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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]

Background: Probiotics comprise effective feed additives that can replace antibiotics in animal livestock production. However, mono‐strain probiotics appear less effective because of their instability. Therefore, the present study aimed to investigate dietary supplementation with compound probiotics (CPP) on growth performance, diarrhea rate and intestinal mucosal barrier, as well as the possible molecular mechanism, in chicks. In total, 360 1‐day‐old chicks of the Hy‐Line Brown Chicks were randomly divided into the control group (CON, basal diet), chlortetracycline group (500 mg kg−1 CTC) and compound probiotics group (1000 mg kg−1 CPP, consisting of Bacillus subtilis, Bacillus licheniformis, Enterococcus faecium and yeast). The experiment period was 56 days. Results: The results showed that, in comparison with the CON group, CPP significantly increased the average daily feed intake and average daily gain of chicks and reduced diarrhea (P < 0.05). The probiotic group exhibited increased immune organ (i.e. spleen and thymus) mass and increased levels of serum immunoglobulin (Ig)A, IgM and IgG (P < 0.05) compared to the CTC group. In addition, the jejunal mass and morphology were improved in the probiotic group (P < 0.05). Moreover, CPP reinforced jejunal barrier function, as indicated by increased transepithelial electrical resistance, protein expression of occludin and claudin‐1, and diamine oxidase levels in the jejunum (P < 0.05). Likewise, enhanced fluorescence signals of proliferating cell nuclear antigen‐labeled mitotic cells and villin‐labeled absorptive cells in the jejunum (P < 0.05) suggested that CPP promoted intestinal stem cells activity. Mechanistically, the Wnt/β‐catenin signaling pathway, including β‐catenin, TCF4, c‐Myc, cyclin D1 and Lgr5, was amplified in the jejunum by CPP addition (P < 0.05). Conclusion: The present study demonstrated that dietary supplementation with CPP reinforced the jejunal epithelial integrity by activating Wnt/β‐catenin signaling and enhanced immune function in chicks. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Regenerated wool keratin fibers (RWKFs) have heretofore attracted tremendous interest according to environmental friendliness, ample resource, and intrinsic biocompatibility for broad applications. In this realm, both uncontrollable keratin fibril assembly procedure and resultant insufficient mechanical strength, have greatly hindered their large‐scale manufacture and commercial viability. Herein, a continuous wet‐spinning strategy is put forward to rebuild wool keratin into compact regenerated bio‐fibers with improved strength via disulfide re‐bonding. Dithiothreitol (DTT) has been introduced to renovate disulfide linkage inside keratin polypeptide chains, and bridge keratin fibrils via covalent thiol bonding to form a continuous backbone as mechanical support. A thus‐derived RWKF manifests a tensile strength of 186.1 ± 7.0 MPa and Young's modulus of 7.4 ± 0.2 GPa, which exceeds those of natural wool, feathers, and regenerated wool or feather keratin fibers. The detailed wet‐spinning technical parameters, such as coagulation, oxidation, and post‐treatment, have been systematically optimized to guarantee the continuous preparation of high‐strength regenerated keratin fibers. This work offers insight into solving the concurrent challenges for continuous manufacture of regenerated protein fibers and sustainability concerns about biomass waste. [ABSTRACT FROM AUTHOR]

Summary: The asynchronous filtering problem for networked fuzzy non‐homogeneous Markov jump systems is investigated, with the consideration of packet dropout and quantization. An event‐triggered dynamic quantization scheme is proposed, and a stability criterion is given to ensure the stochastic stability of the filtering error systems with desired extended dissipative performance. This performance provides a unified framework in the sense that it can degenerate to H∞$$ {H}_{\infty } $$, l2−l∞$$ {l}_2-{l}_{\infty } $$, dissipativity and passivity filter, respectively, under certain parameter sets. Furthermore, an asynchronous filter design method with extended dissipative performance is given based on the proposed stability criterion. In this method, the existence of the quantizer is ensured by dynamic quantization levels and the solution scope of the filter is enlarged by a free‐connection weighting matrices method. The theoretical design and analysis is finally evaluated using a practical example. [ABSTRACT FROM AUTHOR]

In this paper, a stabilization scheme for a class of continuous‐time nonlinear Markov jump systems is investigated by sampled‐data control mechanism. This stabilization scheme is given in the form of a discrete‐time state feedback controller which is designed based on the approximate discrete‐time model (ADTM) of the original continuous‐time system via the discrete‐time design method. During the process of controller design, an appropriate iteration step size is selected for the ADTM to restore the missing intersampling data due to the sampling characteristics, and this provides the iteration solutions of ADTM to the controller. The introduction of the iteration step size achieves a perfect tradeoff between calculation precision and control cost which not only guarantees the calculation precision of the ADTM, but also reduces sampling frequency effectively. Subsequently, we analyze the consistency condition between the continuous‐time nonlinear Markov jump systems and its ADTM, and give the criterion of the mean‐square exponential stability of the system. Based on this criterion, we prove the mean‐square exponential stability of the closed‐loop sampled‐data system with the designed discrete‐time state feedback controller. Finally, the feasibility and effectiveness of this scheme are clearly verified by a numerical example. [ABSTRACT FROM AUTHOR]

Background: The mechanisms of vagal nerve stimulation (VNS) for the treatment of drug‐resistant epilepsy (DRE) remain unclear. This study aimed to measure spontaneous brain activity changes caused by VNS in DRE patients using resting‐state functional MRI (rs‐fMRI). Methods: The rs‐fMRI scans were performed in 16 DRE patients who underwent VNS surgery. Amplitude of low‐frequency fluctuations (ALFF) and regional homogeneity (ReHo) was generated and examined using paired sample t‐test to compare activity changes at different current intensity stage. The preoperative and postoperative ALFF/ReHo were also compared in eight responders (≥50% reduction of seizure frequency three months after surgery) and eight nonresponders using paired sample t‐test. Results: The significant ALFF and ReHo changes were shown in various cortical/subcortical structures in patients under different current intensity. After three months of stimulation, responders exhibited increased ALFF in the right middle cingulate gyrus, left parahippocampal gyrus, and left cerebellum, and increased ReHo in the right postcentral gyrus, left precuneus, left postcentral gyrus, right superior parietal gyrus, right precentral gyrus, and right superior frontal gyrus. Nonresponders exhibited decreased ALFF in the left temporal lobe and right cerebellum, increased ALFF in bilateral brainstem, decreased ReHo in bilateral lingual gyri, and increased ReHo in the right middle frontal gyrus and right anterior cingulate gyrus. Conclusions: The spontaneous neural activity changes in DRE patients caused by VNS were in an ongoing process. Increased ALFF/ReHo in frontal cortex, cingulate gyri, precentral/postcentral gyri, parahippocampal gyri, precuneus, parietal cortex, and cerebellum may implicate in VNS‐induced improvement in seizure frequency. [ABSTRACT FROM AUTHOR]

Facial paralysis can result in severe implications for patients. A good prognosis depends on the degree of nerve regeneration. Schwann cells (SCs) play an important role in facial nerve development and regeneration through migration. Forkhead box C1 (Foxc1), a member of the forkhead transcription factor family, is implicated in cell migration. However, the role of Foxc1 in the progression after facial nerve crush remains unknown. Our aim was to evaluate the effect of Foxc1 overexpression on SC migration and recovery of facial nerves after crush injury. The rat facial nerve crush injury model was established through the use of unilateral surgery. The results showed that the expression of Foxc1 was increased in the surgery group compared to that of the control group. SCs were isolated from the sciatic nerves and cultured. Foxc1, delivered by an adeno‐associated virus in vivo, or adenovirus in vitro, both induced overexpression of Foxc1, and increased the expression of CXCL12 and β‐catenin. After the transfection of Foxc1, the migration of SC was increased both in vitro and in vivo, was reduced by the inhibition of CXCL12 or β‐catenin. The facial nerve function and the nerve axon remyelination of the rats transfected with Foxc1 were significantly improved after nerve crush injury. Overall, the results demonstrated that overexpression of Foxc1 promoted SC migration by regulating CXCL12 via the Wnt/β‐catenin pathway, thus contributing to improved facial nerve function after crush injury. [ABSTRACT FROM AUTHOR]

Background: Cervical vagus nerve stimulation (VNS) is an effective neuromodulation therapy for patients with drug‐resistant epilepsy (DRE). The previous studies reported that VNS may reduce seizures by regulating the functional connectivity (FC) between cortical and subcortical regions. However, no studies on brainstem have been done in responders who achieved ≥50% seizure reduction following VNS. Methods: Eight healthy controls and eight patients who became responders after 3 months of operation were enrolled in this study. Resting‐state functional MRI (rs‐fMRI) was performed, and two sample and paired sample t test were, respectively, used to detect altered FC between brainstem and cortical/subcortical regions between controls and patients, between preoperative and postoperative patients. Results: In the control group, regions with highest FC to brainstem included bilateral anterior cingulate gyri, left basal ganglia, left insula, left cuneus, right precuneus, and bilateral cerebellum. In preoperative patients, right frontal middle gyrus, bilateral basal ganglia, and right cerebellum were showed highest FC to brainstem. Compared with the controls, preoperative patients exhibited increased FC in bilateral inferior frontal gyri, right temporal cortex, while decreased FC in left insula, left postcentral gyrus, right posterior cingulate gyrus, right precuneus, and left superior parietal gyrus. In postoperative patients, regions with increased FC to brainstem were left insula, left precuneus and left cuneus, and those with decreased FC were right inferior occipital gyrus and right cerebellum. Conclusions: Recurrent seizures caused disturbances in brainstem‐cortical/subcortical FC, especially in motor executive function related regions and default mode network. VNS could reorganize the altered FC between brainstem and insula, precuneus, and cerebellum in responders. [ABSTRACT FROM AUTHOR]

Many factors are involved in the process of nerve regeneration. Understanding the mechanisms regarding how these factors promote an efficient remyelination is crucial to deciphering the molecular and cellular processes required to promote nerve repair. Schwann cells (SCs) play a central role in the process of peripheral nerve repair/regeneration. Using a model of facial nerve crush injury and repair, we identified Annexin A1 (ANXA1) as the extracellular trigger of SC proliferation and migration. ANXA1 activated formyl peptide receptor 2 (FPR2) receptors and the downstream adenosine 5′‐monophosphate (AMP)‐activated protein kinase (AMPK) signaling cascade, leading to SC proliferation and migration in vitro. SCs lacking FPR2 or AMPK displayed a defect in proliferation and migration. After facial nerve injury (FNI), ANXA1 promoted the proliferation of SCs and nerve regeneration in vivo. Collectively, these data identified the ANXA1/FPR2/AMPK axis as an important pathway in SC proliferation and migration. ANXA1‐induced remyelination and SC proliferation promotes FNI regeneration. [ABSTRACT FROM AUTHOR]

An iodine‐catalyzed [3+2] cycloaddition/ring opening reaction of 1,1‐diacylcyclopropanes with sulfonyl hydrazides has been reported. In the presence of 20 mol‐% iodine, a range of structurally diverse fully substituted pyrazoles with a hydroxy functional group are obtained in moderate to excellent yields with extremely high regioselectivity. [ABSTRACT FROM AUTHOR]

Summary: In this article, the state and mode feedback control strategy is investigated for the discrete‐time Markovian jump linear system (MJLS) with time‐varying controllable mode transition probability matrix (MTPM). This strategy, consisting of a state feedback controller and a mode feedback controller, is proposed to ensure MJLS's stability and meanwhile improve system performance. First, a mode‐dependent state feedback controller is designed to stabilize the MJLS based on the time‐invariant part of the MTPM such that it can still keep valid even if the MTPM is adjusted by the mode feedback control. Second, a generalized quadratic stabilization cost is put forward for evaluating MJLS's performance, which contains system state, state feedback controller, and mode feedback controller. To reduce the stabilization cost, a mode feedback controller is introduced to adjust each mode's occurrence probability by changing the time‐varying controllable part of MTPM. The calculation of such mode feedback controller is given based on a value‐iteration algorithm with its convergence proof. Compared with traditional state feedback control strategy, this state and mode feedback control strategy offers a new perspective for the control problem of general nonhomogeneous MJLSs. Numerical examples are provided to illustrate the validity of the proposed strategy. [ABSTRACT FROM AUTHOR]

Summary: This study focuses on the asynchronous ℋ∞ control problem for two‐dimensional discrete‐time hidden Markovian jump systems where the mode observation conditional probability matrix is partly known. Considering the original system modes are invisible, the observed modes emitted from an observer serve as an alternative for stability analysis and controller design where a mode observation conditional probability matrix is constructed to characterize the emission between system modes and observed modes. Specially, only partly known information of the mode observation conditional probability matrix is accessible. With the introduction of the free‐connection weighting matrices, the asymptotic mean square stability criterion is firstly derived based on Lyapunov method. This introduction provides a further degree of relaxation and less conservatism is therefore achieved. Secondly, we present synthesis conditions for asynchronous ℋ∞ state feedback controller design given in terms of a set of interconnected linear matrix inequalities. Moreover, cluster concept based on the partitions of observed modes is adopted which helps to decrease the number of controllers and simplify the design complexity. A numerical example, regarding the cases with and without clustering of the observed modes, is presented to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Both phototropins (phot1 and phot2) and cryptochromes (cry1 and cry2) were proven as the Arabidopsis thaliana blue light receptors. Phototropins predominately function in photomovement, and cryptochromes play a role in photomorphogenesis. Although cryptochromes have been proposed to serve as positive modulators of phototropic responses, the underlying mechanism remains unknown. Here, we report that depleting sucrose from the medium or adding gibberellic acids (GAs) can partially restore the defects in phototropic curvature of the phot1 phot2 double mutants under high‐intensity blue light; this restoration does not occur in phot1 phot2 cry1 cry2 quadruple mutants and nph3 (nonphototropic hypocotyl 3) mutants which were impaired phototropic response in sucrose‐containing medium. These results indicate that GAs and sucrose antagonistically regulate hypocotyl phototropism in a cryptochromes dependent manner, but it showed a crosstalk with phototropin signaling on NPH3. Furthermore, cryptochromes activation by blue light inhibit GAs synthesis, thus stabilizing DELLAs to block hypocotyl growth, which result in the higher GAs content in the shade side than the lit side of hypocotyl to support the asymmetric growth of hypocotyl. Through modulation of the abundance of DELLAs by sucrose depletion or added GAs, it revealed that cryptochromes have a function in mediating phototropic curvature. [ABSTRACT FROM AUTHOR]

Abstract Text. A general method for the synthesis of structural diversity and complexity of azepines from aldimine esters and β′‐acetoxy allenoates is reported. Under phosphine catalysis, a [4+3] cycloaddition for the formation of 1,3‐dihydro‐2H‐azepine‐2,2,4‐tricarboxylates was achieved with broad substrate scope under mild reactions. A switchable process was given and a variety of important 2,3‐dihydrochromeno[4,3‐b]azepin‐6(1H)‐ones were selectively formed when the reaction was performed in the presence of Cs2CO3 and PPh3, which involved an intramolecular ester group migration and subsequent lactonization of 1,3‐dihydro‐2H‐azepine‐2,2,4‐tricarboxylates. Besides easy handle process, high synthetic value of resulting products, it is worth to note that this work showed the novel example of 1,5‐ethoxycarbonyl migration. [ABSTRACT FROM AUTHOR]

Probabilistic load flow (PLF) is an important tool in power system planning and operation. One limitation of conventional PLF is that only the probability information of random variables is obtained as a reference for related analyses. Frequency and duration information often plays an important role in power system assessment. In this study, a frequency and duration method for PLF with correlated wind power sources and loads is proposed based on Latin hypercube sampling (LHS), Nataf transformation, and Markov chains. In the proposed method, the spatial and temporal correlations among wind power sources and loads are addressed using Nataf transformation and Markov chains, which are incorporated into the LHS framework to solve the PLF problem with frequency and duration quantities. With the proposed method, not only the probability information but also the frequency and duration information of the random output variables in a PLF problem can be efficiently and accurately obtained. The performance of the proposed PLF method is verified using comparative tests on three modified test systems. [ABSTRACT FROM AUTHOR]

Dear Editor, The 2017 World Health Organization classification of lymphoid neoplasms used the term "hydroa vacciniforme-like lymphoproliferative disorder (HVLPD)" to represent the Epstein-Barr virus (EBV) associated hydroa vacciniforme-like lesions1 and replace various names previously reported, including hydroa vacciniforme-like lymphoma (HVLL), hydroa vacciniforme-like cutaneous T-cell lymphoma, and severe hydroa vacciniforme. All patients tested positive for high serum EBV DNA load (>5 × 10 SP 5 sp copies/ml). EBV viral capsid antigen (VCA) IgG antibodies were positive but IgM antibodies negative, suggesting chronic active EBV infection. [Extracted from the article]

Summary: Congestion detection in transmission control protocol/active queue management networks remains a challenging problem in which the choosing of congestion signal is one of the most important factors. Exponentially weighted moving average of queue length, the most widely used congestion signal, is facing difficulties in detecting incipient congestion and quantifying the optimal forgetting factor. Aiming at these 2 disadvantages, we propose an average queue‐length‐difference–based congestion detection algorithm where exponentially weighted moving average of queue‐length difference is chosen as the congestion signal with the theoretical optimal forgetting factor deduced. First, by defining the queue‐length difference as the state, the corresponding state equation is derived from the fluid model. Second, we prove that the inflow traffic in state equation is a discrete‐time martingale, which can be transformed to a Wiener process according to the martingale representation theorem. Noticing that the observation of state will be coupled with noise because of the unstable transmission, the state estimation is then derived with the application of recursive least squares filter. The filter gain of state estimation, which is a function of the noise‐signal ratio, corresponds to the optimal forgetting factor in average queue‐length‐difference–based congestion detection algorithm. Simulation results in NS‐3 and MATLAB illustrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Abstract: The terminal‐selective, remote C(sp3)−H alkylation of alkenes was achieved by a relay process combining NiH‐catalyzed hydrometalation, chain walking, and alkylation. This method enables the construction of unfunctionalized C(sp3)−C(sp3) bonds under mild conditions from two simple feedstock chemicals, namely olefins and alkyl halides. The practical value of this transformation is further demonstrated by the large‐scale and regioconvergent alkylation of isomeric mixtures of olefins at low catalyst loadings. [ABSTRACT FROM AUTHOR]

Abstract: The terminal‐selective, remote C(sp3)−H alkylation of alkenes was achieved by a relay process combining NiH‐catalyzed hydrometalation, chain walking, and alkylation. This method enables the construction of unfunctionalized C(sp3)−C(sp3) bonds under mild conditions from two simple feedstock chemicals, namely olefins and alkyl halides. The practical value of this transformation is further demonstrated by the large‐scale and regioconvergent alkylation of isomeric mixtures of olefins at low catalyst loadings. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The FokI polymorphism (C>T, rs2228570) of the vitamin D receptor gene is a coding nonsynonymous single nucleotide polymorphism in the translational initiation codon reported to have functional significance. Although the role of rs2228570 in the risk of ovarian cancer has been widely researched, the association is still unclear. We performed an updated meta‐analysis to clarify this issue. Methods: Eligible studies were retrieved from electronic databases for the period 2007–2016. The association was measured by unadjusted odds ratio combined with 95% confidence intervals (CIs). Random‐effect or fixed‐effect models were used according to the heterogeneity of the studies. We further appreciated the strength of evidence according to Venice guidance. Results: Fourteen studies (4448 cases and 7242 controls) were included in the meta‐analysis. Studies were predominantly conducted in Caucasian populations (4152 cases and 6693 controls). A dominant genetic model was determined to be the most appropriate genetic model. Overall meta‐analysis showed a fixed‐effect odds ratio of 1.14 (95% CI 1.05–1.23) under a dominant model. The fixed‐effect odds ratios were 1.12 (95% CI 1.03–1.21) and 1.49 (95% CI 1.06–2.09) in Caucasian and Asian populations, respectively. The strength of the evidence was moderate. Conclusion: The rs2228570 polymorphism increased the risk of ovarian cancer in Caucasian populations in a dominant genetic model. The role of this polymorphism in the risk of ovarian cancer in Asian populations should be further studied. [ABSTRACT FROM AUTHOR]

Background Conventional cohort studies have consistently shown that exposure to maternal smoking in pregnancy is associated with about twice the risk of attention deficit hyperactivity disorder (ADHD) in the offspring. However, recent studies using alternative designs to disentangle the effect of social and genetic confounders have suggested that confounding may account for the association. In this study we aimed to estimate the association by a sibling design. Methods We used a design with half and full siblings in a Danish national register-based cohort on all singletons born between January 1991 and December 2006 and followed until January 2011. Data were available for 90% ( N = 968,665) of the singleton live births in the period. We used the combination of the International Classification of Diseases (10th version) diagnosis of hyperkinetic disorder (HKD) and ADHD medication to identify children. We used sibling-matched (conditional) Cox regression to control social and genetic confounding. Results Using conventional cohort analyses, we found the expected association between pregnancy smoking and offspring ADHD (adjusted HR 2.01, 95% CI 1.94-2.07). In the sibling analysis, however, we did not detect such a strong association (adjusted HR 1.07, 95% CI 0.94-1.22). There was no difference between results for half- and full sibling analyses. The link between pregnancy smoking and low birth weight remained robust in the sibling design (adjusted OR 1.68, 95% CI 1.33-2.12). Conclusions We found no support for prenatal smoking as a strong causal factor in ADHD. Our findings suggest that the strong association found in most previous epidemiological studies is likely to be due to a strong link between maternal smoking and maternal ADHD genetics or shared family environment. Pregnant women should still be encouraged to stop smoking because of other risks, but we have no reason to believe that this would reduce the risk of ADHD in the offspring. [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]

Background and Aim There are a multitude of cross-sectional surveys that provide the prevalence of irritable bowel syndrome ( IBS) in the community. However, the data regarding the influence of socioeconomic status on prevalence of IBS were sparse. This study is to investigate the possible relation between human development and prevalence of IBS, at national level. Methods EMBASE Classic, EMBASE, and MEDLINE were searched (until October 2013) to identify population-based studies that reported prevalence of IBS. Human Development Index ( HDI) was chosen to assess socioeconomic status at national level. Results Firstly, no correlation was observed between prevalence of IBS and national HDI ( P = 0.848). Specifically, there was no statistical significance in prevalence between developing and developed countries ( P = 0.319). Moreover, prevalence of IBS failed to witness a downtrend in worldwide over the past two decades. Interestingly, the ratio of female/male prevalence was correlated with national HDI according to linear regression analysis ( r = 0.395), and the ratio in the developing was significant lower than that in the developed ( P = 0.0394). Lastly, except methods of data collection ( P < 0.000), it shows no difference between developing and developed countries in diagnostic criteria, IBS subtypes, and age distribution ( P = 0.119, 0.327, and 0.845 respectively). Conclusions This study is the first time to investigate the relation between IBS prevalence and national socioeconomic status, with consideration of years, gender, and other factors. It demonstrates that national development is not a direct indicator for prevalence of IBS. [ABSTRACT FROM AUTHOR]

Nitro‐charged activation: An organocatalytic enantioselective conjugate addition of aryl methyl nucleophiles to enals has been developed to produce ubiquitous chiral benzylic building blocks (see scheme; TES=triethylsilyl). Taking advantage of the strongly electron‐withdrawing nature of nitro groups, which can be conveniently transformed into other functionalities, this functionality was incorporated into aromatic systems as a temporary activating group. [ABSTRACT FROM AUTHOR]

Aims Mesenchyme forkhead 1 ( Fox C2) is an epithelial-mesenchymal transition ( EMT)-inducing factor. Previous studies have demonstrated that Fox C2 binds directly to the promoter region of p120-catenin (p120ctn). The aim of this study was to investigate the clinical significance of Fox C2 expression and the inter-relationship between Fox C2 and p120ctn, in gastric cancer. Methods and results Immunohistochemistry was used to examine the expression of Fox C2 and p120ctn proteins in 325 gastric cancer samples. Staining for Fox C2 in cancer tissues was markedly stronger than in normal tissues. High Fox C2 expression was associated significantly with differentiation, invasion depth, lymph node metastasis and tumour stage. Patients with high Fox C2 expression or low p120ctn expression had a poor prognosis. In the high p120ctn expression group, the prognosis for patients with low Fox C2 expression was better than for the high Fox C2 group. Moreover, stepwise Cox regression showed that p120ctn was an independent prognostic factor, but Fox C2 in combination with p120ctn was not correlated significantly with survival. Conclusions We found that Fox C2 and p120ctn play important roles in the progression and prognosis of gastric cancer. Moreover, Fox C2 and p120ctn should be evaluated further as novel biomarkers and therapeutic targets for gastric cancer treatment. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To quantify the demographic characteristics, symptoms, and outcomes of women with abdominal wall endometriosis (AWE) in order to identify the optimal treatment and prevention techniques for AWE in the Chinese population. Methods: In a retrospective study, women diagnosed with AWE at the Gynecology Hospital of Fudan University, Shanghai, China, between January 2003 and December 2011 were identified from the hospital''s medical records. Data on patient age, previous surgeries, symptoms, asymptomatic time interval, duration of complaints, mass location, size, tenderness, diagnosis, treatment, and recurrence were analyzed. Results: During the study period, 229 women were diagnosed with AWE, and histopathologic confirmation was obtained for 227 women (mean age, 31.7±3.8years). Each of these patients had undergone previous surgery, and 14 had undergone resection for AWE. The primary symptoms were pain, either cyclical (65.2%) or noncyclical (27.3%), and presence of a mass (84.1%; mean diameter, 2.9±1.3cm). The mean time interval between previous surgery and onset of symptoms was 2.3±2.2years. For all patients, the abdominal mass was surgically excised. The postoperative recurrence rate was 1.5%. Conclusion: Complete resection is the primary treatment for AWE. A combination of surgical re-excision and postoperative adjuvant medical therapy is recommended for patients with recurrent AWE. [Copyright &y& Elsevier]

Background: Studies suggest that children born very preterm have a high risk of developmental coordination disorder (DCD). We examined the relation between the larger spectrum of gestational age at birth and the risk of DCD. Methods: We used the 7-year follow-up data from 22898 singletons in the Danish National Birth Cohort. We calculated a total score from the Developmental Coordination Disorder Questionnaire (DCDQ), incorporated in the 7-year follow-up, and defined children with a score of 46 or below as having probable DCD. Information on gestational age was obtained from the Medical Birth Register. Results: Gestational age at birth was inversely associated with the risk of DCD; a decline in gestational age by a week was associated with a 19% [95% confidence interval 14%, 25%] increased risk of DCD screening positive among children delivered before 40 weeks. No significant increased risk of DCD was seen for children born post-term. Conclusion: Our data indicate that short gestational age at birth in a range up to gestational week 37 is related to an increased risk of DCD. [ABSTRACT FROM AUTHOR]

The crystal structure of the 11.14 kDa orphan ORF 1382 from Archaeoglobus fulgidus (AF1382) has been determined by sulfur SAD phasing using a moderately diffracting crystal and 1.9 Å wavelength synchrotron X-rays. AF1382 was selected as a structural genomics target by the Southeast Collaboratory for Structural Genomics (SECSG) since sequence analyses showed that it did not belong to the Pfam-A database and thus could represent a novel fold. The structure was determined by exploiting longer wavelength X-rays and data redundancy to increase the anomalous signal in the data. AF1382 is a 95-residue protein containing five S atoms associated with four methionine residues and a single cysteine residue that yields a calculated Bijvoet ratio (Δ Fanom/ F) of 1.39% for 1.9 Å wavelength X-rays. Coupled with an average Bijvoet redundancy of 25 (two 360° data sets), this produced an excellent electron-density map that allowed 69 of the 95 residues to be automatically fitted. The S-SAD model was then manually completed and refined ( R = 23.2%, Rfree = 26.8%) to 2.3 Å resolution (PDB entry 3o3k). High-resolution data were subsequently collected from a better diffracting crystal using 0.97 Å wavelength synchrotron X-rays and the S-SAD model was refined ( R = 17.9%, Rfree = 21.4%) to 1.85 Å resolution (PDB entry 3ov8). AF1382 has a winged-helix-turn-helix structure common to many DNA-binding proteins and most closely resembles the N-terminal domain (residues 1-82) of the Rio2 kinase from A. fulgidus, which has been shown to bind DNA, and a number of MarR-family transcriptional regulators, suggesting a similar DNA-binding function for AF1382. The analysis also points out the advantage gained from carrying out data reduction and structure determination on-site while the crystal is still available for further data collection. [ABSTRACT FROM AUTHOR]

The article reports a study which examined whether the onset of rheumatoid arthritis (RA) in women before conception affects the time to pregnancy (TTP). It mentions that the study evaluated pregnant women who enrolled in the Danish National Birth Cohort between 1996 and 2002, and used the Danish National Hospital Discharge Registry to identify women with RA. Details pertaining to the methods, data analysis and study results are also presented.

ABSTRACT Objective. Increasing use of infertility treatment and a decline in demographic fertility in some countries have raised concern whether human fecundity is declining or has declined over time. A dramatic decline in semen quality over the past half-century has been proposed and widely discussed, but none of the existing studies provide data good enough for coming to any firm conclusion. Results. Results from 19 articles published during the last 5 years on semen quality and fecundity, covering data from the Nordic countries since the year 2000, do not indicate an ongoing decline in fertility. Conclusion. We will probably never know, whether semen quality and fecundity has declined over time, but we may be able to monitor biological fecundity and semen quality over time from now on. There are both research initiatives and interest from official channels that could provide more funding for infertility research. [ABSTRACT FROM AUTHOR]

Babies born of infertile couples, regardless of treatment, have a higher risk of preterm birth and low birthweight, conditions associated with delayed development. We examined developmental milestones in singletons as a function of parental infertility [time to pregnancy (TTP) > 12 months] and infertility treatment. From the Danish National Birth Cohort (1997-2003), we identified 37 897 singletons born of fertile couples (TTP < or = 12 months), 4351 born of infertile couples conceiving naturally (TTP > 12 months), and 3309 born after infertility treatment. When the children were about 18 months old, mothers reported 12 developmental milestones by responding to structured questions. We defined a failure to achieve the assessed milestone or the minimal numbers of milestones in a summary (motor, or cognitive/language skills) as delay. Naturally conceived children born of infertile couples had a pattern of psychomotor development similar to that of children born of fertile couples, but increasing TTP correlated with a modest delay. When the analysis was restricted to infertile couples (treated and untreated), children born after treatment showed a slight delay in cognitive/language development (odds ratio 1.24, [95% confidence interval 1.01, 1.53]) for not meeting at least three out of six cognitive/language milestones); children born after intracytoplasmic sperm injection (ICSI) had the highest estimated relative risk of delay for most milestones, especially motor milestones. These results suggest that a long TTP may be associated with a modest developmental delay. Infertility treatment, especially ICSI, may be associated with a slight delay for some of these early milestones. [ABSTRACT FROM AUTHOR]

Abstract: Our previous study demonstrated that NYD-SP27 is a novel inhibitory PLC isoform expressed endogenously in human pancreas and upregulated in CFPAC-1 cells. The present study investigated the effect of NYD-SP27 down-regulation on the ATP-stimulated and Ca2+-dpendent pancreatic anion secretion by CFPAC-1 cell line using short-circuit current (I SC) recording. NYD-SP27 antisense-transfected CFPAC-1 (AT-CF) cells exhibited a significantly higher basal transmembrane potential difference and current than those of empty vector-transfected CFPAC-1 (VT-CF) cells. Cl− channel blocker, DPC or Glibenclamide (1mM), and inhibitor of Na+-K+-Cl− cotransporter, bumetanide (100μM) significantly inhibited the basal current in AT-CF cells. The inhibitor of adenylate cyclase, MDL12330A (20μM), and Ca2+-dependent Cl− channel (CaCC) blocker, DIDS (100μM) also significantly reduced the basal current in AT-CF. Apical application of ATP (10μM) stimulated a fast transient I SC increase in VT-CF cells, but a more sustained rise with slower decline in AT-CF cells. Pretreatment with BAPTA-AM (50μM) reduced the ATP-induced I SC response in AT-CF cells by 77.9%. PMA (1μM), a PKC activator, inhibited the ATP-stimulated current increase (the transient peak) in VT-CF cells, but had no effect on the AT-CF cells. However, PKC inhibitor, staurosporine (40μM) could inhibit the ATP-induced I SC response in AT-CF cells. The present results confirm the previously proposed inhibitory role of NYD-SP27 in the PLC pathway and demonstrate that the suppression of its expression could result in an enhancement of ATP-stimulated Ca2+ dependent pancreatic anion secretion. [Copyright &y& Elsevier]

Abstract: In the present study we investigated the role of Ca2+ in tetramethylpyrazine (TMP)-induced anion secretion in the human colonic epithelial cell line, Caco-2, using the short-circuit current (I SC) technique in conjunction with intracellular Ca2+ measurements. The results showed that TMP-induced I SC response was significantly reduced by 58.8% and 38.3% after inhibiting Ca2+ ATPase of endoplasmic reticulum (ER) with thapsigargin and mobilizing ER stored Ca2+ release with ATP, respectively. Conversely, thapsigargin- and ATP-evoked I SC responses were also significantly reduced by pretreatment with TMP by 43.2% and 38.5%, respectively. Conversely, removal of extracellular Ca2+, apical but not basolateral, or the presence of the Ca2+ chelator (EGTA) significantly increased TMP-induced I SC by 47.1% and 37.8%, respectively. Similar to TMP, thapsigargin-induced current increase was also enhanced by chelating extracellular Ca2+ or in Ca2+ free solution; however, removal of extracellular Ca2+ did not significantly affect 3-isobutyl-1-methylxanthine (IBMX)- and forskolin-induced transepithelial current. Measurement of the intracellular concentration of free Ca2+ ([Ca2+]i) with fura-2/AM showed that TMP could induce an increase in [Ca2+]i but pretreatment with TMP significantly reduced thapsigargin-evoked, but not ATP-induced, [Ca2+]i increase. These results suggest that the effect of TMP on colonic anion secretion is partly mediated by TMP-increased [Ca2+]i by acting on a target similar to thapsigargin. The observed inhibitory effect of extracellular Ca2+ on Ca2+-dependent anion secretion represents a novel mechanism by which Ca2+-dependent regulation of epithelial electrolyte transport may be fine-tuned by extracellular Ca2+ in the apical domain. [Copyright &y& Elsevier]

The present study examined the effect of Bak Foong Pills (BFP), an over-the-counter traditional Chinese medicine (China registration no. Z980035), on anion secretion and the underlying signaling pathways in normal and cystic fibrosis pancreatic duct cell lines, CAPAN-1 and CFPAC-1, respectively, using the short-circuit current technique. Apical addition of BFP ethanol extract (600 μg/ml) induced a fast transient ISC peak that was followed by a slower but more sustained increase in ISC in CAPAN-1 cells. However, the response to BFP in CFPAC-1 was predominantly the first transient peak. Apical addition of DIDS (200 μM) inhibited the first peak by more than 60% in both cell lines without significantly affecting the second ISC rise. More than 85% of the BFP-induced first transient in both cell lines was inhibited when extra and intracellular Ca2+ was chelated or emptied by pre-treatment with BAPTA (100 μM) and thapsigargin (10 μM), respectively. Acute addition of PMA (1 μM), a PKC activator, blocked more than 95% of the BFP-induced first peak in both cell lines, consistent with previously reported PKC modulation of Ca2+-dependent pancreatic anion secretion. The BFP-induced second ISC rise in CAPAN-1 could be inhibited by 73.6% and 71.13% by pretreatment of the cells with MDL-12330A (20 μM), an adenylate cyclase inhibitor and Rp-cAMP (200 μM), a cyclic AMP antagonist, respectively. However, less than 25% of the ISC was inhibited by combined treatment with BAPTA and thapsigargin. The second rise was also completely blocked by DPC (2 mM) or Glibenclamide (1 mM). The results indicate that BFP ethanol extract stimulates pancreatic duct anion secretion in normal and CF cells via different signaling pathways involving both Ca2+ and cAMP. [Copyright &y& Elsevier]

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]

Circular RNA (circRNA) have been found to play an important role in the progression of many diseases, including interstitial cystitis (IC). However, the role of circTHBS1 in IC progression is still unclear. Exploring the role and potential molecular mechanism of circTHBS1 in the development of IC. The enzyme‐linked immunosorbent assay was used to assess the levels of inflammatory cytokines. The expression levels of circTHBS1, microRNA (miR)‐139‐5p, and mitofusin 2 (MFN2) were evaluated using quantitative real‐time PCR. Cell proliferation and migration were determined using MTT assay, Edu staining, and transwell assay. The protein levels of epithelial‐mesenchymal transition (EMT) markers and MFN2 were examined using western blot analysis. The relationship between miR‐139‐5p and circTHBS1 or MFN2 was confirmed using the dual‐luciferase reporter assay and RIP assay. CircTHBS1 was highly repressed in IC tissues and cells, and its expression was positively correlated with the inflammatory response of IC patients. CircTHBS1 could promote the proliferation, migration, EMT process, and inflammation of IC cells, while its knockdown had an opposite effect. CircTHBS1 could serve as a sponge of miR‐139‐5p, and miR‐139‐5p could participate in the regulation of circTHBS1 on IC cell progression. In addition, miR‐139‐5p could target MFN2, and it could inhibit the progression of IC cells by targeting MFN2. Furthermore, circTHBS1 sponged miR‐139‐5p to positively regulate MFN2. CircTHBS1 promoted IC cell proliferation, migration, EMT process, and inflammation by regulating the miR‐139‐5p/MFN2 axis indicating that circTHBS1 might be a potential target for IC treatment. [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]

Although copper‐nitrene has been extensively studied as a versatile active species in various transformations, asymmetric reactions involving copper‐nitrene have been limited to the aziridination of olefins. Herein, we report the novel copper‐nitrene‐catalyzed desymmetric oxaziridination reaction of cyclic diketones with alkyl azides and the subsequent rearrangement of the resulting highly active intermediate, which produces a synthetically challenging chiral bicyclic lactam containing a quaternary carbon center. This procedure not only enriches the copper‐nitrene‐catalyzed asymmetric reactions, but also provides an alternative strategy to address the inherent challenges of catalytic asymmetric Schmidt reactions. This unique reaction could inspire the investigation of novel copper‐nitrene‐catalyzed asymmetric transformations and their reaction mechanisms. [ABSTRACT FROM AUTHOR]

Although copper‐nitrene has been extensively studied as a versatile active species in various transformations, asymmetric reactions involving copper‐nitrene have been limited to the aziridination of olefins. Herein, we report the novel copper‐nitrene‐catalyzed desymmetric oxaziridination reaction of cyclic diketones with alkyl azides and the subsequent rearrangement of the resulting highly active intermediate, which produces a synthetically challenging chiral bicyclic lactam containing a quaternary carbon center. This procedure not only enriches the copper‐nitrene‐catalyzed asymmetric reactions, but also provides an alternative strategy to address the inherent challenges of catalytic asymmetric Schmidt reactions. This unique reaction could inspire the investigation of novel copper‐nitrene‐catalyzed asymmetric transformations and their reaction mechanisms. [ABSTRACT FROM AUTHOR]

Enhanced red emissive carbon dots (CDs) and their enrichment in spheres are ideal for sensing applications. Here, we propose a novel strategy for enhancing the red emission of CDs and enriching it in dendritic SiO2 nanospheres. The surface carboxylated and red emissive CDs obtained by alkali/acid treatment of blue emissive CDs are dissolved in N‐β‐(aminoethyl)‐γ‐aminopropyltrimethoxysilane for silanization. Electron injection and long chain passivation greatly enhance the red emission of CDs. Through the reaction of silane with the hydroxyl groups of dendritic SiO2 spheres, the silanized CDs can be enriched in dendritic SiO2 spheres. Encapsulation of composite spheres with (3‐Aminopropyl)‐trimethoxysilane protects CDs and facilitates bioconjugation. These fluorescence SiO2 spheres exhibit high quantum yields in red emission (48.5 % for aqueous solution and 35.7 % for solid state) and maintain good monodispersity. It is further used as a signal of lateral flow test strips to target Zika virus, and demonstrates an ultra‐sensitive, specific and effective immunoassay. And considerable results have been achieved in the analysis of actual samples. [ABSTRACT FROM AUTHOR]