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71.
Luhua Xiao Xiaoying Lu Huilin Yang Cuiqing Lin Le Li Chen Ni Yuan Fang Suifen Mo Ruoting Zhan Ping Yan 《Molecules (Basel, Switzerland)》2022,27(11)
In this study, the antioxidant and hypolipidemic effects of Mesona Chinensis Benth (MCB) extracts were evaluated. Seven fractions (F0, F10, F20, F30, F40, F50 and MTF) were obtained from the MCB ethanol extracts. Compared to the commercial antioxidants (vitamin C), MTF and F30 exhibited higher antioxidant activities in the antiradical activity test and the FRAP assay. The half-inhibition concentration (IC50) for MTF and F30 were 5.323 µg/mL and 5.278 µg/mL, respectively. MTF at 200 µg/mL significantly decreased the accumulation of TG in oleic acid (OA)-induced HepG2 cells and reversed the inhibitory effect of Compound C on AMPK (MTF and F30 significantly increased the glucose utilization of insulin-induced HepG2 cells). In addition, the components of MTF were identified by HPLC-MS, which were caffeic acid, quercetin 3-O-galactoside, isoquercetin, astragalin, rosmarinic acid, aromadendrin-3-O-rutinoside, rosmarinic acid-3-O-glucoside and kaempferol-7-O-glucoside. Through statistical correlations by Simca P software, it was found that the main antioxidant and hypolipidemic components of MCB might be caffeic acid, kaempferol-7-O-glucoside, rosmarinic acid-3-O-glucoside and aromadendrin-3-O-rutinoside, which may play important roles in the AMPK pathway. MTF and F30 in MCB could be potential health products for the treatment of hyperlipidemia. 相似文献
72.
Inclusive γ(1S,2S,3S) photoproduction at the future Circular-Electron-Positron-Collider(CEPC)is studied,using the non-relativistic quantum chromodynamics(NRQCD)factorization formalism.Including the contributions from both direct and resolved photons,we present different distributions for the γ(1S,2S,3S) production.Our results suggest that there will be considerable events,implying that well measurements of the T photoproduction can be performed to further study heavy quarkonium physics at electron-positron colliders,in addition to hadron colliders.This supplemental study is very important for clarifying the current situation regarding the heavy quarkonium production mechanism. 相似文献
73.
Shengnan Xie Li Li Baihe Zhan Xue Shen Xuming Deng Wenxi Tan Tianqi Fang 《Molecules (Basel, Switzerland)》2022,27(9)
The emergence of the plasmid-mediated colistin resistance gene mcr-1 has resulted in the loss of available treatments for certain severe infections. Here we identified a potential inhibitor of MCR-1 for the treatment of infections caused by MCR-1-positive drug-resistant bacteria, especially MCR-1-positive carbapenem-resistant Enterobacteriaceae (CRE). A checkerboard minimum inhibitory concentration (MIC) test, a killing curve test, a growth curve test, bacterial live/dead assays, scanning electron microscope (SEM) analysis, cytotoxicity tests, molecular dynamics simulation analysis, and animal studies were used to confirm the in vivo/in vitro synergistic effects of pogostone and colistin. The results showed that pogostone could restore the bactericidal activity of colistin against all tested MCR-1-positive bacterial strains or MCR-1 mutant–positive bacterial strains (FIC < 0.5). Pogostone does not inhibit the expression of MCR-1. Rather, it inhibits the binding of MCR-1 to substrates by binding to amino acids in the active region of MCR-1, thus inhibiting the biological activity of MCR-1 and its mutants (such as MCR-3). An in vivo mouse systemic infection model, pogostone in combination with colistin resulted in 80.0% (the survival rates after monotherapy with colistin or pogostone alone were 33.3% and 40.0%) survival at 72 h after infection of MCR-1-positve Escherichia coli (E. coli) ZJ487 (blaNDM-1-carrying), and pogostone in combination with colistin led to one or more order of magnitude decreases in the bacterial burdens in the liver, spleen and kidney compared with pogostone or colistin alone. Our results confirm that pogostone is a potential inhibitor of MCR-1 for use in combination with polymyxin for the treatment of severe infections caused by MCR-1-positive Enterobacteriaceae. 相似文献
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石墨烯及其衍生物作为新型碳纳米结构,由于其优异的光限幅性能而受到广泛关注,但现有的工作多侧重于其在液相体系中光限幅效应及其起因研究.本文以壳聚糖为成膜基质,将氧化石墨烯(GO)与壳聚糖(CS)在液相中均匀共混后成膜,对比研究GO溶液和GO-CS复合膜的光限幅效应及其起因.结果表明在线性透过率相同的情况下,GO在固相基质中表现出比液相基质更强的光限幅效应和更弱的非线性散射.这说明不同于碳纳米管简单的非线性散射,在GO中可能存在多种非线性光学效应. 相似文献
76.
基于激光加载的材料状态方程的实验研究对靶面光强分布的均匀性及稳定性提出了极高的要求,靶面光强的上述两大特性在很大程度上决定了实验结果的精度和可重复性.本文针对传统窄带高相干激光装置在激光加载材料状态方程实验中表现出的靶面光强均匀性和光强分布稳定性两方面可能存在的问题,提出了基于宽带低相干激光,利用消衍射阵列透镜联合诱导非相干技术的束匀滑方案,并重点分析了波前相位畸变对靶面不均匀性及稳定性的影响.模拟结果表明,该方法明显降低了靶面不均匀性,提高了对波前相位畸变的包容度,获得了均匀、稳定的光强分布.统计分析显示,焦斑强度分布极差和不均匀性与波前相位畸变均方根梯度相关性较强.因此,可以根据统计结果以及实验对焦斑强度分布的要求,给出波前相位畸变的容差范围,对状态方程实验中激光驱动器参数的设计与优化具有指导意义. 相似文献
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Wine has become a commodity of significant commercial value, and the demand for high quality wine by consumers has been increasing. Suitable analytical techniques are needed for its quality control. Ultraviolet, Visible, Near-infrared and infrared spectroscopy is by far one of the most important techniques for determining the wine quality, including its components and characterization. This review will overview the available most recent applications of spectroscopic techniques in the past decade for wine quality prediction and discrimination both quantitatively and qualitatively. The fundamental principles of these techniques will be introduced briefly, and some innovative setups/instrumentations will also be illustrated. At last the limitations and prospects of spectroscopic techniques for wine industry will be discussed. 相似文献
80.
Tailorable PC71BM Isomers: Using the Most Prevalent Electron Acceptor to Obtain High‐Performance Polymer Solar Cells
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Xin‐Xing Zhan Xin Zhang Si‐Min Dai Shu‐Hui Li Xu‐Zhai Lu Dr. Lin‐Long Deng Prof. Su‐Yuan Xie Prof. Rong‐Bin Huang Prof. Lan‐Sun Zheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18709-18713
Despite being widely used as electron acceptor in polymer solar cells, commercially available PC71BM (phenyl‐C71‐butyric acid methyl ester) usually has a “random” composition of mixed regioisomers or stereoisomers. Here PC71BM has been isolated into three typical isomers, α‐, β1‐ and β2‐PC71BM, to establish the isomer‐dependent photovoltaic performance on changing the ternary composition of α‐, β1‐ and β2‐PC71BM. Mixing the isomers in a ratio of α/β1/β2=8:1:1 resulted in the best power conversion efficiency (PCE) of 7.67 % for the polymer solar cells with PTB7:PC71BM as photoactive layer (PTB7=poly[[4,8‐bis[(2‐ethylhexyl)oxy]benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl][3‐fluoro‐2‐[(2‐ethylhexyl)carbonyl]thieno[3,4‐b]thiophenediyl]]). The three typical PC71BM isomers, even though sharing similar LUMO energy levels and light absorption, render starkly different photovoltaic performances with average‐performing PCE of 1.28–7.44 % due to diverse self‐aggregation of individual or mixed PC71BM isomers in the otherwise same polymer solar cells. 相似文献