Publications

Treating bacterial biofilms remains a major clinical challenge, particularly in uropathogenic infections where the dense extracellular matrix impedes antibiotic access and protects tolerant bacterial populations. In this work, we explored a nanomaterial-based strategy to improve antibiotic responsiveness by combining iron oxide nanoparticles (IONPs) with pulsed laser irradiation to induce vapor nanobubble (VNB)-mediated disruption of a mature flow-grown uropathogenic E. coli CFT073 biofilm. We tested three nanoparticle sizes (70 nm, 130 nm, and 500 nm) and identified IONP500 as the most effective formulation for generating VNBs upon irradiation with 532 nm nanosecond laser pulses, with a VNB threshold of 0.56 J/cm2 per pulse. In the mature biofilm model, the combined IONP500 + ciprofloxacin + laser treatment significantly enhanced antibiotic activity compared with ciprofloxacin alone, increasing dead biomass from approximately 16% to 23%, corresponding to a 39-45% relative increase, as quantified by COMSTAT analysis and one-way ANOVA with Tukey's post-hoc test. The combined treatment also reduced total biofilm biomass and increased biofilm porosity by 55.8% compared with ciprofloxacin alone, supporting a mechanism based on VNB-mediated matrix disruption and improved antibiotic access. Overall, these results support the use of photothermally active, biocompatible IONPs as a promising complementary strategy to enhance the efficacy of conventional antibiotics against persistent biofilm-associated infections.

JTD Keywords: Cells, Ciprofloxacin potentiation, Iron oxide nanoparticles, Laser, Nanoparticles, Photoporation, Photothermal biofilm disruption, Prostate, Resistance, Transurethral resection, Uropathogenic biofilms, Vapor nanobubbles, Vaporization

Wound infections affect 2% of the global population, causing chronic wounds and healthcare burdens as conventional antibiotics increasingly fail against biofilms. Consequently, attention is shifting toward advanced dressings that simultaneously prevent infection and support tissue regeneration. Among these, fibrous drug delivery systems have emerged as promising platforms for localized and controlled therapeutic delivery. Beyond platform geometry, physicochemical properties of the polymers are paramount in establishing biocompatibility, tunable degradation kinetics, and adequate mechanical integrity. PLGA and PLA/PCL-based nanofibrous platforms exhibit these favorable characteristics, even though they are still limited by issues such as limited control over release kinetics and potential instability of bioactive agents during fabrication. To address the limitations, hybrid platforms combining electrospun nanofibers with drug-loaded nanoparticles have been developed to provide structural integrity and secondary drug reservoirs for sustained release. Here, we developed a dualcarrier hybrid delivery platform to overcome burst release kinetics and achieve sustained local therapeutic levels by integrating microfluidically synthetized nanoparticles with electrospun nanofibrous matrices. To systematically elucidate the role of scaffold structure on the in-vitro performances, two delivery strategies were investigated: (i) direct entrapment of therapeutics within electrospun PLGA and PLA/PCL fibers, and (ii) surface coating of electrospun mats with PLGA nanoparticles. This study uses these approaches to encapsulate a hydrophobic agent, curcumin (CURC), a natural antimicrobial agent with limited solubility, and hydrophilic peptide, bovine lactoferricin (bLFC), which requires protection from enzymatic degradation. The use of these naturally derived compounds offers a promising non-antibiotic strategy to mitigate antibiotic resistance while promoting wound healing.

JTD Keywords: Antimicrobial agents, Biofilms, Curcumin, Dissolution profile, Dressings, Electrospinning, Hybrid scaffolds, Mechanisms, Microfluidics, Penetrant diffusion, Release, Solute, Swellable polymers, Wound infection

Hyperpolarized (HP) 13C nuclear magnetic resonance (NMR) spectroscopy enables real-time observation of metabolic fluxes but is typically limited to single-shot measurements due to complex preparation procedures and low experimental throughput. Here, we established a rapid and experimentally accessible workflow for temporally controlled HP measurements in living cells. Using SABRE-SHEATH at 0.4 & micro;T, we achieved 7.7% +/- 0.2% 13C polarization of 50 mM [1-13C]pyruvate within 60 s. Simple 1:50 dilution with phosphate-buffered D2O yielded cell-compatible solutions that retained 5.3% +/- 0.4% polarization of 1.3 mM pyruvate without multi-step purification. Combined with a simplified agarose bead immobilization approach, this enabled four injections of HP pyruvate into the same HeLa cell population within 7 min. Under rapid (approximate to 2 min) reinjection intervals, the pyruvate-to-lactate conversion progressively declined, whereas stable metabolic conversion was maintained at 20 min intervals with intermittent cell medium perfusion. These findings demonstrate that rapid repeated substrate delivery can transiently exhaust cellular metabolic conversion capacity. This experimentally accessible operating mode enables the study of short-term metabolic dynamics that remain obscured in conventional single-shot HP-NMR or long timescale thermally polarized NMR measurements.

JTD Keywords: Bioreactor, Carbon-13, Culture, Glucose, Hyperpolarization, Metabolism, Para-hydrogen, Parahydrogen, Polarization, Pyruvate, Sabre

Blinding diseases due to the degeneration of photoreceptors (PhRs), such as geographic atrophy (GA) secondary to dry age-related macular degeneration and retinitis pigmentosa (RP), leave the rest of the retinal circuitry largely intact, albeit unable to respond to light. Gene therapy has been able to revert PhR degeneration, but it can be applied only to a rare mutation affecting a small subset of RP patients. Alternatively, implanted electronic retinal prostheses aim at a larger population by electrically stimulating surviving neurons. However, the treatment is invasive and costly and provides limited resolution. Photopharmacology can develop photoswitchable small molecules to restore vision impairment by conferring light sensitivity to ion channels that are widely expressed in the remaining inner retinal neurons, and a first-in-human clinical trial is ongoing. Here, we have developed novel photoswitchable small-molecule ligands of metabotropic glutamate 6 (mGlu6) receptors, which are located exclusively at the dendrites of ON bipolar cells (postsynaptic to PhRs) and can leverage a privileged position to mimic physiological signals in the remnant retinal circuit. These photoswitchable ligands (prosthe6) thus act as "molecular prostheses" that can restore the light input to the retina via upstream-targeted control of the circuit after PhR degeneration. Prosthe6 compounds are allosteric, drug-like, water-soluble, and display outstanding in vitro properties including full efficacy, nanomolar potency, fast deactivation in ambient white light, and fast reactivation in the dark. In vivo experiments show that they readily recover the saccadic eye movements of blinded zebrafish larvae and restore the innate light-avoidance behavior in the mouse models of blindness (GA and RP). These effects are mediated by mGlu6 receptors in vivo. In addition, at least two compounds (prosthe6-12 and -15) can restore sight by topical administration and display promising safety properties to become potential drug candidates for sight restoration in patients with degenerative blinding diseases.

JTD Keywords: Allosteric modulators, Bipolar cells, Blind mice, Ectopic expression, Gene-therapy, Human rod, Protein-coupled receptors, Restores visual responses, Retinal degeneration, Zebrafish models

Doping of calcium phosphates (CaPs) with bioinorganic ions is a widely used strategy to enhance their biological performance in bone regeneration. However, conventional methods for ionic incorporation in CaP scaffolds often require high-temperature treatments or involve multiple complex steps. Here, we present two simple strategies to dope 3D-printed CaP scaffolds via incorporation of ions into the apatitic phase during the hydrolysis of alpha-tricalcium phosphate (alpha-TCP) to calcium deficient hydroxyapatite (CDHA). In the first strategy, ions were incorporated directly into the printing ink, whereas in the second, undoped robocasted scaffolds were immersed in ionic solutions, allowing ion incorporation into precipitated CDHA during phase transformation. We investigated several ions, including strontium (Sr2+), magnesium (Mg2+), silicon (SiO44- ) and gallium (Ga3+). Sr2+ and Ga3+ were successfully incorporated into the scaffolds, either by direct ink doping (Sr2+) or by soaking in ionic solutions (Sr2+ and Ga3+). Direct incorporation of Sr2+ in the ink resulted in a higher ion loading and release, enhancing bone formation and bone quality, as evidenced by increased mineral-to-matrix ratio and Young's modulus, as well as osteoinductive properties relative to non-doped scaffolds. Furthermore, we demonstrated for the first time the osteoinductive capacity of Ga3+ in an ectopic in vivo model.

JTD Keywords: 3d printing, Apatite, Biomimetic hydroxyapatite, Bone regeneration, Calcium phosphates, Calcium-phosphate cement, Differentiation, Ion doping, Magnesium-deficiency, Microporosity, Nanocrystals, Osteoinduction, Scaffold, Silicon, Substituted hydroxyapatite, Vitro

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

JTD Keywords: Allogeneic, Gmp, Induced-msc

Despite advances in bone graft design and surgical techniques, bacterial infection remains a major cause of graft failure, exacerbated by the global rise in antimicrobial resistance. This has intensified the pursuit of antibioticfree strategies to prevent bacterial colonization. Among these, antibacterial surface nanotopographies have emerged as promising tools, leveraging nanoscale geometries to physically disrupt bacteria upon contact. In this study, we engineered the surface of a calcium phosphate bone graft to confer antimicrobial functionality through a dual approach: the creation of high-aspect-ratio nanotopographies and ionic doping with fluoride. Through controlled hydrolysis of alpha-tricalcium phosphate by biomimetic and hydrothermal treatments, we generated calcium deficient hydroxyapatite nanoneedle structures whose morphology and biofunctionality were tuned via fluoride incorporation. XRD and Raman spectroscopy confirmed the formation of hydroxy-fluorapatite, with phase composition and surface morphology dependent on fluoride concentration and processing parameters. Fluoride doping significantly altered nanoneedle dimensions and spacing and enhanced bactericidal activity, particularly against P. aeruginosa, and to a lesser extent S. aureus. Notably, fluoride-doping alone showed no antibacterial effects; however, when combined with nanotopography, a synergistic increase in efficacy was observed. Importantly, the antimicrobial surfaces supported the proliferation and osteogenic differentiation of SaOS-2 cells. Co-culture assays modeling pre- and post-implantation infection scenarios demonstrated robust cell adhesion and markedly reduced bacterial colonization. In conclusion, our findings present a multifunctional, synthetic bone graft with both physical and chemical antibacterial properties, offering a promising strategy to mitigate infection risks while supporting osteointegration.

JTD Keywords: Antibacterial nanotopography, Bactericidal surfaces, Biomaterials, Bone regeneration, Calcium phosphate, Cements, Coatings, Cytokines, Fluoride, Hydroxyapatite, Infections, Magnesium, Pseudomonas-aeruginosa, Setting reaction

The cell nucleus is continuously exposed to external signals, of both chemical and mechanical nature. To ensure proper cellular response, cells need to regulate the transmission, timing and duration of these signals. Although such timescale regulation is well described for chemical signals, whether and how it applies to mechanical signals reaching the nucleus is still not fully understood. Here we demonstrate that the formation of fibrillar adhesions locks the nucleus in a mechanically deformed conformation, setting the mechano-response timescale to that of fibrillar adhesion remodelling (similar to 1 h). This process encompasses both mechanical deformation and associated mechanotransduction (such as via YAP), in response to both increased and decreased mechanical stimulation. The underlying mechanism is the anchoring of the vimentin cytoskeleton to fibrillar adhesions and the extracellular matrix through plectin 1f, which maintains nuclear deformation. Our results reveal a mechanism to regulate the timescale of mechanical adaptation, effectively setting a low-pass filter to mechanotransduction.

JTD Keywords: Cells, F1, Forces, Mechanotransduction, Memory, Protein, Shape, Stiffness, Streptococcus-pyogenes, Translocation

Despite their extensive use, the therapeutic potential of nonsteroidal anti-inflammatory drugs (NSAIDs) remains significantly constrained by adverse side effects. This limitation primarily arises from insufficient selectivity, as current NSAIDs inhibit not only the inducible cyclooxygenase-2 (COX-2) isoform at sites of inflammation but also constitutive COX-2 in healthy tissues and, frequently, cyclooxygenase-1. To address this challenge, we developed photoswitchable NSAIDs that combine COX-2 selectivity with light-controlled activity to enable spatiotemporal confinement of the therapeutic effect at inflamed tissues. Following computational design and screening of a library of azoaromatic derivatives of celecoxib-the most widely used COX-2 selective NSAID-three photoswitchable analogues were synthesized, which exhibited reversible and efficient trans-cis photoconversion. Light-controlled and selective COX-2 inhibition was demonstrated for these compounds in vitro, reaching up to 5-fold potency enhancement in macrophage assays upon photoisomerization from the initial, dark-adapted trans isomer to the cis state. The best candidate displayed in vivo efficacy in a zebrafish model of acute inflammation, where administration of the photoinduced cis form reduced leukocyte recruitment at the wound site. These findings position photoswitchable NSAIDs as a promising alternative to conventional drugs for treating inflammation and related conditions, including cancer.

JTD Keywords: Cancer, Cox-2, Cyclooxygenase-2, Drugs, In-vivo, Inflammation, Risk, Vitro

Background/Objectives: The question addressed in the current work is to develop a simulation of a pharmaceutical process (DNA encapsulation within lipid nanoparticles using a microfluidic micromixer) which will be of utility to the end users (laboratory-scale formulation development). The simulation and the microfluidic approach also address sustainability issues, such as reducing the environmental impact of the process itself, and reducing the need for physical testing. The paper details the implementation and validation, taking into account key performance indicators and control parameters. Methods: The main method applied for simulation development is a novel multi-agent approach to incorporate stochastic probabilistic behavior, combined with theoretical definitions from the process experts and relevant literature, and data/results from laboratory-scale experiments with different parameter configurations. Results: The simulation was implemented as a representation of the real physical process, reproducing the relationships between process parameters (flow rates) and experimental key performance indicators (capsule diameter, poly dispersion index, encapsulation efficiency). The simulation results demonstrated a general agreement with the empirical results and provided useful predictive insights for the laboratory experiments. Conclusions: The simulation has potential as a support tool for laboratory experiments to reduce physical testing and indicate the most promising configurations on which to focus, with potential savings in time, resources and other costs.

JTD Keywords: Calibration, Encapsulation, Lipid nanoparticles, Microfluidics, Micromixer, Multi-agents, Optimization, Process simulation, Sustainability

Background: Nuclear factor erythroid 2-related factor 2 (NRF2) regulates antioxidant defenses and protects against neurodegeneration, including Alzheimer's disease (AD). Its age-related decline disrupts redox balance and increases neuronal vulnerability, but the early hippocampal effects remain unclear. Here, we tested whether NRF2 loss affects tau seeding and spreading in a PHF-tau-inoculated mouse model, contributing to accelerated aging. Methodology: Three-month-old NRF2-knockout (Nfe2l2-/-) and wild-type (WT) mice received hippocampal inoculations of human AD-derived PHF-tau, and tau propagation was analyzed after three months. To elucidate the molecular underpinnings of the observed changes, we performed integrative phosphoproteotranscriptomic analyses of hippocampal tissue, supported by RT-qPCR and Western blot validation. Results: PHF-tau inoculation at 3 months of age in Nfe2l2-/- mice, surprisingly, exhibited markedly reduced tau seeding and spreading compared to WT after 3 months of incubation. Molecular characterization of the Nfe2l2-/- hippocampus was carried out to unravel the molecular changes associated with impaired tau propagation. Transcriptomic profiling revealed 745 deregulated genes in Nfe2l2-/- mice, characterized by upregulation of immune and metabolic pathways but downregulation of oxidative stress and redox-related genes. RT-qPCR confirmed diminished expression of antioxidant enzymes and anti-inflammatory receptors, alongside altered astrocytic markers. Proteomic analysis identified 157 dysregulated proteins associated with mitochondrial, synaptic, and inflammatory processes, while phosphoproteomics detected 824 altered phosphosites enriched in cytoskeletal and synaptic networks. Western blot showed increased GFAP-C-term, AQP4, 8-OHdG, and MDAL, with reduced GSTM2 expression. Notably, total and 4R-tau levels were decreased, while 3R-tau was elevated in Nfe2l2-/- mice. Conclusion: Our findings suggest that NRF2 loss induces a hippocampal state marked by impaired antioxidant defenses, astrocytic remodeling, and disrupted tau isoform balance. This environment, while metabolically altered, paradoxically hinders tau propagation, highlighting NRF2 as a key regulator of both redox and cellular maturity programs essential for tau spread and as a potential therapeutic target in tauopathies.

JTD Keywords: Aging, Alzheimer's disease, Brain, Disease progression, Expression, Fibrillary acidic protein, Inflammation, Mutations, Nrf2, Oxidative stress, Rat, Receptor, Tau, Transgenic mice

Amyloid fibrils formed by the islet amyloid polypeptide cause pancreatic beta-cell damage, resulting in reduced insulin secretion and type 2 diabetes. Changes in the amino acid sequence of this peptide can influence its aggregation rate, and animals expressing variants that do not form amyloids do not develop type 2 diabetes. Conversely, specific single amino acid changes can accelerate the aggregation rate of this peptide. Here, we employ deep mutational scanning to measure the ability of 1916 islet amyloid polypeptide variants, including substitutions, insertions, truncations and deletions, to nucleate amyloids. Our results identify a continuous stretch of residues from 15 to 32 that is particularly sensitive to mutation. This region, which is likely structured in amyloids, matches the core of the early aggregated species formed by this peptide in vitro. Within this region, mutations in residues 21 to 27 have a substantial effect, suggesting tighter structural constraints. Finally, we compare the mutational atlas of the islet amyloid polypeptide to that of amyloid beta - the peptide that aggregates in Alzheimer's disease - and find that mutations that slow down nucleation correlate between the two amyloids, but mutations that accelerate nucleation in one amyloid cannot be used to predict mutational effects in the other.

JTD Keywords: Aggregation, Amylin gene, Amyloidogenicity, Atomic-resolution structure, Beta, Cryo-em structures, Diabetes-mellitus, Fibril structure, Islet, Polypeptide iapp

Neurodegenerative diseases, like Alzheimer's disease (AD), are characterized by the accumulation of tau aggregates, leading to neuronal dysfunction and cognitive decline. This study explores the development of dual-acting compounds combining sigma-1 receptor (sigma R-1) agonists and histone deacetylase inhibitors (HDACi) to target these pathological mechanisms. Compounds 2d and 3a demonstrated high affinity for sigma R-1 and significantly reduced tau aggregation and phosphorylation in vitro, notably at the AT8 epitope. These dual-acting compounds destabilized tau aggregates, increased tau solubility, and showed favorable pharmacokinetic properties, with compound 2d exhibiting enhanced chemical stability and longer half-life than 3a. In vivo, both compounds confirmed a sigma R-1 agonist profile by reversing the effect of the sigma R-1 antagonist BD-1063. This dual-action approach, acting on both HDAC and sigma R-1 pathways, holds significant potential for treating tauopathies. While further optimization and clinical evaluation are needed, these findings provide a strong foundation for the continued development of multimodal therapies for neurodegenerative diseases treatment.

JTD Keywords: Alzheimers, Amyloid-beta, Anavex2-73, Dual-acting compounds, Hdac inhibitors, Histone deacetylase, Ligands, Neurodegenerative diseases, Neuroprotection, Pathogenesis, Phenylbutyrate, Phenylbutyric acid, Phosphorylation, Sigma 1r agonists, Sigma receptors (sigma rs), Sigma(1) receptors, Tau protein, Valproic acid

The accumulation of microplastics (& micro;Pls) in ecosystems has become a serious environmental concern. Despite increasing awareness, the development of efficient technologies for their removal and remediation remains a major challenge. Herein, we investigate the photocatalytic degradation of polypropylene (PP) & micro;Pls using nanocomposite catalysts composed of permanently polarized hydroxyapatite microparticles (pp-HAp) and rutile TiO2 nanoparticles (TiO2 NPs). pp-HAp, a macroporous bioceramic, is known for its ability to convert gases (CO2 or/and N2) into small value-added chemical products. While pp-HAp serves both as the substrate and thermocatalytic part of the composite, TiO2 NPs are incorporated as the photocatalytic component. A series of XTiO2/ pp-HAp photocatalyts, where X represents the weight percentage of TiO2 (X = 2.5, 5, 10 and 20), were prepared applying a thermal stimulated polarization treatment. The resulting materials show no formation of undesirable calcium titanate. After thorough chemical and physical characterization, the photocatalytic performance of the XTiO2/pp-HAp in the degradation of PP-& micro;Pls was evaluated. Under 1 sun irradiation, the process is selective toward ethanol, which indicates the cleavage of consecutive C-C bonds along the PP chains, with the highest yield obtained for 2.5TiO2/pp-HAp. When the irradiation intensity decreases (0.5 sun), ethanol and isopropanol are produced, suggesting a reduction in the efficiency of the C-C cleavage. In all cases, the nanocomposite catalysts exhibit significantly higher yields than TiO2 NPs or pp-HAp individually, which indicates cooperative electronic effects between both components. Regarding selectivity, in addition to the solar irradiation, the TiO2: pp-HAp ratio also determines which product is obtained. Within the framework of circular economy, our strategy yields added-value chemical products from PP waste using only sunlight and an environmentally friendly catalyst.

JTD Keywords: Anatase, Heterogeneous catalysis, Microplastics, Microplastics removal, Nanocomposites, Photocatalysts, Polypropylene photodegradation, Water treatment plants

Cells sense mechanical forces and convert them into biochemical signals - a phenomenon called mechanotransduction, which regulates fundamental processes in health and disease. Cells can also be engineered to have exogenous, artificial mechanotransduction mechanisms; such systems implement a synthetic form of mechanotransduction, which could be applied to revert malignant phenotypes, modulate immunotherapies or to develop diagnostic tools. Here we review the status of the nascent field of synthetic mechanotransduction. First, we summarize the types of molecular mechanism known to be involved in endogenous mechanotransduction. Then, we explain how, by taking inspiration from endogenous systems, synthetic mechanotransduction systems have been developed. In its simpler form, these systems involve the expression of synthetic genes responding to natural force-sensing (mechanosensitive) proteins. In a more advanced form, they also include synthetic mechanosensitive proteins. Additionally, other systems have been developed to control force generation itself, resulting in control of tissue shape and function. Finally, we review general considerations for the design of synthetic mechanotransduction systems, and future challenges and opportunities.

JTD Keywords: Activation, Cell-adhesion, Fluid shear-stress, Force transmission, Integrin, Mechanical-stress, Membrane tension, Notch, Nuclear-envelope, Optogenetic control

Neurodegenerative conditions, including Alzheimer's, Parkinson's, amyotrophic lateral sclerosis, and Huntington's disease, represent a critical medical challenge due to their increasing prevalence, severe consequences, and absence of curative treatments. Beyond the need for a deeper understanding of the fundamental mechanisms underlying neurodegeneration, the development of effective treatments is hindered by the blood-brain barrier, which poses a major obstacle to delivering therapeutic agents to the central nervous system. This review provides a comprehensive analysis of the current landscape of nanoparticle-based strategies to overcome the blood-brain barrier and enhance drug delivery for the treatment of neurodegenerative diseases. The nanocarriers reviewed in this work encompass a diverse array of nanoparticles, including polymeric nanoparticles (e.g. micelles and dendrimers), inorganic nanoparticles (e.g. superparamagentic iron oxide nanoparticles, mesoporous silica nanoparticles, gold nanoparticles, selenium and cerium oxide nanoparticles), lipid nanoparticles (e.g. liposomes, solid lipid nanoparticles, nanoemulsions), as well as quantum dots, protein nanoparticles, and hybrid nanocarriers. By examining recent advancements and highlighting future research directions, we aim to shed light on the promising role of nanomedicine in addressing the unmet therapeutic needs of these diseases.Graphical AbstractSchematic representation of the different types of nanoparticles used to tackle neurodegeneration.

JTD Keywords: Blood-brain barrier, Central nervous system deliver, Central-nervous-system, Drug-delivery, Gold nanoparticles, In-vitro, Messenger-rn, Nanocapsules promotes, Nanomedicines, Neurodegenerative diseases, Oxide nanoparticles, Polymeric nanoparticles, Receptors targeting, Solid lipid nanoparticles, Targeted delivery

Growth factor mimetics offer great potential for osteogenic biomaterials; yet, their use remains limited, likely due to an incomplete understanding of the effects of the microenvironment on their activity. The extracellular matrices (ECMs) where growth factors are presented in vivo are viscoelastic environments, where dynamic receptor-ligand interactions drive cellular responses. Here, supported lipid bilayers of varying viscosity are used as 2D dynamic ECM models, where the bone morphogenetic 2 (BMP-2) mimetic DWIVA is presented to mesenchymal stem cells alongside the adhesive peptide RGD. DWIVA is demonstrated to have no impact on mechanotransductive processes, including actin organisation, focal adhesion formation and YAP localisation, which are exclusively controlled by viscosity via RGD. Interestingly, DWIVA promotes osteogenic markers' expression only on a viscous bilayer, through a process that involves non-canonical BMP-2 pathways; on a mobile bilayer or on a static control, it lacks osteogenic activity. Crucially, osteogenesis is accompanied by a translocation of BMP receptor 1a to the cell edge, where it colocalises with focal adhesions. Our ECM models hence reveal that both a viscosity-enabled threshold of cell-generated forces and a dynamic environment are necessary to harness the osteogenic potential of DWIVA, uncovering key microenvironment properties for the design of DWIVA-based biomaterials.

JTD Keywords: Activated protein-kinase, Adsorption, Bmp-2, Bone, Cells, Differentiation, Dwiva, Dynamics, Lipid-bilayers, Mesenchymal stem cell, Microscopy, Osteogenesis, Receptor, Viscosity

Light-induced membrane fusion has become a pivotal technique for constructing and functionalizing synthetic cells by enabling precise control over membrane merging events. Traditional fusion approaches that rely on chemical, physical, and mechanical stimuli frequently lack both specificity and reversibility, limiting their utility in mimicking dynamic cellular processes. Here, we review advances employing photosensitive molecules and optogenetic tools that facilitate spatiotemporally controlled fusion of lipid and polymer vesicles, enabling dynamic content exchange and membrane remodeling. These approaches have enhanced synthetic cell assembly, molecular transport, and signal transduction, with applications extending to drug delivery and biosensing. Despite challenges in efficiency and biocompatibility, ongoing innovations in photosensitizer design and light activation strategies promise to expand the capabilities of synthetic biology platforms. This work underscores the potential of light-induced fusion to advance the development of intelligent nanomaterials and functional synthetic cellular systems.

JTD Keywords: Compartments, Light-induced membrane fusion, Lipid vesicles, Nanoparticles, Nanotechnology, Optogenetic tools, Photoinduced fusion, Release, Synthetic cells, Systems, Vesicles

Calcium phosphate 3D printing has revolutionized customized bone grafting. However, its inherent fragility limits clinical applicability. In this work, this problem is overcome by designing a composite scaffold able to harden in vivo. An alpha-tricalcium phosphate/polycaprolactone scaffold is developed that is ductile and tough when freshly printed and undergoes a transformation to hydroxyapatite following implantation in the body, resulting in its hardening. The hardening reaction, that takes place under physiological conditions and its impact on the biological response and osteogenic capacity of the material are investigated, both in vitro and in vivo, by comparing the in vivo hardening scaffolds with 3D printed hydroxyapatite and hydroxyapatite/polycaprolactone counterparts. In vitro results confirm the bioactivity, osteogenicity, and immunomodulatory potential of the polycaprolactone-based scaffolds. MG-63 cells increase the expression of osteogenic markers, while a downregulation of proinflammatory cytokines is observed in RAW246.7 cells. In vivo evaluation in a rabbit model confirms progressive bone infiltration and maturation, while osteoclast-mediated scaffold degradation is observed, being gradually resorbed and replaced by newly formed bone. Overall, in vivo hardening alpha-tricalcium phosphate/polycaprolactone scaffolds achieve mechanical properties comparable to human trabecular bone while retaining the biocompatibility and osteogenic potential of biomimetic hydroxyapatite.

JTD Keywords: 3d printing, Biomaterials, Bone regeneration, Bone tissue engineering, Cells, Hydroxyapatite, Macrophages, Polarization, Regeneration, Size, Synthetic bone graft

Epithelial tissues undergo complex morphogenetic transformations driven by cellular and cytoskeletal dynamics. To understand the emergent tissue mechanics resulting from sub-cellular mechanisms, we formulate a fully nonlinear continuum theory for epithelial shells that coarse-grains an underlying 3D vertex model, whose surfaces are in turn patches of active viscoelastic gel undergoing turnover. Our theory relies on two ingredients. First, we relate the deformation of apical, basal and lateral surfaces of cells to the continuum deformation of the tissue mid-surface and a thickness director field. We explore two variants of the theory, a Cosserat theory accommodating through-thickness tilt of cells, and a Kirchhoff theory assuming that lateral cell surfaces remain perpendicular to the mid-surface. Second, by adopting a variational formalism of irreversible thermodynamics, we construct an effective Rayleighian functional of the tissue constrained by the cellular-continuum kinematic relations, which therefore depends on continuum fields only. This functional allows us to obtain the governing equations of the continuum theory and is the basis for efficient finite element simulations. Verification against explicit 3D cellular model simulations demonstrates the accuracy of the proposed theory in capturing epithelial buckling dynamics. Furthermore, we show that the Cosserat theory is required to model tissues exhibiting apicobasal asymmetry of active tension. Our work provides a general framework for further studies integrating refined subcellular models into continuum descriptions of epithelial mechanobiology.

JTD Keywords: Active gels, Cortex, Epithelial mechanics, Mechanobiology, Monolayers, Morphogenesis, Thin shells, Vertex models

Supramolecular self-assembled systems have emerged as versatile platforms for engineering biomimetic environments that precisely regulate cellular behavior. These materials have tunable properties such as stiffness, hydrophobicity, and molecular composition, allowing for customization of their structure and function. Despite significant advances, the specific role of electrostatic properties in modulating cellular responses within supramolecular assemblies remains poorly understood. Here, a peptide library with diverse electrostatic profiles is designed to systematically investigate their influence on the bioactivity of supramolecular assemblies for neural regeneration. Combining computational and experimental methods, the self-assembly conditions of these peptides are optimized to create stable, biologically relevant architectures. Using human neural progenitor cell (hNPC) cultures, it is demonstrated that negatively charged environments enhance cell survival and promote neuronal differentiation. Specifically, high negative charges activate critical signaling pathways, including the mitogen-activated protein kinase (MAPK) cascade and cell adhesion mechanisms, leading to neuronal lineage commitment. This study establishes a novel framework for the design of supramolecular systems, offering an unprecedented ability to analyze specific parameters in cell behavior. By achieving control beyond conventional biomaterials, this work provides valuable insights into the complex interplay of biophysical and biochemical cues in the native neural microenvironment, with implications for regenerative medicine and biomaterial design.

JTD Keywords: Charge screening, Death, Design, Extracellular-matrix, Force-field, Human neural progenitor cells, Membrane, Molecular dynamics, Nervous-system, Proteomics, Scaffolds, Self-assemblies, Supramolecular structures

The degeneration of the muscle in muscle dystrophies involves complex interactions among the different cell types. Here, we have used datasets from single-nuclei RNA sequencing (snRNAseq) of Duchenne Muscular Dystrophy (DMD) muscle samples to study the dysregulation of molecular pathways compared to healthy control muscle. We have observed that the epidermal growth factor (EGF) signaling is upregulated in DMD by an increase of the ligands EGF and EGF containing fibulin extracellular matrix protein 1 (EFEMP1). This study explores the role of EGF and EFEMP1 in FAPs and myoblasts in vitro. We provide evidence that EFEMP1 is secreted by FAPs in DMD and is mainly involved with increased myotube size but without enhancing muscle strength. Conversely, EGF enhances fibrotic differentiation in FAPs and promote smaller, proliferative myotubes in myoblasts, aligning with a fibrotic and dysfunctional muscle phenotype in DMD. The cellular differences from both ligands can be explained by the interactions with the receptor type, with EGF activating both EGFR and ErbB2, while EFEMP1 selectively maintained ErbB4 in an inactive state but promoting EGFR-ErbB2 and ErbB2-ErbB4 heterodimerization, potentially enhancing EGF signaling. Consequently, this study examinates the alteration of the EGF signalling in DMD and provides new molecular interactions in muscle that can be useful for targeted therapies of muscle degeneration.

JTD Keywords: Deposits, Efemp1, Migration, Regeneration, Satellite cells

The growing demand for safer, more targeted therapeutics requires the development of advanced biomaterials. Among these, Engineered Living Materials (ELMs)-which integrate synthetic biology with material science-are emerging as promising platforms for biomedical applications. This review focuses on a subclass of ELMs based on genetically engineered probiotics combined with matrices, that are termed Probiotic Living Materials (PLMs) to differentiate them from Living Biotherapeutic Products (LBPs). Recent studies highlight PLM's potential in addressing different health conditions, offering targeted and dynamic therapies. However, PLMs face multiple challenges to be implemented in clinics, including a lack of robust genetic toolkits for probiotic engineering, concerns about biosafety (e.g., horizontal gene transfer or non-desirable biological activity), difficulties in translating preclinical results to humans, and the absence of clear regulatory guidance for clinical use. This review first explores the fundamental features of ELMs, then provides an overview of probiotics, followed by recent advances in the design of engineered PLMs for biomedical applications, particularly in biosensing development, infection treatment, bone repair, wound healing, vaginal imbalances, gut-related conditions, and cancer therapy. Finally, biosafety issues and current gaps in regulatory frameworks to ensure safe and effective use of PLMs, with a particular focus on vulnerable populations, are discussed.

JTD Keywords: Animals, Artificial-intelligence, Biocompatible materials, Clinical-trials, Commensal bacterium, Engineered lactococcus-lactis, Engineered living materials, Escherichia-coli, Gene-expression, Humans, Probiotics, Protein, Saccharomyces-cerevisiae, System, Therapeutics, Yeast

Astrocytes are central to brain homeostasis, supporting neuronal metabolism, synaptic activity, and the blood-brain barrier. With aging, these glial cells undergo molecular and functional changes that weaken support functions and promote neuroinflammation, contributing to neurodegeneration. Yet the systems-level mechanisms by which astrocytes respond to aging-related stressors remain poorly defined in human models. Because aging also heightens risk for cardiovascular disease, cognitive impairment, type 2 diabetes, and systemic inflammation, clarifying shared astrocytic pathways is critical for understanding brain-body crosstalk. Using an in vitro human astrocyte model exposed to sublethal oxidative stress (10 mu M H2O2) as a proxy for age-related cellular stress, we profiled transcriptomic changes and identified differentially expressed genes across antioxidant defenses, proteostasis, transcriptional regulation, vesicular trafficking, and inflammatory signaling. We then performed network-prioritization analyses on a curated human protein-protein interactome: one seeded with the astrocyte oxidative stress responsive genes and six with phenotype-associated gene sets (Alzheimer's disease, cardiovascular disease, cognitive impairment, type 2 diabetes, oxidative stress, and inflammation). Intersecting the top 5 % scoring genes from each run yielded a 127-gene core shared across all seven, enriched for proteostasis, DNA repair, mitochondrial regulation, and telomere and nuclear envelope maintenance. Structure-guided analyses highlighted vulnerable interfaces, including lamin A/C-lamin B1, alpha-actinin-filamins, 14-3-3 dimers, and aminoacyl-tRNA synthetase assemblies, where pathogenic variants are predicted to destabilize or aberrantly stabilize protein interactions. Structure-based interface predictions also highlight potential interactions between amyloid precursor protein (APP) and valosin-containing protein (VCP), and between p53 and 14-3-3 zeta, poten-tially linking proteostasis and stress signaling. Together, these analyses identify a conserved astrocyte-centered network signature that may relate neurodegenerative and cardiovascular processes, and prioritize structurally testable candidates for biomarker and intervention hypothesis testing.

JTD Keywords: 14-3-3-zeta, Aging-associated proteomic remodeling, Astrocytic vulnerability networks, Crosstalk, Disease, Dysfunction, Insights, Interactome, Interfaces, Mutations, Network-based gene-disease prioritization, Neurodegeneration-cardiovascular disease, Oxidative stress-responsive astrocyte pathways, Phosphorylation, Prediction, Proteostasis and mitochondrial dysfunction, Receptor, Structurally vulnerable proteinprotein, Structure-guided variant impact prediction, Telomere and nuclear envelope integrity, Update

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

Implant-associated infections, primarily resulting from bacterial colonization, represent a significant challenge that frequently leads to implant failure. Antibacterial coatings, particularly those incorporating antimicrobial peptides (AMPs), offer a promising strategy for mitigating these infections. However, the application methods for these coatings-whether chemical or physical-face considerable challenges regarding stability and efficacy. In this study, we introduce a novel approach that employs zinc oxide nanoparticles (ZnONP) as an intermediary physical adhesive layer between titanium implants and the self-assembled AMP GL13K. The incorporation of ZnONP enhances hydrogen bonding interactions, facilitated by the nanostructured interface and the abundant hydroxyl groups on the ZnONP surface, thereby significantly improving the stability of the coating. Additionally, GL13K and ZnONP demonstrate synergistic antibacterial and immunomodulatory effects, as validated through in vitro and in vivo studies. The enhanced stability of the coating, combined with improved antibacterial, antiinflammatory, and osteogenic properties, collectively promotes osseointegration of mini-implants in a rat tibia infection model. Given the adaptability of this nanocoating system with other nanoparticles to further enhance hydrogen bonding, we propose it as a potential versatile solution for the supramolecular peptide coating of a diverse range of medical devices.

JTD Keywords: Antimicrobial peptide, Hydrogen bonding, Implant-associated infection, Self-assembly

Neuroblastoma (NB) is among the most common malignancies in children and represents a therapeutic challenge in pediatric oncology. p53 family proteins play a critical role in protecting cells from genomic instability and malignant transformation. However, in NB, their activities are often inhibited by interacting proteins such as MDM2. The interplay between p53 family pathway and N-Myc, a key biomarker of poor prognosis, is also a critical factor in NB pathogenesis. Herein, we disclose 1-(dibromomethyl)-3,4,6-trimethoxy-9H-xanthen-9-one (LEM3) as a new p53 family-activating agent with potent NB anticancer activity. At 0.13-2.1 mu M, LEM3 inhibited the growth of several NB cell lines. Its activity was further evidenced in spheroids, patient-derived NB cells, and in a vasculature stiffness-based model of MYCN-amplified NB cells. This growth-inhibitory effect was associated with cell cycle arrest and apoptosis, in SH-SY5Y and SK-N-BE(2) NB cells, without apparent acquisition of resistance. LEM3 inhibited cell migration and invasion and reduced the expression of NB-related prognostic markers, particularly MYCN mRNA and protein levels. LEM3 released p53, TAp63, and TAp73 from their interaction with MDM2 both in a yeast-based assay and NB cells; for p53, this led to increased protein stabilization, DNA-binding ability, and transcriptional activity. Fluorescence quenching and docking analyses suggested that LEM3 binds to p53, TAp63, and TAp73 at the MDM2-binding site within their transactivation domain. LEM3 also synergies with doxorubicin and cisplatin in NB cells. Given the central role of the p53 family MDM2-MYCN axis in NB pathogenesis, our findings support LEM3 as a promising compound for advancing NB targeted therapy.

JTD Keywords: Amplification, Cell-lines, Expression, High-risk neuroblastoma, Mdm2, Mutant p53, N-myc, N-myc oncogene, Neuroblastoma, P53 family proteins, P53/mdm2/p14(arf) pathway, P73, Sensitizes neuroblastoma, Targeted anticancer therapy, Xanthone derivative

Sleep apnea is common but often underdiagnosed after stroke, hindering rehabilitation and functional recovery. Access to sleep studies remains limited for stroke patients, partly due to the inconvenience of current diagnostic tools. The widespread availability and built-in sensors of smartphones make them powerful solutions for mobile health applications, including sleep monitoring. This study aims to detect and evaluate sleep apnea in post-stroke patients using a smartphone and extract multimodal digital biomarkers to characterize their sleep patterns. For that, overnight sleep tests were conducted on 30 subacute stroke patients and 30 age- and sex-matched control subjects, using a smartphone-based system that recorded audio, accelerometer, and oximetry data. Signals were analyzed with custom-made algorithms to compute respiratory, oxygenation, and sleep position indices. Results showed that the apnea-hypopnea index (AHI) was significantly higher in the stroke than the control group (28 +/- 19 vs 14 +/- 11, p = 0.006). Moderate-to-severe sleep apnea (AHI >= 15) was present in 67% of stroke patients and 40% of control subjects. Stroke patients spent more time mouth breathing (22% vs 12%, p

JTD Keywords: Association, Biomedical signal processing, Entropy, Heart-rate, Ischemic-stroke, Mhealth, Monitoring, Obesity, Oximetry, Positions, Prediction, Prevalence, Sleep apnea, Smartphone, Stroke, Supine sleep, Wearables

Organoids derived from human pluripotent stem (hPS) cells hold promise for therapeutic purposes. However, technological advances to overcome their massive production while ensuring differentiation fidelity are still lacking. Here we report a procedure sustaining the derivation of kidney organoids from hPS cells (hPSC-kidney organoids) using a scalable, reproducible and affordable approach that allows hPSC-kidney organoid differentiation into different renal cell types. Using single-cell RNA sequencing, confocal image analysis, metabolic assays and CRISPR-Cas9 engineering for generation of fluorescent reporters, we show that hPSC-kidney organoids exhibit transcriptional variety and cellular composition following cell-to-cell contact. We infuse human kidney organoids into ex vivo porcine kidneys using normothermic machine perfusion, and demonstrate in vivo engraftment of hPSC-kidney organoids. We further evaluate the immune response, confirming the feasibility and viability of the procedure. We identify cells of human origin after normothermic machine perfusion and in vivo transplantation by means of in situ hybridization, immunohistochemistry, confocal microscopy, image analysis and quantification, in vivo imaging, and flow cytometry. This work provides a foundation for using hPSC-kidney organoids for ex vivo cell-based therapies in clinical trials.

JTD Keywords: Divergent features, Mouse, Reveals, Static cold-storage

Biological sex significantly influences the prevalence, incidence, and severity of numerous human diseases, yet it remains an underappreciated variable in biomedical research. Although sexually dimorphic genes contribute to sex-specific traits and disease manifestations, their regulation under metabolic stress is poorly understood. To explore sex-specific metabolic adaptations, we analyzed responses to high-fat diet (HFD)-induced obesity in male and female mice, focusing on the regulation of sex-biased genes. Despite similar adiposity, HFD-fed males displayed more severe metabolic impairments than females, highlighting divergent metabolic outcomes. To investigate the basis for these sex-specific differences, we performed whole transcriptomic profiling of liver and white adipose tissue (WAT) at early (2 wk) and late (12 wk) stages of HFD exposure. Our analysis revealed marked sex-specific gene expression changes across multiple categories, particularly pronounced in male WAT after prolonged HFD feeding. Strikingly, genes exhibiting sexual dimorphism under normal conditions were preferentially modulated in both sexes, comprising up to 46% of all HFD-regulated genes. This led to a substantial loss of sex-biased gene expression in both liver and WAT after HFD exposure, correlating with metabolic dysfunction. Male-biased genes associated with cilia function and estrogen response were among the most affected, showing significant downregulation in male WAT under HFD. Our findings provide a novel perspective on how obesity disrupts sex-specific gene expression in key metabolic tissues, particularly targeting sex-biased genes. By revealing that a considerable proportion of sex-biased genes exhibit HFD-regulated modulation, our study highlights the critical role of these genes in maintaining metabolic health. NEW & NOTEWORTHY Biological sex shapes metabolic tissue physiology, largely through sex-biased gene regulation. Our comprehensive transcriptomic analysis reveals that sex-biased genes in liver and white adipose tissue undergo the most significant regulation during obesity-driven metabolic dysfunction, resulting in a loss of their bias. This disruption highlights a previously unrecognized role of sex-biased genes in maintaining metabolic health in both males and females.

JTD Keywords: Er-alpha, Estrogen-receptor, Female, Gender-differences, High-fat-diet, Insulin resistance, Insulin-resistance, Mitochondrial-function, Obesity, Oxidative-metabolism, Sex differences, Sex-differences, Transcriptomics, Type 2 diabetes, White adipose-tissue

Lafora disease (LD) is a fatal childhood progressive myoclonus epilepsy and glycogen storage disease that is caused by recessive mutations in either EPM2A or EPM2B. The hallmarks of LD are cytoplasmic, aberrant glycogen-like aggregates, called Lafora bodies (LBs), that drive disease progression. The 9th Annual Lafora Science Symposium was held in San Diego, California and brought together over 70 researchers, clinicians, academic trainees, and friends and family members of patients with LD and 80 attendees joined virtually. This symposium focused primarily on international collaborations for therapeutic development and biomarker identification and strategies for preparing the Lafora community for upcoming clinical trials.

JTD Keywords: Childhood dementia, Cytoplasmic glycogen, Efficacy, Gene, Glycogen, Glycogen storage disease, Lafora disease, Mutations, Myoclonus epilepsy, Phosphatase, Progressive myoclonus epilepsy

BackgroundCollective migration is the coordinated movement of a group of cells-a fundamental process in health and disease. Many models have been developed to study the molecular and physical mechanisms of collective migration. However, the aim of this study is to engineer a flexible in vitro framework that allows for mechanobiological quantification of the separate and combined contributions of individual cell mechanics to the directed migration of a collective. We utilised this framework to understand the role of juxtacrine Notch signalling during collective endothelial migration-an essential process during the formation of new blood vessels (known as angiogenesis).ResultsThis framework enables users to perform high spatiotemporal analysis of migrative behaviour, cell-matrix traction forces, and intercellular forces in different microenvironments. With this framework, we show that Notch inhibited collectives adopt a distinct regime of directed collective migration. Whereas the directionality of migration, traction forces and intercellular forces are not affected by Notch inhibition, we observed spatiotemporal differences in migration speed, traction force magnitude and normal and shear stresses within Notch-inhibited collectives.ConclusionsThe in vitro framework is a powerful approach for dissecting the mechanisms of collective migration. With this framework, we show that a potential link exists between the juxtacrine signalling of Notch and an increased mechanical cohesiveness among collective cells.

JTD Keywords: Angiogenesis, Cell-cell dynamics, Cell-matrix dynamics, Collective endothelial migration, Dynamics, Forces, In vitro framework, Juxtacrine notch signalling, Migration kinematics, Morphogenesis, Organization

3D-printing has emerged as a leading technology for fabricating personalized scaffolds for bone regeneration. Among the 3D-printing technologies, vat photopolymerization (VP) stands out for its high precision and versatility. It enables the creation of complex, patient-specific scaffolds with advanced pore architectures that enhance mechanical stability and promote cell growth, key factors for effective bone regeneration. This review provides an overview of the advances made in vat photopolymerization printing of calcium phosphates, covering both the fabrication of full ceramic bodies and polymer-calcium phosphate composites. The review examines key aspects of the fabrication process, including slurry composition, architectural design, and printing accuracy, highlighting their impact on the mechanical and biological performance of 3D-printed scaffolds. The need to tailor porosity, pore size, and geometric design to achieve both mechanical integrity and biological functionality is emphasized by a review of data published in the recent literature. This review demonstrates that advanced geometries like Triply Periodic Minimal Surfaces and nature-inspired designs, achievable with exceptional precision by this technology, enhance mechanical and osteogenic performance. In summary, VP's versatility, driven by the diversity of material options, consolidation methods, and precision opens new horizons for scaffold-based bone regeneration.

JTD Keywords: 3d printing, Additive manufacturing, Bioceramic scaffolds, Bone regeneratio, Ceramic scaffolds, Composite scaffolds, Fabrication, Ha scaffolds, Hydroxyapatite, Hydroxyapatite scaffolds, Mechanical-properties, Regeneratio, Scaffold, Stereolithography, Titanium surfaces, Vat polymerization

Thanks to their biocompatibility and ability to support cell growth, alginate hydrogels are promising scaffolds for skin tissue regeneration. If conductive, they can further improve the wound healing process by electrical stimulation (ES). Herein, we explore the preparation and application of robust hydrogels synthesized via the thiol-yne click reaction, a highly efficient and rapid process. Hydrogels were obtained by functionalizing alginate with thiol groups and crosslinking them with a modified 3-arm polyethylene glycol (PEG) precursor (click-Alg). As a final step, the in situ chemical oxidative polymerization of poly(hydroxymethyl-3,4-ethylenedioxythiophene) (semi-interpenetrated PHMeEDOT) rendered them electro-responsive (click-Alg/PHMeEDOT). The gelation of the click-Alg hydrogels proceeded quickly (within 3 min), enabling rapid network formation for injectable application and resulting in high gel fraction, which ensured structural stability. After incorporating PHMeEDOT, a decrease in the pore size happened, while porosity remained predominantly open, with PHMeEDOT completely covering the pores surface. This coating enhanced the electrochemical response of click-Alg/PHMeEDOT hydrogels, whereas their mechanical similarity (with values of Young's modulus = 116 +/- 10.7 kPa) to skin tissue is expected to reduce mismatch risks, improve integration, and minimize stress-related healing issues. Optimized in vitro assays with Vero and HFF-1 cells subjected to 0.6 V for 20 min showed significant wound closure after 2 h, implying that increased electrochemical activity played a key role in promoting wound closure under ES. Overall, we highlight the synergy between both matrices and the effectiveness and potential of click-Alg/PHMeEDOT hydrogels as electrode-like wound dressings for electrically-driven skin tissue repair.

JTD Keywords: Alginate, Behavior, Cell, Collagen, Conducting polymer, Conductivity, Electrical stimulation, Fabrication, Hyaluronic-acid hydrogel, Hydrogel, In-vivo, Membranes, Model, Network, Thiol-yne click chemistry, Wound dressing

Electron transfer (ET) between redox proteins is an essential process in the respiratory and photosynthetic transport chains. While intra-protein ET is well characterized, the experimental methods to investigate inter-protein ET are limited by the presence of the solvent and by the transient nature of the protein-protein interaction and ET event, which are averaged in protein ensembles. Wiring precisely oriented redox protein partners to the nanoscale electrodes of an electrochemical scanning tunneling microscope allows recording the time- and distance-dependence of the current flowing between them. These methods have revealed that the current flowing between individual protein pairs extends beyond tunneling distances and that it is electrochemically gated. However, the corresponding mechanism and the identity of the charge carriers in aqueous solution remain to be elucidated. To determine the species involved in long-distance charge transport between the redox partner proteins Cc and Cc 1 of the respiratory chain, recordings are performed as a function of pH, in heavy water solutions, and in degassed solutions. It is observed that the spatial span and electrochemical gating of long-distance currents are reduced at high pH, in heavy water, and at low oxygen concentration, showing that the currents are assisted by superoxide anions and by protons.

JTD Keywords: Catalysis, Coupled electron-transfer, Dynamics, Electrochemical stm, Gouy-chapman conduit, Grotthuss (grothuss) proton hopping conduction, Interface, Kinetic isotope effect kie, Mechanism, Mitochondria, Pathways, Ph, Proteins, Proton coupled electron transfer pcet, Reactive oxygen species ros, Reductase, Superoxide radical anion sox, Tyrosine phosphorylation

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

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

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

Cardiac tissues are difficult to regenerate due to the low proliferative capacity of cardiomyocytes. A new therapeutic strategy for cardiac regenerative medicine could include a device capable of ensuring cell grafting, stimulating cardiac tissue regeneration, and serving as an appropriate scaffold for the controlled and sustained release of lactate over time as an inducer of cardiomyocyte proliferation. An effective source of lactate could consist of the lactic acid polymer (PLA) itself, which generates free lactic acid during its degradation. In this work, we have developed a nanocomposite hydrogel for lactate release based on a biocompatible and biodegradable matrix formed by elastin-like recombinamers cross-linked via click chemistry. Polylactic acid particles were encapsulated in the matrix after these particles had been partially degraded to lactic acid through oxygen plasma treatment. In the first 48 h, an early and modulated release of free lactic acid from plasma-treated PLA degradation is observed, and over longer periods, a sustained release of lactic acid produced by the hydrolytic degradation of PLA under physiological conditions occurs. Lactate is available from the very beginning ("early release"), addressing the drawback of the slow degradation (by hydrolysis) of polylactic acid. Therefore, a biomedical device has been designed and implemented, formed by an ELR polymeric matrix as an analogue of cardiac tissue, acting as a device for early, controlled, and sustained lactate release, with dosing at concentrations similar to those previously studied as suitable for promoting cardiomyocyte proliferation, showing promise for its use in the regeneration of infarcted cardiac tissue.

JTD Keywords: Biomaterials, Bone morphogenetic protein-10, Early and sustained releas, Elastin-like polypeptides, Elastin-like recombinamers, Equation, Hydrogel, Nanocomposite, Peptid, Polylactic acid, Solute release

Microscopy is a fundamental tool in biological research. However, conventional microscopes require manual operation and depend on user and equipment availability, limiting their suitability for continuous observation. Moreover, their size and complexity make them impractical for in situ experimentation. In this work, we present a novel, compact, affordable, and portable microscope that enables continuous in situ monitoring by being placed directly on biological samples. This chip-sized lensless holographic microscope (CLHM) is specifically designed to overcome the limitations of traditional microscopy. The device consists solely of an ultra-compact, state-of-the-art micro-LED display and a CMOS sensor, all enclosed within a 3D-printed housing. This unique light source enables a size that is markedly smaller than any comparable technology, allowing a resolution of 2.19 mu m within a 7 mm distance between the light source and the camera. This paper demonstrates the CLHM's versatility by monitoring in vitro models and performing whole-organism morphological analyses of small specimens. These experiments underscore its potential as an on-platform sensing device for continuous, in situ biological monitoring across diverse models.

JTD Keywords: Angiogenesis, Compact microscope, Fermentation, Holography, Lab-on-a-chip, Lensless, Real-time monitoring, Zebrafish

The invasion of human embryos in the uterus overcoming the maternal tissue barrier is a crucial step in embryo implantation and subsequent development. Although tissue invasion is fundamentally a mechanical process, most studies have focused on the biochemical and genetic aspects of implantation. Here, we fill the gap by using a deformable ex vivo platform to visualize traction during human embryo implantation. We demonstrate that embryos apply forces remodeling the matrix with species-specific displacement amplitudes and distinct radial patterns: principal displacement directions for mouse embryos, expanding on the surface while human embryos insert in the matrix generating multiple traction foci. Implantation-impaired human embryos showed reduced displacement, as well as mouse embryos with inhibited integrin-mediated force transmission. External mechanical cues induced a mechanosensitive response, human embryos recruited myosin, and directed cell protrusions, while mouse embryos oriented their implantation or body axis toward the external cue. These findings underscore the role of mechanical forces in driving species-specific invasion patterns during embryo implantation.

JTD Keywords: Animals, Anterior-posterior axis, Biomechanical phenomena, Cells, Collagen, Differentiatio, Embryo implantation, Embryo, mammalian, Female, Humans, Mechanotransduction, cellular, Mice, Morphogenesis, Pregnancy, Range, Self-organization, Species specificity, Trophoblast invasion, Uterine contractions

Despite the natural capacity of extracellular vesicles (EVs) to encapsulate intracellular compounds and transfer these to nearby or distant recipient cells, the intentional loading of EVs with cargo molecules remains a challenging endeavor. Pre-formation EV loading (i.e., during EV biogenesis), offers advantages compared to post-formation loading (i.e., after EV isolation), as EV integrity and composition are minimally perturbed. Pre-formation EV loading is primarily achieved through the genetic engineering of the producer cell, which is time consuming and not very flexible regarding the types of molecules that can be incorporated into EVs. In this work, we investigated the possibility of loading cargo molecules into EVs by delivering the cargo directly into the cytosol of the producer cells, which can subsequently be encapsulated into EVs as they are formed. For the cytosolic delivery of cargo molecules, we evaluated the use of photoporation. This membrane disruption technology has been demonstrated to successfully deliver a broad range of cargo molecules into virtually any cell type, while minimally impacting the cell's normal functioning and homeostasis. As a proof-of-concept, we delivered fluorescently labeled dextran macromolecules and anti-EGFP nanobodies into HEK293T cells genetically engineered with gag-EGFP fusion proteins, which are shuttled into EVs. Colocalization of cargo and EGFP fluorescence in secreted EVs can then serve as a convenient readout for successful EV loading. We established that photoporation had minimal impact on EV characteristics such as concentration, size, zeta potential and the enrichment of EV tetraspanin membrane surface molecules. We found that using EGFP-targeted nanobodies resulted in up to 53% loaded EVs (relative to the amount of EGFP EVs), while non-targeted dextran molecules produced on average 12% loaded EVs (relative to the amount of EGFP EVs). These results highlight the promise of photoporation for pre-formation loading of EVs.

JTD Keywords: Biogenesis, Challenge, Drug-delivery, Exosomes, In-vitro, Macromolecules, Microrna, Nanobubbles, Small interfering rna, Transferrin receptor

Early embryos are exposed to environmental perturbations that may influence their development, including bacteria. Despite lacking a proper immune system, the surface epithelium of early embryos (trophectoderm in mammals) can phagocytose defective pluripotent cells. Here, we explore the dynamic interactions between early embryos and bacteria. Quantitative live imaging of infection models developed in zebrafish embryos reveals the efficient phagocytic capability of surface epithelia in detecting, ingesting, and destroying infiltrated E. coli and S. aureus. In vivo single-cell interferences uncover actin-based epithelial zippering protrusions mediating bacterial phagocytosis, safeguarding developmental robustness upon infection. Transcriptomic and inter-scale dynamic analyses of phagocyte-bacteria interactions identify specific features of this epithelial phagocytic program. Notably, live imaging of mouse and human blastocysts supports a conserved role of the trophectoderm in bacterial phagocytosis. This defensive role of the surface epithelium against bacterial infection provides immunocompetence to early embryos, with relevant implications for understanding failures in human embryogenesis.

JTD Keywords: Embryo, Gene-expression, Highlights, Microbial colonization, Modulation, P, Phagocytosis, Rho, Women

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

Advances in 3D bioprinting have opened new possibilities for developing bioengineered muscle models that can mimic the architecture and function of native tissues. However, current bioengineering approaches do not fully recreate the complex fascicle-like hierarchical organization of the skeletal muscle tissue, impacting on the muscle maturation due to the lack of oxygen and nutrient supply in the scaffold inner regions. A key challenge is the production of precise and width-controlled independent filaments that do not fuse during the printing process when subsequently extruded, ensuring the formation of fascicle-like structures. This study addresses the limitation of filament fusion by utilizing a pluronic-assisted co-axial 3D bioprinting system (PACA-3D) creates a physical confinement of the bioink during the extrusion process, effectively obtaining thin and independent printed filaments with controlled shapes. The use of PACA-3D enabled the fabrication of skeletal muscle-based bioactuators with improved cell differentiation and significantly increased force output, obtaining 3 times stronger bioengineered muscle when compared to bioactuators fabricated using conventional 3D extrusion bioprinting techniques, where a single syringe containing the bioink is used. The versatility of our technology has been demonstrated using different biomaterials, demonstrating its potential to develop more complex biohybrid tissue-based architectures with improved functionality, as well as aiming for better scalability and printing flexibility.

JTD Keywords: 3d bioprinting, Bioengineering, Cells, Co-axial printin, Collagen, Constructs, Gelati, Muscle-based actuators, Pluronic, Tissue

Cellular prion protein (PrPC) and tau are highly expressed in the brain and overlap at the cellular level in neurons. Both proteins contribute directly to neurodegeneration processes in a misfolding state, although in their natural conformation, they play important roles in neurogenesis that could have a common link according to the recent literature. In this sense, it is well known that the proteinase-K resistant PrPC isoform (PrPSc), the prion, is the causal agent of prionopathies. And misfolded tau, which is responsible for tauopathies, is considered "prion-like" because it displays similar behavior to prions in terms of self-aggregation and spreading properties. At the physiological level, PrPC potentiates neuronal differentiation while tau intervenes in axonal maturation and elongation. Likewise, recent studies from our laboratory reported that PrPC directly affects the alternative splicing of tau through inhibition of GSK3 beta while tau, in turn, can regulate PRNP transcription. In this review, we first describe the biology and physiological roles of PrPC and tau in the central nervous system (CNS). Second, in the effort to improve our understanding of a possible cooperation between them in various cellular circumstances, we also discuss the molecular convergence points between PrPC and tau in neurodegeneration and in natural neuronal physiology.

JTD Keywords: Alzheimers-disease, Amyloid-beta, Axonal-transport, Cellular prion protein, Creutzfeldt-jakob-disease, Developmental expression, Gene-expression, Neurodegeneration, Neurofibrillary tangles, Neurogènesi, Phosphorylatio, Straussler-scheinker disease, Tau

Inspired by Richard Feynman's 1959 lecture and the 1966 film Fantastic Voyage, the field of micro/nanorobots has evolved from science fiction to reality, with significant advancements in biomedical and environmental applications. Despite the rapid progress, the deployment of functional micro/nanorobots remains limited. This review of the technology roadmap identifies key challenges hindering their widespread use, focusing on propulsion mechanisms, fundamental theoretical aspects, collective behavior, material design, and embodied intelligence. We explore the current state of micro/nanorobot technology, with an emphasis on applications in biomedicine, environmental remediation, analytical sensing, and other industrial technological aspects. Additionally, we analyze issues related to scaling up production, commercialization, and regulatory frameworks that are crucial for transitioning from research to practical applications. We also emphasize the need for interdisciplinary collaboration to address both technical and nontechnical challenges, such as sustainability, ethics, and business considerations. Finally, we propose a roadmap for future research to accelerate the development of micro/nanorobots, positioning them as essential tools for addressing grand challenges and enhancing the quality of life.

JTD Keywords: Catalytic nanomotor, Chemically powered nanomotors, Collective behavior, Drug-delivery, Functionality, Humans, Intelligence, Janus micromotors, Low-reynolds-number, Metal-organic frameworks, Micro/nanorobots, Motion control, Multiparticle collision dynamics, Nanotechnology, Near-infrared light, Propulsion, Robotics, Self-propelled micromotors, Smart materials, Technological translatio, Technological translation

Integrin alpha 5 beta 1 is crucial for cell attachment and migration in development and tissue regeneration, and alpha 5 beta 1 binding proteins can have considerable utility in regenerative medicine and next-generation therapeutics. We use computational protein design to create de novo alpha 5 beta 1-specific modulating miniprotein binders, called NeoNectins, that bind to and stabilize the open state of alpha 5 beta 1. When immobilized onto titanium surfaces and throughout 3D hydrogels, the NeoNectins outperform native fibronectin (FN) and RGD peptides in enhancing cell attachment and spreading, and NeoNectin-grafted titanium implants outperformed FN- and RGD-grafted implants in animal models in promoting tissue integration and bone growth. NeoNectins should be broadly applicable for tissue engineering and biomedicine.

JTD Keywords: Activation, Alpha(5)beta(1), Biomaterial, Cell, De novo protein design, Differentiation, Fibronectin, Growth-factor-beta, Hydrogel, In-vivo, Integrin alpha 5 beta 1, Ligan, Microscopy, Migration, Regenerative medicine, Rgd, Titaniu

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

We argue that Kazuo Ishiguro's latest novel, Klara and the Sun (2021), portrays an "ustopia" (Margaret Atwood)-a near-future vision that articulates an unresolved tension between utopian and dystopian premises, humanist concerns and posthuman possibilities, anxiety and hope. Klara and the Sun is narrated in the first person by Klara, a child robot endowed with affective, cognitive, and learning capacities, who experiences a world shaped by climate emergency, bioengineering, and AI. Ishiguro's novel builds on familiar sci-fi dystopian motifs, conveying a humanistic anxiety about new forms of inequality generated by genetic enhancement and identity issues arising from the possibility that humanoid robots could replicate and replace humans. However, in contrast to humanist interpretations of Ishiguro's novel, we argue that it also presents the possibility of a "posthuman supplement" to the humanist tradition. Humanoid robots like Klara, capable of creativity, curiosity, and selfless care, open the possibility of a logic of diff & eacute;rance (Jacques Derrida), and thus, novel forms of existence and human-posthuman relationships. The novel envisions meaningful bonds between humans and human-like singularities, as well as new possibilities for mutual learning connected to the creation of AI-driven ecosophical beliefs (F & eacute;lix Guattari) that could counter environmental degradation and alienation from nature.

JTD Keywords: Artificial intelligence, Bioengineering, Ecology, Posthuman humanism, Robot revolution

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

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

The possibility of using light to image and manipulate neuronal activity, at the heart of Neurophotonics, has provided new irreplaceable tools to study brain function. In particular, the combination of multiphoton microscopy and optogenetics allows researchers to interact with neuronal circuits with single-cell resolution in living brain tissues. However, significant optical challenges remain to empower new discoveries in Neuroscience. This Review focuses on three critical areas for future development: (1) expanding imaging and optogenetic stimulation to larger fields of view and faster acquisition speeds, while maintaining single-cell resolution and minimizing photodamage; (2) enabling access to deeper brain regions to study currently inaccessible neuronal circuits; and (3) developing optical techniques for studying natural behaviors in freely moving animals. For each of these challenges, we review the current state-of-the-art and suggest future directions with the potential to transform the field.

JTD Keywords: 2-photon excitation, Adaptive optics, All-optical brain studies, All-optical electrophysiology, Calcium and voltage imaging, Field-of-view, High-speed, In-vivo, Large-scale, Multiphoton microscopy, Neural activity, Neurophotonics, Optogenetic photostimulation, Optogeneticphotostimulation, Primary visual-cortex, Voltage indicator, Wavefront shaping, Wavefrontshaping

Background: Malaria during pregnancy implies a high risk for the mother and the developing child. However, the therapeutic options for pregnant women have historically been very limited, especially during the first trimester of pregnancy due to potential adverse effects on embryo-fetal development. Recently, there has been great controversy regarding these potential embryo-fetal adverse effects because the results of rodent studies were not in accordance with the clinical data available, and finally the WHO has changed the recommendations for pregnant women with uncomplicated P. falciparum malaria to treatment with artemether-lumefantrine during the first trimester. The discrepancy between pre-clinical and clinical studies has been attributed to speciesdifferences in the duration of the window of susceptibility of circulating primitive erythroblasts. Methods: Here we provide a tool based on an alternative method to animal experimentation that accelerates the research of novel drugs for pregnant women. We have adapted the zebrafish embryo developmental toxicity assay to include hemoglobin staining in the embryos and two time-points of lethality and dysmorphogenesis evaluation. These two time-points were selected to include one when the development is independent of and one when the development is dependent of erythrocytes function. The method was used to test four marketed antimalarial drugs and three new antimalarial drug candidates. Results: Our combination of tests can correctly predict the teratogenic and non-teratogenic effects of several antimalarial marketed drugs (artemisinin, quinine, chloroquine, and dihydroartemisinin + desbutyl-lumefantrine). Furthermore, we have tested three new drug candidates (GS-GUAN, DONE3TCl, and YAT2150) with novel mechanisms of action, and different from those of the marketed antimalarial drugs. Conclusions: We propose a decision tree combining the results of the two time-points of evaluation together with the information on significant erythrocyte depletion. The aim of this decision tree is to identify compounds with no or lower hazard on teratogenicity or erythrocyte depletion at an early phase of the drug development process.

JTD Keywords: Alternative methods to animal experimentation, Artesunate, Culture, Dihydroartemisinin, Drug discovery, Embryotoxicity test, In-vitro, Inhibitors, Mode, Nams, Paludism, Rat, Resistance, Safety, Teratogenesis, Toxicity testin

Heterogeneity and the absence of a tumor microenvironment (TME) in traditional patient-derived organoid (PDO) cultures limit their effectiveness for clinical use. Here, Embedded Bioprinting-enabled Arrayed PDOs (Eba-PDOs) featuring uniformly arrayed colorectal cancer (CRC) PDOs within a recreated TME is presented. This model faithfully reproduces critical TME attributes, including elevated matrix stiffness (approximate to 7.5 kPa) and hypoxic conditions found in CRC. Transcriptomic and immunofluorescence microscopy analysis reveal that Eba-PDOs more accurately represent actual tissues compared to traditional PDOs. Furthermore, Eba-PDO effectively capture the variability of CEACAM5 expression-a critical CRC marker-across different patients, correlating with patient classification and differential responses to 5-fluorouracil treatment. This method achieves an uniform size and shape within PDOs from the same patient while preserving distinct morphological features among those from different individuals. These features of Eba-PDO enable the efficient development of a label-free, morphology-based predictive model using supervised learning, enhancing its suitability for clinical applications. Thus, this approach to PDO bioprinting is a promising tool for generating personalized tumor models and advancing precision medicine.

JTD Keywords: Association, Cancer, Carcinoembryonic antigen-expression, Colorectal cancer, Cultur, Differential expression, Embedded bioprinting, Extracellular-matrix, Inter-patient variability, Patient-derived tumor organoid, Stem-cell, Stiffness, Supervised learning, Tissues, Tumor matrix stiffnes

Recent studies have revealed that cardiac tissue regeneration is promoted by administering an initial dose of exogenous lactate and locally maintaining an abundant concentration of this compound for a prolonged period (i.e., around 10-14 days) through sustained release. The aim of this study is to develop a scaffold based on poly(lactic acid) (PLA) for achieving a sustained daily release of lactate from the first day to the end of the recommended period. First, a five-layered electroresponsive scaffold has been engineered using three PLA layers (first, third, and fifth), each composed of electrospun microfibers (MFs), separated by spin coated lactate (second) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) (fourth) intermediate layers. The hydrophobicity of the outer PLA layers (first and fifth) has been used to maintain the release of lactate from the intermediate second layer over 3 days, while the conducting fourth PEDOT:PSS layer has ensured a complete lactate release by electrostimulation. After that, in a second step, the same scaffold has been re-engineered to maintain the sustained release not only for a short period (3 days) but also for a prolonged period (>10 days). For this purpose, the PLA MFs of the intermediate third layer have been substituted by plasma-treated proteinase K-containing PLA MFs, obtained by electrospinning a PLA:enzyme mixture. The activity of the enzyme, which decomposes the ester bonds of PLA, combined with the effect of the plasma on the PLA structure, results in a prolonged sustained release that, in addition, can be modulated.

JTD Keywords: 4-ethylenedioxythiophene), Cardiac tissue regeneratio, Conducting polymer, Drug-release, Electroresponsivescaffolds, Electrospinning, Energy, Enzymatic degradation, Hydrogel, Nanofibers, Poly(3, Poly(lactic acid), Raman-spectroscopy

Cholinergic transmission plays a critical role in both the central and peripheral nervous systems, affecting processes such as learning, memory, and inflammation. Conventional cholinergic drugs generally suffer from poor selectivity and temporal precision, leading to undesired effects and limited therapeutic efficacy. Photopharmacology aims to overcome the limitations of traditional drugs using photocleavable or photoswitchable ligands and spatiotemporal patterns of illumination. Spanning from muscarinic and nicotinic modulators to cholinesterase inhibitors, this review explores the development and application of light-activated compounds as tools for unraveling the role of cholinergic signaling in both physiological and pathological contexts, while also paving the way for innovative phototherapeutic approaches.

JTD Keywords: Azobenzene photoswitches, Binding, Biological-activity, Inhibitors, Muscarinic acetylcholine receptors, Nicotinic acetylcholine receptors, Nicotinic acetylcholine-receptors, Optical control, Photochromic reagents, Photopharmacology, Photoregulatio, Photoswitch, Protecting groups, Release, Uncagin

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

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

Bacteria often carry multiple genes encoding anti-phage defense systems, clustered in defense islands and phage satellites. Various unrelated anti-phage defense systems target phage-encoded homologous recombinases (HRs) through unclear mechanisms. Here, we show that the phage satellite SaPI2, which does not encode orthodox anti-phage defense systems, provides antiviral immunity mediated by Stl2, the SaPI2-encoded transcriptional repressor. Stl2 targets and inhibits phage-encoded HRs, including Sak and Sak4, two HRs from the Rad52-like and Rad51-like superfamilies. Remarkably, apo Stl2 forms a collar of dimers oligomerizing as closed rings and as filaments, mimicking the quaternary structure of its targets. Stl2 decorates both Sak rings and Sak4 filaments. The oligomerization of Stl2 as a collar of dimers is necessary for its inhibitory activity both in vitro and in vivo. Our results shed light on the mechanisms underlying antiviral immunity against phages carrying divergent HRs.

JTD Keywords: Bacteri, Crystal-structure, Escherichia-coli reca, Gene, Inhibition, Mechanism, Pathogenicity island interference, Protein, Rad52, Sos-response

Defining the trajectory of cells during differentiation and disease is key for uncovering the mechanisms driving cell fate and identity. However, trajectories of human cells remain largely unexplored due to the challenges of studying them with human samples. In this study, we investigate the proteome trajectory of iPSCs differentiation to hepatic stellate cells (diHSCs) and identify RORA as a key transcription factor governing the metabolic reprogramming of HSCs necessary for diHSCs' commitment, identity, and activation. Using RORA deficient iPSCs and pharmacologic interventions, we show that RORA is required for early differentiation and prevents diHSCs activation by reducing the high energetic state of the cells. While RORA knockout mice have enhanced fibrosis, RORA agonists rescue multi-organ fibrosis in in vivo models. Notably, RORA expression correlates negatively with liver fibrosis and HSCs activation markers in patients with liver disease. This study reveals that RORA regulates cell metabolic plasticity, important for mesoderm differentiation, pericyte quiescence, and fibrosis, influencing cell commitment and disease.

JTD Keywords: Generation, Inhibition, Mic

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

Sprouting angiogenesis is the formation of new blood vessels from pre-existing vasculature and is of great importance for physiological such as tissue growth and repair and pathological processes, including cancer and metastasis. The multistep process of sprouting angiogenesis is a molecularly and mechanically driven process. It consists of induction of cellular sprout by vascular endothelial growth factor, leader/ follower cell selection through Notch signaling, directed migration of endothelial cells, and vessel fusion and stabilization. A variety of sprouting angiogenesis models have been developed over the years to better understand the underlying mechanisms of cellular sprouting. Despite advancements in understanding the molecular drivers of sprouting angiogenesis, the role of mechanical cues and the mechanical driver of sprouting angiogenesis remains underexplored due to limitations in existing models. In this study, we designed a 2.5D ex vivo model that enables us to mechanically characterize cellular sprouting from a porcine carotid artery using traction force microscopy. The model identifies distinct force patterns within the sprout, where leader cells exert pulling forces and follower cells exert pushing forces on the matrix. The model's versatility allows for the manipulation of both chemical and mechanical cues, such as matrix stiffness, enhancing its relevance to various microenvironments. Here, we demonstrate that the onset of sprouting angiogenesis is stiffness-dependent. The presented 2.5D model for quantifying cellular traction forces in sprouting angiogenesis offers a simplified yet physiologically relevant method, enhancing our understanding of cellular responses to mechanical cues, which could advance tissue engineering and therapeutic strategies against tumor angiogenesis.

JTD Keywords: Cancer, Capillary morphogenesis, Cell, In-vitro, Microscopy, Migration, Traction

ObjectivesThis study evaluated different designs of the conical implant-abutment connection (IAC) and their resistance to microgap formation under oblique loads as specified by the ISO standard for testing dental implants. Also evaluated was the effect of deviations from the ISO specifications on the outcomes.MethodsFinite element analysis was conducted to compare the microgap formation and stress distribution among three conical IAC designs (A, B, and C) in two loading configurations: one compliant with ISO 14801 and one with a modified load adaptor (non-ISO). The different IAC designs varied in the taper, diameter, and cone height. The cone angle mismatch (Cam) between the implant and abutment was considered. A torque of 20 Ncm and oblique loads (up to 400 N) were simulated.ResultsThe stresses produced by the screw-tightening torque varied among the different IAC designs. The contact height was approximately 0.3 mm for Designs A and B, and less than 0.03 mm for Design C. Under oblique loads, Design A maintained IAC sealing without gap formation up to 400 N. With the ISO adaptor, gaps appeared in Design B at 300 N and in Design C at 90 N. The non-ISO adaptor resulted in gap formation at 160 N for Design B and at 50 N for Design C.ConclusionsThe IAC design and cone angle mismatch significantly influenced microgap formation, with some designs showing zero gaps even when the oblique load reached 400 N. The non-ISO adaptor increased gap formation in IACs B and C.

JTD Keywords: Bacterial leakage, Behavior, Dental implant, Dental implant-abutments design, Dimensional measurement accuracy, Finite element analysis, In-vitro, Interface, Mechanical, Peri-implantitis, Scre, Sealant agents, Stres, Taper

We recently characterized the potent antiplasmodial activity of the aggregated protein dye YAT2150, whose presumed mode of action is the inhibition of protein aggregation in the malaria parasite. Using single-dose and ramping methods, assays were done to select Plasmodium falciparum parasites resistant to YAT2150 concentrations ranging from 3x to 0.25x the in vitro IC50 of the compound (in the two-digit nM range) and performed a cross-resistance assessment in P. falciparum lines harboring mutations that make them resistant to a variety of antimalarial drugs. Resistant parasites did not emerge in vitro after 60 days of incubation, which postulates YAT2150 as an 'irresistible' antimalarial. The lyophilized compound is stable for at least one year stored at 25 degrees C. Tests performed in clinical isolates indicated that YAT2150 had also strong activity against Plasmodium vivax (IC50 between 4 and 36 nM) and Leishmania infantum (1.27 and 1.11 mu M), placing it as a unique compound with perspectives of becoming the first drug to be used against both malaria and leishmaniasis.

JTD Keywords: Artemisinin, Complexit, Cross-resistance, Genome, In-vitro, Malaria, Mefloquine, Pfmdr1 gene, Selection

The inclusion of microexons by alternative splicing occurs frequently in neuronal proteins. The roles of these sequences are largely unknown, and changes in their degree of inclusion are associated with neurodevelopmental disorders1. We have previously shown that decreased inclusion of a 24-nucleotide neuron-specific microexon in CPEB4, a RNA-binding protein that regulates translation through cytoplasmic changes in poly(A) tail length, is linked to idiopathic autism spectrum disorder (ASD)2. Why this microexon is required and how small changes in its degree of inclusion have a dominant-negative effect on the expression of ASD-linked genes is unclear. Here we show that neuronal CPEB4 forms condensates that dissolve after depolarization, a transition associated with a switch from translational repression to activation. Heterotypic interactions between the microexon and a cluster of histidine residues prevent the irreversible aggregation of CPEB4 by competing with homotypic interactions between histidine clusters. We conclude that the microexon is required in neuronal CPEB4 to preserve the reversible regulation of CPEB4-mediated gene expression in response to neuronal stimulation.

JTD Keywords: Alternative splicing, Animals, Autism spectrum disorder, Cpeb4 protein, human, Cpeb4 protein, mouse, Exons, Gene expression regulation, Humans, Mice, Neurons, Protein aggregates, Protein biosynthesis, Rna-binding proteins

Multicellularity is one of the major evolutionary transitions, and its rise provided the ingredients for the emergence of a biosphere inhabited by complex organisms. Over the last decades, the potential for bioengineering multicellular systems has been instrumental in interrogating nature and exploring novel paths to regeneration, disease, cognition, and behaviour. Here, we provide a list of open problems that encapsulate many of the ongoing and future challenges in the field and suggest conceptual approaches that may facilitate progress.

JTD Keywords: Biology, Complexity, Differential adhesion, Evolution, Gene network model, Morphogenesis, Origin, Pattern-formation, Principles, Self-organization

There are many examples in nature in which the ability to detect is combined with decision-making, such as the basic survival instinct of plants and animals to search for food. We can technically translate this innate function via the use of robotics with integrated sensors and artificial intelligence. However, the integration of sensing capabilities into robotics has traditionally been neglected due to the significant associated technical challenges. Inspired by plant-root chemotropism, we present a miniaturized electrochemical array integrated into a robotic tip, embedding a customized micro-potentiometer. The system contains solid-state sensors fitted to the tip of the robotic root to three-dimensionally monitor potassium and pH changes in a moist, soil-like environment, providing an integrated electronic readout. The sensors measure a range of parameters compatible with realistic soil conditions. The sensors' response can trigger the movement of the robotic root with a control algorithm inspired by the behavior of the plant root that determines the optimal path toward root growth, simulating the decision-making process of a plant. This nature-inspired technology may lead, in the future, to the realization of robotic devices with the potential for monitoring and exploring the soil autonomously.

JTD Keywords: Artificial intelligenc, Biomimetic, Chemical sensor, Ion-selective electrode (ise), Nitrate, Ph, Plant roots, Potassiu, Potassium, Robotics, Soil detection, Tropism

Candida albicans and Staphylococcus aureus have been co-isolated from several biofilm-associated diseases, including those related to medical devices. This association confers advantages to both microorganisms, resulting in detrimental effects on the host. To elucidate this phenomenon, the present study investigated colony changes derived from non-physical interactions between C. albicans and S. aureus. We performed proximity assays by confronting colonies of the yeast and the bacteria on agar plates at six different distances for 9-10 days. We found that colony variants of S. aureus originated progressively after prolonged exposure to C. albicans proximity, specifically in response to pH neutralization of the media by the fungi. The new phenotypes of S. aureus were more virulent in a Galleria mellonella larvae model compared to colonies grown without C. albicans influence. This event was associated with an upregulation of RNA III and agrA expression, suggesting a role for alpha-toxin. Our findings indicate that C. albicans enhances S. aureus virulence by inducing the formation of more aggressive colonies. This highlights the importance of understanding the intricate connection between environmental responses, virulence and, fitness in S. aureus pathogenesis.

JTD Keywords: Agr system, Aureus, Biofil, Expression, Galleria mellonella, Gene regulator agr, Interkingdom interactions, Pathogenicit, Polymicrobial interactions, Proximity assay, Synergistic effects

Over the last decade, 3D-printed porous calcium phosphates have emerged in the market for customized bone reconstruction. However, despite their excellent biological properties, the inherent brittleness is an obstacle that limits their clinical applications, as the scaffolds must withstand the surgical procedures and the mechanical stresses once implanted. Low-temperature self-hardening calcium phosphate inks offer unique possibilities to be reinforced with polymers, as they do not require high-temperature treatments. This study compares two routes for incorporating poly (lactic-co-glycolic acid) (PLGA) into 3D-printed calcium phosphate scaffolds: i) the use of a PLGA solution as a binder in an alpha-tricalcium phosphate self-hardening ink; ii) the infiltration of a PLGA solution into previously hardened 3D-printed calcium-deficient hydroxyapatite scaffolds. The influence of the added PLGA on the physical-chemical properties, mechanical performance and in vitro biological properties is assessed using a commercially available biomimetic calcium phosphate scaffold as a control. The addition of PLGA increases the plastic deformation capacity and the strength, both in compression and bending, and significantly improves the work of fracture of the scaffolds, up to an 8-fold in compression when PLGA is incorporated as a binder in the ink. Moreover, screwability tests demonstrate the enhanced fixability of the composite scaffolds in a knife-edge ridge indication with challenging fixation in the jaw. Importantly, the improvement of the mechanical properties by the addition of PLGA does not impair the good cytocompatibility of the material. Regarding the two routes studied, the PLGA incorporation in the ink is the best option in terms of overall improvement of the mechanical performance and osteogenic cell response.

JTD Keywords: Alkaline-phosphatase, B. composites, C. mechanical properties, Composite scaffold, D. apatite, Differentiation, E. biomedical application, In-vivo, Join, Regeneration

Bone regeneration often fails due to implants/grafts lacking vascular supply, causing necrotic tissue and poor integration. Microsurgical techniques are used to overcome this issue, allowing the graft to anastomose. These techniques have limitations, including severe patient morbidity and current research focuses on stimulating angiogenesis in situ using growth factors, presenting limitations, such as a lack of control and increased costs. Non-biological stimuli are necessary to promote angiogenesis for successful bone constructs. Recent studies have reported that bioactive glass dissolution products, such as calcium-releasing nanoparticles, stimulate hMSCs to promote angiogenesis and new vasculature. Moreover, the effect of 3D microporosity has also been reported to be important for vascularisation in vivo. . Therefore, we used room-temperature extrusion 3D printing with polylactic acid (PLA) and calcium phosphate (CaP) based glass scaffolds, focusing on geometry and solvent displacement for scaffold recovery. Combining both methods enabled reproducible control of 3D structure, porosity, and surface topography. Scaffolds maintained calcium ion release at physiological levels and supported human mesenchymal stem cell proliferation. Scaffolds stimulated the secretion of vascular endothelial growth factor (VEGF) after 3 days of culture. Subcutaneous implantation in vivo indicated good scaffold integration and blood vessel infiltration as early as one week after. PLA-CaP scaffolds showed increased vessel maturation 4 weeks after implantation without vascular regression. Results show PLA/CaP-based glass scaffolds, made via controlled 3D printing, support angiogenesis and vessel maturation, promising improved vascularization for bone regeneration.

JTD Keywords: 3d-printed porosity, Angiogenic growth-factors, Bioceramic scaffolds, Bone angiogenesis, Calcium phosphat, Calcium-phosphate, Cells, Composite, Extracellular calcium, Functional-role, In-vitro, Inorganic trace-elements, Matri, Polylactic acid, Regeneration

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

Biomaterial-associated infections (BAIs) pose significant challenges in modern medical technologies, being a major postoperative complication and leading cause of implant failure. These infections significantly risk patient health, resulting in prolonged hospitalization, increased morbidity and mortality rates, and elevated treatment expenses. This comprehensive review examines the mechanisms driving bacterial adhesion and biofilm formation on biomaterial surfaces, offering an in-depth analysis of current antimicrobial strategies for preventing BAIs. We explore antimicrobial-eluting biomaterials, contact-killing surfaces, and antifouling coatings, emphasizing the application of antifouling polymer brushes on medical devices. Recent advancements in multifunctional antimicrobial biomaterials, which integrate multiple mechanisms for superior protection against BAIs, are also discussed. By evaluating the advantages and limitations of these strategies, this review aims to guide the design and development of highly efficient and biocompatible antimicrobial biomaterials. We highlight potential design routes that facilitate the transition from laboratory research to clinical applications. Additionally, we provide insights into the potential of synthetic biology as a novel approach to combat antimicrobial resistance. This review aspires to inspire future research and innovation, ultimately improving patient outcomes and advancing medical device technology.

JTD Keywords: Animals, Anti-bacterial agents, Antifouling coatings, Antimicrobial peptide, Antimicrobial-eluting coatings, Antimicrobial‐eluting coatings, Bacterial adhesion, Bacterial biofilm formation, Biocompatible materials, Biofilms, Biomaterial-associated infections, Biomaterial‐associated infections, Contact killing coatings, Humans, In-vitr, Infused porous surfaces, Metal-oxide surfaces, Multifunctional antimicrobial coating, Multifunctional antimicrobial coatings, Poly(l-lysine)-g-poly(ethylene glycol) layers, Polymer brushes, Prosthesis-related infections, Silicone oil, Superhydrophobic surfaces, Urinary catheters

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

Hyperpolarized nuclear spins in molecules exhibit high magnetization that is unachievable by classical polarization techniques, making them widely used as sensors in physics, chemistry, and medicine. The state of a hyperpolarized material, however, is typically only studied indirectly and with partial destruction of magnetization, due to the nature of conventional detection by resonant-pickup NMR spectroscopy or imaging. Here, we establish atomic magnetometers with sub-pT sensitivity as an alternative modality to detect in real time the complex dynamics of hyperpolarized materials without disturbing or interrupting the magnetogenesis process. As an example of dynamics that are impossible to detect in real time by conventional means, we examine parahydrogen-induced H-1 and C-13 magnetization during adiabatic eigenbasis transformations at mu mu T-field avoided crossings. Continuous but nondestructive magnetometry reveals previously unseen spin dynamics, fidelity limits, and magnetization backaction effects. As a second example, we apply magnetometry to observe the chemical-exchange-driven C-13 hyperpolarization of [1-C-13]-pyruvate-the most important spin tracer for clinical metabolic imaging. The approach can be readily combined with other high-sensitivity magnetometers and is applicable to a broader range of general observation scenarios involving production, transport, and systems interaction of hyperpolarized compounds.

JTD Keywords: Adiabaticity, Dnp, Field, Hyperpolarization, Nmr, Nuclear spins, Optical magnetometry, Order, Para-hydrogen, Parahydrogen, Polarimetry, Polarization transfer

Mesenchymal stem cells (MSCs) interact with their surroundings via integrins, which link to the actin cytoskeleton and translate physical cues into biochemical signals through mechanotransduction. N-cadherins enable cell-cell communication and are also linked to the cytoskeleton. This crosstalk between integrins and cadherins modulates MSC mechanotransduction and fate. Here we show the role of this crosstalk in the mechanosensing of viscosity using supported lipid bilayers as substrates of varying viscosity. We functionalize these lipid bilayers with adhesion peptides for integrins (RGD) and N-cadherins (HAVDI), to demonstrate that integrins and cadherins compete for the actin cytoskeleton, leading to an altered MSC mechanosensing response. This response is characterised by a weaker integrin adhesion to the environment when cadherin ligation occurs. We model this competition via a modified molecular clutch model, which drives the integrin/cadherin crosstalk in response to surface viscosity, ultimately controlling MSC lineage commitment. The crosstalk between cell-cell and cell-matrix adhesions regulates stem cell fate. Here, the authors reveal a critical role for matrix viscosity in controlling this crosstalk, which they explain via a modified molecular clutch model.

JTD Keywords: Actin cytoskeleton, Adhesion, Animals, Arginyl-glycyl-aspartic acid, Cadherins, Cell adhesion, Cell communication, Fibronectin, Force transmission, Humans, Hydrogel, Integrins, Lipid bilayers, Matrix, Mechanotransduction, Mechanotransduction, cellular, Mesenchymal stem cells, Mobility, Oligopeptides, Osteogenic differentiation, Substrate stiffness, Vinculin, Viscosity

Alzheimer's disease (AD) is a progressive neurodegenerative disease, and it is currently the seventh leading cause of death worldwide. It is characterized by the extracellular aggregation of the amyloid beta-peptide (A beta) into oligomers and fibrils that cause synaptotoxicity and neuronal death. A beta exhibits a dual role in promoting oxidative stress and inflammation. This review aims to unravel the intricate connection between these processes and their contribution to AD progression. The review delves into oxidative stress in AD, focusing on the involvement of metals, mitochondrial dysfunction, and biomolecule oxidation. The distinct yet overlapping concept of nitro-oxidative stress is also discussed, detailing the roles of nitric oxide, mitochondrial perturbations, and their cumulative impact on A beta production and neurotoxicity. Inflammation is examined through astroglia and microglia function, elucidating their response to A beta and their contribution to oxidative stress within the AD brain. The blood-brain barrier and oligodendrocytes are also considered in the context of AD pathophysiology. We also review current diagnostic methodologies and emerging therapeutic strategies aimed at mitigating oxidative stress and inflammation, thereby offering potential treatments for halting or slowing AD progression. This comprehensive synthesis underscores the pivotal role of A beta in bridging oxidative stress and inflammation, advancing our understanding of AD and informing future research and treatment paradigms.

JTD Keywords: A-beta, Alzheimer's disease, Amyloid beta-peptide, Bace, Blood-brain-barrier, Central-nervous-system, Genome-wide association, Mitochondrial dysfunctio, Mouse model, Neurodegeneration, Nitric-oxide, Nitro-oxidative stress, Precursor protein, Reactive oxygen, Receptor-related protein-1

We present the use of an ultraporous permanently polarized hydroxyapatite (upp-HAp) catalyst for continuous and highly efficient production of formic acid (predominant) and acetic acid using wet CO2 (i.e. CO2 bubbled into liquid water) as a reagent. In all cases, reactions were conducted at temperatures ranging from 95 to 150 degrees C, using a CO2 constant flow of 100 mL s(-1), and without applying any external electric field and/or UV radiation. Herein, we study how to transfer such a catalytic system from batch to continuous reactions, focusing on the water supply (proton source): (1) wet CO2 or (2) liquid water in small amounts is introduced in the reactor. In general, the reduction of CO2 to formic acid predominates over the C-C bond formation reaction. On the other hand, when liquid water is added, two interesting outcomes are observed: (1) the yield of products is higher than in the first scenario (>2 mmol g(c)(-1)min(-1)) while the initial liquid water remains largely available due to the mild reaction temperature (95 degrees C); and (2) a high yield of ethanol (>0.5 mmol g(c)(-1)min(-1)) is observed at 120 degrees C, as a result of the increased efficiency of the C-C bond formation. Analysis of kinetic studies through temporal and temperature dependence shows that CO2 fixation is the rate limiting step, ruling out the competing effect of proton adsorption on the binding sites and confirming the crucial role of water. The activation energy for the CO2 fixation reaction has been determined to be 66 +/- 1 kJ mol(-1), which is within the range of conventional electro-assisted catalysts. Finally, mechanistic insights on the CO2 activation and role of the binding sites of upp-HAp are provided through isotopic-labeling ((CO2)-C-13) and near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) studies.

JTD Keywords: Butano, Challenges, Co2 reduction, Fuels, Hydrogenation, Mechanism, Nanomaterials, Noble-metal

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

The performance of single-chain polymeric nanoparticles (SCPNs) in biomedical applications highly depends on their conformational stability in cellular environments. Until now, such stability studies are limited to 2D cell culture models, which do not recapitulate the 3D tumor microenvironment well. Here, a microfluidic tumor-on-a-chip model is introduced that recreates the tumor milieu and allows in-depth insights into the diffusion, cellular uptake, and stability of SCPNs. The chip contains Matrigel/collagen-hyaluronic acid as extracellular matrix (ECM) models and is seeded with cancer cell MCF7 spheroids. With this 3D platform, it is assessed how the polymer's microstructure affects the SCPN's behavior when crossing the ECM, and evaluates SCPN internalization in 3D cancer cells. A library of SCPNs varying in microstructure is prepared. All SCPNs show efficient ECM penetration but their cellular uptake/stability behavior depends on the microstructure. Glucose-based nanoparticles display the highest spheroid uptake, followed by charged nanoparticles. Charged nanoparticles possess an open conformation while nanoparticles stabilized by internal hydrogen bonding retain a folded structure inside the tumor spheroids. The 3D microfluidic tumor-on-a-chip platform is an efficient tool to elucidate the interplay between polymer microstructure and SCPN's stability, a key factor for the rational design of nanoparticles for targeted biological applications.© 2024 The Authors. Small Methods published by Wiley-VCH GmbH.

JTD Keywords: 3d cancer cell uptake, Cancer cells, Cell culture, Cell uptake, Cellular uptake, Diseases, Ecm penetration, Extracellular matrices, Extracellular matrix penetration, Functional polymers, Hydrogen bonds, Medical applications, Microfluidics, Microstructure, Nanoparticles, Polymeric nanoparticles, Scpns, Single chains, Single-chain polymeric nanoparticle, Stability, Tumor-on-a-chip, Tumors

Following immunization, lymph nodes dynamically expand and contract. The mechanical and cellular changes enabling the early-stage expansion of lymph nodes have been characterized, yet the durability of such responses and their implications for adaptive immunity and vaccine efficacy are unknown. Here, by leveraging high-frequency ultrasound imaging of the lymph nodes of mice, we report more potent and persistent lymph-node expansion for animals immunized with a mesoporous silica vaccine incorporating a model antigen than for animals given bolus immunization or standard vaccine formulations such as alum, and that durable and robust lymph-node expansion was associated with vaccine efficacy and adaptive immunity for 100 days post-vaccination in a mouse model of melanoma. Immunization altered the mechanical and extracellular-matrix properties of the lymph nodes, drove antigen-dependent proliferation of immune and stromal cells, and altered the transcriptional features of dendritic cells and inflammatory monocytes. Strategies that robustly maintain lymph-node expansion may result in enhanced vaccination outcomes. Durable and robust lymph-node expansion is associated with the efficacy of therapeutic vaccination, as shown in mice immunized via a biomaterial-based vaccine.

JTD Keywords: Antigen, Ccr2, Cell responses, Initiation, Vivo

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

This study investigates the synthesis and optimization of nanobots (NBs) loaded with pDNA using the layer-by-layer (LBL) method and explores the impact of their collective motion on the transfection efficiency. NBs consist of biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) nanoparticles and are powered by the urease enzyme, enabling autonomous movement and collective swarming behavior. In vitro experiments were conducted to validate the delivery efficiency of fluorescently labeled NBs, using two-dimensional (2D) and three-dimensional (3D) cell models: murine urothelial carcinoma cell line (MB49) and spheroids from human urothelial bladder cancer cells (RT4). Swarms of pDNA-loaded NBs showed enhancements of 2.2- to 2.6-fold in delivery efficiency and 6.8- to 8.1-fold in material delivered compared to inhibited particles (inhibited enzyme) and the absence of fuel in a 2D cell culture. Additionally, efficient intracellular delivery of pDNA was demonstrated in both cell models by quantifying and visualizing the expression of eGFP. Swarms of NBs exhibited a >5-fold enhancement in transfection efficiency compared to the absence of fuel in a 2D culture, even surpassing the Lipofectamine 3000 commercial transfection agent (cationic lipid-mediated transfection). Swarms also demonstrated up to a 3.2-fold enhancement in the amount of material delivered in 3D spheroids compared to the absence of fuel. The successful transfection of 2D and 3D cell cultures using swarms of LBL PLGA NBs holds great potential for nucleic acid delivery in the context of bladder treatments.

JTD Keywords: Animals, Barrier, Cell line, tumor, Dna, Drug delivery, Drug-delivery, Enzyme catalysis, Gene delivery, Gene transfer techniques, Humans, Lactic acid, Mice, Nanobots, Nanoparticles, Pdna, Plasmids, Polyglycolic acid, Polylactic acid-polyglycolic acid copolymer, Swarming, Transfectio, Transfection, Urease, Urinary bladder neoplasms

Hydrogels with cell adhesive moieties stand out as promising materials to enhance tissue healing and regeneration. Nonetheless, bacterial infections of the implants represent an unmet major concern. In the present work, we developed an alginate hydrogel modified with a multifunctional peptide containing the RGD cell adhesive motif in combination with an antibacterial peptide derived from the 1-11 region of lactoferrin (LF). The RGD-LF branched peptide was successfully anchored to the alginate backbone by carbodiimide chemistry, as demonstrated by 1H NMR and fluorescence measurements. The functionalized hydrogel presented desirable physicochemical properties (porosity, swelling and rheological behavior) to develop biomaterials for tissue engineering. The viability of mesenchymal stem cells (MSCs) on the peptide-functionalized hydrogels was excellent, with values higher than 85 % at day 1, and higher than 95 % after 14 days in culture. Moreover, the biological characterization demonstrated the ability of the hydrogels to significantly enhance ALP activity of MSCs as well as to decrease bacterial colonization of both Gram-positive and Gram-negative models. Such results prove the potential of the functionalized hydrogels as novel biomaterials for tissue engineering, simultaneously displaying cell adhesive activity and the capacity to prevent bacterial contamination, a dual bioactivity commonly not found for these types of hydrogels. In this work we report on the functionalization of an alginate hydrogel with a tailor-made multifunctional peptide containing the cell adhesive RGD motif and the LF1-11 antibacterial peptide. Such novel multifunctional biomaterial ensures the viability of human mesenchymal stem cells, enhances ALP activity and decreases bacterial infections of both Gram-positive and Gram-negative models. image

JTD Keywords: Alginate hydrogel, Alginates, Anti-bacterial agents, Antimicrobial peptid, Antimicrobial peptide, Antimicrobial peptides, Arginyl-glycyl-aspartic acid, Biocompatible materials, Biofunctionalization, Bone, Cell adhesion, Cell survival, Composite hydrogels, Cross-linking, Hlf1-11 peptide, Human lactoferrin, Humans, Hydrogels, Immobilization, Mesenchymal stem cells, Multifunctional peptide, Oligopeptides, Peptides, Physical-properties, Scaffolds, Surfac, Tissue engineering

The blood-brain barrier (BBB) tightly regulates substance transport between the bloodstream and the brain. Models for the study of the physiological processes affecting the BBB, as well as predicting the permeability of therapeutic substances for neurological and neurovascular pathologies, are highly desirable. Existing models, such as Transwell utilizing-models, do not mimic the extracellular environment of the BBB with their stiff, semipermeable, non-biodegradable membranes. To help overcome this, we engineered electrospun membranes from poly L-lactic acid in combination with a nanometric coating of poly(ethyl acrylate) (PEA) that drives fibrillogenesis of fibronectin, facilitating the synergistic presentation of both growth factors and integrin binding sites. Compared to commercial semi-porous membranes, these membranes significantly improve the expression of BBB-related proteins in brain endothelial cells. PEA-coated membranes in combination with different growth factors and extracellular protein coatings reveal nerve growth factor (NGF) and fibroblast growth factor (FGF-2) caused formation of better barriers in vitro. This BBB model offers a robust platform for studying key biochemical factors influencing barrier formation that marries the simplicity of the Transwell model with the highly tunable electrospun PEA-fibronectin membranes. This enables the generation of high-throughput drug permeability models without the need of complicated co-culture conditions. The blood-brain barrier (BBB) tightly regulates substance transport between the bloodstream and the brain. Here a simple model of the BBB that allows culture of endothelial cells on growth-factor functionalised membranes is introduced. This novel in vitro model of the BBB offers a robust platform for studying key barriergenic biochemical factors influencing barrier formation without the use of the complicated co-culture conditions. image

JTD Keywords: Animals, Bbb, Blood-brain barrier, Densit, Differentiation, Ecm, Electrospinning, Endothelial cells, Endothelial-cell lines, Expression, Fiber diameter, Fibroblast-growth-factor, Growth factors, Humans, In vitro mode, In vitro model, Membranes, artificial, Models, biological, Morphology, Permeability, Poly(l-lactic acid), Poly(lactide), Polyesters, Proteins

The precise mechanisms underlying the cellular response to static electric cues remain unclear, limiting the design and development of biomaterials that utilize this parameter to enhance specific biological behaviours. To gather information on this matter we have explored the interaction of collagen type-I, the most abundant mammalian extracellular protein, with poly(vinylidene fluoride) (PVDF), an electroactive polymer with great potential for tissue engineering applications. Our results reveal significant differences in collagen affinity, conformation, and interaction strength depending on the electric charge of the PVDF surface, which subsequently affects the behaviour of mesenchymal stem cells seeded on them. These findings highlight the importance of surface charge in the establishment of the material-protein interface and ultimately in the biological response to the material. The development of new tissue engineering strategies relies heavily on the understanding of how biomaterials interact with biological tissues. Although several factors drive this process and their driving principles have been identified, the relevance and mechanism by which the surface potential influences cell behaviour is still unknown. In our study, we investigate the interaction between collagen, the most abundant component of the extracellular matrix, and poly(vinylidene fluoride) with varying surface charges. Our findings reveal substantial variations in the binding forces, structure and adhesion of collagen on the different surfaces, which collectively explain the differential cellular responses. By exposing these differences, our research fills a critical knowledge gap and paves the way for innovations in material design for advanced tissue regeneration strategies. (c) 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

JTD Keywords: Adhesion, Atomic-force microscope, Biomaterials, Collagen, Collagen fibril, Electroactive material, Energ, Nanofibers, Osteogenic differentiation, Polyvinylidene fluoride, Pvdf, Stimuli, Surface charge, Surface coating, Systems

To date, strategies aiming to modulate cell to extracellular matrix (ECM) interactions during organoid derivation remain largely unexplored. Here renal decellularized ECM (dECM) hydrogels are fabricated from porcine and human renal cortex as biomaterials to enrich cell-to-ECM crosstalk during the onset of kidney organoid differentiation from human pluripotent stem cells (hPSCs). Renal dECM-derived hydrogels are used in combination with hPSC-derived renal progenitor cells to define new approaches for 2D and 3D kidney organoid differentiation, demonstrating that in the presence of these biomaterials the resulting kidney organoids exhibit renal differentiation features and the formation of an endogenous vascular component. Based on these observations, a new method to produce kidney organoids with vascular-like structures is achieved through the assembly of hPSC-derived endothelial-like organoids with kidney organoids in 3D. Major readouts of kidney differentiation and renal cell morphology are assessed exploiting these culture platforms as new models of nephrogenesis. Overall, this work shows that exploiting cell-to-ECM interactions during the onset of kidney differentiation from hPSCs facilitates and optimizes current approaches for kidney organoid derivation thereby increasing the utility of these unique cell culture platforms for personalized medicine. Natural hydrogels derived from decellularized porcine or human kidney tissues are used to generate kidney organoids from human pluripotent stem cells, resulting in the enrichment of organoids' endogenous vascular component and improved renal differentiation. Exploiting the autonomous capacity of kidney organoids to exhibit endogenous vascularization in combination with these biomaterials, a novel approach is established to generate endothelial-kidney assembloids showing vascular-like structures. image

JTD Keywords: Angiogenesis, Animals, Assembloids, Biocompatible materials, Cell differentiation, Decellularized extracellular matrix, Extracellular matrix, Extracellular matrix-derived hydrogels, Extracellular matrix‐derived hydrogels, Extracellular-matrix, Human pluripotent stem cells, Humans, Hydrogels, Kidney, Kidney organoids, Neovascularization, physiologic, Organoids, Pluripotent stem cells, Pluripotent stem-cells, Swine, Tissu, Tissue engineering, Vascularizatio, Vascularization

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

The use of transdermal delivery for nucleic acid administration is an interesting approach to overcoming limitations of systemic administration routes, such as first-pass effects, the painful needle injection, or their poor biodistribution. Thus, the use of a microneedle-based patch could represent a turning point for nucleic acid delivery, thanks to the possibility of self-administration of the actives in a painless and easy procedure. However, the design of transdermal systems with a higher degree of precision release is a clear need that has not been fully resolved. Committed to tackling this challenge, we present here a microneedle patch that involves a smart delivery system supported by the well-established ability of boronic acid to interact with carbohydrates in a pH-dependent manner. This system builds up a multilayer structure over a solid microneedle platform whose surface has been modified to immobilize glucosamine units that are able to interact with an oligopeptide-end terminated poly(beta-aminoester) that presents a 4-carboxy-3-fluorophenylboronic acid (Bor-pBAE). Thus, sequential layers of the Bor-pBAE and plasmid DNA have been assembled, thanks to the ability of the polymer to interact with the nucleic acid at a basic pH and then gradually release the plasmid under two different conditions of pH (the physiological pH = 7.4 and the acidic pH = 5.1). We set up the design and implementation of this first proof of concept while demonstrating microneedles' safety and functionality. Additionally, we have shown the efficacy of the construct to express the encoded genes in model cell lines. In conclusion, we have established the basis to confirm that this generation of borylated poly(beta-aminoesters) holds great promise as a transdermal local nucleic acid delivery system.

JTD Keywords: Balance, Borylated poly(beta-aminoester), Drug-delivery, Ester)s, Gene deliver, Gene delivery, Microneedles, Multilayered coating, Polyelectrolytes, Release, Ski, Surface-charge

Antimicrobial resistance (AMR) poses a significant threat to human health. Although vaccines have been developed to combat AMR, it has proven challenging to associate specific vaccine antigens with AMR. Bacterial plasmids play a crucial role in the transmission of AMR. Our recent research has identified a group of bacterial plasmids (specifically, IncHI plasmids) that encode large molecular mass proteins containing bacterial immunoglobulin-like domains. These proteins are found on the external surface of the bacterial cells, such as in the flagella or conjugative pili. In this study, we show that these proteins are antigenic and can protect mice from infection caused by an AMR Salmonella strain harboring one of these plasmids. Furthermore, we successfully generated nanobodies targeting these proteins, that were shown to interfere with the conjugative transfer of IncHI plasmids. Considering that these proteins are also encoded in other groups of plasmids, such as IncA/C and IncP2, targeting them could be a valuable strategy in combating AMR infections caused by bacteria harboring different groups of AMR plasmids. Since the selected antigens are directly linked to AMR itself, the protective effect extends beyond specific microorganisms to include all those carrying the corresponding resistance plasmids.

JTD Keywords: Antibodies, Beta-lactamase, Cell, Enterica, Escherichia-coli, Expression, Genes, Infection, Intimin, Mous, Mutational analysis, Pcr, Salmonella, Var typhimurium

Only 30% of embryos from in vitro fertilized oocytes successfully implant and develop to term, leading to repeated transfer cycles. To reduce time-to-pregnancy and stress for patients, there is a need for a diagnostic tool to better select embryos and oocytes based on their physiology. The current standard employs brightfield imaging, which provides limited physiological information. Here, we introduce METAPHOR: Metabolic Evaluation through Phasor-based Hyperspectral Imaging and Organelle Recognition. This non-invasive, label-free imaging method combines two-photon illumination and AI to deliver the metabolic profile of embryos and oocytes based on intrinsic autofluorescence signals. We used it to classify i) mouse blastocysts cultured under standard conditions or with depletion of selected metabolites (glucose, pyruvate, lactate); and ii) oocytes from young and old mouse females, or in vitro-aged oocytes. The imaging process was safe for blastocysts and oocytes. The METAPHOR classification of control vs. metabolites-depleted embryos reached an area under the ROC curve (AUC) of 93.7%, compared to 51% achieved for human grading using brightfield imaging. The binary classification of young vs. old/in vitro-aged oocytes and their blastulation prediction using METAPHOR reached an AUC of 96.2% and 82.2%, respectively. Finally, organelle recognition and segmentation based on the flavin adenine dinucleotide signal revealed that quantification of mitochondria size and distribution can be used as a biomarker to classify oocytes and embryos. The performance and safety of the method highlight the accuracy of noninvasive metabolic imaging as a complementary approach to evaluate oocytes and embryos based on their physiology.

JTD Keywords: Ai, Consumption, Culture, Embryo development, Fluorescence, Hyperspectral imagin, Implantation, In vitro fertilization, Infertility, Label-free imaging, Microscopy, Morphokinetics, Oxygen concentrations, Selectio, Time-lapse

There has been a huge demand for engineered skin tissues in the realms of both in vitro and in vivo applications. Selecting the right material scaffold is a critical consideration in making engineered skin tissues, since it should possess a good balance between elasticity and mechanical stability while promoting an adequate cell microenvironment to support both the dermal and the epidermal compartments of skin tissue. In this study, 3D-bioprinted norbornene-pullulan photocrosslinkable hydrogels were utilized as alternative scaffolds to produce epithelized dermal skin models. By employing visible light, 2.5 mm3 cell-laden hydrogels could be printed in 10 s. The thiol-ene photocrosslinking chemistry employed in this work enabled the formation of a well-defined extracellular matrix with orthogonal crosslinks, where encapsulated fibroblasts maintained high cellular viability rates. Through this method, an epidermal layer could be grown on top of the fibroblasts. The coexistence and interaction of human fibroblasts and keratinocytes were visualized by determining the expression of specific markers. This approach represents a promising starting point for the development of photocrosslinkable hydrogel-based human skin constructs by using thiol-ene norbornene chemistry, paving the way toward manufacture of complex in vitro models of human tissues.

JTD Keywords: Cells, Collagen, Differentiation, Gel, In-vitro, Light-based 3d bioprintin, Matrix, Mechanical-properties, Models, Photocrosslinkable hydrogels, Pullulan, Skin models

Graphene and graphene oxide (GO), due to their unique chemical and physical properties, possess biochemical characteristics that can trigger intercellular signals promoting tissue regeneration. Clinical applications of thin GO-derived sheets have inspired the development of various tissue regeneration and repair approaches. In this study, we demonstrate that ultrathin sheets of plasma-functionalized and reduced GO, with the oxygen content ranging from 3.2 % to 22 % and the nitrogen content from 0 % to 8.3 %, retain their essential mechanical and molecular integrity, and exhibit robust potential for regenerating bone tissue and blood vessels across multiple cellular and animal models. Initially, we observed the growth of blood vessels and bone tissue in vitro using these functionalized GO sheets on human adipose-derived mesenchymal stem cells and umbilical vein endothelial cells. Remarkably, our study indicates a 2.5-fold increase in mineralization and two-fold increase in tubule formation even in media lacking osteogenic and angiogenic supplements. Subsequently, we observed the initiation, conduction, and formation of bone and blood vessels in a rat tibial osteotomy model, evident from a marked 4-fold increase in the volume of low radio-opacity bone tissue and a significant elevation in connectivity density, all without the use of stem cells or growth factors. Finally, we validated these findings in a mouse critical-size calvarial defect model (33 % higher healing rate) and a rat skin lesion model (up to 2.5-fold increase in the number of blood vessels, and 35 % increase in blood vessels diameter). This study elucidates the proosteogenic and pro-angiogenic properties of both pristine and plasma-treated GO ultrathin films. These properties suggest their significant potential for clinical applications, and as valuable biomaterials for investigating fundamental aspects of bone and blood vessel regeneration.

JTD Keywords: Adhesion, Angiogenesis, Biocompatibilit, Bone regeneratio, Coatings, Fibronectin, Graphene oxide, Growth, Mesenchymal stem-cells, Osteoblast, Osteogenic differentiation, Plasma treatment, Protein, Tissue regeneration

[No abstract available]

JTD Keywords: Alpha synuclein, Animal cell, Article, Astrocyte, Brain blood flow, Capillary endothelial cell, Cardiovascular system, Cell interaction, Coculture, Degenerative disease, Differential expression analysis, Endothelium cell, Entactin, Extracellular matrix, Fibronectin, Gene expression, Human, Human cell, Huntington chorea, Hydroxyapatite, In vitro study, Induced pluripotent stem cell, Laminin, Macrophage, Maturity, Microglia, Nervous system, Nervous system inflammation, Neuroprotection, Neurotoxicity, Nonhuman, Parkinson disease, Pericyte, Perivascular space, Personalized medicine, Shear stress, Smooth muscle cell, Three dimensional printing

Biological barriers present a significant obstacle to treatment, especially when drugs are administered locally to increase their concentrations at the target site while minimizing unintended off-target effects. Among these barriers, mucus presents a challenge, as it serves as a protective layer in the respiratory, urogenital, and gastrointestinal tracts. Its role is to shield the underlying epithelial cells from pathogens and toxic compounds but also impedes the efficient delivery of drugs. Despite the exploration of mucolytic agents to improve drug delivery, overcoming this protective barrier remains a significant hurdle. In our study, we investigate an alternative approach involving the use of catalase-powered nanobots. We use an in vitro model that simulates intestinal mucus secretion to demonstrate the dual functionality of our nanobots. This includes their ability to disrupt mucus, which we confirmed through in vitro and ex vivo validation, as well as their self-propulsion to overcome the mucus barrier, resulting in a 60-fold increase compared with passive nanoparticles. Therefore, our findings highlight the potential utility of catalase-powered nanobots as carriers for therapeutic agents since they could enhance drug delivery efficiency by penetrating the mucus barrier.

JTD Keywords: Biological barrier, Biological barriers, Drug-delivery, Growth, Hydrogen-peroxide, Muci, Mucus, Nanobots, Nanomedicine, Nanomotors, Transport

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

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

Bone regeneration remains a major clinical challenge, especially when infection necessitates prolonged antibiotic treatment. This study presents a membrane composed of self-assembled and interpenetrating GL13K, an antimicrobial peptide (AMP) derived from a salivary protein, in a collagen membrane for antimicrobial activity and enhanced bone regeneration. Commercially available collagen membranes were immersed in GL13K solution, and self-assembly was initiated by raising the solution pH to synthesize the multifunctional membrane called COL-GL. COL-GL was composed of interpenetrating large collagen fibers and short GL13K nanofibrils, which increased hydrophobicity, reduced biodegradation from collagenase, and stiffened the matrix compared to control collagen membranes. Incorporation of GL13K led to antimicrobial and anti-fouling activity against early oral surface colonizer Streptococcus gordonii while not affecting fibroblast cytocompatibility or pre-osteoblast osteogenic differentiation. GL13K in solution also reduced macrophage inflammatory cytokine expression and increased pro-healing cytokine expression. Bone formation in a rat calvarial model was accelerated at eight weeks with COL-GL compared to the gold-standard collagen membrane based on microcomputed tomography and histology. Interpenetration of GL13K within collagen sidesteps challenges with antimicrobial coatings on bone regeneration scaffolds while increasing bone regeneration. This strength makes COL-GL a promising approach to reduce post-surgical infections and aid bone regeneration in dental and orthopedic applications. Statement of significance: The COL-GL membrane, incorporating the antimicrobial peptide GL13K within a collagen membrane, signifies a noteworthy breakthrough in bone regeneration strategies for dental and orthopedic applications. By integrating self-assembled GL13K nanofibers into the membrane, this study successfully addresses the challenges associated with antimicrobial coatings, exhibiting improved antimicrobial and antifouling activity while preserving compatibility with fibroblasts and pre-osteoblasts. The accelerated bone formation observed in a rat calvarial model emphasizes the potential of this innovative approach to minimize postsurgical infections and enhance bone regeneration outcomes. As a promising alternative for future therapeutic interventions, this material tackles the clinical challenges of extended antibiotic treatments and antibiotic resistance in bone regeneration scenarios.

JTD Keywords: Antibacterial, Antimicrobial, Antimicrobial peptide, Bone regeneration, Coatings, Collagen, Gl13k, Growth-factor delivery, Infection, Release, Scaffolds, Self -assembly, Strategies, Titanium

The extracellular matrix (ECM) is a dynamic and complex network of proteins and molecules that surrounds cells and tissues in the nervous system and orchestrates a myriad of biological functions. This review carefully examines the diverse interactions between cells and the ECM, as well as the transformative chemical and physical changes that the ECM undergoes during neural development, aging, and disease. These transformations play a pivotal role in shaping tissue morphogenesis and neural activity, thereby influencing the functionality of the central nervous system (CNS). In our comprehensive review, we describe the diverse behaviors of the CNS ECM in different physiological and pathological scenarios and explore the unique properties that make ECM-based strategies attractive for CNS repair and regeneration. Addressing the challenges of scalability, variability, and integration with host tissues, we review how advanced natural, synthetic, and combinatorial matrix approaches enhance biocompatibility, mechanical properties, and functional recovery. Overall, this review highlights the potential of decellularized ECM as a powerful tool for CNS modeling and regenerative purposes and sets the stage for future research in this exciting field. This article is categorized under: Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease Implantable Materials and Surgical Technologies > Nanomaterials and Implants

JTD Keywords: Amyotrophic-lateral-sclerosis, Biologic scaffold, Central nervous system, Central-nervous-system, Chondroitin sulfate proteoglycans, Decellularization, Extracellular matrix, Motor-neurons, Neural disorders, Neural regeneratio, Perineuronal nets, Self-healing hydrogel, Spinal-cord-injury, Stem-cell, Vascular basement-membrane

Biofabrication of three-dimensional (3D) cultures through the 3D Bioprinting technique opens new perspectives and applications of cell-laden hydrogels. However, to continue with the progress, new BioInks with specific properties must be carefully designed. In this study, we report the synthesis and 3D Bioprinting of an electroconductive BioInk made of gelatin/fibrinogen hydrogel, C2C12 mouse myoblast and 5% w/w of conductive poly (3,4-ethylenedioxythiophene) nanoparticles (PEDOT NPs). The influence of PEDOT NPs, incorporated in the cellladen BioInk, not only showed a positive effect in cells viability, differentiation and myotube functionalities, also allowed the printed constructs to behaved as BioCapacitors. Such devices were able to electrochemically store a significant amount of energy (0.5 mF/cm2), enough to self-stimulate as BioActuator, with typical contractions ranging from 27 to 38 mu N, during nearly 50 min. The biofabrication of 3D constructs with the proposed electroconductive BioInk could lead to new devices for tissue engineering, biohybrid robotics or bioelectronics.

JTD Keywords: 3d bioprinting, Animal, Animals, Bioactuator, Bioactuators, Biocapacitor, Biofabrication, Bioprinting, Biosensing techniques, C2c12 myoblasts, Cells, Chemistry, Electric conductivity, Electroconductive, Electroconductive bioink, Ethylenedioxythiophenes, Genetic procedures, Hydrogel, Hydrogels, Mice, Mouse, Pedot nps, Pedot nps,3d bioprinting,electroconductive bioink,bioactuator,biocapacito, Poly (3,4-ethylenedioxythiophene) nanoparticle, Printing, three-dimensional, Procedures, Skeletal-muscle,cytotoxicity,polymer, Synthesis (chemical), Three dimensional printing, Tissue engineering, Tissue scaffolds

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

Cholesterol, a crucial component of cell membranes, influences various biological processes, including membrane trafficking, signal transduction, and host-pathogen interactions. Disruptions in cholesterol homeostasis have been linked to congenital and acquired conditions, including neurodegenerative disorders such as Alzheimer's disease (AD). Previous research from our group has demonstrated that herpes simplex virus type I (HSV-1) induces an AD-like phenotype in several cell models of infection. This study explores the interplay between cholesterol and HSV-1-induced neurodegeneration. The impact of cholesterol was determined by modulating its levels with methyl-beta-cyclodextrin (M beta CD) using the neuroblastoma cell lines SK-N-MC and N2a. We have found that HSV-1 infection triggers the intracellular accumulation of cholesterol in structures resembling endolysosomal/autophagic compartments, a process reversible upon M beta CD treatment. Moreover, M beta CD exhibits inhibitory effects at various stages of HSV-1 infection, underscoring the importance of cellular cholesterol levels, not only in the viral entry process but also in subsequent post-entry stages. M beta CD also alleviated several features of AD-like neurodegeneration induced by viral infection, including lysosomal impairment and intracellular accumulation of amyloid-beta peptide (A beta) and phosphorylated tau. In conclusion, these findings highlight the connection between cholesterol, neurodegeneration, and HSV-1 infection, providing valuable insights into the underlying mechanisms of AD.

JTD Keywords: Alzheimer's disease, Arterial cells, Beta-amyloid, Cholesterol, Hsv-1, Hyperphosphorylated ta, Infection, Lysosomal alterations, Methyl-beta-cyclodextrin, Neuroblastoma cells, Neurodegeneration, Syste

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

Steroid myopathy is a clinically challenging condition exacerbated by prolonged corticosteroid use or adrenal tumors. In this study, we engineered a functional three-dimensional (3D) in vitro skeletal muscle model to investigate steroid myopathy. By subjecting our bioengineered muscle tissues to dexamethasone treatment, we reproduced the molecular and functional aspects of this disease. Dexamethasone caused a substantial reduction in muscle force, myotube diameter and induced fatigue. We observed nuclear translocation of the glucocorticoid receptor (GCR) and activation of the ubiquitin-proteasome system within our model, suggesting their coordinated role in muscle atrophy. We then examined the therapeutic potential of taurine in our 3D model for steroid myopathy. Our findings revealed an upregulation of phosphorylated AKT by taurine, effectively countering the hyperactivation of the ubiquitin- proteasomal pathway. Importantly, we demonstrate that discontinuing corticosteroid treatment was insufficient to restore muscle mass and function. Taurine treatment, when administered concurrently with corticosteroids, notably enhanced contractile strength and protein turnover by upregulating the AKT-mTOR axis. Our model not only identifies a promising therapeutic target, but also suggests combinatorial treatment that may benefit individuals undergoing corticosteroid treatment or those diagnosed with adrenal tumors.

JTD Keywords: 3d bioengineered skeletal muscle tissues, Adrenal cortex hormones, Atroph, Colocalization, Corticosteroids, Dexamethasone, Glucocorticoid-receptor, Humans, Mechanisms, Models, biological, Mtor protein, human, Muscle contraction, Muscle fibers, skeletal, Muscle strength, Muscle, skeletal, Muscular diseases, Organ size, Phosphorylation, Proteasome endopeptidase complex, Proto-oncogene proteins c-akt, Receptors, glucocorticoid, Signal transduction, Skeletal-muscle, Steroid myopathy, Steroids, Supplementation, Taurin, Taurine, Tor serine-threonine kinases, Ubiquitin

Multiplexed assays of variant effect (MAVEs) have emerged as a powerful approach for interrogating thousands of genetic variants in a single experiment. The flexibility and widespread adoption of these techniques across diverse disciplines have led to a heterogeneous mix of data formats and descriptions, which complicates the downstream use of the resulting datasets. To address these issues and promote reproducibility and reuse of MAVE data, we define a set of minimum information standards for MAVE data and metadata and outline a controlled vocabulary aligned with established biomedical ontologies for describing these experimental designs.

JTD Keywords: Deep mutational scanning, Dms, Genetic variants, Genomics, Mave, Multiplexed assays of variant effect, Standards

Here, we report DNA-based synthetic nanostructures decorated with enzymes (hereafter referred to as DNA-enzyme swimmers) that self-propel by converting the enzymatic substrate to the product in solution. The DNA-enzyme swimmers are obtained from tubular DNA structures that self-assemble spontaneously by the hybridization of DNA tiles. We functionalize these DNA structures with two different enzymes, urease and catalase, and show that they exhibit concentration-dependent movement and enhanced diffusion upon addition of the enzymatic substrate (i.e., urea and H2O2). To demonstrate the programmability of such DNA-based swimmers, we also engineer DNA strands that displace the enzyme from the DNA scaffold, thus acting as molecular brakes on the DNA swimmers. These results serve as a first proof of principle for the development of synthetic DNA-based enzyme-powered swimmers that can self-propel in fluids.

JTD Keywords: Biocatalysis, Catalase, Design, Dna, Hydrogen peroxide, Motor, Nanostructures, Shapes, Urease

Introduction: Aging induces functional and structural changes in the lung, characterized by a decline in elasticity and diminished pulmonary remodeling and regenerative capacity. Emerging evidence suggests that most biomechanical alterations in the lung result from changes in the composition of the lung extracellular matrix (ECM), potentially modulating the behavior of pulmonary cells and increasing the susceptibility to chronic lung diseases. Therefore, it is crucial to investigate the mechanical properties of the aged lung. This study aims to assess the mechanical alterations in the lung ECM due to aging at both residual (RV) and functional (FV) lung volumes and to evaluate their effects on the survival and proliferation of mesenchymal stromal cells (MSCs).Methods: The lungs from young (4-6-month-old) and aged (20-24-month-old) mice were inflated with optimal cutting temperature compound to reach FV or non-inflated (RV). ECM proteins laminin, collagen I and fibronectin were quantified by immunofluorescence and the mechanical properties of the decellularized lung sections were assessed using atomic force microscopy. To investigate whether changes in ECM composition by aging and/or mechanical properties at RV and FV volumes affects MSCs, their viability and proliferation were evaluated after 72 h.Results: Laminin presence was significantly reduced in aged mice compared to young mice, while fibronectin and collagen I were significantly increased in aged mice. In RV conditions, the acellular lungs from aged mice were significantly softer than from young mice. By contrast, in FV conditions, the aged lung ECM becomes stiffer than that of in young mice, revealing that strain hardening significantly depends on aging. Results after MSCs recellularization showed similar viability and proliferation rate in all conditions.Discussion: This data strongly suggests that biomechanical measurements, especially in aging models, should be carried out in physiomimetic conditions rather than following the conventional non-inflated lung (RV) approach. The use of decellularized lung scaffolds from aged and/or other lung disease murine/human models at physiomimetic conditions will help to better understand the potential role of mechanotransduction on the susceptibility and progression of chronic lung diseases, lung regeneration and cancer.

JTD Keywords: Age, Aging, Biomechanical properties, Collagen, Decellularization, Elasti, Fibrosis, Lung extracellular matrix, Lung volume, Mechanics, Mesenchymal stromal cell, Stiffness

The problems associated with the drugs currently used to treat leishmaniasis, including resistance, toxicity, and the high cost of some formulations, call for the urgent identification of new therapeutic agents with novel modes of action. The aggregated protein dye YAT2150 has been found to be a potent antileishmanial compound, with a half-maximal inhibitory concentration (IC50) of approximately 0.5 mu M against promastigote and amastigote stages of Leishmania infantum. The encapsulation in liposomes of YAT2150 significantly improved its in vitro IC50 to 0.37 and 0.19 mu M in promastigotes and amastigotes, respectively, and increased the half-maximal cytotoxic concentration in human umbilical vein endothelial cells to >50 mu M. YAT2150 became strongly fluorescent when binding intracellular protein deposits in Leishmania cells. This fluorescence pattern aligns with the proposed mode of action of this drug in the malaria parasite Plasmodium falciparum, the inhibition of protein aggregation. In Leishmania major, YAT2150 rapidly reduced ATP levels, suggesting an alternative antileishmanial mechanism. To the best of our knowledge, this first-in-class compound is the only one described so far having significant activity against both Plasmodium and Leishmania, thus being a potential drug for the treatment of co-infections of both parasites.

JTD Keywords: Animal, Animals, Antileishmanial drugs, Antiprotozoal agent, Antiprotozoal agents, Axenic amastigotes, Colocalization, Differentiation, Discovery, Endothelial cells, Endothelium cell, Human, Humans, Identification, Leishmania, Leishmania infantum, Leishmaniasis, Parasite, Parasites, Protein aggregation, Yat2150, Yeast

Simple Summary Neuroblastoma (NB), a prevalent childhood cancer, presents challenges in treatment due to its cellular diversity and the presence of tumor-derived endothelial cells (TECs) associated with chemoresistance. We lack specific biomarkers for TECs, hindering effective therapies. We developed a stiffness-based in vitro platform simulating arterial and venous conditions to address this gap. Notably, adrenergic NB cells transdifferentiated into TECs where there was an arterial-like stiffness, while mesenchymal cells did not. This platform facilitated the identification of Globotriaosylceramide (GB3) as a novel TEC biomarker. Moreover, we harnessed Shiga toxin-functionalized nanoparticles for the specific targeting of GB3-positive cells, showing promise for future therapeutic strategies. Our study provides insights into NB heterogeneity, offers a predictive tool for assessing aggressiveness, and introduces potential targets for precision therapies.Abstract Neuroblastoma (NB) is a childhood cancer in sympathetic nervous system cells. NB exhibits cellular heterogeneity, with adrenergic and mesenchymal states displaying distinct tumorigenic potentials. NB is highly vascularized, and blood vessels can form through various mechanisms, including endothelial transdifferentiation, leading to the development of tumor-derived endothelial cells (TECs) associated with chemoresistance. We lack specific biomarkers for TECs. Therefore, identifying new TEC biomarkers is vital for effective NB therapies. A stiffness-based platform simulating human arterial and venous stiffness was developed to study NB TECs in vitro. Adrenergic cells cultured on arterial-like stiffness transdifferentiated into TECs, while mesenchymal state cells did not. The TECs derived from adrenergic cells served as a model to explore new biomarkers, with a particular focus on GB3, a glycosphingolipid receptor implicated in angiogenesis, metastasis, and drug resistance. Notably, the TECs unequivocally expressed GB3, validating its novelty as a marker. To explore targeted therapeutic interventions, nanoparticles functionalized with the non-toxic subunit B of the Shiga toxin were generated, because they demonstrated a robust affinity for GB3-positive cells. Our results demonstrate the value of the stiffness-based platform as a predictive tool for assessing NB aggressiveness, the discovery of new biomarkers, and the evaluation of the effectiveness of targeted therapeutic strategies.

JTD Keywords: Alternative vasculature, Angiogenesis, Cells, Differentiation, Gb3, Neuroblastoma, Origin, Tumor-derived endothelial cells

Malaria, caused by different species of protists of the genus Plasmodium, remains among the most common causes of death due to parasitic diseases worldwide, mainly for children aged under 5. One of the main obstacles to malaria eradication is the speed with which the pathogen evolves resistance to the drug schemes developed against it. For this reason, it remains urgent to find innovative therapeutic strategies offering sufficient specificity against the parasite to minimize resistance evolution and drug side effects. In this context, nanotechnology-based approaches are now being explored for their use as antimalarial drug delivery platforms due to the wide range of advantages and tuneable properties that they offer. However, major challenges remain to be addressed to provide a cost-efficient and targeted therapeutic strategy contributing to malaria eradication. The present work contains a systematic review of nanotechnology-based antimalarial drug delivery systems generated during the last 10 years. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease

JTD Keywords: Adjuvant system, Antimalarial activities, Antimalarial agent, Antimalarial drug, Antimalarial drugs, Antimalarials, Artemisinin resistance, Causes of death, Child, Controlled drug delivery, Diseases, Drug delivery system, Drug delivery systems, Drug interactions, Drug side-effects, Drug-delivery, Experimental modelling, Heparan-sulfate, Human, Humans, In-vitro, Malaria, Malaria vaccine, Mannosylated liposomes, Medical nanotechnology, Models, theoretical, Nanocarriers, Nanomedicine, Nanotechnology, Parasite-, Parasitics, Plasmodium, Plasmodium-falciparum malaria, Red-blood-cells, Targeted delivery, Targeted drug delivery, Theoretical model, Therapeutic strategy

From complex -mixture analysis to in vivo molecular imaging, applications of liquid -state nuclear spin hyperpolarization have expanded widely over recent years. In most cases, hyperpolarized solutions are generated and transported from the polarization instrument to the measurement device. The sample hyperpolarization usually survives this transport, since the changes in magnetic fields that are external to the sample are typically adiabatic (slow) with respect to the internal nuclear spin dynamics. The passage of polarized samples through weakly magnetic components such as stainless steel syringe needles and ferrules is not always adiabatic, can lead to near -complete destruction of the magnetization. To avoid this effect becoming "folklore"in field of hyperpolarized NMR, we present a systematic investigation to highlight the problem and investigate possible solutions. Experiments were carried out on: (i) dissolution-DNP-polarized [1-13C]pyruvate with detection at 1.4 T, and (ii) 1.5 -T -polarized H2O with NMR detection at 2.5 mu T. We show that the degree adiabaticity of solutions passing through metal parts is intrinsically unpredictable, likely depending on factors such as solution flow rate, degree of remanent ferromagnetism in the metal, and nuclear spin However, the magnetization destruction effects can be suppressed by application of an external field order of 0.1-10 mT.

JTD Keywords: Benchtop nmr, Hyperpolarization, Low-field mri, Non-adiabatic, Para-hydrogen, Spin relaxation

Human mesenchymal stromal cells (hMSCs) seeded on calcium phosphate (CaP) bioceramics are extensively explored in bone tissue engineering and have recently shown effective clinical outcomes. In previous pre-clinical studies, hMSCs-CaP-mediated bone formation was preceded by osteoclastogenesis at the implantation site. The current study evaluates to what extent phase composition of CaPs affects the osteoclast response and ultimately influence bone formation. To this end, four different CaP bioceramics were used, hydroxyapatite (HA), beta-tricalcium phosphate (beta-TCP) and two biphasic composites of HA/beta- TCP ratios of 60/40 and 20/80 respectively, for in vitro osteoclast differentiation and correlation with in vivo osteoclastogenesis and bone formation. All ceramics allowed osteoclast formation in vitro from mouse and human precursors, except for pure HA, which significantly impaired their maturation. Ectopic implantation alongside hMSCs in subcutis sites of nude mice revealed new bone formation at 8 weeks in all conditions with relative amounts for beta-TCP > biphasic CaPs > HA. Surprisingly, while hMSCs were essential for osteoinduction, their survival did not correlate with bone formation. By contrast, the degree of early osteoclastogenesis (2 weeks) seemed to define the extent of subsequent bone formation. Together, our findings suggest that the osteoclastic response could be used as a predictive marker in hMSC-CaPbased bone regeneration and strengthens the need to understand the underlying mechanisms for future biomaterial development. Statement of significance The combination of mesenchymal stromal cells (MSCs) and calcium phosphate (CaP) materials has demonstrated its safety and efficacy for bone regeneration in clinical trials, despite our insufficient understanding of the underlying biological mechanisms. Osteoclasts were previously suggested as key mediators between the early inflammatory phase following biomaterial implantation and the subsequent bone formation. Here we compared the affinity of osteoclasts for various CaP materials with different ratios of hydroxyapatite to beta-tricalcium phosphate. We found that osteoclast formation, both in vitro and at early stages in vivo, correlates with bone formation when the materials were implanted alongside MSCs in mice. Surprisingly, MSC survival did not correlate with bone formation, suggesting that the number or phenotype of osteoclasts formed was more important. (c) 2024 The Author(s). Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

JTD Keywords: Acid phosphatase tartrate resistant isoenzyme, Animal, Animal cell, Animal experiment, Animal tissue, Animals, Article, Beta-tricalcium phosphate, Bioceramics, Biocompatible materials, Biomaterial, Bone, Bone development, Bone formation, Bone regeneration, Calcium phosphate, Calcium phosphate materials, Calcium phosphates, Cd14 antigen, Cell differentiation, Cell engineering, Cell maturation, Cell survival, Ceramics, Chemical composition, Controlled study, Correlation analysis, Correlation coefficient, Data correlation, Durapatite, Engraftment, Flowcharting, Human, Human cell, Human mesenchymal stromal cell, Human mesenchymal stromal cells, Humans, Hydroxyapatite, Hydroxyapatites, In vitro study, In vivo study, In-vitro, In-vivo, Mammals, Marrow stromal cells, Material composition, Material compositions, Mesenchymal stroma cell, Mesenchymal stromal cells, Mice, Mice, nude, Monocyte, Mouse, Nonhuman, Nude mouse, Ossification, Osteoclast, Osteoclastogenesis, Osteoclasts, Osteogenesis, Osteoinduction, Phase composition, Regeneration strategies, Resorption, Scaffolds, Stem-cells, Subcutaneous tissue, Tissue engineering, Transmission control protocol, Tri-calcium phosphates, Vimentin

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

Polypropylene (PP), thermoplastic polyurethane (TPU), polyethylene terephthalate glycol (PETG) and polylactic acid (PLA) 3D printed specimens, which are intrinsically non-electroresponsive materials, have been converted into electroresponsive electrodes applying a low-pressure oxygen plasma treatment. After complete chemical, morphological and electrochemical characterization, plasma treated samples have been applied as integrated electrochemical sensors for detecting dopamine and serotonin by cyclic voltammetry and chronoamperometry. Results show differences in the sensing behavior, which have been explained on the basis of the chemical structure of the pristine materials. While plasma treated PLA exhibits the highest performance as electrochemical sensor in terms of sensitivity (lowest limits of detection and quantification) and selectivity (against uric acid and ascorbic acid as interfering substances), plasma treated PP displays the poorest behavior due to its low polarity compared to PLA 3D-printed electrodes. Instead, plasma treated TPU and PETG shows a very good response, much closer to PLA, as sensitive electrodes towards neurotransmitter molecules (dopamine and serotonin). Overall, results open a new door for the fabrication of electrochemical conductive sensors using intrinsically insulating materials, without the need of chemical functionalization processes.

JTD Keywords: 3d printing, Amines, Ascorbic acid, Chemical characterization, Cyclic voltammetry, Dopamine, Electrochemical characterizations, Electrochemical sensor s, Electrochemical sensors, Electrode materials, Electroresponsive materials, Low-pressure oxygen-plasma treatments, Morphological characterization, Multiwalled carbon nanotubes (mwcn), Neurophysiology, Oxygen, Oxygen plasmas, Plastic bottles, Polyethylene terephthalate glycol, Polyethylene terephthalate glycols, Polyethylene terephthalates, Polylact i c acid, Polylactic acid, Polylactic acid pla, Polyols, Polypropylene, Polypropylene oxides, Polypropylenes, Polyurethanes, Reinforced plastics, Supercapacitors, Thermoplast i c polyurethane, Thermoplastic polyurethane, Thermoplastic polyurethanes

Microbial biofilms are complex three-dimensional structures where sessile microbes are embedded in a polymeric extracellular matrix. Their resistance toward the host immune system as well as to a diverse range of antimicrobial treatments poses a serious health and development threat, being in the top 10 global public health threats declared by the World Health Organization. In an effort to combat biofilm-related microbial infections, several strategies have been developed to independently eliminate biofilms or to complement conventional antibiotic therapies. However, their limitations leave room for other treatment alternatives, where the application of nanotechnology to biofilm eradication has gained significant relevance in recent years. Their small size, penetration efficiency, and the design flexibility that they present makes them a promising alternative for biofilm infection treatment, although they also present set-backs. This review aims to describe the main possibilities and limitations of nanomedicine against biofilms, while covering the main aspects of biofilm formation and study, and the current therapies for biofilm treatment. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine.

JTD Keywords: Anti-bacterial agents, Anti-infective agents, Antiinfective agent, Antimicrobial, Antimicrobials, Antimicrobials,bacteria,biofilm,infectious diseases,microorganism, Bacteria, Biofilm, Biofilm infections, Biofilms, Complex three dimensional structures, Diseases, Diverse range, Drug-delivery systems,in-vitro,cellular toxicity,nanoparticles,penetration,model,biocompatibility,perspectives,hyperthermia,diagnosi, Extracellular matrices, Global public health, Health risks, Infectious disease, Infectious diseases, Medical nanotechnology, Microbial biofilm, Microorganisms, Nanomedicine, Polymer, Polymers, Regulatory issues, Roadmap

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

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

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

Factor XII (FXII) is a zymogen present in blood that tends to adsorb onto the surfaces of blood-contacting medical devices. Once adsorbed, it becomes activated, initiating a cascade of enzymatic reactions that lead to surface-induced coagulation. This process is characterized by multiple redundancies, making it extremely challenging to prevent clot formation and preserve the properties of the surface. In this study, a novel modulatory coating system based on C1-esterase inhibitor (C1INH) functionalized polymer brushes, which effectively regulates the activation of FXII is proposed. Using surface plasmon resonance it is demonstrated that this coating system effectively repels blood plasma proteins, including FXII, while exhibiting high activity against activated FXII and plasma kallikrein under physiological conditions. This unique property enables the modulation of FXII activation without interfering with the overall hemostasis process. Furthermore, through dynamic Chandler loop studies, it is shown that this coating significantly improves the hemocompatibility of polymeric surfaces commonly used in medical devices. By addressing the root cause of contact activation, the synergistic interplay between the antifouling polymer brushes and the modulatory C1INH is expected to lay the foundation to enhance the hemocompatibility of medical device surfaces.© 2023 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.

JTD Keywords: adsorption, binding, c1-esterase-inhibitor, coatings, contact activation, factor-xii, fxii activation, hemocompatibility, hemocompatible surface modification, heparin, polymer brushes, system, thrombosis, Adsorption, Anticoagulation, Antifouling agent, Article, Beta-fxiia, Biocompatibility, Blood, Blood clotting, Blood clotting factor 12, Blood clotting factor 12a, Blood clotting factor 12a inhibitor, Blood coagulation, C1-esterase-inhibitor, Cell activation, Chemical activation, Coagulation, Coating (procedure), Complement component c1s inhibitor, Complement system, Controlled study, Dendrimers, Enzyme immobilization, Enzymes, Erythrocyte, Esters, Factor xii, Factor xii activation, Factor xiia, Fibrin deposition, Functional polymers, Fxii activation, Haemocompatibility, Hemocompatibility, Hemocompatible surface modification, Hemostasis, Heparin, Human, Hydrogel, Medical devices, Metabolism, Plasma kallikrein, Plasma protein, Plastic coatings, Platelet count, Polymer, Polymer brushes, Polymerization, Polymers, Property, Root cause, Surface plasmon resonance, Surface property, Surface reactions, Surface-modification, Thrombocyte adhesion, Β-fxiia

Neuroblastoma (NB) is a highly vascularized pediatric tumor arising from undifferentiated neural crest cells early in life, exhibiting both traditional endothelial-cell-driven vasculature and an intriguing alternative vasculature. The alternative vasculature can arise from cancer cells undergoing transdifferentiation into tumor-derived endothelial cells (TEC), a trait associated with drug resistance and tumor relapse. The lack of effective treatments targeting NB vasculature primarily arises from the challenge of establishing predictive in vitro models that faithfully replicate the alternative vasculature phenomenon. In this study, we aim to recreate the intricate vascular system of NB in an in vitro context, encompassing both types of vascularization, by developing a novel neuroblastoma-on-a-chip model. We designed a collagen I/fibrin-based hydrogel closely mirroring NB's physiological composition and tumor stiffness. This biomaterial created a supportive environment for the viability of NB and endothelial cells. Implementing a physiological shear stress value, aligned with the observed range in arteries and capillaries, within the microfluidic chip facilitated the successful development of vessel-like structures and triggered transdifferentiation of NB cells into TECs. The vascularized neuroblastoma-on-a-chip model introduced here presents a promising and complementary strategy to animal-based research with a significant capacity for delving into NB tumor biology and vascular targeting therapy.

JTD Keywords: 3d tumor model, Angiogenesis, Endothelial-cells, Microfluidic device, Neuroblastoma, Origi, Transdifferentiation, Tumor, Tumor-derived endothelial cells, Tumor-on-a-chip, Vasculature

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

The accurate spatial segregation into distinct phases within cell membranes coordinates vital biochemical processes and functionalities in living organisms. One of nature's strategies to localize reactivity is the formation of dynamic raft domains. Most raft models rely on liquid-ordered L-0 phases in a liquid-disordered L-d phase lacking correlation and remaining static, often necessitating external agents for phase separation. Here, we introduce a synthetic system of bicomponent glycodendrimersomes coassembled from Janus dendrimers and Janus glycodendrimers (JGDs), where lactose-lactose interactions exclusively drive lateral organization. This mechanism results in modulated phases across two length scales, yielding raft-like microdomains featuring nanoarrays at the nanoscale. By varying the density of lactose and molecular architecture of JGDs, the nanoarray type and size, shape, and spacing of the domains were controlled. Our findings offer insight into the potential primordial origins of rudimentary raft domains and highlight the crucial role of glycans within the glycocalyx.

JTD Keywords: Article, Artificial cells, Atomic force microscopy, Bicomponents, Bilayer, Bilayer membrane, Biochemical functionality, Biochemical process, Biological-membranes, Cell component, Cell membrane, Cellular parameters, Chemical interaction, Chemical structure, Chemistry, Cytology, Defined janus glycodendrimers, Dehydration, Dendrimer, Dendrimers, Dilution, Dimer, External agents, Fourier transform, Giant vesicles, Glycan, Glycans, Glycocalyx, Glycodendrimers, Janus dendrimer, Janus glycodendrimer, Lactose, Lateral organization, Lectin, Lipid rafts, Living organisms, Membrane damage, Membrane microdomain, Membrane microdomains, Membrane structure, Metabolism, Modulated phases, Molecule, Monomer, Nanoarrays, Oligosaccharide, Organization, Periodicity, Phase separation, Phase-separation, Phospholipids, Polysaccharide, Polysaccharides, Raft like domain, Relative humidity, Spatial segregation, Structure analysis, Sugars, Synthetic systems, Tetramer, Unclassified drug, Unilamellar vesicles, Water

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

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

Introduction: Candida parapsilosis, a pathogenic yeast associated with systemic infections, exhibits metabolic adaptability in response to nutrient availability.Methods: We investigated the impact of RPMI glucose supplemented (RPMId), TSB, BHI and YPD media on C. parapsilosis growth, morphology, susceptibility (caspofungin and amphotericin B), and in vivo virulence (Galleria mellonella) in planktonic and biofilm states.Results: High-glucose media favors growth but hinders metabolic activity and filamentation. Media promoting carbohydrate production reduces biofilm susceptibility. Virulence differences between planktonic cells and biofilm suspensions from the same media shows that biofilm-related factors influence infection outcome depending on nutrient availability. Pseudohyphal growth occurred in biofilms under low oxygen and shear stress, but its presence is not exclusively correlated with virulence.Discussion: This study provides valuable insights into the intricate interplay between nutrient availability and C. parapsilosis pathogenicity. It emphasizes the importance of considering pathogen behavior in diverse conditions when designing research protocols and therapeutic strategies.

JTD Keywords: Amphotericin b, Antifungal, Biofilm, Candida, Caspofungin, Galleria mellonella, Pathogenicity, Pseudohyphal growth

Current strategies to identify ligands for brain delivery select candidates based on preferential binding to cell-membrane components (CMC) on brain endothelial cells (EC). However, such strategies generate ligands with inherent brain specificity limitations, as the CMC (e.g., the transferrin receptor TfR1) are also significantly expressed on peripheral EC. Therefore, novel strategies are required to identify molecules allowing increased specificity of therapy brain delivery. Here, we demonstrate that, while individual CMC are shared between brain EC and peripheral EC, their endocytic internalization rate is markedly different. Such differential endocytic rate may be harnessed to identify molecular tags for brain targeting based on their selective retention on the surface of brain EC, thereby generating 'artificial' targets specifically on the brain vasculature. By quantifying the retention of labelled proteins on the cell membrane, we measured the general endocytic rate of primary brain EC to be less than half that of primary peripheral (liver and lung) EC. In addition, through bio-panning of phage-displayed peptide libraries, we unbiasedly probed the endocytic rate of individual CMC of liver, lung and brain endothelial cells. We identified phage-displayed peptides which bind to CMC common to all three endothelia phenotypes, but which are preferentially endocytosed into peripheral EC, resulting in selective retention on the surface of brain EC. Furthermore, we demonstrate that the synthesized free-form peptides are capable of generating artificial cell-surface targets for the intracellular delivery of model proteins into brain EC with increasing specificity over time. The developed identification paradigm, therefore, demonstrates that the lower endocytic rate of individual CMC on brain EC can be harnessed to identify peptides capable of generating 'artificial' targets for the selective delivery of proteins into the brain vasculature. In addition, our approach identifies brain-targeting peptides which would have been overlooked by conventional identification strategies, thereby increasing the repertoire of candidates to achieve specific therapy brain delivery.© 2023. The Author(s).

JTD Keywords: brain endothelium, endocytic rates, ligand identification, nanoparticles, phage-display, Barrier, Brain, Brain endothelium, Brain targeting, Endocytic rates, Endothelial cells, Endothelium, Ligand identification, Peptides, Phage-display

We demonstrate that enzyme-catalyzed reactions can be observed in zero- and low-field NMR experiments by combining recent advances in parahydrogen-based hyperpolarization methods with state-of-the-art magnetometry. Specifically, we investigated two model biological processes: the conversion of fumarate into malate, which is used in vivo as a marker of cell necrosis, and the conversion of pyruvate into lactate, which is the most widely studied metabolic process in hyperpolarization-enhanced imaging. In addition to this, we constructed a microfluidic zero-field NMR setup to perform experiments on microliter-scale samples of [1-C-13]-fumarate in a lab-on-a-chip device. Zero- to ultralow-field (ZULF) NMR has two key advantages over high-field NMR: the signals can pass through conductive materials (e.g., metals), and line broadening from sample heterogeneity is negligible. To date, the use of ZULF NMR for process monitoring has been limited to studying hydrogenation reactions. In this work, we demonstrate this emerging analytical technique for more general reaction monitoring and compare zero- vs low-field detection.

JTD Keywords: Fumarates, Hydrogenation, Magnetic resonance imaging, Magnetic resonance spectroscopy, Nmr j-spectroscopy, Pyruvic acid

The cell nucleus plays a key role in cellular mechanoresponses. 3D genome organisation, gene expression, and cell behaviour, in general, are affected by mechanical force application to the nucleus, which is transmitted from the cellular environment via a network of interconnected cytoskeletal components. To effectively regulate cell responses, these cytoskeletal components must not only exert forces but also withstand external forces when necessary. This review delves into the latest research concerning how the cytoskeleton safeguards the nucleus from mechanical perturbations. Spe-cifically, we focus on the three primary cytoskeletal polymers: actin, intermediate filaments, and microtubules, as well as their interactions with the cell nucleus. We discuss how the cyto-skeleton acts as a protective shield for the nucleus, ensuring structural integrity and conveying context-specific mechanoresponses.

JTD Keywords: Actin, Architecture, Cytoskeleton, Envelope, F-actin, Filaments, Force, Genome, Intermediate filaments, Lamin, Mechanotransduction, Membrane protein, Microtubules, Nesprin-1, Nucleus

ASM deficiency in Niemann-Pick disease type A results in aberrant cellular accumulation of sphingomyelin, neuroinflammation, neurodegeneration, and early death. There is no available treatment because enzyme replacement therapy cannot surmount the blood-brain barrier (BBB). Nanocarriers (NCs) targeted across the BBB via transcytosis might help; yet, whether ASM deficiency alters transcytosis remains poorly characterized. We investigated this using model NCs targeted to intracellular adhesion molecule-1 (ICAM-1), transferrin receptor (TfR), or plasmalemma vesicle-associated protein-1 (PV1) in ASM-normal vs. ASM-deficient BBB models. Disease differentially changed the expression of all three targets, with ICAM-1 becoming the highest. Apical binding and uptake of anti-TfR NCs and anti-PV1 NCs were unaffected by disease, while anti-ICAM-1 NCs had increased apical binding and decreased uptake rate, resulting in unchanged intracellular NCs. Additionally, anti-ICAM-1 NCs underwent basolateral reuptake after transcytosis, whose rate was decreased by disease, as for apical uptake. Consequently, disease increased the effective transcytosis rate for anti-ICAM-1 NCs. Increased transcytosis was also observed for anti-PV1 NCs, while anti-TfR NCs remained unaffected. A fraction of each formulation trafficked to endothelial lysosomes. This was decreased in disease for anti-ICAM-1 NCs and anti-PV1 NCs, agreeing with opposite transcytosis changes, while it increased for anti-TfR NCs. Overall, these variations in receptor expression and NC transport resulted in anti-ICAM-1 NCs displaying the highest absolute transcytosis in the disease condition. Furthermore, these results revealed that ASM deficiency can differently alter these processes depending on the particular target, for which this type of study is key to guide the design of therapeutic NCs.© 2023. Controlled Release Society.

JTD Keywords: asm deficiency, blood-brain barrier, delivery, determines, drug, endocytosis, enzymes, icam-1, lysosomal storage disease, mechanisms, nanoparticles, natural-history, niemann-pick disease type a, pv-1, receptor-mediated transcytosis, trafficking, transferrin receptor, Asm deficiency, Blood-brain barrier, Blood–brain barrier, Drug carriers, Drug nanocarriers, Humans, Icam-1, Icam-1-targeted nanocarriers, Intercellular adhesion molecule-1, Lysosomal storage disease, Niemann-pick disease type a, Niemann-pick disease, type a, Niemann-pick diseases, Pv-1, Receptor-mediated transcytosis, Transferrin receptor

The combination of a powerful and broadly applicable nuclear hyperpolarization technique with emerging (near-)zero-field modalities offers novel opportunities in a broad range of nuclear magnetic resonance spectroscopy and imaging applications, including biomedical diagnostics, monitoring catalytic reactions within metal reactors and many others. These are discussed along with a roadmap for future developments.

JTD Keywords: Couplings, Hyperpolarization, Nmr, Parahydrogen, Phase, Radicals, Time

Recently, organoids have emerged as revolutionizing tools with the unprecedented potential to recreate organ-specific microanatomy in vitro. Upon their derivation from human pluripotent stem cells (hPSCs), organoids reveal the blueprints of human organogenesis, further allowing the faithful recapitulation of their physiology. Nevertheless, along with the evolution of this field, advanced research exposed the organoids' shortcomings, particularly regarding poor reproducibility rates and overall immatureness. To resolve these challenges, many studies have started to underscore the relevance of mechanical cues as a relevant source to induce and externally control hPSCs differentiation. Indeed, established organoid generation protocols from hPSCs have mainly relyed on the biochemical induction of fundamental signalling pathways present during kidney formation in mammals, whereas mechanical cues have largely been unexplored. This review aims to discuss the pertinence of (bio) physical cues within hPSCs-derived organoid cultures, while deciphering their effect on morphogenesis. Moreover, we will explore state-of-the-art mechanobiology techniques as revolutionizing means for understanding the underlying role of mechanical forces in biological processes in organoid model systems.

JTD Keywords: development, hpscs, mechanobiology, nephrogenesis, Activated ion-channel, Development, Extracellular-matrix viscoelasticity, Forces, Hpscs, Ips cells, Mechanical regulation, Mechanobiology, Nephrogenesis, Nephron progenitors, Organoids, Pluripotent stem-cells, Self-renewal, Substrate mechanics, Tissue

Many neurodegenerative diseases are identified but their causes and cure are far from being well-known. The problem resides in the complexity of the neural tissue and its location which hinders its easy evaluation. Although necessary in the drug discovery process, in vivo animal models need to be reduced and show relevant differences with the human tissues that guide scientists to inquire about other possible options which lead to in vitro models being explored. From organoids to organ-on-a-chips, 3D models are considered the cutting-edge technology in cell culture. Cell choice is a big parameter to take into consideration when planning an in vitro model and cells capable of mimicking both healthy and diseased tissue, such as induced pluripotent stem cells (iPSC), are recognized as good candidates. Hence, we present a critical review of the latest models used to study neurodegenerative disease, how these models have evolved introducing microfluidics platforms, 3D cell cultures, and the use of induced pluripotent cells to better mimic the neural tissue environment in pathological conditions.

JTD Keywords: 3d in vitro models, bioprinting, ipsc cell culture, microfluidic device, 3d in vitro models, Bioprinting, Blood-brain-barrier, Cerebral organoids, Culture model, Endothelial-cells, Expression profile, Extracellular-matrix, Ipsc cell culture, Microfluidic device, Neurodegenerative diseases, On-a-chip, Pluripotent stem-cells, Shear-stress, Substrate stiffness

The Boston keratoprosthesis (BKPro) is a medical device used to restore vision in complicated cases of corneal blindness. This device is composed by a front plate of polymethylmethacrylate (PMMA) and a backplate usually made of titanium (Ti). Ti is an excellent biomaterial with numerous applications, although there are not many studies that address its interaction with ocular cells. In this regard, despite the good retention rates of the BKPro, two main complications compromise patients' vision and the viability of the prosthesis: imperfect adhesion of the corneal tissue to the upside of the backplate and infections. Thus, in this work, two topographies (smooth and rough) were generated on Ti samples and tested with or without functionalization with a dual peptide platform. This molecule consists of a branched structure that links two peptide moieties to address the main complications associated with BKPro: the well-known RGD peptide in its cyclic version (cRGD) as cell pro-adherent motif and the first 11 residues of lactoferrin (LF1-11) as antibacterial motif. Samples were physicochemically characterized, and their biological response was evaluated in vitro with human corneal keratocytes (HCKs) and against the gram-negative bacterial strain Pseudomonas aeruginosa. The physicochemical characterization allowed to verify the functionalization in a qualitative and quantitative manner. A higher amount of peptide was anchored to the rough surfaces. The studies performed using HCKs showed increased long-term proliferation on the functionalized samples. Gene expression was affected by topography and peptide functionalization. Roughness promoted α-smooth muscle actin (α-SMA) overexpression, and the coating notably increased the expression of extracellular matrix components (ECM). Such changes may favour the development of unwanted fibrosis, and thus, corneal haze. In contrast, the combination of the coating with a rough topography decreased the expression of α-SMA and ECM components, which would be desirable for the long-term success of the prosthesis. Regarding the antibacterial activity, the functionalized smooth and rough surfaces promoted the death of bacteria, as well as a perturbation in their wall definition and cellular morphology. Bacterial killing values were 58 % for smooth functionalised and 68 % for rough functionalised samples. In summary, this study suggests that the use of the dual peptide platform with cRGD and LF1-11 could be a good strategy to improve the in vitro and in vivo performance of the rough topography used in the commercial BKPro.Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.

JTD Keywords: binding, corneal blindness, differentiation, dual coating, iii collagen, in-vitro, infectious endophthalmitis, keratocyte, myofibroblast, peptide platform, proliferation, surface-roughness, titanium implant, Boston keratoprostheses, Corneal blindness, Dual coating, Gram-negative bacteria, Peptide platform, Titanium implant

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

Fluorescent proteins, such as green fluorescent proteins, are invaluable tools for detecting and quantifying gene expression in high-throughput reporter gene assays. However, they introduce significant inaccuracies in studies involving microaerobiosis or anaerobiosis, as oxygen is required for the maturation of these proteins' chromophores. In this study, the authors highlight the errors incurred by using fluorescent proteins under limited oxygenation by comparing standard fluorescence-based reporter gene assays to quantitative real-time PCR data in the study of a complex oxygen-regulated gene network. Furthermore, a solution to perform quantification of anaerobic and microaerobic gene expression with fluorescent reporter proteins using a microplate reader with an oxygen control system and applying pulses of full oxygenation before fluorescence measurements is provided.

JTD Keywords: fluorescent proteins, gene expression, gfp, microaerobiosis, promoters, reporter gene assay, transcriptional fusion, Anaerobiosis, Fluorescent proteins, Gene expression, Gfp, Microaerobiosis, Pseudomonas-aeruginosa, Reporter gene assay, Transcriptional fusion

Decellularized extracellular matrix (dECM) hydrogels have emerged as promising materials in tissue engineering. The steps to produce dECM hydrogels containing the bioactive epitopes found in the native matrix are often laborious, including the initial harvesting and decellularization of the animal organ. Furthermore, resulting hydrogels often exhibit weak mechanical properties that require the use of additional crosslinkers such as genipin to truly simulate the mechanical properties of the desired study tissue. In this work, we have developed a protocol to readily obtain tens of thin dECM hydrogel cryosections attached to a glass slide as support, to serve as scaffolds for two-dimensional (2D) or three-dimensional (3D) cell culture. Following extensive atomic force microscopy (AFM)-based mechanical characterization of dECM hydrogels crosslinked with increasing genipin concentrations (5 mM, 10 mM, and 20 mM), we provide detailed protocol recommendations for achieving dECM hydrogels of any biologically relevant stiffness. Given that our protocol requires hydrogel freezing, we also confirm that the approach taken can be further used to increase the mechanical properties of the scaffold in a controlled manner exhibiting twice the stiffness in highly crosslinked arrays. Finally, we explored the effect of ethanol-based short- and long-term sterilization on dECM hydrogels, showing that in some situations it may give rise to significant changes in hydrogel mechanical properties that need to be taken into account in experimental design. The hydrogel cryosections produced were shown to be biocompatible and support cell attachment and spreading for at least 72 h in culture. In brief, our proposed method may provide several advantages for tissue engineering: (1) easy availability and reduction in preparation time, (2) increase in the total hydrogel volume eventually used for experiments being able to obtain 15-22 slides from a 250 µL hydrogel) with a (3) reduction in scaffold variability (only a 17.5 ± 9.5% intraslide variability provided by the method), and (4) compatibility with live-cell imaging techniques or further cell characterization of cells.

JTD Keywords: atomic force microscopy, cryogel, cryosectioning, decellularization, extracellular matrix, genipin, sterilization, stiffness, young's modulus, Atomic force microscopy, Cryogel, Cryosectioning, Decellularization, Extracellular matrix, Genipin, Hydrogel, Sterilization, Stiffness, Young’s modulus

A novel family of 4-aminoacridine derivatives was obtained by linking this heteroaromatic core to different trans-cinnamic acids. The 4-(N-cinnamoylbutyl)aminoacridines obtained exhibited in vitro activity in the low- or sub-micromolar range against (i) hepatic stages of Plasmodium berghei, (ii) erythrocytic forms of Plasmodium falciparum, and (iii) early and mature gametocytes of Plasmodium falciparum. The most active compound, having a meta-fluorocinnamoyl group linked to the acridine core, was 20- and 120-fold more potent, respectively, against the hepatic and gametocyte stages of Plasmodium infection than the reference drug, primaquine. Moreover, no cytotoxicity towards mammalian and red blood cells at the concentrations tested was observed for any of the compounds under investigation. These novel conjugates represent promising leads for the development of new multi-target antiplasmodials.Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

JTD Keywords: agents, analogs, antimalarial, artemisinin, blood-stage, cinnamic acid, gametocyte, hybrid, liver-stage, malaria, multi-target, plasmodium-falciparum, primaquine, quinacrine, resistance, Acridine, Antimalarial, Blood-stage, Cinnamic acid, Cinnamic acid-derivatives, Gametocyte, Hybrid, Liver-stage, Multi-target

Neurotrophic factors are essential not only for guiding the organization of the developing nervous system but also for supporting the survival and growth of neurons after traumatic injury. In the central nervous system (CNS), inhibitory factors and the formation of a glial scar after injury hinder the functional recovery of neurons, requiring exogenous therapies to promote regeneration. Netrin-1, a neurotrophic factor, can initiate axon guidance, outgrowth, and branching, as well as synaptogenesis, through activation of deleted in colorectal cancer (DCC) receptors. We report here the development of a nanofiber-shaped supramolecular mimetic of netrin-1 with monomers that incorporate a cyclic peptide sequence as the bioactive component. The mimetic structure was found to activate the DCC receptor in primary cortical neurons using low molar ratios of the bioactive comonomer. The supramolecular nanofibers enhanced neurite outgrowth and upregulated maturation as well as pre- and postsynaptic markers over time, resulting in differences in electrical activity similar to neurons treated with the recombinant netrin-1 protein. The results suggest the possibility of using the supramolecular structure as a therapeutic to promote regenerative bioactivity in CNS injuries.

JTD Keywords: axon growth, axon guidance, cell-migration, colorectal-cancer, dcc, dopaminergic-neurons, force-field, functional recovery, netrin-1, neurite outgrowth, neuronal maturation, neurotrophic factor, neurotrophicfactor mimetic, synapsis, Axon growth, Axons, Cells, cultured, Central nervous system, Coarse-grained model, Nanofibers, Netrin-1, Neurogenesis, Neuronal maturation, Neurons, Neurotrophic factor mimetic, Peptide amphiphile, Synapsis

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

Anisotropy is an important cue for neural organization during morphogenesis and healing, contributing to the mechanical and functional properties of neural tissues. The ability to replicate such anisotropy in vitro holds great promise for the development of effective regeneration strategies. In this work, interfacial polyelectrolyte complexation (IPC) is applied to fabricate microfibers from charged ECM components without any chemical modification. Using flow-focusing microfluidics, collagen (Col) and glycosaminoglycans (GAGs), such as chondroitin sulfate (CS) or heparin (Hep), form Col/CS and Col/Hep interfacial complexes that coalesce as IPC microfibers. These fibers are flexible and absorb large amounts of water but remain stable under physiological conditions. At these conditions, the tensile strength of the assembled Col/GAG microfibers is similar to the strength of the neural tissue. The fibers are biocompatible and biofunctional; PC12 neural cells adhere and orient longitudinally to the fibers. Moreover, Col/CS microfibers promote the formation of neural processes. The results demonstrate that the microfluidic-assisted IPC complexation enables the assembly of ECM mimics by synergetic integration of anisotropic, chemical, and mechanical cues that boost the development of neural cells.

JTD Keywords: Cells, Chondroitin sulfate, Collagen, Fibers, Glycosaminoglycans, Heparin, Microfibers

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

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

Duchenne muscular dystrophy (DMD) is the most prevalent neuromuscular disease diagnosed in childhood. It is a progressive and wasting disease, characterized by a degeneration of skeletal and cardiac muscles caused by the lack of dystrophin protein. The absence of this crucial structural protein leads to sarcolemmal fragility, resulting in muscle fiber damage during contraction. Despite ongoing efforts, there is no cure available for DMD patients. One of the primary challenges is the limited efficacy of current preclinical tools, which fail in modeling the biological complexity of the disease. Human-based three-dimensional (3D) cell culture methods appear as a novel approach to accelerate preclinical research by enhancing the reproduction of pathophysiological processes in skeletal muscle. In this work, we developed a patient-derived functional 3D skeletal muscle model of DMD that reproduces the sarcolemmal damage found in the native DMD muscle. These bioengineered skeletal muscle tissues exhibit contractile functionality, as they responded to electrical pulse stimulation. Sustained contractile regimes induced the loss of myotube integrity, mirroring the pathological myotube breakdown inherent in DMD due to sarcolemmal instability. Moreover, damaged DMD tissues showed disease functional phenotypes, such as tetanic fatigue. We also evaluated the therapeutic effect of utrophin upregulator drug candidates on the functionality of the skeletal muscle tissues, thus providing deeper insight into the real impact of these treatments. Overall, our findings underscore the potential of bioengineered 3D skeletal muscle technology to advance DMD research and facilitate the development of novel therapies for DMD and related neuromuscular disorders.

JTD Keywords: 3d cell culture, disease modeling, drug testing, duchenne muscular dystrophy, sarcolemmal damage, skeletal muscle, 3d cell culture, Animal-models, Disease modeling, Dmso, Drug testing, Duchenne muscular dystrophy, Gene, Humans, Image, Mechanisms, Muscle fibers, skeletal, Muscle, skeletal, Muscular dystrophy, duchenne, Myocardium, Sarcolemmal damage, Skeletal muscle, Tissue engineering, Utrophin

ReViTA (Reverse in VitroTranscription Assay) is a novel in vitro transcription-based method to study gene expression under the regulation of specific transcription factors. The ReViTA system uses a plasmid with a control sequence, the promoter region of the studied gene, the transcription factor of interest, and an RNA polymerase saturated with σ70. The main objective of this study was to evaluate the method; thus, as a proof of concept, two different transcription factors were used, a transcriptional inducer, AlgR, and a repressor, LexA, from Pseudomonas aeruginosa. After the promoters were incubated with the transcription factors, the plasmid was transcribed into RNA and reverse transcribed to cDNA. Gene expression was measured using qRTPCR. Using the ReViTA plasmid, transcription induction of 55% was observed when AlgR protein was added and a 27% transcription reduction with the repressor LexA, compared with the samples without transcription factors. The results demonstrated the correct functioning of ReViTA as a novel method to study transcription factors and gene expression. Thus, ReViTA could be a rapid and accessible in vitro method to evaluate genes and regulators of various species.Crown Copyright © 2023. Published by Elsevier B.V. All rights reserved.

JTD Keywords: binding, dna-polymerase-iv, gene expression, in vitro transcription, lexa, rpos, transcription factor, transcriptional regulation, Gene expression, Response sigma-factor, Transcriptional regulation

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer, with survival rates exceeding 85%. However, 15% of patients will relapse; consequently, their survival rates decrease to below 50%. Therefore, several research and innovation studies are focusing on pediatric relapsed or refractory ALL (R/R ALL). Driven by this context and following the European strategic plan to implement precision medicine equitably, the Relapsed ALL Network (ReALLNet) was launched under the umbrella of SEHOP in 2021, aiming to connect bedside patient care with expert groups in R/R ALL in an interdisciplinary and multicentric network. To achieve this objective, a board consisting of experts in diagnosis, management, preclinical research, and clinical trials has been established. The requirements of treatment centers have been evaluated, and the available oncogenomic and functional study resources have been assessed and organized. A shipping platform has been developed to process samples requiring study derivation, and an integrated diagnostic committee has been established to report results. These biological data, as well as patient outcomes, are collected in a national registry. Additionally, samples from all patients are stored in a biobank. This comprehensive repository of data and samples is expected to foster an environment where preclinical researchers and data scientists can seek to meet the complex needs of this challenging population. This proof of concept aims to demonstrate that a network-based organization, such as that embodied by ReALLNet, provides the ideal niche for the equitable and efficient implementation of "what's next" in the management of children with R/R ALL.© 2023 Velasco, Bautista, Rubio, Aguilar, Rives, Dapena, Pérez, Ramirez, Saiz-Ladera, Izquierdo, Escudero, Camós, Vega-Garcia, Ortega, Hidalgo-Gómez, Palacio, Menéndez, Bueno, Montero, Romecín, Zazo, Alvarez, Parras, Ortega-Sabater, Chulián, Rosa, Cirillo, García, García, Manzano-Muñoz, Minguela and Fuster.

JTD Keywords: artificial intelligence, cancer registry, children, discovery, functional assay, outcomes, precision medicine, risk-factors, Artificial intelligence, B-cell precursor, Cancer registry, Functional assay, Precision medicine, Relapsed acute lymphoblastic leukemia

The incorporation of exogenous lactate into cardiac tissues is a regenerative strategy that is rapidly gaining attention. In this work, two polymeric platforms were designed to achieve a sustained release of lactate, combining immediate and prolonged release profiles. Both platforms contained electrospun poly(lactic acid) (PLA) fibers and an alginate (Alg) hydrogel. In the first platform, named L/K(x)/Alg-PLA, lactate and proteinase K (x mg of enzyme per 1 g of PLA) were directly loaded into the Alg hydrogel, into which PLA fibers were assembled. In the second platform, L/Alg-K(x)/PLA, fibers were produced by electrospinning a proteinase K:PLA solution and, subsequently, assembled within the lactate-loaded hydrogel. After characterizing the chemical, morphological, and mechanical properties of the systems, as well as their cytotoxicity, the release profiles of the two platforms were determined considering different amounts of proteinase K (x = 5.2, 26, and 52 mg of proteinase K per 1 g of PLA), which is known to exhibit a broad cleavage activity. The profiles obtained using L/Alg-K(x)/PLA platforms with x = 26 and 52 were the closest to the criteria that must be met for cardiac tissue regeneration. Finally, the amount of lactate directly loaded in the Alg hydrogel for immediate release and the amount of protein in the electrospinning solution were adapted to achieve a constant lactate release of around 6 mM per day over 1 or 2 weeks. In the optimized bioplatform, in which 6 mM lactate was loaded in the hydrogel, the amount of fibers was increased by a factor of x3, the amount of enzyme was adjusted to 40 mg per 1 g of PLA, and a daily lactate release of 5.9 +/- 2.7 mM over a period of 11 days was achieved. Accordingly, the engineered device fully satisfied the characteristics and requirements for heart tissue regeneration.

JTD Keywords: biodegradable fibers, cardiac tissue regeneration, cell, drug-release, elastic-modulus, electrospinning, heart, nanoindentation, plasma treatment, proteinase, scaffold, stiffness, Alginate, Alginates, Biodegradable fibers, Cardiac tissue, Cardiac tissue regeneration, Cell, Delayed-action preparations, Drug-release, Elastic-modulus, Electrospinning, Endopeptidase k, Heart, Hydrogels, Lactic acid, Nanoindentation, Plasma treatment, Poly(lactide), Polyesters, Proteinase, Regeneration, Scaffold, Skeletal-muscle, Stiffness

Since the emergence of 3D bioprinting technology, both synthetic and natural materials have been used to develop bioinks for producing cell-laden cardiac grafts. To this end, extracellular-matrix (ECM)-derived hydrogels can be used to develop scaffolds that closely mimic the complex 3D environments for cell culture. This study presents a novel cardiac bioink based on hydrogels exclusively derived from decellularized porcine myocardium loaded with human-bone-marrow-derived mesenchymal stromal cells. Hence, the hydrogel can be used to develop cell-laden cardiac patches without the need to add other biomaterials or use additional crosslinkers. The scaffold ultrastructure and mechanical properties of the bioink were characterized to optimize its production, specifically focusing on the matrix enzymatic digestion time. The cells were cultured in 3D within the developed hydrogels to assess their response. The results indicate that the hydrogels fostered inter-cell and cell-matrix crosstalk after 1 week of culture. In conclusion, the bioink developed and presented in this study holds great potential for developing cell-laden customized patches for cardiac repair.

JTD Keywords: biology, biomaterials, collagen, decellularized cardiac tissue, extracellular matrix, hydrogels, mesenchymal stromal cells, 3d bioprinting, Biomaterials, Decellularized cardiac tissue, Extracellular matrix, Hydrogels, Mesenchymal stem-cells, Mesenchymal stromal cells

There is a growing interest in developing natural hydrogel-based scaffolds to culture cells in a three-dimensional (3D) millieu that better mimics the in vivo cells' microenvironment. A promising approach is to use hydrogels from animal tissues, such as decellularized extracellular matrices; however, they usually exhibit suboptimal mechanical properties compared to native tissue and their composition with hundreds of different protein complicates to elucidate which stimulus triggers cell's responses. As simpler scaffolds, type I collagen hydrogels are used to study cell behavior in mechanobiology even though they are also softer than native tissues. In this work, type I collagen is mixed with bacterial nanocellulose fibers (BCf) to develop reinforced scaffolds with mechanical properties suitable for 3D cell culture. BCf were produced from blended pellicles biosynthesized from Komagataeibacter xylinus. Then, BCf were mixed with concentrated collagen from rat-tail tendons to form composite hydrogels. Confocal laser scanning microscopy and scanning electron microscopy images confirmed the homogeneous macro- and microdistribution of both natural polymers. Porosity analysis confirmed that BCf do not disrupt the scaffold structure. Tensile strength and rheology measurements demonstrated the reinforcement action of BCf (43% increased stiffness) compared to the collagen hydrogel while maintaining the same viscoelastic response. Additionally, this reinforcement of collagen hydrogels with BCf offers the possibility to mix cells before gelation and then proceed to the culture of the 3D cell scaffolds. We obtained scaffolds with human bone marrow-derived mesenchymal stromal cells or human fibroblasts within the composite hydrogels, allowing a homogeneous 3D viable culture for at least 7 days. A smaller surface shrinkage in the reinforced hydrogels compared to type I collagen hydrogels confirmed the strengthening of the composite hydrogels. These collagen hydrogels reinforced with BCf might emerge as a promising platform for 3D in vitro organ modeling, tissue-engineering applications, and suitable to conduct fundamental mechanobiology studies.

JTD Keywords: 3d cell culture, bacterial cellulose, collagen, composite hydrogels, 3d cell culture, Bacterial cellulose, Cellulose/collagen composite, Collagen, Composite hydrogels, Contraction, Cross-linking, Cytocompatibility, Fibroblasts, Matrix, Mechanical-properties, Reinforcement, Stiffness, Tissue engineering

Three dimensional (3D) bioprinting is an emerging technology that enables complex spatial modeling of cell-based tissue engineering products, whose therapeutic potential in regenerative medicine is enormous. However, its success largely depends on the definition of a bioprintable zone, which is specific for each combination of cell-loaded hydrogels (or bioinks) and scaffolds, matching the mechanical and biological characteristics of the target tissue to be repaired. Therefore proper adjustment of the bioink formulation requires a compromise between: (i) the maintenance of cellular critical quality attributes (CQA) within a defined range of specifications to cell component, and (ii) the mechanical characteristics of the printed tissue to biofabricate. Herein, we investigated the advantages of using natural hydrogel-based bioinks to preserve the most relevant CQA in bone tissue regeneration applications, particularly focusing on cell viability and osteogenic potential of multipotent mesenchymal stromal cells (MSCs) displaying tripotency in vitro, and a phenotypic profile of 99.9% CD105(+)/CD45,(-) 10.3% HLA-DR,(+) 100.0% CD90,(+) and 99.2% CD73(+)/CD31(-) expression. Remarkably, hyaluronic acid, fibrin, and gelatin allowed for optimal recovery of viable cells, while preserving MSC's proliferation capacity and osteogenic potency in vitro. This was achieved by providing a 3D structure with a compression module below 8.8 +/- 0.5 kPa, given that higher values resulted in cell loss by mechanical stress. Beyond the biocompatibility of naturally occurring polymers, our results highlight the enhanced protection on CQA exerted by bioinks of natural origin (preferably HA, gelatin, and fibrin) on MSC, bone marrow during the 3D bioprinting process, reducing shear stress and offering structural support for proliferation and osteogenic differentiation.

JTD Keywords: critical quality attributes, human mesenchymal stromal cells, osteogenic differentiation, potency, substances of human origin (soho), 3d bioprinting, Critical quality attributes, Human mesenchymal stromal cells, Osteogenic differentiation, Potency, Stem-cells, Substances of human origin (soho)

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

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

Gap junction channels (GJCs) mediate intercellular communication by connecting two neighbouring cells and enabling direct exchange of ions and small molecules. Cell coupling via connexin-43 (Cx43) GJCs is important in a wide range of cellular processes in health and disease (Churko and Laird, 2013; Liang et al., 2020; Poelzing and Rosenbaum, 2004), yet the structural basis of Cx43 function and regulation has not been determined until now. Here, we describe the structure of a human Cx43 GJC solved by cryo-EM and single particle analysis at 2.26 Å resolution. The pore region of Cx43 GJC features several lipid-like densities per Cx43 monomer, located close to a putative lateral access site at the monomer boundary. We found a previously undescribed conformation on the cytosolic side of the pore, formed by the N-terminal domain and the transmembrane helix 2 of Cx43 and stabilized by a small molecule. Structures of the Cx43 GJC and hemichannels (HCs) in nanodiscs reveal a similar gate arrangement. The features of the Cx43 GJC and HC cryo-EM maps and the channel properties revealed by molecular dynamics simulations suggest that the captured states of Cx43 are consistent with a closed state.© 2023, Qi, Acosta Gutierrez et al.

JTD Keywords: cryo-em, dehydroepiandrosterone dhea, expression, gap junction channel, gene, gja1 mutations, hemichannel, membrane protein, phenotype, protein, structure, system, visualization, Biochemistry, Chemical biology, Connexin-43, Cryo-em, Gap junction channel, Hemichannel, Human, Membrane protein, Molecular biophysics, Oculodentodigital dysplasia, Structural biology, Structure

The formation of a biological seal around the neck of titanium (Ti) implants is critical for ensuring integration at the gingival site and for preventing bacterial colonization that may lead to periimplantitis. This process is guided by activated fibroblasts, named myofibroblasts, which secrete extracellular matrix (ECM) proteins and ECM-degrading enzymes resolving the wound. However, in some cases, Ti is not able to attract and activate fibroblasts to a sufficient extent, which may compromise the success of the implant. Fibronectin (FN) is an ECM component found in wounds that is able to guide soft tissue healing through the adhesion of cells and attraction of growth factors (GFs). However, clinical use of FN functionalized Ti implants is problematic because FN is difficult to obtain, and is sensitive to degradation. Herein, functionalizing Ti with a modified recombinant heparin binding II (HBII) domain of FN, mutated to include an Arg-Gly-Asp (RGD) sequence for promoting both fibroblast adhesion and GF attraction, is aimed at. The HBII-RGD domain is able to stimulate fibroblast adhesion, spreading, proliferation, migration, and activation to a greater extent than the native HBII, reaching values closer to those of full-length FN suggesting that it might induce the formation of a biological sealing.© 2023 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.

JTD Keywords: alpha-4-beta-1, beta, cell-binding, collagen, extracellular-matrix, fibroblast activation, fibronectin, growth factors, integrins, metalloproteinases, myofibroblasts, proliferation, soft-tissue integration, titanium, Biological-activities, Fibroblast activation, Titanium

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

The Bin/amphiphysin/Rvs (BAR) superfamily proteins have a crescent binding domain and bend biomembranes along the domain axis. However, their anisotropic bending rigidities and spontaneous curvatures have not been experimentally determined. Here, we estimated these values from the bound protein densities on tethered vesicles using a mean-field theory of anisotropic bending energy and orientation-dependent excluded volume. The dependence curves of the protein density on the membrane curvature are fitted to the experimental data for the I-BAR and N-BAR domains reported by C. Prevost et al. Nat. Commun., 2015, 6, 8529 and F.-C. Tsai et al. Soft Matter, 2021, 17, 4254-4265, respectively. For the I-BAR domain, all three density curves of different chemical potentials exhibit excellent fits with a single parameter set of anisotropic bending energy. When the classical isotropic bending energy is used instead, one of the curves can be fitted well, but the others exhibit large deviations. In contrast, for the N-BAR domain, two curves are not well fitted simultaneously the anisotropic model, although it is significantly improved compared to the isotropic model. This deviation likely suggests a cluster formation of the N-BAR domains.

JTD Keywords: Membrane-mediated interactions,elastic properties,bar,shape,mechanisms,inclusions,generation,polymers,driven,bod

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

The mutual interaction between reactive species generated by non-thermal plasma and biopolymers in solution causes oxidative modifications that can have an impact in biomedical applications.

JTD Keywords: atmospheric plasma, cellulose, dftb3, gas, oxidation, parameterization, simulations, water, Biopolymers, Hydrogen peroxide, Molecular dynamics simulation, Molecular-dynamics, Nitrites, Reactive oxygen species

The function of organs such as lungs, kidneys and mammary glands relies on the three-dimensional geometry of their epithelium. To adopt shapes such as spheres, tubes and ellipsoids, epithelia generate mechanical stresses that are generally unknown. Here we engineer curved epithelial monolayers of controlled size and shape and map their state of stress. We design pressurized epithelia with circular, rectangular and ellipsoidal footprints. We develop a computational method, called curved monolayer stress microscopy, to map the stress tensor in these epithelia. This method establishes a correspondence between epithelial shape and mechanical stress without assumptions of material properties. In epithelia with spherical geometry we show that stress weakly increases with areal strain in a size-independent manner. In epithelia with rectangular and ellipsoidal cross-section we find pronounced stress anisotropies that impact cell alignment. Our approach enables a systematic study of how geometry and stress influence epithelial fate and function in three-dimensions.© 2023. The Author(s).

JTD Keywords: cell, forces, morphogenesis, tension, E-cadherin, Epithelial cells, Epithelium, Microscopy, Stress, mechanical

Sequencing has revealed hundreds of millions of human genetic variants, and continued efforts will only add to this variant avalanche. Insufficient information exists to interpret the effects of most variants, limiting opportunities for precision medicine and comprehension of genome function. A solution lies in experimental assessment of the functional effect of variants, which can reveal their biological and clinical impact. However, variant effect assays have generally been undertaken reactively for individual variants only after and, in most cases long after, their first observation. Now, multiplexed assays of variant effect can characterise massive numbers of variants simultaneously, yielding variant effect maps that reveal the function of every possible single nucleotide change in a gene or regulatory element. Generating maps for every protein encoding gene and regulatory element in the human genome would create an 'Atlas' of variant effect maps and transform our understanding of genetics and usher in a new era of nucleotide-resolution functional knowledge of the genome. An Atlas would reveal the fundamental biology of the human genome, inform human evolution, empower the development and use of therapeutics and maximize the utility of genomics for diagnosing and treating disease. The Atlas of Variant Effects Alliance is an international collaborative group comprising hundreds of researchers, technologists and clinicians dedicated to realising an Atlas of Variant Effects to help deliver on the promise of genomics.

JTD Keywords: functional genomics, genome interpretation, global alliance, multiplexed assay of variant effect, saturation mutagenesis, Functional genomics, Genome interpretation, Global alliance, Multiplexed assay of variant effect, Saturation mutagenesis, Variant effect

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

Previous studies have shown hydrophilic/hydrophobic implant surfaces stimulate/hinder osseointegration. An analogous concept was applied here using common biological functional groups on a model surface to promote oral keratinocytes (OKs) proliferation and hemidesmosomes (HD) to extend implant lifespans through increased soft tissue attachment. However, it is unclear what physicochemistry stimulates HDs. Thus, common biological functional groups (NH2 , OH, and CH3 ) were functionalized on glass using silanization. Non-functionalized plasma-cleaned glass and H silanization were controls. Surface modifications were confirmed with X-ray photoelectron spectroscopy and water contact angle. The amount of bovine serum albumin (BSA) and fibrinogen, and BSA thickness, were assessed to understand how adsorbed protein properties were influenced by physicochemistry and may influence HDs. OKs proliferation was measured, and HDs were quantified with immunofluorescence for collagen XVII and integrin β4. Plasma-cleaned surfaces were the most hydrophilic group overall, while CH3 was the most hydrophobic and OH was the most hydrophilic among functionalized groups. Modification with the OH chemical group showed the highest OKs proliferation and HD expression. The OKs response on OH surfaces appeared to not correlate to the amount or thickness of adsorbed model proteins. These results reveal relevant surface physicochemical features to favor HDs and improve implant soft tissue attachment.© 2023 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals LLC.

JTD Keywords: attachment, chemistry, collagen, differentiation, epithelial-cells, hemidesmosome, implant, in-vitro, integrin, keratinocyte, mechanism, organosilane, physicochemistry, protein adsorption, Attachment, Cell-adhesion, Physicochemistry

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

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

The functionalization of 3D-printed poly-l-lactic acid (PLLA) and poly(l-lactic-co-ε-caprolactone) (PLCL) bioresorbable stents has been successfully achieved with linear RGDS and YIGSR peptides, as well as a dual platform containing both motifs within a single biomolecule.

JTD Keywords: adsorbed fibrinogen, chemistry, endothelialization, immobilization, platelets, plla, selectivity, surface, titanium, Absorbable implants, Cell adhesion, Endothelial cells, In-vitro hemocompatibility, Peptides, Polymers, Printing, three-dimensional, Stents, Tyrosyl-isoleucyl-glycyl-seryl-arginine

Regeneration after a peripheral nerve injury still remains a challenge, due to the limited regenerative potential of axons after injury. While the endocannabinoid system (ECS) has been widely studied for its neuroprotective and analgesic effects, its role in axonal regeneration and during the conditioning lesion remains unexplored. In this study, we observed that a peripheral nerve injury induces axonal regeneration through an increase in the endocannabinoid tone. We also enhanced the regenerative capacity of dorsal root ganglia (DRG) neurons through the inhibition of endocannabinoid degradative enzyme MAGL or a CB1R agonist. Our results suggest that the ECS, via CB1R and PI3K-pAkt pathway activation, plays an important role in promoting the intrinsic regenerative capacity of sensory neurons after injury.© 2023 The Author(s).

JTD Keywords: brain, gene-expression, lesion, nerve, receptors, targets, Clinical neuroscience, Drugs, Endogenous cannabinoid system, Molecular medicine

Carbon-13 hyperpolarized pyruvate is about to become the next-generation contrast agent for molecular magnetic resonance imaging of cancer and other diseases. Here, efficient and rapid pyruvate hyperpolarization is achieved via signal amplification by reversible exchange (SABRE) with parahydrogen through synergistic use of substrate deuteration, alternating, and static microtesla magnetic fields. Up to 22 and 6% long-lasting 13C polarization (T1 = 3.7 ± 0.25 and 1.7 ± 0.1 min) is demonstrated for the C1 and C2 nuclear sites, respectively. The remarkable polarization levels become possible as a result of favorable relaxation dynamics at the microtesla fields. The ultralong polarization lifetimes will be conducive to yielding high polarization after purification, quality assurance, and injection of the hyperpolarized molecular imaging probes. These results pave the way to future in vivo translation of carbon-13 hyperpolarized molecular imaging probes prepared by this approach.

JTD Keywords: hydrogen, nmr, Carbon isotopes, Carbon-13, Magnetic resonance imaging, Magnetic resonance spectroscopy, Pyruvic acid, Sabre

Immunoassays show great potential for the detection of low levels of cytokines, due to their high sensitivity and excellent specificity. There is a particular demand for biosensors that enable both high-throughput screening and continuous monitoring of clinically relevant cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα). To this end, we here introduce a novel bioluminescent immunoassay based on the ratiometric plug-and-play immunodiagnostics (RAPPID) platform, with an improved intrinsic signal-to-background and an >80-fold increase in the luminescent signal. The new dRAPPID assay, comprising a dimeric protein G adapter connected via a semiflexible linker, was applied to detect the secretion of IL-6 by breast carcinoma cells upon TNFα stimulation and the production of low concentrations of IL-6 (∼18 pM) in an endotoxin-stimulated human 3D muscle tissue model. Moreover, we integrated the dRAPPID assay in a newly developed microfluidic device for the simultaneous and continuous monitoring of changes in IL-6 and TNFα in the low-nanomolar range. The luminescence-based read-out and the homogeneous nature of the dRAPPID platform allowed for detection with a simple measurement setup, consisting of a digital camera and a light-sealed box. This permits the usage of the continuous dRAPPID monitoring chip at the point of need, without the requirement for complex or expensive detection techniques.

JTD Keywords: cells, code, elisa, il-6, inflammation, kits, pathogenesis, procalcitonin, release, Cytokines, Humans, Immunoassay, Immunologic tests, Interleukin-6, Tumor necrosis factor-alpha

JTD Keywords: 3d printing, Biodegradable, Guided bone regeneration, Implant

Sprouting angiogenesis is a core biological process critical to vascular development. Its accurate simulation, relevant to multiple facets of human health, is of broad, interdisciplinary appeal. This study presents an in-silico model replicating a microfluidic assay where endothelial cells sprout into a biomimetic extracellular matrix, specifically, a large-pore, low-concentration fibrin-based porous hydrogel, influenced by chemotactic factors. We introduce a novel approach by incorporating the extracellular matrix and chemotactic factor effects into a unified term using a single parameter, primarily focusing on modelling sprouting dynamics and morphology. This continuous model naturally describes chemotactic-induced sprouting with no need for additional rules. In addition, we extended our base model to account for matrix sensing and degradation, crucial aspects of angiogenesis. We validate our model via a hybrid in-silico experimental method, comparing the model predictions with experimental results derived from the microfluidic setup. Our results underscore the intricate relationship between the extracellular matrix structure and angiogenic sprouting, proposing a promising method for predicting the influence of the extracellular matrix on angiogenesis.Copyright © 2023 Ferre-Torres, Noguera-Monteagudo, Lopez-Canosa, Romero-Arias, Barrio, Castaño and Hernandez-Machado.

JTD Keywords: angiogenesis, biomimmetic, chemotaxis, endothelial cells, filopodia, growth, in silico model, mathematical models, mechanisms, metalloproteinase, migration, morphogenesis, phase field, pore-size, simulation, Angiogenesis, Biomimmetic, Chemotaxis, Endothelial cells, Extracellular matrix, In silico model, Mathematical models, Phase field, Tip cells

Titanium implantation success may be compromised by Staphylococcus aureus surface colonization and posterior infection. To avoid this issue, different strategies have been investigated to promote an antibacterial character to titanium. In this work, two antibacterial agents (silver nanoparticles and a multifunctional antimicrobial peptide) were used to coat titanium surfaces. The modulation of the nanoparticle (≈32.1 ± 9.4 nm) density on titanium could be optimized, and a sequential functionalization with both agents was achieved through a two-step functionalization method by means of surface silanization. The antibacterial character of the coating agents was assessed individually as well as combined. The results have shown that a reduction in bacteria after 4 h of incubation can be achieved on all the coated surfaces. After 24 h of incubation, however, the individual antimicrobial peptide coating was more effective than the silver nanoparticles or their combination against Staphylococcus aureus. All tested coatings were non-cytotoxic for eukaryotic cells.

JTD Keywords: antimicrobial peptide, biomaterials, bone, coatings, performance, ph, resistance, silanization, silver nanoparticles, staphylococcus aureus, Anti-bacterial agents, Antimicrobial peptide, Coated materials, biocompatible, Metal nanoparticles, Reduces bacterial adhesion, Silanization, Silver, Silver nanoparticles, Staphylococcus aureus, Surface properties, Titanium, Titanium functionalization

The bacterium Pseudomonas aeruginosa is involved in chronic infections of cystic fibrosis lungs and chronic wounds. In these infections the bacteria are present as aggregates suspended in host secretions. During the course of the infections there is a selection for mutants that overproduce exopolysaccharides, suggesting that the exopolysaccharides play a role in the persistence and antibiotic tolerance of the aggregated bacteria. Here, we investigated the role of individual P. aeruginosa exopolysaccharides in aggregate-associated antibiotic tolerance. We employed an aggregate-based antibiotic tolerance assay on a set of P. aeruginosa strains that were genetically engineered to over-produce a single, none, or all of the three exopolysaccharides Pel, Psl, and alginate. The antibiotic tolerance assays were conducted with the clinically relevant antibiotics tobramycin, ciprofloxacin and meropenem. Our study suggests that alginate plays a role in the tolerance of P. aeruginosa aggregates toward tobramycin and meropenem, but not ciprofloxacin. However, contrary to previous studies we did not observe a role for Psl or Pel in the tolerance of P. aeruginosa aggregates toward tobramycin, ciprofloxacin, and meropenem.Copyright © 2023 Liang, Nilsson, Kragh, Hedal, Alcàcer-Almansa, Kiilerich, Andersen and Tolker-Nielsen.

JTD Keywords: aggregates, antibiotic tolerance, biofilm formation, extracellular matrix, genome, growth, lungs, molecular-mechanisms, mutations, polysaccharide, pseudomonas aeruginosa, psl, system, Aggregates, Antibiotic tolerance, Biofilm, Extracellular matrix, Pseudomonas aeruginosa, Small-colony variants

Mimicking bone extracellular matrix (ECM) is paramount to develop novel biomaterials for bone tissue engineering. In this regard, the combination of integrin-binding ligands together with osteogenic peptides represents a powerful approach to recapitulate the healing microenvironment of bone. In the present work, we designed polyethylene glycol (PEG)-based hydrogels functionalized with cell instructive multifunctional biomimetic peptides (either with cyclic RGD-DWIVA or cyclic RGD-cyclic DWIVA) and cross-linked with matrix metalloproteinases (MMPs)-degradable sequences to enable dynamic enzymatic biodegradation and cell spreading and differentiation. The analysis of the intrinsic properties of the hydrogel revealed relevant mechanical properties, porosity, swelling and degradability to engineer hydrogels for bone tissue engineering. Moreover, the engineered hydrogels were able to promote human mesenchymal stem cells (MSCs) spreading and significantly improve their osteogenic differentiation. Thus, these novel hydrogels could be a promising candidate for applications in bone tissue engineering, such as acellular systems to be implanted and regenerate bone or in stem cells therapy.Copyright © 2023 Oliver-Cervelló, Martin-Gómez, Gonzalez-Garcia, Salmeron-Sanchez, Ginebra and Mas-Moruno.

JTD Keywords: biomaterials, cross-linking, dwiva, functionalization, hydrogel, integrin, kinetics, marrow stromal cells, matrices, multifunctionality, myogenic differentiation, osteogenic differentiation, regeneration, stem-cells, Biomimetic peptides, Dwiva, Functionalization, Hydrogel, Multifunctionality, Osteogenic differentiation, Poly(ethylene glycol) hydrogels

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

(Phospho)proteomics of old-aged subjects without cognitive or behavioral symptoms, and without AD-neuropathological changes and lacking any other neurodegenerative alteration will increase understanding about the physiological state of human brain aging without associate neurological deficits and neuropathological lesions.(Phospho)proteomics using conventional label-free- and SWATH-MS (Sequential window acquisition of all theoretical fragment ion spectra mass spectrometry) has been assessed in the frontal cortex (FC) of individuals without NFTs, senile plaques (SPs) and age-related co-morbidities classified by age (years) in four groups; group 1 (young, 30-44); group 2 (middle-aged: MA, 45-52); group 3 (early-elderly, 64-70); and group 4 (late-elderly, 75-85).Protein levels and deregulated protein phosphorylation linked to similar biological terms/functions, but involving different individual proteins, are found in FC with age. The modified expression occurs in cytoskeleton proteins, membranes, synapses, vesicles, myelin, membrane transport and ion channels, DNA and RNA metabolism, ubiquitin-proteasome-system (UPS), kinases and phosphatases, fatty acid metabolism, and mitochondria. Dysregulated phosphoproteins are associated with the cytoskeleton, including microfilaments, actin-binding proteins, intermediate filaments of neurons and glial cells, and microtubules; membrane proteins, synapses, and dense core vesicles; kinases and phosphatases; proteins linked to DNA and RNA; members of the UPS; GTPase regulation; inflammation; and lipid metabolism. Noteworthy, protein levels of large clusters of hierarchically-related protein expression levels are stable until 70. However, protein levels of components of cell membranes, vesicles and synapses, RNA modulation, and cellular structures (including tau and tubulin filaments) are markedly altered from the age of 75. Similarly, marked modifications occur in the larger phosphoprotein clusters involving cytoskeleton and neuronal structures, membrane stabilization, and kinase regulation in the late elderly.Present findings may increase understanding of human brain proteostasis modifications in the elderly in the subpopulation of individuals not having AD neuropathological change and any other neurodegenerative change in any telencephalon region.

JTD Keywords: (phospho)proteomics, cortex, cytoskeleton, hippocampus, kinases, membranes, mitochondria, mitochondrial-function, pathological process, phosphoproteome analysis, phosphorylation, proteome, quantitative proteomics, synapsis, tau-protein, therapeutic target, (phospho)proteomics, Aged, Alzheimer disease, Brain, Brain aging, Cytoskeleton, Humans, Kinases, Membranes, Middle aged, Mitochondria, Nervous system diseases, Neurodegenerative diseases, Neurons, Phosphoric monoester hydrolases, Proteome, Synapsis, Tau proteins

Previously, functional coatings on 3D-printed titanium implants were developed to improve their biointegration by separately incorporating Ga and Ag on the biomaterial surface. Now, a thermochemical treatment modification is proposed to study the effect of their simultaneous incorporation. Different concentrations of AgNO3 and Ga(NO3)3 are evaluated, and the obtained surfaces are completely characterized. Ion release, cytotoxicity, and bioactivity studies complement the characterization. The provided antibacterial effect of the surfaces is analyzed, and cell response is assessed by the study of SaOS-2 cell adhesion, proliferation, and differentiation. The Ti surface doping is confirmed by the formation of Ga-containing Ca titanates and nanoparticles of metallic Ag within the titanate coating. The surfaces generated with all combinations of AgNO3 and Ga(NO3)3 concentrations show bioactivity. The bacterial assay confirms a strong bactericidal impact achieved by the effect of both Ga and Ag present on the surface, especially for Pseudomonas aeruginosa, one of the main pathogens involved in orthopedic implant failures. SaOS-2 cells adhere and proliferate on the Ga/Ag-doped Ti surfaces, and the presence of gallium favors cell differentiation. The dual effect of both metallic agents doping the titanium surface provides bioactivity while protecting the biomaterial from the most frequent pathogens in implantology.

JTD Keywords: 3d-printing, agent, antibacterial activity, bioactive ti, biomaterials, coatings, competition, cu, gallium, glasses, ions, metal, porous structures, promote osseointegration, silver, titanium implants, In-vitro, Porous structures, Titanium implants

The hippocampus of cases with neurofibrillary tangles (NFT) pathology classified as stages I–II, III–IV, and V–VI without comorbidities, and middle-aged (MA) individuals with no NFT pathology, were examined to learn about the composition of granulovacuolar degeneration (GVD). Our results confirm the presence of CK1-?, p38-P Thr180/Tyr182, SAPK/JNK-P Thr183/Thr185, GSK-3?/?-P Tyr279/Tyr216, and GSK-3? Ser9 in the cytoplasmic granules in a subset of neurons of the CA1 and CA2 subfields of the hippocampus. Also, we identify the presence of PKA ?/?-P Thr197, SRC-P Tyr416, PAK1-P Ser199/Ser204, CAMK2A-P Tyr197, and PKCG-P Thr655 in cytoplasmic granules in cases with NFT pathology, but not in MA cases. Our results also confirm the presence of ?-catenin-P Ser45/Thr41, IRE?-P Ser274, eIF2?-P Ser51, TDP-43-P Ser403-404 (but absent TDP-43), and ubiquitin in cytoplasmic granules. Other components of the cytoplasmic granules are MAP2-P Thr1620/1623, MAP1B-P Thr1265, ADD1-P Ser726, and ADD1/ADD1-P Ser726/Ser713, in addition to several tau species including 3Rtau, 4Rtau, and tau-P Ser262. The analysis of GVD at progressive stages of NFT pathology reveals the early appearance of phosphorylated kinases and proteins in cytoplasmic granules at stages I–II, before the appearance of pre-tangles and NFTs. Most of these granules are not surrounded by LAMP1-positive membranes. Markers of impaired ubiquitin-protesome system, abnormal reticulum stress response, and altered endocytic and autophagic pathways occur in a subpopulation of neurons containing cytoplasmic granules, and they appear later. These observations suggest early phosphorylation of kinases leading to their activation, and resulting in the abnormal phosphorylation of various substrates, including tau, as a main alteration at the first stages of GVD. © 2021 The Author(s)

JTD Keywords: alzheimer's disease, alzheimers association guidelines, alzheimer’s disease, brain aging, cyclin-dependent kinase-5, granulovacuolar degeneration, kinases, national institute, neuropathologic assessment, p38 kinase, progressive supranuclear palsy, protein phosphorylation, tau, tau pathology, up-regulation, upstream activator, Alzheimer disease, Alzheimer's disease, Alzheimer’s disease, Brain aging, Dna-binding proteins, Glycogen synthase kinase 3 beta, Glycogen-synthase kinase-3, Granulovacuolar degeneration, Hippocampus, Humans, Kinases, Middle aged, Nerve degeneration, Neurofibrillary tangles, Phosphorylation, Protein phosphorylation, Tau, Tau proteins, Ubiquitins

Different across-layer synchronization types of chimera states in multilayer networks have been discovered recently. We investigate possible relations between them, for example, if the onset of some synchronization type implies the onset of some other type. For this purpose, we use a two-layer network with multiplex inter-layer coupling. Each layer consists of a ring of non-locally coupled phase oscillators. While oscillators in each layer are identical, the layers are made non-identical by introducing mismatches in the oscillators' mean frequencies and phase lag parameters of the intra-layer coupling. We use different metrics to quantify the degree of various across-layer synchronization types. These include phase-locking between individual interacting oscillators, amplitude and phase synchronization between the order parameters of each layer, generalized synchronization between the driver and response layer, and the alignment of the incoherent oscillator groups' position on the two rings. For positive phase lag parameter mismatches, we get a cascaded onset of synchronization upon a gradual increase of the inter-layer coupling strength. For example, the two order parameters show phase synchronization before any of the interacting oscillator pairs does. For negative mismatches, most synchronization types have their onset in a narrow range of the coupling strength. Weaker couplings can destabilize chimera states in the response layer toward an almost fully coherent or fully incoherent motion. Finally, in the absence of a phase lag mismatch, sufficient coupling turns the response dynamics into a replica of the driver dynamics with the phases of all oscillators shifted by a constant lag.© 2023 Author(s). Published under an exclusive license by AIP Publishing.

JTD Keywords: chaos, Generalized synchronization

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

The term 'mechanosensation' describes the capacity of cells to translate mechanical stimuli into the coordinated regulation of intracellular signals, cellular function, gene expression and epigenetic programming. This capacity is related not only to the sensitivity of the cells to tissue motion, but also to the decryption of tissue geometric arrangement and mechanical properties. The cardiac stroma, composed of fibroblasts, has been historically considered a mechanically passive component of the heart. However, the latest research suggests that the mechanical functions of these cells are an active and necessary component of the developmental biology programme of the heart that is involved in myocardial growth and homeostasis, and a crucial determinant of cardiac repair and disease. In this Review, we discuss the general concept of cell mechanosensation and force generation as potent regulators in heart development and pathology, and describe the integration of mechanical and biohumoral pathways predisposing the heart to fibrosis and failure. Next, we address the use of 3D culture systems to integrate tissue mechanics to mimic cardiac remodelling. Finally, we highlight the potential of mechanotherapeutic strategies, including pharmacological treatment and device-mediated left ventricular unloading, to reverse remodelling in the failing heart.© 2022. Springer Nature Limited.

JTD Keywords: cardiomyocyte proliferation, cross-linking, extracellular-matrix, focal adhesions, gene-expression, mechanical regulation, myocardial-infarction, substrate stiffness affects, t-cells, Ventricular assist device

The emergence of multidrug-resistant bacteria is a serious problem worldwide. Pseudomonas aeruginosa is a pathogen that causes severe infections because it can form a biofilm that protects it from immune system mechanisms such as the production of oxidative stress. Ribonucleotide reductases are essential enzymes which synthesize deoxyribonucleotides used in the replication of DNA.

JTD Keywords: algr, biofilm, galleria mellonella, nrdj, oxidative stress, Gene-expression, Ribonucleotide reductase

JTD Keywords: deep generative models, eatris european infrastructure for translational medicine, integrative omics, machine learning, multi-omics, personalized medicine, Deep generative models, Eatris european infrastructure for translational medicine, Integrative omics, Machine learning, Multi-omics, Personalized medicine, Protein protein interaction (ppi) network

Background Pilocytic astrocytoma (PA) is the most common pediatric brain tumor and a mitogen-activated protein kinase (MAPK)-driven disease. Oncogenic MAPK-signaling drives the majority of cells into oncogene-induced senescence (OIS). While OIS induces resistance to antiproliferative therapies, it represents a potential vulnerability exploitable by senolytic agents. Methods We established new patient-derived PA cell lines that preserve molecular features of the primary tumors and can be studied in OIS and proliferation depending on expression or repression of the SV40 large T antigen. We determined expression of anti-apoptotic BCL-2 members in these models and primary PA. Dependence of senescent PA cells on anti-apoptotic BCL-2 members was investigated using a comprehensive set of BH3 mimetics. Results Senescent PA cells upregulate BCL-XL upon senescence induction and show dependency on BCL-XL for survival. BH3 mimetics with high affinity for BCL-XL (BCL-XLi) reduce metabolic activity and induce mitochondrial apoptosis in senescent PA cells at nano-molar concentrations. In contrast, BH3 mimetics without BCL-XLi activity, conventional chemotherapy, and MEK inhibitors show no effect. Conclusions Our data demonstrate that BCL-XL is critical for survival of senescent PA tumor cells and provides proof-of-principle for the use of clinically available BCL-XL-dependent senolytics.

JTD Keywords: bcl-xl, bh3 mimetics, oncogene-induced senescence, Bcl-xl, Bh3 mimetics, Expression, Family, Inhibitor, Low-grade glioma, Navitoclax, Oncogene-induced senescence, Pilocytic astrocytoma, Stem-cells

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

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

Surface curvature both emerges from, and influences the behavior of, living objects at length scales ranging from cell membranes to single cells to tissues and organs. The relevance of surface curvature in biology is supported by numerous experimental and theoretical investigations in recent years. In this review, first, a brief introduction to the key ideas of surface curvature in the context of biological systems is given and the challenges that arise when measuring surface curvature are discussed. Giving an overview of the emergence of curvature in biological systems, its significance at different length scales becomes apparent. On the other hand, summarizing current findings also shows that both single cells and entire cell sheets, tissues or organisms respond to curvature by modulating their shape and their migration behavior. Finally, the interplay between the distribution of morphogens or micro-organisms and the emergence of curvature across length scales is addressed with examples demonstrating these key mechanistic principles of morphogenesis. Overall, this review highlights that curved interfaces are not merely a passive by-product of the chemical, biological, and mechanical processes but that curvature acts also as a signal that co-determines these processes.© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.

JTD Keywords: biological systems, butterfly wing scales, cubic membranes, extracellular-matrix, geometry, mechanotransduction, membrane curvature, morphogenesis, neotissue growth, pattern-formation, soft materials, surface curvature, tissue-growth, Biological systems, Collective cell-migration, Surface curvature

Conductive and interactive hydrogels based on hyaluronic acid are engineered as wound dressings that enhance skin tissue regeneration either through electrical stimulation or by displaying multifunctional performance and, ultimately, interactivity.

JTD Keywords: antibacterial, fields, Anti-bacterial agents, Bacterial infections, Humans, Hyaluronic acid, Hydrogels, Injectable hydrogels, Skin, Wound healing

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

Fibrillar collagen structures mineralized with hydroxyapatite using the polymer-induced liquid precursor (PILP) process have been explored as synthetic models for studying biomineralization of human hard tissues and have also been applied in the fabrication of scaffolds for hard tissue regeneration. Strontium has important biological functions in bone and has been used as a therapeutic agent for treating diseases that result in bone defects, such as osteoporosis. Here, we developed a strategy to mineralize collagen with Sr-doped hydroxyapatite (HA) using the PILP process. Doping with Sr altered the crystal lattice of HA and inhibited the degree of mineralization in a concentration-dependent manner, but did not affect the unique formation of intrafibrillar minerals using the PILP. The Sr-doped HA nanocrystals were aligned in the [001] direction but did not recapitulate the parallel alignment of the c-axis of pure Ca HA in relation to the collagen fiber long axis. The mimicry of doping Sr in PILP-mineralized collagen can help understand the doping of Sr in natural hard tissues and during treatment. The fibrillary mineralized collagen with Sr-doped HA will be explored in future work as biomimetic and bioactive scaffolds for regeneration of bone and tooth dentin.

JTD Keywords: bone regeneration, osteoblast differentiation, osteoporosis, ranelate, risk, scaffolds, women, Intrafibrillar mineralization

We present a versatile method for the preparation of hyperpolarized [1-13C]fumarate as a contrast agent for preclinical in vivo MRI, using parahydrogen-induced polarization (PHIP). To benchmark this process, we compared a prototype PHIP polarizer to a state-of-the-art dissolution dynamic nuclear polarization (d-DNP) system. We found comparable polarization, volume, and concentration levels of the prepared solutions, while the preparation effort is significantly lower for the PHIP process, which can provide a preclinical dose every 10 min, opposed to around 90 min for d-DNP systems. With our approach, a 100 mM [1-13C]-fumarate solution of volumes up to 3 mL with 13-20% 13C-hyperpolarization after purification can be produced. The purified solution has a physiological pH, while the catalyst, the reaction side products, and the precursor material concentrations are reduced to nontoxic levels, as confirmed in a panel of cytotoxicity studies. The in vivo usage of the hyperpolarized fumarate as a perfusion agent in healthy mice and the metabolic conversion of fumarate to malate in tumor-bearing mice developing regions with necrotic cell death is demonstrated. Furthermore, we present a one-step synthesis to produce the 13C-labeled precursor for the hydrogenation reaction with high yield, starting from 13CO2 as a cost-effective source for 13C-labeled compounds.

JTD Keywords: Animals, Contrast media, Fumarates, Hydrogenation, Magnetic resonance imaging, Magnetic resonance spectroscopy, Mice, Para-hydrogen

Our study of pBAE polyplexes unveil their insight distribution and peptide-dependent properties. This analysis makes the gap from bench to bedside closer due to the possibility to select the most appropriate oligopeptide combination depending on the application.

JTD Keywords: gene delivery, Poly(beta-amino ester)s

Multiresponsive hydrogels, which are smart soft materials that respond to more than one external stimulus, have emerged as powerful tools for biomedical applications, such as drug delivery. Within this context and with the aim of eliminating the systematic administration of antibiotics, special attention is being paid to the development of systems for controlled delivery of antibiotic for topical treatment of bacterial infections. In this work, an electro-chemo responsive hydrogel able to release chloramphenicol (CAM), a broad spectrum antibiotic also used for anticancer therapy, is proposed. This has been prepared by grafting poly(acrylic acid) (PAA) to sodium alginate (Alg) and in situ encapsulation of poly(3,4-ethylenedioxythiophene) nanoparticles loaded with CAM (PEDOT/CAM NPs), which were obtained by emulsion polymerization. Although the response to electrical stimuli of PEDOT was the main control for the release of CAM from PEDOT/CAM NPs, the release by passive diffusion had a relatively important contribution. Conversely, the passive release of antibiotic from the whole engineered hydrogel system, Alg-g-PAA/PEDOT/CAM, was negligible, whereas significant release was achieved under electrostimulation in an acid environment. Bacterial tests and assays with cancer cells demonstrated that the biological activity of CAM remained after release by electrical stimulation. Notably, the successful dual-response of the developed hydrogel to electrical stimuli and pH changes evidence the great prospect of this smart material in the biomedical field, as a tool to fight against bacterial infections and to provide local cancer treatment.

JTD Keywords: drug-delivery, films, growth, nanoparticles, Anti-bacterial agents, Bacterial infections, Cancer stem-cells, Chloramphenicol, Humans, Hydrogels, Hydrogen-ion concentration

Introduction: Three-dimensional (3D) bioprinting is a promising technique for the development of neuronal in vitro models because it controls the deposition of materials and cells. Finding a biomaterial that supports neural differentiation in vitro while ensuring compatibility with the technique of 3D bioprinting of a self-standing construct is a challenge.Methods: In this study, gelatin methacryloyl (GelMA), methacrylated alginate (AlgMA), and hyaluronic acid (HA) were examined by exploiting their biocompatibility and tunable mechanical properties to resemble the extracellular matrix (ECM) and to create a suitable material for printing neural progenitor cells (NPCs), supporting their long-term differentiation. NPCs were printed and differentiated for up to 15 days, and cell viability and neuronal differentiation markers were assessed throughout the culture.Results and Discussion: This composite biomaterial presented the desired physical properties to mimic the ECM of the brain with high water intake, low stiffness, and slow degradation while allowing the printing of defined structures. The viability rates were maintained at approximately 80% at all time points. However, the levels of beta-III tubulin marker increased over time, demonstrating the compatibility of this biomaterial with neuronal cell culture and differentiation. Furthermore, these cells showed increased maturation with corresponding functional properties, which was also demonstrated by the formation of a neuronal network that was observed by recording spontaneous activity via Ca2+ imaging.

JTD Keywords: biomaterials, bioprinting, differentiation, in vitro models, neural progenitor cells, 2d, Biomaterials, Bioprinting, C17.2, Differentiation, Extracellular-matrix, Hydrogels, In vitro models, In-vitro, Neural progenitor cells, Neuronal models, Proliferation, Scaffolds, Stem-cells, Substrate stiffness

Lafora disease is a rare disorder caused by loss of function mutations in either the EPM2A or NHLRC1 gene. The initial symptoms of this condition are most commonly epileptic seizures, but the disease progresses rapidly with dementia, neuropsychiatric symptoms, and cognitive deterioration and has a fatal outcome within 5–10 years after onset. The hallmark of the disease is the accumulation of poorly branched glycogen in the form of aggregates known as Lafora bodies in the brain and other tissues. Several reports have demonstrated that the accumulation of this abnormal glycogen underlies all the pathologic traits of the disease. For decades, Lafora bodies were thought to accumulate exclusively in neurons. However, it was recently identified that most of these glycogen aggregates are present in astrocytes. Importantly, astrocytic Lafora bodies have been shown to contribute to pathology in Lafora disease. These results identify a primary role of astrocytes in the pathophysiology of Lafora disease and have important implications for other conditions in which glycogen abnormally accumulates in astrocytes, such as Adult Polyglucosan Body disease and the buildup of Corpora amylacea in aged brains.

JTD Keywords: abnormal glycogen, accumulation, aggregation, bodies, branching enzyme deficiency, corpora-amylacea, epilepsy, glycogen, lafora disease, mice, mouse model, neurodegeneration, neuroinflammation, progressive myoclonus epilepsy, ubiquitin ligase, Glycogen, Neuroinflammation, Polyglucosan body disease

The concept of selective tumor targeting using nanomedicines has been around for decades; however, no targeted nanoparticle has yet reached the clinic. A key bottleneck is the non-selectivity of targeted nanomedicines in vivo, which is attributed to the lack of characterization of their surface properties, especially the ligand number, thereby calling for robust techniques that allow quantifiable outcomes for an optimal design. Multivalent interactions comprise multiple copies of ligands attached to scaffolds, allowing simultaneous binding to receptors, and they play an important role in targeting. As such, 'multivalent' nanoparticles facilitate simultaneous interaction of weak surface ligands with multiple target receptors resulting in higher avidity and enhanced cell selectivity. Therefore, the study of weak binding ligands for membrane-exposed biomarkers is crucial for the successful development of targeted nanomedicines. Here we carried out a study of a cell targeting peptide known as WQP having weak binding affinity for prostate specific membrane antigen, a known prostate cancer biomarker. We evaluated the effect of its multivalent targeting using polymeric NPs over its monomeric form on the cellular uptake in different prostate cancer cell lines. We developed a method of specific enzymatic digestion to quantify the number of WQPs on NPs having different surface valencies and observed that increasing valencies resulted in a higher cellular uptake of WQP-NPs over the peptide alone. We also found that WQP-NPs showed higher uptake in PSMA over-expressing cells, attributed to a stronger avidity for selective PSMA targeting. This kind of strategy can be useful for improving the binding affinity of a weak ligand as a means for selective tumor targeting.

JTD Keywords: Cells, Delivery, Ligands, Membrane antigen, Psma

Magnetic resonance techniques are successfully utilized in a broad range of scientific disciplines and in various practical applications, with medical magnetic resonance imaging being the most widely known example. Currently, both fundamental and applied magnetic resonance are enjoying a major boost owing to the rapidly developing field of spin hyperpolarization. Hyperpolarization techniques are able to enhance signal intensities in magnetic resonance by several orders of magnitude, and thus to largely overcome its major disadvantage of relatively low sensitivity. This provides new impetus for existing applications of magnetic resonance and opens the gates to exciting new possibilities. In this review, we provide a unified picture of the many methods and techniques that fall under the umbrella term "hyperpolarization" but are currently seldom perceived as integral parts of the same field. Specifically, before delving into the individual techniques, we provide a detailed analysis of the underlying principles of spin hyperpolarization. We attempt to uncover and classify the origins of hyperpolarization, to establish its sources and the specific mechanisms that enable the flow of polarization from a source to the target spins. We then give a more detailed analysis of individual hyperpolarization techniques: the mechanisms by which they work, fundamental and technical requirements, characteristic applications, unresolved issues, and possible future directions. We are seeing a continuous growth of activity in the field of spin hyperpolarization, and we expect the field to flourish as new and improved hyperpolarization techniques are implemented. Some key areas for development are in prolonging polarization lifetimes, making hyperpolarization techniques more generally applicable to chemical/biological systems, reducing the technical and equipment requirements, and creating more efficient excitation and detection schemes. We hope this review will facilitate the sharing of knowledge between subfields within the broad topic of hyperpolarization, to help overcome existing challenges in magnetic resonance and enable novel applications.

JTD Keywords: electron-paramagnetic-resonance, high-resolution nmr, hydrogen-induced polarization, level anti-crossings, long-lived states, parahydrogen-induced polarization, photosynthetic reaction-center, reversible exchange catalysis, solid-state nmr, Dynamic-nuclear-polarization

Lately, there has been an increasing demand for materials that could improve tissue regenerative therapies and provide antimicrobial effects. Similarly, there is a growing need to develop or modify biomaterials for the diagnosis and treatment of different pathologies. In this scenario, hydroxyapatite (HAp) appears as a bioceramic with extended functionalities. Nevertheless, there are certain disadvantages related to the mechanical properties and lack of antimicrobial capacity. To circumvent them, the doping of HAp with a variety of cationic ions is emerging as a good alterative due to the different biological roles of each ion. Among many elements, lanthanides are understudied despite their great potential in the biomedical field. For this reason, the present review focuses on the biological benefits of lanthanides and how their incorporation into HAp can alter its morphology and physical properties. A comprehensive section of the applications of lanthanides-substituted HAp nanoparticles (HAp NPs) is presented to unveil the potential biomedical uses of these systems. Finally, the need to study the tolerable and non-toxic percentages of substitution with these elements is highlighted.

JTD Keywords: biolabeling, biomedicine, biosensors, bone regeneration, calcium, cancer treatment, cationic ions, cell imaging, cerium, doped hap, hydroxyapatite, implants, in-vitro bioactivity, lanthanides-substitutions, lanthanidessubstitutions, nanoparticles, radiation synovectomy, sm-153 particulate hydroxyapatite, structural-characterization, theragnostics, theranostic nanoplatforms, Europium-doped hydroxyapatite, Hydroxyapatite, Theragnostics

Peri-implantitis, caused by an inflammatory response to pathogens, is the leading cause of dental implant failure. Poor soft tissue healing surrounding implants - caused by inadequate surface properties - leads to infection, inflammation, and dysregulated keratinocyte and macrophage function. One activated inflammatory response, active around peri-implantitis compared to healthy sites, is the IL-23/IL-17A cytokine axis. Implant surfaces can be synthesized with peptide nanocoatings to present immunomodulatory motifs to target peri-implant keratinocytes to control macrophage polarization and regulate inflammatory axises toward enhancing soft tissue healing.We synthesized an IL-23 receptor (IL-23R) noncompetitive antagonist peptide nanocoating using silanization and evaluated keratinocyte secretome changes and macrophage polarization (M1-like "pro-inflammatory" vs. M2-like "pro-regenerative").IL-23R antagonist peptide nanocoatings were successfully synthesized on titanium, to model dental implant surfaces, and compared to nonfunctional nanocoatings and non-coated titanium. IL-23R antagonist nanocoatings significantly decreased keratinocyte IL-23, and downstream IL-17A, expression compared to controls. This peptide noncompetitive antagonistic function was demonstrated under lipopolysaccharide stimulation. Large scale changes in keratinocyte secretome content, toward a pro-regenerative milieu, were observed from keratinocytes cultured on the IL-23R antagonist nanocoatings compared to controls. Conditioned medium collected from keratinocytes cultured on the IL-23R antagonist nanocoatings polarized macrophages toward a M2-like phenotype, based on increased CD163 and CD206 expression and reduced iNOS expression, compared to controls.Our results support development of IL-23R noncompetitive antagonist nanocoatings to reduce the pro-inflammatory IL-23/17A pathway and augment macrophage polarization toward a pro-regenerative phenotype. Immunomodulatory implant surface engineering may promote soft tissue healing and thereby reduce rates of peri-implantitis.Copyright © 2023 Elsevier Inc. All rights reserved.

JTD Keywords: agents, alter, bioactivity, cells, dental implant, growth, keratinocyte, macrophage, peptide, peri -implant infection, peri-implant infection, Surface chemistry, Titanium

Tissue morphogenesis occurs in a complex physicochemical microenvironment with limited experimental accessibility. This often prevents a clear identification of the processes that govern the formation of a given functional shape. By applying state-of-the-art methods to minimal tissue systems, synthetic morphogenesis aims to engineer the discrete events that are necessary and sufficient to build specific tissue shapes. Here, we review recent advances in synthetic morphogenesis, highlighting how a combination of microfabrication and mechanobiology is fostering our understanding of how tissues are built.Copyright © 2022 Elsevier Ltd. All rights reserved.

JTD Keywords: cell dynamics, elongation, endothelial-cells, epithelium, growth, lumen, mechanical tension, patterns, self-organization, synthetic morphogenesis, tissue folding, tissue mechanics, topological defects, Cell dynamics, Humans, Morphogenesis, Stem-cells, Synthetic morphogenesis, Tissue folding, Tissue mechanics, Tissue shape

Many lines of evidence demonstrate a correlation between liver glycogen content and food intake. We previously demonstrated that mice overexpressing protein targeting to glycogen (PTG) specifically in the liver—which have increased glycogen content in this organ—are protected from high-fat diet (HFD)-induced obesity by reduced food intake. However, the use of PTG to increase liver glycogen implies certain limitations. PTG stimulates glycogen synthesis but also inhibits the enzyme responsible for glycogen degradation. Furthermore, as PTG is a regulatory subunit of protein phosphatase 1 (PP1), which regulates many cellular functions, its overexpression could have side effects beyond the regulation of glycogen metabolism. Therefore, it is necessary to determine whether the direct activation of glycogen synthesis, without affecting its degradation or other cellular functions, has the same effects. To this end, we generated mice overexpressing a non-inactivatable form of glycogen synthase (GS) specifically in the liver (9A-MGSAlb mice). Control and 9a-MGSAlb mice were fed a standard diet (SD) or HFD for 16 weeks. Glucose tolerance and feeding behavior were analyzed. 9A-MGSAlb mice showed an increase in hepatic glycogen in fed and fasting conditions. When fed an HFD, these animals preserved their hepatic energy state, had a reduced food intake, and presented a lower body weight and fat mass than control animals, without changes in energy expenditure. Furthermore, 9A-MGSAlb animals showed improved glucose tolerance when fed an SD or HFD. Moreover, liver triacylglycerol levels that were increased after HFD feeding were lower in these mice. These results confirm that increased liver glycogen stores contribute to decreased appetite and improve glucose tolerance in mice fed an HFD. On the basis of our findings, strategies to preserve hepatic glycogen stores emerge as potential treatments for obesity and hyperglycemia.

JTD Keywords: accumulation, atp, attenuates obesity, expression, food intake, glucose, glycogen, glycogen synthase, high-fat diet, homeostasis, hyperglycemia, liver, mgat1, muscle, protein, ptg, Glycogen, Hepatic overexpression, Liver

Biomolecular and physical cues of the extracellular matrix environment regulate collective cell dynamics and tissue patterning. Nonetheless, how the viscoelastic properties of the matrix regulate collective cell spatial and temporal organization is not fully understood. Here we show that the passive viscoelastic properties of the matrix encapsulating a spheroidal tissue of breast epithelial cells guide tissue proliferation in space and in time. Matrix viscoelasticity prompts symmetry breaking of the spheroid, leading to the formation of invading finger-like protrusions, YAP nuclear translocation and epithelial-to-mesenchymal transition both in vitro and in vivo in a Arp2/3-complex-dependent manner. Computational modelling of these observations allows us to establish a phase diagram relating morphological stability with matrix viscoelasticity, tissue viscosity, cell motility and cell division rate, which is experimentally validated by biochemical assays and in vitro experiments with an intestinal organoid. Altogether, this work highlights the role of stress relaxation mechanisms in tissue growth dynamics, a fundamental process in morphogenesis and oncogenesis.© 2022. The Author(s), under exclusive licence to Springer Nature Limited.

JTD Keywords: in-vitro, migration, morphogenesis, stiffness, Elasticity, Epithelial cells, Extracellular matrix, Intestinal stem-cell, Viscosity

Prion-like domains (PrLDs) are intrinsically disordered regions (IDRs) of low sequence complexity with a similar composition to yeast prion domains. PrLDs-containing proteins have been involved in different organisms' regulatory processes. Regions of moderate amyloid propensity within IDRs have been shown to assemble autonomously into amyloid fibrils. These sequences tend to be rich in polar amino acids and often escape from the detection of classical bioinformatics screenings that look for highly aggregation-prone hydrophobic sequence stretches. We defined them as cryptic amyloidogenic regions (CARs) and recently developed an integrated database that collects thousands of predicted CARs in IDRs. CARs seem to be evolutionary conserved among disordered regions because of their potential to stablish functional contacts with other biomolecules. Here we have focused on identifying and characterizing CARs in prion-like proteins (pCARs) from plants, a lineage that has been poorly studied in comparison with other prionomes. We confirmed the intrinsic amyloid potential for a selected pCAR from Arabidopsis thaliana and explored functional enrichments and compositional bias of pCARs in plant prion-like proteins.Copyright © 2023 Pintado-Grima, Santos, Iglesias, Manglano-Artuñedo, Pallarès and Ventura.

JTD Keywords: aggregation, aromatic residues, bioinformatics, domains, functional interactions, identify proteins, plants, prediction, prion-like domains, q/n-rich, regulator, sup35, yeast, Bioinformatics, Cryptic amyloidogenic regions, Functional interactions, Plants, Prion-like domains, Rna-binding proteins

The extracellular matrix (ECM) of the lung is a filamentous network composed mainly of collagens, elastin, and proteoglycans that provides structural and physical support to its populating cells. Proliferation, migration and overall behaviour of those cells is greatly determined by micromechanical queues provided by the ECM. Lung fibrosis displays an aberrant increased deposition of ECM which likely changes filament organization and stiffens the ECM, thus upregulating the profibrotic profile of pulmonary cells. We have previously used AFM to assess changes in the Young’s Modulus (E) of the ECM in the lung. Here, we perform further ECM topographical, mechanical and viscoelastic analysis at the micro- and nano-scale throughout fibrosis development. Furthermore, we provide nanoscale correlations between topographical and elastic properties of the ECM fibres. Firstly, we identify a softening of the ECM after rats are instilled with media associated with recovery of mechanical homeostasis, which is hindered in bleomycin-instilled lungs. Moreover, we find opposite correlations between fibre stiffness and roughness in PBS- vs bleomycin-treated lung. Our findings suggest that changes in ECM nanoscale organization take place at different stages of fibrosis, with the potential to help identify pharmacological targets to hinder its progression.

JTD Keywords: atomic force microscopy, cells, deposition, extracellular matrix, idiopathic pulmonary fibrosis, mechanisms, mechanosensing, membranes, micromechanical properties, pathogenesis, stiffness, tissues, viscoelasticity, Extracellular matrix, Induced lung fibrosis, Mechanosensing

Background: Patients with obstructive sleep apnea (OSA) experience recurrent hypoxemic events with a frequency sometimes exceeding 60 events/h. These episodic events induce downstream transient hypoxia in the parenchymal tissue of all organs, thereby eliciting the pathological consequences of OSA. Whereas experimental models currently apply intermittent hypoxia to cells conventionally cultured in 2D plates, there is no well-characterized setting that will subject cells to well-controlled intermittent hypoxia in a 3D environment and enable the study of the effects of OSA on the cells of interest while preserving the underlying tissue environment.Aim: To design and characterize an experimental approach that exposes cells to high-frequency intermittent hypoxia mimicking OSA in 3D (hydrogels or tissue slices).Methods: Hydrogels made from lung extracellular matrix (L-ECM) or brain tissue slices (300-800-mu m thickness) were placed on a well whose bottom consisted of a permeable silicone membrane. The chamber beneath the membrane was subjected to a square wave of hypoxic/normoxic air. The oxygen concentration at different depths within the hydrogel/tissue slice was measured with an oxygen microsensor.Results: 3D-seeded cells could be subjected to well-controlled and realistic intermittent hypoxia patterns mimicking 60 apneas/h when cultured in L-ECM hydrogels & AP;500 mu m-thick or ex-vivo in brain slices 300-500 mu m-thick.Conclusion: This novel approach will facilitate the investigation of the effects of intermittent hypoxia simulating OSA in 3D-residing cells within the parenchyma of different tissues/organs.

JTD Keywords: 3d culture, cell culture, diffusion, disease model, hydrogels, hypoxia, model, oxygen diffusion, tissue slice, transport, 3d culture, Cell culture, Disease model, Hydrogels, Hypoxia, Obstructive sleep apnea, Oxygen, Oxygen diffusion, Tissue slice

Mycobacterium brumae is a rapid-growing, non-pathogenic Mycobacterium species, originally isolated from environmental and human samples in Barcelona, Spain. Mycobacterium brumae is not pathogenic and it's in vitro phenotype and immunogenic properties have been well characterized. However, the knowledge of its underlying genetic composition is still incomplete. In this study, we first describe the 4 Mb genome of the M. brumae type strain ATCC 51384T assembling PacBio reads, and second, we assess the low intraspecies variability by comparing the type strain with Illumina reads from three additional strains. Mycobacterium brumae genome is composed of a circular chromosome with a high GC content of 69.2% and containing 3,791 CDSs, 97 pseudogenes, one prophage and no CRISPR loci. Mycobacterium brumae has shown no pathogenic potential in in vivo experiments, and our genomic analysis confirms its phylogenetic position with other non-pathogenic and rapid growing mycobacteria. Accordingly, we determined the absence of virulence-related genes, such as ESX-1 locus and most PE/PPE genes, among others. Although the immunogenic potential of M. brumae was proved to be as high as Mycobacterium bovis BCG, the only mycobacteria licensed to treat cancer, the genomic content of M. tuberculosis T cell and B cell antigens in M. brumae genome is considerably lower than those antigens present in M. bovis BCG genome. Overall, this work provides relevant genomic data on one of the species of the mycobacterial genus with high therapeutic potential.Copyright © 2023 Renau-Mínguez, Herrero-Abadía, Ruiz-Rodriguez, Sentandreu, Torrents, Chiner-Oms, Torres-Puente, Comas, Julián and Coscolla.

JTD Keywords: antimicrobial susceptibility, bcg, identification, immunogenic, non-pathogenic, nontuberculous mycobacteria, resistance mechanisms, strain, therapeutic, Diversity, Immunogenic, Non-pathogenic, Nontuberculous mycobacteria, Therapeutic

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

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

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

The etiology of dental caries remains poorly understood. With the advent of next-generation sequencing, a number of studies have focused on the microbial ecology of the disease. However, taxonomic associations with caries have not been consistent. Researchers have also pursued function-centric studies of the caries microbial communities aiming to identify consistently conserved functional pathways. A major question is whether changes in microbiome are a cause or a consequence of the disease. Thus, there is a critical need to define conserved functional signatures at the onset of dental caries.Since it is unethical to induce carious lesions clinically, we developed an innovative longitudinal ex-vivo model integrated with the advanced non-invasive multiphoton second harmonic generation bioimaging to spot the very early signs of dental caries, combined with 16S rRNA short amplicon sequencing and liquid chromatography-mass spectrometry-based targeted metabolomics.For the first time, we induced longitudinally monitored caries lesions validated with the scanning electron microscope. Consequently, we spotted the caries onset and, associated with it, distinguished five differentiating metabolites - Lactate, Pyruvate, Dihydroxyacetone phosphate, Glyceraldehyde 3-phosphate (upregulated) and Fumarate (downregulated). Those metabolites co-occurred with certain bacterial taxa; Streptococcus, Veillonella, Actinomyces, Porphyromonas, Fusobacterium, and Granulicatella, regardless of the abundance of other taxa.These findings are crucial for understanding the etiology and dynamics of dental caries, and devising targeted interventions to prevent disease progression.© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

JTD Keywords: bacteria, biofilms, children, dental caries, generation, genomics, longitudinal model, metabolism, metabolomics, microscopy, non-invasive bioimaging, oral microbiome, plaque, restorations, signatures, Dental caries, Field-emission sem, Signatures

Drosophila is an amenable system for addressing the mechanics of morphogenesis. We describe a workflow for characterizing the mechanical properties of its ventral nerve cord (VNC), at different developmental stages, in live, flat dissected embryos employing atomic force microscopy (AFM). AFM is performed with spherical probes, and stiffness (Young's modulus) is calculated by fitting force curves with Hertz's contact model. For complete details on the use and execution of this protocol, please refer to Karkali et al. (2022).

JTD Keywords: atomic force microscopy (afm), developmental biology, model organisms, Animals, Atomic force microscopy, Atomic force microscopy (afm), Biology, Developmental biology, Drosophila, Elastic modulus, Microscopy, atomic force, Model organisms, Morphogenesis, Neurociencia, Neuroscience

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

Abstract Oxidative stress, which occurs when an organism is exposed to an adverse stimulus that results in a misbalance of antioxidant and pro-oxidants species, is the common denominator of diseases considered as a risk factor for SARS-CoV-2 lethality. Indeed, reactive oxygen species caused by oxidative stress have been related to many virus pathogenicity. In this work, simulations have been performed on the receptor binding domain of SARS-CoV-2 spike glycoprotein to study what residues are more susceptible to be attacked by ·OH, which is one of the most reactive radicals associated to oxidative stress. The results indicate that isoleucine (ILE) probably plays a crucial role in modification processes driven by radicals. Accordingly, QM/MM-MD simulations have been conducted to study both the ·OH-mediated hydrogen abstraction of ILE residues and the induced modification of the resulting ILE radical through hydroxylation or nitrosylation reactions. All in all, in silico studies show the importance of the chemical environment triggered by oxidative stress on the modifications of the virus, which is expected to help for foreseeing the identification or development of antioxidants as therapeutic drugs. Graphic abstract

JTD Keywords: atom abstraction, damage, density functionals, hydrogen abstraction, isoleucine, molecular dynamics, pathogenesis, protein, reactive oxygen species, receptor binding domain, residues, spike protein, Amino-acids, Hydrogen abstraction, Isoleucine, Molecular dynamics, Reactive oxygen species, Receptor binding domain, Spike protein

The quest for novel nanoscale materials for different applications necessitates that they are easy to obtain and have excellent physical properties and low toxicity. Moreover, considering the ongoing environmental impact of noxious chemical waste products, it is important to adopt eco-friendly approaches for nanoparticle synthesis. In this work, a natural polymer (medium molecular weight chitosan) derived from chitin was employed as a reducing agent to obtain gold nanoparticles (AuNPs) with a chitosan shell (AuNPs@CS) by a microwave oven. The chitosan is economically viable and cost-competitive in the market showing also nontoxic behavior in the environment and living organisms. The synthesized AuNPs@CS-FITC NPs were fully characterized by spectroscopic and microscopic characterization techniques. The size distribution of NPs was about 15 nm, which is a suitable dimension to use in biomedical applications due to their high tissue penetration, great circulation in blood, and optimal clearance as well as low toxicity. The prepared polymer-capped NPs were further functionalized with a fluorescent molecule, i.e., Fluorescein-5-isothiocyanate (FITC), to perform imaging in the cell. The results highlighted the goodness of the synthesis procedure, as well as the high internalization rate that resulted in an optimal fluorescence intensity. Thus, this work presents a good sustainable/green approach-mediated polymer nanocomposite for various applications in the field of diagnostic imaging.

JTD Keywords: Agent, Biomedical, Fluorescent, Gold nanoparticles, Green synthesis, Nanomaterials, Silver nanoparticles

Abstract Background Neural tissue has limited regenerative ability. To cope with that, in recent years a diverse set of novel tools has been used to tailor neurostimulation therapies and promote functional regeneration after axonal injuries. Method In this report, we explore cell-specific methods to modulate neuronal activity, including opto- and chemogenetics to assess the effect of specific neuronal stimulation in the promotion of axonal regeneration after injury. Results Opto- and chemogenetic stimulations of neuronal activity elicited increased in vitro neurite outgrowth in both sensory and cortical neurons, as well as in vivo regeneration in the sciatic nerve, but not after spinal cord injury. Mechanistically, inhibitory substrates such as chondroitin sulfate proteoglycans block the activity induced increase in axonal growth. Conclusions We found that genetic modulations of neuronal activity on both dorsal root ganglia and corticospinal motor neurons increase their axonal growth capacity but only on permissive environments.

JTD Keywords: activation, chemogenetics, electrical-stimulation, expression, functional recovery, increases, injury, motor cortex, neuronal activity, optogenetics, permissive substrate, promotes recovery, regeneration, Optogenetics, Regeneration, Spinal-cord

Tissue engineering is nowadays a powerful tool to restore damaged tissues and recover their normal functionality. Advantages over other current methods are well established, although a continuous evolution is still necessary to improve the final performance and the range of applications. Trends are nowadays focused on the development of multifunctional scaffolds with hierarchical structures and the capability to render a sustained delivery of bioactive molecules under an appropriate stimulus. Nanocomposites incorporating hydroxyapatite nanoparticles (HAp NPs) have a predominant role in bone tissue regeneration due to their high capacity to enhance osteoinduction, osteoconduction, and osteointegration, as well as their encapsulation efficiency and protection capability of bioactive agents. Selection of appropriated polymeric matrices is fundamental and consequently great efforts have been invested to increase the range of properties of available materials through copolymerization, blending, or combining structures constituted by different materials. Scaffolds can be obtained from different processes that differ in characteristics, such as texture or porosity. Probably, electrospinning has the greater relevance, since the obtained nanofiber membranes have a great similarity with the extracellular matrix and, in addition, they can easily incorporate functional and bioactive compounds. Coaxial and emulsion electrospinning processes appear ideal to generate complex systems able to incorporate highly different agents. The present review is mainly focused on the recent works performed with Hap-loaded scaffolds having at least one structural layer composed of core/shell nanofibers.

JTD Keywords: bone tissue, coaxial electrospinning, composite nanofibers, drug-release behavior, emulsion electrospinning, hydroxyapatite, in-vitro evaluation, mechanical-properties, osteogenic differentiation, pickering emulsions, protein adsorption, structured scaffolds, surface-initiated polymerization, tissue regeneration, Bone tissue, Coaxial electrospinning, Emulsion electrospinning, Hydroxyapatite, Multifunctional scaffolds, Poly(3-hydroxybutyrate) phb patches, Tissue regeneration

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

The ability to engineer complex multicellular systems has enormous potential to inform our understanding of biological processes and disease and alter the drug development process. Engineering living systems to emulate natural processes or to incorporate new functions relies on a detailed understanding of the biochemical, mechanical, and other cues between cells and between cells and their environment that result in the coordinated action of multicellular systems. On April 3-6, 2022, experts in the field met at the Keystone symposium "Engineering Multicellular Living Systems" to discuss recent advances in understanding how cells cooperate within a multicellular system, as well as recent efforts to engineer systems like organ-on-a-chip models, biological robots, and organoids. Given the similarities and common themes, this meeting was held in conjunction with the symposium "Organoids as Tools for Fundamental Discovery and Translation".

JTD Keywords: computational, engineered living, engineered organs, multicellular, Brain organoids, Cell diversity, Computational, Dynamics, Engineered living, Engineered organs, Heart, Maturation, Model, Multicellular, Mycobacterium-tuberculosis, Quantitative-analysis, Systems, Tissue deformation

Around 30-40% of patients with colorectal cancer (CRC) undergoing curative resection of the primary tumour will develop metastases in the subsequent years1. Therapies to prevent disease relapse remain an unmet medical need. Here we uncover the identity and features of the residual tumour cells responsible for CRC relapse. An analysis of single-cell transcriptomes of samples from patients with CRC revealed that the majority of genes associated with a poor prognosis are expressed by a unique tumour cell population that we named high-relapse cells (HRCs). We established a human-like mouse model of microsatellite-stable CRC that undergoes metastatic relapse after surgical resection of the primary tumour. Residual HRCs occult in mouse livers after primary CRC surgery gave rise to multiple cell types over time, including LGR5+ stem-like tumour cells2-4, and caused overt metastatic disease. Using Emp1 (encoding epithelial membrane protein 1) as a marker gene for HRCs, we tracked and selectively eliminated this cell population. Genetic ablation of EMP1high cells prevented metastatic recurrence and mice remained disease-free after surgery. We also found that HRC-rich micrometastases were infiltrated with T cells, yet became progressively immune-excluded during outgrowth. Treatment with neoadjuvant immunotherapy eliminated residual metastatic cells and prevented mice from relapsing after surgery. Together, our findings reveal the cell-state dynamics of residual disease in CRC and anticipate that therapies targeting HRCs may help to avoid metastatic relapse.© 2022. The Author(s), under exclusive licence to Springer Nature Limited.

JTD Keywords: colonization, defines, human colon, mutations, plasticity, retrieval, stem-cells, subtypes, underlie, Animal, Animal cell, Animal experiment, Animal model, Animal tissue, Animals, Article, Cancer, Cancer growth, Cancer immunotherapy, Cancer inhibition, Cancer recurrence, Cancer staging, Cell, Cell adhesion, Cell migration, Cell population, Cell surface receptor, Cohort analysis, Colorectal cancer, Colorectal neoplasms, Colorectal tumor, Comprehensive molecular characterization, Controlled study, Crispr-cas9 system, Cytoskeleton, Disease exacerbation, Disease progression, Dynamics, Emp1 gene, Epithelial membrane protein-1, Extracellular matrix, Flow cytometry, Fluorescence intensity, Gene expression, Genetics, Human, Human cell, Humans, Immune response, Immunofluorescence, In situ hybridization, Marker gene, Metastasis potential, Mice, Minimal residual disease, Mouse, Neoplasm proteins, Neoplasm recurrence, local, Neoplasm, residual, Nonhuman, Pathology, Phenotype, Prevention and control, Protein, Receptors, cell surface, Single cell rna seq, Tumor, Tumor protein, Tumor recurrence

Mesenchymal condensation is a prevalent morphogenetic transition that is essential in chondrogenesis. However, the current understanding of condensation mechanisms is limited. In vivo, progenitor cells directionally migrate from the surrounding loose mesenchyme towards regions of increasing matrix adherence (the condensation centers), which is accompanied by the upregulation of fibronectin. Here, we focused on the mechanisms of cell migration during mesenchymal cell condensation and the effects of matrix adherence. Dendrimer-based nanopatterns of the cell-adhesive peptide arginine-glycine-aspartic acid (RGD), which is present in fibronectin, were used to regulate substrate adhesion. We recorded collective and single-cell migration of mesenchymal stem cells, under chondrogenic induction, using live-cell imaging. Our results show that the cell migration mode of single cells depends on substrate adhesiveness, and that cell directionality controls cell condensation and the fusion of condensates. Inhibition experiments revealed that cell???cell interactions mediated by N-cadherin (also known as CDH2) are also pivotal for directional migration of cell condensates by maintaining cell???cell cohesion, thus suggesting a fine interplay between cell???matrix and cell???cell adhesions. Our results shed light on the role of cell interactions with a fibronectin-depositing matrix during chondrogenesis in vitro, with possible applications in regenerative medicine.

JTD Keywords: Alpha-v-beta-3, Arginine-glycine-aspartic acid, Cell migration, Chondrogenesis, Dynamics, Expression, Fibronectin, Gastrulation, Involvement, Mechanisms, Mesenchymal condensation, Model, N-cadherin, Nanopatterned substrates, Rgd

Calcium phosphate cements (CPCs) are attractive synthetic bone grafts as they possess osteoconductive and osteoinductive properties. Their biomimetic synthesis grants them an intrinsic nano-and microporosity that resembles natural bone and is paramount for biological processes such as protein adhesion, which can later enhance cell adhesion. However, a main limitation of CPCs is the lack of macroporosity, which is crucial to allow cell colonization throughout the scaffold. Moreover, CPCs lack specific motifs to guide cell interactions through their membrane proteins. In this study, we explore a strategy targeting simultaneously both macroporosity and cell binding motifs within CPCs by the use of recombinant silk. A silk protein functionalized with the cell binding motif RGD serves as foaming template of CPCs to achieve biomimetic hydroxyapatite (HA) scaffolds with multiscale porosity. The synergies of RGD-motifs in the silk macroporous template and the biomimetic features of HA are explored for their potential to enhance mesenchymal stem cell adhesion, proliferation, migration and differentiation. Macroporous Silk-HA scaffolds improve initial cell adhesion compared to a macroporous HA in the absence of silk, and importantly, the presence of silk greatly enhances cell migration into the scaffold. Additionally, cell proliferation and osteogenic differentiation are achieved in the scaffolds.

JTD Keywords: Bioceramics, Bone, Bone regeneration, Composites, Degradation, Fabrication, Hydroxyapatite, Hydroxyapatite scaffolds, Injectability, Porosity, Recombinant spider silk, Rgd motifs, Silk, Stem-cells

Gradients of signaling pathways within the intestinal stem cell (ISC) niche are instrumental for cellular compartmentalization and tissue function, yet how are they sensed by the epithelium is still not fully understood. Here a new in vitro model of the small intestine based on primary epithelial cells (i), apically accessible (ii), with native tissue mechanical properties and controlled mesh size (iii), 3D villus-like architecture (iv), and precisely controlled biomolecular gradients of the ISC niche (v) is presented. Biochemical gradients are formed through hydrogel-based scaffolds by free diffusion from a source to a sink chamber. To confirm the establishment of spatiotemporally controlled gradients, light-sheet fluorescence microscopy and in-silico modeling are employed. The ISC niche biochemical gradients coming from the stroma and applied along the villus axis lead to the in vivo-like compartmentalization of the proliferative and differentiated cells, while changing the composition and concentration of the biochemical factors affects the cellular organization along the villus axis. This novel 3D in vitro intestinal model derived from organoids recapitulates both the villus-like architecture and the gradients of ISC biochemical factors, thus opening the possibility to study in vitro the nature of such gradients and the resulting cellular response.© 2022 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.

JTD Keywords: 3d architectures, biomolecular gradients, colon, crypt, engineering organoids, hydrogels, identification, in silico modeling, intestinal stem cell niches, light sheet fluorescence microscopy, niche, permeability, photolithography, regeneration, villus, wnt, 3d architectures, Biomolecular gradients, Engineering organoids, In silico modeling, Intestinal stem cell niches, Light sheet fluorescence microscopy, Photolithography, Stem-cell

One of humanity's greatest challenges is space exploration, which requires an in-depth analysis of the data continuously collected as a necessary input to fill technological gaps and move forward in several research sectors. Focusing on space crew healthcare, a critical issue to be addressed is tissue regeneration in extreme conditions. In general, it represents one of the hottest and most compelling goals of the scientific community and the development of suitable therapeutic strategies for the space environment is an urgent need for the safe planning of future long-term manned space missions. Osteopenia is a commonly diagnosed disease in astronauts due to the physiological adaptation to altered gravity conditions. In order to find specific solutions to bone damage in a reduced gravity environment, bone tissue engineering is gaining a growing interest. With the aim to critically investigate this topic, the here presented review reports and discusses bone tissue engineering scenarios in microgravity, from scaffolding to bioreactors. The literature analysis allowed to underline several key points, such as the need for (i) biomimetic composite scaffolds to better mimic the natural microarchitecture of bone tissue, (ii) uniform simulated microgravity levels for standardized experimental protocols to expose biological materials to the same testing conditions, and (iii) improved access to real microgravity for scientific research projects, supported by the so-called democratization of space.© 2022. The Author(s).

JTD Keywords: biomaterials, collagen/hydroxyapatite, composite scaffolds, in-vitro, mineralization, proliferation, regenerative medicine, stem-cells, vivo, Hydroxyapatite scaffolds

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

Antibody-functionalized nanoparticles (NPs) have shown numerous benefits in drug delivery and biosensing, improving the specificity of cell targeting and analyte detection, respectively. However, one of the main challenges is the lack of control over antibody orientation on the NP surface. Popular and easy conjugation strategies, such as carbodiimide-based conjugations, lead to a random orientation of antibodies on the NPs, compromising ligand functionality and contributing to undesired biological effects and reduced target recognition. While new methods for more controlled NP functionalization have been proposed, there is a lack of techniques that can elucidate the orientation of the antibodies at the single-particle level to determine the conjugation outcome and, therefore, the NPs' potential in selective targeting. Here, spectrally-resolved direct stochastic optical reconstruction microscopy (SR-dSTORM), an optical super-resolution technique, is introduced to quantify the relationship between total and functional NP conjugated cetuximab antibodies at the single-particle level. An evident single-particle heterogeneity in total and functional cetuximab is observed, leading to particles with different functional : total ratios. Additionally, the results indicate that the functional : total ratio of cetuximab highly depends on the conjugated cetuximab concentration. Overall, SR-dSTORM represents a direct approach for the NP structure-functionality relationship quantification, providing a platform to improve antibody-conjugated NPs characterization and facilitating their rational design.

JTD Keywords: Heterogeneity, Superresolution microscopy

Blood-vessel formation generates unique vascular patterns in each individual. The principles governing the apparent stochasticity of this process remain to be elucidated. Using mathematical methods, we find that the transition between two fundamental vascular morphogenetic programs-sprouting angiogenesis and vascular remodeling-is established by a shift of collective front-to-rear polarity of endothelial cells in the mouse retina. We demonstrate that the competition between biochemical (VEGFA) and mechanical (blood-flow-induced shear stress) cues controls this collective polarity shift. Shear stress increases tension at focal adhesions overriding VEGFA-driven collective polarization, which relies on tension at adherens junctions. We propose that vascular morphogenetic cues compete to regulate individual cell polarity and migration through tension shifts that translates into tissue-level emergent behaviors, ultimately leading to uniquely organized vascular patterns.Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.

JTD Keywords: activation, angiogenesis, dynamics, flow, forces, image, mechanisms, vinculin, Angiogenesis, Cell polarity, Fluid shear, Mechanobiology, Morphogenesis, Shear stress

Upon the initiation of collective cell migration, the cells at the free edge are specified as leader cells; however, the mechanism underlying the leader cell specification remains elusive. Here, we show that lamellipodial extension after the release from mechanical confinement causes sustained extracellular signal-regulated kinase (ERK) activation and underlies the leader cell specification. Live-imaging of Madin-Darby canine kidney (MDCK) cells and mouse epidermis through the use of Förster resonance energy transfer (FRET)-based biosensors showed that leader cells exhibit sustained ERK activation in a hepatocyte growth factor (HGF)-dependent manner. Meanwhile, follower cells exhibit oscillatory ERK activation waves in an epidermal growth factor (EGF) signaling-dependent manner. Lamellipodial extension at the free edge increases the cellular sensitivity to HGF. The HGF-dependent ERK activation, in turn, promotes lamellipodial extension, thereby forming a positive feedback loop between cell extension and ERK activation and specifying the cells at the free edge as the leader cells. Our findings show that the integration of physical and biochemical cues underlies the leader cell specification during collective cell migration.Copyright © 2022 Elsevier Inc. All rights reserved.

JTD Keywords: activation, c-met, contact inhibition, focal adhesions, heparan-sulfate, mechanical forces, morphogenesis, rho, stress fibers, Collective cell migration, Erk, Feedback regulation, Fret, Growth-factor receptor, Hgf, Lamellipodia, Leader cell specification, Signal transduction, Traction force, Wound healing

JTD Keywords: biochemical engineering, neurotrauma and neurodegenerative disease, optogenetics and dreadds, spinal cord injury (sci), Biochemical engineering, Neurotrauma and neurodegenerative disease, Optogenetics and dreadds, Sensorimotor, Spinal cord injury (sci)

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

Great advances in cancer treatment have been undertaken in the last years as a consequence of the development of new antitumoral drugs able to target cancer cells with decreasing side effects and a better understanding of the behavior of neoplastic cells during invasion and metastasis. Specifically, drug delivery systems (DDS) based on the use of hydroxyapatite nanoparticles (HAp NPs) are gaining attention and merit a comprehensive review focused on their potential applications. These are derived from the intrinsic properties of HAp (e.g., biocompatibility and biodegradability), together with the easy functionalization and easy control of porosity, crystallinity and morphology of HAp NPs. The capacity to tailor the properties of DLS based on HAp NPs has well-recognized advantages for the control of both drug loading and release. Furthermore, the functionalization of NPs allows a targeted uptake in tumoral cells while their rapid elimination by the reticuloendothelial system (RES) can be avoided. Advances in HAp NPs involve not only their use as drug nanocarriers but also their employment as nanosystems for magnetic hyperthermia therapy, gene delivery systems, adjuvants for cancer immunotherapy and nanoparticles for cell imaging.

JTD Keywords: antitumoral, cancer, cell imaging, controlled-release, drug-carrier, efficient drug-delivery, fatty-acid-metabolism, fe3o4 nanoparticles, gene delivery, hydroxyapatite, hyperthermia, immunotherapy, in-vitro, magnetic hydroxyapatite, nano-hydroxyapatite, protein adsorption, tumor-growth, Calcium-phosphate nanoparticles, Cancer, Immunotherapy

Abstract Bioengineered human skeletal muscle tissues have emerged in the last years as new in vitro systems for disease modeling. These bioartificial muscles are classically fabricated by encapsulating human myogenic precursor cells in a hydrogel scaffold that resembles the extracellular matrix. However, most of these hydrogels are derived from xenogenic sources, and the culture media is supplemented with animal serum, which could interfere in drug testing assays. On the contrary, xeno-free biomaterials and culture conditions in tissue engineering offer increased relevance for developing human disease models. In this work, we used human platelet lysate-based nanocomposite hydrogels (HUgel) as scaffolds for human skeletal muscle tissue engineering. These hydrogels consist of human platelet lysate reinforced with cellulose nanocrystals (a-CNC) that allow tunable mechanical, structural, and biochemical properties for the 3D culture of stem cells. Here, we developed hydrogel casting platforms to encapsulate human muscle satellite stem cells in HUgel. The a-CNC content was modulated to enhance matrix remodeling, uniaxial tension, and self-organization of the cells, resulting in the formation of highly aligned, long myotubes expressing sarcomeric proteins. Moreover, the bioengineered human muscles were subjected to electrical stimulation, and the exerted contractile forces were measured in a non-invasive manner. Overall, our results demonstrated that the bioengineered human skeletal muscles could be built in xeno-free cell culture platforms to assess tissue functionality, which is promising for drug development applications.

JTD Keywords: 3d culture, generation, identification, image, manipulate, matrigel, mechanics, model, platelet lysate, scaffolds, skeletal muscle, tissue engineering, xeno-free, 3d culture, Animals, Extracellular matrix, Humans, Hydrogels, Muscle development, Muscle, skeletal, Platelet lysate, Platform, Skeletal muscle, Tissue engineering, Tissue scaffolds, Xeno-free

Cell-material interactions are regulated by mimicking bone extracellular matrix on the surface of biomaterials. In this regard, reproducing the extracellular conditions that promote integrin and growth factor (GF) signaling is a major goal to trigger bone regeneration. Thus, the use of synthetic osteogenic domains derived from bone morphogenetic protein 2 (BMP-2) is gaining increasing attention, as this strategy is devoid of the clinical risks associated with this molecule. In this work, the wrist and knuckle epitopes of BMP-2 are screened to identify peptides with potential osteogenic properties. The most active sequences (the DWIVA motif and its cyclic version) are combined with the cell adhesive RGD peptide (linear and cyclic variants), to produce tailor-made biomimetic peptides presenting the bioactive cues in a chemically and geometrically defined manner. Such multifunctional peptides are next used to functionalize titanium surfaces. Biological characterization with mesenchymal stem cells demonstrates the ability of the biointerfaces to synergistically enhance cell adhesion and osteogenic differentiation. Furthermore, in vivo studies in rat calvarial defects prove the capacity of the biomimetic coatings to improve new bone formation and reduce fibrous tissue thickness. These results highlight the potential of mimicking integrin-GF signaling with synthetic peptides, without the need for exogenous GFs.© 2022 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.

JTD Keywords: adhesion formation, bmp-2, cell adhesions, in-vivo, integrin, mesenchymal stem-cells, morphogenetic protein-2, multifunctionality, osteoblastic differentiation, osteogenic differentiation, rgd-dwiva, rgd-peptides, titanium biofunctionalization, titanium surfaces, Animals, Biocompatible materials, Biomimetic peptides, Bone morphogenetic protein 2, Bone regeneration, Cell adhesions, Cell differentiation, Epitopes, Extracellular matrix, Integrins, Marrow stromal cells, Multifunctionality, Osteogenesis, Osteogenic differentiation, Peptides, Rats, Rgd-dwiva, Titanium, Titanium biofunctionalization

Most of the conventional in vitro models to test biomaterial-driven vascularization are too simplistic to recapitulate the complex interactions taking place in the actual cell microenvironment, which results in a poor prediction of the in vivo performance of the material. However, during the last decade, cell culture models based on microfluidic technology have allowed attaining unprecedented levels of tissue biomimicry. In this work, we propose a microfluidic-based 3D model to evaluate the effect of bioactive biomaterials capable of releasing signalling cues (such as ions or proteins) in the recruitment of endogenous endothelial progenitor cells, a key step in the vascularization process. The usability of the platform is demonstrated using experimentally-validated finite element models and migration and proliferation studies with rat endothelial progenitor cells (rEPCs) and bone marrow-derived rat mesenchymal stromal cells (BM-rMSCs). As a proof of concept of biomaterial evaluation, the response of rEPCs to an electrospun composite made of polylactic acid with calcium phosphates nanoparticles (PLA+CaP) was compared in a co-culture microenvironment with BM-rMSC to a regular PLA control. Our results show a significantly higher rEPCs migration and the upregulation of several pro-inflammatory and proangiogenic proteins in the case of the PLA+CaP. The effects of osteopontin (OPN) on the rEPCs migratory response were also studied using this platform, suggesting its important role in mediating their recruitment to a calcium-rich microenvironment. This new tool could be applied to screen the capacity of a variety of bioactive scaffolds to induce vascularization and accelerate the preclinical testing of biomaterials. STATEMENT OF SIGNIFICANCE: : For many years researchers have used neovascularization models to evaluate bioactive biomaterials both in vitro, with low predictive results due to their poor biomimicry and minimal control over cell cues such as spatiotemporal biomolecule signaling, and in vivo models, presenting drawbacks such as being highly costly, time-consuming, poor human extrapolation, and ethically controversial. We describe a compact microphysiological platform designed for the evaluation of proangiogenesis in biomaterials through the quantification of the level of sprouting in a mimicked endothelium able to react to gradients of biomaterial-released signals in a fibrin-based extracellular matrix. This model is a useful tool to perform preclinical trustworthy studies in tissue regeneration and to better understand the different elements involved in the complex process of vascularization.Copyright © 2022. Published by Elsevier Ltd.

JTD Keywords: angiogenesis, bioactive materials, bone regeneration, bone-formation, calcium-phosphate, extracellular calcium, in-vitro, interstitial flow, ion release, microfluidic model, signalling gradient, substitutes, tissue engineering, vascularization, vegf, Ion release, Mesenchymal stem-cells, Tissue engineering, Vascularization

Growing evidence suggests that the physical properties of the cellular microenvironment influence cell migration. However, it is not currently understood how active physical remodelling by cells affects migration dynamics. Here we report that cell clusters seeded on deformable collagen-I networks display persistent collective migration despite not showing any apparent intrinsic polarity. Clusters generate transient gradients in collagen density and alignment due to viscoelastic relaxation of the collagen networks. Combining theory and experiments, we show that crosslinking collagen networks or reducing cell cluster size results in reduced network deformation, shorter viscoelastic relaxation time and smaller gradients, leading to lower migration persistence. Traction force and Brillouin microscopy reveal asymmetries in force distributions and collagen stiffness during migration, providing evidence of mechanical cross-talk between cells and their substrate during migration. This physical model provides a mechanism for self-generated directional migration on viscoelastic substrates in the absence of internal biochemical polarity cues.; Cell clusters mechanically reorganize viscoelastic collagen networks, resulting in transient gradients in collagen density, alignment and stiffness that promote spontaneous persistent migration.

JTD Keywords: Cell-migration, Design, Invasion, Limits, Mechanics, Microscopy, Morphogenesis, Motility, Rear, Rigidity

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

Nanosized artificial antigen-presenting cells (aAPCs), synthetic immune cell mimics that aim to activate T cells ex or in vivo, offer an effective alternative to cellular immunotherapies. However, comprehensive studies that delineate the effect of nano-aAPC topology, including nanoparticle morphology and ligand density, are lacking. Here, we systematically studied the topological effects of polymersome-based aAPCs on T cell activation. We employed an aAPC library created from biodegradable poly(ethylene glycol)-block-poly(d,l-lactide) (PEG-PDLLA) polymersomes with spherical or tubular shape and variable sizes, which were functionalized with αCD3 and αCD28 antibodies at controlled densities. Our results indicate that high ligand density leads to enhancement in T cell activation, which can be further augmented by employing polymersomes with larger size. At low ligand density, the effect of both polymersome shape and size was more pronounced, showing that large elongated polymersomes better activate T cells compared to their spherical or smaller counterparts. This study demonstrates the capacity of polymersomes as aAPCs and highlights the role of topology for their rational design.

JTD Keywords: antibody density, artificial antigen-presenting cells, biodegradable polymersomes, design, expansion, immunotherapy, nano-immunotherapy, nanoparticle morphology, t cell activation, Biodegradable polymersomes, Nanoparticle morphology, Synthetic dendritic cells

Cells are constantly exposed to various chemical and physical stimuli. While much has been learned about the biochemical factors that regulate secretory trafficking from the endoplasmic reticulum (ER), much less is known about whether and how this trafficking is subject to regulation by mechanical signals. Here, we show that subjecting cells to mechanical strain both induces the formation of ER exit sites (ERES) and accelerates ER-to-Golgi trafficking. We found that cells with impaired ERES function were less capable of expanding their surface area when placed under mechanical stress and were more prone to develop plasma membrane defects when subjected to stretching. Thus, coupling of ERES function to mechanotransduction appears to confer resistance of cells to mechanical stress. Furthermore, we show that the coupling of mechanotransduction to ERES formation was mediated via a previously unappreciated ER-localized pool of the small GTPase Rac1. Mechanistically, we show that Rac1 interacts with the small GTPase Sar1 to drive budding of COPII carriers and stimulates ER-to-Golgi transport. This interaction therefore represents an unprecedented link between mechanical strain and export from the ER.© 2022 The Authors. Published under the terms of the CC BY 4.0 license.

JTD Keywords: cells, copii, docking, endoplasmic reticulum, endoplasmic-reticulum, er, gtpase, mechanobiology, proliferation, protein, reticulum exit sites, web server, Copii, Fast interaction refinement, Mechanobiology

Increased liver glycogen content has been shown to reduce food intake, attenuate obesity, and improve glucose tolerance in a mouse model of high-fat diet (HFD)-induced obesity. Here we studied the contribution of liver glycogen to the regulation of obesity and glucose metabolism in a model of type 2 diabetes and obesity, namely the db/db mouse. To this end, we crossed db/db mice with animals overexpressing protein targeting to glycogen (PTG) in the liver to generate db/db mice with increased liver glycogen content (db/db-PTG). Hepatic PTG overexpression reduced food intake and fat weight and attenuated obesity and hyperglycemia in db/db mice. Db/db-PTG mice showed similar energy expenditure and physical activity to db/db mice. PTG overexpression reduced liver phosphoenolpyruvate carboxykinase (PEPCK) protein levels and repressed hepatic glucose production in db/db mice. Moreover, increased liver glycogen elevated hepatic ATP content in these animals. However, lipid metabolism was not modified by PTG overexpression. In conclusion, increased liver glycogen content ameliorates the diabetic and obesity phenotype in db/db mice.Copyright © 2022 López-Soldado, Guinovart and Duran.

JTD Keywords: atp, db, dyslipidemia, food intake, glucose, homeostasis, liver, metabolism, mouse, receptor, Atp, Db/db, Food intake, Food-intake, Glucose, Glycogen, Liver

Understanding the dopaminergic system is a priority in neurobiology and neuropharmacology. Dopamine receptors are involved in the modulation of fundamental physiological functions, and dysregulation of dopaminergic transmission is associated with major neurological disorders. However, the available tools to dissect the endogenous dopaminergic circuits have limited specificity, reversibility, resolution, or require genetic manipulation. Here, we introduce azodopa, a novel photoswitchable ligand that enables reversible spatiotemporal control of dopaminergic transmission. We demonstrate that azodopa activates D1-like receptors in vitro in a light-dependent manner. Moreover, it enables reversibly photocontrolling zebrafish motility on a timescale of seconds and allows separating the retinal component of dopaminergic neurotransmission. Azodopa increases the overall neural activity in the cortex of anesthetized mice and displays illumination-dependent activity in individual cells. Azodopa is the first photoswitchable dopamine agonist with demonstrated efficacy in wild-type animals and opens the way to remotely controlling dopaminergic neurotransmission for fundamental and therapeutic purposes.

JTD Keywords: azobenzene, behavior, brainwave, d-1, dopamine, gpcr, in vivo electrophysiology, inhibitors, optogenetics, optopharmacology, photochromism, photopharmacology, photoswitch, stimulation, zebrafish, Animals, Animals, wild, Azobenzene, Behavior, Brainwave, Dopamine, Gpcr, In vivo electrophysiology, Ligands, Mice, Optogenetics, Optopharmacology, Photochromism, Photopharmacology, Photoswitch, Receptors, Synaptic transmission, Zebrafish

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

Acute Respiratory Distress Syndrome is one of the more common fatal complications in COVID-19, characterized by a highly aberrant inflammatory response. Pre-clinical models to study the effect of cell therapy and anti-inflammatory treatments have not comprehensively reproduced the disease due to its high complexity. This work presents a novel physiomimetic in vitro model for Acute Respiratory Distress Syndrome using lung extracellular matrix-derived hydrogels and organ-on-a-chip devices. Monolayres of primary alveolar epithelial cells were cultured on top of decellullarized lung hydrogels containing primary lung mesenchymal stromal cells. Then, cyclic stretch was applied to mimic breathing, and an inflammatory response was induced by using a bacteriotoxin hit. Having simulated the inflamed breathing lung environment, we assessed the effect of an anti-inflammatory drug (i.e., dexamethasone) by studying the secretion of the most relevant inflammatory cytokines. To better identify key players in our model, the impact of the individual factors (cyclic stretch, decellularized lung hydrogel scaffold, and the presence of mesenchymal stromal cells) was studied separately. Results showed that developed model presented a more reduced inflammatory response than traditional models, which is in line with what is expected from the response commonly observed in patients. Further, from the individual analysis of the different stimuli, it was observed that the use of extracellular matrix hydrogels obtained from decellularized lungs had the most significant impact on the change of the inflammatory response. The developed model then opens the door for further in vitro studies with a better-adjusted response to the inflammatory hit and more robust results in the test of different drugs or cell therapy.

JTD Keywords: alveolar epithelial cells, ards, extracellular matrix, hydrogels, inflammation, lung-on-a-chip, Acute lung injury, Alveolar epithelial cells, Ards, Dexamethasone, Epithelial-mesenchymal transition, Extracellular matrix, Extracellular-matrix, Hydrogels, Inflammation, Lung-on-a-chip, Mesenchymal stromal cells, Oxygen, Stem-cells

Liver fibrosis staging is a key element driving the prognosis of patients with chronic liver disease. Currently, biopsy is the only technique capable of diagnosing liver fibrosis in patients with alcohol-related liver disease (ArLD) and non-alcoholic fatty liver disease (NAFLD) unequivocally. Non-invasive (e.g. plasma-based) biomarker assays are attractive tools to diagnose and stage disease, yet must prove that they are reliable and sensitive to be used clinically. Here we demonstrate 1 H nuclear magnetic resonance as a method to rapidly quantify the endogenous concentration of ammonium ions from human plasma extracts and show their ability to report upon early and advanced stages of ArLD and NAFLD. We show that, irrespective of the disease aetiology, ammonium concentration is a more robust and informative marker of fibrosis stage than current clinically assessed blood hepatic biomarkers. Subject to validation in larger cohorts, the study indicates that the method can provide accurate and rapid staging of ArLD and NAFLD without need for an invasive biopsy.This article is protected by copyright. All rights reserved.

JTD Keywords: ammonium quantification, blood biomarkers, chronic liver disease, disease biomarkers, hepatic dysfunction, nmr, pathogenesis, Ammonium quantification, Hepatic dysfunction, Hepatic-encephalopathy

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

The neocortex of P301S mice, used as a model of fronto-temporal lobar degeneration linked to tau mutation (FTLD-tau), and wild-type mice, both aged 9 months, were analyzed with conventional label-free phosphoproteomics and SWATH-MS (sequential window acquisition of all theoretical fragment ion spectra mass spectrometry) to assess the (phospho)proteomes. The total number of identified dysregulated phosphoproteins was 328 corresponding to 524 phosphorylation sites. The majority of dysregulated phosphoproteins, most of them hyperphosphorylated, were proteins of the membranes, synapses, membrane trafficking, membrane vesicles linked to endo- and exocytosis, cytoplasmic vesicles, and cytoskeleton. Another group was composed of kinases. In contrast, proteins linked to DNA, RNA metabolism, RNA splicing, and protein synthesis were hypophosphorylated. Other pathways modulating energy metabolism, cell signaling, Golgi apparatus, carbohydrates, and lipids are also targets of dysregulated protein phosphorylation in P301S mice. The present results, together with accompanying immunohistochemical and Western-blotting studies, show widespread abnormal phosphorylation of proteins, in addition to protein tau, in P301S mice. These observations point to dysregulated protein phosphorylation as a relevant contributory pathogenic component of tauopathies.

JTD Keywords: (phospho)proteomics, cytoskeleton, kinases, membranes, tau, (phospho)proteomics, Animals, Cytoskeleton, Disease models, animal, Frontotemporal lobar degeneration, Kinases, Membranes, Mice, Mice, transgenic, Networks, Oxidative stress, Pathology, Phosphoproteins, Phosphoproteome analysis, Phosphorylation, Tau, Tau proteins, Tauopathies, Tauopathy

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