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The corneal epithelium is the outermost transparent barrier of the eyeball and undergoes continuous self‐renewal by limbal stem cells (LSCs) during its lifetime; however, the impact of aging on LSCs remains largely unknown. Here, we showed that the healing ability of the cornea in elderly macaques (Macaca fascicularis) was significantly decreased compared to that of younger macaques. This delayed wound closure accompanied a disordered cell arrangement and corneal opacity. A novel cytokine, Secreted and Transmembrane 1 (SECTM1), was found to facilitate corneal healing and was upregulated in young macaques upon wounding. Mechanistically, SECTM1 is essential for LSC migration and proliferation, and may partially function through Cell Division Cycle Associated 7 (CDCA7). Notably, the topical application of SECTM1 to aged wounded corneas dramatically promoted re‐epithelialization and improved corneal transparency in both mice and macaques. Our work suggests that aging may impair the expression of healing response factors and injury repair in non‐human primate corneas, and that SECTM1 application could potentially benefit corneal wound healing in clinical treatment. [ABSTRACT FROM AUTHOR]

We report a highly enantioselective intermolecular C−H bond silylation catalyzed by a phosphoramidite‐ligated iridium catalyst. Under reagent‐controlled protocols, propargylsilanes resulting from C(sp3)−H functionalization, as well the regioisomeric and synthetically versatile allenylsilanes, could be obtained with excellent levels of enantioselectivity and good to excellent control of propargyl/allenyl selectivity. In the case of unsymmetrical dialkyl acetylenes, good to excellent selectivity for functionalization at the less‐hindered site was also observed. A variety of electrophilic silyl sources (R3SiOTf and R3SiNTf2), either commercial or in situ‐generated, were used as the silylation reagents, and a broad range of simple and functionalized alkynes, including aryl alkyl acetylenes, dialkyl acetylenes, 1,3‐enynes, and drug derivatives were successfully employed as substrates. Detailed mechanistic experiments and DFT calculations suggest that an η3‐propargyl/allenyl Ir intermediate is generated upon π‐complexation‐assisted deprotonation and undergoes outer‐sphere attack by the electrophilic silylating reagent to give propargylic silanes, with the latter step identified as the enantiodetermining step. [ABSTRACT FROM AUTHOR]

We report a highly enantioselective intermolecular C−H bond silylation catalyzed by a phosphoramidite‐ligated iridium catalyst. Under reagent‐controlled protocols, propargylsilanes resulting from C(sp3)−H functionalization, as well the regioisomeric and synthetically versatile allenylsilanes, could be obtained with excellent levels of enantioselectivity and good to excellent control of propargyl/allenyl selectivity. In the case of unsymmetrical dialkyl acetylenes, good to excellent selectivity for functionalization at the less‐hindered site was also observed. A variety of electrophilic silyl sources (R3SiOTf and R3SiNTf2), either commercial or in situ‐generated, were used as the silylation reagents, and a broad range of simple and functionalized alkynes, including aryl alkyl acetylenes, dialkyl acetylenes, 1,3‐enynes, and drug derivatives were successfully employed as substrates. Detailed mechanistic experiments and DFT calculations suggest that an η3‐propargyl/allenyl Ir intermediate is generated upon π‐complexation‐assisted deprotonation and undergoes outer‐sphere attack by the electrophilic silylating reagent to give propargylic silanes, with the latter step identified as the enantiodetermining step. [ABSTRACT FROM AUTHOR]

Titanium niobium oxide (TNO) exhibits great potential as a lithium‐ion battery anode due to its high capacity, minimal volume change during cycling, and safe good operation characteristic enabled from its voltage profile. However, its intrinsically low electronic and ionic conductivity hinders its potential for practical applications. This work proposes a facile coprecipitation method to address these limitations by incorporating a nano‐macro structure and in situ Sn ion doping into bulk TNO. This approach ensures homogeneous integration of TNO precursors and the Sn dopant at a molecular level within the co‐precipitation nanoparticles. Additionally, the use of low toxicity solvents facilitate scalability of the synthesis process. Excellent rate capability, high reversible capacities, and good capacity retention are achieved simultaneously due to synergistic effects of the bulk doping, which expands the crystal volume and enhances Li+ diffusion, combined with abundant surface area of the nano‐macro structures. The specific capacity of Sn‐doped TNO nanospheres remains at 180 mAh/g at a high current density of 40 C (1 C=400 mA g−1), which is nearly four times higher than that of undoped samples. Furthermore, the cyclic voltammetry analysis at various scanning rates reveals an increased Li+ diffusion rate in Sn doped titanium niobium dioxide. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (H. pylori) infection is the primary risk factor for the pathogenesis of gastric cancer (GC). N6‐methyladenosine (m6A) plays pivotal roles in mRNA metabolism and hnRNPA2B1 as an m6A reader is shown to exert m6A‐dependent mRNA stabilization in cancer. This study aims to explore the role of hnRNPA2B1 in H. pylori‐associated GC and its novel molecular mechanism. Multiple datasets and tissue microarray are utilized for assessing hnRNPA2B1 expression in response to H. pylori infection and its clinical prognosis in patients with GC. The roles of hnRNPA2B1 are investigated through a variety of techniques including glucose metabolism analysis, m6A‐epitranscriptomic microarray, Ribo‐seq, polysome profiling, RIP‐seq. In addition, hnRNPA2B1 interaction with poly(A) binding protein cytoplasmic 1 (PABPC1) is validated using mass spectrometry and co‐IP. These results show that hnRNPA2B1 is upregulated in GC and correlated with poor prognosis. H. pylori infection induces hnRNPA2B1 upregulation through recruiting NF‐κB to its promoter. Intriguingly, cytoplasm‐anchored hnRNPA2B1 coordinated PABPC1 to stabilize its relationship with cap‐binding eIF4F complex, which facilitated the translation of CIP2A, DLAT and GPX1 independent of m6A modification. In summary, hnRNPA2B1 facilitates the non‐m6A translation of epigenetic mRNAs in GC progression by interacting with PABPC1‐eIF4F complex and predicts poor prognosis for patients with GC. [ABSTRACT FROM AUTHOR]

Dithioacetals are heavily used in organic, material and medical chemistries, and exhibit huge potential to synthesize degradable or recyclable polymers. However, the current synthetic approaches of dithioacetals and polydithioacetals are overwhelmingly dependent on external catalysts and organic solvents. Herein, we disclose a catalyst‐ and solvent‐free acetal‐thiol click‐like reaction for synthesizing dithioacetals and polydithioacetals. High conversion, higher than acid catalytic acetal‐thiol reaction, can be achieved. High universality was confirmed by monitoring the reactions of linear and cyclic acetals (including renewable bio‐sourced furan‐acetal) with aliphatic and aromatic thiols, and the reaction mechanism of monomolecular nucleophilic substitution (SN1) and auto‐protonation (activation) by thiol was clarified by combining experiments and density functional theory computation. Subsequently, we utilize this reaction to synthesize readily recyclable polydithioacetals. By simple heating and stirring, linear polydithioacetals with M‾ ${\bar M}$ w of ~110 kDa were synthesized from acetal and dithiol, and depolymerization into macrocyclic dithioacetal and repolymerization into polydithioacetal can be achieved; through reactive extrusion, a semi‐interpenetrating polymer dynamic network with excellent mechanical properties and continuous reprocessability was prepared from poly(vinyl butyral) and pentaerythritol tetrakis(3‐mercaptopropionate). This green and high‐efficient synthesis method for dithioacetals and polydithioacetals is beneficial to the sustainable development of chemistry. [ABSTRACT FROM AUTHOR]

Dithioacetals are heavily used in organic, material and medical chemistries, and exhibit huge potential to synthesize degradable or recyclable polymers. However, the current synthetic approaches of dithioacetals and polydithioacetals are overwhelmingly dependent on external catalysts and organic solvents. Herein, we disclose a catalyst‐ and solvent‐free acetal‐thiol click‐like reaction for synthesizing dithioacetals and polydithioacetals. High conversion, higher than acid catalytic acetal‐thiol reaction, can be achieved. High universality was confirmed by monitoring the reactions of linear and cyclic acetals (including renewable bio‐sourced furan‐acetal) with aliphatic and aromatic thiols, and the reaction mechanism of monomolecular nucleophilic substitution (SN1) and auto‐protonation (activation) by thiol was clarified by combining experiments and density functional theory computation. Subsequently, we utilize this reaction to synthesize readily recyclable polydithioacetals. By simple heating and stirring, linear polydithioacetals with M‾ ${\bar M}$ w of ~110 kDa were synthesized from acetal and dithiol, and depolymerization into macrocyclic dithioacetal and repolymerization into polydithioacetal can be achieved; through reactive extrusion, a semi‐interpenetrating polymer dynamic network with excellent mechanical properties and continuous reprocessability was prepared from poly(vinyl butyral) and pentaerythritol tetrakis(3‐mercaptopropionate). This green and high‐efficient synthesis method for dithioacetals and polydithioacetals is beneficial to the sustainable development of chemistry. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) is an important antioxidant that is generated and degraded via the GSH cycle. Quantification of the main components in the GSH cycle is necessary to evaluate the process of GSH. In this study, a robust ultra‐performance liquid chromatography‐tandem mass spectrometry method for the simultaneous quantification of 10 components (GSH; γ‐glutamylcysteine; cysteinyl‐glycine; n‐acetylcysteine; homocysteine; cysteine; cystine; methionine; glutamate; pyroglutamic acid) in GSH cycle was developed. The approach was optimized in terms of derivative, chromatographic, and spectrometric conditions as well as sample preparation. The unstable thiol groups of GSH, γ‐glutamylcysteine, cysteinyl‐glycine, n‐acetylcysteine, cysteine, and homocysteine were derivatized by n‐ethylmaleimide. The derivatized and underivatized analytes were separated on an amino column with gradient elution. The method was further validated in terms of selectivity (no interference), linearity (R2 > 0.99), precision (% relative standard deviation [RSD%] range from 0.57 to 10.33), accuracy (% relative error [RE%] range from ‐3.42 to 10.92), stability (RSD% < 5.68, RE% range from ‐2.54 to 4.40), recovery (RSD% range from 1.87 to 7.87) and matrix effect (RSD% < 5.42). The validated method was applied to compare the components in the GSH cycle between normal and oxidative stress cells, which would be helpful in clarifying the effect of oxidative stress on the GSH cycle. [ABSTRACT FROM AUTHOR]

In the burgeoning field of bioinspired materials, the principles governing biological perception and self‐healing drive advancements in biomimetic mechano‐responsive materials, seamlessly integrating ionic signal sensing with self‐healing. While current research often emphasizes individual functionalities, the concurrent enhancement of both self‐healing and sensitivity in iontronic skins is often overlooked. Drawing inspiration from transmembrane proteins like TSP‐15, Piezo 1 and Piezo 2, renowned for recruiting repair factors, multifunctional molecular‐ionic regulatory sites are constructed within a polyurethane/ionic liquid composite system, leading to the development of a mechano‐responsive elastomer (i‐DAPU) that exhibited both rapid self‐healing (72 µm min−1) and impressive sensitivity (7012.05 kPa−1). Leveraging the dual functionalities of i‐DAPU in tandem with deep learning algorithms, a sophisticated system is devised for intelligently analyzing neural conditions in comatose patients based on muscle strength, achieving a remarkable 99.2% accuracy rate, holding significant promise for healthcare applications. [ABSTRACT FROM AUTHOR]

Vitrimers represent an emerging class of polymeric materials that combine the desirable characteristics of both thermoplastics and thermosets achieved through the design of dynamic covalent bonds within the polymer networks. However, these materials are prone to creep due to the inherent instability of dynamic covalent bonds. Consequently, there are pressing demands for the development of robust and stable dynamic covalent chemistries. Here, we report a catalyst‐free α‐acetyl cinnamate/acetoacetate (α‐AC/A) exchange reaction to develop vitrimers with remarkable creep resistance. Small‐molecule model studies revealed that the α‐AC/A exchange occurred at temperatures above 140 °C in bulk, whereas at 120 °C, this reaction was absent. For demonstration in the case of polymers, copolymers derived from common vinyl monomers were crosslinked with terephthalaldehyde to produce α‐AC/A vitrimers with tunable thermal and mechanical performance. All resulting α‐AC/A vitrimers exhibited high stability, especially in terms of creep resistance at 120 °C, while retaining commendable reprocessability when subjected to high temperatures. This work showcases the α‐AC/A exchange reaction as a novel and robust dynamic covalent chemistry capable of imparting both reprocessability and high stability to cross‐linked networks. [ABSTRACT FROM AUTHOR]

Vitrimers represent an emerging class of polymeric materials that combine the desirable characteristics of both thermoplastics and thermosets achieved through the design of dynamic covalent bonds within the polymer networks. However, these materials are prone to creep due to the inherent instability of dynamic covalent bonds. Consequently, there are pressing demands for the development of robust and stable dynamic covalent chemistries. Here, we report a catalyst‐free α‐acetyl cinnamate/acetoacetate (α‐AC/A) exchange reaction to develop vitrimers with remarkable creep resistance. Small‐molecule model studies revealed that the α‐AC/A exchange occurred at temperatures above 140 °C in bulk, whereas at 120 °C, this reaction was absent. For demonstration in the case of polymers, copolymers derived from common vinyl monomers were crosslinked with terephthalaldehyde to produce α‐AC/A vitrimers with tunable thermal and mechanical performance. All resulting α‐AC/A vitrimers exhibited high stability, especially in terms of creep resistance at 120 °C, while retaining commendable reprocessability when subjected to high temperatures. This work showcases the α‐AC/A exchange reaction as a novel and robust dynamic covalent chemistry capable of imparting both reprocessability and high stability to cross‐linked networks. [ABSTRACT FROM AUTHOR]

In this work, two kinds of biomass fillers including reed and wheat straw with similar sizes at micrometer scale were used as filler and poly(butyleneadipate‐co‐terephthalate) (PBAT) as matrix to prepare high‐performance composite materials and to use for the research of enzymatic degradation. Accordingly, hard PBAT composites with average bending strength and modulus at 12 and 1100 MPa were prepared. With the progress of enzymatic degradation, water absorption of the biomass fillers to promote the degradation of PBAT matrix was clearly revealed. The strong water absorption of biomass filler led to the large degradation rate. During the degradation within 90 days, the mechanical properties of PBAT/biomass fillers composites decreased to 23.7%. This study revealed the important factors of biomass fillers affecting the degradation behavior of PBAT in composite. Highlights: • Two different biomass fillers are blended into PBAT to fabricate the composites. • All of the biomass fillers are similarly controlled at the micrometer level. • Water absorption of biomass filler promotes the degradation of the PBAT matrix. • Stronger water absorption induces quicker degradation rate. • After degradation, bending properties of PBAT composites obviously decrease. [ABSTRACT FROM AUTHOR]

Background and Purpose: Glial cell‐derived neurotrophic factor (GDNF) maintains gut homeostasis. Dopamine promotes GDNF release in astrocytes. We investigated the regulation by dopamine of colonic GDNF secretion. Experimental Approach: D1 receptor knockout (D1R−/−) mice, adeno‐associated viral 9‐short hairpin RNA carrying D2 receptor (AAV9‐shD2R)‐treated mice, 6‐hydroxydopamine treated (6‐OHDA) rats and primary enteric glial cells (EGCs) culture were used. Incubation fluid from colonic submucosal plexus and longitudinal muscle myenteric plexus were collected for GDNF and ACh measurements. Key Results: D2 receptor‐immunoreactivity (IR), but not D1 receptor‐IR, was observed on EGCs. Both D1 receptor‐IR and D2 receptor‐IR were co‐localized on cholinergic neurons. Low concentrations of dopamine induced colonic GDNF secretion in a concentration‐dependent manner, which was mimicked by the D1 receptor agonist SKF38393, inhibited by TTX and atropine and eliminated in D1R−/− mice. SKF38393‐induced colonic ACh release was absent in D1R−/− mice. High concentrations of dopamine suppressed colonic GDNF secretion, which was mimicked by the D2 receptor agonist quinpirole, and absent in AAV‐shD2R‐treated mice. Quinpirole decreased GDNF secretion by reducing intracellular Ca2+ levels in primary cultured EGCs. Carbachol (ACh analogue) promoted the release of GDNF. Quinpirole inhibited colonic ACh release, which was eliminated in the AAV9‐shD2R‐treated mice. 6‐OHDA treated rats with low ACh and high dopamine content showed decreased GDNF content and increased mucosal permeability in the colon. Conclusion and Implications: Low concentrations of dopamine promote colonic GDNF secretion via D1 receptors on cholinergic neurons, whereas high concentrations of dopamine inhibit GDNF secretion via D2 receptors on EGCs and/or cholinergic neurons. [ABSTRACT FROM AUTHOR]

Synopsis: Postoperative non‐invasive mucosal implantation of cervical adenocarcinoma on the clitoris is rare. Surgical resection is appropriate for local recurrence in the vulva. [ABSTRACT FROM AUTHOR]

In the pursuit of tactile sensation resembling human skin, the electronic skin (E‐skin) has long been a subject of interest and inspires the exploration of various biomimetic structures. Nevertheless, the exceptional functionality of living organisms arises from the synergistic interplay of multiple internal factors, i.e. the coupling enhancement effect, which has received limited attention in existing studies. Here, a tactile E‐skin featuring a multicoupled biomimetic structure that mimics three coupling elements found in the skin: Stratum spinosum, Meissner corpuscle, and Piezo2 protein, is proposed. By amalgamating their distinguishing characteristics, this bionic E‐skin surpasses the performance of conventional counterparts such as sensitivity as high as 388.5 kPa−1, hysteresis as low as 0.76%, and response times as short as 10 ms. Furthermore, its fabrication methodology of efficient 3D printing shows great advantages in terms of production cost and customization. Finally, the sensor is expanded to a 9 × 9 pixels array for a machine learning‐assisted intellisense system to recognize the fruits as a human does, achieving an accuracy of 91.4%. All of these prove the promising potential of this multicoupled biomimetic structure in wearable electronics, human–machine interface, soft robotics, and artificial sensing. [ABSTRACT FROM AUTHOR]

Owing to the inferior dispersibility of boron nitride nanosheets (BNNSs) and weak interfacial interaction with the matrix, the performance of BNNS‐based composites is usually far below theoretically predicted values. Here, binary multiscale BNNSs (LDH‐BNNSs) fillers are synthesized through in situ growth of layered double hydroxide (LDH) on the BNNSs' surfaces. LDH‐BNNSs with a multiple mosaic interface show superior dispersion of nanosheets in matrix and extraordinary filler‐matrix bonding. Density functional theory simulations reveal the stable dispersion mechanism of LDH‐BNNSs. Moreover, the bio‐based poly(ethylene furandicarboxylate) composites with 0.2 wt% LDH‐BNNSs loading exhibit simultaneous improvements in tensile strength (≈140 MPa), Young's modulus (≈6.5 GPa), toughness (≈2.0 MJ m−3), and gas barrier properties. Regulation of the interfacial structures of binary multiscale BNNSs significantly increases the filler utilization of the nanosheets, leading to extraordinary stress transfer efficiency and a physical shielding effect. Therefore, this simple, efficient, and novel strategy has promised in enhancing composite performance, and it provides a novel way to develop strong, tough, and high‐barrier bio‐based polyester composites. [ABSTRACT FROM AUTHOR]

Objectives: Scaphoid nonunion remains a challenging problem to manage with no general consensus on its treatment recommendations. We propose a novel minimally invasive (MIS) technique of arthroscopic bone grafting (ABG) with robot‐assisted fixation for the treatment of scaphoid nonunions. Methods: Patients with radiographically proven scaphoid nonunion treated by this novel surgical technique were included. Following arthroscopic debridement and iliac crest bone grafting, the scaphoid was fixed percutaneously using either multiple Kirschner (K)‐wires or a headless compression screw using a robotic navigation system. Results: Six male patients with an average age of 29.2 years were enrolled. Four patients had scaphoid waist fractures, and the other two were proximal pole fractures. During wrist arthroscopy, punctate bleeding of the proximal scaphoid fragment was observed in four out of the six patients. Half of the patients were fixed using a headless compression screw and the other half using multiple K‐wires. All the guidewires were placed with a single‐attempt using the robotic navigation system. Postoperatively, all the scaphoid fractures had complete radiographic union by 16 weeks. At a mean follow‐up of 18.3 months, there were significant improvements in wrist range of motion, grip strength, and patient‐rated outcomes. No intraoperative or early postoperative complications were encountered in any of our patients. Conclusion: Arthroscopic bone grafting with robot‐assisted fixation is a feasible and promising therapeutic option for scaphoid nonunions, regardless of the vascularity of the proximal pole fragment. This novel technique allows for anatomic restoration of the scaphoid alignment and accurate, targeted placement of implants into the scaphoid nonunion site within a single‐attempt using a robotic navigation system. [ABSTRACT FROM AUTHOR]