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Introduction Material and Methods Results Conclusions Previous studies have established a link between gut microbiota and polycystic ovary syndrome (PCOS), but little is known about their precise causal relationship. Therefore, this study aims to explore whether there are precise causal relationships between gut microbiota and PCOS.We performed a bidirectional two‐sample Mendelian randomization (MR) analysis. Datasets were from the largest published meta‐analysis on gut microbiota composition and the FinnGen cohort of the IEU Open Genome‐Wide Association Study Project database. Inverse variance weighted (IVW), MR‐Egger, constrained maximum likelihood‐based Mendelian randomization, weighted median, weighted mode, and simple mode were used. Cochran's Q and MR‐Egger intercept tests were employed to measure the heterogeneity.A total of 211 gut microbiota taxa were identified in MR analysis. Nine taxa of bacteria, including Alphaproteobacteria (0.55, 0.30–0.99, p = 0.04), Bacilli (1.76, 1.07–2.91, p = 0.03), Bilophila (0.42, 0.23–0.77, p < 0.01), Blautia (0.16, 0.03–0.79, p = 0.02), Burkholderiales (2.37, 1.22–4.62, p = 0.01), Candidatus Soleaferrea (0.65, 0.43–0.98, p = 0.04), Cyanobacteria (0.51, 0.31–0.83, p = 0.01), Holdemania (0.53, 0.35–0.81, p < 0.01), and Lachnospiraceae (1.86, 1.04–3.35, p = 0.03), were found to be associated with PCOS in the above MR methods included at least IVW method. Cochran's Q statistics and MR‐Egger intercept test suggested no significant heterogeneity. In addition, 69 taxa were shown significant for at least the IVW method in reverse MR analysis, of these, 25 had a positive correlation, and 37 had a negative correlation. Additionally, Alphaproteobacteria and Lachnospiraceae (0.95, 0.91–0.98, p < 0.01; 0.97, 0.94–0.99, p = 0.02, respectively) were shown a bidirected causally association with PCOS.Our study provides evidence of the bidirectional causal association between gut microbiota and PCOS from a genetic perspective. [ABSTRACT FROM AUTHOR]

End‐ischemic normothermic mechanical perfusion (NMP) could provide a curative treatment to reduce cholestatic liver injury from donation after circulatory death (DCD) in donors. However, the underlying mechanism remains elusive. Our previous study demonstrated that air‐ventilated NMP could improve functional recovery of DCD in a preclinical NMP rat model. Here, metabolomics analysis revealed that air‐ventilated NMP alleviated DCD‐ and cold preservation‐induced cholestatic liver injury, as shown by the elevated release of alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and γ‐glutamyl transferase (GGT) in the perfusate (p <.05) and the reduction in the levels of bile acid metabolites, including ω‐muricholic acid, glycohyodeoxycholic acid, glycocholic acid, and glycochenodeoxycholate (GCDC) in the perfused livers (p <.05). In addition, the expression of the key bile acid metabolism enzyme UDP‐glucuronosyltransferase 1A1 (UGT1A1), which is predominantly expressed in hepatocytes, was substantially elevated in the DCD rat liver, followed by air‐ventilated NMP (p <.05), and in vitro, this increase was induced by decreased GCDC and hypoxia‐reoxygenation in the hepatic cells HepG2 and L02 (p <.05). Knockdown of UGT1A1 in hepatic cells by siRNA aggravated hepatic injury caused by GCDC and hypoxia‐reoxygenation, as indicated by the ALT and AST levels in the supernatant. Mechanistically, UGT1A1 is transcriptionally regulated by peroxisome proliferator‐activator receptor‐γ (PPAR‐γ) under hypoxia–physoxia. Taken together, our data revealed that air‐ventilated NMP could alleviate DCD‐ and cold preservation‐induced cholestatic liver injury through PPAR‐γ/UGT1A1 axis. Based on the results from this study, air‐ventilated NMP confers a promising approach for predicting and alleviating cholestatic liver injury through PPAR‐γ/UGT1A1 axis. [ABSTRACT FROM AUTHOR]

In this paper, with the assumption of only channel statistics information available at the receivers, a novel concept of multiplicative uniquely decomposable constellations is proposed for multi‐user single‐input multiple‐output (MU‐SIMO) FSO systems in weak atmospheric turbulence, which is modeled by spatially dependent lognormal fading channels. The design enables the fast decoding at the users' sides and meanwhile allows flexibility in assigning each user's ordering to meet different priority needs. Simulation results show that our proposed design has a significant performance improvement over the TDMA scheme at the same rates. [ABSTRACT FROM AUTHOR]

The recently developed clustered regularly interspaced short palindromic repeats (CRISPR)‐based techniques have made it possible to reprogram target gene expression without cloning complementary DNA or disturbing genomic sequence in mammalian cells and several multicellular organisms. We previously showed that CRISPR‐associated protein 9 (Cas9) and CRISPR from Prevotella and Francisella 1 (Cpf1) could induce target mutations, deletions, inversions, and duplications both singly and multiplex in silkworm, Bombyx mori. However, it remains unknown whether the CRISPR activation (CRISPRa) system can be used in B. mori. In this study, we investigated the CRISPRa system, in which a nuclease dead Streptococcus pyogenes Cas9 (SpCas9) is fused to two transcription activation domains, including VP64 (a tetramer of the herpes simplex VP16 transcriptional activator domain), and VPR (a tripartite activator, composed of VP64, p65, and Rta). The results showed that both dCas9‐VP64 and dCas9‐VPR systems could be used in B. mori cells, of which the latter showed significantly higher activity. The dCas9‐VPR system showed considerable activity on all five tested target genes, and further analysis revealed that the up‐regulation of genes was negatively correlated to their basal expression level. We also observed that this system could be used to upregulate a range of target genes. Taken together, our findings demonstrate that CRISPRa can be a powerful tool to study gene functions in B. mori and perhaps other non‐drosophila insects. [ABSTRACT FROM AUTHOR]

Suspended strip-line (SSL) filter is of wide application values for its low insertion loss, high quality factor value, easy integration and compact size. In this letter, we proposed the design of a dual-band SSL band-pass filter based on electric metamaterials, which is realized by introducing a rejection band inside the wide pass-band of a conventional SSL filter. The electric metamaterial can produce negative permittivity and thus hinders the transmission of EM waves along the strip-line. To verify the design method, a prototype, together with a conventional SSL filter for comparison, was designed, fabricated and measured. Both the simulation and experiment results verify the dual-band band-pass filtering property. [ABSTRACT FROM AUTHOR]

The brown planthopper ( Nilaparvata lugens, BPH), white-backed planthopper ( Sogatella furcifera, WBPH) and small brown planthopper ( Laodelphax striatellus, SBPH) are important rice pests in Asia. These three species differ in thermal tolerance and exhibit quite different migration and overwintering strategies. To understand the underlying mechanisms, we sequenced and compared the transcriptome of the three species under different temperature treatments. We found that metabolism-, exoskeleton- and chemosensory-related genes were modulated. In high temperature (37 °C), heat shock protein ( HSP) genes were the most co-regulated; other genes related with fatty acid metabolism, amino acid metabolism and transportation were also differentially expressed. In low temperature (5 °C), the differences in gene expression of the genes for fatty acid synthesis, transport proteins and cytochrome P450 might explain why SBPH can overwinter in high latitudes, while BPH and WBPH cannot. In addition, other genes related with moulting, and membrane lipid composition might also play roles in resistance to low and high temperatures. Our study illustrates the common responses and different tolerance mechanisms of three rice planthoppers in coping with temperature change, and provides a potential strategy for pest management. [ABSTRACT FROM AUTHOR]

A variety of oxazole derivatives including alkaloid halfordinol (VIII) is readily prepared by a oxidative cyclization of bromoketones with amines. [ABSTRACT FROM AUTHOR]