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Summary Many biotic or abiotic factors such as CPPU (N‐(2‐chloro‐pyridin‐4‐yl)‐N′‐phenylurea), a growth regulator of numerous crops, can induce bitterness in cucurbits. In melon, cucurbitacin B is the major compound leading to bitterness. However, the molecular mechanism underlying CuB biosynthesis in response to different conditions remains unclear. Here, we identified a set of genes involved in CPPU‐induced CuB biosynthesis in melon fruit and proposed CmBr gene as the major regulator. Using CRISPR/Cas9 gene editing, we confirmed CmBr's role in regulating CuB biosynthesis under CPPU treatment. We further discovered a CPPU‐induced MYB‐related transcription factor, CmRSM1, which specifically binds to the Myb motif within the CmBr promoter and activates its expression. Moreover, we developed an introgression line by introducing the mutated Cmbr gene into an elite variety and eliminated CPPU‐induced bitterness, demonstrating its potential application in breeding. This study offers a valuable tool for breeding high‐quality non‐bitter melon varieties and provides new insights into the regulation of secondary metabolites under environmental stresses. [ABSTRACT FROM AUTHOR]

Background: Depression is a serious mental disorder and the most prevalent cause of disability and suicide worldwide. Chronic unpredictable mild stress (CUMS) can lead to a significant acceleration of depression development. Quercetin (Que) is a flavonoid compound with a wide range of pharmacological effects. Recent studies have shown that quercetin can improve CUMS‐induced depression‐like behavior, but the mechanism of its improvement is still unclear. α2δ‐1 is a regulatory subunit of voltage‐gated calcium channel, which can interact with N‐methyl‐D‐aspartate receptor (NMDAR) to form a complex. Objective: In this study, we found that Que could inhibit the increase of α2δ‐1 and NMDAR expression in rat hypothalamus induced by CUMS. In pain, chronic hypertension and other studies have shown that α2δ‐1 interacts with the NMDAR to form a complex, which subsequently affects the expression level of NMDAR. Consequently, the present study aimed to investigate the antidepressant effect of Que in vivo and in vitro and to explore its mechanism of action in terms of the interaction between α2δ‐1 and NMDAR. Methods: Rats were randomly exposed to two stressors every day for 4 weeks to establish a CUMS rat model, then sucrose preference test (SPT), forced swimming test (FST), tail suspension test (TST), and open field test (OFT) were performed to detect the behavior of CUMS rats, so as to evaluate whether the CUMS rat model was successfully established and the improvement effect of Que on CUMS‐induced depression‐like behavior in rats. Experimental techniques such as serum enzyme‐linked immunosorbent assay (ELISA), immunofluorescence, Western blot, and co‐immunoprecipitation, as well as in vitro experiments, were used to investigate the mechanisms by which Que exerts its antidepressant effects. Results: Behavioral and ELISA test results showed that Que could produce a reduction in the excitability of the hypothalamic–pituitary–adrenal (HPA) axis in CUMS rats and lead to significant improvements in their depressive behavior. Western blot, immunofluorescence, and co‐immunoprecipitation experiments showed that Que produced a decrease in NMDAR1 and α2δ‐1 expression levels and interfered with α2δ‐1 and NMDAR1 binding. In addition, the neural regulation mechanism of Que on antidepressant effect in PC12 cells knocked out α2δ‐1 gene was further verified. Cellular experiments demonstrated that Que led to a reversal of up‐regulation of NMDAR1 and α2δ‐1 expression levels in corticosterone‐injured PC12 cells, while Que had no effects on NMDAR1 expression in PC12 cells with the α2δ‐1 gene knockout. Conclusions: Que has a good antidepressant effect and can significantly improve the depression‐like behavior caused by CUMS. It exerts antidepressant effects by inhibiting the expression level of α2δ‐1, interfering with the interaction between α2δ‐1 and NMDAR, and then reducing the excitability of the HPA axis. [ABSTRACT FROM AUTHOR]

The electrocatalytic CO2 reduction (ECR) to produce valuable fuel is a promising process for addressing atmospheric CO2 emissions and energy shortages. In this study, Cl‐anion doped cadmium sulfide structures were directly fabricated on a nickel foam surface (Cl/CdS‐NF) using an in situ hydrothermal method. The Cl‐anion doping could significantly improve ECR activity for CO production in ionic liquid and acetonitrile mixed solution, compared to pristine CdS. The highest Faradaic efficiency of CO is 98.1 % on a Cl/CdS‐NF‐2 cathode with an excellent current density of 137.0 mA cm−2 at −2.25 V versus ferrocene/ferrocenium (Fc/Fc+, all potentials are versus Fc/Fc+ in this study). In particular, CO Faradaic efficiencies remained above 80 % in a wide potential range of −2.05 V to −2.45 V and a maximum partial current density (192.6 mA cm−2) was achieved at −2.35 V. The Cl/CdS‐NF‐2, with appropriate Cl anions, displayed abundant active sites and a suitable electronic structure, resulting in outstanding ECR activity. Density functional theory calculations further demonstrated that Cl/CdS is beneficial for increasing the adsorption capacities of *COOH and *H, which can enhance the activity of the ECR toward CO and suppress the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Background: Acromegaly is caused by the long‐term excessive secretion of growth hormone (GH) and insulin‐like growth factor‐1 (IGF‐1). It can cause excessive hyperplasia of bone, cartilage, and soft tissue. Case Presentation: A 50‐year‐old woman had a history of joint pain and swelling for more than 1 year. She visited a local primary care clinic, but her illness was not diagnosed by a primary care physician. After relevant examination in our hospital, we excluded inflammatory arthritis such as rheumatoid arthritis, immune disease‐related arthritis, and infectious arthritis, and considered osteoarthritis or endocrine–metabolic arthritis. When we examined her again, we found that her fingers and toes were enlarged. She was diagnosed with acromegaly after IGF‐1 test, and pituitary magnetic resonance imaging. Her joint symptoms were significantly relieved and her prognosis was good after surgery in another hospital. Conclusions: Acromegaly is a complex and rare disease, which is difficult to diagnose. When a patient presents with arthralgia, it is easily misdiagnosed as a rheumatic disease, and the diagnosis and treatment are delayed. [ABSTRACT FROM AUTHOR]

Mechanical force‐induced N2 fixation is an emerging strategy for single‐step ammonia synthesis under room temperature and atmospheric pressure. Here, we demonstrate a simple and rapid approach to synthesize NH3 in the N2+H2+H2O system and illustrate the reaction mechanism by theoretical calculations. The NH3 generation rate can reach 2.847 mg L−1 h−1 with an NH4+ selectivity of 99.45 wt.%. The presence of H2 can inhibit oxidation reactions to form NO3− by‐products and promote proton generation from H2O dissociation. The calculated formation energy of H‐adatom and OH‐adatom from H2O cleavage is −2.86 eV in N2+H2+H2O system, much lower than that in N2+H2O system, verifying much easier dissociation of H2O molecules and significantly facilitated proton generation to enlarge the NH4+ yield. This work provides a simple approach to improve mechanochemical N2 fixation performance and highlights a proton generation enhancement mechanism. [ABSTRACT FROM AUTHOR]