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Gestational diabetes mellitus (GDM) is known as different degree glucose intolerance that is initially identified during pregnancy. MicroRNAs (miRs) may be a potential candidate for treatment of GDM. Herein, we suggested that miR‐351 could be an inhibitor in the progression of GDM via the phosphoinositide 3‐kinase/protein kinase B (PI3K/AKT) pathway. Microarray analysis was used to identify differentially expressed genes and predict miRs regulating flotillin 2 (FLOT2). Target relationship between miR‐351 and FLOT2 was verified. Gestational diabetes mellitus mice were treated with a series of mimic, inhibitor and small interfering RNA to explore the effect of miR‐351 on insulin resistance (IR), cell apoptosis in pancreatic tissues and liver gluconeogenesis through evaluating GDM‐related biochemical indexes, as well as expression of miR‐351, FLOT2, PI3K/AKT pathway‐, IR‐ and liver gluconeogenesis‐related genes. MiR‐351 and FLOT2 were reported to be involved in GDM. FLOT2 was the target gene of miR‐351. Gestational diabetes mellitus mice exhibited IR and liver gluconeogenesis, up‐regulated FLOT2, activated PI3K/AKT pathway and down‐regulated miR‐351 in liver tissues. Additionally, miR‐351 overexpression and FLOT2 silencing decreased the levels of FLOT2, phosphoenolpyruvate carboxykinase, glucose‐6‐phosphatase, fasting blood glucose, fasting insulin, total cholesterol, triglyceride, glyeosylated haemoglobin and homeostasis model of assessment for IR index (HOMA‐IR), extent of PI3K and AKT phosphorylation, yet increased the levels of HOMA for islet β‐cell function, HOMA for insulin sensitivity index and glucose transporter 2 expression, indicating reduced cell apoptosis in pancreatic tissues and alleviated IR and liver gluconeogenesis. Our results reveal that up‐regulation of miR‐351 protects against IR and liver gluconeogenesis by repressing the PI3K/AKT pathway through regulating FLOT2 in GDM mice, which identifies miR‐351 as a potential therapeutic target for the clinical management of GDM.  相似文献   
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Long noncoding RNAs (lncRNAs) are involved in the pathology of various tumours, including non‐small cell lung cancer (NSCLC). However, the underlying molecular mechanisms of their specific association with NSCLC have not been fully elucidated. Here, we report that a cytoplasmic lncRNA, DUXAP9‐206 is overexpressed in NSCLC cells and closely related to NSCLC clinical features and poor patient survival. We reveal that DUXAP9‐206 induced NSCLC cell proliferation and metastasis by directly interacting with Cbl‐b, an E3 ubiquitin ligase, and reducing the degradation of epidermal growth factor receptor (EGFR) and thereby augmenting EGFR signaling in NSCLC. Notably, correlations between DUXAP9‐206 and activated EGFR signaling were also validated in NSCLC patient specimens. Collectively, our findings reveal the novel molecular mechanisms of DUXAP9‐206 in mediating the progression of NSCLC and DUXAP9‐206 may serve as a potential target for NSCLC therapy.  相似文献   
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Seven new polyhydroxypregnane glycosides, named cynotophyllosides P–V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid . Their structures were elucidated by a variety of spectroscopic techniques, as well as acid‐catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A‐ and LPS‐induced proliferation of mice splenocytes. Immunoenhancing (for 1 , 9 ) and immunosuppressive (for 2 ) activities were observed. Furthermore, cynotophylloside R ( 3 ) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 μg/ml.  相似文献   
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Anodically electrodeposited amorphous molybdenum sulfide (AE‐MoSx) has attracted significant attention as a non‐noble metal electrocatalyst for its high activity toward the hydrogen evolution reaction (HER). The [Mo3S13]2? polymer‐based structure confers a high density of exposed sulfur moieties, widely regarded as the HER active sites. However, their intrinsic complexity conceals full understanding of their exact role in HER catalysis, hampering their full potential for water splitting applications. In this report, a unifying approach is adopted accounting for modifications in the inherent electrochemistry (EC), HER mechanism, and surface species to maximize the AE‐MoSx electroactivity over a broad pH region (0–10). Dramatic enhancements in HER performance by selective electrochemical cycling within reductive (overpotential shift, ηHER ≈ ?350 mV) and electro‐oxidative windows (ηHER ≈ ?290 mV) are accompanied by highly stable performance in mildly acidic electrolytes. Joint analysis of X‐ray photoelectron spectroscopy, Raman, and EC experiments corroborate the key role of bridging and terminal S ligands as active site generators at low pH, and reveal molybdenum oxysulfides (Mo5+OxSy) to be the most active HER moiety in AE‐MoSx in mildly acidic‐to‐neutral environments. These findings will be extremely beneficial for future tailoring of MoSx materials and their implementation in commercial electrolyzer technologies.  相似文献   
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Yang  Shu  Zhao  Kang  Xu  Zhengtian 《Plasmonics (Norwell, Mass.)》2019,14(6):1377-1384

Two kinds of graphene-coated fiber systems are proposed and studied for optical trapping. Their plasmonic modes in uniform environment and close to the substrate are studied in the finite element method. The optical forces exerted on dielectric nanoparticle by these systems are calculated by standalone waveguide approximation. It is found that for the dielectric particle with diameter of 1 nm, the maximal optical forces generated by certain modes are more than 107 fN/W whereas their force ranges are only one to several nanometers. These results may have important applications in strong and high-precision optical tweezers.

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The ability of a blood clot to modulate blood flow is determined by the clot’s resistance, which depends on its structural features. For a flow with arterial shear, we investigated the characteristic patterns relating to clot shape, size, and composition on the one hand, and its viscous resistance, intraclot axial flow velocity, and shear distributions on the other. We used microfluidic technology to measure the kinetics of platelet, thrombin, and fibrin accumulation at a thrombogenic surface coated with collagen and tissue factor (TF), the key clot-formation trigger. We subsequently utilized the obtained data to perform additional calibration and validation of a detailed computational fluid dynamics model of spatial clot growth under flow. We then ran model simulations to gain insights into the resistance of clots formed under our experimental conditions. We found that increased thrombogenic surface length and TF surface density enhanced the bulk thrombin and fibrin generation in a nonadditive, synergistic way. The height of the platelet deposition domain—and, therefore, clot occlusivity—was rather robust to thrombogenic surface length and TF density variations, but consistently increased with time. Clot viscous resistance was non-uniform and tended to be higher in the fibrin-rich, inner “core” region of the clot. Interestingly, despite intraclot structure and viscous resistance variations, intraclot flow velocity variations were minor compared to the abrupt decrease in flow velocity around the platelet deposition region. Our results shed new light on the connection between the structure of clots under arterial shear and spatiotemporal variations in their resistance to flow.

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