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The evolution of endovascular therapies, particularly in the field of intracranial aneurysm treatment, has been truly remarkable and is characterized by the development of various stents. However, ischemic complications related to thrombosis or downstream emboli pose a challenge for the broader clinical application of such stents. Despite advancements in surface modification technologies, an ideal coating that fulfills all the desired requirements, including anti-thrombogenicity and swift endothelialization, has not been available. To address these issues, we investigated a new coating comprising 3-aminopropyltriethoxysilane (APTES) with both anti-thrombogenic and cell-adhesion properties. We assessed the anti-thrombogenic property of the coating using an in vitro blood loop model by evaluating the platelet count and the level of the thrombin-antithrombin (TAT) complex, and investigating thrombus formation on the surface using scanning electron microscopy (SEM). We then assessed endothelial cell adhesion on the metal surfaces. In vitro blood tests revealed that, compared to a bare stent, the coating significantly inhibited platelet reduction and thrombus formation; more human serum albumin spontaneously adhered to the coated surface to block thrombogenic activation in the blood. Cell adhesion tests also indicated a significant increase in the number of cells adhering to the APTES-coated surfaces compared to the numbers adhering to either the bare stent or the stent coated with an anti-fouling phospholipid polymer. Finally, we performed an in vivo safety test by implanting coated stents into the internal thoracic arteries and ascending pharyngeal arteries of minipigs, and subsequently assessing the health status and vessel patency of the arteries by angiography over the course of 1 week. We found that there were no adverse effects on the pigs and the vascular lumens of their vessels were well maintained in the group with APTES-coated stents. Therefore, our new coating exhibited both high anti-thrombogenicity and cell-adhesion properties, which fulfill the requirements of an implantable stent.

Trichomonas vaginalis, a common sexually transmitted parasite that colonizes the human urogenital tract, secretes extracellular vesicles (TvEVs) that are taken up by human cells and are speculated to be taken up by parasites as well. While the crosstalk between TvEVs and human cells has led to insight into host:parasite interactions, roles for TvEVs in infection have largely been one-sided, with little known about the effect of TvEV uptake by T. vaginalis. Approximately 11% of infections are found to be coinfections of multiple T. vaginalis strains. Clinical isolates often differ in their adherence to and cytolysis of host cells, underscoring the importance of understanding the effects of TvEV uptake within the parasite population. To address this question, our lab tested the ability of a less adherent strain of T. vaginalis, G3, to take up fluorescently labeled TvEVs derived from both itself (G3-EVs) and TvEVs from a more adherent strain of the parasite (B7RC2-EVs). Here, we showed that TvEVs generated from the more adherent strain are internalized more efficiently compared to the less adherent strain. Additionally, preincubation of G3 parasites with B7RC2-EVs increases parasite aggregation and adherence to host cells. Transcriptomics revealed that TvEVs up-regulate expression of predicted parasite membrane proteins and identified an adherence factor, heteropolysaccharide binding protein (HPB2). Finally, using comparative proteomics and superresolution microscopy, we demonstrated direct transfer of an adherence factor, cadherin-like protein, from TvEVs to the recipient parasites surface. This work identifies TvEVs as a mediator of parasite:parasite communication that may impact pathogenesis during mixed infections.

The retina is exquisitely patterned, with neuronal somata positioned at regular intervals to completely sample the visual field. Here, we show that phosphatase and tensin homolog (Pten) controls starburst amacrine cell spacing by modulating vesicular trafficking of cell adhesion molecules and Wnt proteins. Single-cell transcriptomics and double-mutant analyses revealed that Pten and Down syndrome cell adhesion molecule Dscam) are co-expressed and function additively to pattern starburst amacrine cell mosaics. Mechanistically, Pten loss accelerates the endocytic trafficking of DSCAM, FAT3, and MEGF10 off the cell membrane and into endocytic vesicles in amacrine cells. Accordingly, the vesicular proteome, a molecular signature of the cell of origin, is enriched in exocytosis, vesicle-mediated transport, and receptor internalization proteins in Pten conditional knockout (PtencKO) retinas. Wnt signaling molecules are also enriched in PtencKO retinal vesicles, and the genetic or pharmacological disruption of Wnt signaling phenocopies amacrine cell patterning defects. Pten thus controls vesicular trafficking of cell adhesion and signaling molecules to establish retinal amacrine cell mosaics.

RhoU and RhoV are members of the Rho family of small GTPases that comprise their own subfamily. RhoUV GTPases are classified as atypical due to the kinetics of their GTP/GDP binding cycles. They also possess unique N- and C-termini that regulate their subcellular localization and activity. RhoU and RhoV have been linked to cytoskeletal regulation, cell adhesion, and cell migration. They each exhibit distinct expression patterns during embryonic development and diseases such as cancer metastasis, suggesting they have specialized functions. In this review, we will discuss the known functions of RhoU and RhoV, with a focus on their roles in early development, organogenesis, and disease.

Integrin mechanosensing plays an instrumental role in cell behavior, phenotype, and fate by transmitting mechanical signals that trigger downstream molecular and cellular changes. For instance, force transfer along key amino acid residues can mediate cell adhesion. Disrupting key binding sites within α 5 β 1 integrin's binding partner, fibronectin (FN) diminishes adhesive strength. While past studies have shown the importance of these residues in cell adhesion, the relationship between the dynamics of these residues and how integrin distributes force across the cell surface remains less explored. Here, we present a multiscale mechanical model to investigate the mechanical coupling between integrin nanoscale dynamics and whole-cell adhesion mechanics. Our framework leverages molecular dynamics simulations to investigate residues within α 5 β 1 -FN during stretching and the finite element method to visualize the whole-cell adhesion mechanics. The forces per integrin across the cell surface of the whole-cell model were consistent with past atomic force microscopy and Förster resonance energy transfer measurements from the literature. The molecular dynamics simulations also confirmed past studies that implicate two key sites within FN that maintain cell adhesion: the synergy site and arginine-glycine-aspartic acid (RGD) motif. Our study contributed to our understanding of molecular mechanisms by which these sites collaborate to mediate whole-cell integrin adhesion dynamics. Specifically, we showed how FN unfolding, residue binding/unbinding, and molecular structure contribute to α 5 β 1 -FN's nonlinear force–extension behavior during stretching. Our computational framework could be used to explain how the dynamics of key residues influence cell differentiation or how uniquely designed protein structures could dynamically limit the spread of metastatic cells. [ABSTRACT FROM AUTHOR]

The development of ectodermal organs begins with the formation of a stratified epithelial placode that progressively invaginates into the underlying mesenchyme as the organ takes its shape. Signaling by secreted molecules is critical for epithelial morphogenesis, but how that information leads to cell rearrangement and tissue shape changes remains an open question. Using the mouse dentition as a model, we first establish that non-muscle myosin II is essential for dental epithelial invagination and show that it functions by promoting cell-cell adhesion and persistent convergent cell movements in the suprabasal layer. Shh signaling controls these processes by inducing myosin II activation via AKT. Pharmacological induction of AKT and myosin II can also rescue defects caused by the inhibition of Shh. Together, our results support a model in which the Shh signal is transmitted through myosin II to power effective cellular rearrangement for proper dental epithelial invagination.

Nano‐hydroxyapatite (nano‐HAP)/poly (l‐lactic acid) (PLLA) bone scaffold is expected to overcome the deficiencies and achieve the complementary advantages of individual constituents, but the weak interfacial bonding due to their thermodynamic incompatibility is detrimental to the mechanical properties. Herein, the PLLA chains were grafted onto nano‐HAP with 3‐aminopropyltriethoxysilane (KH550) as a coupling reagent to enhance the interfacial bonding with PLLA. Specifically, the silicon hydroxyl group produced by KH550 hydrolysis could form covalent bonding with the hydroxyl group of nano‐HAP, and the amino group of KH550 initiated the ring‐opening polymerization of l‐lactide monomers to graft PLLA chains onto nano‐HAP more effectively, leading to a higher grafting ratio of 16.7% compared with 7.2% in direct grafting without KH550 modification. Consequently, the tensile and compressive strength of the modified nano‐HAP/PLLA scaffold were improved by 40.8% and 59.5% enhancement due to the enhanced interfacial bonding in the composite scaffold, respectively, compared to the original nano‐HAP/PLLA scaffold. Additionally, the bone scaffold was conducive to cell adhesion and proliferation, making it an ideal candidate for bone defect repair. Highlights: Amino‐functionalized nano‐HAP boosted the grafting efficiency of PLLA chains.Interfacial bonding between nano‐HAP and matrix was enhanced.Bone scaffold showed better mechanical properties and benign cytocompatibility. [ABSTRACT FROM AUTHOR]

In this article, site‐specific functionalized keratoprosthesis (KPro) was accomplished to meet epithelial on‐growth on the anterior optical surface, inhibit cell adhesion on the posterior optic surface, and promote cell ingrowth at the peripheral tissue‐haptic‐flange interface toward tissue integration. Gelatin immobilization on PC4 hydrogel surfaces was achieved through acid hydrolysis followed by EDC/NHS chemistry, and polyethylene glycol‐diacrylate (PEGDA)‐modified inter‐penetrating network (IPN) surfaces were prepared using photo‐polymerization of ethylene glycol‐diacrylate (EGDA) for enhancing and inhibiting cellular growth, respectively. The surface chemical structures of modified hydrogels were characterized using attenuated total reflectance‐infrared (ATR‐IR) spectroscopy and a bicinchoninic acid (BCA) protein adsorption assay. Further, suitable differentially functionalized surfaces were prepared and characterized using the universal testing machine (UTM), refractometer, atomic force microscopy (AFM), and contact angle measurements to understand mechanical, optical, surface morphological, and wettability properties, respectively. Finally, in vitro site‐specific cell adhesion, cell inhibition, and cell ingrowth functionalities were tested using isolated goat corneal limbal epithelial stem cells and corneal stromal fibroblast cells, respectively. Overall, the two connective articles represent a successful endeavor to develop a more esthetically pleasing, mechanically stable, tissue‐free hydrogel KPro with site‐specific surface functionality nearly mimicking the cornea's functionality. A further pre‐clinical investigation is necessary to advance this functional novel KPro to reality, especially the tissue integration aspect. [ABSTRACT FROM AUTHOR]

The glycocalyx is a complex layer of carbohydrate and protein molecules that surrounds the cell membrane of many types of mammalian cells. It serves several important functions, including cell adhesion and communication, and maintain cell shape and stability, especially in the case of erythrocytes. Alteration of glycocalyx composition represents a cardiovascular health threatening. For example, in diabetes mellitus glycocalyx of erythrocytes and of endothelial cells is known to be impaired, a potential source of blood occlusion in microcirculation, which may lead to blindness, and renal failure of patients. The impact of glycocalyx impairment on erythrocyte aggregation remains a largely unexplored research area. We conduct here in vitro-experiments in microfluidic devices in order to investigate erythrocytes aggregation incubated with amylase, an enzyme that partially breaks down glycocalyx molecules. It is found that incubation of erythrocytes by amylase leads to a dramatic increase of their aggregation and stability and alters the aggregates morphologies. Confocal microscopy analysis reveals a significant degradation of the glycocalyx layer, correlated with enhanced erythrocytes aggregation. An increased erythrocyte aggregation in vivo should affect oxygen and other metabolites delivery to organs and tissues. This study brings new elements about elucidation of microscopic origins of erythrocyte aggregation and their potential impact on cardiovascular pathologies. [ABSTRACT FROM AUTHOR]

Introduction: Neutrophil extracellular traps (NETs) are complex structures released by activated neutrophils that may modulate different steps of the metastatic cascade. The aim of our study was to investigate how NETs can modulate the adhesion properties of cancer cells and whether cell exposure to NETs can activate the epithelial-to-mesenchymal transition (EMT) program thus enhancing the migratory and invasive properties of tumor cells. Materials and methods: Different cancer cell lines were subjected to a solidphase adhesion assay using NET-coated plates with or without the addition of antibodies against α5β1 or CCDC25 receptor. After 1-4 h of incubation, adherent cells were expressed as the percentage of total cell number. To test EMT occurrence, cells were treated with NETs for up to 48 h and then the levels of E-cadherin, vimentin, Snail, Slug, Zeb 1 and Twist 1 along with levels of Notch 1 and cleaved Notch 1 were determined by western blotting. Untreated and NETtreated cells were subjected to migration assays using 24-multiwell plates with transwell and FBS as chemoattractant. Results: Cancer cell adhesion to NET-coated plates varied between 30% and 92.7% and was significantly higher than that obtained in uncoated plates. The addition of antibodies against α5β1 or CCDC25 caused a strong reduction of cell adhesion to NETs. The prolonged exposure of EGFR-driven cancer cell lines to NETs caused the activation of the EMT program through the upregulation and cleavage of Notch 1 and was confirmed by the enhanced expression of EMT markers. The consequent loss of the epithelial phenotype induced a strong reduction of the expression of the oncogene driver. Cell migration was significantly enhanced in NET-treated cells as compared to untreated cells. Discussion: Our findings reveal the dynamic role of NETs that may provide a DNA and fibronectin rich environment for binding of many cancer cells at distant sites where the prolonged exposure to NETs triggers the EMT through the activation of Notch 1 signaling pathway with the subsequent enhancement of migratory and invasive properties of cancer cells. Furthermore, our findings provide an example of how an immune/inflammatory microenvironment may directly modulate the sensitivity of cancer cells to oncogene targeted agents. [ABSTRACT FROM AUTHOR]

In this study, a three-layer small diameter artificial vascular graft with a structure similar to that of natural blood vessels was first constructed by triple-step electrospinning technology, in which polylactic acid (PLA) and collagen (COL) were used for the inner layer, polylactic acid and polycaprolactone (PCL) was used for the middle layer and polycaprolactone and gelatin was used for the outer layer. The properties of the artificial vascular graft were adjusted by the EDC/NHS cross-linking agent through the reaction between the collagen or gelatine and EDC/NHS. The mechanical and hydrophilic properties of the cross-linked artificial vessels were substantially enhanced, with a maximum stress of 9.56 MPa in the axial direction and 9.31 MPa in the radial direction for the P/C (4:1) vascular graft, which exceeded that of many textile-based and natural vascular grafts. The increased hydrophilicity of the inner layer of the vessel before crosslinking was due to the addition of COL, and the inner layer of the artificial vessel after crosslinking had a substantial increase in hydrophilicity due to the production of a more hydrophilic urea derivative. The increased hydrophilicity led to easier cell adhesion to the inner layer of the artificial vessel, especially for the P/C (2:1) vascular graft, where the cell proliferation rate and adhesion were high due to COL incorporation and cross-linking. The three-layer vascular grafts studied did not lead to haemolysis. Therefore, the EDC/NHS cross-linked three-layer vascular graft had good mechanical properties, hydrophilicity, anticoagulation and could enhance cell adhesion and proliferation. [ABSTRACT FROM AUTHOR]

The ability of the attaching and effacing pathogens enterohaemorrhagic Escherichia coli (EHEC) and Citrobacter rodentium to overcome colonisation resistance is reliant on a type 3 secretion system used to intimately attach to the colonic epithelium. This crucial virulence factor is encoded on a pathogenicity island known as the Locus of Enterocyte Effacement (LEE) but its expression is regulated by several core-genome encoded transcription factors. Here, we unveil that the core transcription factor PdhR, traditionally known as a regulator of central metabolism in response to cellular pyruvate levels, is a key activator of the LEE. Through genetic and molecular analyses, we demonstrate that PdhR directly binds to a specific motif within the LEE master regulatory region, thus activating type 3 secretion directly and enhancing host cell adhesion. Deletion of pdhR in EHEC significantly impacted the transcription of hundreds of genes, with pathogenesis and protein secretion emerging as the most affected functional categories. Furthermore, in vivo studies using C. rodentium, a murine model for EHEC infection, revealed that PdhR is essential for effective host colonization and maximal LEE expression within the host. Our findings provide new insights into the complex regulatory networks governing bacterial pathogenesis. This research highlights the intricate relationship between virulence and metabolic processes in attaching and effacing pathogens, demonstrating how core transcriptional regulators can be co-opted to control virulence factor expression in tandem with the cell's essential metabolic circuitry. Author summary: This study reveals an unexpected role for a metabolic regulatory protein in the attaching and effacing family of pathogenic Gram-negatives. The transcription factor PdhR normally functions by repressing expression of the pyruvate dehydrogenase complex in response to cellular pyruvate levels, thus helping cells to manage their energy production. However, we discovered that PdhR is also capable of controlling the ability of these pathogens to colonise host cells early in infection. Deletion of pdhR affected the transcription of hundreds of genes, including many involved in the infection process. As such, PdhR was found to be required for host cell attachment both in vitro and in vivo. This level of control is achieved by a mechanism involving direct interaction between PdhR and the gene region encoding a key pathogen virulence factor. This discovery highlights how bacteria can re-purpose proteins involved in basic processes of life to control their ability to cause disease, showing that the connection between a bacterial metabolism and pathogenesis is more complex than previously thought. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms of assembly and disassembly of macromolecular structures in cells relies on solving biomolecular interactions. However, those interactions often remain unclear because tools to track molecular dynamics are not sufficiently resolved in time or space. In this study, we present a straightforward method for resolving inter‐ and intra‐molecular interactions in cell adhesive machinery, using quantum dot (QD) based Förster resonance energy transfer (FRET) nanosensors. Using a mechanosensitive protein, talin, one of the major components of focal adhesions, we are investigating the mechanosensing ability of proteins to sense and respond to mechanical stimuli. First, we quantified the distances separating talin and a giant unilamellar vesicle membrane for three talin variants. These variants differ in molecular length. Second, we investigated the mechanosensing capabilities of talin, i.e., its conformational changes due to mechanical stretching initiated by cytoskeleton contraction. Our results suggest that in early focal adhesion, talin undergoes stretching, corresponding to a decrease in the talin‐membrane distance of 2.5 nm. We demonstrate that QD‐FRET nanosensors can be applied for the sensitive quantification of mechanosensing with a sub‐nanometer accuracy. [ABSTRACT FROM AUTHOR]

Porous zirconia scaffolds manufactured using polymer-infiltrated ceramic network (PICN) and additive manufacturing technologies are emerging as promising alternatives to traditional ceramic materials in dental restorations. However, incomplete osseointegration and bacterial infections still represent challenges for the long-term performance of this new composite material. To address this, the present study aims to investigate the effect of peptide biofunctionalization on the biological performance of infiltrated zirconia scaffold surfaces. The samples used in the work consisted of a 3D-printed zirconia scaffold infiltrated with a dimethacrylate copolymer. Surface biofunctionalization was achieved using a synthetic platform containing the cell-adhesive sequence RGD and the antibacteria LF1-11 peptide (RGD-LF). The attachment of the molecule was characterized through fluorescence confocal laser scanning microscopy and X-ray photoelectron spectroscopy. The biological performance of the samples was evaluated in terms of human mesenchymal stem cell adhesion and early attachment of S. aureus. The physicochemical characterization verified the successful anchoring of the biomolecule to the surface, leading to a peptide density of 288 pmol/cm2. The biological assays confirmed the potential of RGD-LF to improve cell adhesion and spreading. In this sense, the average cell area increased fourfold in the biofunctionalized surface. Regarding bacterial adhesion, it was demonstrated that RGD-LF significantly inhibited it, reducing early adhesion by half compared to the untreated surface. Overall, this study provides valuable insights into the biofunctionalization of polymer-infiltrated 3D scaffolds for the development of cell-instructive and antibacterial surfaces tailored for dental applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Classic Hodgkin lymphoma (CHL) is a highly curable disease, even in advanced stages. Controversy remains over whether bone involvement negatively affects overall and progression‐free survival in patients treated with intensive chemotherapy regimens. Whether cases that present with bone lesions harbor specific tumor microenvironmental features is unknown. We investigated protein expression in diagnostic lymph node biopsies from CHL patients with and without skeletal involvement at diagnosis to identify potential markers of skeletal disease. Protein expression patterns in diagnostic formalin‐fixed paraffin‐embedded lymphoma lymph node samples from CHL patients were analyzed by nano‐liquid chromatography–tandem mass spectrometry. Patients were grouped according to skeletal involvement, which was defined as the presence of one or more FDG‐avid lesions on a diagnostic FDG‐PET/CT scan. Protein profiles identified patients with skeletal disease at diagnosis and showed disrupted cellular pathways, including immune system processes, cell adhesion, and cell growth/survival. Immunohistochemical evaluation also demonstrated differential expressions of angiotensin‐converting enzyme (ACE), intercellular adhesion molecule 3 (ICAM3), integrin alpha‐X (ITGAX), and calreticulin (CALR). In conclusion, proteomics identified altered protein expression profiles in lymph nodes among CHL cases presenting with disease disseminated to the skeletal system, which implies altered disease pathogenesis for these patients. [ABSTRACT FROM AUTHOR]

The endometrium undergoes substantial remodeling in each menstrual cycle to become receptive to an implanting embryo. Abnormal endometrial receptivity is one of the major causes of embryo implantation failure and infertility. MicroRNA-124-3p is elevated in both the serum and endometrial tissue of women with chronic endometritis, a condition associated with infertility. MicroRNA-124-3p also has a role in cell adhesion, a key function during receptivity to allow blastocysts to adhere and implant. In this study, we aimed to determine the function of microRNA-124-3p on endometrial epithelial adhesive capacity during receptivity and effect on embryo implantation. Using a unique inducible, uterine epithelial-specific microRNA overexpression mouse model, we demonstrated that elevated uterine epithelial microRNA-124-3p impaired endometrial receptivity by altering genes associated with cell adhesion and polarity. This resulted in embryo implantation failure. Similarly in a second mouse model, increasing microRNA-124-3p expression only in mouse uterine surface (luminal) epithelium impaired receptivity and led to implantation failure. In humans, we demonstrated that microRNA-124-3p was abnormally increased in the endometrial epithelium of women with unexplained infertility during the receptive window. MicroRNA-124-3p overexpression in primary human endometrial epithelial cells (HEECs) impaired primary human embryo trophectoderm attachment in a 3-dimensional culture model of endometrium. Reduction of microRNA-124-3p in HEECs from infertile women normalized HEEC adhesive capacity. Overexpression of microRNA-124-3p or knockdown of its direct target IQGAP1 reduced fertile HEEC adhesion and its ability to lose polarity. Collectively, our data highlight that microRNA-124-3p and its protein targets contribute to endometrial receptivity by altering cell polarity and adhesion. [ABSTRACT FROM AUTHOR]

Implantable biomedical patch used in treating abdominal wall defects requires antibacterial, anti‐adhesion, and pro‐healing activities to ensure surgical success and prevent postsurgical complications. However, it often encounters challenges in fulfilling these three critical properties simultaneously, as these processes can always be contradictory during treatment. Herein, to break the barriers between bactericidal activity and cytocompatibility, cell adhesion and anti‐adhesion, a bio‐inspired patch with an asymmetric Janus structure is developed. This bio‐inspired Janus patch features cicada wing‐inspired nanostructures on its top surface, enabling both mechano–bactericidal effects and promotion of fibroblast adhesion and proliferation, which stems from its inherent "selective biocidal activity" toward bacteria and mammalian cells. Subsequently, a poly‐zwitterion layer with robust nonfouling properties is grafted on the bottom surface, realizing cell adhesion and anti‐adhesion on two sides of the same patch. Compared to the commercially available polypropylene (PP) meshes, the top surface of the Janus patch, which faces the abdominal wall, demonstrates superior capabilities in preventing postoperative infection and promoting tissue repair. Simultaneously, the other side facing the viscera efficiently prevents any visceral tissue adhesion. With these prominent performances, the bio‐inspired Janus patch presents a pioneering strategy for designing next‐generation patches to treat abdominal wall defects. [ABSTRACT FROM AUTHOR]

Objective: In this study we have focused on biocompatibility and osteoinductive capacity analysis of self-manufactured single-phase (HAP) and two-phase (HAP and β-ТСР) bioactive ceramics with various chemical modifications (Fig. 1). Results: We demonstrate a reduction in solubility for all analyzed composite after the treatment with H2O and H2O2, accompanied by an enhancement in adsorption activity. This modification also resulted in an increase in micro- and macroporosity, along with a rise in the open porosity. Adipose-derived mesenchymal stromal cells demonstrated excellent cell adhesion and survival when cultured with these ceramics. Calcium phosphate ceramics (H-500, HT-500, and HT-1 series) stimulated alkaline phosphatase expression, promoted calcium deposition, and enhanced osteopontin expression in ADSCs, independently inducing osteogenesis without additional osteogenic stimuli. These findings underscore the promising potential of HAP-based bioceramics for bone regeneration/reconstruction. [ABSTRACT FROM AUTHOR]

Biofilms are complex bacterial communities characterized by a high persister prevalence, which contributes to chronic and relapsing infections. Historically, persister formation in biofilms has been linked to constraints imposed by their dense structures. However, we observed an elevated persister frequency accompanying the stage of cell adhesion, marking the onset of biofilm development. Subsequent mechanistic studies uncovered a comparable type of toxin-antitoxin (TA) module (TA-like system) triggered by cell adhesion, which is responsible for this elevation. In this module, the toxin HipH acts as a genotoxic deoxyribonuclease, inducing DNA double strand breaks and genome instability. While the second messenger c-di-GMP functions as the antitoxin, exerting control over HipH expression and activity. The dynamic interplay between c-di-GMP and HipH levels emerges as a crucial determinant governing genome stability and persister generation within biofilms. These findings unveil a unique TA system, where small molecules act as the antitoxin, outlining a biofilm-specific molecular mechanism influencing genome stability and antibiotic persistence, with potential implications for treating biofilm infections. [ABSTRACT FROM AUTHOR]

Objective: To assess the predictive abilities of Doppler‐based resistive index and plasma biomarkers of endothelial cell activation in identifying persistent acute kidney injury (pAKI) among patients with septic shock. Method: Patients diagnosed with septic shock were categorized into none AKI (n = 25), transient AKI (tAKI, n = 47), and pAKI (n = 48) groups. Kidney function parameters (urine output, serum creatinine, and serum urea) were measured within the initial 24 h upon intensive care unit (ICU) admission. The Doppler‐based resistive index, and the plasma biomarkers [fractalkine, soluble E‐Selectin (sE‐Selectin), and soluble intercellular adhesion molecule‐1 (sICAM‐1)] were evaluated upon admission to the ICU. Results: The predictive capacity of Doppler‐based resistive index for distinguishing pAKI at day 3 from none AKI/tAKI in septic shock patients was moderate, with sensitivity of 47.92% and specificity of 76.39%. Fractalkine levels displayed significant differences across groups and exhibited a favorable predictive ability for pAKI at day 3 (AUC = 0.800), while sE‐Selectin and sICAM‐1 showed moderate predictive abilities (AUC = 0.636 and 0.634, respectively). Comparative analysis of predictive models demonstrated that incorporating kidney function parameters, Doppler‐based resistive index, and plasma biomarkers yielded the highest AUC of 0.903, followed closely by the model utilizing serum creatinine, urine output, and plasma fractalkine, with an AUC of 0.896. Conclusion: Integrating kidney function parameters, along with Doppler‐based resistive index and plasma biomarkers of endothelial cell activation, yielded the strongest predictive model for pAKI. Additionally, the combination of serum creatinine, urine output, and plasma fractalkine shows promise in risk assessment and management strategies for pAKI. [ABSTRACT FROM AUTHOR]

Obtaining a polymer nanocomposite with optimum viscoelastic, thermal, and biocompatibility properties is the main objective when designing nanocomposite systems with potential applications in tissue engineering. For this purpose, a blend of Polycaprolactone (PCL) and Polyvinylidene fluoride (PVDF) in an 85/15 weight ratio, along with a nanocomposite reinforced by nanohydroxyapatite (nHA) particles, is fabricated using a solution casting method in a mold. The impact of nHA content on crystallinity, viscoelastic properties, thermal stability, and the properties–structure relationship of nanocomposites is evaluated using scanning electron microscopy (SEM). Dynamic mechanical thermal (DMTA) analysis is used to determine the William–Landel–Ferry (WLF) constants and the effect of nHA on the nanocomposite's viscoelastic behavior. The PCL/15PVDF/0.5 wt% nHA exhibits the maximum thermal stability (40% residual char value) and 95% increase in storage modulus at 90 °C (rubbery region) in comparison with PCL/15PVDF blend. Water contact angle (WCA) and biocompatibility tests are conducted on the PCL/15PVDF blend and nanocomposite scaffolds to design appropriate nanocomposite systems with potential applications in tissue engineering. The high hydrophilic properties are assigned to PCL/15PVDF/0.5 wt% nHA with a WCA of 67.5°. Finally, in vitro cell culture confirmed 0.5 wt% nHA significantly improves cell adhesion and cytotoxicity with MG‐63 cells. [ABSTRACT FROM AUTHOR]

Recently, in vitro models emerge as valuable tools in biomedical research by enabling the investigation of complex physiological processes in a controlled environment, replicating some traits of interest of the biological tissues. This study focuses on the development of tubular polymeric scaffolds, made of electrospun fibers, aimed to generate three‐dimensional (3D) in vitro intestinal models resembling the lumen of the gut. Polycaprolactone (PCL) and polyacrylonitrile (PAN) are used to produce tightly arranged ultrafine fiber meshes via electrospinning in the form of continuous tubular structures, mimicking the basement membrane on which the epithelial barrier is formed. Morphological, physical, mechanical, and piezoelectric properties of the PCL and PAN tubular scaffolds are investigated. They are cultured with Caco‐2 cells using different biological coatings (i.e., collagen, gelatin, and fibrin) and their capability of promoting a compact epithelial layer is assessed. PCL and PAN scaffolds show 42% and 50% porosity, respectively, with pore diameters and size suitable to impede cell penetration, thus promoting an intestinal epithelial barrier formation. Even if both polymeric structures allow Caco‐2 cell adhesion, PAN fiber meshes best suit many requirements needed by this model, including highest mechanical strength upon expansion, porosity and piezoelectric properties, along with the lowest pore size. [ABSTRACT FROM AUTHOR]

Background Breast cancer brain metastasis is a rising occurrence, necessitating a better understanding of the mechanisms involved for effective management. Breast cancer brain metastases diverge notably from the primary tumor, with gains in kinase and concomitant losses of steroid signaling observed. In this study, we explored the role of the kinase receptor RET in promoting breast cancer brain metastases and provide a rationale for targeting this receptor. Methods RET expression was characterized in a cohort of patients with primary and brain metastatic tumors. RET functionality was assessed using pharmacological inhibition and gene silencing in patient-derived brain metastatic tumor explants and in vivo models, organoid models, and brain organotypic cultures. RNA sequencing was used to uncover novel brain metastatic relevant RET mechanisms of action. Results A statistically significant enrichment of RET in brain metastases was observed in estrogen receptor–positive breast cancer, where it played a role in promoting cancer cell adhesion, survival, and outgrowth in the brain. In vivo , RET overexpression enhanced brain metastatic competency in patient-derived models. At a mechanistic level, RET overexpression was found to enhance the activation of gene programs involved in cell adhesion, requiring EGFR cooperation to deliver a pro–brain metastatic phenotype. Conclusion Our results illustrate, for the first time, the role of RET in regulating colonization and outgrowth of breast cancer brain metastasis and provide data to support the use of RET inhibitors in the management strategy for patients with breast cancer brain metastases. [ABSTRACT FROM AUTHOR]

Australian saltbush (Atriplex spp.) survive in exceptionally saline environments and are often used for pasture in semi-arid areas. To investigate the impact of salinity on saltbush root morphology and root exudates, three Australian native saltbush species (Atriplex nummularia , Atriplex amnicola , and Atriplex vesicaria) were grown in vitro in optimised sterile, semi-hydroponic systems in media supplemented with different concentrations of salt (NaCl). Histological stains and chromatographic techniques were used to characterise the root apical meristem (RAM) type and root exudate composition of the saltbush seedlings. We report that saltbush species have closed-type RAMs, which release border-like cells (BLCs). Monosaccharide content, including glucose and fructose, in the root mucilage of saltbush was found to be uniquely low, suggesting that saltbush may minimise carbon release in polysaccharides of root exudates. Root mucilage also contained notable levels of salt, plus increasing levels of unidentified compounds at peak salinity. Un-esterified homogalacturonan, xyloglucan, and arabinogalactan proteins between and on the surface of BLCs may aid intercellular adhesion. At the highest salinity levels, root cap morphology was altered but root:shoot ratio remained consistent. While questions remain about the identity of some components in saltbush root mucilage other than the key monosaccharides, this new information about root cap morphology and cell surface polysaccharides provides avenues for future research. Australian saltbush (Atriplex spp.), used for pasture in semi-arid areas, survive in exceptionally salty environments, but little is known about how salinity affects the root morphology and root exudates. We discovered that saltbush have closed-type root apical meristems and release limited sugars as root exudates, maintaining root:shoot ratio even at extreme salinity. These findings offer new insights into saltbush resilience and encourage further research into their unique root properties. [ABSTRACT FROM AUTHOR]

The effective replication of microtubular structures in tissue engineering remains a great challenge. In this study, the temperature‐responsive characteristics of poly(N‐isopropylacrylamide) (pNIPAM) to create intricate, high‐resolution tubular structures through a shrinking mechanism is investigated by exploring 2 thermosensitive hydrogels–gelatin methacryloyl (gelMA) and silk fibroin methacryloyl (silkMA)–combined with pNIPAM. Systematic investigations revealed precise control of shrinking behavior at elevated temperatures (33–37 °C) as a function of polymer concentration. The hydrogel sizes reduce by ≈15% from room temperature (RT) to 33 °C and ≈40% from RT to 37 °C for both hydrogel types. The shrinking affects the mechanical properties, increasing the compressive modulus by ≈2.8‐fold for gelMA‐pNIPAM gels and ≈5.1‐fold for silkMA‐pNIPAM gels at 37 °C. Combined with volumetric printing, these materials achieve resolution enhancements of ≈20% for positive features and ≈70% for negative features, enabling the creation of complex, high‐resolution structures within seconds, with open channels (≈50 µm). GelMA‐pNIPAM hydrogels show better cell compatibility compared to silkMA‐pNIPAM hydrogels, promoting cell adhesion and viability. This study demonstrates the thermosensitive hydrogels' capability to engineer intricate, high‐resolution tubular structures with volumetric printing–an efficient route to fabricate microenvironments mimicking native tissues with potential for developing relevant in vitro models. [ABSTRACT FROM AUTHOR]

Dysregulation of Abelson interactor 1 (ABI1) is associated with various states of disease including developmental defects, pathogen infections, and cancer. ABI1 is an adaptor protein predominantly known to regulate actin cytoskeleton organization processes such as those involved in cell adhesion, migration, and shape determination. Linked to cytoskeleton via vasodilator-stimulated phosphoprotein (VASP), Wiskott-Aldrich syndrome protein family (WAVE), and neural-Wiskott-Aldrich syndrome protein (N-WASP)-associated protein complexes, ABI1 coordinates regulation of various cytoplasmic protein signaling complexes dysregulated in disease states. The roles of ABI1 beyond actin cytoskeleton regulation are much less understood. This comprehensive, protein-centric review describes molecular roles of ABI1 as an adaptor molecule in the context of its dysregulation and associated disease outcomes to better understand disease state-specific protein signaling and affected interconnected biological processes. [ABSTRACT FROM AUTHOR]

In textbook illustrations of migrating cells, actomyosin contractility is typically depicted as the contraction force necessary for cell body retraction. This dogma has been transformed by the molecular clutch model, which acknowledges that actomyosin traction forces also generate and transmit biomechanical signals at the leading edge, enabling cells to sense and shape their migratory path in mechanically complex environments. To fulfill these complementary functions, the actomyosin system assembles a gradient of contractile energy along the front‐rear axis of migratory cells. Here, we highlight the hierarchic assembly and self‐regulatory network structure of the actomyosin system and explain how the kinetics of different nonmuscle myosin II (NM II) paralogs synergize during contractile force generation. Our aim is to emphasize how protrusion formation, cell adhesion, contraction, and retraction are spatiotemporally integrated during different modes of migration, including chemotaxis and durotaxis. Finally, we hypothesize how different NM II paralogs might tune aspects of migration in vivo, highlighting future research directions. [ABSTRACT FROM AUTHOR]

Cadherins are calcium dependent adhesion proteins that establish and maintain the intercellular mechanical contact by bridging the gap between adjacent cells. Desmoglein-2 (Dsg2) and desmocollin-2 (Dsc2) are tissue specific cadherin isoforms of the cell-cell contact in cardiac desmosomes. Mutations in the DSG2 -gene and in the DSC2 -gene are related to arrhythmogenic right ventricular cardiomyopathy (ARVC) a rare but severe heart muscle disease. Here, several possible homophilic and heterophilic binding interactions of wild-type Dsg2, wild-type Dsc2, as well as one Dsg2- and two Dsc2-variants, each associated with ARVC, are investigated. Using single molecule force spectroscopy (SMFS) with atomic force microscopy (AFM) and applying Jarzynski's equality the kinetics and thermodynamics of Dsg2/Dsc2 interaction can be determined. The free energy landscape of Dsg2/Dsc2 dimerization exposes a high activation energy barrier, which is in line with the proposed strand-swapping binding motif. Although the binding motif is not affected by any of the mutations, the binding kinetics of the interactions differ significantly from the wild-type. While wild-type cadherins exhibit an average complex lifetime of approx. 0.3 s interactions involving a variant consistently show - lifetimes that are substantially larger. The lifetimes of the wild-type interactions give rise to the picture of a dynamic adhesion interface consisting of continuously dissociating and (re)associating molecular bonds, while the delayed binding kinetics of interactions involving an ARVC-associated variant might be part of the pathogenesis. Our data provide a comprehensive and consistent thermodynamic and kinetic description of cardiac cadherin binding, allowing detailed insight into the molecular mechanisms of cell adhesion. [Display omitted] • Integrity of heart muscle tissue relies on weak molecular bonds between cadherins. • Single molecule force spectroscopy reveals cadherin binding kinetics. • Wild-type cadherin bonds exhibit characteristic fast (re-) binding kinetics. • Specific cardiomyopathy associated cadherin variants slow binding kinetics. • Impaired molecular dynamics could be a cardiomyopathy-specific pathomechanism. [ABSTRACT FROM AUTHOR]

The p21‐activated kinase (PAK) family of proteins regulates various processes requiring dynamic cytoskeleton organization such as cell adhesion, migration, proliferation, and apoptosis. Among the six members of the protein family, PAK2 is specifically involved in apoptosis, angiogenesis, or the development of endothelial cells. We report a novel de novo heterozygous missense PAK2 variant, p.(Thr406Met), found in a newborn with clinical manifestations of Knobloch syndrome. In vitro experiments indicated that this and another reported variant, p.(Asp425Asn), result in substantially impaired protein kinase activity. Similar findings were described previously for the PAK2 p.(Glu435Lys) variant found in two siblings with proposed Knobloch syndrome type 2 (KNO2). These new variants support the association of PAK2 kinase deficiency with a second, autosomal dominant form of Knobloch syndrome: KNO2. [ABSTRACT FROM AUTHOR]

The impact of RHBDF2 on the expression and potential function in many cancers is still unknown. Therefore, the expression and methylation modification of RHBDF2 were evaluated across TCGA cancers in this study. Moreover, two methods, COX regression and Kaplan-Meier, were utilized for analyses of the prognoses of RHBDF2 in patients. Besides, the association between RHBDF2 and immune microenvironment, mutation, tumor mutation burden and microsatellite instability was analyzed with Pearson correlation. We verified RHBDF2 expression in hepatocellular carcinoma (HCC) compared with normal cell and tissue samples, detected the effects of RHBDF2 knockdown on biological functions in HCC cells, and detected CD4, CD8 and CD68 expression in hepatocellular carcinoma tissues and paired normal tissues. Given these results, the significant mRNA overexpression and promoter hypomethylation of RHBDF2 in various tumor types was showed, and a clear relationship between RHBDF2 overexpression and unfavourable overall survival and progression-free survival was observed, including liver hepatocellular carcinoma (LIHC), glioma (GBMLGG) and pancreatic adenocarcinoma (PAAD). Additionally, hypomethylation of RHBDF2 can affect the overall survival in some tumors. Furthermore, a clear correlation between RHBDF2 and infiltration of immune cells, immune-related molecules, TMB and MSI was observed. Besides, RHBDF2 expression is upregulated in HCC cells and tissues, and RHBDF2 knockdown could decrease the cell adhesion ability of HCC cells. More importantly, the expression of CD4, CD8 and CD68 was higher in HCC tissues. Altogether, the research denoted that RHBDF2 can be a prognostic biomarker for cancers according to these results and participate in cell adhesion of HCC cells. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the leading neurodegenerative pathology in aged individuals, but many questions remain on its pathogenesis, and a cure is still not available. Recent research efforts have generated measurements of multiple omics in individuals that were healthy or diagnosed with AD. Although machine learning approaches are well-suited to handle the complexity of omics data, the models typically lack interpretability. Additionally, while the genetic landscape of AD is somewhat more established, the proteomic landscape of the diseased brain is less well-understood. Here, we establish a deep learning method that takes advantage of an ensemble of autoencoders (AEs) -- EnsembleOmicsAE-to reduce the complexity of proteomics data into a reduced space containing a small number of latent features. We combine brain proteomic data from 559 individuals across three AD cohorts and demonstrate that the ensemble autoencoder models generate stable latent features which are well-suited for downstream biological interpretation. We present an algorithm to calculate feature importance scores based on the iterative scrambling of individual input features (i.e., proteins) and show that the algorithm identifies signaling modules (AE signaling modules) that are significantly enriched in protein-protein interactions. The molecular drivers of AD identified within the AE signaling modules derived with EnsembleOmicsAE were missed by linear methods, including integrin signaling and cell adhesion. Finally, we characterize the relationship between the AE signaling modules and the age of death of the patients and identify a differential regulation of vimentin and MAPK signaling in younger compared with older AD patients. [ABSTRACT FROM AUTHOR]

Background: Decellularized extracellular matrix (dECM) has been proposed as a useful source of biomimetic materials for regenerative medicine due to its biological properties that regulate cell behaviors. The present study aimed to investigate the influence of decellularized ECM derived from dental pulp stem cells (DPSCs) on gingival fibroblast (GF) cell behaviors. Cells were isolated from dental pulp and gingival tissues. ECM was derived from culturing dental pulp stem cells in growth medium supplemented with ascorbic acid. A bioinformatic database of the extracellular matrix was constructed using Metascape. GFs were reseeded onto dECM, and their adhesion, spreading, and organization were subsequently observed. The migration ability of the cells was determined using a scratch assay. Protein expression was evaluated using immunofluorescence staining. Results: Type 1 collagen and fibronectin were detected on the ECM and dECM derived from DPSCs. Negative phalloidin and nuclei were noted in the dECM. The proteomic database revealed enrichment of several proteins involved in ECM organization, ECM–receptor interaction, and focal adhesion. Compared with those on the controls, the GFs on the dECM exhibited more organized stress fibers. Furthermore, cultured GFs on dECM exhibited significantly enhanced migration and proliferation abilities. Interestingly, GFs seeded on dECM showed upregulation of FN1, ITGB3, and CTNNB1 mRNA levels. Conclusions: ECM derived from DSPCs generates a crucial microenvironment for regulating GF adhesion, migration and proliferation. Therefore, decellularized ECM from DPSCs could serve as a matrix for oral tissue repair. [ABSTRACT FROM AUTHOR]

Introduction Studies addressing the methylation pattern in adamantinomatous craniopharyngioma (ACP) are lacking. Objective To identify methylation signatures in ACPs regarding clinical presentation and outcome. Methods Clinical and pathology data were collected from 35 patients with ACP (54% male; 18.1 years [2-68]). CTNNB1 mutations and methylation profile (MethylationEPIC/Array-Illumina) were analyzed in tumoral DNA. Unsupervised machine learning analysis of this comprehensive methylome sample was achieved using hierarchical clustering and multidimensional scaling. Statistical associations between clusters and clinical features were achieved using the Fisher test and global biological process interpretations were aided by Gene Ontology enrichment analyses. Results Two clusters were revealed consistently by all unsupervised methods (ACP-1: n = 18; ACP-2: n = 17) with strong bootstrap statistical support. ACP-2 was enriched by CTNNB1 mutations (100% vs 56%, P =.0006), hypomethylated in CpG island, non-CpG Island sites, and globally (P <.001), and associated with greater tumor size (24.1 vs 9.5 cm3, P =.04). Enrichment analysis highlighted pathways on signaling transduction, transmembrane receptor, development of anatomical structures, cell adhesion, cytoskeleton organization, and cytokine binding, and cell type-specific biological processes as regulation of oligodendrocytes, keratinocyte, and epithelial cells differentiation. Conclusion Two clusters of patients with ACP were consistently revealed by unsupervised machine learning methods, with one of them significantly hypomethylated, enriched by CTNNB1 mutated ACPs, and associated with increased tumor size. Enrichment analysis reinforced pathways involved in tumor proliferation and in cell-specific tumoral microenvironment. [ABSTRACT FROM AUTHOR]

Gliomas are malignant tumors of neuronal support cells within the central nervous system (CNS) and are characterized by poor overall prognoses and limited treatment options due to their infiltrative growth patterns. The neural tumor microenvironment, composed of benign neurons, neuroglia, endothelial cells, and intravascular white blood cells, is a target-rich site for potential chemotherapeutic agents. This study assessed cell proliferation rates, white blood cell components, and a limited number of nuclear, cytoplasmic, and membrane markers using immunohistochemistry (IHC) assays on formalin-fixed and paraffin-embedded benign and glial tumor tissue samples from the CNS. It was observed that glioma tissues had increased rates of glial cell proliferation and significant increases in the number of observed T-lymphocytes and granulocytes but decreased expression of markers Somatostatin receptor 2 (SSTR2), L1 cell adhesion molecule (L1CAM), and GATA binding protein 3 (GATA3) when compared to benign tissue samples. Understanding the lack of protein expression and population expansion potential of the glioma microenvironment in greater detail could help identify valuable therapeutic target combinations for future treatments. [ABSTRACT FROM AUTHOR]

Pathological observations show that cancer cells frequently invade the surrounding normal tissue in collective rather than individual cell migration. However, general principles governing collective cell migration remain to be discovered. Different from individual cell migration, we demonstrated that the Notch‐1‐activation reduced collective cells speed and distances. In particular, Notch‐1‐activation induced cellular cytoskeletal remodelling, strengthened the intercellular junctions and cell‐matrix adhesions. Mechanistically, Notch‐1 activation prevented the phosphorylation of GSK‐3β and the translocation of cytoplasmic free β‐catenin to the nucleus, which increased E‐cadherin expression and tight intercellular junctions. Moreover, Notch‐1 signalling also activated the RhoA/ROCK pathway, promoting reorganization of F‐actin and contractile forces produced by myosin. Further, Notch‐1 activation increased cell adhesion to the extracellular substrate, which inhibited collective cell migration. These findings highlight that cell adhesions and cell–cell junctions contribute to collective cell migration and provide new insights into mechanisms of the modulation of Notch‐1 signalling pathway on cancer cell malignancy. [ABSTRACT FROM AUTHOR]

To further understand the impact of deficiency of the autoimmune regulator (Aire) gene during the adhesion of medullary thymic epithelial cells (mTECs) to thymocytes, we sequenced single-cell libraries (scRNA-seq) obtained from Aire wild-type (WT) (Airewt/wt) or Aire-deficient (Airewt/mut) mTECs cocultured with WT single-positive (SP) CD4+ thymocytes. Although the libraries differed in their mRNA and long noncoding RNA (lncRNA) profiles, indicating that mTECs were heterogeneous in terms of their transcriptome, UMAP clustering revealed that both mTEC lines expressed their specific markers, i.e., Epcam, Itgb4, Itga6, and Casp3 in resting mTECs and Ccna2, Pbk, and Birc5 in proliferative mTECs. Both cocultured SP CD4+ thymocytes remained in a homogeneous cluster expressing the Il7r and Ccr7markers. Comparisons of the two types of cocultures revealed the differential expression of mRNAs that encode transcription factors (Zfpm2, Satb1, and Lef1), cell adhesion genes (Itgb1) inmTECs, and Themis in thymocytes, which is associated with the regulation of positive and negative selection. At the single-cell sequencing resolution, we observed that Aire acts on both Aire WT and Airedeficient mTECs as an upstream controller of mRNAs, which encode transcription factors or adhesion proteins that, in turn, are posttranscriptionally controlled by lncRNAs, for example, Neat1, Malat1, Pvt1, and Dancr among others. Under Aire deficiency, mTECs dysregulate the expression of MHC-II, CD80, and CD326 (EPCAM) protein markers as well as metabolism and cell cycle-related mRNAs, which delay the cell cycle progression. Moreover, when adhered to mTECs, WT SP CD4+ or CD8+ thymocytes modulate the expression of cell activation proteins, including CD28 and CD152/CTLA4, and the expression of cellular metabolism mRNAs. These findings indicate a complex mechanism through which an imbalance in Aire expression can affect mTECs and thymocytes during adhesion. [ABSTRACT FROM AUTHOR]

The creation of functional hydrogels with robust load‐bearing capacity adaptable to complex tissue regeneration remains challenging. Silk fibroin (SF) is a natural biomaterial with excellent mechanical strength and cell adhesion capacity, possessing tremendous potential to solve the aforementioned dilemma. The excellent biodegradability and biocompatibility and the molecular structure with multiple modifiable moieties provide opportunities for the injectability and multifunctionality of hydrogels. Furthermore, the incorporation of other polymers or active ingredients can improve the basic properties, confer biological activities and pharmacological effects, and provide the prerequisites for hydrogels to fulfill specific requirements. Therefore, SF‐based hydrogels are widely applied in tissue repair and regeneration, especially in bone, skin, nerve, liver, myocardium, and cornea, which have effectively addressed the challenges of scaffolds' lack of cell adhesion sites, excessive degradation, as well as the lack of efficient, long‐lasting antimicrobial properties. This review outlines the properties of SF, discusses the types of materials commonly used in the preparation of hydrogels and their characteristics, and describes the current construction methods of SF hydrogels. Simultaneously, recent advancements in applying SF‐based multifunctional hydrogels within biological tissues are explored, with a focus on their role in tissue repair, highlighting the repair mechanism of SF based on bone and skin. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of a drug‐coated balloon (DCB) on inflammatory cytokines in patients with coronary artery calcification (CAC) after interventional therapy. Methods: This study included 58 patients with coronary heart disease who underwent coronary angiography (CAG) from October 2020 to September 2021. Patients were divided into CAC and non‐CAC groups, and a DCB was used to intervene in the target lesions. Ten‐milliliter preoperative and postoperative blood samples were drawn from the coronary lesions in both groups to detect the expression of serum interleukin‐6 (IL‐6), tumor necrosis factor‐alpha (TNF‐α), and intercellular adhesion molecule‐1 (ICAM‐1). All patients were subjected to a 6‐month follow‐up to observe the incidence of major adverse cardiac events (MACEs). Results: No significant differences in baseline clinical data were found between the groups. Serum IL‐6, TNF‐α, and ICAM‐1 expressions in coronary blood samples immediately before DCB were not significantly different from those after DCB in all patients. After DCB, serum TNF‐α expression in the CAC group was significantly lower than that in the non‐CAC group (p < 0.05). In contrast, no significant difference in serum IL‐6 and ICAM‐1 expression was found between the groups. During the 6‐month follow‐up, no significant difference in the incidence of MACE was found between both groups. Conclusions: DCB reduced the expression of inflammatory cytokine TNF‐α in CAC, which may be one of the key mechanisms underlying the treatment of CAC by DCB. [ABSTRACT FROM AUTHOR]

This investigation evaluated the therapeutic benefit of apocynin in isoproterenol (ISO)‐induced cardiac damage in rats. ISO‐administered male Wistar rats were treated with apocynin for 2 weeks. Blood plasma and left ventricle of heart tissues were collected and analyzed for oxidative stress‐related parameters such as malondialdehyde (MDA), advanced oxidation protein product (AOPP), and nitric oxide (NO). The activities of endogenous antioxidant enzymes such as superoxide dismutase (SOD) and catalase were also measured. The gene expressions of oxidative stress‐related proteins such as Nrf‐2, HO‐1, and HO‐2 in cardiac tissues were also measured. In silico studies like molecular docking and molecular dynamics were also performed to detect how apocynin interacts with NADPH and nitric oxide synthase at the molecular level. This investigation revealed significant elevation of serum transferase enzymes and creatinine kinase‐Muscle Brain (CK‐MB) activities in ISO‐administered rats compared to the control. Apocynin effectively normalized the serum transferases and CK‐MB activities in the blood of ISO‐stressed rats. Moreover, ISO‐induced elevations of MDA, NO, and AOPP levels were also suppressed by apocynin treatment. Consistently, apocynin restored the reduced SOD and catalase activities in ISO‐administered rats. This restoration of enzyme activity might be due to the increased expression of Nrf‐2 and HO‐1 and reduced expression of iNOS and TNF‐α in ISO‐administered rats. Histological analysis revealed that apocynin treatment ameliorated the mononuclear cell adherence and fibrosis in the cardiac tissue of ISO‐administered rats. Computational studies also support the experimental findings. This study demonstrates that apocynin prevents ISO‐induced cardiac injury not only by preventing inflammation but also by empowering the antioxidant defense system. [ABSTRACT FROM AUTHOR]

ABSTRACT How tissues develop distinct structures remains poorly understood. We propose herein the Lego hypothesis of tissue morphogenesis, which states that during tissue morphogenesis, the topographical properties of cell surface adhesion molecules can be dynamically altered and polarised by regulating the spatiotemporal expression and localization of orientational cell adhesion (OCA) molecules cell‐autonomously and non‐cell‐autonomously, thus modulating cells into unique Lego pieces for self‐assembling into distinct cytoarchitectures. This concept can be exemplified by epithelial morphogenesis, in which cells are coalesced into a sheet by many types of adhesions. Among them, parallel OCAs (pOCAs) at the lateral cell membranes are essential for configuring cells in parallel. Major pOCAs include Na+/K+‐ATPase‐mediated adhesions, Crumbs‐mediated adhesions, tight junctions, adherens junctions, and desmosomes. These pOCAs align in stereotypical orders along the apical‐to‐basal axis, and their absolute positioning is also regulated. Such spatial organization of pOCAs underlies proper epithelial morphogenesis. Thus, a key open question about tissue morphogenesis is how to regulate OCAs to make compatible adhesive cellular Lego pieces for tissue construction. [ABSTRACT FROM AUTHOR]

Measurements of cell lineages are central to a variety of fundamental biological questions, ranging from developmental to cancer biology. However, accurate lineage tracing requires nearly perfect cell tracking, which can be challenging due to cell motion during imaging. Here we demonstrate the integration of microfabrication, imaging, and image processing approaches to demonstrate a platform for cell lineage tracing. We use quantitative phase imaging (QPI), a label-free imaging approach that quantifies cell mass. This gives an additional parameter, cell mass, that can be used to improve tracking accuracy. We confine lineages within microwells fabricated to reduce cell adhesion to sidewalls made of a low refractive index polymer. This also allows the microwells themselves to serve as references for QPI, enabling measurement of cell mass even in confluent microwells. We demonstrate application of this approach to immortalized adherent and nonadherent cell lines as well as stimulated primary B cells cultured ex vivo. Overall, our approach enables lineage tracking, or measurement of lineage mass, in a platform that can be customized to varied cell types. [ABSTRACT FROM AUTHOR]

Endothelial cells (ECs) line the inner walls of blood vessels, respond to shear stress by elongating in the direction of flow. Engineering aligned ECs in vitro is essential for modeling human vascular diseases and for drug testing. Current microfluidic approaches mainly rely on unidirectional laminar flow, uniform coating of surfaces to improve cellular adhesion or alteration of the surface topography. Challenges persist due to shear stress‐induced changes in cellular behavior, especially in complex multicellular environments and the time needed for the cells to align and polarize inside the microfluidic conduits. Generally, protein coating processes and physical treatments are also not compatible with the steps required for the assembly of microfluidic devices. This approach employs aerosol jet printing (AJP) to precisely pattern poly(3,4‐ethylenedioxythiophene) polystyrene sulphonate (PEDOT:PSS) within microfluidic chambers in a single step. It is shown that the PEDOT:PSS is biocompatible and facilitates EC adhesion, patterning, elongation, and alignment. Under capillary flow, the cells retain their pattern‐induced morphology over 7 d, confirming the efficacy of the approach in promoting cellular organization, eliminating the need for external pumps. Furthermore, it is demonstrated that the PEDOT:PSS pattern retains structural integrity and electrical stability following oxygen plasma treatment, required for assembling of fully enclosed microfluidic devices. [ABSTRACT FROM AUTHOR]

This study provides a detailed molecular mechanism of the layer‐by‐layer (LbL) film formation process involving BB polymers. The roles of adsorbed and non‐adsorbed chain segments during the layer buildup are revealed by employing surface force apparatus (SFA) and atomic force microscopy (AFM) to probe critical aspects such as surface coverage, polymer conformation at the surface, adhesive properties, and morphology after each layer deposition. The results show that the thickness, nanomechanical properties, and surface chemistry of the nanofilms are significantly influenced by the number of layers. All these cues have an important impact on cell behavior when employed as coatings for culture substrates. The evidence is shown that cells respond very differently to these cues and exhibit behavior that goes from superproliferation down to accelerated death. [ABSTRACT FROM AUTHOR]

Using bone regeneration scaffolds to repair craniomaxillofacial bone defects is a promising strategy. However, most bone regeneration scaffolds still exist some issues such as a lack of barrier structure, inability to precisely match bone defects, and necessity to incorporate biological components to enhance efficacy. Herein, inspired by a periosteum‐bone complex, a class of multifunctional hierarchical porous poly(lactic‐co‐glycolic acid)/baicalein scaffolds is facilely prepared by the union of personalized negative mold technique and phase separation strategy and demonstrated to precisely fit intricate bone defect cavity. The dense up‐surface of the scaffold can prevent soft tissue cell penetration, while the loose bottom‐surface can promote protein adsorption, cell adhesion, and cell infiltration. The interior macropores of the scaffold and the loaded baicalein can synergistically promote cell differentiation, angiogenesis, and osteogenesis. These findings can open an appealing avenue for the development of personalized multifunctional hierarchical materials for bone repair. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusions This study aimed to ascertain the serum levels of selectins (E, L, P) and platelet‐endothelial adhesion molecule‐1 (PECAM‐1) in preschool children with autism spectrum disorder (ASD) and to establish a comparison with the levels observed in healthy controls.The study included 34 children aged 2–7 years diagnosed with ASD (ASD group) and 34 randomly selected healthy children matched for age and sex to the ASD group. The children were free of any genetic or physical disease, clinically active infection, or medication use. The sociodemographic data form was completed by all parents. The Childhood Autism Rating Scale (CARS) and the Autism Behavior Checklist (ABC) were administered to the patient group, and the Aberrant Behavior Checklist (AbBC) was completed by the families of all children. Serum selectin (E, L, P) and PECAM‐1 levels were measured using enzyme‐linked immunosorbent assay (ELISA) kits.The results showed that the levels of both L‐selectin (p = 0.007) and PECAM‐1 (p = 0.019) were significantly lower in the ASD group than in the control group. No significant difference was observed between the groups concerning E‐selectin and P‐selectin levels (p > 0.05). It was observed that P‐selectin variables were statistically significant in predicting the presence of ASD (p = 0.019). A remarkable inverse correlation was found between the AbBC irritability subscale score and L‐selectin (r = −0.296, p = 0.014) and PECAM‐1 (r = −0.276, p = 0. 023); the AbBC Lethargy‐Social Withdrawal subscale score and E‐Selectin (r = −0.239, p = 0.049), L‐Selectin (r = −0.297, p = 0.014) and PECAM‐1 (r = −0.264, p = 0.029); L‐Selectin levels and the AbBC stereotypic behavior subscale (r = −0.248, p = 0.042). No statistically significant relationship was observed between selectins (E, L, P) and PECAM‐1 levels and CARS scale, ABC subscale or total scores and age variables (p > 0.05).These study results suggest that L‐selectin, P‐selectin and PECAM‐1 may play a role in the pathophysiology of ASD. [ABSTRACT FROM AUTHOR]

Ceramics is a promising material that has been widely used as artificial bones. However, most available investigations were devoted to new material development and implant structure design, while few of studies focused on innovative hybrid implants that can act not only as implants but also as surgery tools for solving specific health issues. This paper innovatively designed and additively-manufactured a zirconia ceramic surgery tool, which can not only act as a drilling tool, but also retain itself in the drilled hole after the surgery as bone scaffold, at the meantime delivery active ingredient (Vitamin C) for fast recovery. To achieve early intervention, the proposed zirconia ceramic tool was additively manufactured with inter-connected pore structures that can benefit the recovery. The zirconia ceramic surgery tools (with 50 %, 70 % and 80 % porosity) showed the required mechanical properties to act as a drilling tool. The tool also showed drug releasing function with the different diffusion rates based on drug diffusion experiments. The zirconia ceramic tool with Vitamin C coating also showed enhanced cell adhesion and accelerated cell growth based on the osteoblast induction assessment. Based on above, the proposed zirconia ceramic tool is expected to bring new possibilities for wide applications of ceramic tools in surgeries. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA), a commonly used material for bone repair, can enhance its biological properties through the modulation of its crystallinity. Exploring the variations in physicochemical and biological properties associated with different degrees of crystallinity is crucial for advancing the applications of HA. In this study, stoichiometric nano-apatite precursors were initially synthesized using chemical precipitation. Subsequently, four groups of HA ceramics with varying degrees of crystallinity (24 %, 42 %, 72 %, 100 %) were produced by adjusting the calcination temperature, as confirmed through comprehensive characterizations. A systematic investigation was then conducted to examine the impact of crystallinity on the physicochemical, cytological, and in vivo osteogenic properties of HA ceramics, elucidating the influence of crystallinity on the osteogenic potential of HA. Results indicated that higher crystallinity in HA ceramics enhanced mechanical strength and hardness while reducing surface roughness, hydrophilicity, and protein affinity. Cytological studies revealed that decreased crystallinity led to lower cell proliferation rates but facilitated cell adhesion, spreading, and increased expression of osteogenic genes. Moreover, cell experiments with extracts further supported the significant role of surface properties of HA ceramics in modulating cell behavior. In vivo osteogenic assays demonstrated that reduced crystallinity notably stimulated new bone formation. Overall, by integrating the results of in vitro and in vivo experiments, it can be concluded that reducing the crystallinity of HA ceramics, the biological properties of HA ceramics can be significantly enhanced while maintaining a certain level of mechanical strength, such as HA2 group (42 % crystallinity). This study highlights the substantial impact of crystallinity and surface characteristics of HA ceramics on cell behavior, offering valuable insights and strategies for enhancing and optimizing bone repair materials in future applications. [ABSTRACT FROM AUTHOR]

Percutaneous implants osseointegrated into the residuum of a person with limb amputation need to provide mechanical stability and protection against infections. Although significant progress has been made in the biointegration of percutaneous implants, the problem of forming a reliable natural barrier at the level of the surface of the implant and the skin and bone tissues remains unresolved. The use of a microporous implant structure incorporated into the Skin and Bone Integrated Pylon (SBIP) should address the issue by allowing soft and bone tissues to grow directly into the implant structure itself, which, in turn, should form a reliable barrier to infections and support strong osseointegration. To evaluate biological interactions between dermal fibroblasts and MC3T3-E1 osteoblasts in vitro, small titanium discs (with varying pore sizes and volume fractions to achieve deep porosity) were fabricated via 3D printing and sintering. The cell viability MTT assay demonstrated low cytotoxicity for cells co-cultured in the pores of the 3D-printed and sintered Ti samples during the 14-day follow-up period. A subsequent Quantitative Real-Time Polymerase Chain Reaction (RT-PCR) analysis of the relative gene expression of biomarkers that are associated with cell adhesion (α2, α5, αV, and β1 integrins) and extracellular matrix components (fibronectin, vitronectin, type I collagen) demonstrated that micropore sizes ranging from 200 to 500 µm of the 3D printed and sintered Ti discs were favorable for dermal fibroblast adhesion. For example, for representative 3D-printed Ti sample S6 at 72 h the values were 4.71 ± 0.08 (α2 integrin), 4.96 ± 0.08 (α5 integrin), 4.71 ± 0.08 (αV integrin), and 1.87 ± 0.12 (β1 integrin). In contrast, Ti discs with pore sizes ranging from 400 to 800 µm demonstrated the best results (in terms of marker expression related to osteogenic differentiation, including osteopontin, osteonectin, osteocalcin, TGF-β1, and SMAD4) for MC3T3-E1 cells. For example, for the representative 3D sample S4 on day 14, the marker levels were 11.19 ± 0.77 (osteopontin), 7.15 ± 0.29 (osteonectin), and 6.08 ± 0.12 (osteocalcin), while for sintered samples the levels of markers constituted 5.85 ± 0.4 (osteopontin), 4.45 ± 0.36 (osteonectin), and 4.46 ± 0.3 (osteocalcin). In conclusion, the data obtained show the high biointegrative properties of porous titanium structures, while the ability to implement several pore options in one structure using 3D printing makes it possible to create personalized implants for the best one-time integration with both skin and bone tissues. [ABSTRACT FROM AUTHOR]

Metals play a crucial role in the human body, especially as ions in metalloproteins. Essential metals, such as calcium, iron, and zinc are crucial for various physiological functions, but their interactions within biological networks are complex and not fully understood. Mesenchymal stem/stromal cells (MSCs) are essential for tissue regeneration due to their ability to differentiate into various cell types. This review article addresses the effects of physiological and unphysiological, but not directly toxic, metal ion concentrations, particularly concerning MSCs. Overloading or unbalancing of metal ion concentrations can significantly impair the function and differentiation capacity of MSCs. In addition, excessive or unbalanced metal ion concentrations can lead to oxidative stress, which can affect viability or inflammation. Data on the effects of metal ions on MSC differentiation are limited and often contradictory. Future research should, therefore, aim to clarify the mechanisms by which metal ions affect MSC differentiation, focusing on aspects such as metal ion interactions, ion concentrations, exposure duration, and other environmental conditions. Understanding these interactions could ultimately improve the design of biomaterials and implants to promote MSC-mediated tissue regeneration. It could also lead to the development of innovative therapeutic strategies in regenerative medicine. [ABSTRACT FROM AUTHOR]

Ageing and fertility are intertwined. Germline loss extends the lifespan in various organisms, termed gonadal longevity. However, the original longevity signal from the somatic gonad remains poorly understood. Here, we focused on the interaction between germline stem cells (GSCs) and their niche, the distal tip cells (DTCs), to explore the barely known longevity signal from the somatic gonad in C. elegans. We found that removing germline disrupts the cell adhesions between GSC and DTC, causing a significant transcriptomic change in DTC through hmp-2 /β-catenin and two GATA transcription factors, elt-3 and pqm-1 in this niche cell. Inhibiting elt-3 and pqm-1 in DTC suppresses gonadal longevity. Moreover, we further identified the TGF-β ligand, tig-2, as the cytokine from DTC upon the loss of germline, which evokes the downstream gonadal longevity signalling throughout the body. Our findings thus reveal the source of the longevity signalling in response to germline removal, highlighting the stem cell niche as a critical signalling hub in ageing. Synopsis: How loss of the germline increases longevity in C. elegans has remained unknown. This study shows that germline ablation is sensed by adhesion disruption between germline stem cells (GSCs) and gonadal niche cells, altering stromal expression patterns and cytokine secretion for enhanced longevity signalling in distal tissues. Depletion of GSCs disrupts the cell adhesion with their niche, distal tip cells (DTCs), leading to transcriptome changes and enhanced longevity of worms. Translocation of HMP-2/β-catenin, and the GATA transcription factors, ELT-3 and PQM-1, are required for DTC-mediated longevity induction upon germline loss. TGF-β ligand TIG-2 is upregulated and secreted by DTCs upon germline loss, activating systemic longevity signalling pathways. Defective germline stem cell maintenance disrupts niche cell adhesion, altering transcription factor expression and growth factor secretion for increased longevity in the worm. [ABSTRACT FROM AUTHOR]