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Electroreduction of carbon dioxide (CO 2 ) over copper-based catalysts provides an attractive approach for sustainable fuel production. While efforts are focused on developing catalytic materials, it is also critical to understand and control the microenvironment around catalytic sites, which can mediate the transport of reaction species and influence reaction pathways. Here, we show that a hydrophobic microenvironment can significantly enhance CO 2 gas-diffusion electrolysis. For proof-of-concept, we use commercial copper nanoparticles and disperse hydrophobic polytetrafluoroethylene (PTFE) nanoparticles inside the catalyst layer. Consequently, the PTFE-added electrode achieves a greatly improved activity and Faradaic efficiency for CO 2 reduction, with a partial current density >250 mA cm −2 and a single-pass conversion of 14% at moderate potentials, which are around twice that of a regular electrode without added PTFE. The improvement is attributed to a balanced gas/liquid microenvironment that reduces the diffusion layer thickness, accelerates CO 2 mass transport, and increases CO 2 local concentration for the electrolysis. The local environment for carbon dioxide electrochemical reduction is a key element to improve the efficiency of catalytic sites. Here, the authors demonstrate substantial gain of the catalyst electrochemical activity through the adoption of a hydrophobic catalyst microenvironment.

ObjectiveDietary fibre has beneficial effects on energy metabolism, and the majority of studies have focused on short-chain fatty acids produced by gut microbiota. Ginseng has been reported to aid in body weight management, however, its mechanism of action is not yet clear. In this study, we focused on the potential modulating effect of ginseng on gut microbiota, aiming to identify specific strains and their metabolites, especially long-chain fatty acids (LCFA), which mediate the anti-obesity effects of ginseng.DesignDb/db mice were gavaged with ginseng extract (GE) and the effects of GE on gut microbiota were evaluated using 16S rDNA-based high throughput sequencing. To confirm the candidate fatty acids, untargeted metabolomics analyses of the serum and medium samples were performed.ResultsWe demonstrated that GE can induce Enterococcus faecalis, which can produce an unsaturated LCFA, myristoleic acid (MA). Our results indicate that E. faecalis and its metabolite MA can reduce adiposity by brown adipose tissue (BAT) activation and beige fat formation. In addition, the gene of E. faecalis encoding Acyl-CoA thioesterases (ACOTs) exhibited the biosynthetic potential to synthesise MA, as knockdown (KD) of the ACOT gene by CRISPR-dCas9 significantly reduced MA production. Furthermore, exogenous treatment with KD E. faecalis could not reproduce the beneficial effects of wild type E. faecalis, which work by augmenting the circulating MA levels.ConclusionsOur results demonstrated that the gut microbiota-LCFA-BAT axis plays an important role in host metabolism, which may provide a strategic advantage for the next generation of anti-obesity drug development.

Electrochemical reduction of N 2 to NH 3 provides an alternative to the Haber−Bosch process for sustainable, distributed production of NH 3 when powered by renewable electricity. However, the development of such process has been impeded by the lack of efficient electrocatalysts for N 2 reduction. Here we report efficient electroreduction of N 2 to NH 3 on palladium nanoparticles in phosphate buffer solution under ambient conditions, which exhibits high activity and selectivity with an NH 3 yield rate of ~4.5 μg mg −1 Pd h −1 and a Faradaic efficiency of 8.2% at 0.1 V vs. the reversible hydrogen electrode (corresponding to a low overpotential of 56 mV), outperforming other catalysts including gold and platinum. Density functional theory calculations suggest that the unique activity of palladium originates from its balanced hydrogen evolution activity and the Grotthuss-like hydride transfer mechanism on α-palladium hydride that lowers the free energy barrier of N 2 hydrogenation to *N 2 H, the rate-limiting step for NH 3 electrosynthesis. The Haber-Bosch process, producing NH 3 from N 2 , is a crucial yet energetically demanding reaction, inspiring interest in the exploration of ambient-condition alternatives. Here, authors develop a palladium electrocatalyst that shows a high selectivity and activity for N 2 reduction to NH 3 .

Imines conventionally act as electrophiles towards carbon nucleophiles in the synthesis of amines, but the range of amines could be much extended if the carbon atom of the imine could be rendered electron-rich to allow it to act as a nucleophile toward a carbon electrophile; such a reaction can be promoted by new phase-transfer catalysts, leading to highly efficient asymmetric reactions of imines with enals. Chital amine synthesis made simpler Imines, carbon–nitrogen double bonds, act as electrophiles towards carbon nucleophiles in the synthesis of amines, but the range of synthesizable amines could be greatly extended if the carbon atom of the imine could be rendered electron-rich to allow it to act as a nucleophile towards a carbon electrophile. Li Deng and colleagues have developed a procedure that achieves just that. They report the discovery and development of new chiral phase transfer catalysts that promote highly efficient asymmetric reactions of imines and enals. The reaction provides a conceptually new and practical approach towards the synthesis of chiral amino compounds. The carbon–nitrogen double bonds in imines are fundamentally important functional groups in organic chemistry. This is largely due to the fact that imines act as electrophiles towards carbon nucleophiles in reactions that form carbon–carbon bonds, thereby serving as one of the most widely used precursors for the formation of amines in both synthetic and biosynthetic settings 1 , 2 , 3 , 4 , 5 . If the carbon atom of the imine could be rendered electron-rich, the imine could react as a nucleophile instead of as an electrophile. Such a reversal in the electronic characteristics of the imine functionality would facilitate the development of new chemical transformations that convert imines into amines via carbon–carbon bond-forming reactions with carbon electrophiles, thereby creating new opportunities for the efficient synthesis of amines. The development of asymmetric umpolung reactions of imines (in which the imines act as nucleophiles) remains uncharted territory, in spite of the far-reaching impact such reactions would have in organic synthesis. Here we report the discovery and development of new chiral phase-transfer catalysts that promote the highly efficient asymmetric umpolung reactions of imines with the carbon electrophile enals. These catalysts mediate the deprotonation of imines and direct the 2-azaallyl anions thus formed to react with enals in a highly chemoselective, regioselective, diastereoselective and enantioselective fashion. The reaction tolerates a broad range of imines and enals, and can be carried out in high yield with as little as 0.01 mole per cent catalyst with a moisture- and air-tolerant operational protocol. These umpolung reactions provide a conceptually new and practical approach to chiral amino compounds.

Sleep disorder (SD) has a high incidence and seriously affects quality of life, mental health and even the manifestation of physical diseases. The combination of Pinellia ternata (Chinese name: banxia) and Prunella vulgaris  (Chinese name: xiakucao), known as the Banxia–Xiakucao Chinese herb pair (BXHP), is a proven Chinese herbal medicine that has been used to treat SD for thousands of years due to its significant clinical effects. However, its active pharmacological components and sedative–hypnotic mechanisms have not been fully elucidated. Thus, the present study used a systematic pharmacological approach to develop pharmacokinetic screens and target predictions via construction of a protein–protein interaction network and annotation database for SD-related and putative BXHP-related targets. Visualization, screening and integrated discovery enrichment analyses were conducted. The BXHP chemical database contains 166 compounds between the two herbal ingredients, and of these, 22 potential active molecules were screened by pharmacokinetic evaluation. The targets of 114 of the active molecules were predicted, and 34 were selected for further analysis. Finally, gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses suggested that BXHP can reduce inflammatory responses. and mediate immune-related and central nervous system neurotransmitters via regulation of multiple targets and pathways. The use of a systematic pharmacology-based approach in the present study further elucidated the mechanisms of action underlying BXHP for the treatment of SD from a holistic perspective and sheds light on the systemic mechanisms of action of Chinese herbal medicines in general.

Background Oocyte quality is critical for the mammalian reproduction due to its necessity on fertilization and early development. During aging, the declined oocytes showing with organelle dysfunction and oxidative stress lead to infertility. AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase which is important for energy homeostasis for metabolism. Little is known about the potential relationship between AMPK with oocyte aging. Results In present study we reported that AMPK was related with low quality of oocytes under post ovulatory aging and the potential mechanism. We showed the altered AMPK level during aging and inhibition of AMPK activity induced mouse oocyte maturation defect. Further analysis indicated that similar with its upstream regulator PKD1, AMPK could reduce ROS level to avoid oxidative stress in oocytes, and this might be due to its regulation on mitochondria function, since loss of AMPK activity induced abnormal distribution, reduced ATP production and mtDNA copy number of mitochondria. Besides, we also found that the ER and Golgi apparatus distribution was aberrant after AMPK inhibition, and enhanced lysosome function was also observed. Conclusions Taken together, these data indicated that AMPK is important for the organelle function to reduce oxidative stress during oocyte meiotic maturation.

KIFC3 is a member of Kinesin-14 family motor proteins, which play a variety of roles such as centrosome cohesion, cytokinesis, vesicles transportation and cell proliferation in mitosis. Here, we investigated the functional roles of KIFC3 in meiosis. Our findings demonstrated that KIFC3 exhibited expression and localization at centromeres during metaphase I, followed by translocation to the midbody at telophase I throughout mouse oocyte meiosis. Disruption of KIFC3 activity resulted in defective polar body extrusion. We observed aberrant meiotic spindles and misaligned chromosomes, accompanied by the loss of kinetochore-microtubule attachment, which might be due to the failed recruitment of BubR1/Bub3. Coimmunoprecipitation data revealed that KIFC3 plays a crucial role in maintaining the acetylated tubulin level mediated by Sirt2, thereby influencing microtubule stability. Additionally, our findings demonstrated an interaction between KIFC3 and PRC1 in regulating midbody formation during telophase I, which is involved in cytokinesis regulation. Collectively, these results underscore the essential contribution of KIFC3 to spindle assembly and cytokinesis during mouse oocyte meiosis.

Non-small cell lung cancer (NSCLC) shows high drug resistance and leads to low survival due to the high level of mutated Tumor Protein p53 ( TP53 ). Cisplatin is a first-line treatment option for NSCLC, and the p53 mutation is a major factor in chemoresistance. We demonstrate that cisplatin chemotherapy increases the risk of TP53 mutations, further contributing to cisplatin resistance. Encouragingly, we find that the combination of cisplatin and fluvastatin can alleviate this problem. Therefore, we synthesize Fluplatin, a prodrug consisting of cisplatin and fluvastatin. Then, Fluplatin self-assembles and is further encapsulated with poly-(ethylene glycol)–phosphoethanolamine (PEG–PE), we obtain Fluplatin@PEG–PE nanoparticles (FP NPs). FP NPs can degrade mutant p53 (mutp53) and efficiently trigger endoplasmic reticulum stress (ERS). In this study, we show that FP NPs relieve the inhibition of cisplatin chemotherapy caused by mutp53, exhibiting highly effective tumor suppression and improving the poor NSCLC prognosis. In non-small cell lung cancer (NSCLC), inactivating p53 mutations can drive resistance to cisplatin. Here, the authors develop fluplatin nanoparticles comprising a prodrug of cisplatin and fluvastin (mutant p53 inhibitor) which selectively degrades mutant p53, prevent tumor recurrences in preclinical models of p53 mutant NSCLC.

Ferrocene and its derivatives, especially ferrocene‐based coordination polymers (Fc‐CPs), offer the benefits of high thermal stability, two stable redox states, fast electron transfer, and excellent charge/discharge efficiency, thus holding great promise for electrochemical applications. Herein, we describe the synthesis and electrochemical applications of Fc‐CPs and reveal how the incorporation of ferrocene units into coordination polymers containing other metals results in unprecedented properties. Moreover, we discuss the usage of Fc‐CPs in supercapacitors, batteries, and sensors as well as further applications of these polymers, for example in electrocatalysts, water purification systems, adsorption/storage systems. Iron strength: The incorporation of ferrocene as an organometallic building block into coordination polymers containing other metals to impart certain properties can afford attractive structures denoted as ferrocene‐based coordination polymers. This Review focuses on the synthesis and electrochemical applications (e. g., supercapacitors, batteries, electrosensors, and electrocatalysts) of these coordination polymers.