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Proton exchange membrane (PEM) electrolysis holds great promise for green hydrogen production, but suffering from high loading of platinum‐group metals (PGM) for large‐scale deployment. Anchoring PGM‐based materials on supports can not only improve the atomic utilization of active sites but also enhance the intrinsic activity. However, in practical PEM electrolysis, it is still challenging to mediate hydrogen adsorption/desorption pathways with high coverage of hydrogen intermediates over catalyst surface. Here, operando generated stable palladium (Pd) hydride nanoclusters anchored on tungsten carbide (WCx) supports were constructed for hydrogen evolution in PEM electrolysis. Under PEM operando conditions, hydrogen intercalation induces formation of Pd hydrides (PdHx) featuring weakened hydrogen binding energy (HBE), thus triggering reverse hydrogen spillover from WCx (strong HBE) supports to PdHx sites, which have been evidenced by operando characterizations, electrochemical results and theoretical studies. This PdHx‐WCx material can be directly utilized as cathode electrocatalysts in PEM electrolysis with ultralow Pd loading of 0.022 mg cm−2, delivering the current density of 1 A cm−2 at the cell voltage of ~1.66 V and continuously running for 200 hours without obvious degradation. This innovative strategy via tuning the operando characteristics to mediate reverse hydrogen spillover provide new insights for designing high‐performance supported PGM‐based electrocatalysts. [ABSTRACT FROM AUTHOR]

Atropisomerism, an expression of axial chirality caused by limited bond rotation, is a prominent aspect within the field of medicinal chemistry. It has been shown that atropisomers of a wide range of compounds, including established FDA‐approved drugs and experimental molecules, display markedly different biological activities. The time‐dependent reversal of chirality in atropisomers poses complexity and obstacles in the process of drug discovery and development. Nonetheless, recent progress in understanding atropisomerism and enhanced characterization methods have greatly assisted medicinal chemists in the effective development of atropisomeric drug molecules. This article provides a comprehensive review of their special design thoughts, synthetic routes, and biological activities, serving as a reference for the synthesis and biological evaluation of bioactive atropisomers in the future. [ABSTRACT FROM AUTHOR]

Azomethine imines, as a prominent class of 1,3‐dipolar species, hold great significance and potential in organic and medicinal chemistry. However, the reported synthesis of centrally chiral azomethine imines relies on kinetic resolution, and the construction of axially chiral azomethine imines remains unexplored. Herein, we present the synthesis of axially chiral azomethine imines through copper‐ or chiral phosphoric acid catalyzed ring‐closure reactions of N′‐(2‐alkynylbenzylidene)hydrazides, showcasing high efficiency, mild conditions, broad substrate scope, and excellent enantioselectivity. Furthermore, the biological evaluation revealed that the synthesized axially chiral azomethine imines effectively protect dorsal root ganglia (DRG) neurons by inhibiting apoptosis induced by oxaliplatin, offering a promising therapeutic approach for chemotherapy‐induced peripheral neuropathy (CIPN). Remarkably, the (S)‐ and (R)‐atropisomers displayed distinct neuroprotective activities, underscoring the significance of axial stereochemistry. [ABSTRACT FROM AUTHOR]

Tendons are an important part of the musculoskeletal system. Connecting muscles to bones, tendons convert force into movement. Tendon injury can be acute or chronic. Noticeably, tendon healing requires a long time span and includes inflammation, proliferation, and remodeling processes. The mismatch between endogenous and exogenous healing may lead to adhesion causing further negative effects. Management of tendon injuries and complications such as subsequent adhesion formation are still challenges for clinicians. Due to numerous factors, tendon healing is a complex process. This review introduces the role of various biological and mechanical factors and epigenetic regulation processes involved in tendon healing. [ABSTRACT FROM AUTHOR]

An asymmetric synthesis of a series of tricycle‐fused dispirooxindoles frameworks assembled in different rings was disclosed via multicomponent cascade 1,3‐dipolar cycloadditions of electron‐deficient 2‐pyrones and trifluoroethylisatin ketimines under the catalysis of hydroquinine or (DHQD)2PHAL with 61→99% ee and >19:1 dr. Meanwhile, these potentially biologically important dispirooxindoles fused pyrrolidinyl/tetrahydropyranone/pyrrolidinyl frame‐works bear eight contiguous stereocenters and functionalized pharmacophores which could further transfer to linaer dispirooxindoles and spirooxindoles bearing epoxyethyl moiety with retentive enantioselectivity. [ABSTRACT FROM AUTHOR]

Aim: Effective control of invasive species and conservation of native biodiversity requires accurate species identification. Several species of apple snails (Ampullariidae: Pomacea) from South America have become widespread pests in Asia since their introduction in the early 1980s, but their taxonomic uncertainty has hindered our understanding of the invasive processes. We aim to determine the identity and distribution of Pomacea species in Hong Kong, which has been known as a stepping stone of species invasion. Location: Hong Kong. Methods: We collected 162 apple snails from five freshwater wetlands of Hong Kong, sequenced the mitochondrial COI, genotyped the nuclear EF1α and built a COI dataset of 1378 sequences of apple snails from mainland China, Malaysia, Argentina and Brazil. We identified the species, determine the introgression pattern and analysed their population structures. Results: We found the co‐occurrence of P. canaliculata, P. maculata and P. occulta in Hong Kong for the first time. Pomacea canaliculata represented the dominant species (85% of collected specimens). The three Pomacea species from Hong Kong had low genetic diversity. High genetic similarity existed between P. canaliculata populations of Hong Kong and Malaysia, P. occulta populations of Hong Kong and mainland China and P. maculata populations of mainland China and Malaysia. Our samples contained a high proportion of hybrids. Main conclusions: Apple snails may have been introduced into Hong Kong multiple times: both P. canaliculata and P. occulta likely came from Argentina; P. maculata came from both Argentina and Brazil. Genetic drift largely explains the differentiation of Pomacea spp. among regions. Introgressive hybridization may have contributed to population fitness by increasing genetic variation to neutralize the founder effect. The knowledge on species identity, distribution and genetic diversity of apple snails from this study will contribute to better understanding their invasive mechanisms and prevention of their continued spread in Asia. [ABSTRACT FROM AUTHOR]

Inducible gene‐expression systems play important roles in gene functional assays in the post‐genome era. Streptomyces phage‐derived phiC31 integrase, which mediates an irreversible site‐specific cassette exchange between the phage attachment site (attP) and the bacterial attachment site (attB), provides a promising option for the construction of a controllable gene‐expression system. Here, we report a phiC31 integrase‐mediated promoter flip system (FLIP) for the inducible expression of target genes in silkworm (Bombyx mori). First, we constructed a FLIP reporter system, in which a BmAct4 promoter with enhanced translational efficiency was flanked by the attB and attP sites in a head‐to‐head orientation and further linked in a reverse orientation to a DsRed reporter gene. The coexpression of a C‐terminal modified phiC31‐NLS integrase carrying a simian virus 40 (SV40) nuclear localization signal (NLS) effectively flipped the BmAct4 promoter through an attB/attP exchange, thereby activating the downstream expression of DsRed in a silkworm embryo‐derived cell line, BmE. Subsequently, the FLIP system, together with a system continuously expressing the phiC31‐NLS integrase, was used to construct binary transgenic silkworm lines. Hybridization between FLIP and phiC31‐NLS transgenic silkworm lines resulted in the successful flipping of the BmAct4 promoter, with an approximately 39% heritable transformation efficiency in silkworm offspring, leading to the constitutive and high‐level expression of DsRed in silkworms, which accounted for approximately 0.81% of the silkworm pupal weight. Our successful development of the FLIP system offers an effective alternative for manipulating gene expression in silkworms and other lepidopteran species. [ABSTRACT FROM AUTHOR]

The cover image is based on the article Bioactive atropisomers: Unraveling design strategies and synthetic routes for drug discovery by Shuai‐Jiang Liu et al., https://doi.org/10.1002/med.22037..By Shuai‐Jiang Liu; Qian Zhao; Xiao‐Chen Liu; Allan B. Gamble; Wei Huang; Qian‐Qian Yang and Bo HanReported by Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

BACKGROUND Apple snails from the genus Pomacea have spread widely in paddy fields and other wetlands of southern China since their introduction in the 1980s. Pomacea spp. are commonly identified using mitochondrial COI sequences. However, sequencing the nuclear elongation factor 1‐alpha (EF1α) gene revealed genetic introgression between field populations of P. canaliculata and P. maculata, which produce surviving hybrids in laboratory crossbreeding experiments. RESULTS: In this study, we sequenced 1054 EF1α clones to design specific primers and established a fast and accurate multiplex polymerase chain reaction (PCR) method for genotyping EF1α. Combined with genotyping P. canaliculata and P. maculata based on mitochondrial COI and nuclear EF1α, we revealed the genetic introgression patterns of 30 apple snail populations in China. Purebred and hybrid individuals of P. canaliculata were widely distributed, while pure maculata‐EF1α type was detected only in a few individuals identified as P. canaliculata based on COI sequences. Each egg clutch had one to three genetic patterns, indicating multiple paternity or segregation in the progeny of hybrids. The higher percentages of hybrids in both wild populations and progeny than the homozygotes indicated a potential heterosis in the apple snail populations. Additionally, egg size and clutch size of the apple snails became homogeneous among the non‐native populations exhibiting introgression hybridization. CONCLUSION: Our findings emphasize the value of apple snails as a model to study the mechanisms and impacts of introgressive hybridization on fitness traits. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Objectives: Preoperative fasting, water deprivation, and intraoperative fluid loss and redistribution result in hypovolemia in patients undergoing surgery. Some findings have indicated that the superior vena cava (SVC) diameter and variation, as determined by transesophageal echocardiography during surgery, do not reflect central venous pressure effectively. This study aimed to compare and correlate the SVC diameter and variation with the stroke volume variation for predicting fluid responsiveness in patients undergoing invasive positive pressure ventilation. Methods: Thirty‐six patients scheduled for elective gastrointestinal surgery under general anesthesia with invasive positive pressure ventilation were included in this study. After anesthesia induction, the stroke volume variation, SVC diameter, mean arterial pressure, central venous pressure, and pulse were recorded, and measurements after fluid challenge were recorded as well. The SVC variation was calculated before and after the fluid challenge. Results: After the fluid challenge, the SVC diameter markedly increased, whereas the SVC variation and stroke volume variation significantly decreased (P < .05). The optimal cutoff value for the SVC variation was 21.1%, and the area under the curve (AUC) from a receiver operating characteristic curve analysis was 0.849. The optimal cutoff value for the minimal SVC diameter was 1.135 cm, and that AUC was 0.929. In addition, the optimal cutoff value for the maximal SVC diameter was 1.480 cm, and the AUC was 0.862. Conclusions: The minimal SVC diameter may be an effective indicator for predicting fluid responsiveness in patients undergoing invasive positive pressure ventilation. [ABSTRACT FROM AUTHOR]

This article, published in Angewandte Chemie International Edition, discusses the efficient construction of axially chiral azomethine imines through Cu- or chiral phosphoric acid (CPA)-catalyzed ring-closures of N'- (2-alkynylbenzylidene)hydrazides. The authors, Bo Han, Gu Zhan, Bo Liu, et al., conducted biological studies that revealed the (S)-atropisomer product effectively protects dorsal root ganglia (DRG) neurons by inhibiting oxaliplatin-induced apoptosis, while the (R)-atropisomer lacks protective effects. This research provides valuable insights into the synthesis and potential neuroprotective activity of these compounds. [Extracted from the article]

This article, published in Angewandte Chemie, discusses the efficient construction of axially chiral azomethine imines through Cu- or chiral phosphoric acid (CPA)-catalyzed ring-closures of N'- (2-alkynylbenzylidene)hydrazides. The authors, Bo Han, Gu Zhan, Bo Liu, et al., conducted biological studies that revealed the (S)-atropisomer product effectively protects dorsal root ganglia (DRG) neurons by inhibiting oxaliplatin-induced apoptosis, while the (R)-atropisomer lacks protective effects. This research provides valuable insights into the synthesis and potential neuroprotective activity of these compounds. [Extracted from the article]

Abstract: An asymmetric four‐component [5+1+1+1] formal cycloaddition reaction of 3‐substituted 2‐cyclopentenones, activated methylene nucleophiles and two molecules of aldehydes is developed under chiral primary aminocatalysis, producing a diversity of highly enantioenriched fused and spirocyclic frameworks with high molecular complexity. Mechanism studies indicate that the current reaction proceeds in a challenging cascade quintuple Knoevenagel condensation/Michael addition/retro‐Michael addition/Michael addition/Michael addition sequence via diverse aminocatalytic modes. [ABSTRACT FROM AUTHOR]

ABSTRACT. As it is extremely difficult to make DNA transformation for the obligate fungus, Blumeria graminis f. sp. tritici ( Bgt), we developed a heterologous expression system for characterization of a Bgt gene, CYP51, which encodes 14α-demethylase. The CYP51 gene from Bgt was transformed into the necrotrophic fungus, Botrytis cinerea. Reverse transcription polymerase chain reaction showed that the Bgt CYP51 was transcribed in B. cinerea. Green fluorescence was observed in the transformants of B. cinerea carrying the Bgt CYP51-GFP fusion cassette, suggesting that its translation was successful. Fungicide sensitivity tests revealed that B. cinerea transformed with Bgt CYP51 showed reduced sensitivity to a sterol demethylation inhibitor triadimefon, but not to a benzimidazole fungicide carbendazim. These results indicated that this heterologous expression system can be used for functional analysis of other Bgt genes. [ABSTRACT FROM AUTHOR]