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This document is a correction notice for an article titled "Hyaluronic Acid/Collagen Nanofiber Tubular Scaffolds Support Endothelial Cell Proliferation, Phenotypic Shape and Endothelialization" published in the journal Nanomaterials. The correction addresses errors in Figures 1B, 2A, and 5A of the original publication. The corrected figures are provided in the document. The authors apologize for any inconvenience caused but state that the scientific conclusions of the article remain unaffected. [Extracted from the article]

Single- or few-layer forms of black phosphorus, so called phosphorene, were isolated by exfoliation in 2014 as 2D layered materials holding great promise in electronic and optoelectronic fields. In this perspective, we highlight recent developments in black phosphorus research, in particular, we will focus on the mechanical properties of its 2D form. Its unique puckered structure is responsible for strong anisotropy in mechanical and transport properties, different from graphene and transition-metal dichalcogenide 2D materials. This peculiar mechanical anisotropy can be exploited for applications such as nanomechanical resonators, thermoelectric devices, and motion sensors with tunable functions inaccessible by isotropic materials. Current bottlenecks hindering further progress in devices applications involve first surface degradation in environmental conditions which, in turn, can be exploited in surface friction mechanics to achieve superlubricity. In this framework, the investigation of mechanical properties of phosphorene will be pivotal for facile fabrication, transfer, and resolution of technical hurdles as well the discovery of novel applications. As research directions in next foreseeable future, we will discuss the challenge of crosstalk between mechanical and transport properties, in particular, how the stress–strain stimulations can be used to tune optoelectronic and thermoelectric performance. [ABSTRACT FROM AUTHOR]

Air pollution is known as one of the most important causes of death in the whole world. Therefore, pollution reduction to achieve clean air was noticed by everyone. This way, using nanotechnology to control air and monitor is a novel approach. This paper investigates the effect of the number of graphene nano-pores on the SiO 2 separation from the H 2 O vapour in the presence of an external electric field with the magnitude of 0.01 V/Å using the molecular dynamics (MD) method. The electric field affects the charged particles and causes disturbance in the structure. It also prevents SiO 2 nanoparticles from passing through the graphene nanosheet. Also, the presence of carbon nanosheets acts as a membrane and affects the diffusion of water in the nanostructure. So, the results show that in the presence of a nano-pore, the number of H 2 O molecules reaches to 496 and 568 in reservoirs 2 and 3. Also, the number of SiO 2 nanoparticles reaches 10 and 4 in reservoirs 2 and 3. This shows that in reservoirs 2 and 3, about 80% and 60% of the SiO 2 nanoparticles are separated. As mentioned before, the electric field prevents the passage of SiO 2 nanoparticles through the graphene nanosheet. As the number of graphene nano-pores increases by 2, 3, 4, and 5, the number of passing water molecules increases. Considering that the number of graphene nano-pores has increased and the movement path of particles has increased, the number of passing particles almost increases. However, the electric field prevents the passage of SiO 2 nanoparticles. According to the results, the suggested setup can be employed for designing highly efficient nanostructured membranes for air purification and monitoring. [Display omitted] [ABSTRACT FROM AUTHOR]

This study was designed to investigate the regulatory effect of hyaluronic acid (HA)—coating silk fibroin (SF) nanofibers during epithelialization of urinary tract for urethral regeneration. The obtained electrospun biomimetic tubular HA‐SF nanofiber scaffold is composed of a dense inner layer and a porous outer layer in order to mimic adhesion and cavernous layers of the native tissue, respectively. A thin layer of HA‐gel coating was fixed in the inner wall to provide SF nanofibers with a dense and smooth surface nano‐topography and higher hydrophilicity. Compared with pure SF nanofibers, HA‐SF nanofibers significantly promoted the adhesion, growth, and proliferation of primary urothelial cells, and up‐regulate the expression of uroplakin‐3 (terminal differentiation keratin protein in urothelium). Using the New Zealand male rabbit urethral injury model, the scaffold composed of tubular HA‐SF nanofibers could recruit lumen and myoepithelial cells from the adjacent area of the host, rapidly reconstructing the urothelial barrier in the wound area in order to keep the urinary tract unobstructed, thereby promoting luminal epithelialization, smooth muscle bundle structural remodeling, and capillary formation. Overall, the synergistic effects of nano‐topography and biophysical cues in a biomimetic scaffold design for effective endogenous regeneration. [ABSTRACT FROM AUTHOR]

One of the main challenges of tissue-engineered vascular prostheses is restenosis due to intimal hyperplasia. The aim of this study is to develop a material for scaffolds able to support cell growth while tolerating physiological conditions and maintaining the patency of carotid artery model. Tubular hyaluronic acid (HA)-functionalized collagen nanofibrous composite scaffolds were prepared by sequential electrospinning method. The tubular composite scaffold has well-controlled biophysical and biochemical signals, providing a good matrix for the adhesion and proliferation of vascular endothelial cells (ECs), but resisting to platelets adhesion when exposed to blood. Carotid artery replacement experiment from 6-week rabbits showed that the HA/collagen nanofibrous composite scaffold grafts with endothelialization on the luminal surface could maintain vascular patency. At retrieval, the composite scaffold maintained good structural integrity and had comparable mechanical strength as the native artery. This study indicating that electrospun scaffolds combined with cells may become an alternative to prosthetic grafts for vascular reconstruction. [ABSTRACT FROM AUTHOR]

Artificial intelligent actuators are extensively explored for emerging applications such as soft robots, human‐machine interfaces, and biomedical devices. However, intelligent actuating systems based on synthesized polymers suffer from challenges in renewability, sustainability, and safety, while natural polymer‐based actuators show limited capabilities and performances due to the presence of abundant hydrogen‐bond lockers. Here this study reports a new hydrogen bond‐mediated strategy to develop mimosa‐inspired starch actuators (SA). By harnessing the unique features of gelatinization and abundant hydrogen bonds, these SA enable high‐sensitivity and multi‐responsive actuation in various scenarios. The non‐gelatinized SA can be irreversibly programmed into diverse shapes, such as artificial flowers, bowl shapes, and helix structures, using near‐infrared light. Furthermore, the gelatinized SA exhibit reversibly multi‐responsive actuation when exposed to low humidity (10.2%), low temperature (37 °C), or low‐energy light (0.42 W cm−2). More importantly, the SA demonstrate robust applications in smart living, including artificial mimosa, intelligent lampshade, and morphing food. By overcoming the hydrogen‐bond lockers inherent in natural polymers, SA open new avenues for next‐generation recyclable materials and actuators, bringing them closer to practical applications. [ABSTRACT FROM AUTHOR]

Atomic Force Microscopy (AFM) has a great potential as a tool to characterize mechanical and morphological properties of living cells; these properties have been shown to correlate with cells' fate and patho-physiological state in view of the development of novel early-diagnostic strategies. Although several reports have described experimental and technical approaches for the characterization of cellular elasticity by means of AFM, a robust and commonly accepted methodology is still lacking. Here, we show that micrometric spherical probes (also known as colloidal probes) are well suited for performing a combined topographic and mechanical analysis of living cells, with spatial resolution suitable for a complete and accurate mapping of cell morphological and elastic properties, and superior reliability and accuracy in the mechanical measurements with respect to conventional and widely used sharp AFM tips. We address a number of issues concerning the nanomechanical analysis, including the applicability of contact mechanical models and the impact of a constrained contact geometry on the measured Young's modulus (the finite-thickness effect). We have tested our protocol by imaging living PC12 and MDA-MB-231 cells, in order to demonstrate the importance of the correction of the finite-thickness effect and the change in Young's modulus induced by the action of a cytoskeleton-targeting drug. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication of a planar supercapacitor based on cluster-assembled nanostructured carbon (ns-C) thin films deposited by supersonic cluster beam deposition and ionic liquid as electrolyte has been demonstrated. Cluster-assembled carbon has a density of about 0.5g/cm3 and a highly disordered structure with predominant sp2 hybridization, high surface roughness and granular nanoscale morphology. The electric double layer capacity of ns-C films (thickness variable in the range of 140–500nm) was investigated by electrochemical impedance spectroscopy and cyclic voltammetry employing four different hydrophobic room-temperature ionic liquids featuring the same anion and with different cations as electrolyte. Evidence of good impregnation of the ns-C nanoporous matrix by the different ionic liquids was found. The highest EDL capacity, 75F/g, was obtained by using [Bmim][NTf2], the ionic liquid with the shortest alkyl chain. Using [Bmim][NTf2] a supercapacitor with single electrode area of 0.2cm2 and specific capacity of ∼80μF/cm2 was obtained. [Copyright &y& Elsevier]

To test the biocompatiblecharacter of room-temperature ionic liquids(ILs), the interaction of various ILs with biological membrane (biomembrane)models was studied in this work. Dioleoyl phosphatidylcholine (DOPC)adsorbed on a mercury (Hg) electrode forms an impermeable defect-freemonolayer which is a well established biomembrane model, prone tobe studied by electrochemical techniques. We have monitored the modificationsof the Hg supported monolayer caused by ILs using rapid cyclic voltammetry(RCV), alternating current voltammetry (ACV), and electrochemicalimpedance spectroscopy (EIS). A series of imidazolium-based ILs wereinvestigated whose interaction highlighted the role of anion and lateralside chain of cation during the interaction with DOPC monolayers.It was shown that the hydrophobic and lipophilic character of theIL cations is a primary factor responsible for this interaction. Hg-supportedmonolayers provide an accurate analysis of the behavior of ILs atthe interface of a biomembrane leading to a comprehensive understandingof the interaction mechanisms involved. At the same time, these experimentsshow that the Hg-phospholipid model is an effective toxicity sensingtechnique as shown by the correlation between literature in vivo toxicitydata and the data from this study. [ABSTRACT FROM AUTHOR]

In this study, we designed and synthetized artificial vascular scaffolds based on nanofibers of collagen functionalized with hyaluronic acid (HA) in order to direct the phenotypic shape, proliferation, and complete endothelization of mouse primary aortic endothelial cells (PAECs). Layered tubular HA/collagen nanofibers were prepared using electrospinning and crosslinking process. The obtained scaffold is composed of a thin inner layer and a thick outer layer that structurally mimic the layer the intima and media layers of the native blood vessels, respectively. Compared with the pure tubular collagen nanofibers, the surface of HA functionalized collagen nanofibers has higher anisotropic wettability and mechanical flexibility. HA/collagen nanofibers can significantly promote the elongation, proliferation and phenotypic shape expression of PAECs. In vitro co-culture of mouse PAECs and their corresponding smooth muscle cells (SMCs) showed that the luminal endothelialization governs the biophysical integrity of the newly formed extracellular matrix (e.g., collagen and elastin fibers) and structural remodeling of SMCs. Furthermore, in vitro hemocompatibility assays indicated that HA/collagen nanofibers have no detectable degree of hemolysis and coagulation, suggesting their promise as engineered vascular implants. [ABSTRACT FROM AUTHOR]

Microorganisms present on cotton fabric (CF) significantly affect its wearing comfort and pose potential threats to human health. This is mainly attributed to the porous and hygroscopic nature of CF, which easily adsorbs proteins, oily substances, and mineral salts, creating a favorable environment for microorganism proliferations. The bacteria firmly adhered to CF are difficult to remove by conventional washing, resulting in persistent stains. Furthermore, the mechanisms underlying bacterial interaction with fibers and bacterial inactivation remain to be fully understood. Herein, we synthetized reactive Gemini quaternary ammonium salt (CGQ) and sulfopropylbetaine (CGB) to covalently bind onto CF, thereby engineering a customized antimicrobial and antifouling CF while preserving its physicochemical properties. Real-time monitoring of the bacterial inactivation process was also performed. The antimicrobial efficacy of CF finished with CGQ and CGQ/CGB, employing only 5.0 mg/mL antimicrobial concentration, surpassed 95 % against Escherichia coli and 99 % against Staphylococcus aureus after 50 washes. The loosely adhered bacteria on CGQ/CGB-finished CF can be easily eliminated through conventional washing, resulting in an enduring antimicrobial and antifouling surface. Consequently, we have developed a straightforward strategy for the large-scale production of superior antimicrobial and antifouling CF, presenting a versatile solution with wide applications. Additionally, this method offers an efficient strategy for real-time monitoring of the microorganism inactivation process. Real-time monitoring of bacterial inactivating process of durable bactericidal and antifouling cotton fabric that was constructed based on Gemini quaternary ammonium salt and sulfopropylbetaine without compromising its physicochemical properties. [Display omitted] • Two reacting Gemini antimicrobials were successfully synthesized. • Long-term bactericidal and antifouling cotton fabric were fabricated. • The bacterial inactivating process was real-time monitored. • Antimicrobial finishing has no obvious effect on its comfort and biocompatibility. • Their antimicrobial and antifouling properties can be tailored facilely. [ABSTRACT FROM AUTHOR]

The specific binding of fluorescent probes or biomolecules to the actin cytoskeleton network is increasingly important for monitoring various complex cellular activities such as cell adhesion, proliferation, locomotion, endocytosis, and cell division. However, improving cell uptake and subcellular resolution is still the main obstacle for successful and wide application of cellular fluorescent probes. Here, we designed and synthesized an amphiphilic block polyurethane with peculiar photophysical properties of aggregation induced emission (AIE), which can be used in living cell imaging to promote selective visualization of cell structures. The AIE effect polyurethane (abbreviated as AIE-PU) was prepared by two-step polymerization of diisocyanate terminated polyethylene glycol and polycaprolactone with hydroxyl terminated AIE dye. A series of characterization techniques proved the successful synthesis of AIE-PU. Due to the amphiphilic chain segment of its linear block molecule, AIE-PU block copolymers can self-assemble into spherical nanoparticles in aqueous solution, showing relatively stable photophysical properties and good water dispersion. Cellular experiments demonstrated that AIE-PUs have low toxicity and high actin network affinity. Moreover, the uptake mechanism was studied by low temperature and metabolic inhibition experiments, showing that AIE-PU nanoparticles could be easily internalized into different living cells through energy-dependent endocytosis, and can be transported from the cellular periphery to the actin network via clathrin- and caveolae-dependent transport pathway. Upon binding with the actin network, the inter-chain AIE mechanism of the probe was significantly enhanced, which is pivotal for the long-term stable fluorescence imaging of actin microfilament network in living cells. Finally, compared with commercial actin dyes, this probe showed higher photostability, even after a longer retention time, without significant fluorescence quenching. [ABSTRACT FROM AUTHOR]

Highlights • The excellent and durable antimicrobial and anti-mite polyester fabrics are fabricated. • The finished PET fabrics exhibit excellent hydrophilic and antistatic properties. • Non-leaching antimicrobial PET fabrics exhibit no skin stimulation and toxicity. • The improved cohesive force between the fibers leading to enhanced tear strength. • The finished PET fabrics maintain mechanical properties and vapor/air permeability. Abstract Polyethylene terephthalate (PET) has been widely used in fabrics owing to its great mechanical properties, easy processability and quick drying. However, PET-based products always suffer from uncomfortable low sweat uptake and electrostatic charge buildup mainly due to its bad surface wettability. Moreover, porous fabrics may induce unfavorable mite and microorganism reproduction. Due to lack of reactive groups on the PET skeleton, it was very difficult to endow its surface hydrophilicity, antistatic properties, perdurable antimicrobial and anti-mite properties by conventional methods. In this work, we develop a one-step eco-friendly finishing strategy for PET fabrics through photochemical reaction using benzophenone group terminated quaternary ammonium salt (BP-QAS) as the finishing reagent. The as-finished PET fibers changed from incompact state to compact state due to the increased cohesive forces within individual fibers, resulting in improved tearing strength. The PET fabrics show significantly improved hydrophilicity, and antistatic properties. Furthermore, the as-finished PET fabrics exhibit excellent, durable broad-spectrum antimicrobial activities against gram-negative, gram-positive, drug-resistant bacteria and fungi. Moreover, our fabric shows long-lasting antimicrobial properties above AAA requirements after 50 laundering cycles. Usual PET fabrics generally have difficulty achieving AAA standards after 10 laundering cycles. In addition, our as-prepared fabrics showed excellent anti-mite activities against house dust mites based on disruption of the microbial and mite membrane due to oxidation stress, while no negative effects were observed for mouse and rabbit. The finished PET fabrics can be applied to multiple industries to prevent infectious diseases and improve public health, including but not limited to packaging, clothes, water treatment, and medical appliances. [ABSTRACT FROM AUTHOR]

Random copolymer gels of N-isopropylacrylamide (NIPAM) and N-ethylacrylamide (NEAM) are synthesized using different monomer compositions in 1:1 methanol-water mixtures. The samples are characterized by scanning electron microscopy, atomic force microscopy (AFM), and rheological studies. It is observed that with the variation of the monomer compositions in the reaction mixture, the thermoresponsive, morphological, AFM, and rheological properties varied significantly. Porosity and roughness of the gels gradually increase with the gradual increase in NIPAM loading in the gels, lower critical solution temperature, mechanical strength (Young's modulus, storage modulus) significantly decreases with the increase in poly( N-isopropylacrylamide) loading in the gels. All results can be explained on the basis of the differences in thermoresponsive character of homo- and copolymer gels of NIPAM and NEAM in water, their composition in the reaction mixtures, and their different kind of interactions with solvents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fabrication of Bi 2 Se 3 -GF and Bi 2 O 2 Se-GF samples in CVD. • A large magnetoresistance (MR) ∼250% is detected in Bi 2 Se 3 -GF compared to Bi 2 O 2 Se-GF. • This is due to large spin orbit coupling in Bi 2 Se 3 and presence of oxygen vaccines in Bi 2 O 2 Se. Herein, synergetic magnetoresiatnce of topological insulators such as Bismuth Selenium (Bi 2 Se 3) and Bismuth Oxygen Sileneium (Bi 2 O 2 Se), and GF is discussed in detail. Both, Bi 2 Se 3 -GF and Bi 2 O 2 Se-GF, are fabricated in Chemical Vapor Deposition (CVD) under argon and air atmosphere, respectively. The highest positive MR ∼250% is detected under a magnetic field ∼5 T and temperature ∼5 K in Bi 2 Se 3 -GF sample compared to Bi 2 O 2 Se-GF. The presence of oxygen in Bi 2 Se 3 to form Bi 2 O 2 Se significantly reduced the magnitude of MR and linear MR might be due to the mobility fluctuation. [ABSTRACT FROM AUTHOR]

Chemodynamic therapy (CDT) is an emerging treatment that usually employs chemical agents to decompose hydrogen peroxide (H2O2) into hydroxyl radical (•OH) via Fenton or Fenton‐like reactions, inducing cell apoptosis or necrosis by damaging biomacromolecules such as, lipids, proteins, and DNA. Generally, CDT shows high tumor‐specificity and minimal‐invasiveness in patients, thus it has attracted extensive research interests. However, the catalytic reaction efficiency of CDT is largely limited by the relatively high pH at the tumor sites. Herein, a 808 nm laser‐potentiated peroxidase catalytic/mild‐photothermal therapy of molybdenum diphosphide nanorods (MoP2 NRs) is developed to improve CDT performance, and simultaneously achieve effective tumor eradication and anti‐infection. In this system, MoP2 NRs exhibit a favorable cytocompatibility due to their inherent excellent elemental biocompatibility. Upon irradiation with an 808 nm laser, MoP2 NRs act as photosensitizers to efficiently capture the photo‐excited band electrons and valance band holes, exhibiting enhanced peroxidase‐like catalytic activity to sustainedly decompose tumor endogenous H2O2 to •OH, which subsequently destroy the cellular biomacromolecules both in tumor cells and bacteria. As demonstrated both in vitro and in vivo, this system exhibits a superior therapeutic efficiency with inappreciable toxicity. Hence, the work may provide a promising therapeutic technique for further clinical applications. [ABSTRACT FROM AUTHOR]

VO 2 exhibits metal-insulator transition (MIT) accompanied by structural phase transformation between rutile R phase and monoclinic M 1 phase, and an intermediate monoclinic phase M 2 may also emerge, stabilized by strain. The evolution of microstructures and properties across phase transition is not only critical for understanding the nature of MIT, but also important for numerous device applications, yet they are quite challenging to characterize. Utilizing advanced atomic force microscopy (AFM) techniques in combination with polarized light microscopy, X-ray diffraction, and Raman spectroscopy, we map the microstructure evolution of VO 2 when it is heated from room temperature M 1 phase to high temperature R phase through intermediate M 2 phase, and acquire functional imaging of VO 2 spanning these three phases as well. These result in quantitative mapping of electric conduction and Young's modulus of VO 2 in one-to-one correspondence to its domain patterns, especially those with austenite-martensite interface between M 2 and R phases. Young's modulus of M 1 , M 2 , and R phase of VO 2 are determined to be 95 GPa, 65-117 GPa, and 98-100 GPa respectively, and significant anisotropy is observed in M 2 phase. Rigorous continuum analysis has also been carried out to analyze the complicated domain pattern, validating our experimental observations that match theoretical expectation well. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The combination of thermoresponsive polymers with natural biomaterials can extend the properties portfolio, especially in the field of biomedicine, where a great cell adhesiveness and biodegradation is necessary for bone regeneration. The poly(N‐isopropylacrylamide)‐grafted‐gelatin gels were already reported where several synthetic parameters, such as polymer or gelatin were varied and final properties were studied. Nevertheless, the ratio of the cross‐linker was always the same, and consequently, their properties were not analyzed yet. There are various preparation methods of these systems but microwave synthesis was not deeply studied, and consequently, important benefits can be obtained due to its efficiency and time saving. In this work, we modified the ratio of cross‐linker and important changes are observed in the thermoresponsive and mechanical properties tested by calorimetry, thermogravimetry, rheology, and atomic force microscopy. The amount of cross‐linker modulates the homogeneity of the resulting gels, and consequently, the lower critical solution temperature, the absorption of water into surfaces and the mechanical behavior of the new materials. [ABSTRACT FROM AUTHOR]

Nanohybrids of graphene with water soluble polymer were synthesized using 'grafting from' method. GO, prepared by modified Hummers' method, was first reacted with sodium azide. Alkyne-terminated RAFT-CTA was synthesized by reaction of propargyl alcohol and S-1-dodecyl-S'-(α,α'-dimethyl-α'-acetic acid) trithiocarbonate. RAFT-CTA was grafted onto the GO sheets by facile click-reaction and subsequently, N-isopropylacrylamide (NIPAM) and N-ethyleacrylamide (NEAM) were polymerized on graphene sheets via RAFT polymerization method. The respective copolymers with different ratios were also prepared. The nanohybrids were characterized by FTIR, XRD, TGA, Raman, SEM, and AFM. Both SEM and AFM clearly showed rod-like structures for rGO-PNEAM. XRD showed a small peak at 2θ = 19.21°, corresponding to d-spacing ≈ 4.6 Å. In addition, the nanohybrids showed a very broad temperature range for the LCST in water between ca. 30 and 70 °C. [ABSTRACT FROM AUTHOR]

Background: Thanks to mechanotransductive components cells are competent to perceive nanoscale topographical features of their environment and to convert the immanent information into corresponding physiological responses. Due to its complex configuration, unraveling the role of the extracellular matrix is particularly challenging. Cell substrates with simplified topographical cues, fabricated by top-down micro- and nanofabrication approaches, have been useful in order to identify basic principles. However, the underlying molecular mechanisms of this conversion remain only partially understood. Results: Here we present the results of a broad, systematic and quantitative approach aimed at understanding how the surface nanoscale information is converted into cell response providing a profound causal link between mechanotransductive events, proceeding from the cell/nanostructure interface to the nucleus. We produced nanostructured ZrO2 substrates with disordered yet controlled topographic features by the bottom-up technique supersonic cluster beam deposition, i.e. the assembling of zirconia nanoparticles from the gas phase on a flat substrate through a supersonic expansion. We used PC12 cells, a well-established model in the context of neuronal differentiation. We found that the cell/nanotopography interaction enforces a nanoscopic architecture of the adhesion regions that affects the focal adhesion dynamics and the cytoskeletal organization, which thereby modulates the general biomechanical properties by decreasing the rigidity of the cell. The mechanotransduction impacts furthermore on transcription factors relevant for neuronal differentiation (e.g. CREB), and eventually the protein expression profile. Detailed proteomic data validated the observed differentiation. In particular, the abundance of proteins that are involved in adhesome and/or cytoskeletal organization is striking, and their up- or downregulation is in line with their demonstrated functions in neuronal differentiation processes. Conclusion: Our work provides a deep insight into the molecular mechanotransductive mechanisms that realize the conversion of the nanoscale topographical information of SCBD-fabricated surfaces into cellular responses, in this case neuronal differentiation. The results lay a profound cell biological foundation indicating the strong potential of these surfaces in promoting neuronal differentiation events which could be exploited for the development of prospective research and/or biomedical applications. These applications could be e.g. tools to study mechanotransductive processes, improved neural interfaces and circuits, or cell culture devices supporting neurogenic processes. [ABSTRACT FROM AUTHOR]

The molecular clutch (MC) model proposes that actomyosin-driven force transmission permits integrin-dependent cell migration. To investigate the MC, we introduced diverse talin (TLN) and integrin variants into Flp-In™ T-Rex™ HEK293 cells stably expressing uPAR. Vitronectin variants served as substrate providing uPAR-mediated cell adhesion and optionally integrin binding. This particular system allowed us to selectively analyse key MC proteins and interactions, effectively from the extracellular matrix substrate to intracellular f-actin, and to therewith study mechanobiological aspects of MC engagement also uncoupled from integrin/ligand binding. With this experimental approach, we found that for the initial PIP 2 -dependent membrane/TLN/f-actin linkage and persistent lamellipodia formation the C-terminal TLN actin binding site (ABS) is dispensable. The establishment of an adequate MC-mediated lamellipodial tension instead depends predominantly on the coupling of this C-terminal TLN ABS to the actomyosin-driven retrograde actin flow force. This lamellipodial tension is crucial for full integrin activation eventually determining integrin-dependent cell migration. In the integrin/ligand-independent condition the frictional membrane resistance participates to these processes. Integrin/ligand binding can also contribute but is not necessarily required. [ABSTRACT FROM AUTHOR]

The urokinase-type plasminogen activator receptor ( uPAR) is a non-integrin vitronectin (VN) cell adhesion receptor linked to the plasma membrane by a glycolipid anchor. Through structure-function analyses of uPAR, VN and integrins, we document that uPAR-mediated cell adhesion to VN triggers a novel type of integrin signalling that is independent of integrin-matrix engagement. The signalling is fully active on VN mutants deficient in integrin binding site and is also efficiently transduced by integrins deficient in ligand binding. Although integrin ligation is dispensable, signalling is crucially dependent upon an active conformation of the integrin and its association with intracellular adaptors such as talin. This non-canonical integrin signalling is not restricted to uPAR as it poses no structural constraints to the receptor mediating cell attachment. In contrast to canonical integrin signalling, where integrins form direct mechanical links between the ECM and the cytoskeleton, the molecular mechanism enabling the crosstalk between non-integrin adhesion receptors and integrins is dependent upon membrane tension. This suggests that for this type of signalling, the membrane represents a critical component of the molecular clutch. [ABSTRACT FROM AUTHOR]

Molybdenum Diphosphide Nanorods with Laser-Potentiated Peroxidase Catalytic/Mild-Photothermal Therapy of Oral Cancer (Adv. Sci. 1/2022) B Chemodynamic Therapy b In article number 2101527 by Yuehong Shen, Zhibin Li, Hongyu Yang, and co-workers, a promising therapeutic strategy of laser-potentiated peroxidase catalytic/mild-photothermal therapy of molybdenum diphosphide nanorods (MoP SB 2 sb NRs) is proposed to improve chemodynamic therapy (CDT) performance and achieve effective tumor eradication and anti-infection by decomposing tumor endogenous H SB 2 sb O SB 2 sb into •OH radicals. [Extracted from the article]

[Display omitted] • Hyaluronic acid (HA)-functionalized PLA tubular microfibers were designed and synthetized by electrospinning. • The resulting HA/PLA microfibers have no detectable trace of hemolysis and coagulation. • The HA/PLA microfibers promoted vascular endothelial cells proliferation and phenotypic expression. • The tubular HA/PLA based tubular scaffolds enhanced luminal pre-endothelialization of vascular ECs in vitro. This work was designed to evaluate the efficacy of hyaluronic acid (HA) functionalized tubular poly-lactic acid (PLA) microfibers in directing the luminal pre-endothelialization of vascular endothelial cells (ECs). Tubular HA/PLA microfibers with hierarchical architecture were prepared by electrospinning and chemical cross-linking process. A layer of HA microfibrous film coating was fixed on the inner wall surface of the tubular HA/PLA microfibers, resulting in higher anisotropy wettability and relatively lower surface energy and roughness. We confirmed that HA coating on PLA microfibers surface have reduced hemolytic activity and coagulation degree. Mouse vascular ECs exhibited surface-dependent differences in cell elongation and proliferation (HA/PLA > PLA). Compared with PLA microfibers, the gene expression levels of platelet EC adhesion molecule-1 (PECAM-1/CD31) and vascular endothelial growth factor (VEGF) in ECs of HA/PLA microfibers surface were up-regulated. Immunostaining analysis revealed that the surface of HA/PLA nanofibers supported the expression of mature vascular EC phenotype CD31 protein. In vitro co-culture analysis showed that the luminal pre-endothelialization induced vascular smooth muscle cells (SMCs) to maintain their phenotypic shape and establish natural behavior patterns in the hierarchical tubular scaffold. These studies indicate that the biophysical cues of scaffolds are potent regulators of vascular EC endothelialization. [ABSTRACT FROM AUTHOR]

Plasticity and functional diversity of macrophages play an important role in resisting pathogens invasion, tumor progression and tissue repair. At present, nanodrug formulations are becoming increasingly important to induce and control the functional diversity of macrophages. In this framework, the internalization process of nanodrugs is co-regulated by a complex interplay of biochemistry, cell physiology and cell mechanics. From a biophysical perspective, little is known about cellular mechanics' modulation induced by the nanodrug carrier's internalization. In this study, we used the polylactic-co-glycolic acid (PLGA)–polyethylene glycol (PEG) nanofibers as a model drug carrier, and we investigated their influence on macrophage mechanics. Interestingly, the nanofibers internalized in macrophages induced a local increase of stiffness detected by atomic force microscopy (AFM) nanomechanical investigation. Confocal laser scanning microscopy revealed a thickening of actin filaments around nanofibers during the internalization process. Following geometry and mechanical properties by AFM, indentation experiments are virtualized in a finite element model simulation. It turned out that it is necessary to include an additional actin wrapping layer around nanofiber in order to achieve similar reaction force of AFM experiments, consistent with confocal observation. The quantitative investigation of actin reconfiguration around internalized nanofibers can be exploited to develop novel strategies for drug delivery. [ABSTRACT FROM AUTHOR]