particle trajectories and to direct a macroscopic flow of micromotors. We show that the orientational alignment induced on the micromotors by the topographical features, together with their geometrical asymmetry, are crucial in generating directional particle flow. We also show that our system can be used to concentrate micromotors in confined spaces and identify the interactions responsible for this effect. Finally, we develop a minimal model which identifies the main parameters of the system responsible for the observed rectification. Overall, our system allows for robust control over both temporal and spatial distribution of synthetic micromotors.
JTD Keywords: Active colloids, Directional control, Janus particles, Micromotors, Self-propulsion
Pérez, Judit, Dulay, Samuel, Mir, M., Samitier, Josep, (2018). Molecular architecture for DNA wiring Biosensors and Bioelectronics 121, 54-61
Detection of the hybridisation events is of great importance in many different biotechnology applications such as diagnosis, computing, molecular bioelectronics, and among others. However, one important drawback is the low current of some redox reporters that limits their application. This paper demonstrates the powerful features of molecular wires, in particular the case of S-[4-[2-[4-(2-Phenylethynyl)phenyl]ethynyl]phenyl] thiol molecule and the key role that play the nanometric design of the capture probe linkers to achieve an efficient couple of the DNA complementary ferrocene label with the molecular wire for an effective electron transfer in co-immobilised self-assembled monolayers (SAMs) for DNA hybridisation detection. In this article, the length of the linker capture probe was studied for electron transfer enhancement from the ferrocene-motifs of immobilised molecules towards the electrode surface to obtain higher kinetics in the presence of thiolated molecular wires. The use of the right couple of capture probe linker and molecular wire has found to be beneficial as it helps to amplify eightfold the signal obtained.
JTD Keywords: DNA hybridisation, Bioelectronics, Electron transfer rate constant, Molecular wires, Electrochemistry, Ferrocene, Biosensor
Villa, Katherine, Parmar, Jemish, Vilela, Diana, Sánchez, Samuel, (2018). Metal-oxide-based microjets for the simultaneous removal of organic pollutants and heavy metals ACS Applied Materials and Interfaces 10, (24), 20478-20486
Water contamination from industrial and anthropogenic activities is nowadays a major issue in many countries worldwide. To address this problem, efficient water treatment technologies are required. Recent efforts have focused on the development of self-propelled micromotors that provide enhanced micromixing and mass transfer by the transportation of reactive species, resulting in higher decontamination rates. However, a real application of these micromotors is still limited due to the high cost associated to their fabrication process. Here, we present Fe2O3-decorated SiO2/MnO2 microjets for the simultaneous removal of industrial organic pollutants and heavy metals present in wastewater. These microjets were synthesized by low-cost and scalable methods. They exhibit an average speed of 485 ± 32 μm s–1 (∼28 body length per s) at 7% H2O2, which is the highest reported for MnO2-based tubular micromotors. Furthermore, the photocatalytic and adsorbent properties of the microjets enable the efficient degradation of organic pollutants, such as tetracycline and rhodamine B under visible light irradiation, as well as the removal of heavy metal ions, such as Cd2+ and Pb2+.
JTD Keywords: Micromotors, Photocatalytic, Water purification, Fenton, Magnetic control, Iron oxide, Manganese oxide
Raymond, Santiago, Maazouz, Yassine, Montufar, Edgar B., Perez, Roman A., González, Borja, Konka, Joanna, Kaiser, Jozef, Ginebra, Maria-Pau, (2018). Accelerated hardening of nanotextured 3D-plotted self-setting calcium phosphate inks Acta Biomaterialia 75, 451-462
Direct ink writing (DIW) techniques open up new possibilities for the fabrication of patient-specific bone grafts. Self-setting calcium phosphate inks, which harden at low temperature, allow obtaining nanostructured scaffolds with biomimetic properties and enhanced bioactivity. However, the slow hardening kinetics hampers the translation to the clinics. Different hydrothermal treatments for the consolidation of DIW scaffolds fabricated with an α-tricalcium phosphate /pluronic F127 ink were explored, comparing them with a biomimetic treatment. Three different scaffold architectures were analysed. The hardening process, associated to the conversion of α-tricalcium phosphate to hydroxyapatite was drastically accelerated by the hydrothermal treatments, reducing the time for complete reaction from 7 days to 30 minutes, while preserving the scaffold architectural integrity and retaining the nanostructured features. β-tricalcium phosphate was formed as a secondary phase, and a change of morphology from plate-like to needle-like crystals in the hydroxyapatite phase was observed. The binder was largely released during the treatment. The hydrothermal treatment resulted in a 30% reduction of the compressive strength, associated to the residual presence of β-tricalcium phosphate. Biomimetic and hydrothermally treated scaffolds supported the adhesion and proliferation of rat mesenchymal stem cells, indicating a good suitability for bone tissue engineering applications.
Statement of Significance: 3D plotting has opened up new perspectives in the bone regeneration field allowing the customisation of synthetic bone grafts able to fit patient-specific bone defects. Moreover, this technique allows the control of the scaffolds’ architecture and porosity. The present work introduces a new method to harden biomimetic hydroxyapatite 3D-plotted scaffolds which avoids high-temperature sintering. It has two main advantages: i) it is fast and simple, reducing the whole fabrication process from the several days required for the biomimetic processing to a few hours; and ii) it retains the nanostructured character of biomimetic hydroxyapatite and allows controlling the porosity from the nano- to the macroscale. Moreover, the good in vitro cytocompatibility results support its suitability for cell-based bone regeneration therapies.
JTD Keywords: Calcium phosphate, Hydroxyapatite, Biomimetic, Bone regeneration, 3D plotting, Direct ink writing, Bone graft
Garcia-Esparcia, P., Koneti, A., Rodríguez-Oroz, M. C., Gago, B., del Rio, J. A., Ferrer, Isidro, (2018). Mitochondrial activity in the frontal cortex area 8 and angular gyrus in Parkinson's disease and Parkinson's disease with dementia Brain Pathology 28, (1), 43-57
Altered mitochondrial function is characteristic in the substantia nigra in Parkinson's disease (PD). Information about mitochondria in other brain regions such as the cerebral cortex is conflicting mainly because most studies have not contemplated the possibility of variable involvement depending on the region, stage of disease progression and clinical symptoms such as the presence or absence of dementia. RT-qPCR of 18 nuclear mRNAs encoding subunits of mitochondrial complexes and 12 mRNAs encoding energy metabolism-related enzymes; western blotting of mitochondrial proteins; and analysis of enzymatic activities of complexes I, II, II, IV and V of the respiratory chain were assessed in frontal cortex area 8 and the angular gyrus of middle-aged individuals (MA), and those with incidental PD (iPD), long-lasting PD with parkinsonism without dementia (PD) and long-lasting PD with dementia (PDD). Up-regulation of several genes was found in frontal cortex area 8 in PD when compared with MA and in the angular gyrus in iPD when compared with MA. Marked down-regulation of genes encoding mitochondrial subunits and energy metabolism-related enzymes occurs in frontal cortex but only of genes coding for energy metabolism-related enzymes in the angular gyrus in PDD. Significant decrease in the protein expression levels of several mitochondrial subunits encoded by these genes occurs in frontal cortex area 8 and angular gyrus in PDD. Moreover, expression of MT-ND1 which is encoded by mitochondrial DNA is also reduced in PDD. Reduced enzymatic activity of complex III in frontal cortex area 8 and angular gyrus is observed in PD, but dramatic reduction in the activity of complexes I, II, II and IV in both regions characterizes PDD. Dementia in the context of PD is linked to region-specific deregulation of genomic genes encoding subunits of mitochondrial complexes and to marked reduction in the activity of mitochondrial complexes I, II, III and IV.
JTD Keywords: Cerebral cortex, Dementia, Energy metabolism, Incidental PD, Mitochondria, Oxidative phosphorylation, Parkinson disease, PDD, Respiratory chain
Badiola-Mateos, M., Hervera, A., del Río, J. A., Samitier, J., (2018). Challenges and future prospects on 3D in-vitro modeling of the neuromuscular circuit Frontiers in Bioengineering and Biotechnology 6, Article 194
Movement of skeletal-muscle fibers is generated by the coordinated action of several cells taking part within the locomotion circuit (motoneurons, sensory-neurons, Schwann cells, astrocytes, microglia, and muscle-cells). Failures in any part of this circuit could impede or hinder coordinated muscle movement and cause a neuromuscular disease (NMD) or determine its severity. Studying fragments of the circuit cannot provide a comprehensive and complete view of the pathological process. We trace the historic developments of studies focused on in-vitro modeling of the spinal-locomotion circuit and how bioengineered innovative technologies show advantages for an accurate mimicking of physiological conditions of spinal-locomotion circuit. New developments on compartmentalized microfluidic culture systems (cμFCS), the use of human induced pluripotent stem cells (hiPSCs) and 3D cell-cultures are analyzed. We finally address limitations of current study models and three main challenges on neuromuscular studies: (i) mimic the whole spinal-locomotion circuit including all cell-types involved and the evaluation of independent and interdependent roles of each one; (ii) mimic the neurodegenerative response of mature neurons in-vitro as it occurs in-vivo; and (iii) develop, tune, implement, and combine cμFCS, hiPSC, and 3D-culture technologies to ultimately create patient-specific complete, translational, and reliable NMD in-vitro model. Overcoming these challenges would significantly facilitate understanding the events taking place in NMDs and accelerate the process of finding new therapies.
JTD Keywords: 3D-culture, Compartmentalized microfluidic culture systems (cμFCS), HiPSC, In-vitro models, Neuromuscular circuit
Puigbò, J. Y., Maffei, G., Herreros, I., Ceresa, M., González Ballester, M. A., Verschure, P. F. M. J., (2018). Cholinergic behavior state-dependent mechanisms of neocortical gain control: A neurocomputational study Molecular Neurobiology 55, (1), 249-257
The embodied mammalian brain evolved to adapt to an only partially known and knowable world. The adaptive labeling of the world is critically dependent on the neocortex which in turn is modulated by a range of subcortical systems such as the thalamus, ventral striatum, and the amygdala. A particular case in point is the learning paradigm of classical conditioning where acquired representations of states of the world such as sounds and visual features are associated with predefined discrete behavioral responses such as eye blinks and freezing. Learning progresses in a very specific order, where the animal first identifies the features of the task that are predictive of a motivational state and then forms the association of the current sensory state with a particular action and shapes this action to the specific contingency. This adaptive feature selection has both attentional and memory components, i.e., a behaviorally relevant state must be detected while its representation must be stabilized to allow its interfacing to output systems. Here, we present a computational model of the neocortical systems that underlie this feature detection process and its state-dependent modulation mediated by the amygdala and its downstream target the nucleus basalis of Meynert. In particular, we analyze the role of different populations of inhibitory interneurons in the regulation of cortical activity and their state-dependent gating of sensory signals. In our model, we show that the neuromodulator acetylcholine (ACh), which is in turn under control of the amygdala, plays a distinct role in the dynamics of each population and their associated gating function serving the detection of novel sensory features not captured in the state of the network, facilitating the adjustment of cortical sensory representations and regulating the switching between modes of attention and learning.
JTD Keywords: Acetylcholine, Inhibitory network, Neocortical circuits, Neuromodulation
Estrada, L., Torres, A., Sarlabous, L., Jané, R., (2018). Onset and offset estimation of the neural inspiratory time in surface diaphragm electromyography: A pilot study in healthy subjects IEEE Journal of Biomedical and Health Informatics 22, (1), 67-76
This study evaluates the onset and offset of neural inspiratory time estimated from surface diaphragm electromyographic (EMGdi) recordings. EMGdi and airflow signals were recorded in ten healthy subjects according to two respiratory protocols based on respiratory rate (RR) increments, from 15 to 40 breaths per minute (bpm), and fractional inspiratory time (Ti/Ttot) decrements, from 0.54 to 0.18. The analysis of diaphragm electromyographic (EMGdi) signal amplitude is an alternative approach for the quantification of neural respiratory drive (NRD). The EMGdi amplitude was estimated using the fixed sample entropy computed over a 250 ms moving window of the EMGdi signal (EMGdifse). The neural onset was detected through a dynamic threshold over the EMGdifse using the kernel density estimation method, while neural offset was detected by finding when the EMGdifse had decreased to 70 % of the peak value reached during inspiration. The Bland-Altman analysis between airflow and neural onsets showed a global bias of 46 ms in the RR protocol and 22 ms in the Ti/Ttot protocol. The Bland-Altman analysis between airflow and neural offsets reveals a global bias of 11 ms in the RR protocol and -2 ms in the Ti/Ttot protocol. The relationship between pairs of RR values (Pearson’s correlation coefficient of 0.99, Bland- Altman limits of -2.39 to 2.41 bpm, and mean bias of 0.01 bpm) and between pairs of Ti/Ttot values (Pearson’s correlation coefficient of 0.86, Bland-Altman limits of -0.11 to 0.10, and mean bias of -0.01) showed a good agreement. In conclusion, we propose a method for determining neural onset and neural offset based on non-invasive recordings of the electrical activity of the diaphragm that requires no filtering of cardiac muscle interference.
JTD Keywords: Kernel density estimation (KDE),, Surface diaphragm electromyographic,, (EMGdi) signal,, Inspiratory time,, Neural respiratory drive (NRD),, Neural inspiratory time,, Fixed sample entropy (fSampEn)
Farré, Ramon, Otero, Jordi, Almendros, Isaac, Navajas, Daniel, (2018). Bioengineered lungs: A challenge and an opportunity Archivos de Bronconeumología 54, (1), 31-38
Lung biofabrication is a new tissue engineering and regenerative development aimed at providing organs for potential use in transplantation. Lung biofabrication is based on seeding cells into an acellular organ scaffold and on culturing them in an especial purpose bioreactor. The acellular lung scaffold is obtained by decellularizing a non-transplantable donor lung by means of conventional procedures based on application of physical, enzymatic and detergent agents. To avoid immune recipient's rejection of the transplanted bioengineered lung, autologous bone marrow/adipose tissue-derived mesenchymal stem cells, lung progenitor cells or induced pluripotent stem cells are used for biofabricating the bioengineered lung. The bioreactor applies circulatory perfusion and mechanical ventilation with physiological parameters to the lung during biofabrication. These physical stimuli to the organ are translated into the stem cell local microenvironment - e.g. shear stress and cyclic stretch - so that cells sense the physiological conditions in normally functioning mature lungs. After seminal proof of concept in a rodent model was published in 2010, the hypothesis that lungs can be biofabricated is accepted and intense research efforts are being devoted to the topic. The current experimental evidence obtained so far in animal tests and in ex vivo human bioengineered lungs suggests that the date of first clinical tests, although not immediate, is coming. Lung bioengineering is a disrupting concept that poses a challenge for improving our basic science knowledge and is also an opportunity for facilitating lung transplantation in future clinical translation.
JTD Keywords: Tissue engineering, Regenerative medicine, Lung transplantation, Lung repair, Lung regeneration
Marrugo-Ramírez, José, Mir, M., Samitier, Josep, (2018). Blood-based cancer biomarkers in liquid biopsy: A promising non-invasive alternative to tissue biopsy International Journal of Molecular Sciences 19, (10), 2877
Cancer is one of the greatest threats facing our society, being the second leading cause of death globally. Currents strategies for cancer diagnosis consist of the extraction of a solid tissue from the affected area. This sample enables the study of specific biomarkers and the genetic nature of the tumor. However, the tissue extraction is risky and painful for the patient and in some cases is unavailable in inaccessible tumors. Moreover, a solid biopsy is expensive and time consuming and cannot be applied repeatedly. New alternatives that overcome these drawbacks are rising up nowadays, such as liquid biopsy. A liquid biopsy is the analysis of biomarkers in a non-solid biological tissue, mainly blood, which has remarkable advantages over the traditional method; it has no risk, it is non-invasive and painless, it does not require surgery and reduces cost and diagnosis time. The most studied cancer non-invasive biomarkers are circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and exosomes. These circulating biomarkers play a key role in the understanding of metastasis and tumorigenesis, which could provide a better insight into the evolution of the tumor dynamics during treatment and disease progression. Improvements in isolation technologies, based on a higher grade of purification of CTCs, exosomes, and ctDNA, will provide a better characterization of biomarkers and give rise to a wide range of clinical applications, such as early detection of diseases, and the prediction of treatment responses due to the discovery of personalized tumor-related biomarkers
JTD Keywords: Liquid biopsy, Cancer, Biomarkers, Non-invasive, Circulant tumor DNA (ctDNA), Circulant tumor cells (CTC)
Silva, N., Riveros, A., Yutronic, N., Lang, E., Chornik, B., Guerrero, S., Samitier, J., Jara, P., Kogan, M. J., (2018). Photothermally controlled methotrexate release system using β-cyclodextrin and gold nanoparticles Nanomaterials 8, (12), 985
The inclusion compound (IC) of cyclodextrin (CD) containing the antitumor drug Methotrexate (MTX) as a guest molecule was obtained to increase the solubility of MTX and decrease its inherent toxic effects in nonspecific cells. The IC was conjugated with gold nanoparticles (AuNPs), obtained by a chemical method, creating a ternary intelligent delivery system for MTX molecules, based on the plasmonic properties of the AuNPs. Irradiation of the ternary system, with a laser wavelength tunable with the corresponding surface plasmon of AuNPs, causes local energy dissipation, producing the controlled release of the guest from CD cavities. Finally, cell viability was evaluated using MTS assays for β-CD/MTX and AuNPs + β-CD/MTX samples, with and without irradiation, against HeLa tumor cells. The irradiated sample of the ternary system AuNPs + β-CD/MTX produced a diminution in cell viability attributed to the photothermal release of MTX.
JTD Keywords: Cyclodextrin, Delivery system, Gold nanoparticles, Inclusion compound, Irradiation, Laser, Methotrexate, Photothermal release
Fonollosa, Jordi, Solórzano, Ana, Marco, Santiago, (2018). Chemical sensor systems and associated algorithms for fire detection: A review Sensors 18, (2), 553
Indoor fire detection using gas chemical sensing has been a subject of investigation since the early nineties. This approach leverages the fact that, for certain types of fire, chemical volatiles appear before smoke particles do. Hence, systems based on chemical sensing can provide faster fire alarm responses than conventional smoke-based fire detectors. Moreover, since it is known that most casualties in fires are produced from toxic emissions rather than actual burns, gas-based fire detection could provide an additional level of safety to building occupants. In this line, since the 2000s, electrochemical cells for carbon monoxide sensing have been incorporated into fire detectors. Even systems relying exclusively on gas sensors have been explored as fire detectors. However, gas sensors respond to a large variety of volatiles beyond combustion products. As a result, chemical-based fire detectors require multivariate data processing techniques to ensure high sensitivity to fires and false alarm immunity. In this paper, we the survey toxic emissions produced in fires and defined standards for fire detection systems. We also review the state of the art of chemical sensor systems for fire detection and the associated signal and data processing algorithms. We also examine the experimental protocols used for the validation of the different approaches, as the complexity of the test measurements also impacts on reported sensitivity and specificity measures. All in all, further research and extensive test under different fire and nuisance scenarios are still required before gas-based fire detectors penetrate largely into the market. Nevertheless, the use of dynamic features and multivariate models that exploit sensor correlations seems imperative
JTD Keywords: Fire detection, Gas sensor, Pattern recognition, Sensor fusion, Machine learning, Toxicants, Carbon monoxide, Hydrogen cyanide, Standard test fires, Transducers, Smoke
Truschzinski, M., Betella, A., Brunnett, G., Verschure, P., (2018). Emotional and cognitive influences in air traffic controller tasks: An investigation using a virtual environment? Applied Ergonomics 69, 1-9
Air traffic controllers are required to perform complex tasks which require attention and high precision. This study investigates how the difficulty of such tasks influences emotional states, cognitive workload and task performance. We use quantitative and qualitative measurements, including the recording of pupil dilation and changes in affect using questionnaires. Participants were required to perform a number of air traffic control tasks using the immersive human accessible Virtual Reality space in the "eXperience Induction Machine". Based on the data collected, we developed and validated a model which integrates personality, workload and affective theories. Our results indicate that the difficulty of an air traffic control task has a direct influence on cognitive workload as well as on the self-reported mood; whereas both mood and workload seem to change independently. In addition, we show that personality, in particular neuroticism, affects both mood and performance of the participants.
JTD Keywords: Air traffic control, Mood, Personality, Virtual reality, Workload
Pacheco, D., Verschure, P. F. M. J., (2018). Long-term spatial clustering in free recall Memory 26, (6), 798–806
We explored the influence of space on the organisation of items in long-term memory. In two experiments, we asked our participants to explore a virtual environment and memorise discrete items presented at specific locations. Memory for those items was later on tested in immediate (T1) and 24 hours delayed (T2) free recall tests, in which subjects were asked to recall as many items as possible in any order. In experiment 2, we further examined the contribution of active and passive navigation in recollection dynamics. Results across experiments revealed a significant tendency for participants to consecutively recall items that were encountered in proximate locations during learning. Moreover, the degree of spatial organisation and the total number of items recalled were positively correlated in the immediate and the delayed tests. Results from experiment 2 indicated that the spatial clustering of items was independent of navigation types. Our results highlight the long-term stability of spatial clustering effects and their correlation with recall performance, complementing previous results collected in immediate or briefly delayed tests.
JTD Keywords: Free recall, Spatial clustering, Spatial memory, Spatial navigation, Virtual reality
Verschure, P., (2018). The architecture of mind and brain
Living machines: A handbook of research in biomimetics and biohybrid systems (ed. Prescott, T. J., Lepora, Nathan, Verschure, P.), Oxford Scholarship (Oxford, UK) , 338-345
The components of a Living Machine must be integrated into a functioning whole, which requires a detailed understanding of the architecture of living machines. This chapter starts with a conceptual and historical analysis which from Plato brings us to nineteenth-century neuroscience and early concepts of the layered structure of nervous systems. These concepts were further captured in the cognitive behaviorism of Tolman and came to full fruition in the cognitive revolution of the second half of the twentieth century. Verschure subsequently describes the most relevant proposals of cognitive architectures followed by an overview of the few proposals stemming from modern neuroscience on the architecture of the brain. Subsequently, we will look at contemporary contenders that mediate between cognitive and brain architecture. An important challenge to any model of cognitive architectures is how to benchmark it. Verschure proposes the Unified Theories of Embodied Minds (UTEM) benchmark which advances from Newell’s classic Unified Theories of Cognition benchmark.
JTD Keywords: Architecture, Mind, Brain, Organization, System, Virtualization, Abstraction layers
Lepora, Nathan, Verschure, P., Prescott, T. J., (2018). A roadmap for Living Machines research
Living machines: A handbook of research in biomimetics and biohybrid systems (ed. Prescott, T. J., Lepora, Nathan, Verschure, P.), Oxford Scholarship (Oxford, UK) , 26-50
This roadmap identifies current trends in biomimetic and biohybrid systems together with their implications for future research and innovation. Important questions include the scale at which these systems are defined, the types of biological systems addressed, the kind of principles sought, the differences between biologically based and biologically inspired approaches, the role in the understanding of living systems, relevant application domains, common benchmarks, the relation to other fields, and developments on the horizon. We interviewed and collated answers from experts who have been involved a series of events organized by the Convergent Science Network. These answers were then collated into themes of research. Overall, we see a field rapidly expanding in influence and impact. As such, this report will provide information to researchers and scientific policy makers on contemporary biomimetics and its future, together with pointers to further reading on relevant topics within this handbook.
JTD Keywords: Biomimetics, Biohybrid, Bio-inspiration, Biologically inspired, Roadmap, Living machines, policy
Caballero, D., Palacios, L., Freitas, P. P., Samitier, J., (2017). An interplay between matrix anisotropy and actomyosin contractility regulates 3D-directed cell migration Advanced Functional Materials 27, (35), 1702322
Directed cell migration is essential for many biological processes, such as embryonic development or cancer progression. Cell contractility and adhesion to the extracellular matrix are known to regulate cell locomotion machinery. However, the cross-talk between extrinsic and intrinsic factors at the molecular level on the biophysical mechanism of three dimensional (3D)-directed cell migration is still unclear. In this work, a novel physiologically relevant in vitro model of the extracellular microenvironment is used to reveal how the topological anisotropy of the extracellular matrix synergizes with actomyosin contractility to modulate directional cell migration morphodynamics. This study shows that cells seeded on polarized 3D matrices display asymmetric protrusion morphodynamics and in-vivo-like phenotypes. It is found that matrix anisotropy significantly enhances cell directionality, but strikingly, not the invasion distance of cells. In Rho-inhibited cells, matrix anisotropy counteracts the lack of actomyosin-driven forces to stabilize cell directionality suggesting a myosin-II-independent mechanism for cell guidance. Finally, this study shows that on isotropic 3D environments, cell directionality is independent of actomyosin contractility. Altogether, this study provides novel quantitative data on the biomechanical regulation of directional cell motion and shows the important regulatory role of matrix anisotropy and actomyosin forces to guide cell migration in 3D microenvironments.
JTD Keywords: Anisotropy, Directed cell migration, Extracellular matrices, Migration modes, Three dimensional microenvironments
López-Martínez, Montserrat, Artés, Juan Manuel, Sarasso, Veronica, Carminati, Marco, Díez-Pérez, Ismael, Sanz, Fausto, Gorostiza, Pau, (2017). Differential electrochemical conductance imaging at the nanoscale Small 13, (36), 1700958
Electron transfer in proteins is essential in crucial biological processes. Although the fundamental aspects of biological electron transfer are well characterized, currently there are no experimental tools to determine the atomic-scale electronic pathways in redox proteins, and thus to fully understand their outstanding efficiency and environmental adaptability. This knowledge is also required to design and optimize biomolecular electronic devices. In order to measure the local conductance of an electrode surface immersed in an electrolyte, this study builds upon the current–potential spectroscopic capacity of electrochemical scanning tunneling microscopy, by adding an alternating current modulation technique. With this setup, spatially resolved, differential electrochemical conductance images under bipotentiostatic control are recorded. Differential electrochemical conductance imaging allows visualizing the reversible oxidation of an iron electrode in borate buffer and individual azurin proteins immobilized on atomically flat gold surfaces. In particular, this method reveals submolecular regions with high conductance within the protein. The direct observation of nanoscale conduction pathways in redox proteins and complexes enables important advances in biochemistry and bionanotechnology.
JTD Keywords: Differential electrochemical conductance, ECSTM, Electron transport pathway, Iron passivation, Redox metalloproteins
Aragonès, Albert C., Medina, Ernesto, Ferrer-Huerta, Miriam, Gimeno, Nuria, Teixidó, Meritxell, Palma, Julio L., Tao, Nongjian, Ugalde, Jesus M., Giralt, Ernest, Díez-Pérez, Ismael, Mujica, Vladimiro, (2017). Measuring the spin-polarization power of a single chiral molecule Small 13, (2), 1602519
Frau-Méndez, Margalida A., Fernández-Vega, Iván, Ansoleaga, Belén, Blanco, Rosa, Carmona, Margarita, Antonio del Rio, Jose, Zerr, Inga, Llorens, Franc, Zarranz, Juan José, Ferrer, Isidro, (2017). Fatal familial insomnia: Mitochondrial and protein synthesis machinery decline in the mediodorsal thalamus Brain Pathology 27, (1), 95-106
The expression of subunits of mitochondrial respiratory complexes and components of the protein synthesis machinery from the nucleolus to the ribosome was analyzed in the mediodorsal thalamus in seven cases of Fatal Familial Insomnia (FFI) compared with age-matched controls. NDUFB8 (complex I subunit), SDHB (complex II subunit), UQCRC2 (complex III subunit), COX2 (complex IV subunit) and ATP50 (complex V subunit) expression levels, as revealed by western blotting, were reduced in FFI. Voltage-dependent anion channel (VDAC) and ATP5H were also reduced due to the marked depopulation of neurons. In contrast, a marked increase in superoxide dismutase 2 (SOD2) was found in reactive astrocytes thus suggesting that astrocytes are key factors in oxidative stress responses. The histone-binding chaperones nucleolin and nucleoplasmin 3, and histone H3 di-methylated K9 were markedly reduced together with a decrease in the expression of protein transcription elongation factor eEF1A. These findings show severe impairment in the expression of crucial components of mitochondrial function and protein synthesis in parallel with neuron loss in mediodorsal thalamus at terminal stages of FFI. Therapeutic measures must be taken long before the appearance of clinical symptoms to prevent the devastating effects of FFI.
JTD Keywords: Fatal familial insomnia, Mitochondria, Protein synthesis, Mitochondrial respiratory chain, Nucleolus, Ribosome
Schieber, R., Lasserre, F., Hans, M., Fernández-Yagüe, M., Díaz-Ricart, M., Escolar, G., Ginebra, M. P., Mücklich, F., Pegueroles, M., (2017). Direct laser interference patterning of CoCr alloy surfaces to control endothelial cell and platelet response for cardiovascular applications Advanced Healthcare Materials 6, (19), 1700327
The main drawbacks of cardiovascular bare-metal stents (BMS) are in-stent restenosis and stent thrombosis as a result of an incomplete endothelialization after stent implantation. Nano- and microscale modification of implant surfaces is a strategy to recover the functionality of the artery by stimulating and guiding molecular and biological processes at the implant/tissue interface. In this study, cobalt-chromium (CoCr) alloy surfaces are modified via direct laser interference patterning (DLIP) in order to create linear patterning onto CoCr surfaces with different periodicities (≈3, 10, 20, and 32 μm) and depths (≈20 and 800 nm). Changes in surface topography, chemistry, and wettability are thoroughly characterized before and after modification. Human umbilical vein endothelial cells' adhesion and spreading are similar for all patterned and plain CoCr surfaces. Moreover, high-depth series induce cell elongation, alignment, and migration along the patterned lines. Platelet adhesion and aggregation decrease in all patterned surfaces compared to CoCr control, which is associated with changes in wettability and oxide layer characteristics. Cellular studies provide evidence of the potential of DLIP topographies to foster endothelialization without enhancement of platelet adhesion, which will be of high importance when designing new BMS in the future.
JTD Keywords: CoCr, Direct laser interference patterning, Endothelial cells, Linear surface pattern, Platelets
Bianchi, M. V., Awaja, F., Altankov, G., (2017). Dynamic adhesive environment alters the differentiation potential of young and ageing mesenchymal stem cells Materials Science and Engineering: C 78, 467-474
Engineering dynamic stem cell niche-like environment offers opportunity to obtain better control of the fate of stem cells. We identified, for the first time, that periodic changes in the adhesive environment of human adipose derived mesenchymal stem cells (ADSCs) alters dramatically their asymmetric division but not their ability for symmetric renewal. Hereby, we used smart thermo-responsive polymer (PNIPAM) to create a dynamic adhesive environment for ADSCs by applying periodic temperature cycles to perturb adsorbed adhesive proteins to substratum interaction. Cumulative population doubling time (CPDT) curves showed insignificant decline in the symmetric cell growth studied for up to 13th passages accompanied with small changes in the overall cell morphology and moderately declined fibronectin (FN) matrix deposition probably as a functional consequence of ADSCs ageing. However, a substantial alteration in the differentiation potential of ADSCs from both early and late passages (3rd and 14th, respectively) was found when the cells were switched to osteogenic differentiation conditions. This behavior was evidenced by the significantly altered alkaline phosphatase activity and Ca deposition (Alizarin red) assayed at 3, 14 and 21 day in comparison to the control samples of regular TC polystyrene processed under same temperature settings.
JTD Keywords: Cell ageing, Dynamic adhesive environment, Extracellular matrix, Mesenchymal stem cells, PNIPAM, Stem cell niche, Symmetric and asymmetric cell growth, Thermo-cycling, Thermo-responsive polymer
Fraioli, R., Tsimbouri, P. M., Fisher, L. E., Nobbs, A. H., Su, B., Neubauer, S., Rechenmacher, F., Kessler, H., Ginebra, M. P., Dalby, M. J., Manero, J. M., Mas-Moruno, C., (2017). Towards the cell-instructive bactericidal substrate: Exploring the combination of nanotopographical features and integrin selective synthetic ligands Scientific Reports 7, (1), 16363
Engineering the interface between biomaterials and tissues is important to increase implant lifetime and avoid failures and revision surgeries. Permanent devices should enhance attachment and differentiation of stem cells, responsible for injured tissue repair, and simultaneously discourage bacterial colonization; this represents a major challenge. To take first steps towards such a multifunctional surface we propose merging topographical and biochemical cues on the surface of a clinically relevant material such as titanium. In detail, our strategy combines antibacterial nanotopographical features with integrin selective synthetic ligands that can rescue the adhesive capacity of the surfaces and instruct mesenchymal stem cell (MSC) response. To this end, a smooth substrate and two different high aspect ratio topographies have been produced and coated either with an αvβ3-selective peptidomimetic, an α5β1-selective peptidomimetic, or an RGD/PHSRN peptidic molecule. Results showed that antibacterial effects of the substrates could be maintained when tested on pathogenic Pseudomonas aeruginosa. Further, functionalization increased MSC adhesion to the surfaces and the αvβ3-selective peptidomimetic-coated nanotopographies promoted osteogenesis. Such a dual physicochemical approach to achieve multifunctional surfaces represents a first step in the design of novel cell-instructive biomaterial surfaces.
JTD Keywords: Bioinspired materials, Biomaterials – cells
Campillo, N., Falcones, B., Montserrat, J. M., Gozal, D., Obeso, A., Gallego-Martin, T., Navajas, D., Almendros, I., Farré, R., (2017). Frequency and magnitude of intermittent hypoxia modulate endothelial wound healing in a cell culture model of sleep apnea
Journal of Applied Physiology , 123, (5), 1047-1054
Intermittent hypoxia (IH) has been implicated in the cardiovascular consequences of obstructive sleep apnea (OSA). However, the lack of suitable experimental systems has precluded assessment as to whether IH is detrimental, protective, or both for the endothelium. The aim of the work was to determine the effects of frequency and amplitude of IH oxygenation swings on aortic endothelial wound healing. Monolayers of human primary endothelial cells were wounded and subjected to constant oxygenation (1%, 4%, 13%, or 20% O2) or IH at different frequencies (0.6, 6, or 60 cycles/h) and magnitude ranges (13–4% O2 or 20–1% O2), using a novel well-controlled system, with wound healing being measured after 24 h. Cell monolayer repair was similar at 20% O2 and 13% O2, but was considerably increased (approximately twofold) in constant hypoxia at 4% O2. The magnitude and frequency of IH considerably modulated wound healing. Cycles ranging 13–4% O2 at the lowest frequency (0.6 cycles/h) accelerated endothelial wound healing by 102%. However, for IH exposures consisting of 20% to 1% O2 oscillations, wound closure was reduced compared with oscillation in the 13–4% range (by 74% and 44% at 6 cycles/h and 0.6 cycles/h, respectively). High-frequency IH patterns simulating severe OSA (60 cycles/h) did not significantly modify endothelial wound closure, regardless of the oxygenation cycle amplitude. In conclusion, the frequency and magnitude of hypoxia cycling in IH markedly alter wound healing responses and emerge as key factors determining how cells will respond in OSA. NEW & NOTEWORTHY Intermittent hypoxia (IH) induces cardiovascular consequences in obstructive sleep apnea (OSA) patients. However, the vast array of frequencies and severities of IH previously employed in OSA-related experimental studies has led to controversial results on the effects of IH. By employing an optimized IH experimental system here, we provide evidence that the frequency and magnitude of IH markedly alter human aortic endothelial wound healing, emerging as key factors determining how cells respond in OSA.
JTD Keywords: Sleep apnea, Repair, Endothelium, Hypoxia, Reoxygenation
Simmchen, Juliane, Baeza, Alejandro, Miguel-Lopez, Albert, Stanton, Morgan M., Vallet-Regi, Maria, Ruiz-Molina, Daniel, Sánchez, Samuel, (2017). Dynamics of novel photoactive AgCl microstars and their environmental applications ChemNanoMat 3, (1), 65-71
In the field of micromotors many efforts are taken to find a substitute for peroxide as fuel. While most approaches turn towards other toxic high energy chemicals such as hydrazine, we introduce an energy source that is widely used in nature: light. Light is an ideal source of energy and some materials, such as AgCl, have the inherent property to transform light energy for chemical processes, which can be used to achieve propulsion. In the case of silver chloride, one observed process after light exposure is surface modification which leads to the release of ions generating chemo-osmotic gradients. Here we present endeavours to use those processes to propel uniquely shaped micro objects of micro star morphology with a high surface to volume ratio, study their dynamics and present approaches to go towards real environmental applications.
JTD Keywords: Self-propellers, Silver chloride, Environmental applications, Photoactive colloids, Anti bacterial
Pacheco, D., Sánchez-Fibla, M., Duff, A., Verschure, P. F. M. J., (2017). A spatial-context effect in recognition memory Frontiers in Behavioral Neuroscience 11, Article 143
We designed a novel experiment to investigate the modulation of human recognition memory by environmental context. Human participants were asked to navigate through a four-arm Virtual Reality (VR) maze in order to find and memorize discrete items presented at specific locations in the environment. They were later on tested on their ability to recognize items as previously presented or new. By manipulating the spatial position of half of the studied items during the testing phase of our experiment, we could assess differences in performance related to the congruency of environmental information at encoding and retrieval. Our results revealed that spatial context had a significant effect on the quality of memory. In particular, we found that recognition performance was significantly better in trials in which contextual information was congruent as opposed to those in which it was different. Our results are in line with previous studies that have reported spatial-context effects in recognition memory, further characterizing their magnitude under ecologically valid experimental conditions.
JTD Keywords: Context effects, Recognition memory, Spatial behavior, Spatial memory and navigation, Virtual reality
Estrada, L., Torres, A., Sarlabous, L., Jané, R., (2017). Influence of parameter selection in fixed sample entropy of surface diaphragm electromyography for estimating respiratory activity Entropy 19, (9), 460
Fixed sample entropy (fSampEn) is a robust technique that allows the evaluation of inspiratory effort in diaphragm electromyography (EMGdi) signals, and has potential utility in sleep studies. To appropriately estimate respiratory effort, fSampEn requires the adjustment of several parameters. The aims of the present study were to evaluate the influence of the embedding dimension m, the tolerance value r, the size of the moving window, and the sampling frequency, and to establish recommendations for estimating the respiratory activity when using the fSampEn on surface EMGdi recorded for different inspiratory efforts. Values of m equal to 1 and r ranging from 0.1 to 0.64, and m equal to 2 and r ranging from 0.13 to 0.45, were found to be suitable for evaluating respiratory activity. fSampEn was less affected by window size than classical amplitude parameters. Finally, variations in sampling frequency could influence fSampEn results. In conclusion, the findings suggest the potential utility of fSampEn for estimating muscle respiratory effort in further sleep studies.
JTD Keywords: Fixed sample entropy (fSampEn), Non-invasive respiratory monitoring, Respiratory activity, Respiratory effort, Surface diaphragm electromyography
Schwab, S., Lehmann, J., Lutz, P., Jansen, C., Appenrodt, B., Lammert, F., Strassburg, C. P., Spengler, U., Nischalke, H. D., Trebicka, J., (2017). Influence of genetic variations in the SOD1 gene on the development of ascites and spontaneous bacterial peritonitis in decompensated liver cirrhosis
European Journal of Gastroenterology and Hepatology , 29, (7), 800-804
Background The balance between generation and elimination of reactive oxygen species by superoxide dismutase (SOD) is crucially involved in the pathophysiology of liver cirrhosis. Reactive oxygen species damage cells and induce inflammation/fibrosis, but also play a critical role in immune defense from pathogens. As both processes are involved in the development of liver cirrhosis and its complications, genetic variation of the SOD1 gene was investigated. Patients and methods Two SOD1 single nucleotide polymorphisms (rs1041740 and rs3844942) were analyzed in 49 cirrhotic patients undergoing liver transplantation. In addition, 344 cirrhotic patients with ascites were analyzed in a cohort of 521 individuals in terms of the relationship of these polymorphisms with spontaneous bacterial peritonitis (SBP). Results Although rs3844942 showed no associations with complications of cirrhosis, we observed a significant association between rs1041740 and the presence of ascites and SBP in the discovery cohort of patients with cirrhosis. Importantly, the association with SBP was not confirmed in the validation cohort of patients with ascites. By contrast, a trend toward lower SBP rates was observed in carriers of rs1041740. In this cohort, rs1041740 was not associated with survival. Conclusion These data suggest a complex role of SOD1 in different processes leading to complications of liver cirrhosis. rs1041740 might be associated with the development of ascites and possibly plays a role in SBP once ascites has developed.
JTD Keywords: Ascites, Genetic polymorphism, Liver cirrhosis, Reactive oxygen stress, Spontaneous bacterial peritonitis, Superoxide dismutases
Garde, A., Sörnmo, L., Laguna, P., Jané, R., Benito, S., Bayés-Genís, A., Giraldo, B. F., (2017). Assessment of respiratory flow cycle morphology in patients with chronic heart failure
Medical and Biological Engineering and Computing , 55, (2), 245-255
Breathing pattern as periodic breathing (PB) in chronic heart failure (CHF) is associated with poor prognosis and high mortality risk. This work investigates the significance of a number of time domain parameters for characterizing respiratory flow cycle morphology in patients with CHF. Thus, our primary goal is to detect PB pattern and identify patients at higher risk. In addition, differences in respiratory flow cycle morphology between CHF patients (with and without PB) and healthy subjects are studied. Differences between these parameters are assessed by investigating the following three classification issues: CHF patients with PB versus with non-periodic breathing (nPB), CHF patients (both PB and nPB) versus healthy subjects, and nPB patients versus healthy subjects. Twenty-six CHF patients (8/18 with PB/nPB) and 35 healthy subjects are studied. The results show that the maximal expiratory flow interval is shorter and with lower dispersion in CHF patients than in healthy subjects. The flow slopes are much steeper in CHF patients, especially for PB. Both inspiration and expiration durations are reduced in CHF patients, mostly for PB. Using the classification and regression tree technique, the most discriminant parameters are selected. For signals shorter than 1 min, the time domain parameters produce better results than the spectral parameters, with accuracies for each classification of 82/78, 89/85, and 91/89 %, respectively. It is concluded that morphologic analysis in the time domain is useful, especially when short signals are analyzed.
JTD Keywords: Chronic heart failure, Ensemble average, Periodic and non-periodic breathing, Respiratory pattern
Solorzano, A., Fonollosa, J., Fernandez, L., Eichmann, J., Marco, S., (2017). Fire detection using a gas sensor array with sensor fusion algorithms IEEE Conference Publications
ISOCS/IEEE International Symposium on Olfaction and Electronic Nose (ISOEN) , IEEE (Montreal, Canada) , 1-3
Conventional fire alarms are based on smoke detection. Nevertheless, in some fire scenarios volatiles are released before smoke. Fire detectors based only on chemical sensors have already been proposed as they may provide faster response, but they are still prone to false alarms in the presence of nuisances. These systems rely heavily on pattern recognition techniques to discriminate fires from nuisances. In this context, it is important to test the systems according to international standards for fires and testing the system against a diversity of nuisances. In this work, we investigate the behavior of a gas sensor array coupled to sensor fusion algorithms for fire detection when exposed to standardized fires and several nuisances. Results confirmed the ability to detect fires (97% Sensitivity), although the system still produces a significant rate of false alarms (35%) for nuisances not presented in the training set.
JTD Keywords: Fire alarm, Gas sensor array, Machine Olfaction, Multisensor system, Sensor fusion
Quadri, M., Matera, C., Silnovi, Pismataro, M. C., Horenstein, N. A., Stokes, C., Papke, R. L., Dallanoce, C., (2017). Identification of α7 nicotinic acetylcholine receptor silent agonists based on the spirocyclic quinuclidine-Δ2-isoxazoline scaffold: Synthesis and electrophysiological evaluation ChemMedChem
XXIV National Meeting in Medicinal Chemistry (NMMC 2016) , Wiley Online Library (Perugia, Spain) 12, (16), 1335-1348
Compound 11 (3-(benzyloxy)-1′-methyl-1′-azonia-4H-1′-azaspiro[isoxazole-5,3′-bicyclo[2.2.2]octane] iodide) was selected from a previous set of nicotinic ligands as a suitable model compound for the design of new silent agonists of α7 nicotinic acetylcholine receptors (nAChRs). Silent agonists evoke little or no channel activation but can induce the α7 desensitized Ds state, which is sensitive to a type II positive allosteric modulator, such as PNU-120596. Introduction of meta substituents into the benzyloxy moiety of 11 led to two sets of tertiary amines and quaternary ammonium salts based on the spirocyclic quinuclidinyl-Δ2-isoxazoline scaffold. Electrophysiological assays performed on Xenopus laevis oocytes expressing human α7 nAChRs highlighted four compounds that are endowed with a significant silent-agonism profile. Structure–activity relationships of this group of analogues provided evidence of the crucial role of the positive charge at the quaternary quinuclidine nitrogen atom. Moreover, the present study indicates that meta substituents, in particular halogens, on the benzyloxy substructure direct specific interactions that stabilize a desensitized conformational state of the receptor and induce silent activity
JTD Keywords: Agonists, Cycloaddition, Nitrogen heterocycles, Receptors, Spiro compounds
Vila, M., García, A., Girotti, A., Alonso, M., Rodríguez-Cabello, J. C., González-Vázquez, A., Planell, J. A., Engel, E., Buján, J., Garcíaa-Honduvilla, N., Vallet-Regí, M., (2016). 3D silicon doped hydroxyapatite scaffolds decorated with Elastin-like Recombinamers for bone regenerative medicine Acta Biomaterialia 45, 349-356
The current study reports on the manufacturing by rapid prototyping technique of three-dimensional (3D) scaffolds based on silicon substituted hydroxyapatite with Elastin-like Recombinamers (ELRs) functionalized surfaces. Silicon doped hydroxyapatite (Si-HA), with Ca10(PO4)5.7(SiO4)0.3(OH)1.7h0.3 nominal formula, was surface functionalized with two different types of polymers designed by genetic engineering: ELR-RGD that contain cell attachment specific sequences and ELR-SNA15/RGD with both hydroxyapatite and cells domains that interact with the inorganic phase and with the cells, respectively. These hybrid materials were subjected to in vitro assays in order to clarify if the ELRs coating improved the well-known biocompatible and bone regeneration properties of calcium phosphates materials. The in vitro tests showed that there was a total and homogeneous colonization of the 3D scaffolds by Bone marrow Mesenchymal Stromal Cells (BMSCs). In addition, the BMSCs were viable and able to proliferate and differentiate into osteoblasts. Statement of Significance Bone tissue engineering is an area of increasing interest because its main applications are directly related to the rising life expectancy of the population, which promotes higher rates of several bone pathologies, so innovative strategies are needed for bone tissue regeneration therapies. Here we use the rapid prototyping technology to allow moulding ceramic 3D scaffolds and we use different bio-polymers for the functionalization of their surfaces in order to enhance the biological response. Combining the ceramic material (silicon doped hydroxyapatite, Si-HA) and the Elastin like Recombinamers (ELRs) polymers with the presence of the integrin-mediate adhesion domain alone or in combination with SNA15 peptide that possess high affinity for hydroxyapatite, provided an improved Bone marrow Mesenchymal Stromal Cells (BMSCs) differentiation into osteoblastic linkage.
JTD Keywords: Bone marrow Mesenchymal Stromal Cells (BMSCs), Bone repair, Elastin-like Recombinamers (ELRs), Rapid prototyped 3D scaffolds, Silicon doped hydroxyapatite (Si-HA), Tissue engineering
Fonollosa, J., Fernández, L., Gutiérrez-Gálvez, A., Huerta, R., Marco, S., (2016). Calibration transfer and drift counteraction in chemical sensor arrays using Direct Standardization Sensors and Actuators B: Chemical 236, 1044-1053
Inherent variability of chemical sensors makes it necessary to calibrate chemical detection systems individually. This shortcoming has traditionally limited usability of systems based on metal oxide gas sensor arrays and prevented mass-production for some applications. Here, aiming at exploring calibration transfer between chemical sensor arrays, we exposed five twin 8-sensor detection units to different concentration levels of ethanol, ethylene, carbon monoxide, or methane. First, we built calibration models using data acquired with a master unit. Second, to explore the transferability of the calibration models, we used Direct Standardization to map the signals of a slave unit to the space of the master unit in calibration. In particular, we evaluated the transferability of the calibration models to other detection units, and within the same unit measuring days apart. Our results show that signals acquired with one unit can be successfully mapped to the space of a reference unit. Hence, calibration models trained with a master unit can be extended to slave units using a reduced number of transfer samples, diminishing thereby calibration costs. Similarly, signals of a sensing unit can be transformed to match sensor behavior in the past to mitigate drift effects. Therefore, the proposed methodology can reduce calibration costs in mass-production and delay recalibrations due to sensor aging. Acquired dataset is made publicly available.
JTD Keywords: Calibration transfer, Chemical sensors, Direct Standardization, Electronic nose, MOX sensors, Public dataset
Lozano-Garcia, M., Fiz, J. A., Jané, R., (2016). Automatic differentiation of normal and continuous adventitious respiratory sounds using ensemble empirical mode decomposition and instantaneous frequency IEEE Journal of Biomedical and Health Informatics 20, (2), 486-497
Differentiating normal from adventitious respiratory sounds (RS) is a major challenge in the diagnosis of pulmonary diseases. Particularly, continuous adventitious sounds (CAS) are of clinical interest because they reflect the severity of certain diseases. This study presents a new classifier that automatically distinguishes normal sounds from CAS. It is based on the multi-scale analysis of instantaneous frequency (IF) and envelope (IE) calculated after ensemble empirical mode decomposition (EEMD). These techniques have two major advantages over previous techniques: high temporal resolution is achieved by calculating IF-IE and a priori knowledge of signal characteristics is not required for EEMD. The classifier is based on the fact that the IF dispersion of RS signals markedly decreases when CAS appear in respiratory cycles. Therefore, CAS were detected by using a moving window to calculate the dispersion of IF sequences. The study dataset contained 1494 RS segments extracted from 870 inspiratory cycles recorded from 30 patients with asthma. All cycles and their RS segments were previously classified as containing normal sounds or CAS by a highly experienced physician to obtain a gold standard classification. A support vector machine classifier was trained and tested using an iterative procedure in which the dataset was randomly divided into training (65%) and testing (35%) sets inside a loop. The SVM classifier was also tested on 4592 simulated CAS cycles. High total accuracy was obtained with both recorded (94.6% ± 0.3%) and simulated (92.8% ± 3.6%) signals. We conclude that the proposed method is promising for RS analysis and classification.
JTD Keywords: Diseases, Dispersion, Empirical mode decomposition, Feature extraction, Informatics, Support vector machines
Estrada, L., Torres, A., Sarlabous, L., Jané, R., (2016). Improvement in neural respiratory drive estimation from diaphragm electromyographic signals using fixed sample entropy IEEE Journal of Biomedical and Health Informatics 20, (2), 476-485
Diaphragm electromyography is a valuable technique for the recording of electrical activity of the diaphragm. The analysis of diaphragm electromyographic (EMGdi) signal amplitude is an alternative approach for the quantification of neural respiratory drive (NRD). The EMGdi signal is, however, corrupted by electrocardiographic (ECG) activity, and this presence of cardiac activity can make the EMGdi interpretation more difficult. Traditionally, the EMGdi amplitude has been estimated using the average rectified value (ARV) and the root mean square (RMS). In this work, surface EMGdi signals were analyzed using the fixed sample entropy (fSampEn) algorithm, and compared to traditional ARV and RMS methods. The fSampEn is calculated using a tolerance value fixed and independent of the standard deviation of the analysis window. Thus, this method quantifies the amplitude of the complex components of stochastic signals (such as EMGdi), and being less affected by changes in amplitude due to less complex components (such as ECG). The proposed method was tested in synthetic and recorded EMGdi signals. fSampEn was less sensitive to the effect of cardiac activity on EMGdi signals with different levels of NRD than ARV and RMS amplitude parameters. The mean and standard deviation of the Pearson’s correlation values between inspiratory mouth pressure (an indirect measure of the respiratory muscle activity) and fSampEn, ARV and RMS parameters, estimated in the recorded EMGdi signal at tidal volume (without inspiratory load), were 0.38???0.12, 0.27???0.11 and 0.11???0.13, respectively. Whereas at 33 cmH2O (maximum inspiratory load) were 0.83???0.02, 0.76???0.07 and 0.61???0.19, respectively. Our findings suggest that the proposed method may improve the evaluation of NRD.
JTD Keywords: Electromyography, diaphragm muscle, neural respiratory drive
Tahirbegi, I.B., Pardo, W.A., Alvira, M., Mir, M., Samitier, J., (2016). Amyloid Aβ 42, a promoter of magnetite nanoparticle formation in Alzheimer's disease Nanotechnology 27, (46), 465102
The accumulation of iron oxides - mainly magnetite - with amyloid peptide is a key process in the development of Alzheimer's disease (AD). However, the mechanism for biogeneration of magnetite inside the brain of someone with AD is still unclear. The iron-storing protein ferritin has been identified as the main magnetite-storing molecule. However, accumulations of magnetite in AD are not correlated with an increase in ferritin, leaving this question unresolved. Here we demonstrate the key role of amyloid peptide Aβ 42, one of the main hallmarks of AD, in the generation of magnetite nanoparticles in the absence of ferritin. The capacity of amyloid peptide to bind and concentrate iron hydroxides, the basis for the formation of magnetite, benefits the spontaneous synthesis of these nanoparticles, even under unfavorable conditions for their formation. Using scanning and transmission electron microscopy, electron energy loss spectroscopy and magnetic force microscopy we characterized the capacity of amyloid peptide Aβ 42 to promote magnetite formation.
JTD Keywords: Alzheimer disease (AD), amyloid peptide Ab42, magnetite nanoparticle, metallobiomolecule, iron oxide, neurodegenerative brain diseases
Farré, R., Navajas, D., (2016). Forced oscillation: A poorly exploited tool for simply assessing respiratory function in children
Respirology , 21, (6), 982-983
Lozano-Garcia, M., Fiz, J. A., Jané, R., (2016). Performance evaluation of the Hilbert–Huang transform for respiratory sound analysis and its application to continuous adventitious sound characterization
Signal Processing , 120, 99-116
Abstract The use of the Hilbert–Huang transform in the analysis of biomedical signals has increased during the past few years, but its use for respiratory sound (RS) analysis is still limited. The technique includes two steps: empirical mode decomposition (EMD) and instantaneous frequency (IF) estimation. Although the mode mixing (MM) problem of EMD has been widely discussed, this technique continues to be used in many RS analysis algorithms. In this study, we analyzed the MM effect in RS signals recorded from 30 asthmatic patients, and studied the performance of ensemble EMD (EEMD) and noise-assisted multivariate EMD (NA-MEMD) as means for preventing this effect. We propose quantitative parameters for measuring the size, reduction of MM, and residual noise level of each method. These parameters showed that EEMD is a good solution for MM, thus outperforming NA-MEMD. After testing different IF estimators, we propose Kay׳s method to calculate an EEMD-Kay-based Hilbert spectrum that offers high energy concentrations and high time and high frequency resolutions. We also propose an algorithm for the automatic characterization of continuous adventitious sounds (CAS). The tests performed showed that the proposed EEMD-Kay-based Hilbert spectrum makes it possible to determine CAS more precisely than other conventional time-frequency techniques.
JTD Keywords: Hilbert–Huang transform, Ensemble empirical mode decomposition, Instantaneous frequency, Respiratory sounds, Continuous adventitious sounds
Huerta, R., Mosqueiro, T., Fonollosa, J., Rulkov, N.F., Rodríguez-Lujan, I., (2016). Online decorrelation of humidity and temperature in chemical sensors for continuous monitoring
Chemometrics and Intelligent Laboratory Systems , 157, 169-176
A method for online decorrelation of chemical sensor signals from the effects of environmental humidity and temperature variations is proposed. The goal is to improve the accuracy of electronic nose measurements for continuous monitoring by processing data from simultaneous readings of environmental humidity and temperature. The electronic nose setup built for this study included eight metal-oxide sensors, temperature and humidity sensors with a wireless communication link to external computer. This wireless electronic nose was used to monitor the air for two years in the residence of one of the authors and it collected data continuously during 537 days with a sampling rate of 1 sample per second. To estimate the effects of variations in air humidity and temperature on the chemical sensors' signals, we used a standard energy band model for an n-type metal-oxide (MOX) gas sensor. The main assumption of the model is that variations in sensor conductivity can be expressed as a nonlinear function of changes in the semiconductor energy bands in the presence of external humidity and temperature variations. Fitting this model to the collected data, we confirmed that the most statistically significant factors are humidity changes and correlated changes of temperature and humidity. This simple model achieves excellent accuracy with a coefficient of determination R2 close to 1. To show how the humidity–temperature correction model works for gas discrimination, we constructed a model for online discrimination among banana, wine and baseline response. This shows that pattern recognition algorithms improve performance and reliability by including the filtered signal of the chemical sensors.
JTD Keywords: Electronic nose, Chemical sensors, Humidity, Temperature, Decorrelation, Wireless e-nose, MOX sensors, Energy band model, Home monitoring
Estrada, L., Torres, A., Sarlabous, L., Jané, R., (2016). Evaluating respiratory muscle activity using a wireless sensor platform Engineering in Medicine and Biology Society (EMBC)
38th Annual International Conference of the IEEE , IEEE (Orlando, USA) , 5769-5772
Wireless sensors are an emerging technology that allows to assist physicians in the monitoring of patients health status. This approach can be used for the non-invasive recording of the electrical respiratory muscle activity of the diaphragm (EMGdi). In this work, we acquired the EMGdi signal of a healthy subject performing an inspiratory load test. To this end, the EMGdi activity was captured from a single channel of electromyography using a wireless platform which was compared with the EMGdi and the inspiratory mouth pressure (Pmouth) recorded with a conventional lab equipment. From the EMGdi signal we were able to evaluate the neural respiratory drive, a biomarker used for assessing the respiratory muscle function. In addition, we evaluated the breathing movement and the cardiac activity, estimating two cardio-respiratory parameters: the respiratory rate and the heart rate. The correlation between the two EMGdi signals and the Pmouth improved with increasing the respiratory load (Pearson's correlation coefficient ranges from 0.33 to 0.85). The neural respiratory drive estimated from both EMGdi signals showed a positive trend with an increase of the inspiratory load and being higher in the conventional EMGdi recording. The respiratory rate comparison between measurements revealed similar values of around 16 breaths per minute. The heart rate comparison showed a root mean error of less than 0.2 beats per minute which increased when incrementing the inspiratory load. In summary, this preliminary work explores the use of wireless devices to record the muscle respiratory activity to derive several physiological parameters. Its use can be an alternative to conventional measuring systems with the advantage of being portable, lightweight, flexible and operating at low energy. This technology can be attractive for medical staff and may have a positive impact in the way healthcare is being delivered.
JTD Keywords: Biomedical monitoring, Electrodes, Medical services, Monitoring, Muscles, Wireless communication, Wireless sensor networks
Ziyatdinov, Andrey, Fonollosa, Jordi, Fernández, Luis, Gutiérrez-Gálvez, Agustín, Marco, Santiago, Perera, Alexandre, (2015). Data set from gas sensor array under flow modulation Data in Brief 3, 131-136
Abstract Recent studies in neuroscience suggest that sniffing, namely sampling odors actively, plays an important role in olfactory system, especially in certain scenarios such as novel odorant detection. While the computational advantages of high frequency sampling have not been yet elucidated, here, in order to motivate further investigation in active sampling strategies, we share the data from an artificial olfactory system made of 16 MOX gas sensors under gas flow modulation. The data were acquired on a custom set up featured by an external mechanical ventilator that emulates the biological respiration cycle. 58 samples were recorded in response to a relatively broad set of 12 gas classes, defined from different binary mixtures of acetone and ethanol in air. The acquired time series show two dominant frequency bands: the low-frequency signal corresponds to a conventional response curve of a sensor in response to a gas pulse, and the high-frequency signal has a clear principal harmonic at the respiration frequency. The data are related to the study in [1], and the data analysis results reported there should be considered as a reference point.
JTD Keywords: Gas sensor array, MOX sensor, Flow modulation, Early detection, Biomimetics, Respiration, Sniffing
Galán, T., Prieto-Simón, B., Alvira, M., Eritja, R., Götz, G., Bäuerle, P., Samitier, J., (2015). Label-free electrochemical DNA sensor using "click"-functionalized PEDOT electrodes Biosensors and Bioelectronics 74, 751-756
Here we describe a label-free electrochemical DNA sensor based on poly(3,4-ethylenedioxythiophene)-modified (PEDOT-modified) electrodes. An acetylene-terminated DNA probe, complementary to a specific "Hepatitis C" virus sequence, was immobilized onto azido-derivatized conducting PEDOT electrodes using "click" chemistry. DNA hybridization was then detected by differential pulse voltammetry, evaluating the changes in the electrochemical properties of the polymer produced by the recognition event. A limit of detection of 0.13. nM was achieved using this highly selective PEDOT-based genosensor, without the need for labeling techniques or microelectrode fabrication processes. These results are promising for the development of label-free and reagentless DNA hybridization sensors based on conducting polymeric substrates. Biosensors can be easily prepared using any DNA sequence containing an alkyne moiety. The data presented here reveal the potential of this DNA sensor for diagnostic applications in the screening of diseases, such as "Hepatitis C", and genetic mutations.
JTD Keywords: Azido-EDOT, Click chemistry, Differential pulse voltammetry, DNA biosensor, Electrochemistry, Hepatitis C virus
Ponce, I., Aragonès, A. C., Darwish, Nadrim, Pla-Vilanova, P., Oñate, R., Rezende, M. C., Zagal, J. H., Sanz, F., Pavez, J., Díez-Pérez, I., (2015). Building nanoscale molecular wires exploiting electrocatalytic interactions Electrochimica Acta 179, 611-167
Herein, we present a novel method to design nanoscale molecular wires by exploiting well-established electrocatalytic molecular platforms based on metallophthalocyanine blocks. Metallophthalocyanines exhibit high catalytic activity for a wide variety of electrochemical reactions of practical interests. To this aim, metallophthalocyanine molecules can be attached to an electrode surface via a conjugated mercaptopyridine axial ligand that provides (i) stable chemical binding to the metal surface through the thiol-anchoring group, and (ii) a good electrical communication between the metallophthalocyanine ring and the electrode surface. Our previous work demonstrates that long mercaptopyridinium blocks act as excellent linkers in such electrocatalytic platform, resulting in an optimal electrocatalytic activity of the metallophthalocyanine unit. Here we profit from this optimized electrocatalytic molecular platform to design new molecular wires that connect a metal nanoscale junction in a highly efficient and tunable way. To this aim, we use an STM break-junction approach to control the formation of a nanometric gap between two Au electrodes, both functionalized with mercaptopyridinium (bottom) and mercaptopyridine (top). When metallophthalocyanine is introduced into the functionalized metal nanojunction, stable molecular connections between the two electrodes are formed through axial coordination to the top and bottom pyridine moieties. We show that the highest conductance of the resulting nanoscale molecular wire corresponds to an Fe-phthalocyanine as compare to a Cu-phthalocyanine, which follows the electrocatalytic trend for such molecular systems. These results not only demonstrate a new strategy to design new families of highly conductive and tunable nanoscale molecular wires, but it also brings a new nanoscale electrical platform to help understanding some fundamental mechanistic aspects of molecular electrocatalysis.
JTD Keywords: Single-molecule wires, Metallophthalocyanine, Electrocatalytic molecular platform, Molecular Electronics, STM break-junction
Fonollosa, J., Sheik, S., Huerta, R., Marco, S., (2015). Reservoir computing compensates slow response of chemosensor arrays exposed to fast varying gas concentrations in continuous monitoring Sensors and Actuators B: Chemical 215, 618-629
Metal oxide (MOX) gas sensors arrays are a predominant technological choice to perform fundamental tasks of chemical detection. Yet, their use has been mainly limited to relatively controlled instrument configurations where the sensor array is placed within a closed measurement chamber. Usually, the experimental protocol is defined beforehand and it includes three stages: the array is first exposed to a gas reference, then to the gas sample, and finally to the reference again to recover the initial state. Such sampling procedure requires signal acquisition during the complete experimental protocol and usually delays the output prediction until the predefined measurement duration is complete. Due to the slow time response of chemical sensors, the completion of the measurement typically requires minutes. In this paper we propose the use of reservoir computing (RC) algorithms to overcome the slow temporal dynamics of chemical sensor arrays, allowing identification and quantification of chemicals of interest continuously and reducing measurement delays. We generated two datasets to test the ability of RC algorithms to provide accurate and continuous prediction to fast varying gas concentrations in real time. Both datasets - one generated with synthetic data and the other acquired from actual gas sensors - provide time series of MOX sensors exposed to binary gas mixtures where concentration levels change randomly over time. Our results show that our approach improves the time response of the sensory system and provides accurate predictions in real time, making the system specifically suitable for online monitoring applications. Finally, the collected dataset and developed code are made publicly available to the research community for further studies.
JTD Keywords: Chemical sensors, Continuous gas prediction, Electronic nose, Real-time detection, Reservoir computing
Hoyo, J., Guaus, E., Torrent-Burgués, J., Sanz, F., (2015). Biomimetic monolayer films of digalactosyldiacylglycerol incorporating plastoquinone
Biochimica et Biophysica Acta - Biomembranes , 1848, (6), 1341-1351
The photosynthesis is the process used by plants and bacteria cells to convert inorganic matter in organic thanks to the light energy. This process consist on several steps, being one of them the electronic transport from the photosystem II to the cytochrome thanks to plastoquinone-9 (PQ). Here we prepare membranes that mimic the characteristics and composition of natural photosynthetic cell membranes and we characterize them in order to obtain the PQ molecules position in the membrane and their electrochemical behaviour. The selected galactolipid is digalactosyldiacylglycerol (DGDG) that represents the 30% of the thylakoid membrane lipid content. The results obtained are worthful for several science fields due to the relevance of galactolipids as anti-algal, anti-viral, anti-tumor and anti-inflammatory agents and the antioxidant and free radical scavenger properties of prenylquinones. Both pure components (DGDG and PQ) and the DGDG:PQ mixtures have been studied using surface pressure-area isotherms. These isotherms give information about the film stability and indicate the thermodynamic behaviour of the mixture and their physical state. The Langmuir-Blodgett (LB) film has been transferred forming a monolayer that mimics the bottom layer of the biological membranes. This monolayer on mica has been topographically characterized using AFM and both the height and the physical state that they present have been obtained. Moreover, these monolayers have been transferred onto ITO that is a hydrophilic substrate with good optical and electrical features, so that, it is suitable for studying the electrochemical behaviour of these systems and it is a good candidate for energy producing devices.
JTD Keywords: Biomimetic membrane, Digalactosyldiacylglycerol, Electron transfer, LangmuirBlodgett film, Modified ITO electrode, Plastoquinone
Hoyo, J., Guaus, E., Torrent-Burgués, J., Sanz, F., (2015). Electrochemistry of LB films of mixed MGDG: UQ on ITO
Bioelectrochemistry , 104, 26-34
The electrochemical behaviour of biomimetic monolayers of monogalactosyldiacylglycerol (MGDG) incorporating ubiquinone-10 (UQ) has been investigated. MGDG is the principal component in the thylakoid membrane and UQ seems a good substitute for plastoquinone-9, involved in photosynthesis chain. The monolayers have been performed using the Langmuir and Langmuir-Blodgett (LB) techniques and the redox behaviour of the LB films, transferred at several surface pressures on a glass covered with indium-tin oxide (ITO), has been characterized by cyclic voltammetry. The cyclic voltammograms show that UQ molecules present two redox processes (I and II) at high UQ content and high surface pressures, and only one redox process (I) at low UQ content and low surface pressures. The apparent rate constants calculated for processes I and II indicate a different kinetic control for the reduction and the oxidation of UQ/UQH2 redox couple, being kRapp(I)=2.2·10-5s-1, kRapp(II)=5.1·10-14 kOapp(I)=3.3·10-3s-1 and kOapp(II)=6.1·10-6s-1, respectively. The correlation of the redox response with the physical states of the LB films allows determining the positions of the UQ molecules in the biomimetic monolayer, which change with the surface pressure and the UQ content. These positions are known as diving and swimming.
JTD Keywords: Cyclic voltammetry, Electron transfer, Langmuir-Blodgett film, Modified ITO electrode, Monogalactosyldiacylglycerol, Ubiquinone
Fernández-Remolar, D. C., Santamaría, J., Amils, R., Parro, V., Gómez-Ortíz, D., Izawa, M. R. M., Banerjee, N. R., Pérez-Rodríguez', R., Rodríguez, N., López-Martínez, N., (2015). Formation of iron-rich shelled structures by microbial communities
Journal of Geophysical Research: Biogeosciences , 120, (1), 147-168
In this paper, we describe the discovery and characterization of shelled structures that occur inside galleries of Pyrenees mines. The structures are formed by the mineralization of iron and zinc oxides, dominantly franklinite (ZnFe2O4) and poorly ordered goethite (α-FeO(OH)). Subsurface oxidation and hydration of polymetallic sulfide orebodies produce solutions rich in dissolved metal cations including Fe2+/3+ and Zn2+. The microbially precipitated shell-like structure grows by lateral or vertical stacking of thin laminae of iron oxide particles which are accreted mostly by fungal filaments. The resulting structures are composed of randomly oriented aggregates of needle-like, uniform-sized crystals, suggesting some biological control in the structure formation. Such structures are formed by the integration of two separated shells, following a complex process driven likely by different strategies of fungal microorganisms that produced the complex macrostructure.
JTD Keywords: Geobiology, Iron oxides, Microbial mineralization
Seo, K. D., Kwak, B. K., Sánchez, S., Kim, D. S., (2015). Microfluidic-assisted fabrication of flexible and location traceable organo-motor
IEEE Transactions on Nanobioscience , 14, (3), 298-304
In this paper, we fabricate a flexible and location traceable micromotor, called organo-motor, assisted by microfluidic devices and with high throughput. The organo-motors are composed of organic hydrogel material, poly (ethylene glycol) diacrylate (PEGDA), which can provide the flexibility of their structure. For spatial and temporal traceability of the organo-motors under magnetic resonance imaging (MRI), superparamagnetic iron oxide nanoparticles (SPION; Fe3O4) were incorporated into the PEGDA microhydrogels. Furthermore, a thin layer of platinum (Pt) was deposited onto one side of the SPION-PEGDA microhydrogels providing geometrical asymmetry and catalytic propulsion in aqueous fluids containing hydrogen peroxide solution, H2O2. Furthermore, the motion of the organo-motor was controlled by a small external magnet enabled by the presence of SPION in the motor architecture.
JTD Keywords: Flexible, Hydrogel, Magnetic resonance imaging, Microfluidics, Micromotor, Microparticle, Organo-motor, Poly (ethylene glycol) diacrylate, Self-propulsion, Superparamagnetic iron oxide nanoparticles
Garde, A., Giraldo, B. F., Jané, R., Latshang, T. D., Turk, A. J., Hess, T., Bosch, M-.M., Barthelmes, D., Merz, T. M., Hefti, J. Pichler, Schoch, O. D., Bloch, K. E., (2015). Time-varying signal analysis to detect high-altitude periodic breathing in climbers ascending to extreme altitude
Medical & Biological Engineering & Computing , 53, (8), 699-712
This work investigates the performance of cardiorespiratory analysis detecting periodic breathing (PB) in chest wall recordings in mountaineers climbing to extreme altitude. The breathing patterns of 34 mountaineers were monitored unobtrusively by inductance plethysmography, ECG and pulse oximetry using a portable recorder during climbs at altitudes between 4497 and 7546 m on Mt. Muztagh Ata. The minute ventilation (VE) and heart rate (HR) signals were studied, to identify visually scored PB, applying time-varying spectral, coherence and entropy analysis. In 411 climbing periods, 30–120 min in duration, high values of mean power (MPVE) and slope (MSlopeVE) of the modulation frequency band of VE, accurately identified PB, with an area under the ROC curve of 88 and 89 %, respectively. Prolonged stay at altitude was associated with an increase in PB. During PB episodes, higher peak power of ventilatory (MPVE) and cardiac (MP LF HR ) oscillations and cardiorespiratory coherence (MP LF Coher ), but reduced ventilation entropy (SampEnVE), was observed. Therefore, the characterization of cardiorespiratory dynamics by the analysis of VE and HR signals accurately identifies PB and effects of altitude acclimatization, providing promising tools for investigating physiologic effects of environmental exposures and diseases.
JTD Keywords: High-altitude periodic breathing, Cardiorespiratory characterization, Time-varying spectral analysis, Acclimatization, Hypoxia
da Palma, R. K., Farré, R., Montserrat, J. M., Gorbenko Del Blanco, D., Egea, G., de Oliveira, L. V. F., Navajas, D., Almendros, I., (2015). Increased upper airway collapsibility in a mouse model of Marfan syndrome
Respiratory Physiology & Neurobiology , 207, 58-60
Marfan syndrome (MFS) is a genetic disorder caused by mutations in the FBN1 gene that codifies for fibrilin-1. MFS affects elastic fiber formation and the resulting connective tissue shows abnormal tissue laxity and organization. Although an increased prevalence of obstructive sleep apnea among patients with MFS has been described, the potential effects of this genetic disease on the collapsible properties of the upper airway are unknown. The aim of this study was to assess the collapsible properties of the upper airway in a mouse model of MFS Fbn1(C1039G/+) that is representative of most of the clinical manifestations observed in human patients. The upper airway in wild-type and Marfan mice was cannulated and its critical pressure (Pcrit) was measured in vivo by increasing the negative pressure through a controlled pressure source. Pcrit values from MFS mice were higher (less negative) compared to wild-type mice (-3.1±0.9cmH2O vs. -7.8±2.0cm H2O) suggesting that MFS increases the upper airway collapsibility, which could in turn explain the higher prevalence of OSA in MFS patients.
JTD Keywords: Marfan syndrome, Obstructive sleep apnea, Upper airway collapsibility
Urra, O., Casals, A., Jané, R., (2015). The impact of visual feedback on the motor control of the upper-limb Engineering in Medicine and Biology Society (EMBC)
37th Annual International Conference of the IEEE , IEEE (Milan, Italy) , 3945-3948
Stroke is a leading cause of adult disability with upper-limb hemiparesis being one of the most frequent consequences. Given that stroke only affects the paretic arm's control structure (the set of synergies and activation vectors needed to perform a movement), we propose that the control structure of the non-affected arm can serve as a physiological reference to rehabilitate the paretic arm. However, it is unclear how rehabilitation can effectively tune the control structure of a patient. The use of Visual Feedback (VF) is recommended to boost stroke rehabilitation, as it is able to positively modify neural mechanisms and improve motor performance. Thus, in this study we investigate whether VF can effectively modify the control structure of the upper-limb. We asked six neurologically intact subjects to perform a complete upper-limb rehabilitation routine comprised of 12 movements in absence and presence of VF. Our results indicate that VF significantly increases interlimb similarity both in terms of synergies and activation coefficients. However, the magnitude of improvement depended upon each subject. In general, VF brings the control structure of the nondominant side closer to the control structure of dominant side, suggesting that VF modifies the control structure towards more optimized motor patterns. This is especially interesting because stroke mainly affects the activation coefficients of patients and because it has been shown that the control of the affected side resembles that of the nondominant side. In conclusion, VF may enhance motor performance by effectively tuning the control-structure. Notably, this finding offers new insights to design improved stroke rehabilitation.
JTD Keywords: Bars, Biomedical engineering, Electrodes, Electromyography, Mirrors, Muscles, Visualization
Estrada, L., Torres, A., Sarlabous, L., Jané, R., (2015). Respiratory signal derived from the smartphone built-in accelerometer during a Respiratory Load Protocol Engineering in Medicine and Biology Society (EMBC)
37th Annual International Conference of the IEEE , IEEE (Milan, Italy) , 6768-6771
The scope of our work focuses on investigating the potential use of the built-in accelerometer of the smartphones for the recording of the respiratory activity and deriving the respiratory rate. Five healthy subjects performed an inspiratory load protocol. The excursion of the right chest was recorded using the built-in triaxial accelerometer of a smartphone along the x, y and z axes and with an external uniaxial accelerometer. Simultaneously, the respiratory airflow and the inspiratory mouth pressure were recorded, as reference respiratory signals. The chest acceleration signal recorded in the z axis with the smartphone was denoised using a scheme based on the ensemble empirical mode decomposition, a noise data assisted method which decomposes nonstationary and nonlinear signals into intrinsic mode functions. To distinguish noisy oscillatory modes from the relevant modes we use the detrended fluctuation analysis. We reported a very strong correlation between the acceleration of the z axis of the smartphone and the reference accelerometer across the inspiratory load protocol (from 0.80 to 0.97). Furthermore, the evaluation of the respiratory rate showed a very strong correlation (0.98). A good agreement was observed between the respiratory rate estimated with the chest acceleration signal from the z axis of the smartphone and with the respiratory airflow signal: Bland-Altman limits of agreement between -1.44 and 1.46 breaths per minute with a mean bias of -0.01 breaths per minute. This preliminary study provides a valuable insight into the use of the smartphone and its built-in accelerometer for respiratory monitoring.
JTD Keywords: Acceleration, Accelerometers, Correlation, Empirical mode decomposition, Fluctuations, Protocols, Time series analysis
Palleja, T., Balsa, R., Tresanchez, M., Moreno, J., Teixido, M., Font, D., Marco, S., Pomareda, V., Palacin, J., (2014). Corridor gas-leak localization using a mobile Robot with a photo ionization detector sensor
Sensor Letters , 12, (6-7), 974-977
The use of an autonomous mobile robot to locate gas-leaks and air quality monitoring in indoor environments are promising tasks that will avoid risky human operations. However, these are challenging tasks due to the chaotic gas profile propagation originated by uncontrolled air flows. This paper proposes the localization of an acetone gas-leak in a 44 m-length indoor corridor with a mobile robot equipped with a PID sensor. This paper assesses the influence of the mobile robot velocity and the relative height of the PID sensor in the profile of the measurements. The results show weak influence of the robot velocity and strong influence of the relative height of the PID sensor. An estimate of the gas-leak location is also performed by computing the center of mass of the highest gas concentrations.
JTD Keywords: Gas source detection, LIDAR sensor, Mobile robot, PID sensor, SLAM, Acetone, Air quality, Gases, Indoor air pollution, Mobile robots, Robots, Air quality monitoring, Autonomous Mobile Robot, Gas sources, Indoor environment, Leak localization, LIDAR sensors, Profile propagation, SLAM, Ionization of gases
Darwish, Nadim., Aragonès, A. C., Darwish, T., Ciampi, S., Díez-Pérez, I., (2014). Multi-responsive photo- and chemo-electrical single-molecule switches Nano Letters 14, (12), 7064-7070
Incorporating molecular switches as the active components in nanoscale electrical devices represents a current challenge in molecular electronics. It demands key requirements that need to be simultaneously addressed including fast responses to external stimuli and stable attachment of the molecules to the electrodes while mimicking the operation of conventional electronic components. Here, we report a single-molecule switching device that responds electrically to optical and chemical stimuli. A light pointer or a chemical signal can rapidly and reversibly induce the isomerization of bifunctional spiropyran derivatives in the bulk reservoir and, consequently, switch the electrical conductivity of the single-molecule device between a low and a high level. The spiropyran derivatives employed are chemically functionalized such that they can respond in fast but practical time scales. The unique multistimuli response and the synthetic versatility to control the switching schemes of this single-molecule device suggest spiropyran derivatives as key candidates for molecular circuitry.
JTD Keywords: Molecular Electronics, Multi-Responsive Molecular Switches, Photo- and Chemo-Switches Spiropyran, Single-Molecule Conductance, STM Break-Junction, Electronic equipment, Isomerization, Molecular electronics, Photochromism, Electrical conductivity, Electronic component, Molecular switches, Single-molecule conductances, Single-molecule devices, Spiropyran derivatives, Spiropyrans, STM Break-Junction, Molecules
Cuervo, A., Dans, P. D., Carrascosa, J. L., Orozco, M., Gomila, G., Fumagalli, L., (2014). Direct measurement of the dielectric polarization properties of DNA Proceedings of the National Academy of Sciences of the United States of America 111, (35), E3624-E3630
The electric polarizability of DNA, represented by the dielectric constant, is a key intrinsic property that modulates DNA interaction with effector proteins. Surprisingly, it has so far remained unknown owing to the lack of experimental tools able to access it. Here, we experimentally resolved it by detecting the ultraweak polarization forces of DNA inside single T7 bacteriophages particles using electrostatic force microscopy. In contrast to the common assumption of low-polarizable behavior like proteins (εr ~ 2–4), we found that the DNA dielectric constant is ~ 8, considerably higher than the value of ~ 3 found for capsid proteins. State-of-the-art molecular dynamic simulations confirm the experimental findings, which result in sensibly decreased DNA interaction free energy than normally predicted by Poisson–Boltzmann methods. Our findings reveal a property at the basis of DNA structure and functions that is needed for realistic theoretical descriptions, and illustrate the synergetic power of scanning probe microscopy and theoretical computation techniques.
JTD Keywords: Atomic force microscopy, Atomistic simulations, DNA packaging, DNA-ligand binding, Poisson-Boltzmann equation, capsid protein, DNA, double stranded DNA, amino acid composition, article, atomic force microscopy, bacteriophage, bacteriophage T7, dielectric constant, dipole, DNA binding, DNA packaging, DNA structure, electron microscopy, ligand binding, nonhuman, polarization, priority journal, protein analysis, protein DNA interaction, scanning probe microscopy, static electricity, virion, virus capsid, virus particle, atomic force microscopy, atomistic simulations, DNA packaging, DNA-ligand binding, Poisson-Boltzmann equation, Bacteriophage T7, Capsid, Cations, Dielectric Spectroscopy, DNA, DNA, Viral, DNA-Binding Proteins, Electrochemical Techniques, Ligands, Microscopy, Atomic Force, Models, Chemical, Nuclear Proteins
Dols-Perez, A., Fumagalli, L., Gomila, G., (2014). Structural and nanomechanical effects of cholesterol in binary and ternary spin-coated single lipid bilayers in dry conditions Colloids and Surfaces B: Biointerfaces 116, 295-302
We investigate the effects of Cholesterol (Chol) in the structural and nanomechanical properties of binary and ternary spin-coated single lipid bilayers made of Dioleoylphosphatidylcholine (DOPC) and Sphingomyelin (SM) in dry conditions. We show that for the DOPC/Chol bilayers, Chol induces an initial increase of the bilayer thickness, followed by decrease for concentrations above 30% Chol. The mechanical properties, instead, appear practically insensitive to the Chol content. For the SM/Chol bilayers we have observed both the thinning of the bilayer and the decrease of the force necessary to break it for Chol content above 40. mol%. In both binary mixtures phase separation is not observed. For ternary single bilayers of DOPC/SM/Chol, Chol induces phase segregation and the formation of domains resembling lipid rafts. The domains show a thickness and mechanical response clearly distinct from the surrounding phase and dependent on the relative Chol content. Based on the results obtained for the binary mixtures, DOPC- and SM-enriched domains can be identified. We highlight that many of the effects of Chol reported here for the dry multicomponent single lipid bilayers resemble closely those observed in hydrated bilayers, thus offering an additional insight into their properties.
JTD Keywords: AFM, Air-stable lipid layer, Force spectroscopy, Lipid raft, Spin-coating
Melo, E., Cárdenes, N., Garreta, E., Luque, T., Rojas, M., Navajas, D., Farré, R., (2014). Inhomogeneity of local stiffness in the extracellular matrix scaffold of fibrotic mouse lungs
Journal of the Mechanical Behavior of Biomedical Materials , 37, 186-195
Lung disease models are useful to study how cell engraftment, proliferation and differentiation are modulated in lung bioengineering. The aim of this work was to characterize the local stiffness of decellularized lungs in aged and fibrotic mice. Mice (2- and 24-month old; 14 of each) with lung fibrosis (N=20) and healthy controls (N=8) were euthanized after 11 days of intratracheal bleomycin (fibrosis) or saline (controls) infusion. The lungs were excised, decellularized by a conventional detergent-based (sodium-dodecyl sulfate) procedure and slices of the acellular lungs were prepared to measure the local stiffness by means of atomic force microscopy. The local stiffness of the different sites in acellular fibrotic lungs was very inhomogeneous within the lung and increased according to the degree of the structural fibrotic lesion. Local stiffness of the acellular lungs did not show statistically significant differences caused by age. The group of mice most affected by fibrosis exhibited local stiffness that were ~2-fold higher than in the control mice: from 27.2±1.64 to 64.8±7.1. kPa in the alveolar septa, from 56.6±4.6 to 99.9±11.7. kPa in the visceral pleura, from 41.1±8.0 to 105.2±13.6. kPa in the tunica adventitia, and from 79.3±7.2 to 146.6±28.8. kPa in the tunica intima. Since acellular lungs from mice with bleomycin-induced fibrosis present considerable micromechanical inhomogeneity, this model can be a useful tool to better investigate how different degrees of extracellular matrix lesion modulate cell fate in the process of organ bioengineering from decellularized lungs.
JTD Keywords: Ageing, Atomic force microscopy, Decellularization, Lung fibrosis, Tissue engineering, Atomic force microscopy, Biological organs, Peptides, Sodium dodecyl sulfate, Sodium sulfate, Tissue engineering, Ageing, Decellularization, Extracellular matrices, Healthy controls, Inhomogeneities, Lung fibrosis, Micro-mechanical, Statistically significant difference, Mammals, bleomycin, adventitia, animal experiment, animal model, article, atomic force microscopy, bleomycin-induced pulmonary fibrosis, cell fate, controlled study, extracellular matrix, female, intima, lung alveolus, lung fibrosis, lung mechanics, mechanical probe, microenvironment, mouse, nonhuman, pleura, priority journal, rigidity, tissue engineering
Uriarte, J. J., Nonaka, P. N., Campillo, N., Palma, R. K., Melo, E., de Oliveira, L. V. F., Navajas, D., Farré, R., (2014). Mechanical properties of acellular mouse lungs after sterilization by gamma irradiation
Journal of the Mechanical Behavior of Biomedical Materials , 40, 168-177
Lung bioengineering using decellularized organ scaffolds is a potential alternative for lung transplantation. Clinical application will require donor scaffold sterilization. As gamma-irradiation is a conventional method for sterilizing tissue preparations for clinical application, the aim of this study was to evaluate the effects of lung scaffold sterilization by gamma irradiation on the mechanical properties of the acellular lung when subjected to the artificial ventilation maneuvers typical within bioreactors. Twenty-six mouse lungs were decellularized by a sodium dodecyl sulfate detergent protocol. Eight lungs were used as controls and 18 of them were submitted to a 31kGy gamma irradiation sterilization process (9 kept frozen in dry ice and 9 at room temperature). Mechanical properties of acellular lungs were measured before and after irradiation. Lung resistance (RL) and elastance (EL) were computed by linear regression fitting of recorded signals during mechanical ventilation (tracheal pressure, flow and volume). Static (Est) and dynamic (Edyn) elastances were obtained by the end-inspiratory occlusion method. After irradiation lungs presented higher values of resistance and elastance than before irradiation: RL increased by 41.1% (room temperature irradiation) and 32.8% (frozen irradiation) and EL increased by 41.8% (room temperature irradiation) and 31.8% (frozen irradiation). Similar increases were induced by irradiation in Est and Edyn. Scanning electron microscopy showed slight structural changes after irradiation, particularly those kept frozen. Sterilization by gamma irradiation at a conventional dose to ensure sterilization modifies acellular lung mechanics, with potential implications for lung bioengineering.
JTD Keywords: Gamma irradiation, Lung bioengineering, Lung decellularization, Organ scaffold, Pulmonary mechanics, Decellularization, Gamma irradiation, Mouse lung, Pulmonary mechanics, dodecyl sulfate sodium, animal tissue, Article, artificial ventilation, bioengineering, bioreactor, compliance (physical), controlled study, freezing, gamma irradiation, lung, lung mechanics, lung resistance, male, mouse, nonhuman, room temperature, scanning electron microscopy, tissue scaffold, trachea pressure
Bennetts, Victor, Schaffernicht, Erik, Pomareda, Victor, Lilienthal, Achim, Marco, Santiago, Trincavelli, Marco, (2014). Combining non selective gas sensors on a mobile robot for identification and mapping of multiple chemical compounds Sensors 14, (9), 17331-17352
In this paper, we address the task of gas distribution modeling in scenarios where multiple heterogeneous compounds are present. Gas distribution modeling is particularly useful in emission monitoring applications where spatial representations of the gaseous patches can be used to identify emission hot spots. In realistic environments, the presence of multiple chemicals is expected and therefore, gas discrimination has to be incorporated in the modeling process. The approach presented in this work addresses the task of gas distribution modeling by combining different non selective gas sensors. Gas discrimination is addressed with an open sampling system, composed by an array of metal oxide sensors and a probabilistic algorithm tailored to uncontrolled environments. For each of the identified compounds, the mapping algorithm generates a calibrated gas distribution model using the classification uncertainty and the concentration readings acquired with a photo ionization detector. The meta parameters of the proposed modeling algorithm are automatically learned from the data. The approach was validated with a gas sensitive robot patrolling outdoor and indoor scenarios, where two different chemicals were released simultaneously. The experimental results show that the generated multi compound maps can be used to accurately predict the location of emitting gas sources.
JTD Keywords: Environmental monitoring, Gas discrimination, Gas distribution mapping, Service robots, Open sampling systems, PID, Metal oxide sensors
Nonaka, P. N., Uriarte, J. J., Campillo, N., Melo, E., Navajas, D., Farré, R., Oliveira, L. V. F., (2014). Mechanical properties of mouse lungs along organ decellularization by sodium dodecyl sulfate
Respiratory Physiology & Neurobiology , 200, 1-5
Lung decellularization is based on the use of physical, chemical, or enzymatic methods to break down the integrity of the cells followed by a treatment to extract the cellular material from the lung scaffold. The aim of this study was to characterize the mechanical changes throughout the different steps of lung decellularization process. Four lungs from mice (C57BL/6) were decellularized by using a conventional protocol based on sodium dodecyl sulfate. Lungs resistance (RL) and elastance (EL) were measured along decellularization steps and were computed by linear regression fitting of tracheal pressure, flow, and volume during mechanical ventilation. Transients differences found were more distinct in an intermediate step after the lungs were rinsed with deionized water and treated with 1% SDS, whereupon the percentage of variation reached approximately 80% for resistance values and 30% for elastance values. In conclusion, although a variation in extracellular matrix stiffness was observed during the decellularization process, this variation can be considered negligible overall because the resistance and elastance returned to basal values at the final decellularization step.
JTD Keywords: Lung bioengineering, Lung decellularization, Organ scaffold, dodecyl sulfate sodium, animal tissue, article, artificial ventilation, compliance (physical), controlled study, enzyme chemistry, extracellular matrix, female, flow, lung, lung decellularization, lung pressure, lung resistance, mouse, nonhuman, positive end expiratory pressure, priority journal, rigidity, tissue engineering, trachea pressure
Torrent-Burgués, J., Cea, P., Giner, I., Guaus, E., (2014). Characterization of Langmuir and Langmuir-Blodgett films of an octasubstituted zinc phthalocyanine
Thin Solid Films , 556, 485-494
In this work we report the fabrication of Langmuir and Langmuir-Blodgett (LB) films of a substituted ZnPc (octakis(oxyoctyl)phthalocyanine of zinc), and their characterization by means of several techniques. These characterization techniques include surface pressure (π-A) and surface potential (ΔV-A) isotherms as well as UV-vis Reflection spectroscopy and Brewster Angle Microscopy (BAM) for the films at the air-water interface together with UV-vis absorption and IR spectroscopies and Atomic Force Microscopy (AFM) for the LB films. The π-A and ΔV-A isotherms and BAM images indicate a phase transition at a surface pressure of ca. 9 mN/m and a multilayer formation at surface pressures around 19-20 mN/m; at a surface pressure around 27 mN/m a disordered collapse of the film occurs. In addition, AFM images of LB films at π = 10 mN/m and π = 20 mN/m show a monomolecular and a multilayered film, respectively. The comparison of the UV-vis spectrum of ZnPc in solution, the reflection spectra of the Langmuir films and UV-vis spectra of LB films reveals a significant reduction in the Q band intensity for the films, indicative of an organization of ZnPc in the Langmuir and LB films versus the random distribution in solution. The UV-vis Reflection spectra are also consistent with multilayer formation at surface pressures around 19-20 mN/m. The relative intensities of the IR spectrum bands change from the KBr pellet to the LB film which is also attributable to orientation effects in the film. Cyclic voltammetric experiments of LB films incorporating the ZnPc derivative show peaks that can be correlated with redox processes occurring in the phthalocyanine ring. A small but significant influence of the surface pressure and the number of deposited layers in the electrochemical behaviour is observed. The electrochemical response of cast films exhibits some differences with respect to that of LB films which have been attributed to their different molecular organizations.
JTD Keywords: Atomic Force Microscopy, Electrochemistry, Langmuir-Blodgett, Multilayers, Optical spectroscopy techniques, Zinc phthalocyanine, Atomic force microscopy, Electrochemistry, Interfaces (materials), Isotherms, Multilayers, Nitrogen compounds, Optical multilayers, Organic polymers, Zinc compounds, Brewster angle microscopy, Characterization techniques, Electrochemical behaviour, Langmuir and langmuir-blodgett films, Langmuir-blodgett, Optical spectroscopy techniques, UV-Vis Reflection Spectroscopy, Zinc phthalocyanines, Langmuir Blodgett films
Sheik, S., Marco, S., Huerta, R., Fonollosa, J., (2014). Continuous prediction in chemoresisitive gas sensors using reservoir computing Procedia Engineering
28th European Conference on Solid-State Transducers (EUROSENSORS 2014) , Eurosensors (Brescia, Italy) 87, 843-846
Although Metal Oxide (MOX) sensors are predominant choices to perform fundamental tasks of chemical detection, their use has been mainly limited to relatively controlled scenarios where a gas sensor array is first exposed to a reference, then to the gas sample, and finally to the reference again to recover the initial state. In this paper we propose the use of MOX sensors along with Reservoir Computing algorithms to identify chemicals of interest. Our approach allows continuous gas monitoring in simple experimental setups without the requirement of acquiring recovery transient of the sensors, thereby making the system specifically suitable for online monitoring applications.
JTD Keywords: Chemical sensing, Reservoir computing, Gas sensors, Dynamic gas mixtures, Electronic nose
Correa, L.S., Giraldo, B., Correa, R., Arini, P.D., Laciar, E., (2014). Estudio de la pausa espiratoria en pacientes con enfermedades obstructivas en proceso de desconexión de la ventilación mecánica IFMBE Proceedings
VI Latin American Congress on Biomedical Engineering (CLAIB 2014) , Springer (Paraná, Argentina) 49, 705-708
In this work, the flow signal Expiratory Pause (EP) temporal analysis is used in 18 patients with obstructive lung diseases going through spontaneous breathing trial at weaning process. The main objective was to identify the patients who were successfully disconnected (success group: 9 patients), and those who were not (failure and reintubated group: 9 patients). A variable selection stage was done by mean group comparison and step wise variable inclusion, leading to a 3 parameters set: EP time median; cycle time mean; and median absolute deviation of the EP maxima local number. Next, this set was used in a classifier based on linear discriminant analysis, which results in 17 patients (94.4%) correctly classified, with 88.9% of specificity (Sp) and 100% of sensitivity (Se). Finally, applying the leave-one-out cross validation method, results were 88.9% of correctly classified patients (Sp=77.8% and Se=100%). In conclusion, the proposed parameters showed a good performance and could be used to help therapists to wean patients with obstructive diseases.
JTD Keywords: Chronic Obstructive Pulmonary Disease (COPD), Weaning, Mechanical ventilation, Expiratory pause
Estrada, L., Torres, A., Sarlabous, L., Fiz, J. A., Jané, R., (2014). Respiratory rate detection by empirical mode decomposition method applied to diaphragm mechanomyographic signals Engineering in Medicine and Biology Society (EMBC)
36th Annual International Conference of the IEEE , IEEE (Chicago, USA) , 3204-3207
Non-invasive evaluation of respiratory activity is an area of increasing research interest, resulting in the appearance of new monitoring techniques, ones of these being based on the analysis of the diaphragm mechanomyographic (MMGdi) signal. The MMGdi signal can be decomposed into two parts: (1) a high frequency activity corresponding to lateral vibration of respiratory muscles, and (2) a low frequency activity related to excursion of the thoracic cage. The purpose of this study was to apply the empirical mode decomposition (EMD) method to obtain the low frequency of MMGdi signal and selecting the intrinsic mode functions related to the respiratory movement. With this intention, MMGdi signals were acquired from a healthy subject, during an incremental load respiratory test, by means of two capacitive accelerometers located at left and right sides of rib cage. Subsequently, both signals were combined to obtain a new signal which contains the contribution of both sides of thoracic cage. Respiratory rate (RR) measured from the mechanical activity (RRMmg) was compared with that measured from inspiratory pressure signal (RRP). Results showed a Pearson's correlation coefficient (r = 0.87) and a good agreement (mean bias = -0.21 with lower and upper limits of -2.33 and 1.89 breaths per minute, respectively) between RRmmg and RRP measurements. In conclusion, this study suggests that RR can be estimated using EMD for extracting respiratory movement from low mechanical activity, during an inspiratory test protocol.
JTD Keywords: Accelerometers, Band-pass filters, Biomedical measurement, Empirical mode decomposition, Estimation, IP networks, Muscles
Lozano-Garcia, M., Fiz, J. A., Jané, R., (2014). Analysis of normal and continuous adventitious sounds for the assessment of asthma IFMBE Proceedings
XIII Mediterranean Conference on Medical and Biological Engineering and Computing 2013 (ed. Roa Romero, Laura M.), Springer International Publishing (London, UK) 41, 981-984
Assessment of asthma is a difficult procedure which is based on the correlation of multiple factors. A major component in the diagnosis of asthma is the assessment of BD response, which is performed by traditional spirometry. In this context, the analysis of respiratory sounds (RS) provides relevant and complementary information about the function of the respiratory system. In particular, continuous adventitious sounds (CAS), such as wheezes, contribute to assess the severity of patients with obstructive diseases. On the other hand, the intensity of normal RS is dependent on airflow level and, therefore, it changes depending on the level of obstruction. This study proposes a new approach to RS analysis for the assessment of asthmatic patients, by combining the quantification of CAS and the analysis of the changes in the normal sound intensity-airflow relationship. According to results obtained from three patients with different characteristics, the proposed technique seems more sensitive and promising for the assessment of asthma.
JTD Keywords: Asthma, Bronchodilator response, Continuous adventitious sound, Respiratory sound intensity, Wheezes
Marbán, Arturo, Casals, Alicia, Fernández, Josep, Amat, Josep, (2014). Haptic feedback in surgical robotics: Still a challenge Advances in Intelligent Systems and Computing
ROBOT2013: First Iberian Robotics Conference (ed. Armada, Manuel A., Sanfeliu, Alberto, Ferre, Manuel), Springer International Publishing 252, 245-253
Endowing current surgical robotic systems with haptic feedback to perform minimally invasive surgery (MIS), such as laparoscopy, is still a challenge. Haptic is a feature lost in surgical teleoperated systems limiting surgeons capabilities and ability. The availability of haptics would provide important advantages to the surgeon: Improved tissue manipulation, reducing the breaking of sutures and increase the feeling of telepresence, among others. To design and develop a haptic system, the measurement of forces can be implemented based on two approaches: Direct and indirect force sensing. MIS performed with surgical robots, imposes many technical constraints to measure forces, such as: Miniaturization, need of sterilization or materials compatibility, making it necessary to rely on indirect force sensing. Based on mathematical models of the components involved in an intervention and indirect force sensing techniques, a global perspective on how to address the problem of measurement of tool-tissue interaction forces is presented.
JTD Keywords: Surgical robotics, Haptic feedback, Indirect force sensing, Machine learning, Data fusion, Mathematical models
Vinagre, M., Aranda, J., Casals, A., (2014). An interactive robotic system for human assistance in domestic environments
Computers Helping People with Special Needs (ed. Miesenberger, K., Fels, D., Archambault, D., Pe, Zagler), Springer International Publishing 8548, 152-155
This work introduces an interactive robotic system for assistance, conceived to tackle some of the challenges that domestic environments impose. The system is organized into a network of heterogeneous components that share both physical and logical functions to perform complex tasks. It consists of several robots for object manipulation, an advanced vision system that supplies in-formation about objects in the scene and human activity, and a spatial augmented reality interface that constitutes a comfortable means for interacting with the system. A first analysis based on users' experiences confirms the importance of having a friendly user interface. The inclusion of context awareness from visual perception enriches this interface allowing the robotic system to become a flexible and proactive assistant.
JTD Keywords: Accessibility, Activity Recognition, Ambient Intelligence, Human-Robot Interaction, Robot Assistance, Augmented reality, Complex networks, Computer vision, User interfaces, Accessibility, Activity recognition, Ambient intelligence, Domestic environments, Heterogeneous component, Interactive robotics, Robot assistance, Spatial augmented realities, Human assistance, Robotics
Izquierdo-Serra, Mercè, Trauner, Dirk, Llobet, Artur, Gorostiza, Pau, (2013). Optical modulation of neurotransmission using calcium photocurrents through the ion channel LiGluR Frontiers in Molecular Neuroscience 6, (Article 3), 1-6
A wide range of light-activated molecules (photoswitches and phototriggers) have been used to the study of computational properties of an isolated neuron by acting pre and postsynaptically. However, new tools are being pursued to elicit a presynaptic calcium influx that triggers the release of neurotransmitters, most of them based in calcium-permeable Channelrhodopsin-2 mutants. Here we describe a method to control exocytosis of synaptic vesicles through the use of a light-gated glutamate receptor (LiGluR), which has recently been demonstrated that supports secretion by means of calcium influx in chromaffin cells. Expression of LiGluR in hippocampal neurons enables reversible control of neurotransmission with light, and allows modulating the firing rate of the postsynaptic neuron with the wavelength of illumination. This method may be useful for the determination of the complex transfer function of individual synapses.
JTD Keywords: Calcium, Neurotransmission, Optogenetics, Neural coding, Firing rate, Optical control, Synaptic transfer function
Sarlabous, L., Torres, A., Fiz, J. A., Morera, J., Jané, R., (2013). Index for estimation of muscle force from mechanomyography based on the Lempel-Ziv algorithm
Journal of Electromyography and Kinesiology , 23, (3), 548-557
The study of the amplitude of respiratory muscle mechanomyographic (MMG) signals could be useful in clinical practice as an alternative non-invasive technique to assess respiratory muscle strength. The MMG signal is stochastic in nature, and its amplitude is usually estimated by means of the average rectified value (ARV) or the root mean square (RMS) of the signal. Both parameters can be used to estimate MMG activity, as they correlate well with muscle force. These estimations are, however, greatly affected by the presence of structured impulsive noise that overlaps in frequency with the MMG signal. In this paper, we present a method for assessing muscle activity based on the Lempel-Ziv algorithm: the Multistate Lempel-Ziv (MLZ) index. The behaviour of the MLZ index was tested with synthesised signals, with various amplitude distributions and degrees of complexity, and with recorded diaphragm MMG signals. We found that this index, like the ARV and RMS parameters, is positively correlated with changes in amplitude of the diaphragm MMG components, but is less affected by components that have non-random behaviour (like structured impulsive noise). Therefore, the MLZ index could provide more information to assess the MMG-force relationship.
JTD Keywords: Diaphragm, Electromyography, Lempel-Ziv, Mechanomyography, Muscle force, Respiratory muscles
Garde, Ainara, Voss, Andreas, Caminal, Pere, Benito, Salvador, Giraldo, Beatriz F., (2013). SVM-based feature selection to optimize sensitivity-specificity balance applied to weaning
Computers in Biology and Medicine , 43, (5), 533-540
Classification algorithms with unbalanced datasets tend to produce high predictive accuracy over the majority class, but poor predictive accuracy over the minority class. This problem is very common in biomedical data mining. This paper introduces a Support Vector Machine (SVM)-based optimized feature selection method, to select the most relevant features and maintain an accurate and well-balanced sensitivity–specificity result between unbalanced groups. A new metric called the balance index (B) is defined to implement this optimization. The balance index measures the difference between the misclassified data within each class. The proposed optimized feature selection is applied to the classification of patients' weaning trials from mechanical ventilation: patients with successful trials who were able to maintain spontaneous breathing after 48 h and patients who failed to maintain spontaneous breathing and were reconnected to mechanical ventilation after 30 min. Patients are characterized through cardiac and respiratory signals, applying joint symbolic dynamic (JSD) analysis to cardiac interbeat and breath durations. First, the most suitable parameters (C+,C−,σ) are selected to define the appropriate SVM. Then, the feature selection process is carried out with this SVM, to maintain B lower than 40%. The best result is obtained using 6 features with an accuracy of 80%, a B of 18.64%, a sensitivity of 74.36% and a specificity of 82.42%.
JTD Keywords: Support vector machines, Balance index, Sensitivity-specificity balance, Cardiorespiratory interaction, Joint symbolic dynamics, Feature selection, Weaning procedure
Giraldo, B. F., Tellez, J. P., Herrera, S., Benito, S., (2013). Analysis of heart rate variability in elderly patients with chronic heart failure during periodic breathing CinC 2013
Computing in Cardiology Conference (CinC) , IEEE (Zaragoza, Spain) , 991-994
Assessment of the dynamic interactions between cardiovascular signals can provide valuable information that improves the understanding of cardiovascular control. Heart rate variability (HRV) analysis is known to provide information about the autonomic heart rate modulation mechanism. Using the HRV signal, we aimed to obtain parameters for classifying patients with and without chronic heart failure (CHF), and with periodic breathing (PB), non-periodic breathing (nPB), and Cheyne-Stokes respiration (CSR) patterns. An electrocardiogram (ECG) and a respiratory flow signal were recorded in 36 elderly patients: 18 patients with CHF and 18 patients without CHF. According to the clinical criteria, the patients were classified into the follow groups: 19 patients with nPB pattern, 7 with PB pattern, 4 with Cheyne-Stokes respiration (CSR), and 6 non-classified patients (problems with respiratory signal). From the HRV signal, parameters in the time and frequency domain were calculated. Frequency domain parameters were the most discriminant in comparisons of patients with and without CHF: PTot (p = 0.02), PLF (p = 0.022) and fpHF (p = 0.021). For the comparison of the nPB vs. CSR patients groups, the best parameters were RMSSD (p = 0.028) and SDSD (p = 0.028). Therefore, the parameters appear to be suitable for enhanced diagnosis of decompensated CHF patients and the possibility of developed periodic breathing and a CSR pattern.
JTD Keywords: cardiovascular system, diseases, electrocardiography, frequency-domain analysis, geriatrics, medical signal processing, patient diagnosis, pneumodynamics, signal classification, Cheyne-Stokes respiration patterns, ECG, autonomic heart rate modulation mechanism, cardiovascular control, cardiovascular signals, chronic heart failure, decompensated CHF patients, dynamic interaction assessment, elderly patients, electrocardiogram, enhanced diagnosis, frequency domain parameters, heart rate variability analysis, patient classification, periodic breathing, respiratory flow signal recording, Electrocardiography, Frequency modulation, Frequency-domain analysis, Heart rate variability, Senior citizens, Standards
Giraldo, B. F., Chaparro, J. A., Caminal, P., Benito, S., (2013). Characterization of the respiratory pattern variability of patients with different pressure support levels Engineering in Medicine and Biology Society (EMBC)
35th Annual International Conference of the IEEE , IEEE (Osaka, Japan) , 3849-3852
One of the most challenging problems in intensive care is still the process of discontinuing mechanical ventilation, called weaning process. Both an unnecessary delay in the discontinuation process and a weaning trial that is undertaken too early are undesirable. In this study, we analyzed respiratory pattern variability using the respiratory volume signal of patients submitted to two different levels of pressure support ventilation (PSV), prior to withdrawal of the mechanical ventilation. In order to characterize the respiratory pattern, we analyzed the following time series: inspiratory time, expiratory time, breath duration, tidal volume, fractional inspiratory time, mean inspiratory flow and rapid shallow breathing. Several autoregressive modeling techniques were considered: autoregressive models (AR), autoregressive moving average models (ARMA), and autoregressive models with exogenous input (ARX). The following classification methods were used: logistic regression (LR), linear discriminant analysis (LDA) and support vector machines (SVM). 20 patients on weaning trials from mechanical ventilation were analyzed. The patients, submitted to two different levels of PSV, were classified as low PSV and high PSV. The variability of the respiratory patterns of these patients were analyzed. The most relevant parameters were extracted using the classifiers methods. The best results were obtained with the interquartile range and the final prediction errors of AR, ARMA and ARX models. An accuracy of 95% (93% sensitivity and 90% specificity) was obtained when the interquartile range of the expiratory time and the breath duration time series were used a LDA model. All classifiers showed a good compromise between sensitivity and specificity.
JTD Keywords: autoregressive moving average processes, feature extraction, medical signal processing, patient care, pneumodynamics, signal classification, support vector machines, time series, ARX, autoregressive modeling techniques, autoregressive models with exogenous input, autoregressive moving average model, breath duration time series, classification method, classifier method, discontinuing mechanical ventilation, expiratory time, feature extraction, final prediction errors, fractional inspiratory time, intensive care, interquartile range, linear discriminant analysis, logistic regression analysis, mean inspiratory flow, patient respiratory volume signal, pressure support level, pressure support ventilation, rapid shallow breathing, respiratory pattern variability characterization, support vector machines, tidal volume, weaning trial, Analytical models, Autoregressive processes, Biological system modeling, Estimation, Support vector machines, Time series analysis, Ventilation
Hernando, D., Alcaine, A., Pueyo, E., Laguna, P., Orini, M., Arcentales, A., Giraldo, B., Voss, A., Bayes-Genis, A., Bailon, R., (2013). Influence of respiration in the very low frequency modulation of QRS slopes and heart rate variability in cardiomyopathy patients CinC 2013
Computing in Cardiology Conference (CinC) , IEEE (Zaragoza, Spain) , 117-120
This work investigates the very low frequency (VLF) modulation of QRS slopes and heart rate variability (HRV). Electrocardiogram (ECG) and respiratory flow signal were acquired from patients with dilated cardiomyopathy and ischemic cardiomyopathy. HRV as well as the upward QRS slope (IUS) and downward QRS slope (IDS) were extracted from the ECG. The relation between HRV and QRS slopes in the VLF band was measured using ordinary coherence in 5-minute segments. Partial coherence was then used to remove the influence that respiration simultaneously exerts on HRV and QRS slopes. A statistical threshold was determined, below which coherence values were considered not to represent a linear relation. 7 out of 276 segments belonging to 5 out of 29 patients for IUS and 10 segments belonging to 5 patients for IDS presented a VLF modulation in QRS slopes, HRV and respiration. In these segments spectral coherence was statistically significant, while partial coherence decreased, indicating that the coupling HRV and QRS slopes was related to respiration. 4 segments had a partial coherence value below the threshold for IUS, 3 segments for IDS. The rest of the segments also presented a notable decrease in partial coherence, but still above the threshold, which means that other non-linearly effects may also affect this modulation.
JTD Keywords: diseases, electrocardiography, feature extraction, medical signal processing, pneumodynamics, statistical analysis, ECG, QRS slopes, cardiomyopathy patients, dilated cardiomyopathy, electrocardiogram, feature extraction, heart rate variability, ischemic cardiomyopathy, ordinary coherence, partial coherence value, respiration, respiratory flow signal acquisition, spectral coherence, statistical threshold, time 5 min, very low frequency modulation, Coherence, Educational institutions, Electrocardiography, Frequency modulation, Heart rate variability
Gonzalez, H., Acevedo, H., Arizmendi, C., Giraldo, B. F., (2013). Methodology for determine the moment of disconnection of patients of the mechanical ventilation using discrete wavelet transform Complex Medical Engineering (CME)
2013 ICME International Conference , IEEE (Beijing, China) , 483-486
The process of weaning from mechanical ventilation is one of the challenges in intensive care units. 66 patients under extubation process (T-tube test) were studied: 33 patients with successful trials and 33 patients who failed to maintain spontaneous breathing and were reconnected. Each patient was characterized using 7 time series from respiratory signals, and for each serie was evaluated the discrete wavelet transform. It trains a neural network for discriminating between patients from the two groups.
JTD Keywords: discrete wavelet transforms, neural nets, patient treatment, pneumodynamics, time series, ventilation, T-tube test, discrete wavelet transform, extubation process, intensive care units, mechanical ventilation, moment of disconnection, neural network, patients, respiratory signals, spontaneous breathing, time series, weaning, Mechanical Ventilation, Neural Networks, Time series from respiratory signals, Wavelet Transform
Jané, R., Lazaro, J., Ruiz, P., Gil, E., Navajas, D., Farre, R., Laguna, P., (2013). Obstructive Sleep Apnea in a rat model: Effects of anesthesia on autonomic evaluation from heart rate variability measures CinC 2013
Computing in Cardiology Conference (CinC) , IEEE (Zaragoza, Spain) , 1011-1014
Rat model of Obstructive Sleep Apnea (OSA) is a realistic approach for studying physiological mechanisms involved in sleep. Rats are usually anesthetized and autonomic nervous system (ANS) could be blocked. This study aimed to assess the effect of anesthesia on ANS activity during OSA episodes. Seven male Sprague-Dawley rats were anesthetized intraperitoneally with urethane (1g/kg). The experiments were conducted applying airway obstructions, simulating 15s-apnea episodes for 15 minutes. Five signals were acquired: respiratory pressure and flow, SaO2, ECG and photoplethysmography (PPG). In total, 210 apnea episodes were studied. Normalized power spectrum of Pulse Rate Variability (PRV) was analyzed in the Low Frequency (LF) and High Frequency (HF) bands, for each episode in consecutive 15s intervals (before, during and after the apnea). All episodes showed changes in respiratory flow and SaO2 signal. Conversely, decreases in the amplitude fluctuations of PPG (DAP) were not observed. Normalized LF presented extremely low values during breathing (median=7,67%), suggesting inhibition of sympathetic system due to anesthetic effect. Subtle increases of LF were observed during apnea. HRV and PPG analysis during apnea could be an indirect tool to assess the effect and deep of anesthesia.
JTD Keywords: electrocardiography, fluctuations, medical disorders, medical signal detection, medical signal processing, neurophysiology, photoplethysmography, pneumodynamics, sleep, ECG, SaO2 flow, SaO2 signal, airway obstructions, amplitude fluctuations, anesthesia effects, anesthetized nervous system, autonomic evaluation, autonomic nervous system, breathing, heart rate variability, high-frequency bands, low-frequency bands, male Sprague-Dawley rats, normalized power spectrum, obstructive sleep apnea, photoplethysmography, physiological mechanisms, pulse rate variability, rat model, respiratory flow, respiratory pressure, signal acquisition, sympathetic system inhibition, time 15 min, time 15 s, Abstracts, Atmospheric modeling, Computational modeling, Electrocardiography, Rats, Resonant frequency
Giraldo, B. F., Tellez, J. P., Herrera, S., Benito, S., (2013). Study of the oscillatory breathing pattern in elderly patients Engineering in Medicine and Biology Society (EMBC)
35th Annual International Conference of the IEEE , IEEE (Osaka, Japan) , 5228-5231
Some of the most common clinical problems in elderly patients are related to diseases of the cardiac and respiratory systems. Elderly patients often have altered breathing patterns, such as periodic breathing (PB) and Cheyne-Stokes respiration (CSR), which may coincide with chronic heart failure. In this study, we used the envelope of the respiratory flow signal to characterize respiratory patterns in elderly patients. To study different breathing patterns in the same patient, the signals were segmented into windows of 5 min. In oscillatory breathing patterns, frequency and time-frequency parameters that characterize the discriminant band were evaluated to identify periodic and non-periodic breathing (PB and nPB). In order to evaluate the accuracy of this characterization, we used a feature selection process, followed by linear discriminant analysis. 22 elderly patients (7 patients with PB and 15 with nPB pattern) were studied. The following classification problems were analyzed: patients with either PB (with and without apnea) or nPB patterns, and patients with CSR versus PB, CSR versus nPB and PB versus nPB patterns. The results showed 81.8% accuracy in the comparisons of nPB and PB patients, using the power of the modulation peak. For the segmented signal, the power of the modulation peak, the frequency variability and the interquartile ranges provided the best results with 84.8% accuracy, for classifying nPB and PB patients.
JTD Keywords: cardiovascular system, diseases, feature extraction, geriatrics, medical signal processing, oscillations, pneumodynamics, signal classification, time-frequency analysis, Cheyne-Stokes respiration, apnea, cardiac systems, chronic heart failure, classification problems, discriminant band, diseases, elderly patients, feature selection process, frequency variability, interquartile ranges, linear discriminant analysis, nonperiodic breathing, oscillatory breathing pattern, periodic breathing, respiratory How signal, respiratory systems, signal segmentation, time 5 min, time-frequency parameters, Accuracy, Aging, Frequency modulation, Heart, Senior citizens, Time-frequency analysis
Gilbert, M., Juárez, A., Madrid, C., Balsalobre, C., (2013). New insights in the role of HtdA in the regulation of R27 conjugation Plasmid
International Society for Plasmid Biology Meeting , Elsevier (Santander, Spain) 70 (1), 61-68
R27 is the prototype of the IncHI group of conjugative plasmids, which are associated with multidrug resistance in several relevant pathogens. The transfer of this plasmid is thermodependent and all transfer-related genes are encoded in six operons (tra operons). Very little is known about the factors involved in the regulation of the R27 conjugation. This report describes transcriptional studies of the six tra operons. Our results indicate that HtdA, encoded in the R27 plasmid, is involved in the transcriptional repression of four tra operons (F, H, AC and Z). Although HtdA plays a pivotal role in the transcriptional regulation of those operons, it does not exert its effect as a classical repressor. The data indicate the existence of a crosstalk between HtdA and other unknown regulatory factors. The HtdA-mediated regulation of conjugation is independent of the R27 H-NS protein.
JTD Keywords: Plasmid conjugation, IncHI, R27, tra Operons regulation, HtdA
Esquivel, Juan Pablo , Castellarnau, Marc , Senn, Tobias , Löchel, Bernd , Samitier, Josep , Sabaté, Neus , (2012). Fuel cell-powered microfluidic platform for lab-on-a-chip applications Lab on a Chip 12, (1), 74-79
The achievement of a higher degree of integration of components – especially micropumps and power sources – is a challenge currently being pursued to obtain portable and totally autonomous microfluidic devices. This paper presents the integration of a micro direct methanol fuel cell (mDMFC) in a microfluidic platform as a smart solution to provide both electrical and pumping power to a Lab-on-a-Chip system. In this system the electric power produced by the fuel cell is available to enable most of the functionalites required by the microfluidic chip, while the generated CO2 from the electrochemical reaction produces a pressure capable of pumping a liquid volume through a microchannel. The control of the fuel cell operating conditions allows regulation of the flow rate of a liquid sample through a microfluidic network. The relation between sample flow rate and the current generated by the fuel cell is practically linear, achieving values in the range of 4–18 mL min 1 while having an available power between 1–4 mW. This permits adjusting the desired flow rate for a given application by controlling the fuel cell output conditions and foresees a fully autonomous analytical Lab-on-a-Chip in which the same device would provide the electrical power to a detection module and at the same time use the CO2 pumping action to flow the required analytes through a particular microfluidic design.
JTD Keywords: micro direct methanol fuel cell (mDMFC), Lab-on-a-chip (LOC), Microfluidic device
Yang, Cheng, Lates, Vasilica, Prieto-Simón, Beatriz, Marty, Jean-Louis, Yang, Xiurong, (2012). Aptamer-DNAzyme hairpins for biosensing of Ochratoxin A Biosensors and Bioelectronics 32, (1), 208-212
We report an aptasensor for biosensing of Ochratoxin A (OTA) using aptamer-DNAzyme hairpin as biorecognition element. The structure of this engineered nucleic acid includes the horseradish peroxidase (HRP)-mimicking DNAzyme and the OTA specific aptamer sequences. A blocking tail captures a part of these sequences in the stem region of the hairpin. In the presence of OTA, the hairpin is opened due to the formation of the aptamer–analyte complex. As a result, self-assembly of the active HRP-mimicking DNAzyme occurs. The activity of this DNAzyme is linearly correlated with OTA concentration up to 10 nM, showing a limit of detection of 2.5 nM.
JTD Keywords: Ochratoxin A, Aptamer, G-quadruplex, DNAzyme, Hairpin
Gustavsson, J., Ginebra, M. P., Planell, J., Engel, E., (2012). Electrochemical microelectrodes for improved spatial and temporal characterization of aqueous environments around calcium phosphate cements Acta Biomaterialia 8, (1), 386-393
Calcium phosphate compounds can potentially influence cellular fate through ionic substitutions. However, to be able to turn such solution-mediated processes into successful directors of cellular response, a perfect understanding of the material-induced chemical reactions in situ is required. We therefore report on the application of home-made electrochemical microelectrodes, tested as pH and chloride sensors, for precise spatial and temporal characterization of different aqueous environments around calcium phosphate-based biomaterials prepared from α-tricalcium phosphate using clinically relevant liquid to powder ratios. The small size of the electrodes allowed for online measurements in traditionally inaccessible in vitro environments, such as the immediate material-liquid interface and the interior of curing bone cement. The kinetic data obtained has been compared to theoretical sorption models, confirming that the proposed setup can provide key information for improved understanding of the biochemical environment imposed by chemically reactive biomaterials.
JTD Keywords: Calcium phosphate, Hydroxyapatite, Ion sorption, Iridium oxide, Sensors, Animals, Biocompatible Materials, Bone Cements, Calcium Phosphates, Cells, Cultured, Chlorides, Electrochemical Techniques, Gold, Hydrogen-Ion Concentration, Hydroxyapatites, Iridium, Materials Testing, Microelectrodes, Powders, Silver, Silver Compounds, Water
Tort, N., Salvador, J. P., Avino, A., Eritja, R., Comelles, J., Martinez, E., Samitier, J., Marco, M. P., (2012). Synthesis of steroid-oligonucleotide conjugates for a DNA site-encoded SPR immunosensor
Bioconjugate Chemistry , 23, (11), 2183-2191
The excellent self-assembling properties of DNA and the excellent specificity of the antibodies to detect analytes of small molecular weight under competitive conditions have been combined in this study. Three oligonucleotide sequences (N(1)up, N(2)up, and N(3)up) have been covalently attached to three steroidal haptens (8, hG, and 13) of three anabolic-androgenic steroids (AAS), stanozolol (ST), tetrahydrogestrinone (THG), and boldenone (B), respectively. The synthesis of steroid oligonucleotide conjugates has been performed by the reaction of oligonucleotides carrying amino groups with carboxyl acid derivatives of steroidal haptens. Due to the chemical nature of the steroid derivatives, two methods for coupling the haptens and the ssDNA have been studied: a solid-phase coupling strategy and a solution-phase coupling strategy. Specific antibodies against ST, THG, and B have been used in this study to asses the possibility of using the self-assembling properties of the DNA to prepare biofunctional SPR gold chips based on the immobilization of haptens, by hybridization with the complementary oligonucleotide strands possessing SH groups previously immobilized. The capture of the steroid oligonucleotide conjugates and subsequent binding of the specific antibodies can be monitored on the sensogram due to variations produced on the refractive index on top of the gold chip. The resulting steroid oligonucleotide conjugates retain the hybridization and specific binding properties of oligonucleotides and haptens as demonstrated by thermal denaturation experiments and surface plasmon resonance (SPR).
JTD Keywords: Directed protein immobilization, Plasmon resonance biosensor, Self-assembled monolayers, Label-free, Serum samples, Assay, Immunoassays, Antibodies, Progress, Binding
Hoyo, J., Torrent-Burgués, J., Guaus, E., (2012). Biomimetic monolayer films of monogalactosyldiacylglycerol incorporating ubiquinone
Journal of Colloid and Interface Science , 384, (1), 189-197
Ubiquinone and plastoquinone are two of the main electron and proton shuttle molecules in biological systems, and monogalactosyldiacylglycerol (MGDG) is the most abundant lipid in the thylakoid membrane of chloroplasts. Saturated MGDG, ubiquinone-10 (UQ) and MGDG:UQ mixed monolayers at the air/water interface have been studied using surface pressure-area isotherms and Brewster Angle Microscopy. Moreover, the transferred Langmuir-Blodgett films have been observed by Atomic Force Microscopy. The results show that MGDG:UQ mixtures present more fluid phase than pure MGDG, indicating a higher order degree for the later. It is also observed an important influence of UQ on the MGDG matrix before UQ collapse pressure and a low influence after this event, due to UQ expulsion from the MGDG matrix. This expulsion leads to a similar remaining UQ content for all the tested mixtures, indicating a limiting content of this molecule in the MGDG matrix at high surface pressures. The thermodynamic studies confirm the stability of the MGDG:UQ mixtures at low surface pressures, although presenting a non-ideal behaviour. Results point to consider UQ as a good candidate for studies of artificial photosynthesis.
JTD Keywords: AFM, BAM, Biomimetic films, Langmuir-Blodgett film, Monogalactosyldiacylglycerol, Ubiquinone
Hoyo, J., Guaus, E., Torrent-Burgués, J., Sanz, F., (2012). Electrochemical behaviour of mixed LB films of ubiquinone - DPPC
Journal of Electroanalytical Chemistry , 669, 6-13
The structure and the electrochemical behaviour of Langmuir and Langmuir-Blodgett (LB) films of the biological ubiquinone-10 (UQ) and a mixture of dipalmytoilphosphatidylcholine (DPPC) and UQ at the molar ratios DPPC:UQ 5:1 and 10:1 have been investigated. The surface pressure-area isotherms of the Langmuir films and the AFM images of the LB films show the formation of a monolayer in the DPPC:UQ mixture till a certain surface pressure is attained, and then at higher surface pressures the UQ is progressively expelled. The cyclic voltammograms of DPPC:UQ LB films formed on indium tin oxide, ITO, at different surface pressures show one reduction and one oxidation peak at low surface pressures, but two or even more reduction and oxidations peaks at medium and high surface pressures. The electrochemical behaviour is correlated with the film structure.
JTD Keywords: Cyclic voltammetry, Electron transfer, Langmuir-Blodgett, Lipid monolayer, Modified ITO electrode, Ubiquinone
Giraldo, B.F., Gaspar, B.W., Caminal, P., Benito, S., (2012). Analysis of roots in ARMA model for the classification of patients on weaning trials Engineering in Medicine and Biology Society (EMBC)
34th Annual International Conference of the IEEE , IEEE (San Diego, USA) , 698-701
One objective of mechanical ventilation is the recovery of spontaneous breathing as soon as possible. Remove the mechanical ventilation is sometimes more difficult that maintain it. This paper proposes the study of respiratory flow signal of patients on weaning trials process by autoregressive moving average model (ARMA), through the location of poles and zeros of the model. A total of 151 patients under extubation process (T-tube test) were analyzed: 91 patients with successful weaning (GS), 39 patients that failed to maintain spontaneous breathing and were reconnected (GF), and 21 patients extubated after the test but before 48 hours were reintubated (GR). The optimal model was obtained with order 8, and statistical significant differences were obtained considering the values of angles of the first four poles and the first zero. The best classification was obtained between GF and GR, with an accuracy of 75.3% on the mean value of the angle of the first pole.
JTD Keywords: Analytical models, Biological system modeling, Computational modeling, Estimation, Hospitals, Poles and zeros, Ventilation, Autoregressive moving average processes, Patient care, Patient monitoring, Pneumodynamics, Poles and zeros, Ventilation, ARMA model, T-tube test, Autoregressive moving average model, Extubation process, Mechanical ventilation, Optimal model, Patient classification, Respiratory flow signal, Roots, Spontaneous breathing, Weaning trials
Sarlabous, L., Torres, A., Fiz, J. A., Morera, J., Jané, R., (2012). Evaluation and adaptive attenuation of the cardiac vibration interference in mechanomyographic signals Engineering in Medicine and Biology Society (EMBC)
34th Annual International Conference of the IEEE , IEEE (San Diego, USA) , 3400-3403
The study of the mechanomyographic signal of the diaphragm muscle (MMGdi) is a promising technique in order to evaluate the respiratory muscles effort. The relationship between amplitude and frequency parameters of this signal with the respiratory effort performed during respiration is of great interest for researchers and physicians due to its diagnostic potentials. However, MMGdi signals are frequently contaminated by a cardiac vibration or mechanocardiographic (MCG) signal. An adaptive noise cancellation (ANC) can be used to reduce the MCG interference in the recorded MMGdi activity. In this paper, it is evaluated the proposed ANC scheme by means of a synthetic MMGdi signal with a controlled MCG interference. The Pearson's correlation coefficient (PCC) between both root mean square (RMS) and mean frequency (fm) of the synthetic MMGdi signal are considerably reduced with the presence of cardiac vibration noise (from 0.95 to 0.87, and from 0.97 to 0.76, respectively). With the ANC algorithm proposed the effect of the MCG noise on the amplitude and frequency of MMG parameters is reduced considerably (PCC of 0.93 and 0.97 for the RMS and fm, respectively). The ANC method proposed in this work is an interesting technique to attenuate the cardiac interference in respiratory MMG signals. Further investigation should be carried out to evaluate the performance of the ANC algorithm in real MMGdi signals.
JTD Keywords: Adaptive filters, Frequency modulation, Interference, Muscles, Noise cancellation, Vibrations, Cardiology, Medical signal processing, Muscle, Signal denoising, ANC algorithm, MCG interference, Pearson correlation coefficient, Adaptive noise cancellation, Cardiac vibration interference, Cardiac vibration noise, Diaphragm muscle, Mechanocardiographic signal, Mechanomyographic signals, Respiratory muscles effort
Chaparro, J.A., Giraldo, B.F., Caminal, P., Benito, S., (2012). Performance of respiratory pattern parameters in classifiers for predict weaning process Engineering in Medicine and Biology Society (EMBC)
34th Annual International Conference of the IEEE , IEEE (San Diego, USA) , 4349-4352
Weaning trials process of patients in intensive care units is a complex clinical procedure. 153 patients under extubation process (T-tube test) were studied: 94 patients with successful trials (group S), 38 patients who failed to maintain spontaneous breathing and were reconnected (group F), and 21 patients with successful test but that had to be reintubated before 48 hours (group R). The respiratory pattern of each patient was characterized through the following time series: inspiratory time (TI), expiratory time (TE), breathing cycle duration (TTot), tidal volume (VT), inspiratory fraction (TI/TTot), half inspired flow (VT/TI), and rapid shallow index (f/VT), where f is respiratory rate. Using techniques as autoregressive models (AR), autoregressive moving average models (ARMA) and autoregressive models with exogenous input (ARX), the most relevant parameters of the respiratory pattern were obtained. We proposed the evaluation of these parameters using classifiers as logistic regression (LR), linear discriminant analysis (LDA), support vector machines (SVM) and classification and regression tree (CART) to discriminate between patients from groups S, F and R. An accuracy of 93% (98% sensitivity and 82% specificity) has been obtained using CART classification.
JTD Keywords: Accuracy, Indexes, Logistics, Regression tree analysis, Support vector machines, Time series analysis, Autoregressive moving average processes, Medical signal processing, Pattern classification, Pneumodynamics, Regression analysis, Sensitivity, Signal classification, Support vector machines, Time series, SVM, T-tube testing, Autoregressive models-with-exogenous input, Autoregressive moving average models, Breathing cycle duration, Classification-and-regression tree, Expiratory time, Extubation process, Half inspired flow, Inspiratory fraction, Inspiratory time, Intensive care units, Linear discriminant analysis, Logistic regression, Rapid shallow index, Respiratory pattern parameter performance, Sensitivity, Spontaneous breathing, Support vector machines, Tidal volume, Time 48 hr, Time series, Weaning process classifiers
Garde, A., Giraldo, B.F., Jané, R., Latshang, T.D., Turk, A.J., Hess, T., Bosch, M-.M., Barthelmes, D., Hefti, J.P., Maggiorini, M., Hefti, U., Merz, T.M., Schoch, O.D., Bloch, K.E., (2012). Periodic breathing during ascent to extreme altitude quantified by spectral analysis of the respiratory volume signal Engineering in Medicine and Biology Society (EMBC)
34th Annual International Conference of the IEEE , IEEE (San Diego, USA) , 707-710
High altitude periodic breathing (PB) shares some common pathophysiologic aspects with sleep apnea, Cheyne-Stokes respiration and PB in heart failure patients. Methods that allow quantifying instabilities of respiratory control provide valuable insights in physiologic mechanisms and help to identify therapeutic targets. Under the hypothesis that high altitude PB appears even during physical activity and can be identified in comparison to visual analysis in conditions of low SNR, this study aims to identify PB by characterizing the respiratory pattern through the respiratory volume signal. A number of spectral parameters are extracted from the power spectral density (PSD) of the volume signal, derived from respiratory inductive plethysmography and evaluated through a linear discriminant analysis. A dataset of 34 healthy mountaineers ascending to Mt. Muztagh Ata, China (7,546 m) visually labeled as PB and non periodic breathing (nPB) is analyzed. All climbing periods within all the ascents are considered (total climbing periods: 371 nPB and 40 PB). The best crossvalidated result classifying PB and nPB is obtained with Pm (power of the modulation frequency band) and R (ratio between modulation and respiration power) with an accuracy of 80.3% and area under the receiver operating characteristic curve of 84.5%. Comparing the subjects from 1st and 2nd ascents (at the same altitudes but the latter more acclimatized) the effect of acclimatization is evaluated. SaO2 and periodic breathing cycles significantly increased with acclimatization (p-value <; 0.05). Higher Pm and higher respiratory frequencies are observed at lower SaO2, through a significant negative correlation (p-value <; 0.01). Higher Pm is observed at climbing periods visually labeled as PB with >; 5 periodic breathing cycles through a significant positive correlation (p-value <; 0.01). Our data demonstrate that quantification of the respiratory volum- signal using spectral analysis is suitable to identify effects of hypobaric hypoxia on control of breathing.
JTD Keywords: Frequency domain analysis, Frequency modulation, Heart, Sleep apnea, Ventilation, Visualization, Cardiology, Medical disorders, Medical signal processing, Plethysmography, Pneumodynamics, Sensitivity analysis, Sleep, Spectral analysis, Cheyne-Stokes respiration, Climbing periods, Dataset, Heart failure patients, High altitude PB, High altitude periodic breathing, Hypobaric hypoxia, Linear discriminant analysis, Pathophysiologic aspects, Physical activity, Physiologic mechanisms, Power spectral density, Receiver operating characteristic curve, Respiratory control, Respiratory frequency, Respiratory inductive plethysmography, Respiratory pattern, Respiratory volume signal, Sleep apnea, Spectral analysis, Spectral parameters
Mesquita, J., Poree, F., Carrault, G., Fiz, J. A., Abad, J., Jané, R., (2012). Respiratory and spontaneous arousals in patients with Sleep Apnea Hypopnea Syndrome Engineering in Medicine and Biology Society (EMBC)
34th Annual International Conference of the IEEE , IEEE (San Diego, USA) , 6337-6340
Sleep in patients with Sleep Apnea-Hypopnea Syndrome (SAHS) is frequently interrupted with arousals. Increased amounts of arousals result in shortening total sleep time and repeated sleep-arousal change can result in sleep fragmentation. According to the American Sleep Disorders Association (ASDA) an arousal is a marker of sleep disruption representing a detrimental and harmful feature for sleep. The nature of arousals and its role on the regulation of the sleep process raises controversy and has sparked the debate in the last years. In this work, we analyzed and compared the EEG spectral content of respiratory and spontaneous arousals on a database of 45 SAHS subjects. A total of 3980 arousals (1996 respiratory and 1984 spontaneous) were analyzed. The results showed no differences between the spectral content of the two kinds of arousals. Our findings raise doubt as to whether these two kinds of arousals are truly triggered by different organic mechanisms. Furthermore, they may also challenge the current beliefs regarding the underestimation of the importance of spontaneous arousals and their contribution to sleep fragmentation in patients suffering from SAHS.
JTD Keywords: Adaptive filters, Correlation, Databases, Electroencephalography, Hospitals, Sleep apnea, Electroencephalography, Medical signal processing, Pneumodynamics, Sleep, EEG spectral content, Organic mechanism, Respiratory, Sleep apnea hypopnea syndrome, Sleep fragmentation, Spectral content, Spontaneous arousal
Amigo, L. E., Fernandez, Q., Giralt, X., Casals, A., Amat, J., (2012). Study of patient-orthosis interaction forces in rehabilitation therapies IEEE Conference Publications
4th IEEE RAS & EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob) , IEEE (Roma, Italy) , 1098-1103
The design of mechanical joints that kinematically behave as their biological counterparts is a challenge that if not addressed properly can cause inadequate forces transmission between robot and patient. This paper studies the interaction forces in rehabilitation therapies of the elbow joint. To measure the effect of orthosis-patient misalignments, a force sensor with a novel distributed architecture has been designed and used for this study. A test-bed based on an industrial robot acting as a virtual exoskeleton that emulates the action of a therapist has been developed and the interaction forces analyzed.
JTD Keywords: Force, Force measurement, Force sensors, Joints, Medical treatment, Robot sensing systems, Force sensors, Medical robotics, Patient rehabilitation, Biological counterparts, Distributed architecture, Elbow joint, Force sensor, Inadequate forces transmission, Industrial robot, Mechanical joints design, Orthosis-patient misalignments, Patient-orthosis interaction forces, Rehabilitation therapies, Robot, Test-bed, Virtual exoskeleton
Hernansanz, A., Amat, J., Casals, A., (2012). Virtual Robot: A new teleoperation paradigm for minimally invasive robotic surgery IEEE Conference Publications
4th IEEE RAS & EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob) , IEEE (Roma, Italy) , 749-754
This paper presents a novel teleoperation paradigm, the Virtual Robot (VR), focused on facilitating the surgeon tasks in minimally invasive robotic surgery. The VR has been conceived to increase the range of applicability of traditional master slave teleoperation architectures by means of an automatic cooperative behavior that assigns the execution of the ongoing task to the most suitable robot. From the user's point of view, the VR internal operation must be automatic and transparent. A set of evaluation indexes have been developed to obtain the suitability of each robot as well as an algorithm to determine the optimal instant of time to execute a task transfer. Several experiments demonstrate the usefulness of the VR, as well as indicates the next steps of the research.
JTD Keywords: Cameras, Collision avoidance, Indexes, Joints, Robots, Surgery, Trajectory, Medical robotics, Surgery, Telerobotics, VR internal operation, Automatic cooperative behavior, Evaluation indexes, Master slave teleoperation architectures, Minimally invasive robotic surgery, Task transfer, Virtual robot
Sjoberg, B. M., Torrents, E., (2011). Shift in ribonucleotide reductase gene expression in pseudomonas aeruginosa during infection
Infection and Immunity , 79, (7), 2663-2669
The roles of different ribonucleotide reductases (RNRs) in bacterial pathogenesis have not been studied systematically. In this work we analyzed the importance of the different Pseudomonas aeruginosa RNRs in pathogenesis using the Drosophila melanogaster host-pathogen interaction model. P. aeruginosa codes for three different RNRs with different environmental requirements. Class II and III RNR chromosomal mutants exhibited reduced virulence in this model. Translational reporter fusions of RNR gene nrdA, nrdJ, or nrdD to the green fluorescent protein were constructed to measure the expression of each class during the infection process. Analysis of the P. aeruginosa infection by flow cytometry revealed increased expression of nrdJ and nrdD and decreased nrdA expression during the infection process. Expression of each RNR class fits with the pathogenicities of the chromosomal deletion mutants. An extended understanding of the pathogenicity and physiology of P. aeruginosa will be important for the development of novel drugs against infections in cystic fibrosis patients.
JTD Keywords: Broad-host-range, Anaerobic growth, Drosophila-melanogaster, Bacterial biofilms, Escherichia-coli, Cystic-fibrosis, Model host, Virulence, Promoter, Vectors
Sánchez-Martín, M. J., Urbán, P., Pujol, M., Haro, I., Alsina, M. A., Busquets, M. A., (2011). Biophysical investigations of GBV-C E1 peptides as potential inhibitors of HIV-1 fusion peptide
ChemPhysChem , 12, (15), 2816-2822
Five peptide sequences corresponding to the E1 protein of GBV-C [NCCAPEDIGFCLEGGCLV (P7), APEDIGFCLEGGCLVALG (P8), FCLEGGCLVALGCTICTD (P10), QAGLAVRPGKSAAQLVGE (P18), and AQLVGELGSLYGPLSVSA (P22)] were synthesized because they were capable of interfering with the HIV-1 fusion peptide (HIV-1 FP)-vesicle interaction. In this work the interaction of these peptides with the HIV-1 FP, as well as with membrane models, was analyzed to corroborate their inhibition ability and to understand if the interaction with the fusion peptide takes place in solution or at the membrane level. Several studies were carried out on aggregation and membrane fusion, surface Plasmon resonance, and conformational analysis by circular dichroism. Moreover, in vitro toxicity assays, including cytotoxicity studies in 3T3 fibroblasts and hemolysis assays in human red blood cells, were performed to evaluate if these peptides could be potentially used in anti-HIV-1 therapy. Results show that P10 is not capable of inhibiting membrane fusion caused by HIV-1 and it aggregates liposomes and fuses membranes, thus we decided to discard it for futures studies. P18 and P22 do not inhibit membrane fusion, but they inhibit the ability of HIV-1 FP to form pores in bilayers, thus we have not discarded them yet. P7 and P8 were selected as the best candidates for future studies because they are capable of inhibiting membrane fusion and the interaction of HIV-1 FP with bilayers. Therefore, these peptides could be potentially used in future anti-HIV-1 research. Part of the gang: Liposomes are deposited on a surface plasmon resonance chip (see AFM image of the chip) to observe the interaction of peptides corresponding to the E1 envelop protein of the hepatitis G virus with membranes to show how they reduce the interaction of the HIV-1 fusion peptide.
JTD Keywords: HIV-1 fusion protein, Liposomes, Membranes, Peptides, Viruses
Cagido, Viviane Ramos, Zin, Walter Araujo, Ramirez, Jose, Navajas, Daniel, Farre, Ramon, (2011). Alternating ventilation in a rat model of increased abdominal pressure
Respiratory Physiology & Neurobiology , 175, (3), 310-315
During alternating ventilation (AV) one lung is inflating while the other is deflating. Considering the possible respiratory and hemodynamic advantages of AV, we investigated its effects during increased intra-abdominal pressure (IAP = 10 mmHg). In Sprague-Dawley rats (n = 6, 270–375 g) the main bronchi were independently cannulated, and respiratory mechanics determined while animals underwent different ventilatory patterns: synchronic ventilation without increased IAP (SV-0), elevated IAP during SV (SV-10), and AV with elevated IAP (AV-10). Thirty-three other animals (SV-0, n = 10; SV-10, n = 11 and AV-10, n = 12) were ventilated during 3 h. Mean arterial pressure (MAP), and lung histology were assessed. Increased IAP resulted in significantly higher elastances (p < 0.001), being AV-10 lower than SV-10 (p < 0.020). SV-10 showed higher central venous pressure (p < 0.003) than S-0; no change was observed in AV-10. Wet/dry lung weight ratio was lower in AV-10 than SV-10 (p = 0.009). Application of AV reduced hemodynamic and lung impairments induced by increased IAP during SV.
JTD Keywords: Alternating ventilation, Respiratory mechanics, Intra-abdominal pressure, Hemodynamic, Mechanical ventilation, Animal model
Carreras, Alba, Wang, Yang, Gozal, David, Montserrat, Josep M., Navajas, Daniel, Farre, Ramon, (2011). Non-invasive system for applying airway obstructions to model obstructive sleep apnea in mice
Respiratory Physiology & Neurobiology , 175, (1), 164-168
Obstructive sleep apnea (OSA) is characterized by recurrent upper airway obstructions during sleep. The most common animal model of OSA is based on subjecting rodents to intermittent hypoxic exposures and does not mimic important OSA features, such as recurrent hypercapnia and increased inspiratory efforts. To circumvent some of these issues, a novel murine model involving non-invasive application of recurrent airway obstructions was developed. An electronically controlled airbag system is placed in front of the mouse's snout, whereby inflating the airbag leads to obstructed breathing and spontaneous breathing occurs with the airbag deflated. The device was tested on 29 anesthetized mice by measuring inspiratory effort and arterial oxygen saturation (SaO(2)). Application of recurrent obstructive apneas (6s each, 120/h) for 6h resulted in SaO(2) oscillations to values reaching 84.4 +/- 2.5% nadir, with swings mimicking OSA patients. This novel system, capable of applying controlled recurrent airway obstructions in mice, is an easy-to-use tool for investigating pertinent aspects of OSA.
JTD Keywords: Animal model, Upper airway Obstruction, Mouse model, Non-invasive system, Model sleep apnea, Respiratory disease
Rodríguez, J. E., Cruz, I., Vergés, E., Ayala, D., (2011). A connected-component-labeling-based approach to virtual porosimetry
Graphical Models , 73, (5), 296-310
Analyzing the pore-size distribution of porous materials, made up of an aggregation of interconnected pores, is a demanding task. Mercury intrusion porosimetry (MIP) is a physical method that intrudes mercury into a sample at increasing pressures to obtain a pore-size histogram. This method has been simulated in-silice with several approaches requiring prior computation of a skeleton. We present a new approach to simulate MIP that does not require skeleton computation. Our method is an iterative process that considers the diameters corresponding to pressures. At each iteration, geometric tests detect throats for the corresponding diameter and a CCL process collects the region invaded by the mercury. Additionally, a new decomposition model called CUDB, is used. This is suitable for computing the throats and performs better with the CCL algorithm than a voxel model. Our approach obtains the pore-size distribution of the porous medium, and the corresponding pore graph.
JTD Keywords: Micro CT, Pore map, Porous media, Skeleton, Virtual MIP
Punter-Villagrasa, J., Colomer-Farrarons, J., Miribel-Catala, P., Puig-Vidal, M., Samitier, J., (2011). Discrete to full custom ASIC solutions for bioelectronic applications Proceedings of the SPIE - The International Society for Optical Engineering
VLSI Circuits and Systems V , SPIE - The International Society for Optical Engineering (Prague, Czech Republic) 8067, 80670Q
This paper presents a first approach on multi-pathogen detection system for portable point-of-care applications on discrete electronics field. The main interest is focused on the development of custom built electronic solutions for bioelectronics applications, from discrete devices to ASICS solutions.
JTD Keywords: Application specific integrated circuits, Biomedical electronics, Biosensors
Ziyatdinov, Andrey, Fernandez-Diaz, Eduard, Chaudry, A., Marco, Santiago, Persaud, Krishna, Perera, Alexandre, (2011). A large scale virtual gas sensor array Olfaction and Electronic Nose: Proceedings of the 14th International Symposium on Olfaction and Electronic Nose
AIP Conference Proceedings (ed. Perena Gouma, SUNY Stony Brook), AIP (New York City, USA) 1362, (1), 151-152
This paper depicts a virtual sensor array that allows the user to generate gas sensor synthetic data while controlling a wide variety of the characteristics of the sensor array response: arbitrary number of sensors, support for multi-component gas mixtures and full control of the noise in the system such as sensor drift or sensor aging. The artificial sensor array response is inspired on the response of 17 polymeric sensors for three analytes during 7 month. The main trends in the synthetic gas sensor array, such as sensitivity, diversity, drift and sensor noise, are user controlled. Sensor sensitivity is modeled by an optionally linear or nonlinear method (spline based). The toolbox on data generation is implemented in open source R language for statistical computing and can be freely accessed as an educational resource or benchmarking reference. The software package permits the design of scenarios with a very large number of sensors (over 10000 sensels), which are employed in the test and benchmarking of neuromorphic models in the Bio-ICT European project NEUROCHEM.
JTD Keywords: Data analysis, Circuit noise, Data acquisition, Signal processing
Mateos-Timoneda, M. A., Planell, J. A., Engel, E., (2011). Modifying biomaterial surfaces for the repair and regeneration of nerve cells
Surface Modification of Biomaterials: Methods Analysis and Applications (ed. Williams, R.), Woodhead Publishing (Cambridge, UK) , 325-343
This chapter discusses the use of chemical and topographical modification of biomaterials in the field of repair and regeneration of nerve tissue. The chapter first reviews briefly the methods developed to chemically and topographically modify the surface of biomaterials. The chapter then discusses how these modified surfaces interact with nerve cells and guide cellular activities.
JTD Keywords: Chemical modification, Nerve repair, Topographical modification
Santoro, R., Olivares, A. L., Brans, G., Wirz, D., Longinotti, C., Lacroix, D., Martin, I., Wendt, D., (2010). Bioreactor based engineering of large-scale human cartilage grafts for joint resurfacing Biomaterials 31, (34), 8946-8952
Apart from partial or total joint replacement, no surgical procedure is currently available to treat large and deep cartilage defects associated with advanced diseases such as osteoarthritis. In this work, we developed a perfusion bioreactor system to engineer human cartilage grafts in a size with clinical relevance for unicompartmental resurfacing of human knee joints (50 mm diameter x 3 mm thick). Computational fluid dynamics models were developed to optimize the flow profile when designing the perfusion chamber. Using the developed system, human chondrocytes could be seeded throughout large 50 mm diameter scaffolds with a uniform distribution. Following two weeks culture, tissues grown in the bioreactor were viable and homogeneously cartilaginous, with biomechanical properties approaching those of native cartilage. In contrast, tissues generated by conventional manual production procedures were highly inhomogeneous and contained large necrotic regions. The unprecedented engineering of human cartilage tissues in this large-scale opens the practical perspective of grafting functional biological substitutes for the clinical treatment for extensive cartilage defects, possibly in combination with surgical or pharmacological therapies to support durability of the implant. Ongoing efforts are aimed at integrating the up-scaled bioreactor based processes within a fully automated and closed manufacturing system for safe, standardized, and GMP compliant production of large-scale cartilage grafts.
JTD Keywords: Bioreactor, Cartilage repair, Computational fluid dynamics, Scale-up, Regenerative medicine, Tissue engineering
Iranzo, A., Isetta, V., Molinuevo, J. L., Serradell, M., Navajas, D., Farre, R., Santamaria, J., (2010). Electroencephalographic slowing heralds mild cognitive impairment in idiopathic REM sleep behavior disorder
Sleep Medicine , 11, (6), 534-539
Objective: Patients with idiopathic rapid eye movement (REM) sleep behavior disorder (IRBD) may show electroencephalographic (EEG) slowing reflecting cortical dysfunction and are at risk for developing neurological conditions characterized by cognitive dysfunction including mild cognitive impairment (MCI), dementia with Lewy bodies and Parkinson's disease with associated dementia. We hypothesized that those IRBD patients who later developed MCI had pronounced cortical EEG slowing at presentation. Methods: Power EEG spectral analysis was blindly quantified from the polysomnographic studies of 23 IRBD patients without cognitive complaints and 10 healthy controls without RBD. After a mean clinical follow-up of 2.40 +/- 1.55 years, 10 patients developed MCI (RBD + MCI) and the remaining 13 remained idiopathic. Results: Patients with RBD + MCI had marked EEG slowing (increased delta and theta activity) in central and occipital regions during wakefulness and REM sleep, particularly in the right hemisphere, when compared with controls and, to a lesser extent, with IRBD subjects who remained idiopathic. The EEG spectral pattern of the RBD + MCI group was similar to that seen in patients with dementia with Lewy bodies and Parkinson's disease associated with dementia. Conclusion: Our findings suggest that the presence of marked EEG slowing on spectral analysis might be indicative of the short-term development of MCI in patients initially diagnosed with IRBD.
JTD Keywords: Idiopathic REM sleep behavior disorder, Power EEG spectral analysis, Mild cognitive impairment, REM sleep, Parkinson's disease, Dementia with Lewy bodies
Johansson, R., Torrents, E., Lundin, D., Sprenger, J., Sahlin, M., Sjöberg, B. M., Logan, D. T., (2010). High-resolution crystal structures of the flavoprotein NrdI in oxidized and reduced states – an unusual flavodoxin
FEBS Journal , 277, (20), 4265-4277
The small flavoprotein NrdI is an essential component of the class Ib ribonucleotide reductase system in many bacteria. NrdI interacts with the class Ib radical generating protein NrdF. It is suggested to be involved in the rescue of inactivated diferric centres or generation of active dimanganese centres in NrdF. Although NrdI bears a superficial resemblance to flavodoxin, its redox properties have been demonstrated to be strikingly different. In particular, NrdI is capable of two-electron reduction, whereas flavodoxins are exclusively one-electron reductants. This has been suggested to depend on a lesser destabilization of the negatively-charged hydroquinone state than in flavodoxins. We have determined the crystal structures of NrdI from Bacillus anthracis, the causative agent of anthrax, in the oxidized and semiquinone forms, at resolutions of 0.96 and 1.4 Å, respectively. These structures, coupled with analysis of all curated NrdI sequences, suggest that NrdI defines a new structural family within the flavodoxin superfamily. The conformational behaviour of NrdI in response to FMN reduction is very similar to that of flavodoxins, involving a peptide flip in a loop near the N5 atom of the flavin ring. However, NrdI is much less negatively charged than flavodoxins, which is expected to affect its redox properties significantly. Indeed, sequence analysis shows a remarkable spread in the predicted isoelectric points of NrdIs, from approximately pH 4–10. The implications of these observations for class Ib ribonucleotide reductase function are discussed.
JTD Keywords: Crystal structure, Flavin mononucleotide, Flavodoxin, NrdI, Ribonucleotide reductase
Carreras, A., Rojas, M., Tsapikouni, T., Montserrat, J. M., Navajas, D., Farre, R., (2010). Obstructive apneas induce early activation of mesenchymal stem cells and enhancement of endothelial wound healing
Respiratory Research , 11, (91), 1-7
Background: The aim was to test the hypothesis that the blood serum of rats subjected to recurrent airway obstructions mimicking obstructive sleep apnea (OSA) induces early activation of bone marrow-derived mesenchymal stem cells (MSC) and enhancement of endothelial wound healing. Methods: We studied 30 control rats and 30 rats subjected to recurrent obstructive apneas (60 per hour, lasting 15 s each, for 5 h). The migration induced in MSC by apneic serum was measured by transwell assays. MSC-endothelial adhesion induced by apneic serum was assessed by incubating fluorescent-labelled MSC on monolayers of cultured endothelial cells from rat aorta. A wound healing assay was used to investigate the effect of apneic serum on endothelial repair. Results: Apneic serum showed significant increase in chemotaxis in MSC when compared with control serum: the normalized chemotaxis indices were 2.20 +/- 0.58 (m +/- SE) and 1.00 +/- 0.26, respectively (p < 0.05). MSC adhesion to endothelial cells was greater (1.75 +/- 0.14 -fold; p < 0.01) in apneic serum than in control serum. When compared with control serum, apneic serum significantly increased endothelial wound healing (2.01 +/- 0.24 -fold; p < 0.05). Conclusions: The early increases induced by recurrent obstructive apneas in MSC migration, adhesion and endothelial repair suggest that these mechanisms play a role in the physiological response to the challenges associated to OSA.
JTD Keywords: Induced acute lung, Sleep-apnea, Intermitent hypoxia, Cardiovascular-disease, Progenito Cells, Rat model, Inflammation, Mechanisms, Repair, Blood
Carreras, Alba, Almendros, Isaac, Montserrat, Josep M., Navajas, Daniel, Farre, Ramon, (2010). Mesenchymal stem cells reduce inflammation in a rat model of obstructive sleep apnea
Respiratory Physiology & Neurobiology , 172, (3), 210-212
The aim was to test the hypothesis that mesenchymal stem cells (MSC) could reduce the inflammation induced by recurrent airway occlusions in an animal model of obstructive sleep apnea (OSA). A nasal mask was applied to 30 anesthetized rats. Twenty rats were subjected to a pattern of recurrent obstructive apneas mimicking OSA (60/h, lasting 15 s each) for 5h. MSC (5x10(6) cells) were intravenously injected into 10 of these rats. Ten rats not subjected to apneas or MSC injection were used as controls. The rat blood serum concentrations of pro-inflammatory cytokine IL-1beta were measured by ELISA. IL-1beta was significantly greater in the rats subjected to recurrent apneas (66.7+/-41.2 pg/mL; m+/-SEM) than in controls (1.9+/-1.0 pg/mL; p<0.05). In the group of apneic rats subjected to MSC injection, IL-1beta was significantly reduced (6.1+/-3.8 pg/mL; p<0.05). In conclusion, MSC triggered an early anti-inflammatory response in rats subjected to recurrent obstructive apneas, suggesting that these stem cells could play a role in the physiological response to counterbalance inflammation in OSA.
JTD Keywords: Obstructive sleep apnea, Animal model, Airway obstruction, Inflammation
Garde, A., Sörnmo, L., Jané, R., Giraldo, B., (2010). Breathing pattern characterization in chronic heart failure patients using the respiratory flow signal
Annals of Biomedical Engineering , 38, (12), 3572-3580
This study proposes a method for the characterization of respiratory patterns in chronic heart failure (CHF) patients with periodic breathing (PB) and nonperiodic breathing (nPB), using the flow signal. Autoregressive modeling of the envelope of the respiratory flow signal is the starting point for the pattern characterization. Spectral parameters extracted from the discriminant frequency band (DB) are used to characterize the respiratory patterns. For each classification problem, the most discriminant parameter subset is selected using the leave-one-out cross-validation technique. The power in the right DB provides an accuracy of 84.6% when classifying PB vs. nPB patterns in CHF patients, whereas the power of the DB provides an accuracy of 85.5% when classifying the whole group of CHF patients vs. healthy subjects, and 85.2% when classifying nPB patients vs. healthy subjects.
JTD Keywords: Chronic heart failure, AR modeling, Respiratory pattern, Discriminant band, Periodic and nonperiodic breathing
Caminal, P., Giraldo, B. F., Vallverdu, M., Benito, S., Schroeder, R., Voss, A., (2010). Symbolic dynamic analysis of relations between cardiac and breathing cycles in patients on weaning trials
Annals of Biomedical Engineering , 38, (8), 2542-52
Traditional time-domain techniques of data analysis are often not sufficient to characterize the complex dynamics of the cardiorespiratory interdependencies during the weaning trials. In this paper, the interactions between the heart rate (HR) and the breathing rate (BR) were studied using joint symbolic dynamic analysis. A total of 133 patients on weaning trials from mechanical ventilation were analyzed: 94 patients with successful weaning (group S) and 39 patients that failed to maintain spontaneous breathing (group F). The word distribution matrix enabled a coarse-grained quantitative assessment of short-term nonlinear analysis of the cardiorespiratory interactions. The histogram of the occurrence probability of the cardiorespiratory words presented a higher homogeneity in group F than in group S, measured with a higher number of forbidden words in group S as well as a higher number of words whose probability of occurrence is higher than a probability threshold in group S. The discriminant analysis revealed the best results when applying symbolic dynamic variables. Therefore, we hypothesize that joint symbolic dynamic analysis provides enhanced information about different interactions between HR and BR, when comparing patients with successful weaning and patients that failed to maintain spontaneous breathing in the weaning procedure.
JTD Keywords: Dynamical nonlinearities analysis, Cardiorespiratory interdependencies, Joint symbolic dynamic, Weaning procedure
Rajzer, I., Castano, O., Engel, E., Planell, J. A., (2010). Injectable and fast resorbable calcium phosphate cement for body-setting bone grafts
Journal of Materials Science-Materials in Medicine , 21, (7), 2049-2056
In this work a calcium phosphate (CPC)/polymer blend was developed with the advantage of being moldable and capable of in situ setting to form calcium deficient hydroxyapatite under physiological conditions in an aqueous environment at body temperature. The CPC paste consists in a mix of R cement, glycerol as a liquid phase carrier and a biodegradable hydrogel such as Polyvinyl alcohol, which acts as a binder. Microstructure and mechanical analysis shows that the CPC blend can be used as an injectable implant for low loaded applications and fast adsorption requirements. The storage for commercial distribution was also evaluated and the properties of the materials obtained do not significantly change during storage at -18A degrees C.
JTD Keywords: Clinical-applications, Composites, Regeneration, Behavior, Scaffold, Repair
Morgenstern, C., Schwaibold, M., Randerath, W. J., Bolz, A., Jané, R., (2010). An invasive and a noninvasive approach for the automatic differentiation of obstructive and central hypopneas IEEE Transactions on Biomedical Engineering 57, (8), 1927-1936
The automatic differentiation of obstructive and central respiratory events is a major challenge in the diagnosis of sleep-disordered breathing. Esophageal pressure (Pes) measurement is the gold-standard method to identify these events. This study presents a new classifier that automatically differentiates obstructive and central hypopneas with the Pes signal and a new approach for an automatic noninvasive classifier with nasal airflow. An overall of 28 patients underwent night polysomnography with Pes recording, and a total of 769 hypopneas were manually scored by human experts to create a gold-standard annotation set. Features were automatically extracted from the Pes signal to train and test the classifiers (discriminant analysis, support vector machines, and adaboost). After a significantly (p < 0.01) higher incidence of inspiratory flow limitation episodes in obstructive hypopneas was objectively, invasively assessed compared to central hypopneas, the feasibility of an automatic noninvasive classifier with features extracted from the airflow signal was demonstrated. The automatic invasive classifier achieved a mean sensitivity, specificity, and accuracy of 0.90 after a 100-fold cross validation. The automatic noninvasive feasibility study obtained similar hypopnea differentiation results as a manual noninvasive classification algorithm. Hence, both systems seem promising for the automatic differentiation of obstructive and central hypopneas.
JTD Keywords: Automatic differentiation, Central hypopnea, Esophageal pressure (Pes), Inspiratory flow limitation (IFL), Noninvasive classification, Obstructive hypopnea
Morgenstern, C., Schwaibold, M., Randerath, W., Bolz, A., Jané, R., (2010). Automatic non-invasive differentiation of obstructive and central hypopneas with nasal airflow compared to esophageal pressure Engineering in Medicine and Biology Society (EMBC)
32nd Annual International Conference of the IEEE , IEEE (Buenos Aires, Argentina) , 6142-6145
The differentiation of obstructive and central respiratory events is a major challenge in the diagnosis of sleep disordered breathing. Esophageal pressure (Pes) measurement is the gold-standard method to identify these events but its invasiveness deters its usage in clinical routine. Flattening patterns appear in the airflow signal during episodes of inspiratory flow limitation (IFL) and have been shown with invasive techniques to be useful to differentiate between central and obstructive hypopneas. In this study we present a new method for the automatic non-invasive differentiation of obstructive and central hypopneas solely with nasal airflow. An overall of 36 patients underwent full night polysomnography with systematic Pes recording and a total of 1069 hypopneas were manually scored by human experts to create a gold-standard annotation set. Features were automatically extracted from the nasal airflow signal to train and test our automatic classifier (Discriminant Analysis). Flattening patterns were non-invasively assessed in the airflow signal using spectral and time analysis. The automatic non-invasive classifier obtained a sensitivity of 0.71 and an accuracy of 0.69, similar to the results obtained with a manual non-invasive classification algorithm. Hence, flattening airflow patterns seem promising for the non-invasive differentiation of obstructive and central hypopneas.
JTD Keywords: Practical, Experimental/ biomedical measurement, Feature extraction, Flow measurement, Medical disorders, Medical signal processing, Patient diagnosis, Pneumodynamics, Pressure measurement, Signal classification, Sleep, Spectral analysis/ automatic noninvasive differentiation, Obstructive hypopnea, Central hypopnea, Inspiratory flow limitation, Nasal airflow, Esophageal pressure, Polysomnography, Feature extraction, Discriminant analysis, Spectral analysis
Garde, A., Sörnmo, L., Jané, R., Giraldo, B. F., (2010). Correntropy-based nonlinearity test applied to patients with chronic heart failure Engineering in Medicine and Biology Society (EMBC)
32nd Annual International Conference of the IEEE , IEEE (Buenos Aires, Argentina) , 2399-2402
In this study we propose the correntropy function as a discriminative measure for detecting nonlinearities in the respiratory pattern of chronic heart failure (CHF) patients with periodic or nonperiodic breathing pattern (PB or nPB, respectively). The complexity seems to be reduced in CHF patients with higher risk level. Correntropy reflects information on both, statistical distribution and temporal structure of the underlying dataset. It is a suitable measure due to its capability to preserve nonlinear information. The null hypothesis considered is that the analyzed data is generated by a Gaussian linear stochastic process. Correntropy is used in a statistical test to reject the null hypothesis through surrogate data methods. Various parameters, derived from the correntropy and correntropy spectral density (CSD) to characterize the respiratory pattern, presented no significant differences when extracted from the iteratively refined amplitude adjusted Fourier transform (IAAFT) surrogate data. The ratio between the powers in the modulation and respiratory frequency bands R was significantly different in nPB patients, but not in PB patients, which reflects a higher presence of nonlinearities in nPB patients than in PB patients.
JTD Keywords: Practical, Theoretical or Mathematical, Experimental/cardiology diseases, Fourier transforms, Medical signal processing, Pattern classification, Pneumodynamics, Spectral analysis, Statistical analysis, Stochastic processes/ correntropy based nonlinearity test, Chronic heart failure, Correntropy function, Respiratory pattern nonlinearities, CHF patients, Nonperiodic breathing pattern, Dataset statistical distribution, Dataset temporal structure, Nonlinear information, Null hypothesis, Gaussian linear stochastic process, Statistical test, Correntropy spectral density, Iteratively refined amplitude adjusted Fourier transform, Surrogate data, Periodic breathing pattern
Fernandez, L., Gutierrez-Galvez, A., Marco, S., (2010). Gas sensor array system inspired on the sensory diversity and redundancy of the olfactory epithelium Procedia Engineering
Eurosensor XXIV Conference (ed. Jakoby, B., Vellekoop, M.J.), Elsevier Science BV (Linz, Austria) 5, (0), 25-28
This paper presents a chemical sensing system that takes inspiration from the combination of sensory diversity and redundancy at the olfactory epithelium to enhance the chemical information obtained from the odorants. The system is based on commercial MOS sensors and achieves, first, diversity trough different types of MOS along with modulation of their temperatures, and second redundancy including 12 MOS sensors for each type (12×8) combined with a high-speed multiplexing system that allows connecting 16 load resistors with each and every one of the 96 sensors in about two seconds. Exposition of the system to ethanol, ammonia, and acetone at different concentrations shows how the system is able to capture a large amount of information of the identity and the concentration of the odorant.
JTD Keywords: Gas sensor array, Biologically inspired system, Redundancy, Diversity, MOX sensors, Temperature modulation
Sarlabous, L., Torres, A., Fiz, J. A., Gea, J., Marti nez-Llorens, J. M., Morera, J., Jané, R., (2010). Interpretation of the approximate entropy using fixed tolerance values as a measure of amplitude variations in biomedical signals Engineering in Medicine and Biology Society (EMBC)
32nd Annual International Conference of the IEEE , IEEE (Buenos Aires, Argentina) , 5967-5970
A new method for the quantification of amplitude variations in biomedical signals through moving approximate entropy is presented. Unlike the usual method to calculate the approximate entropy (ApEn), in which the tolerance value (r) varies based on the standard deviation of each moving window, in this work ApEn has been computed using a fixed value of r. We called this method, moving approximate entropy with fixed tolerance values: ApEn/sub f/. The obtained results indicate that ApEn/sub f/ allows determining amplitude variations in biomedical data series. These amplitude variations are better determined when intermediate values of tolerance are used. The study performed in diaphragmatic mechanomyographic signals shows that the ApEn/sub f/ curve is more correlated with the respiratory effort than the standard RMS amplitude parameter. Furthermore, it has been observed that the ApEn/sub f/ parameter is less affected by the existence of impulsive, sinusoidal, constant and Gaussian noises in comparison with the RMS amplitude parameter.
JTD Keywords: Practical, Theoretical or Mathematical/ biomechanics, Entropy, Gaussian noise, Medical signal processing, Muscle, Random processes/ approximate entropy interpretation, Fixed tolerance values, Diaphragmatic mechanomyographic signals, ApEnf curve, Respiratory effort, Gaussian noises
Correa, L. S., Laciar, E., Mut, V., Giraldo, B. F., Torres, A., (2010). Multi-parameter analysis of ECG and Respiratory Flow signals to identify success of patients on weaning trials Engineering in Medicine and Biology Society (EMBC)
32nd Annual International Conference of the IEEE , IEEE (Buenos Aires, Argentina) -----, 6070-6073
Statistical analysis, power spectral density, and Lempel Ziv complexity, are used in a multi-parameter approach to analyze four temporal series obtained from the Electrocardiographic and Respiratory Flow signals of 126 patients on weaning trials. In which, 88 patients belong to successful group (SG), and 38 patients belong to failure group (FG), i.e. failed to maintain spontaneous breathing during trial. It was found that mean values of cardiac inter-beat and breath durations give higher values for SG than for FG; Kurtosis coefficient of the spectrum of the rapid shallow breathing index is higher for FG; also Lempel Ziv complexity mean values associated with the respiratory flow signal are bigger for FG. Patients were then classified with a pattern recognition neural network, obtaining 80% of correct classifications (81.6% for FG and 79.5% for SG).
JTD Keywords: Electrocardiography, Medical signal processing, Neural nets, Pattern recognition, Pneumodynamics, Signal classification, Statistical analysis, ECG, Kurtosis coefficient, Lempel Ziv complexity, Breath durations, Cardiac interbeat durations, Electrocardiography, Multiparameter analysis, Pattern recognition neural network, Power spectral density, Respiratory flow signals, Signal classification, Spontaneous breathing, Statistical analysis, Weaning trials
Leder, R. S., Schlotthauer, G., Penzel, T., Jané, R., (2010). The natural history of the sleep and respiratory engineering track at EMBC 1988 to 2010 Engineering in Medicine and Biology Society (EMBC)
32nd Annual International Conference of the IEEE , IEEE (Buenos Aires, Argentina) , 288-291
Sleep science and respiratory engineering as medical subspecialties and research areas grew up side-by-side with biomedical engineering. The formation of EMBS in the 1950's and the discovery of REM sleep in the 1950's led to parallel development and interaction of sleep and biomedical engineering in diagnostics and therapeutics.
JTD Keywords: Practical/ biomedical equipment, Biomedical measurement, Patient diagnosis, Patient monitoring, Patient treatment, Pneumodynamics, Sleep/ sleep engineering, Respiratory engineering, Automatic sleep analysis, Automatic sleep interpretation systems, Breathing, Biomedical, Engineering, Diagnostics, Therapeutics, REM sleep, Portable, Measurement, Ambulatory measurement, Monitoring
Arcentales, A., Giraldo, B. F., Caminal, P., Diaz, I., Benito, S., (2010). Spectral analysis of the RR series and the respiratory flow signal on patients in weaning process Engineering in Medicine and Biology Society (EMBC)
32nd Annual International Conference of the IEEE , IEEE (Buenos Aires, Argentina) , 2485-2488
A considerable number of patients in weaning process have problems to keep spontaneous breathing during the trial and after it. This study proposes to extract characteristic parameters of the RR series and respiratory flow signal according to the patients' condition in weaning test. Three groups of patients have been considered: 93 patients with successful trials (group S), 40 patients that failed to maintain spontaneous breathing (group F), and 21 patients who had successful weaning trials, but that had to be reintubated before 48 hours (group R). The characterization was performed using spectral analysis of the signals, through the power spectral density, cross power spectral density and Coherence method. The parameters were extracted on the three frequency bands (VLF, LF and HF), and the principal statistical differences between groups were obtained in bands of VLF and HF. The results show an accuracy of 76.9% in the classification of the groups S and F.
JTD Keywords: Biomedical measurement, Electrocardiography, Medical signal processing, Pneumodynamics, Spectral analysis, RR series, Coherence method, Cross power spectral density, Electrocardiography, Principal statistical differences, Respiratory flow signal, Spectral analysis, Spontaneous breathing, Weaning test
Tort, N., Salvador, J. P., Eritja, R., Poch, M., Martinez, E., Samitier, J., Marco, M. P., (2009). Fluorescence site-encoded DNA addressable hapten microarray for anabolic androgenic steroids
Trac-Trends in Analytical Chemistry , 28, (6), 718-728
We report a new strategy for immunochemical screening of small organic molecules based on the use of a hapten microarray. Using DNA-directed immobilization strategies, we have been able to convert a DNA chip into a hapten microarray by taking advantage of all the benefits of the structural and electrostatic homogeneous properties of DNA. The hapten microarray uses hapten-oligonucleotide probes instead of proteins, avoiding the limitations of preparing stochiometrically-defined protein-oligonucleotide bioconjugates. As proof of concept, we show here the development of a microarray for analysis of anabolic androgenic steroids. The microchip is able to detect several illegal substances with sufficient detectability to be used as a screening method, according to the regulations of the World Anti-Doping Agency for sport and the European Commision for food safety. The results that we show corroborate the universal possibilities of the DNA chip, and, in this case, they open the way to develop hapten microarrays for the immunochemical analysis of small organic molecules.
JTD Keywords: Anti-doping, DNA chip, DNA-directed immobilization (DDI), Fluorescence, Food safety, Hapten microarray, Immunochemical screening, Proof of concept, Small organic molecule, Steroid
Farre, R., Navajas, D., (2009). Quality control: A necessary, but sometimes overlooked, tool for improving respiratory medicine European Respiratory Journal 33, (4), 722-723
The importance of quality control in both general and respiratory medicine has increased in parallel with the complexity of healthcare provision. Only a few decades ago, the respiratory physician and/or scientist had a very limited number of diagnostic and therapeutic tools available and, moreover, medical practice was based almost exclusively on the personal interaction between doctor and patient. Consequently, at that time the quality of the respiratory healthcare depended entirely on the professional competence of the doctor. Although nowadays the relationship between physician and patient undoubtedly still lies at the heart of respiratory medical practice, the quality of the medical service received by the patient also depends on many other participants in a complex healthcare network: various medical specialists, lung function technicians, nurses, respiratory therapists, social workers and administrative staff. Accordingly, several quality control programmes are applied in order to avoid, or at least to reduce, errors in diagnosis, improper performance of procedures, errors in medication, and failure to supervise or monitor care or recognise complications associated with treatment
JTD Keywords: Airway pressure devices, Clinical-trial, Standardization, Spirometry, Lung, Home, Ventilators, Publication, Performance, Technology
Arteaga, O., Escudero, C., Oncins, G., El-Hachemic, Z., Llorens, J., Crusats, J., Canillas, A., Ribo, J. M., (2009). Reversible mechanical induction of optical activity in solutions of soft-matter nanophases
Chemistry - An Asian Journal , 4, (11), 1687-1696
Nanophases of J-aggregates of several achiral amphiphilic porphyrins, which have thin long acicular shapes (nanoribbons), show the immediate and reversible formation of a stationary mechano-chiral state in the solution by vortex stirring, as detected by their circular dichroic signals measured by 2-modulator generallized ellipsometry. The results suggest that when a macroscopic chiral force creates supramolecular chirality, it also creates an enantiomeric excess of screw distortions, which may be detected by their excitonic absorption. An explanation on the effect of the shear flow gradients is proposed on the basis of the orientation of the rotating particles in the vortex and the size, shape, and mechanical properties of the nanoparticles.
JTD Keywords: Chirality, Circular dichroism, Nanoparticles, Selfassembly, Supramolecular chemistry
Sellares, J., Acerbi, I., Loureiro, H., Dellaca, R. L., Ferrer, M., Torres, A., Navajas, D., Farre, R., (2009). Respiratory impedance during weaning from mechanical ventilation in a mixed population of critically ill patients
British Journal of Anaesthesia , 103, (6), 828-832
Worsening of respiratory mechanics during a spontaneous breathing trial (SBT) has been traditionally associated with weaning failure, although this finding is based on studies with chronic obstructive pulmonary disease patients only. The aim of our study was to assess the course of respiratory impedance non-invasively measured by forced oscillation technique (FOT) during a successful and failed SBT in a mixed population. Thirty-four weaning trials were reported in 29 consecutive mechanically ventilated patients with different causes of initiation of ventilation. During the SBT, the patient was breathing through a conventional T-piece connected to the tracheal tube. FOT (5 Hz, +/- 1 cm H2O, 30 s) was applied at 5, 10, 15, 20, 25, and 30 min. Respiratory resistance (Rrs) and reactance (Xrs) were computed from pressure and flow measurements. The frequency to tidal volume ratio f/V-t was obtained from the flow signal. At the end of the trial, patients were divided into two groups: SBT success and failure. Mixed model analysis showed no significant differences in Rrs and Xrs over the course of the SBT, or between the success (n=16) and the failure (n=18) groups. In contrast, f/V-t was significantly (P < 0.001) higher in the failure group. Worsening of respiratory impedance measured by FOT is not a common finding during a failed SBT in a typically heterogeneous intensive care unit population of mechanically ventilated patients.
JTD Keywords: Ventilation, High frequency oscillation, Ventilation, Mechanical, Ventilation, Respiratory impedance
Fonollosa, J., Halford, B., Fonseca, L., Santander, J., Udina, S., Moreno, M., Hildenbrand, J., Wöllenstein, J., Marco, S., (2009). Ethylene optical spectrometer for apple ripening monitoring in controlled atmosphere store-houses Sensors and Actuators B: Chemical 136, (2), 546-554
In today's store-houses the ripening of fruit is controlled by managing the ethylene concentration in the ambient atmosphere. Precise and continuous ethylene monitoring is very advantageous since low ethylene concentrations are produced by the fruit itself and are indicative of its ripeness, and on other occasions, ethylene is externally added when ripeness or degreening of the product must be promoted. In this work, a multichannel mid-infrared spectrometer for ethylene measurement is built and characterized. The instrument contains additional channels to reject potential cross-interferences like ammonia and ethanol. Additionally, these channels are useful for monitoring a potential malfunction of the cooling system and possible fouling of the fruit, respectively. The complete spectrometer contains a silicon-based macroporous infrared (IR) emitter, a miniaturized long path cell (white cell), a four-channel detector module, low-noise analog amplification and filtering, and a microcontroller-based lock-in amplifier. The new inner architecture of the detector module features a fourfold thermopile array with narrow band optical filters attached by flip-chip technology, and a Fresnel lens array attached on the lid of the package. Laboratory tests show that the system is able to distinguish between ammonia and ethylene, featuring a detection limit of 30 ppm and 160 ppm (95% confidence) for ethylene and ammonia, respectively. Field tests show that the spectrometer is suitable as an ethylene alarm to detect fruit ripening and prevent fruit to decline into senescence. Simulation results show that system selectivity could be improved by setting ammonia channel to another absorption wavelength.
JTD Keywords: IR spectrometer, Ethylene, Fruit storage, Fresnel lens, White cell, Lock-in amplifier
Morgenstern, C., Schwaibold, M., Randerath, W. J., Bolz, A., Jané, R., (2009). Assessment of changes in upper airway obstruction by automatic identification of inspiratory flow limitation during sleep IEEE Transactions on Biomedical Engineering 56, (8), 2006-2015
New techniques for automatic invasive and noninvasive identification of inspiratory flow limitation (IFL) are presented. Data were collected from 11 patients with full nocturnal polysomnography and gold-standard esophageal pressure (Pes) measurement. A total of 38,782 breaths were extracted and automatically analyzed. An exponential model is proposed to reproduce the relationship between Pes and airflow of an inspiration and achieve an objective assessment of changes in upper airway obstruction. The characterization performance of the model is appraised with three evaluation parameters: mean-squared error when estimating resistance at peak pressure, coefficient of determination, and assessment of IFL episodes. The model's results are compared to the two best-performing models in the literature. The obtained gold-standard IFL annotations were then employed to train, test, and validate a new noninvasive automatic IFL classification system. Discriminant analysis, support vector machines, and Adaboost algorithms were employed to objectively classify breaths noninvasively with features extracted from the time and frequency domains of the breaths' flowpatterns. The results indicated that the exponential model characterizes IFL and subtle relative changes in upper airway obstruction with the highest accuracy and objectivity. The new noninvasive automatic classification system also succeeded in identifying IFL episodes, achieving a sensitivity of 0.87 and a specificity of 0.85.
JTD Keywords: Esophageal pressure, Exponential model, Inspiratory flow limitation, Noninvasive, Classification, Upper airway obstruction
Puig, F., Gavara, N., Sunyer, R., Carreras, A., Farre, R., Navajas, D., (2009). Stiffening and contraction induced by dexamethasone in alveolar epithelial cells
Experimental Mechanics , 49, (1), 47-55
The structural integrity of the alveolar monolayer, which is compromised during lung inflammation, is determined by the balance between cell-cell and cell-matrix tethering forces and the centripetal forces owing to cell viscoelasticity and contraction. Dexamethasone is an anti-inflammatory glucocorticoid with protective effects in lung injury. To determine the effects of Dexamethasone on the stiffness and contractility of alveolar epithelial cells. Cell stiffness (G') and average traction exerted by the cell (T) were measured by magnetic twisting cytometry and by traction microscopy, respectively. A549 cells were treated 24 h with Dexamethasone (1 mu M) or vehicle (control). G' and T were measured before and 5 min after challenge with the inflammatory mediator Thrombin (0.5 U/ml). Changes induced by Dexamethasone in actin cytoskeleton polymerization were assessed by the fluorescent ratio between F-actin and G-actin obtained by staining cells with phalloidin and DNase I. Dexamethasone significantly increased G' and T by 56% (n = 11; p < 0.01) and by 80% (n = 17; p < 0.05), respectively. Dexamethasone also increased F/G-actin ratio from 2.68 +/- 0.07 to 2.96 +/- 0.09 (n = 10; p < 0.05). The relative increase in stiffness and contraction induced by Thrombin in control cells was significantly (p < 0.05) reduced by Dexamethasone treatment: from 190 to 98% in G' and from 318 to 105% in T. The cytoskeleton remodelling and the increase in cell stiffness and contraction induced by Dexamethasone could account for its protective effect in the alveolar epithelium when subjected to inflammatory challenge.
JTD Keywords: Cell mechanics, Cytoskeleton, Magnetic twisting cytometry, Traction microscopy, Respiratory diseases
Merolli, A., Rocchi, L., Catalano, F., Planell, J., Engel, E., Martinez, E., Sbernardori, M. C., Marceddu, S., Leali, P. T., (2009). In vivo regeneration of rat sciatic nerve in a double-halved stitch-less guide: a pilot-study
Microsurgery , 29, (4), 310-318
It is about 20 years that tubular nerve guides have been introduced into clinical practice as a reliable alternative to autograft, in gaps not-longer-than 20 mm, bringing the advantage of avoiding donor site sacrifice and morbidity. There are limitations in the application of tubular guides. First, tubular structure in itself makes surgical implantation difficult; second, stitch sutures required to secure the guide may represent a site of unfavorable fibroblastic reaction; third, maximum length and diameter of the guide correlate with the occurrence of a poorer central vascularization of regenerated nerve. We report on the in vivo testing of a new concept of nerve-guide (named NeuroBox) which is double-halved, not-degradable, rigid, and does not require any stitch to be held in place, employing acrylate glue instead. Five male Wistar rats had the new guide implanted in a 4-mm sciatic nerve defect; two guides incorporated a surface constituted of microtrenches aligned longitudinally. Further five rats had the 4-mm gap left without repair. Contralateral intact nerves were used as controls. After 2 months, nerve regeneration occurred in all animals treated by the NeuroBox; fine blood vessels were well represented. There was no regeneration in the un-treated animals. Even if the limited number of animals does not allow to draw definitive conclusions, some result can be highlighted: an easy surgical technique was associated with the box-shaped guide and acrylate glue was easily applied; an adequate intraneural vascularization was found concurrently with the regeneration of the nerve and no adverse fibroblastic proliferation was present.
JTD Keywords: Peripheral-nerve, Polyglycolic acid, Guidance cues, Collagen tube, Median nerve, Repair, Growth, Cyanoacrylate, Complications, Anastomosis
Colomer-Farrarons, J., Miribel-Catala, P. L., Samitier, J., Arundell, M., Rodriguez, I., (2009). Design of a miniaturized electrochemical instrument for in-situ O/sub 2/ monitoring Sensors and Signal Conditioning
VLSI Circuits and Systems IV , SPIE (Desdren, Germany) 7363, 73630A
The authors are working toward the design of a device for the detection of oxygen, following a discrete and an integrated instrumentation implementation. The discrete electronics are also used for preliminary analysis, to confirm the validity of the conception of system, and its set-up would be used in the characterization of the integrated device, waiting for the chip fabrication. This paper presents the design of a small and portable potentiostat integrated with electrodes, which is cheap and miniaturized, which can be applied for on-site measurements for the simultaneous detection of O/sub 2/ and temperature in water systems. As a first approach a discrete PCB has been designed based on commercial discrete electronics and specific oxygen sensors. Dissolved oxygen concentration (DO) is an important index of water quality and the ability to measure the oxygen concentration and temperature at different positions and depths would be an important attribute to environmental analysis. Especially, the objective is that the sensor and the electronics can be integrated in a single encapsulated device able to be submerged in environmental water systems and be able to make multiple measurements. For our proposed application a small and portable device is developed, where electronics and sensors are miniaturized and placed in close proximity to each other. This system would be based on the sensors and electronics, forming one module, and connected to a portable notebook to save and analyze the measurements on-line. The key electronics is defined by the potentiostat amplifier, used to fix the voltage between the working (WE) and reference (RE) electrodes following an input voltage (Vin). Vin is a triangular signal, programmed by a LabView/sup c / interface, which is also used to represent the CV transfers. To obtain a smaller and compact solution the potentiostat amplifier has also been integrated defining a full custom ASIC amplifier, which is in progress, looking for a point-of-care device. These circuits have been designed with a 0.13 mu m technology from ST Microelectronics through the CMP-TIMA service.
JTD Keywords: Amplifiers, Application specific integrated circuits, Chemical sensors, Electrodes, Portable instruments, Temperature measurement, Water sources
Padilla, M., Pereral, A., Montoliu, I., Chaudry, A., Persaud, K., Marco, S., (2009). Improving drift correction by double projection preprocessing in gas sensor arrays Olfaction Electronic Nose: Proceedings of the 13th International Symposium on Olfaction and Electronic Nose
13th International Symposium on Olfaction and the Electronic Nose (ed. Pardo, M., Sberveglieri, G.), Amer Inst Physics (Brescia, Italy) 1137, 101-104
It is well known that gas chemical sensors are strongly affected by drift. Drift consist on changes in sensors responses along the time, which make that initial statistical models for gas or odor recognition become useless after a period of time of about weeks. Gas sensor arrays based instruments periodically need calibrations that are expensive and laborious. Many different statistical methods have been proposed to extend time between recalibrations. In this work, a simple preprocessing technique based on a double projection is proposed as a prior step to a posterior drift correction algorithm (in this particular case, Direct Orthogonal Signal Correction). This method highly improves the time stability of data in relation with the one obtained by using only such drift correction method. The performance of this technique will be evaluated on a dataset composed by measurements of three analytes by a polymer sensor array along ten months.
JTD Keywords: Drift, Direct orthogonal signal correction
Hernansanz, A., Amat, J., Casals, A., (2009). Optimization criterion for safety task transfer in cooperative robotics
14th International Conference on Advanced Robotics (ICAR) , IEEE (Munich, Germany) , 254-259
This paper presents a strategy for a cooperative multirobot system, constituting a virtual robot. The virtual robot is composed of a set of robotic arms acting as only one, transferring the execution of a teleoperated task from one to another when necessary. To decide which of the robots is the most suitable to execute the task at every instant, a multiparametric decision function has been defined. This function is based on a set of intrinsic and extrinsic evaluation indexes of the robot. Since the internal operation of the virtual robot must be transparent to the user, a control architecture has been developed.
JTD Keywords: Control engineering computing, Manipulators, Multi-robot systems, Optimsation, Telerobotics, Virtual reality
Guaus, E., Torrent-Burgues, J., Zine, N., Errachid, A., (2009). Glassy carbon electrode modified with a langmuir-blodgett film of a thiomacrocyclic ionophore for Cu(II) recognition Sensor Letters
6th Maghreb-Europe Meeting on Materials and Their Applications for Devices and Physical, Chemical and Biological Sensors , AMER SCIENTIFIC PUBLISHERS (Rabat, Morocco) 7, (5), 1006-1011
Nanometric films of a thiomacrocyclic ionophore, 4-phenyl-4-sulfide-11(1- oxodecyl)-1,7-dithia-11-aza-4-phosphacyclotetradecane (ThM), have been deposited on the surface of a Glassy Carbon Electrode (GCE) by the Langmuir-Blodgett (LB) technique. The films have been characterised by using AFM. The influence of these modified electrodes (GCE-ThM) on the reduction of Cu(II) ions has been investigated by using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS), and its sensor response has been checked. The CV and EIS responses of LB films on GCE indicate that these ThM films are sensitive to Cu(II) ions. The analysis by EIS of the interference of some other cations, as Mg(II) and Co(II), shows that LB films of ThM can be used for specific Cu(II) sensing applications.
JTD Keywords: Cu(II) sensor, Cyclic voltammetry, Electrochemical impedance spectroscopy, Langmuir-blodgett films
Lacroix, D., (2009). Biomechanical aspects of bone repair
Bone repair biomaterials (ed. Planell, J. A., Lacroix, D., Best, S., Merolli, A.), Woodhead (Cambridge, UK)
A fundamental aspect of the rapidly expanding medical care sector, bone repair continues to benefit from emerging technological developments. This text provides researchers and students with a comprehensive review of the materials science and engineering principles behind these developments. The first part reviews the fundamentals of bone repair and regeneration. Further chapters discuss the science and properties of biomaterials used in bone repair, including both metals and biocomposites. Final chapters analyze device considerations such as implant lifetime and failure, and discuss potential applications, as well as the ethical issues that continually confront researchers and clinicians.
JTD Keywords: Bone composition and structure, Biomechanical properties of bone, Bone damage and repair
Planell, J. A., Navarro, M., (2009). Challenges in bone repair
Bone repair biomaterials (ed. Planell, J. A., Lacroix, D., Best, S., Merolli, A.), Woodhead (Cambridge, UK) , 3-24
Almendros, I., Carreras, A., Ramirez, J., Montserrat, J. M., Navajas, D., Farre, R., (2008). Upper airway collapse and reopening induce inflammation in a sleep apnoea model European Respiratory Journal 32, (2), 399-404
The upper airway of obstructive sleep apnoea patients is subjected to recurrent negative pressure swings promoting its collapse and reopening. The aim of the present study was to ascertain whether this mechanical stress induces upper airway inflammation in a rat model. The upper airway of Sprague-Dawley rats was subjected to a periodic pattern of recurrent negative (-40 cmH2O, 1 s) and positive (4 cmH2O, 2 s) pressures inducing collapse and reopening for 5 h. Rats that were instrumented but not subjected to negative pressure swings were used as controls. The gene expression of the pro-inflammatory biomarkers macrophage inflammatory protein (MIP)-2, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and P-selectin in the soft palate and larynx tissues was assessed by real-time PCR. A marked overexpression of MIP-2, TNF-alpha, IL-1beta and P-selectin (approximately 40-, 24-, 47- and 7-fold greater than controls, respectively) was observed in the larynx tissue; similar results were found in the soft palate tissue (approximately 14-, 7-, 35- and 11-fold greater than controls, respectively). Recurrent upper airway collapse and reopening mimicking those experienced by obstructive sleep apnoea patients triggered an early local inflammatory process. These results could explain the inflammation observed in the upper airway of obstructive sleep apnoea patients.
JTD Keywords: Airway collapse, Airway reopening, Inflammation, Negative pressure, Obstructive sleep apnoea, Upper airway
Roca, Ignasi, Torrents, Eduard, Sahlin, Margareta, Gibert, Isidre, Sjoberg, Britt-Marie, (2008). NrdI essentiality for class Ib ribonucleotide reduction in streptococcus pyogenes
Journal of Bacteriology , 190, (14), 4849-4858
The Streptococcus pyogenes genome harbors two clusters of class Ib ribonucleotide reductase genes, nrdHEF and nrdF*I*E*, and a second stand-alone nrdI gene, designated nrdI2. We show that both clusters are expressed simultaneously as two independent operons. The NrdEF enzyme is functionally active in vitro, while the NrdE*F* enzyme is not. The NrdF* protein lacks three of the six highly conserved iron-liganding side chains and cannot form a dinuclear iron site or a tyrosyl radical. In vivo, on the other hand, both operons are functional in heterologous complementation in Escherichia coli. The nrdF*I*E* operon requires the presence of the nrdI* gene, and the nrdHEF operon gained activity upon cotranscription of the heterologous nrdI gene from Streptococcus pneumoniae, while neither nrdI* nor nrdI2 from S. pyogenes rendered it active. Our results highlight the essential role of the flavodoxin NrdI protein in vivo, and we suggest that it is needed to reduce met-NrdF, thereby enabling the spontaneous reformation of the tyrosyl radical. The NrdI* flavodoxin may play a more direct role in ribonucleotide reduction by the NrdF*I*E* system. We discuss the possibility that the nrdF*I*E* operon has been horizontally transferred to S. pyogenes from Mycoplasma spp.
JTD Keywords: Group-a streptococcus, Bacillus-subtilis genes, Escherichia-coli, Corynebacterium-ammoniagenes, Mycobacterium-tuberculosis, Expression analysis, Genome sequence, Small-subunit, Salmonella-typhimurium, Iron center
Guaus, E., Errachid, A., Torrent-Burgues, J., (2008). Voltammetric response of a glassy carbon electrode modified by a Langmuir-Blodgett film of a thiomacrocyclic compound
Journal of Electroanalytical Chemistry , 614, (1-2), 73-82
A Langmuir-Blodgett (LB) film of a thiomacrocyclic (ThM) compound was deposited on the surface of a glassy carbon electrode (GCE) sheet, from a subphase containing Cu(II) ions. The study of the voltammetric response of this modified GCE when the ThM was bonded to Cu2+, showed that the films had the behaviour of confined species of an electrode surface, and that the current density of the voltammograms increased with the number of LB layers deposited. On the other hand, a LB film of the ThM compound was deposited on the surface of a GCE sheet from a subphase of pure water. When the voltammetric response of the GCE-ThM electrode was studied in a Cu2+-SO42- solution, it was found that a membrane model applies to describe the effect of the LB film on the GCE surface.
JTD Keywords: Modified electrodes, Langmuir-Blodgett films, Cyclic voltammetry, Permeation at LB films, Membrane model of a thin film
Farre, R., Montserrat, J. M., Navajas, D., (2008). Assessment of upper airway mechanics during sleep
Respiratory Physiology & Neurobiology , 163, (1-3), 74-81
Obstructive sleep apnea, which is the most prevalent sleep breathing disorder, is characterized by recurrent episodes of upper airway collapse and reopening. However, the mechanical properties of the upper airway are not directly measured in routine polysomnography because only qualitative sensors (thermistors for flow and thoraco-abdominal bands for pressure) are used. This review focuses on two techniques that quantify upper airway obstruction during sleep. A Starling model of collapsible conduit allows us to interpret the mechanics of the upper airway by means of two parameters: the critical pressure (Pcrit) and the upstream resistance (Rup). A simple technique to measure Pcrit and Rup involves the application of different levels of continuous positive airway pressure (CPAP) during sleep. The forced oscillation technique is another non-invasive procedure for quantifying upper airway impedance during the breathing cycle in sleep studies. The latest developments in these two methods allow them to be easily applied on a routine basis in order to more fully characterize upper airway mechanics in patients with sleep breathing disorders.
JTD Keywords: Obstructive sleep apnea, Upper airway, Airway resistance, Critical pressure, Respiratory impedance
Manara, S., Paolucci, F., Palazzo, B., Marcaccio, M., Foresti, E., Tosi, G., Sabbatini, S., Sabatino, P., Altankov, G., Roveri, N., (2008). Electrochemically-assisted deposition of biomimetic hydroxyapatite-collagen coatings on titanium plate Inorganica Chimica Acta 361, (6), 1634-1645
A biomimetic bone-like composite, made of self-assembled collagen fibrils and carbonate hydroxyapatite nanocrystals, has been performed by an electrochemically-assisted deposition on titanium plate. The electrolytic processes have been carried out using a single type I collagen molecules suspension in a diluted Ca(NO3)(2) and NH4H2PO4 solution at room temperature and applying a constant current for different periods of time. Using the same electrochemical conditions, carbonate hydroxyapatite nanocrystals or reconstituted collagen. brils coatings were obtained. The reconstituted collagen. brils, hydroxyapatite nanocrystals and collagen fibrils/apatite nanocrystals coatings have been characterized chemically, structurally and morphologically, as well as for their ability to bind fibronectin (FN). Fourier Transform Infrared microscopy has been used to map the topographic distribution of the coating components at different times of electrochemical deposition, allowing to single out the individual deposition steps. Moreover, roughness of Ti plate has been found to affect appreciably the nucleation region of the inorganic nanocrystals. Laser scanning confocal microscopy has been used to characterize the FN adsorption pattern on a synthetic biomimetic apatitic phase, which exhibits a higher affinity when it is inter-grown with the collagen fibrils. The results offer auspicious applications in the preparation of medical devices such as biomimetic bone-like composite-coated metallic implants.
JTD Keywords: Hydroxyapatite-collagen coating, Electrochemically-assisted deposition, Micro-imaging FTIR spectroscopy, Laser scanning confocal microscopy, Biomimetic crystal growth, Fibronectin binding
Morgenstern, C., Jané, R., Schwaibold, M., Randerath, W., (2008). Automatic classification of inspiratory flow limitation assessed non-invasively during sleep IEEE Engineering in Medicine and Biology Society Conference Proceedings
30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (ed. IEEE), IEEE (Vancouver, Canada) 1-8, 1132-1135
Detection of inspiratory flow limitation (IFL) is being recognized of increasing importance in order to diagnose pathologies related to sleep disordered breathing. Currently, IFL is usually identified with the help of invasive esophageal pressure measurement, still considered the gold-standard reference to assess respiratory effort. But the invasiveness of esophageal pressure measurement and its impact on sleep discourages its use in clinical routine. In this study, a new non-invasive automatic system is proposed for objective IFL classification. First, an automatic annotation system for IFL based on pressure/flow relationship was developed. Then, classifiers (Support Vector Machines and adaboost classifiers) were trained with these gold-standard references in order to objectively classify breaths non-invasively, solely based on the breaths' flow contours. The new non-invasive automatic classification system seems to be promising, as it achieved a sensitivity of 0.92 and a specificity of 0.89, outperforming prior classification results obtained by human experts.
JTD Keywords: Upper airway-resistance
Solà, J., Jané, R., Fiz, J. A., Morera, J., (2008). Formant frequencies of normal breath sounds of snorers may indicate the risk of obstructive sleep apnea syndrome IEEE Engineering in Medicine and Biology Society Conference Proceedings
30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (ed. IEEE), IEEE (Vancouver, Canada) 1-8, 3500-3503
Several differences between the airway of normal subjects and those with OSAS are well known. The characteristics of the upper airway may be indirectly studied through the formant frequencies of breathing sounds. In this work we analyze the formants of inspiration and exhalation sounds in snoring subjects with and without OSAS. Formant frequencies of inspiration and exhalation appear in the same bands as snores. Formant F1 is significantly lower in inspiration episodes of OSAS patients (p=0.008) with a decreasing tendency as the AHI increases (r=0.705). In addition, this formant has a significantly higher variability SF1 in pathological subjects, for both inspiration (p=0.022) and exhalation (p=0.038) episodes, as was previously found in snores. A higher variability of formant frequencies seems to be an indicator of the presence of OSAS. The proposed technique could allow the identification of OSAS patients from normal breathing alone.
JTD Keywords: Upper airway
Orini, Michele, Giraldo, Beatriz F., Bailon, Raquel, Vallverdu, Montserrat, Mainardi, Luca, Benito, Salvador, Diaz, Ivan, Caminal, Pere, (2008). Time-frequency analysis of cardiac and respiratory parameters for the prediction of ventilator weaning IEEE Engineering in Medicine and Biology Society Conference Proceedings
30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (ed. IEEE), IEEE (Vancouver, Canada) 1-8, 2793-2796
Mechanical ventilators are used to provide life support in patients with respiratory failure. Assessing autonomic control during the ventilator weaning provides information about physiopathological imbalances. Autonomic parameters can be derived and used to predict success in discontinuing from the mechanical support. Time-frequency analysis is used to derive cardiac and respiratory parameters, as well as their evolution in time, during ventilator weaning in 130 patients. Statistically significant differences have been observed in autonomic parameters between patients who are considered ready for spontaneous breathing and patients who are not. A classification based on respiratory frequency, heart rate and heart rate variability spectral components has been proposed and has been able to correctly classify more than 80% of the cases.
JTD Keywords: Automatic Data Processing, Databases, Factual, Electrocardiography, Humans, Models, Statistical, Respiration, Respiration, Artificial, Respiratory Insufficiency, Respiratory Mechanics, Respiratory Muscles, Signal Processing, Computer-Assisted, Time Factors, Ventilator Weaning, Ventilators, Mechanical, Work of Breathing
Torrent-Burgues, J., Oncins, G., Sanz, F., (2008). Study of mixed Langmuir and Langmuir-Blodgett films of dissimilar components by AFM and force spectroscopy Colloids and Surfaces a-Physicochemical and Engineering Aspects
12th International Conference on Organized Molecular Films , Elsevier Science (Krakow, Poland) 321, (1-3), 70-75
In this study the structure of mixed Langmuir-Blodgett (LB) monolayers has been investigated using atomic force microscopy, lateral force microscopy and force spectroscopy, as well as the characteristics of the Langmuir monolayers by surface pressure-area isotherms and Brewster angle microscopy. Mixed films were of dissimilar compounds, a fatty acid such as arachidic acid and a macrocyclic compound. The mixture forms separated phases, but some degree of partial miscibility occurs, with domains at the micro-scale that have different nanomechanical and nanotribological properties. LB films transferred at the same surface pressure show different characteristics depending on the composition. The higher domains correspond to arachidic acid and some of these domains show the presence of two phases, which have been identified as phases with discrete molecular tilting angles.
JTD Keywords: Mixed monolayers, Pressure-area isotherm, Langmuir-Blodgett, AFM, Force spectroscopy
Farre, R., Nacher, M., Serrano-Mollar, A., Galdiz, J. B., Alvarez, F. J., Navajas, D., Montserrat, J. M., (2007). Rat model of chronic recurrent airway obstructions to study the sleep apnea syndrome
Sleep , 30, (7), 930-933
Study Objectives: To implement a chronic rat model of recurrent airway obstructions to study the obstructive sleep apnea (OSA) syndrome. Design: Prospective controlled animal study. Setting: University laboratory. Patients or Participants: 24 male Sprague-Dawley rats (250-300 g). Interventions: The rats were placed in a setup consisting of a body chamber and a head chamber separated by a neck collar specially designed to apply recurrent airway obstructions with OSA patterns. Rats in the Obstruction group (n=8) were subjected to 5-s obstructions at a rate of 60 per hour, 6 h/day during 4 weeks. Sham rats (n=8) were placed in the setup but no obstructions were applied. Naive rats (n=8) were subjected to no intervention. Measurements and Results: Breathing flow, pressure, CO2 air concentration, and SpO(2) showed that the model mimicked OSA respiratory events (obstructive apneas, increased respiratory efforts, and oxygen saturation dips). Animal stress, assessed by body weight and plasma corticosterone, was not significantly different across Obstruction and Sham groups. This supports the concept that this novel model does not introduce a significant burden of stress in the rat after acclimatization to the chamber. Thromboxane-B2/6-keto-Prostaglandin-F1a ratio in plasma, which is an index of vasoconstriction, was significantly increased in the rats subjected to obstructions. Conclusions: The designed animal model of chronic recurrent airway obstructions is feasible and potentially useful to study the mechanisms involved in the cardiovascular consequences of OSA.
JTD Keywords: Obstructive sleep apnea, Animal model, Airway obstruction
Mills, C. A., Pla, M., Martin, C., Lee, M., Kuphal, M., Sisquella, X., Martinez, E., Errachid, A., Samitier, J., (2007). Structured thin organic active layers and their use in electrochemical biosensors
Measurement & Control , 40, (3), 88-91
Díez-Pérez, Ismael, Guell, Aleix Garcia, Sanz, Fausto, Gorostiza, Pau, (2006). Conductance maps by electrochemical tunneling spectroscopy to fingerprint the electrode electronic structure
Analytical Chemistry , 78, (20), 7325-7329
We describe a methodology to perform reliable tunneling spectroscopy in electrochemical media. Sequential in situ tunneling spectra are recorded while the electrochemical potential of the electrode is scanned. Spectroscopic data are presented as conductance maps or conductograms that show the in situ electronic structure of an electrode surface while it undergoes an electrochemical reaction. The conductance map or conductogram represents the redox fingerprint of an electrode/liquid interface in a specific medium and can serve to predict its electrochemical behavior in a quantitative energy scale. The methodology is validated studying the reversible oxidation and passivity of an iron electrode in borate buffer, and we describe the main quantitative information that can be extracted concerning the semiconducting properties of the Fe passive film. This methodology is useful to study heterogeneous catalysis, electrochemical sensing and bioelectronic systems.
JTD Keywords: Passive film, Oxide-film, Stainless-steel, Iron, Microscope, Surfaces, STM, Probes