3D in vitro model systems, such as hydrogels, have garnered popularity due to their ability to more accurately recapitulate in vivo environments compared to 2D cell culture systems. However, methods which involve casting hydrogels by hand may be time consuming, have poor reproducibility, and reduced capacity to generate complex structures. Hence, 3D bioprinting has emerged as a useful tool for the high throughput production of in vitro tissue models such as hydrogels and complex constructs. Here, we demonstrate the mechanical properties, printability, and ability to support single cells and spheroids in culture for two highly characterised composite bioinks: Alginate/Gelatin (AlgGel), which is ionically crosslinked, and Alginate/Gelatin Methacrylate (GelMA) (AlgGelMA), whereby the GelMA is crosslinked by illumination with UV light. In this study, we engineered gels that exhibit a wide range of stiffnesses, which vary due to the concentration of crosslinking polymer present. AlgGel hydrogels were softer (1.5-4.5 kPa), and stiffness decreased with time in culture, however, AlgGelMA hydrogels were stiffer (6-40 kPa), and the stiffness increased with time. Microarchitectural studies using Scanning Electron Microscopy and Microcomputed Tomography (mu CT) revealed that hydrogels produced using both bioinks bore a highly porous structure, further simulating in vivo conditions. To assess the ability of both bioink families to support cell culture, the Acute Myeloid Leukaemia cell line THP-1 and human Mesenchymal Stem Cells (hMSCs) as single cells and spheroids were bioprinted in each bioink. Interestingly, THP-1 cells formed larger clusters when cultured within AlgGel bioinks compared to AlgGelMA. Additionally, hMSCs appeared to be unable to migrate through the AlgGel matrix, as single hMSCs displayed rounded morphologies and hMSC spheroid shape was not disrupted after seven days. Contrastingly, hMSCs and spheroids cultured within AlgGelMA hydrogels were able to invade the gel matrix and migrate. Together, these data demonstrate that both AlgGel and AlgGelMA bioinks show promise for use as the basis of 3D bioprinted in vitro tissue models.

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In this study, a nasal spray was formulated and tested co-loading grape seed extract, thymol, and camphor in penetration enhancer containing vesicles (PEVs) tailored to synergistically protect the nasal mucosa against oxidative stress and bacterial colonization. Based on their previously demonstrated effects, PEVs were prepared with propylene glycol (PG) and further enriched with carrageenan to promote muco-adhesion. The mean diameter of PG-PEVs was similar to 177 nm, and that of carrageenan PG-PEVs was similar to 194 nm. The polydispersity index ranged from 0.25 to 0.27, confirming the homogeneity of the dispersions. The zeta potential was significantly negative (similar to- 63 mV) and the entrapment efficiency was similar to 88 %, irrespective of vesicle composition. Sprayability studies disclosed that both PG-PEVs and carrageenan-PG-PEVs generated droplets larger than 10 mu m, thus appropriate for the deposition in the nasal cavity. Regional nasal deposition studies, carried out with a realistic nasal replica, highlighted that formulation droplets were deposited in the vestibule and turbinate areas of the nose. The ability of formulations to inhibit protein denaturation confirmed their anti-inflammatory effects. In vitro study with A549 and CuFi-1 cells, underlined that PG-PEVs and especially carrageenan PG-PEVs were nontoxic (viability similar to 140 %) and effectively counteracted cell apoptosis caused by hydrogen peroxide, restoring healthy conditions. The in vivo study in mice demonstrated that grape seed extract, thymol, and camphor-loaded carrageenan PG-PEVs were highly effective in counteracting the proliferation of Staphylococcus aureus.

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Acute respiratory distress syndrome often necessitates prolonged periods of mechanical ventilation for patient management. Therefore, it is crucial to make appropriate decisions regarding extubation to prevent potential harm to patients and avoid the associated risks of reintubation and extubation cycles. One atypical form of acute respiratory distress syndrome is associated with COVID-19, impacting patients admitted to the intensive care unit. This study presents the design of two classifiers: the first employs machine learning techniques, while the second utilizes a convolutional neural network. Their purpose is to assess whether a patient can safely be disconnected from a mechanical ventilator following a spontaneous breathing test. The machine learning algorithm uses descriptors derived from the variability of time-frequency representations computed with the non-uniform fast Fourier transform. These representations are applied to time series data, which consist of markers extracted from the electrocardiographic and respiratory flow signals sourced from the Weandb database. The input image for the convolutional neural network is formed by combining the spectrum of the RR signal and the spectrum of two parameters recorded from the respiratory flow signal, calculated using non-uniform fast Fourier transform. Three pre-trained network architectures are analyzed: Googlenet, Alexnet and Resnet-18. The best model is obtained with a CNN with the Resnet-18 architecture, presenting an accuracy of 90.1 +/- 4.3%.

JTD Keywords: Convolutional neural networ, Extubation, Instantaneous frequency, Mechanical ventilation, Mechanically ventilated patients, Non-uniform fast fourier transform, Variabilit, Weaning

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.

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Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and Long Covid-19 (LC-19) are complex conditions with no diagnostic markers or consensus on disease progression. Despite extensive research, no in vitro model exists to study skeletal muscle wasting, peripheral weakness, or potential therapies. We developed 3D in vitro skeletal muscle tissues to map muscle adaptations to patient sera over time. Short exposures (48 H) to patient sera led to a significant reduction in muscle contractile strength. Transcriptomic analysis revealed the upregulation of protein translation, glycolytic enzymes, disturbances in calcium homeostasis, hypertrophy, and mitochondrial hyperfusion. Structural analyses confirmed myotube hypertrophy and elevated mitochondrial oxygen consumption In ME/CFS. While muscles initially adapted by increasing glycolysis, prolonged exposure (96-144 H) caused muscle fragility and weakness, with mitochondria fragmenting into a toroidal conformation. We propose that skeletal muscle tissue in ME/CFS and LC-19 progresses through a hypermetabolic state, leading to severe muscular and mitochondrial deterioration. This is the first study to suggest such transient metabolic adaptation.

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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

Over the past 30 years, polyacrylamide (PAAm) hydrogels have become essential tools to mimic the mechanical properties, chemical composition, and dimensionality of the extracellular matrix (ECM) in in vitro mechanobiology studies. This brief review highlights recent developments that have transformed PAAm hydrogels from simple 2D static elastic hydrogels to complex ECM-mimicking systems involving protein micropatterning, mechanical patterning, stretching, DNA tension probes, viscoelasticity, and the microfabrication of 3D systems. We focus on novel mechanobiological questions that have been elucidated using these platforms and give a perspective on the future of PAAm hydrogels for mechanobiology research.

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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.

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A flexible molecule can adjust its shape to diffuse through a pore having a diameter smaller than its average dimension. The fluctuations of molecular dimensions as well as the rotations of the molecule inside the pores require special attention to the definition of the molecular size descriptors for diffusive transport in the pores. Within the framework of the previously proposed theory of the steric free energy barrier, we suggest an effective spherical model of a molecule of an arbitrary shape and define two size descriptors-the effective average radius of the molecule and its variance. The two geometric parameters effectively encode both the fluctuations of the molecule and its rotation in the pore. Once determined for a molecule, they can be used to estimate the steric free energy in a pore of arbitrary radius. The results can be applied to diffusive transport through biological nanopores as well as to size-exclusion molecular filtering. (c) 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(https://creativecommons.org/licenses/by/4.0/).https://doi.org/10.1063/5.0284331

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In recent years, enzyme-powered nanomotors (NMs) have emerged as promising tools for biomedical applications. They exhibit active motion in complex media, whereas traditional passive nanoparticles (NPs) typically remain trapped. Despite their potential, nanogels (NGs)-3D, cross-linked polymeric networks with high water retention and environmental responsiveness-remain underexplored as cores for enzymatic NMs. Here, fine-tuned NGs designed to confer smart properties are presented, allowing them to adapt their size and density in response to external stimuli (e.g., pH, temperature, and redox conditions). After anchoring urease to these NGs to produce nanogel-nanomotors (NGs-NMs), they exhibited both individual and collective motion at a very low urea concentration, enabling displacement in highly viscous environments. To achieve this, four NGs formulations based on p-(N-isopropylacrylamide) co-polymerized with p-Itaconic acid (p-(NIPAM-co-IAc)) are developed, cross-linked with either N,N '-methylenebisacrylamide (BIS) and/or N,N '-bis(acryloyl)cystamine (BAC), and coated with p-(2-hydroxyethyl methacrylate) (p-HEMA). This results, obtained via confocal microscopy and flow cytometry, demonstrate their rapid cell internalization. Moreover, synchrotron-based infrared spectroscopy (SR-FTIRM) allowed to demonstrate that NGs-NMs can tune the physicochemical composition of tumoral cells. This findings underscore the potential of NGs-NMs, combining adaptability, safety, and efficacy. They represent the evolution in NMs technology, paving the way for groundbreaking advancements in personalized medicine.

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Atomic force microscopy (AFM) is widely used to measure surface topography of solid, soft, and living matter at the nanoscale. Moreover, by mapping forces as a function of distance to the surface, AFM can provide a wealth of information beyond topography, with nanomechanical properties as a prime example. Here, a method based on photothermal off-resonance tapping (PORT) is presented to increase the speed of such force spectroscopy measurements by at least an order of magnitude, thereby enabling high-throughput, quantitative nanomechanical mapping of a wide range of materials. Specifically, photothermal actuation is used to modulate the position of the AFM probe at frequencies that far exceed those possible with traditional actuation by piezo-driven z scanners. Understanding and accounting for the microscale thermal and mechanical behavior of the AFM probe, the study determines the resulting probe position at sufficient accuracy to allow rapid and quantitative nanomechanical examination of polymeric and metallic materials.

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Despite significant efforts in developing novel biomaterials to regenerate tissue, only a few of them have successfully reached clinical use. It has become clear that the next generation of biomaterials must be multifunctional. Smart biomaterials can respond to environmental or external stimuli, interact in a spatial-temporal manner, and trigger specific tissue/organism responses. In this study, how to fabricate the fabrication of novel 3D-printed and bioresorbable scaffolds, with embedded crystals that can convert near-infrared (NIR) light into visible light, is presented. It is demonstrated that these biophotonic scaffolds are not only bioactive and bioresorbable, but can also be promising as a platform for the controlled release or activation of photoactivated drugs locally and on demand, under illumination. The scaffolds are analyzed based on their up-conversion spectroscopic properties and their chemical stability in simulated body fluid. Furthermore, it is demonstrated that the up-conversion properties of the scaffolds are sufficient to release the signaling molecule nitric oxide (NO) and to photoisomerize the muscarinic ligand Phthalimide-Azo-Iperoxo (PAI), in a controlled manner, upon NIR light stimulus. Finally, to assess their biocompatibility for potential implantation, a preliminary study is conducted with human adipose stem cells cultured in contact with scaffolds. Live/dead assays, morphological analysis, CyQUANT analysis, and ion release measurements confirm that, despite some release of the upconverter crystals, the dissolution of the biophotonic materia and its dissolution by-products, are biocompatible. These findings highlight the potential of these bioresorbable biophotonic scaffolds for localized drug release in response to NIR light stimuli.

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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.

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Nucleic acid hybridization in bimolecular and folding reactions is a fundamental kinetic process susceptible to water solvation, counterions, and chemical modifications with intricate enthalpy-entropy compensation effects. Such effects hinder the typically weak temperature dependencies of enthalpies and entropies quantified by the heat capacity change upon duplex formation. Using a temperature-jump optical trap, we investigate the folding thermodynamics and kinetics of DNA hairpins of varying stem sequences and loop sizes in the temperature range of 5-40 circle C. From a kinetic analysis and using a Clausius-Clapeyron equation in force, we derive the hybridization heat capacity changes Delta Cp per GC and AT bp, finding 36 +/- 3 and 29 +/- 3 cal/(mol K), respectively. The almost equal values imply similar degrees of freedom arrest upon GC and AT bp formation during duplex formation. Folding kinetics on DNA hairpins of varying loop sizes show that the transition states (TS) in duplex formation have high free energies but low Delta Cp values relative to the native state. Consequently, TS have low configurational entropy in agreement with the funnel-like energy landscape hypotheses. Our study underlines the validity of general principles in the hybridization and folding of nucleic acids determined by the TS's Delta Cp values.

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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.

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Peptide-based supramolecular nanostructures offer a versatile platform with substantial promise for clinical translation in regenerative medicine. These systems allow for the incorporation of biologically active sequences and can be engineered to modulate tissue-specific parameters such as stiffness, diffusivity, and biodegradability. We developed here a bioactive supramolecular nanostructure containing a peptide designed based on glial cell-derived neurotrophic factor. These nanostructures form scaffolds that mimic important trophic effects provided by this growth factor on iPSC-derived human dopaminergic neurons. Our in vitro data show that the nanostructures promote cell viability, confer neuroprotection against 6-hydroxydopamine toxicity, enhance neuronal morphology, facilitate electrophysiological maturation, and induce genes involved in neuronal survival. We also found that the scaffold promoted axonal extension in midbrain human organoids. These findings suggest that the supramolecular system could be useful to improve outcomes in cell-based therapies for Parkinson's disease, where progressive dopaminergic degeneration is a hallmark.

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Biological sex significantly influences the prevalence, incidence, and severity of numerous human diseases, yet it remains an underappreciated variable in biomedical research. While 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 weeks) and late (12 weeks) 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.

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Masclans Enviz, Joan Ramon

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The efficient degradation of organic pollutants is critical for environmental sustainability, driving the search for eco-friendly catalytic materials. Biopolymer-based magnetic hydrogels are promising candidates, though current systems often face challenges such as poor mechanical stability, uneven nanocatalyst distribution, and complex synthesis. Here, we present a green, simple, and scalable method for fabricating chitosan-agarose dual-network hydrogels incorporating Fe3O4 nanoparticles (NPs) synthesized in situ from two iron salts. This strategy ensures uniform NPs dispersion within a mechanically robust and biocompatible matrix, enabling multifunctional hydrogels that combine catalytic efficiency, magnetic responsiveness, and reusability. The Fe3O4 content was systematically varied to tune the hydrogel's physicochemical, mechanical, and magnetic properties. Structural characterization by X-ray diffraction and transmission electron microscopy confirmed successful in situ Fe3O4 NPs formation, with differences in size and morphology depending on the iron precursor. Rheological analysis showed increased stiffness with higher Fe3O4 content, while swelling tests revealed reduced water uptake due to pore filling. Catalytic performance was evaluated using model pollutants achieving up to 94 % degradation within 90 min under mild conditions. These nanocomposite hydrogels offer a sustainable, magnetically recoverable, and reusable platform for efficient pollutant removal, highlighting the synergistic advantages of dualbiopolymer matrices and in situ nanocatalyst formation for water remediation.

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Unjamming transitions from a solid-like to a fluid-like state are a gateway to breast epithelial cancer invasion. However, the mechanical interplay between phase transitions and dimension transitions, in particular wetting, remains elusive, despite being critical for understanding the onset of metastatic dissemination. This study shows that unjamming, mediated by the RAB5A GTPase, alters carcinoma spheroid fluidity, rigidity, and rewires adhesion mechanics to drive supracellular active wetting as a new mode of tumor expansion. Spheroid fluidification enhances the selective expression of integrin subunits and increases focal adhesion dynamics, inducing a fluid-like spreading behavior on specific matrix ligands. Notably, nanoscale regulation of integrin clustering can select for distinct phase transitions at the collective scale upon wetting. In this framework, fluidized spheroids polarize into cohesive "supracells", and maintain a stiff peripheral actin bundle as measured by nanomechanical mapping. Furthermore, a combination of Brillouin microscopy and 2.5D traction force analysis reveals a mechanical switch within the spheroid core, characterized by significant cell softening and a reduction in compressive forces exerted on the substrate, thereby mimicking the wetting of a liquid droplet. These findings establish unjamming-driven active wetting as a key mechanism to comprehend the molecular and biophysical underpinnings of solid tumor invasion.

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The movement of cells and microorganisms in response to chemical gradients, chemotaxis, is fundamental to the evolution of myriad biological processes. In this work, we demonstrate that even the simplest cell-like structures are capable of chemotactic navigation. By encapsulating enzymes within lipid vesicles that incorporate a minimal number of membrane pores, we reveal that a solitary vesicle can actively propel itself toward an enzyme substrate gradient. Specifically, vesicles loaded with either glucose oxidase or urease and embedded with corresponding transmembrane proteins were tracked within a microfluidic device under a controlled substrate gradient. Our findings establish that a system comprising only an encapsulated enzyme and a single transmembrane pore is sufficient to initiate chemotaxis. This proof-of-concept model underscores the minimalistic yet powerful nature of cellular navigation mechanisms, providing a previously unknown perspective on the origins and evolution of chemotactic behavior in biological systems.

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We employed dielectric spectroscopy to analyze charge conduction, glass transition temperature, and relaxation dynamics in six alginate (Alg) samples at low temperature. All underwent vitrification of a hydrated amorphous fraction: the as-stored Na-Alg powder at 220 K, the temperature-quenched Ca-Alg hydrogel and xerogel at 212 K, the frozen Na-Alg solution and the Na-Alg exposed to water-vapor saturated atmosphere at 194 K, and the slowly cooled hydrogel at 170 K. All samples displayed a Johari-Goldstein relaxation, and three of them displayed a structural relaxation; both processes originated from coupled Alg-H2O motions in the hydrated amorphous fraction. Charge conduction in all samples was dominated by Grotthuss proton shuttling (either in bulk water/ice or in hydration layers). H2O-rich samples displayed the H-bond network relaxation of ice, with an activation energy between 25 and 31 kJ mol-1, close to the energy of formation of one H-bond per H2O molecule. This relaxation was faster in the quenched hydrogel than in the slowly crystallized hydrogel and the frozen solution, likely due to a smaller average size of ice domains in the former; the latter samples display two separate ice relaxations, likely due to ionic impurities in the ice domains in contact with the Alg chains. The Na-Alg powder equilibrated in a water-vapor saturated atmosphere also displayed the local relaxation of bulk-like amorphous water with an activation energy of 51 kJ mol-1, equivalent to two H-bonds per H2O molecule. Most samples displayed spectral changes between 260 and 270 K due to ice melting. In the fast-quenched hydrogel, a premelting transition was observed at 220 K.

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Biohybrid actuators leveraging living muscle tissue offer the potential to replicate natural motion for biomedical and robotic applications. However, challenges such as limited force output and inefficient force transfer at tissue interfaces persist. The myotendinous junction, a specialized interface connecting muscle to the tendon, plays a critical role in efficient force transmission for movement. Engineering muscle-tendon units in vitro is essential for replicating native musculoskeletal functions in biohybrid actuators. Here, we present a three-dimensionally bioprinted system integrating skeletal muscle tissue with tendon-mimicking anchors containing fibroblasts, forming a biomimetic interdigitated myotendinous junction. Using computational models, we optimized muscle geometries to enhance deformation and force generation. The engineered system improved mechanical stability, myofiber maturation, and force transmission, generating contractile forces of up to 350 micronewtons over a 3-month period. This work highlights how biomimetic designs and mechanical optimization can advance bioactuator technologies for applications in medicine and robotics.

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The field of nanophotonics has seen remarkable advances, with gold-based materials standing out. By precisely fine-tuning the size and shape of metal nanoparticles (NPs), such as gold nanoparticles (AuNPs), it has been possible to gain control over light interaction, modulating localized surface plasmon resonance (LSPR), a phenomenon that involves the collective oscillation of free conduction electrons. This has opened the path toward more powerful biomedical applications, including surface-enhanced Raman spectroscopy (SERS) and photothermal therapy (PTT). When AuNPs dimensions fall below 2 nm, they become gold nanoclusters (AuNCs), losing the LSPR but acquitting fluorescence due to their molecule-like behavior. This unique feature makes them ideal for high-resolution imaging, biomarker detection, and advanced therapies. Beyond traditional uses, the recent inclusion of AuNPs into nanomotors (NMs) enhances precise in vivo tracking and targeted drug delivery. This review highlights the different applications of plasmonic nanomaterials with particular emphasis on AuNPs and AuNCs as a function of their shapes, sizes, and stabilization ligands. Moreover, it dives into the biosensing applications of plasmonic materials by addressing their so-called far-field and near-field optical properties, giving a detailed overview of different high-sensitivity immunoassays and biosensing. A comprehensive outlook on the evolution of plasmonic-based materials for the next therapies is provided.

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Isothermal microcalorimetry (IMC) is a promising tool for diagnosing periprosthetic joint infection (PJI), based on real-time measurement of growth-related heat production of pathogens, and faster than conventional microbial cultures. However, the feasibility of identifying specific pathogens in clinical samples using IMC has yet to be proven. This study implements machine learning and transfer learning convolutional neural network (CNN) models to detect and identify pathogens causing PJI, using IMC data alone. IMC data were obtained from synovial fluid samples, including 174 aseptic samples and 239 PJI samples containing five different bacterial strains. XGBoost, multi-layer perceptron, support vector machine, random forest, and three transfer learning CNN models were implemented to detect PJI and identify five bacterial strains in PJI samples. The binary XGBoost classifier yielded a 100% accuracy in PJI detection, whereas the multiclass XGBoost classifier and the combined transfer learning CNN classifier reached an overall accuracy of 90.3% and 91.5%, respectively, in PJI identification, with biological significance of extracted features in the XGBoost model facilitating its interpretability and usage in clinical practice. The strain with the lowest recall (83.3%) was PA, whereas SE was the strain with the lowest precision (78.9%). The results demonstrate the feasibility of automatic detection and identification of pathogens causing PJI using their IMC growth patterns and machine learning models. This adds a critical missing feature to IMC, contributing to accelerating the diagnosis of PJI and the selection of antibiotic therapy.

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Random lasers (RLs) represent a distinctive class of laser systems wherein emission arises from multiple scattering events occurring with random orientations within a disorder media. Departing from conventional laser architectures, RL emission is primarily governed by random scattering phenomena, inherently limiting precise control over emission directionality and threshold intensity. Achieving a laser system with finely controllable RL characteristics poses a significant challenge. In this investigation, using polymeric high internal phase emulsion (PolyHIPE) scaffolds, known for their highly customizable surface topographies, is exploredas scattering media platforms for RLs. Dye on the PolyHIPE surface enables interaction with external stimuli, showing sensing potential. Using surface chemical modification techniques, the amphiphilic molecular is grafted onto the HIPE surface and RL behavior is investigated across HIPEs with controllable pore sizes. Notably, a discernible correlation emerges between the RL threshold and the collective influence of polyHIPE platform morphology and gain particle configuration. This heightened adaptability and finely tunable precision in the RL system offer increased versatility, enabling the tailored design of optimal lasers suited for diverse application scenarios. Consequently, these advancements substantially enhance the utility and versatility of RLs in various fields.

JTD Keywords: Block copolymers, Mar, Polyhipes, Polymeric high internal phase emulsion (polyhipe), Porous materials, Random lase

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.

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When exposed to the oral environment, dental implants, like natural surfaces, become substrates for microbial adhesion and accumulation, often leading to implant-related infections-one of the main causes of implant failure. These failures impose significant costs on patients, clinicians, and healthcare systems. Despite extensive research, there is no consensus on the most effective protocol for managing peri-implantitis. Biomedical engineering has aimed to address this challenge by developing biocompatible implants with surface properties designed to enhance biological responses and reduce polymicrobial accumulation. Due to the complexity of interactions between implants and biological systems, no single material property can drive these processes. Instead, a combination of physical, chemical, and mechanical properties is required to ensure a safe and effective response. Antimicrobial coatings are developed either by incorporating antimicrobial agents onto surfaces or modifying the material's physicochemical properties. These coatings utilize a range of compounds for contact-killing or as drug-delivery systems. While biomaterials science has advanced rapidly in enhancing implant surfaces, these bioengineering techniques have progressed more rapidly than our understanding of the pathogenesis of implant infections. To bridge this gap, biomedical engineering must address emerging knowledge about implant infections, focusing on controlling microbial accumulation while simultaneously managing inflammatory responses to support tissue healing. This review critically evaluates current evidence on implant infection pathogenesis, antimicrobial coating technologies, and systematically assesses their in vivo (animal and human evidence) efficacy to guide future advancements in implant infection mitigation.

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Izquierdo, Luis

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Soft and flexible robotics is an emerging field that attracts a huge interest due to its ability to produce bioinspired devices that are easily adaptable to the environment. Biohybrid Machines (BHM) represent a category of soft robots that integrate biological tissues, such as engineered muscle tissues, as actuating systems. Although these devices present several advantages in some applications, their proper actuation still represents a challenge for researchers. This paper focuses on the development of a portable and programmable electrical stimulator designed to control muscle fiber-based biohybrid actuators. The stimulator, made using off-the-shelf components, was designed as a stacking of three independent printed circuit boards (PCBs), connected vertically in order to result in a final device with compact dimensions of 59 mm 28 mm 25 mm. The stimulation circuit is capable of delivering currents up to 18 mA with a voltage compliance of ± 90 V, and a power consumption of approximately 1.3 W. The device’s ability to induce twitch and tetanic contractions in a biohybrid actuator is demonstrated in different stimulation conditions. A practical application was also explored through a test case involving a flexible catheter prototype controlled by a biohybrid actuator, demonstrating its potential utility in a BHMs.

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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

Insulation materials are essential for engineering efficiency, as they directly reduce energy losses or eliminate the need for extra components to compensate for them. However, most insulation materials are non-biodegradable polymers that significantly contribute to environmental degradation during production and disposal. This study explores the use of bioinspired chito-cellulosic materials -a family of biological composites known in structural applications for their low cost, versatile manufacturing, and ecological integration- as sustainable insulation. The study compares three chito-cellulosic variants with different cellulose compositions and evaluates their electrical, thermal, and acoustic insulation capabilities, as well as flammability, biodegradability, environmental impact, and mechanical properties. The insulating results are compared to conventional polyurethane foams, demonstrating lower thermal insulation capabilities, similar electrical insulation, and better acoustic insulation. Moreover, they offer the advantages of being 3D-printable, fully biodegradable in environmental conditions, and fireproof, highlighting their potential as a viable green alternative to synthetic insulators.

JTD Keywords: Cellulose, Chitosan, Flam, Foam, Insulation

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.

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Kidney stones are some of the most common urinary diseases, affecting 12% of the population. The high prevalence and recurrence of this disease urges the development of more targeted and effective treatment with lower side effects and less invasiveness avoiding recurrence and prolonged drug administration. Particularly for recurring stone formers, the current methods of persistent drug treatment and repetitive surgeries for stone removal are unsatisfying solutions that bring a huge burden to the patients and healthcare systems. For these reasons, a delivery strategy that provides drug administration at the disease site through active, wireless transport is urgently needed to improve urinary tract disease treatment. A wireless treatment of kidney stones is proposed with the help of flexible, magnetically steered, enzymatically active robots. These robots are designed to navigate in the urinary tract and locally dissolve the stones by action of embedded urease. The robots are made of millimeter-sized, gelatin-based polymer strips with embedded micromagnets and encapsulated urease which constantly converts urea to increase urinary pH. This study demonstrates enhanced stone dissolution and the robots' magnetic navigation through the different parts of a 3D printed human urinary tract model. A clinical ultrasound system allows real-time localization of the robots. This research proposes a less invasive and more targeted strategy for medical interventions in the urinary tract with potential to circumvent surgery in case of uric acid kidney stones, which is relevant especially in the light of high prevalence and recurrence of kidney stones.

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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.

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Study question: Can we classify human oocytes non-invasively using METAPHOR based on their metabolic hyperspectral (HS) signature and mitochondrial content? Summary answer: METAPHOR provides a tool to determine the physiology of human oocytes non-invasively based on their metabolism and live observation of mitochondrial content and activity.

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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.

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Bacterial colonization on biomaterials is a major issue, leading to approximately 20% of implant failures due to infection and biofilm formation. To address this, peptide-based hydrogels incorporating tailored bioactive peptides have emerged as promising candidates for applications in tissue engineering and infection control. Here, we have designed peptide sequences that incorporate i) a self-assembling unit (SaU) and ii) bioactive motifs, including the well-known arginine-glycine-aspartate (RGD) sequence to promote cell adhesion or an antimicrobial peptide derived from lactoferrin (LF) to exhibit antibacterial properties. To aid in the gelation, these peptides were combined with hyaluronic acid (HA), rendering peptide-based hydrogels without the need for additional external assembly triggers, simplifying their application in biomedical contexts. This protocol allowed for a spontaneous formation of a 3D fibrillar network, with structural and physicochemical properties suitable for tissue engineering. The biological evaluation revealed the ability of RGD-based hydrogels to increase the adhesion and spreading of osteoblastic cells compared to controls, while the LF-based hydrogels significantly reduced the viability and attachment of both Gram-positive and Gram-negative strains, clearly affecting bacterial morphology. This report demonstrates the feasibility of this technology to produce hydrogels incorporating distinct biological cues, highlighting their potential as versatile biomaterials to address diverse biomedical challenges.

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3D printing has emerged as a transformative technology in several manufacturing processes, being of particular interest in biomedical research for allowing the creation of 3D structures that mimic native tissues. The process of tissue 3D printing entails the construction of functional, 3D tissue structures. In this article, the integration of ferrofluid consisting of iron oxide nanoparticles into muscle cell-laden bioink is presented to obtain a 3D printed magnetically responsive muscle tissue, i.e., the ferromuscle. Using extrusion-based methods, the seamless integration of biocompatible ferrofluids are achieved to cell-laden hydrogels. The resulting ferromuscle tissue exhibits improved tissue differentiation demonstrated by the increased force output upon electrical stimulation compared to muscle tissue prepared without ferrofluid. Moreover, the magnetic component originating from the iron oxide nanoparticles allows magnetic guidance, as well as good cytocompatibility and biodegradability in cell culture. These findings offer a new versatile fabrication approach to integrate magnetic components into living constructs, with potential applications as bioactuators and for future integration in smart, functional muscle implants.

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Aparicio, Conrado

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Efficient drug delivery across the blood–brain barrier (BBB) remains a significant obstacle in treating central nervous system (CNS) disorders. This review provides an in-depth analysis of the structural and molecular mechanisms underlying BBB integrity and its functional properties. We detail the role of key cellular and molecular components that regulate selective molecular transport across the barrier, alongside a description of the current therapeutic approaches for brain drug delivery, including those leveraging receptor-mediated transcytosis. Emphasis is placed on multivalency-based strategies that enhance the specificity of nanoparticle targeting and improve transport efficacy across the BBB. Additionally, we discuss the added value of integrating mathematical and computational models with experimental validation for accelerating BBB-targeted delivery systems optimisation.

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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.

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Living organisms, from single cells to multicellular systems, are capable of moving as a response to local stimuli using swarming intelligence, a trait researchers aim to replicate in artificial systems. Common strategies observed in natural swarms include motility towards specific signals from the environment, communication among individual units, coordination and cooperation to achieve complex tasks. Inspired by these features, the focus in bioinspired motile nanosystems has shifted from studying individual units to exploring and controlling collective behaviours. Various propulsion mechanisms including magnetic, electric or acoustic fields, as well as onboard chemical reactions, have enabled artificial micromotor and nanomotor (MNM) swarms that can move collectively as a response to environmental inputs. The controlled navigation and improved tissue penetration of MNM swarms is promising within the biomedical field, including in the active transport of medical agents. Despite these exciting advances, artificial MNMs still fall short of the complexity and autonomy seen in biological systems. This Perspective explores the collective behaviour of biological swarms and bioinspired artificial self-propelled nanosystems. We discuss how swarming intelligence applied to synthetic active nanosystems enables swarms to perform various tasks. Finally, we discuss challenges, including material limitations, information storage, communication between swarms and prospects for intelligent swarming systems.

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Seeger-Nukpezah, Tamina

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Catalytically active hydroxyapatite (ca-HAp) decorated with zirconia nanoparticles (ZrO2 NPs) is presented as a nanocomposite catalyst (ca-HAp/ZrO2) capable of performing highly efficient nitrogen to ammonia (N2-to-NH3) fixation reactions under mild conditions. Accordingly, reactions were carried out in a batch reactor operating at 120 degrees C, 6 bar of N2, and 20 mL of water, under UV irradiation (14 W) for 72 h. The yield of NH3 obtained was 1.592 +/- 0.146 mmolgc -1, which represents a N2 fixation efficiency of 6.4%. Near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) studies under in situ conditions (i.e., at elevated pressure and temperature and during UV irradiation) and density functional theory simulations (DFT) allowed us to elucidate the catalytic mechanism of the system. The ca-HAp/ZrO2 nanocomposites exhibit a strong synergy arising from the initial photoactivation of N2 by means of the pi-backdonation mechanism in ZrO2 (N2 is anchored by four Zr4+ atoms) followed by the dinitrogen spillover toward the Ca(I)2+ binding sites. Such sites, preferentially exposed in the (001) crystallographic planes of ca-HAp, show high activity due to the enhanced electron transfer properties of ca-HAp. These catalytic nanocomposites represent a viable alternative to the conventional catalysts used for N2-to-NH3 fixation reactions.

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Amyloid aggregates are pathological hallmarks of many human diseases, but how soluble proteins nucleate to form amyloids is poorly understood. Here, we use combinatorial mutagenesis, a kinetic selection assay, and machine learning to massively perturb the energetics of the nucleation reaction of amyloid-β (Aβ42), the protein that aggregates in Alzheimer’s disease. In total, we measure the nucleation rates of >140,000 variants of Aβ42 to accurately quantify the changes in free energy of activation of the reaction for all possible amino acid substitutions in a protein and, in addition, to quantify >600 energetic interactions between mutations. Strong energetic couplings suggest that the Aβ42 nucleation reaction transition state is structured in a short C-terminal region, providing a structural model for the reaction that may initiate Alzheimer’s disease. Using this approach it should be possible to reveal the energetic structures of additional amyloid transition states and, in combination with additional selection assays, protein transition states more generally.

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Gradients are widespread in nature, including within the human body, making the study of nanomotors' collective dynamics in gradients crucial to advancing biomedical applications and deepening the understanding of natural active matters. However, the comprehensive understanding of nanomotors' collective dynamics under gradients remains underexplored, particularly. This study employs urease-based nanomotors (UrNMs) as a model system to explore their collective dynamics within a urea gradient, revealing three fundamental principles that govern their behavior: density-driven convection, UrNMs' response to the urea gradient, and a coupling effect between UrNMs and their environment. Initially, migration is dominated by convection-induced motion arising from the steep gradient. As convection gradually diminishes, UrNMs' positive response to the urea gradient becomes the dominant factor governing their migration. Notably, the coupling effect between nanomotors and the gel, plays a crucial role in the migration process. This coupling effect arises from hydrogen bonding between product anions and the gel, which generates ionic gradients. The dominant influence of electric force is validated by pH-controlled experiments. These insights advance the fundamental understanding of gradient-responsive nanomotor behavior and offer inspiration for the design of intelligent, environment-sensitive active systems.

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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.

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Skin is a barrier that protects us against physical, chemical and biological agents. However, any damage to the skin can disrupt this barrier and therefore compromise its function leading to sometimes catastrophic consequences like sepsis. Thus, methods to detect early signs of infection are necessary. In this work, we have developed a straightforward method for producing 2D nanomembranes with regularly spaced 1D metallic nanostructures integrating sensing capabilities to pH and NADH (nicotinamide adenine dinucleotide), which are critical analytes revealing infection. To achieve this, we have successfully fabricated a bilayered nanomembrane combining a pH-responsive polyaniline (PANI) layer and a nanoperforated poly(lactic acid) (PLA) layer containing gold nanowires (Au NWs) as NADH sensing element. SEM, FTIR, Raman and AFM techniques revealed the formation of the bilayered PANI/PLA nanomembrane and the successful incorporation of the Au NWs inside the nanoperforations. The resulting bilayered nanomembrane showed significant flexibility and conformability onto different substrates due to the softness of the polymers and the ultrathin thickness with stiffness values similar to human skin. These nanomembranes also exhibited remarkable electrochemical sensing performance towards pH and NADH detection. Thus, the nanomembrane displayed linearity with good sensitivity (47 mVpH-1) in the critical pH range 4-10 and fast response time (10 s). On the other hand, PANI/PLA-Au nanomembranes also allowed the quantitative sensing of NADH with a limit of detection of 0.39 mM and a sensitivity of 1 mu A cm-2 mM-1 in the concentration range 0-5 mM.

JTD Keywords: Bilayered nanomembranes, Biomimetic membranes, Free-standing films, Gold nanowires, Nad, Nanoparticles, Pani, Ph and nadh sensor, Pla, Polyaniline

Amyloid fibrils, which are aggregates of misfolded proteins characterized by 13-sheet-rich structures, are implicated in several neurodegenerative and systemic pathologies, including Alzheimer's and Parkinson's diseases and type II diabetes mellitus. Traditional amyloid markers, such as Congo Red and Thioflavin T, are widely used for amyloid detection but present limitations, particularly in cellular assays, due to spectral interference and aggregation inhibition. This study investigates YAT2150, a novel fluorescent dye with enhanced amyloid-binding specificity and sensitivity, as a potential alternative to conventional dyes. We evaluated YAT2150's efficacy for detecting amyloid aggregates in both in vitro and in cellula assays. First, we compared its fluorescence intensity and binding specificity to that of Thioflavin Tin amyloid fibril assays, demonstrating that YAT2150 exhibits high affinity and selectivity for amyloid structures, with minimal interference from non-aggregated proteins. Furthermore, we explored YAT2150's utility in Escherichia colt as a model system for studying protein aggregation and amyloid formation in a procaryotic cellular context. Our findings indicate that YAT2150 effectively labels amyloid-like inclusion bodies in E. colt producing a robust fluorescence signal with low background noise. These results suggest that YAT2150 is a promising new tool for amyloid research, offering greater sensitivity compared to traditional dyes, even in complex cellular environments.

JTD Keywords: Aggregation, Amyloid, Amyloid inhibitor, Bacterial inclusion-bodies, Detect, In-vitro, Inclusion bodies, Kinetics, Model, Parameters, Prion, Screening, Silico, Yat2150

Antifouling coatings are vital to enhance the performance of medical devices, aiming to mitigate bodily reactions by shielding their surface. Despite significant advancements in antifouling coatings, like those based on zwitterionic monomers and hydroxyl-functionalized (meth)acrylamides, limitations like decreased antifouling properties after functionalization and complement system activation hinder their application in blood. Here, a novel class of ultrathin surface-attached hydrogels is presented, consisting of hydrophilic non-charged green solvent-based monomers and preventing protein adsorption while offering on-demand degradability. Unlike the best antifouling brushes, the coatings are easily applicable, unaffected by charges, and free of complement system-activating groups. The hydrogels are formed using copolymers of N,N-dimethyl lactamide acrylate (DMLA) and benzophenone acrylate (BPA). Moreover, 5,6-benzo-2-methylene-1,3-dioxepane (BMDO) is incorporated to introduce hydrolyzable ester. The coating of state-of-the-art devices is demonstrated with X-ray photoelectron spectroscopy (XPS), analyze surface energy components, and confirm their antifouling properties with surface plasmon resonance (SPR). The coatings are non-cytotoxic toward MRC-5 fibroblasts, exhibit repellency against methicillin-resistant Staphylococcus aureus (MRSA), and effectively prevent thrombus formation on devices in blood. This work establishes a versatile platform for next-generation coatings in medical and industrial applications, matching the antifouling efficiency of the most advanced solutions and offering regeneration of substrates by erasing the coating.

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Skeletal muscle tissue represents an attractive powering component for biohybrid robots, as traditional actuators used in the soft robotic context often rely on complex mechanisms and lack scalability at small dimensions. This article proposes a monolithic biohybrid flexure mechanism actuated by a bioengineered skeletal muscle tissue. The design leverages the contractile properties of a bioengineered skeletal muscle to produce a bending motion in a monolithic, tubular mechanism made of a soft and biocompatible silicone blend. This structure integrates two cylindrical pillars that facilitate force transmission from the bioengineered muscle tissue. Performance assessments reveal excellent contractile and stable behavior upon electrical stimulation, compared to current biohybrid actuation systems, with enhanced performance as the mechanism's internal and external diameters decrease. Finite-element simulations further reveal distinct force-displacement responses in mechanisms with different flexural rigidity. This innovative, scalable, and easy-to-fabricate design represents a significant step forward in the development of novel biohybrid machines.

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The conversion of methane into useful chemicals has an enormous interest from both economic and social points of view as it is an important feedstock in chemical industry and is the second most important greenhouse gas contributor to climate change. In this work, we report the sustainable and selective conversion of methane into formic acid in batch and continuous-flow conditions using a biocatalyst made of permanently polarized. Formic acid was the only product identified in absence of UV irradiation, while a mixture of formic acid and methanol was obtained under UV light. The reaction pathway was investigated, on the one hand experimentally, by varying the reaction time, temperature and pressure in a batch reactor, in addition to the analysis of gaseous products, which allowed to understand the role of UV light in the change of selectivity, and on the other hand theoretically, using Density Functional Theory (DFT) computer calculations. The reaction pathway was experimentally investigated varying the reaction time, temperature and pressure in a batch reactor, besides gas products analysis, enabling to understand the UV light role in selectivity shift. Continuous-flow reactions using non-irradiated catalysts were conducted at 120 degrees C, produced a formic acid yield of 4.2 mmol per gram of catalyst and hour.

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PEGylation prevents aggregation and enhances the systemic circulation of nanoparticles (NPs), improving the delivery of actives to targeted cells. In this study, a conjugation reaction was used to attach polyethylene glycol (PEG) chains of molecular weights 750 and 5000 Da onto the surface of poly(lactic-co-glycolic acid) (PLGA) NPs obtained using the phase inversion composition methods, with carbodiimide/N-hydroxysuccinimide (NHS) and carbodiimide/sulfo-NHS activation reactions. Proton nuclear magnetic resonance indicated a higher degree of decoration (ca. 44.7 %) when carbodiimide/sulfo-NHS activation and PEG low molecular weight (750 Da) were used. Short incubation times (2 h at 37 °C) in the presence of 10 % fetal bovine serum showed no significant changes in particle size compared to pristine NPs. After 5 h of incubation, PEGylated NPs exhibited increase size (101.4 ± 15.3 nm) and polydispersity (0.6 ± 0.01). The presence of PEG chains decorating NPs reduced antioxidant release from NPs to ca. 10 % after 24 h at 37 °C following the Korsmeyer–Peppas model and governed by a Fickian diffusion mechanism. The antioxidant capacity of NPs showed a dose-activity relationship with ca. 60 % inhibition at 0.16 mg mL−1 NP concentration and an EC50 of 51.7 ± 3.3 μg mL−1. Cell culture studies indicated no cytotoxicity for PLGA and PEGylated NPs up to 0.05 mg mL−1. Internalization studies confirmed cellular uptake into SHSY5Y cells. The impact of PEGylated NPs on blood-brain barrier (BBB) permeabilization was evaluated in a BBB-on-chip model, showing that PLGA encapsulation and PEGylated NPs, though to a lesser extent, facilitated crossing and permeabilization through the endothelial layer, demonstrating their potential for effective brain delivery.

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Neurodegenerative diseases such as Alzheimer's disease and amyotrophic lateral sclerosis are characterized by progressive neuronal loss and the accumulation of misfolded proteins including amyloid proteins. Current therapeutic options include the use of antibodies for these proteins, but novel chemical strategies need to be developed. The disaccharide trehalose has been widely reported to prevent misfolding and aggregation of proteins, and we therefore investigated the conjugation of this moiety to biocompatible peptide amphiphiles (TPAs) known to undergo supramolecular polymerization. Using X-ray scattering, circular dichroism, and infrared spectroscopy, we found that trehalose conjugation destabilized the internal beta-sheet structures within the TPA supramolecular polymers as evidenced by a lower thermal transition. Thioflavin T fluorescence showed that these metastable TPA nanofibers suppressed A42 aggregation. Interestingly, we found that the suppression involved supramolecular copolymerization of TPA polymers with A beta 42, which effectively trapped the peptides within the filamentous structures. In vitro assays with human induced pluripotent stem cell-derived neurons demonstrated that these TPAs significantly improved neuron survival compared to other conditions. Our study highlights the potential of properly tuned supramolecular polymerizations of monomers to safely remove amyloidogenic proteins in neurodegeneration.

JTD Keywords: Aggregation, Beta, Disease, Model, Molecule, Motor-neurons, Nanoparticles, Nanostructures, Promote, Trehalose

The proteome of Plasmodium falciparum exhibits a marked propensity for aggregation. This characteristic results from the parasite's AT-rich genome, which encodes numerous proteins with long asparagine-rich stretches and low structural complexity, which lead to abundant intrinsically disordered regions. While this poses challenges for the parasite, the propensity for protein aggregation may also serve functional roles, such as stress adaptation, and could therefore be exploited by targeting it as a potential vulnerable spot in the pathogen. Here, we overexpressed an aggregation-prone segment of the P. falciparum ubiquitin transferase (PfUTf), an E3 ubiquitin ligase protein that has been previously demonstrated to regulate the stability of parasite proteins involved in invasion, development and drug metabolism. Overexpression of PfUTf in P. falciparum had evident phenotypic effects observed by transmission electron microscopy and confocal fluorescence microscopy, increased endogenous protein aggregation, disrupted proteostasis, and caused significant growth impairment in the parasite. Combined with dihydroartemisinin treatment, PfUTf overexpression had a synergistic effect that further compromised the parasites viability, linking protein aggregation to proteasome dysfunction. Changes in the distribution of aggregation-prone proteins, shown by the altered subcellular fluorescent pattern of the new investigational aggregated protein dye and antiplasmodial compound YAT2150 in the overexpressing P. falciparum line, highlighted the critical balance between protein aggregation, stress responses, and parasite viability, suggesting proteostasis-targeting therapies as a good antimalarial strategy.

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Bolognesi, Benedetta

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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

Protein aggregation is a pathological hallmark of more than 50 human diseases and a major problem for biotechnology. Methods have been proposed to predict aggregation from sequence, but these have been trained and evaluated on small and biased experimental datasets. Here we directly address this data shortage by experimentally quantifying the aggregation of >100,000 protein sequences. This unprecedented dataset reveals the limited performance of existing computational methods and allows us to train CANYA, a convolution-attention hybrid neural network that accurately predicts aggregation from sequence. We adapt genomic neural network interpretability analyses to reveal CANYA’s decision-making process and learned grammar. Our results illustrate the power of massive experimental analysis of random sequence-spaces and provide an interpretable and robust neural network model to predict aggregation.

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We have developed an inverted single-plane illumination microscope adapted for the interrogation of intestinal epithelium organ-on-chip devices. In this kind of system, samples are normally scanned in a slow fashion through motorized stages. Here, we have engineered a faster sample remote focusing scan mode by the use of an electro-tunable lens synchronized with Galvo mirrors, overcoming some limitations of previous systems. In addition, we have also engineered and optimized scaffolds recapitulating the 3D topography of the intestinal epithelium. Finally, we evaluated the performance of the system using fixed and in-vitro intestinal epithelium organ-on-chip devices, demonstrating the possibility of live imaging for several hours without distorting sample evolution.

JTD Keywords: Crypt, Lgr, Light-sheet microscopy, Stem-cells

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.

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Bacterial infections pose a significant global health challenge aggravated by the rise of antimicrobial resistance (AMR). Among the obstacles preventing effective treatment are biological barriers (BBs) within the body such as the mucus layer. These BBs trap antimicrobials, necessitating higher doses and ultimately accelerating AMR. Addressing this issue requires innovative therapeutic strategies capable of bypassing BBs to deliver drugs more effectively. Here, we present nanomotors (NMs) based on hyaluronic acid (HA)- and urease-nanogels (NGs) as a solution to navigate effectively in viscous media by catalyzing the decomposition of urea into ammonium and carbon dioxide. These HA-based nanomotors (HA-NMs) were loaded with chloramphenicol (CHL) antibiotic and demonstrated superior antimicrobial activity against Escherichia coli(E. coli) compared to mesoporous silica NMs (MSNP-NMs), a reference in the field of NMs. Moreover, using an in vitro transwell model we evaluated the ability of HA-NMs to penetrate mucin barriers, effectively reducing E. coli proliferation, whereas the free antibiotic did not reduce bacteria proliferation. The optical density reduction at 24 h was over ten times greater than with free CHL. These organic-based enzyme-powered NMs represent a significant advancement in drug delivery, offering a promising approach to combat AMR while addressing the challenges of crossing complex BBs.

JTD Keywords: Bacterial infections, Biologicalbarriers, Design, Drug deliver, Enzyme, Mucu, Nanogels, Nanomotors, Nanoparticles

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

Cells are sensitive to the physical properties of their microenvironment and transduce them into biochemical cues that trigger gene expression and alter cell behavior. Numerous proteins, including integrins, are involved in these mechanotransductive events. Here, a novel role for the boron transporter NaBC1 is identified as a mechanotransducer. It is demonstrated that soluble boron ions activate NaBC1 to enhance cell adhesion and intracellular tension in C2C12 myoblasts seeded on fibronectin-functionalized polyacrylamide (PAAm) hydrogels. Retrograde actin flow and traction forces exerted by these cells are significantly increased in vitro in response to both increased boron concentration and hydrogel stiffness. These effects are fibronectin and NaBC1-mediated as they are abrogated in hydrogels coated with laminin-111 in place of fibronectin and in esiRNA NaBC1-silenced cells. These findings thus demonstrate that NaBC1 controls boron homeostasis and also functions as a mechanosensor.

JTD Keywords: Activation, Animals, Beta-1-integrin, Biomaterials, Boron, Cell adhesion, Cell line, Cell-matrix, Differentiation, Fibronectins, Focal adhesion kinase, Growth, Hydrogels, Integrins, Mechanobiology, Mechanotransduction, Mechanotransduction, cellular, Mediated adhesion, Mice, Muscle cells, Myoblasts, Nabc1, Skeletal-muscle, Stiffnes, Tissue engineerin, Tissue engineering

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

Macrophages are crucial in the body's inflammatory response, with tightly regulated functions for optimal immune system performance. Our study reveals that the RAS-p110 alpha signalling pathway, known for its involvement in various biological processes and tumourigenesis, regulates two vital aspects of the inflammatory response in macrophages: the initial monocyte movement and later-stage lysosomal function. Disrupting this pathway, either in a mouse model or through drug intervention, hampers the inflammatory response, leading to delayed resolution and the development of more severe acute inflammatory reactions in live models. This discovery uncovers a previously unknown role of the p110 alpha isoform in immune regulation within macrophages, offering insight into the complex mechanisms governing their function during inflammation and opening new avenues for modulating inflammatory responses.

JTD Keywords: Actin, Cytoskeleton, Differential expression analysis, Inflammation, Inhibition, Macrophages, Monocytes, Nf-kappa-b, P110-alpha isoform, Pathwa, Ras, Ras-p110 alph, Recruitment

Human pluripotent stem cells hold inherent properties, allowing researchers to recapitulate key morphogenetic processes. These characteristics, coupled with bioengineering techniques, have led to the definition of early procedures to derive organ-like cell cultures, the so-called organoids. With regard to kidney organoids, challenges stand ahead, such as the need to enhance cellular composition, maturation, and function to that found in the native organ. To this end, the kidney organoid field has begun to nourish from innovative engineering approaches aiming to gain control on the externally imposed biochemical and biophysical cues. In this review, we first introduce how previous research in kidney development and human pluripotent stem cells has informed the establishment of current kidney organoid procedures. We then discuss recent engineering approaches to guide kidney organoid self-organization, differentiation, and maturation. In addition, we present current strategies to engineer vascularization and promote in vivo–like physiological microenvironments as potential solutions to increase kidney organoid lifespan and functionality. We finally emphasize how working at the cusp of cell mechanics and computational biology will set the ground for successful translational applications of kidney organoids.

JTD

Duah-Quashie, Nancy O.

JTD

Drug targeting can be achieved by coupling drugs or their carriers to affinity molecules, mostly antibodies (Abs), which recognise specific protein targets. However, most proteins are not expressed in an exclusive configuration but as various isoforms. Hence, selected targeting molecules may fail to target with enough efficiency in clinical trials, which is overlooked. We illustrate this by targeting intercellular adhesion molecule 1 (ICAM-1), a cell-surface protein overexpressed in many pathologies. Most ICAM-1 targeting studies used Ab R6.5, which binds ICAM-1 domain 2 (D2). Yet, literature and our data show that D2 is frequently absent among ICAM-1 isoforms. We thus produced a battery of five new Abs (B4, B6, B11, C12 and G2) and tested their ability to recognise both full-length and -D2 ICAM-1. In solution, all Abs recognised both ICAM-1 forms (from 5.3 x 1011 to 4.2 x 1012 sum intensity/well). Coating them on nanocarriers (NCs) rendered G2 specific against -D2 ICAM-1 (4.2 x 106 NCs/well) while other Abs kept their dual recognition (from 6.4 x 106 to 2.2 x 107 NCs/well). All Abs induced NC intracellular uptake in respective cells (from 42% to 85%) and displayed good cross-species reactivity (from 4.4 x 1011 to 2.6 x 1012 sum intensity/well). These Abs represent valuable tools to target ICAM-1 and illustrate a new targeting paradigm that may improve classical strategies.

JTD Keywords: Adhesion, Antibody-targeted nanocarriers, Cross-species reactivit, Design, Domai, Endothelial delivery, Enlimomab, Icam-1, Icam-1 isoforms, Intercellular adhesion molecule 1, Nanocarriers, Nanoparticles, New recombinant antibodies, Pecam-1, Targeting and intracellular trafficking

Lopes, Cátia D. F.

JTD

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, Optogeneticphotostimulation, Primary visual-cortex, Voltage indicator, Wavefrontshaping

Background/aims: Human mesenchymal stromal cells (hMSC) are multipotent adult cells commonly used in regenerative medicine as advanced therapy medicinal products. The expansion of these cells in xeno-free supplements is highly encouraged by regulatory agencies due to safety concerns. However, the number of supplements with robust performance and consistency for hMSC expansion are limited. Here, we evaluate a xeno-free human plasma-derived protein supplement (Plastem, Grifols) for the expansion and functional evaluation of hMSCs. Methods: hMSC from bone marrow, adipose tissue and umbilical cord were obtained from two suppliers and cultured in Dulbecco's modified Eagle's medium (DMEM/F-12) supplemented with fetal bovine serum 10% (FBS), human platelet lysate 5% (hPL) or Plastem 10%+ hPL0.5%. Cell proliferation was evaluated after culturing hMSC for 13 days with trypan blue exclusion. hMSC immunophenotype was assessed by flow cytometry of surface markers expression. Multipotentiality assay determined the ability of hMSC to differentiate into osteogenic, chondrogenic and adipogenic lineages after 21 days, by using specific staining. Immunomodulatory properties of hMSC were analyzed by measuring suppression of human peripheral blood mononuclear cell (PBMC) proliferation in co-culture with hMSC. Results: Plastem 10% + hPL 0.5% supported robust and sustained hMSC growth with a similar efficiency to the reference supplement FBS 10%. hMSC cultured with the xeno-free supplement presented a similar morphology comparable to FBS-supplemented cells and maintained typical expression of markers: positive (>95%) for CD90, CD73 and CD105; and negative (

JTD Keywords: Animal serum, Bone-marrow, Cell culture media, Cell therapy manufacturing, Expansion, Human mesenchymal stromal cells, Human platelet lysate, Immunomodulation, International-society, Multipotentiality, Proliferation, Serum-free media, Stem-cells, Substitut, Therapy, Xeno-fre

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

Cancer ranks as a leading cause of death worldwide, with liver cancer being one of the most commonly diagnosed. Currently, several molecules are being studied in order to find new therapeutic options that can reduce cancer recurrence rate and increase patient survival. This study proposes PEGylated liposomes for the delivery of a newly synthesized aminohydroxy sulfonamide, BupM-NH2, which has shown dose-dependent cytotoxicity towards hepatic tumor cells. The prepared PEG-liposomes were nanosized, spherical, and unilamellar, as shown by light scattering data and cryo-TEM micrographs. The physical stability of the PEG-liposomes was preserved when tested in simulated body fluids. Similar results were found for the storage stability evaluation. Furthermore, the PEG-liposomes efficiently entrapped BupM-NH2 and modulated its release. The antitumor activity of BupM-NH2 in PEG-liposomes was assessed in vitro in hepatocarcinoma cells. The viability assay showed that PEG-liposomes were able to control the release of BupM-NH2 over time and induce the death of HepG2 cells at a concentration about two-times lower than that required by free BupM-NH2 (IC50: 33.31 vs. 57.05 mu M). Furthermore, the liposomal formulation showed a less cytotoxic effect against non-cancerous cell line (IHH) compared to the free molecule (IC50 > 200 vs. 106.9 mu M), encouraging further investigation to confirm its effective and safe use.

JTD Keywords: Aminohydroxy sulfonamide, Anticancer formulation, Cancer, Delivery-systems, Drug-delivery, Hepatic cancer cells, Parenteral delivery, Peg-modified liposomes, Pegylated liposomes, Stability

The structure and dynamics of important biological quasi-two-dimensional systems, ranging from cytoskeletal gels to tissues, are controlled by nematic order, flow, defects and activity. Continuum hydrodynamic descriptions combined with numerical simulations have been used to understand such complex systems. The development of thermodynamically consistent theories and numerical methods to model active nemato-hydrodynamics is eased by mathematical formalisms enabling systematic derivations and structured-preserving algorithms. Alternative to classical nonequilibrium thermodynamics and bracket formalisms, here we develop a theoretical and computational framework for active nematics based on Onsager's variational formalism to irreversible thermodynamics, according to which the dynamics result from the minimization of a Rayleighian functional capturing the competition between free-energy release, dissipation and activity. We show that two standard incompressible models of active nemato-hydrodynamics can be framed in the variational formalism, and develop a new compressible model for density-dependent active nemato-hydrodynamics relevant to model actomyosin gels. We show that the variational principle enables a direct and transparent derivation not only of the governing equations, but also of the finite element numerical scheme. We exercise this model in two representative examples of active nemato-hydrodynamics relevant to the actin cytoskeleton during wound healing and to the dynamics of confined colonies of elongated cells.

JTD Keywords: Active nematics, Bracket formulation, Equations, Finite element metho, Hydrodynamics, Instabilities, Model, Nematic defects, Onsager's variational formalism, Principle, Wound healing

The limited efficacy shown by drug delivery systems so far prompts the development of new molecular approaches for releasing drugs in a controlled and selective manner. Light is a privileged stimulus for delivery because it can be applied in sharp spatiotemporal patterns and is orthogonal to most biological processes. Supramolecular polymers form molecular nanostructures whose robustness, versatility, and responsivity to different stimuli have generated wide interest in materials chemistry. However, their application as drug delivery vehicles has received little attention. We built supramolecular polymers based on discotic amphiphiles that self-assemble in linear nanostructures in water. They can integrate diverse amphiphilic bioligands and release them upon illumination, acutely producing functional effects under physiological conditions. We devised two strategies for drug incorporation into the photoswitchable nanofibers. In the co-assembly strategy, discotic monomers with and without conjugated bioligands were co-assembled in helicoidal supramolecular fibers. In the drug embedding approach, we integrated a potent agonist of muscarinic receptors into the discotic polymer by noncovalent stacking interactions. This ligand can be released on demand with light ex situ and in situ, rapidly activating the target receptor and triggering intracellular responses. These novel discotic supramolecular polymers can be light-driven drug carriers for small, planar, and amphiphilic drugs.

JTD Keywords: Delivery, Doxorubicin, Glutamate-receptor, Nanoparticles, Nanostructures, Optical control, Paclitaxe

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

Roca-Cusachs, Pere

JTD

Arborescent (dendrigraft) polymers are high-molecular-weight dendritic macromolecules with a regular, multilevel branched topology and a high density of functional end groups in their periphery. Their well-defined architecture, devoid of cross-links or loops, imparts a particle-macromolecule duality that becomes particularly pronounced at interfaces. However, the underlying mechanisms governing their interfacial behavior remain largely unexplored. Here, we elucidate how the unique topology dictates the interfacial organization of water-soluble arborescent polymers. Using an iterative grafting-from approach via single-electron transfer living radical polymerization, we synthesized narrowly dispersed polymers with controlled branching and ultra-high molecular weight of 6.2 x 106 g mol-1. These polymers transition from spherical rigid particles in solution, to highly flexible, two-dimensional conformations upon interfacial adsorption. At solid interfaces, increasing segment density shifts surface morphologies from quasi-2D discs to fried-egg-like structures, as observed by atomic force microscopy and corroborated by dissipative particle dynamics simulations. At liquid-liquid interfaces, the absence of substrate constraints facilitates complete spreading into uniform 2D discs, driven by the energy gain due to polymer-segment adsorption. Furthermore, we uncover that macromolecular crowding and topological constraints inherent to the arborescent architecture dictate the response to compression of the adsorbed polymer layer, contrasting sharply with the behavior of conventional flexible linear or star polymers. The combination of high interfacial activity, spatially adaptable end groups, and extreme molecular flexibility will enable arborescent polymers to adapt to complex interfaces, acting as versatile platforms for multivalent and superselective interactions. These properties open new avenues for designing multivalent nanocarriers and adaptive interfacial materials with cooperative binding effects.

JTD Keywords: Angle neutron-scattering, Architectur, Graft, Microgels, Polymers, Polystyrene-graft-poly(2-vinylpyridine) copolymers, Polystyrenes, Radical polymerization, Set, Unimolecular micelles

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

Montero, Joan

JTD

In this study, the extraction process of grape pomace from the Lebanese autochthonous cultivar Asswad Karech was enhanced through the selection of specific parameters, yielding an antioxidant extract (20 mg/mL) that was co-loaded with resveratrol (5 mg/mL) into phospholipid vesicles containing penetration enhancers (PEVs). Propylene glycol (PG) was incorporated as a penetration enhancer at concentrations of 10, 20, and 30 % to obtain 10 PG-PEVs, 20 PG-PEVs, and 30 PG-PEVs. Vesicle preparation was achieved through direct sonication, yielding unilamellar and bilamellar vesicles with an average size of similar to 205; 234 nm, a monodisperse distribution (polydispersity index

JTD Keywords: By-product valorisation, Cigarette smoke, Delivery, Dru, Grape pomace extract, In-vitro, Liposomes, Lung deliver, Oxidative stress, Phospholipids vesicles

Pons, Miquel

JTD

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

Visser, W. Edward

JTD

Silica-based nanoparticles have been extensively investigated as advanced bioimaging probes and smart nanocarriers for the development of nanomedicine because of their unique properties. The deep understanding of nanoparticle-biological system (nanobiology) interactions is an important determinant for the success of nanomedicine. In this Review, we focus on the assessment of significant nanobio interactions along with the intracellular fates of silica-based nanoparticles by advanced microscopy and link this information to their recent biomedical applications. Initially, the fundamental concepts of the dynamic interactions between nanoparticles and proteins followed by cells and key factors that influence these nanobio interactions are briefly introduced. Furthermore, the basic principles of advanced imaging modalities for the analysis of nanobio interactions in this study are described. Next, the utilization of advanced imaging for the characterization of protein coronas and monitoring the cellular internalization and intracellular trafficking/fate of individual nanoparticles are comprehensively summarized. Finally, recent biomedical applications of nanoparticles in bioimaging and drug delivery are discussed.

JTD Keywords: Adsorption, Cellular uptake, Desig, Drug-delivery, Mesoporous organosilica nanoparticles, Nanocapsules, Protein corona, Size, Superresolution microscopy, Surface-properties

The urgent need for safer and innovative antitubercular agents remains a priority for the scientific community. In pursuit of this goal, we designed and evaluated novel 5-phenylfuran-2-carboxylic acid derivatives targeting Mycobacterium tuberculosis (Mtb) salicylate synthase (MbtI), a key enzyme, absent in humans, that plays a crucial role in Mtb virulence. Several potent MbtI inhibitors demonstrating significant antitubercular activity and a favorable safety profile were identified. Structure-guided optimization yielded 5-(3-cyano-5-isobutoxyphenyl)furan-2-carboxylic acid (1e), which exhibited strong MbtI inhibition (IC50 = 11.2 mu M) and a promising in vitro antitubercular activity (MIC99 = 32 mu M against M. bovis BCG). Esters of 1e were effectively loaded into poly(2-methacryloyloxyethyl phosphorylcholine)-poly(2-(diisopropylamino)ethyl methacrylate) (PMPC-PDPA) polymersomes (POs) and delivered to intracellular mycobacteria, resulting in reduced Mtb viability. This study provides a foundation for the use of POs in the development of future MbtI-targeted therapies for tuberculosis.

JTD Keywords: Chemistry, Discovery, Drug-delivery, Insigh, Polymersomes, Salicylate synthase mbti, Siderophore, Strategies, Target, Visualization

Odorant discrimination mechanisms are based on the differential interactions between odorant molecules and olfactory receptors (ORs). Biohybrid sensors based on ORs described to date show selectivity towards specific versus non-specific binding of odorants, being unable to distinguish between specific ligands of different affinity. Here we disclose a method that enables odorant discrimination based on the modulation of the capacitive response of the receptor, which allows the differentiation of three high-affinity hOR1A1 agonists. We performed voltammetry and impedance measurements of the hOR1A1 receptor selectively immobilized on a gold electrode in the absence and presence of the agonists. Binding induces a decrease in the capacitive response of the receptor that is proportional to the ligand potency, reaching up to a 40% decrease for the cognate ligand dihydrojasmone, which is attributed to changes in the magnitude and orientation of the electric dipole in the receptor, thereby regulating its response to the applied electric field.

JTD Keywords: Agonist, Biosenso, Electric dipol, Electrochemical impedance spectroscopy, Impedance, Nose, Odorant receptors, Olfactory receptor, Selectivity, Specific capacitance

Objectives: Despite the high survival rates of dental implants, peri-implantitis is a prevalent complication. Periimplantitis is related to biofilm that adheres to the surface of implants and causes peri-implant chronic inflammation and bone destruction. Different surface treatments have been proposed to prevent biofilm formation. The objective of this systematic review was analyzing different types of antimicrobial coatings and identifying the most effective one(s) to control bacterial colonization over extended periods of analysis. Data, sources and study selection: We performed a bibliographic search in Pubmed and Cochrane base of articles published after 2010 to answer, according to the PICO system, the following question: What is the most effective antibacterial surface coating for dental implants? Only papers including a minimum follow-up bacteria growth analysis for at least 48 h were selected. After selection, the studies were classified using the PRISMA system. A total of 40 studies were included. Conclusions: Three main categories of coatings were identified: Antibacterial peptides, synthetic antimicrobial molecules (polymers, antibiotics, ...), and metallic nanoparticles (silver). Antibacterial peptide coatings to modify dental implant surfaces have been the most studied and effective surface modification to control bacterial colonization over extended periods of incubation as they are highly potent, durable and biocompatible. However, more in vitro and pre-clinical studies are needed to assess their true potential as a technology for preventing periimplant infections.

JTD Keywords: Anti-infective coating, Antibiotics, Antimicrobial peptide coatings, Antimicrobial peptides, Antimicrobial polymers, Bacterial colonizatio, Biofilm formatio, Cationic peptides, Chimeric peptides, Dental implants, Human gingival fibroblasts, Metal nanoparticles, Osseointegrated oral implants, Peri-implantitis, Silver nanoparticles, Surface treatment, Sustained-release device, Titanium surfaces

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

Acetylcholine and the cholinergic system are crucial to brain function, including functions such as consciousness and cognition. Dysregulation of this system is implicated in the pathophysiology of neurological conditions such as Alzheimer's disease. For this reason, cholinergic neuromodulation is relevant in both basic neuroscience and clinical neurology. In this study, we used photopharmacology to modulate neuronal activity using the novel selective type-1 muscarinic (M1) photoswitchable drugs: the agonist benzyl quinolone carboxylic acid-azo-iperoxo (BAI) and the antagonist cryptozepine-2. Our aim was to investigate the control over these cholinergic receptors using light and to investigate the effects of these drugs on physiological spontaneous slow waves and on epileptic activity in the cerebral cortex. First, we used transfected HEK cell cultures and demonstrated BAI's preferential activation of M1 muscarinic acetylcholine receptors (mAChRs) compared with M2 mAChRs. Next, we found that white-light illumination of BAI increased the frequency of spontaneous slow-wave activity in brain cortical networks of both active slices and anesthetized mice, through M1-mAChRs activation. Illumination of cryptozepine-2 with UV light effectively suppressed not only the muscarinic-induced increase in slow-wave frequency, but also muscarinic-induced epileptiform discharges. These findings not only shed light on the role of M1 acetylcholine receptors in the cortical network dynamics but also lay the groundwork for developing advanced light-based pharmacological therapies. Photopharmacology offers the potential for high-precision spatiotemporal control of brain networks with high pharmacological specificity in both healthy and pathological conditions.

JTD Keywords: Acetylcholine, Acetylcholine-receptors, Biological health and medical sciences, Brain, Epilepsy, Hz oscillation, Less-than-1 hz, Modulation, Network mechanisms, Neuromodulation, Neuroscienc, Pathology, Photopharmacology, Seizures, Slee, Slow oscillations

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

Cell membranes play a key role in bottom-up synthetic biology, as they enable interaction control, transport, and other essential functions. These ultra-thin, flexible, yet stable structures form through the self-assembly of lipids and proteins. While liposomes are common mimics, their synthetic membranes often fail to replicate natural properties due to poor structural control. To address this, pepticombs are introduced, a new family of supramolecular building blocks. They are synthesized by regularly appending anionic surfactants with lipid-long alkyl tails to cationic amino acid residues of recombinant elastin-like supercharged unfolded polypeptides (SUPs). Using microscopy techniques and molecular dynamics simulations, the formation of giant unilamellar vesicles, termed pepticombisomes, is demonstrated and their membrane properties are characterized. The molecular topology of pepticombs allows for precise mimicry of membrane thickness and flexibility, beyond classic polymersomes. Unlike the previously introduced ionically-linked comb polymers, all pepticombs exhibit a uniform degree of polymerization, composition, sequence, and spontaneous curvature. This uniformity ensures consistent hydrophobic tail distribution, facilitating intermolecular hydrogen bonding within the backbone. This generates elastic heterogeneities and the concomitant formation of non-icosahedral faceted vesicles, as previously predicted. Additionally, pepticombisomes can incorporate functional lipids, enhancing design flexibility.

JTD Keywords: Biomimetic synthesis, Bottom-up synthetic biology, Cholesterol, Dynamics, Glycodendrimersomes, Janus dendrimers, Lipids, Nanoscal, Organization, Polymersome membranes, Protein, Stability, Supercharged peptides, Synthetic cells, Vesicle

A multiplexed microarray chip (Immuno-mu SARS2) aiming at providing information on the prognosis of the COVID-19 has been developed. The diagnostic technology records information related to the profile of the immunological response of patients infected by the SARS-CoV-2 virus. The diagnostic technology delivers information on the avidity of the sera against 28 different peptide epitopes and 7 proteins printed on a 25 mm2 area of a glass slide. The peptide epitopes (12-15 mer) derived from structural proteins (Spike and Nucleocapsid) have been rationally designed, synthesized, and used to develop Immuno-mu SARS2 as a multiplexed and high-throughput fluorescent microarray platform. The analysis of 755 human serum samples (321 from PCR+ patients; 288 from PCR- patients; 115 from prepandemic individuals and classified as hospitalized, admitted to intensive-care unit (ICU), and exitus) from three independent cohorts has shown that the chips perform with a 98% specificity and 91% sensitivity identifying RT-PCR+ patients. Computational analysis utilized to correlate the immunological signatures of the samples analyzed indicate significant prediction rates against exitus conditions with 82% accuracy, ICU admissions with 80% accuracy, and 73% accuracy over hospitalization requirement compared to asymptomatic patients' fingerprints. The miniaturized microarray chip allows simultaneous determination of 96 samples (24 samples/slide) in 90 min and requires only 10 mu L of sera. The diagnostic approach presented for the first time here could have a great value in assisting clinicians in decision-making based on the information provided by the Immuno-mu SARS2 regarding progression of the disease and could be easily implemented in diagnostics of other infectious diseases.

JTD Keywords: Antibodies, Clinical diagnostic, Diagnosis, High-throughput, Machine learning, Microarray, Multiplexation, Nucleocapsid protein, Peptide epitopes, Sars-cov-, Sars-cov-2, Serological signature, Seroprevalence, Severity prediction, Spik

Metabolism in biological systems involves the continuous formation and breakdown of chemical and structural components, driven by chemical energy. In specific, metabolic processes on cellular membranes result in in situ formation and degradation of the constituent phospholipid molecules, by consuming fuel, to dynamically regulate the properties. Synthetic analogs of such chemically fueled phospholipid vesicles have been challenging. Here we report a bio-inspired approach for the in situ formation of phospholipids, from water soluble precursors, and their fuel driven self-assembly into vesicles. We show that the kinetic competition between anabolic and catabolic-like reactions leads to the formation and enzymatic degradation of the double-tailed, vesicle-forming phospholipid. Spectroscopic and microscopic analysis demonstrate the formation of transient vesicles whose lifetime can be easily tuned from minutes to hours. Importantly, our design results in the formation of uniform sized (65 nm) vesicles simply by mixing the precursors, thus avoiding the traditional complex methods. Finally, our sub-100 nm vesicles are of the right size for application in drug delivery. We have demonstrated that the release kinetics of the incorporated cargo molecules can be dynamically regulated for potential applications in adaptive nanomedicine.

JTD Keywords: Droplets, Mode, Phospholipids, Supramolecular chemistry, Systems chemistry, Transient assembl, Vesicles

Flexible and biocompatible strain sensors are becoming increasingly important in fields such as health monitoring, wearable electronics, and environmental sensing because they offer significant advantages over conventional rigid systems. However, they lack the versatility and ecological and physiological biocompatibility necessary for broader integration within biological systems. Here, we describe the development of an inexpensive water-based plasticized chitosan-carbon black composite ink that can be used to produce conductive and biocompatible strain sensors. The ink can be applied to various surfaces, including skin, internal organs, and other biological tissues, using numerous methods, such as painting, dipping, and stamping. Furthermore, this unprecedented ability to attach and conform to biological surfaces allows the exploration of secondary sensing innovations, such as exploiting skin wrinkles to improve sensitivity. This study demonstrates that the ink exhibits a reliable change in electrical resistance in response to a wide range of motions, from subtle vibrations during speech and heartbeats to extensive articulations, like finger and elbow movements. This exceptional sensitivity range, biocompatibility, and the ink's low cost, biodegradability, and ease of removal enhance its applicability in sustainable, temporary, and customizable sensing solutions, highlighting its potential for versatile applications in human health monitoring, motion detection, and environmental sensing.

JTD Keywords: Blac, Chitin, Composites, Performance strain sensors

The Boston keratoprosthesis (BKPro) is a critical device for vision restoration in complex cases of corneal blindness, although its long-term retention is challenged by infection risks. This study aims to enhance the antimicrobial properties of the titanium (Ti) backplate of the BKPro by ion implanting silver and copper ions to achieve effective infection control while maintaining cytocompatibility. Research on antimicrobial modifications for BKPro is limited, and while metallic ions like Ag and Cu show promise for biomaterial improvement, their effects on human corneal keratocytes (HCKs) require further study. Ag and Cu were implanted onto rough Ti surfaces, as mono- and coimplantations. Cytotoxicity was assessed in HCKs, and antimicrobial efficacy was tested against Pseudomonas aeruginosa and Candida albicans. After 21 d, monoimplanted Ag samples released 300.4 ppb of Ag+, coimplanted samples released 427.5 ppb of Ag+ and 272.3 ppb of Cu ions, and monoimplanted Cu samples released 567.0 ppb of Cu ions. All ion-implanted surfaces supported HCK proliferation, exhibited no cytotoxicity, and showed strong antimicrobial activity. Ag-implanted surfaces provided antibacterial effects through membrane disruption and reactive oxygen species generation, while Cu-implanted surfaces exhibited antifungal effects via impaired enzymatic functions and reactive oxygen species. Coimplanted AgCu surfaces demonstrated synergistic antimicrobial effects, resulting from the synergy between the bactericidal actions of Ag and the oxidative stress contributions of Cu. Additionally, ion-implanted surfaces enhanced HCK adhesion under co-culture conditions. In conclusion, ion implantation effectively imparts antimicrobial properties to the Ti backplate of BKPro, reducing infection risks while preserving compatibility with corneal cells.

JTD Keywords: Endophthalmitis, Mechanisms, Nanoparticle, Silver

Extracellular matrix (ECM) viscoelasticity has emerged as a potent regulator of physiological and pathological processes, including cancer progression. Spatial confinement within the ECM is also known to influence cell behavior in these contexts. However, the interplay between matrix viscoelasticity and spatial confinement in driving epithelial cell mechanotransduction is not well understood, as it relies on experiments employing purely elastic hydrogels. This work presents an innovative approach to fabricate and micropattern viscoelastic polyacrylamide hydrogels with independently tuneable Young's modulus and stress relaxation, specifically designed to mimic the mechanical properties observed during breast tumor progression, transitioning from a soft dissipative tissue to a stiff elastic one. Using this platform, this work demonstrates that matrix viscoelasticity differentially modulates breast epithelial cell spreading, adhesion, YAP nuclear import and cell migration, depending on the initial stiffness of the matrix. Furthermore, by imposing spatial confinement through micropatterning, this work demonstrates that confinement alters cellular responses to viscoelasticity, including cell spreading, mechanotransduction and migration. These findings establish ECM viscoelasticity as a key regulator of epithelial cell mechanoresponse and highlight the critical role of spatial confinement in soft, dissipative ECMs, which was a previously unexplored aspect.

JTD Keywords: Cell adhesion, Cell movement, Confinement, Dynamics, Elastic modulus, Elasticity, Epithelial cells, Extracellular matrix, Extracellular-matrix, Force transmission, Humans, Hydrogels, Mechanics, Mechanotransduction, cellular, Micropatterning, Migration, Morphology, Motilit, Polyacrylamide hydrogels, Stiffness, Substrate, Viscoelasticit, Viscoelasticity, Viscosity

The chemical and physical stability of bio-hydrogels are of utmost interest to avoid the premature degradation of the polymer and to favor cyclic material operations (i.e., material recovery and re-using). In this work, the stability of different alginate hydrogels semi-interpenetrated with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate conducting polymer (Alg/PEDOT), which acts as a photothermal absorber is examined. More specifically, the behavior of Alg/PEDOT hydrogels ionically and covalently crosslinked with Ca2+ ions and glyoxal, respectively, has been compared when used as water purification platforms. The homogenous porosity and higher cycling capacity of the glyoxal-crosslinked gels provide superior performance for water-steam generation under sunlight irradiation than that of the ionically stabilized gel. Furthermore, increasing the glyoxal cross-linking reaction time prove to have little effect on the porosity and the efficiency of freshwater supply from an artificial seawater solution. Covalent cross-links provide thermal absorber (PEDOT:PSS) retention capacity in artificial seawater, which is critical to maintaining such efficiency with the increasing number of purification cycles. This research opens new frontiers to promote the use of alginate biopolymer in chemical engineering processes such as water desalination, directly addressing the United Nations Sustainable Development Goals for Clean Water & Life on Land.

JTD Keywords: 4-ethylenedioxythiophene, Alginate polysaccharide, Cell delivery, Glyoxal, Interpenetrating hydrogel network, Poly(3, Raman-spectroscopy, Sodium alginate, Tissu

In serology, each sample is typically tested individually, one antigen at a time. This is costly and time consuming. Serology techniques should ideally allow recurrent measurements in parallel in small sample volumes and be inexpensive and fast. Here we show that mass cytometry can be used to scale up multiplexed serology testing by leveraging polystyrene beads uniformly loaded with combinations of stable isotopes. We generated 18,480 unique isotopically barcoded beads to simultaneously detect, in a single tube with 924 serum samples, the levels of immunoglobulins G and M against 19 proteins from SARS-CoV-2 (a total of 36,960 tests in 400 nl of sample volume and 30 mu l of reaction volume). As a rapid, high-throughput and cost-effective technique, serology by mass cytometry may contribute to the effective management of public health emergencies originating from infectious diseases.

JTD Keywords: Antibodies, viral, Biolog, Covid-19, Covid-19 serological testing, Cytometer, High-throughput screening assays, Humans, Immunoglobulin g, Immunoglobulin m, Mass spectrometry, Microspheres, Polystyrenes, Sars-cov-2, Transmission

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

Historical processes in community assembly, such as species arrival order, influence interactions, causing priority effects. Candida albicans and Pseudomonas aeruginosa often co-occur in biofilm-based infections of the skin, lungs, and medical devices. Their predominantly antagonistic relationship involves complex physical and chemical interactions. However, the presence and implications of priority effects among these microorganisms remain largely unexplored. Here, we investigate the presence and impact of priority effect in dual-species biofilms using clinical isolates. By varying inoculation order, we observe significant changes in biofilm composition, structure, virulence, and antimicrobial susceptibility. The first colonizer has an advantage for surface colonization. Consecutive colonization increases biofilm virulence and negates C. albicans' protective effect on P. aeruginosa PAET1 against meropenem treatment. Finally, we propose N-acetylcysteine as an adjuvant for treating C. albicans and P. aeruginosa interkingdom infections, working independently of priority effects.

JTD Keywords: Airway colonization, Bacteria, Infections, Pneumonia, Spp., Virulenc

Intercellular adhesion molecule-1 (ICAM-1) is a membrane protein whose expression is enhanced at pathological sites, supporting drug delivery using nanocarriers (NCs). Any of its five extracellular domains (D1 to D5) can be targeted, yet most NC studies have used antibody (Ab) R6.5, which targets domain D2. While this provided efficient NC targeting and intracellular transport, literature indicates the absence of D2 in about 50 % of ICAM-1 isoforms expressed in mouse models. In this study, we verified the presence of ICAM-1 isoforms lacking D2 in human cells at both mRNA and protein levels, supporting the need to test Abs targeting other ICAM-1 domains. We developed a new cell model specifically lacking ICAM-1 D2 and compared R6.5 to Abs targeting D1 (Ab 15.2), D3D4 (Ab G-5), and D5 (Ab H-4). Abs G-5 and H-4 showed best targeting results, for which they were coated on model polymeric NCs. Compared to non-specific IgG NCs, both anti-ICAM-1 formulations targeted recombinant cells expressing human ICAM-1 lacking D2 and also primary cells naturally expressing the whole ICAM-1 isoform pattern observed. Both formulations were efficiently internalized by cells and trafficked to lysosomes, as previously observed for ICAM-1-targeting systems. Furthermore, NCs coated with either one of these two Abs showed good cross-species reactivity, being amenable for future pre-clinical testing. Therefore, Abs G-5 or H-4 are good options to provide ICAM-1 targeting without missing ICAM-1 isoforms lacking D2, present in human.

JTD Keywords: Adhesion molecule-1 icam-1, Anti-icam-1 antibody, Antibody-targeted nanocarriers, Design, Different receptor epitopes, Domai, Endothelial delivery, Enlimomab, Icam-1 extracellular domains, Icam-1 isoforms, Identification, Intercellular adhesion molecule 1, Monoclonal-antibodies, Nanoparticles, Targeting and endocytosi, Transport

The sustainable synthesis of urea from ammonia (NH3) and carbon dioxide (CO2) using ultraporous permanently polarized hydroxyapatite (upp-HAp) as catalyst has been explored as an advantageous CO2-revalorization strategy. As the simultaneous activation of N-2 and CO2 (single-step) demands an increase of the reaction conditions, we have re-visited the industrial two-step Bazarov reaction. upp-HAp has been designed as a stable multifunctional catalyst capable of promoting both CO2 and NH3 adsorption for their subsequent C-N bond formation. Herein we report the synthesis of 1 mmol/g(cat) of urea with a selectivity of 97 % under strictly mild conditions (95-120 degrees C and 1 bar of CO2; without applying any electrical currents or UV irradiation) which represents an efficiency of similar to 2 % and similar to 30 % with respect to the NH3 and CO2 content, respectively. The study of the NH3 content, products adsorbed in the catalyst, presence of intermediates and temperature of the reaction allows unveiling the great potential of upp-HAp as a green catalyst for sustainable Bazarov reactions. Results suggest that the double-step approach could be more advantageous for both synthesizing urea and as a CO2-revalorization strategy, which in turn promotes the development of specific technologies for the independent synthesis of green NH3.

JTD Keywords: Co2-revalorization, Hydroxyapatite, Permanently polarized materials, Tsp treatment, Ure, Urea

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

Gas sensor-based electronic noses (e-noses) have gained considerable attention over the past thirty years, leading to the publication of numerous research studies focused on both the development of these instruments and their various applications. Nonetheless, the limited specificity of gas sensors, along with the common requirement for chemical identification, has led to the adaptation and incorporation of analytical chemistry instruments into the e-nose framework. Although instrument-based e-noses exhibit greater specificity to gasses than traditional ones, they still produce data that require correction in order to build reliable predictive models. In this work, we introduce the use of a multivariate signal processing workflow for datasets from a multi-capillary column ion mobility spectrometer-based e-nose. Adhering to the electronic nose philosophy, these workflows prioritized untargeted approaches, avoiding dependence on traditional peak integration techniques. A comprehensive validation process demonstrates that the application of this preprocessing strategy not only mitigates overfitting but also produces parsimonious models, where classification accuracy is maintained with simpler, more interpretable structures. This reduction in model complexity offers significant advantages, providing more efficient and robust models without compromising predictive performance. This strategy was successfully tested on an olive oil dataset, showcasing its capability to improve model parsimony and generalization performance.

JTD Keywords: Breath, Chromatography, Classification, Electronic nose, Hs-gc-ims, Ion mobility spectrometry, Mcc-ims-based e-nose, Olive oi, Olive oil, Parsimony, Preprocessing, Quality control, Selection, Signal processing workflow, System, Too, Validation, Wavelet

Dementia affects a large proportion of the world's population. Approaches that allow for early disease detection and non-invasive monitoring of disease progression are desperately needed. Current approaches are centred on costly imaging technologies such as positron emission tomography and magnetic resonance imaging. We propose an alternative approach to assess neurodegeneration based on diffuse correlation spectroscopy (DCS), a remote and optical sensing technique. We employ this approach to assess neurodegeneration in mouse brains from healthy animals and those with prion disease. We find a statistically significant difference in the optical speckle decor relation times between prion-diseased and healthy animals. We directly calibrated our DCS technique using hydrogel samples of varying Young's modulus, indicating that we can optically measure changes in the brain tissue stiffness in the order of 60 Pa (corresponding to a 1 s change in speckle decor relation time). DCS holds promise for contact-free assessment of tissue stiffness alteration due to neurodegeneration, with a similar sensitivity to contact-based (e.g. nanoindentation) approaches.

JTD Keywords: Correlation spectroscopy, Decorrelation time, Disease, In-vivo, Magnetic-resonance elastography, Prion neurodegeneration, Tomograph

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

The intricate interactions between the host immune system and its microbiome constituents undergo dynamic shifts in response to perturbations to the intestinal tissue environment. Our ability to study these events on the systems level is significantly limited by in situ approaches capable of generating simultaneous insights from both host and microbial communities. Here, we introduce Microbiome Cartography (MicroCart), a framework for simultaneous in situ probing of host and microbiome across multiple spatial modalities. We demonstrate MicroCart by investigating gut host and microbiome changes in a murine colitis model, using spatial proteomics, transcriptomics, and glycomics. Our findings reveal a global but systematic transformation in tissue immune responses, encompassing tissue-level remodeling in response to host immune and epithelial cell state perturbations, bacterial population shifts, localized inflammatory responses, and metabolic process alterations during colitis. MicroCart enables a deep investigation of the intricate interplay between the host tissue and its microbiome with spatial multi-omics.

JTD Keywords: Animals, Bacteria, Cellular microenvironment, Colitis, Design, Disease models, animal, Environment, Fis, Gastrointestinal microbiome, Glycomics, Host microbial interactions, Intestinal mucosa, Intestines, Male, Mice, Mice, inbred c57bl, Multiomics, Organization, Probes, Proteins, Proteomics, Rna, Subcellular resolution, Transcriptome

Nanoparticle (NP) morphology holds significant importance in nanomedicine, particularly concerning its implications for biological responses. This study investigates the impact of synthesizing polymers with varying degrees of methionine (MET) polymerization on three distinct drug delivery systems: spherical micelles, worm-like micelles, and vesicles, all loaded with the photosensitizer chlorin e6 (Ce6). We analyzed their distribution at both cellular and animal levels, revealing how NP morphology influences cellular uptake, subcellular localization, penetration of multicellular spheroids, blood half-life, and biodistributions across major organs. Employing a physiologically based pharmacokinetic (PBPK) model enabled us to simulate diverse distribution patterns and quantify the targeting efficiency of NPs toward tumors. Our investigation elucidates that spherical micelles exhibit lower accumulation levels within the reticuloendothelial system, potentially mitigating adverse side effects despite their higher glomerular filtration rate. This nuanced understanding underscores the complex interplay between NP morphology and biological responses, providing valuable insights into optimizing therapeutic efficacy while minimizing undesirable effects. We thus report the integration of experimental analyses with PBPK modeling to elucidate the topological characteristics of NP, thereby shedding light on their distribution patterns, therapeutic efficacy, and potential side effects.

JTD Keywords: Drug, Nanorod, Polymersomes, Strategies

The global dental implant market is projected to reach $9.5 billion by 2032, growing at a 6.5% compound annual growth rate due to the rising prevalence of dental diseases. Importantly, this growth raises concerns about postoperative infections, which present significant challenges within our healthcare system and lead to a two-thirds failure rate for infected implants. In this study, we present an innovative multilevel coating system that makes the surface of dental titanium implants resistant to bacterial colonization, thereby minimizing the risk of infection development. This multilevel coating features a nanometer-thick biohybrid coating layer combined with a microgroove surface microstructuring, creating physical barriers that enhance the stability of the biohybrids against mechanical abrasion. Our coating demonstrates excellent biocompatibility and strong antifouling properties against undiluted blood plasma proteins. Furthermore, the combination of surface microstructuring and the biohybrid coating remains stable under prolonged mechanical stress simulation and effectively repels clinically relevant bacteria, achieving a 99% reduction in bacterial colonization on the implant. These findings underscore the potential of this approach to prevent implant-associated infections and highlight the critical role of surface engineering in ensuring long-term implant performance.

JTD Keywords: Antifouling, Bacteriarepellency, Biofilm formatio, Dental titanium implants, Infection preventio, Protein-polymer biohybrids, Ti-binding peptide, Usp laser microstructuring

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

Mechanical forces influence mitochondrial dynamics through previously unexplored mechanisms. A new study demonstrates that actomyosin tension inhibits mitochondrial fission by phosphorylating a key component of the fission complex and that this event regulates the nuclear accumulation of critical transcription factors.

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With the aim of healing challenging skin wounds, electro-responsive click-hydrogels made of hyaluronic acid (clickHA) crosslinked with a modified polyethylene glycol precursor (PEG) were prepared by semi- interpenetrating a conducting polymer, poly(hydroxymethyl-3,4-ethylenedioxythiophene) (PEDOT-MeOH) by oxidative polymerization. The porosity and pore size of the mixed hydrogel, clickHA/PEDOT-MeOH, were both higher than those determined for the hydrogel without PEDOT-MeOH, while a honeycomb-like morphology with PEDOT-MeOH covering the pore walls was observed. Although such PEDOT-MeOH-induced changes did not influence the water absorption capacity of clickHA, they drastically affected the mechanical and electrochemical behavior. More specifically, the semi-interpenetration of PEDOT-MeOH into clickHA resulted in an increase of the Young's modulus, the compressive strength and, especially, the electrochemical activity. The biocompatibility and the potential for skin regeneration of clickHA/PEDOT-MeOH were preliminary assessed using viability and wound-healing assays with epithelial cells. Not only is the conducting hydrogel formulation biocompatible, but also promotes efficient cell migration by electrostimulation using a small voltage (0.5 V) for a short time (15 min). Thus, in just 1 h the wound gap was repaired, and a homogeneous monolayer of migrated cells was formed.

JTD Keywords: 4-ethylenedioxythiophene, Car, Click hydrogel, Conducting polymer, Hyaluronic acid, Poly(3, Proliferation, Rational design, Scaffold, Skin, Wound dressing

Nuclear magnetic resonance (NMR) spectroscopy is a valuable diagnostic tool limited by low sensitivity due to low nuclear spin polarization. Hyperpolarization techniques, such as dissolution dynamic nuclear polarization, significantly enhance sensitivity, enabling real-time tracking of cellular metabolism. However, traditional high-field NMR systems and bioreactor platforms pose challenges, including the need for specialized equipment and fixed sample volumes. This study introduces a scalable, 3D-printed bioreactor platform compatible with low-field NMR spectrometers, designed to accommodate bioengineered 3D cell models. The bioreactor is fabricated using biocompatible materials and features a microfluidic system for media recirculation, ensuring optimal culture conditions during NMR acquisition and cell maintenance. We characterized the NMR compatibility of the bioreactor components and confirmed minimal signal distortion. The bioreactor's efficacy was validated using HeLa and HepG2 cells, demonstrating prolonged cell viability and enhanced metabolic activity in 3D cultures compared to 2D cultures. Hyperpolarized [1-13C] pyruvate experiments revealed distinct metabolic profiles for the two cell types, highlighting the bioreactor's ability to discern metabolic profiles among samples. Our results indicate that the bioreactor platform supports the maintenance and analysis of 3D cell models in NMR studies, offering a versatile and accessible tool for metabolic and biochemical research in tissue engineering. This platform bridges the gap between advanced cellular models and NMR spectroscopy, providing a robust framework for future applications in nonspecialized laboratories. The design files for the 3D printed components are shared within the text for easy download and customization, promoting their use and adaptation for further applications.

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Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide and greatly reduces the quality of life. Utilizing remote monitoring has been shown to improve quality of life and reduce exacerbations, but remains an ongoing area of research. We introduce a novel method for estimating changes in ease of breathing for COPD patients, using obstructed breathing data collected via wearables. Physiological signals were recorded, including respiratory airflow, acceleration, audio, and bio-impedance. By comparing patient-specific measurements, this approach enables non-intrusive remote monitoring. We analyze the influence of signal selection, window parameters, feature engineering, and classification models on predictive performance, finding that acceleration signals are most effective, complemented by audio signals. The best model achieves an F1-score of 0.83. To facilitate clinical adoption, we incorporate interpretability by designing novel saliency map methods, highlighting important aspects of the signals. We adapt local explainability techniques to time series and introduce a novel imputation method for periodic signals, improving faithfulness to the data and interpretability.

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Blood-contacting medical devices, especially extracorporeal membrane oxygenators (ECMOs), are highly susceptible to surface-induced coagulation because of their extensive surface area. This can compromise device functionality and lead to life-threatening complications. High doses of anticoagulants, combined with anti-thrombogenic surface coatings, are typically employed to mitigate this risk, but such treatment can lead to hemorrhagic complications. Therefore, bioactive surface coatings that mimic endothelial blood regulation are needed. However, evaluating these coatings under realistic ECMO conditions is both expensive and challenging. This study utilizes microchannel devices to simulate ECMO fluid dynamics and assess the clot-lysis efficacy of a self-activating fibrinolytic coating system. The system uses antifouling polymer brushes combined with tissue plasminogen activator (tPA) to induce fibrinolysis at the surface. Here, tPA catalyzes the conversion of blood plasminogen into plasmin, which dissolves clots. This positive feedback loop enhances clot digestion under ECMO-like conditions. This findings demonstrate that this coating system can significantly improve the hemocompatibility of medical device surfaces.

JTD

Bio-nano interactions have been extensively explored in nanomedicine to develop selective delivery strategies and reduce systemic toxicity. To enhance the delivery of nanocarriers to cancer cells and improve the therapeutic efficiency, different nanomaterials have been developed. However, the limited clinical translation of nanoparticle-based therapies, largely due to issues associated with poor targeting, requires a deeper understanding of the biological phenomena underlying cell-nanoparticle interactions. In this context, we investigate the molecular and cellular mechanobiology parameters that control such interactions. We demonstrate that the pharmacological inhibition or the genetic ablation of the key mechanosensitive component of the Hippo pathway, i.e., yes-associated protein, enhances nanoparticle internalization by 1.5-fold. Importantly, this phenomenon occurs independently of nanoparticle properties, such as size, or cell properties such as surface area and stiffness. Our study reveals that the internalization of nanoparticles in target cells can be controlled by modulating cell mechanosensing pathways, potentially enhancing nanotherapy specificity.

JTD Keywords: Bio-nano interactions, Comple, Mechanobiology, Mechanotransductio, Nanoparticles, Yap/taz

The tumor microenvironment (TME) comprises a heterogenous cell population within a complex threedimensional (3D) extracellular matrix (ECM). Stromal cells within this TME are altered by signaling cues from cancer cells to support uncontrolled tumor growth and invasion events. Moreover, the ECM also plays a fundamental role in tumor development through pathological remodeling, stiffening and interaction with TME cells. In healthy tissues, Hippo signaling pathway actively contributes to tissue growth, cell proliferation and apoptosis. However, in cancer, the Hippo signaling pathway is highly dysregulated, leading to nuclear translocation of the YAP/TAZ complex, which directly contributes to uncontrolled cell proliferation and tissue growth, and ECM remodeling and stiffening processes. Here, we compare the effect of increasing cell culture substrate stiffness, derived from tumor progression, upon the dysregulation of the Hippo signaling pathway in colorectal cancer-associated fibroblasts (CAFs) and normal colorectal fibroblasts (NFs). We correlate the dysregulation of Hippo pathway with the magnitude of the traction forces exerted by healthy and malignant stromal cells. We found that ECM stiffening is crucial in Hippo pathway dysregulation in CAFs, but not in normal fibroblasts.

JTD Keywords: Cancer-associated fibroblasts, Hippo pathway, Organ size control, Tissu, Tumor microenvironment, Yap-ta, Yap/taz

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