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81.
Juan Chen Yixuan Chen Yangfan Zheng Jiawen Zhao Huilin Yu Jiajin Zhu 《Molecules (Basel, Switzerland)》2022,27(15)
This study evaluated the effect of grape seed-derived monomer, dimeric, and trimeric procyanidins on rat pheochromocytoma cell line (PC12) cells and in a zebrafish Parkinson’s disease (PD) model. PC12 cells were cultured with grape seed-derived procyanidins or deprenyl for 24 h and then exposed to 1.5 mm 1-methyl-4-phenylpyridinium (MPP+) for 24 h. Zebrafish larvae (AB strain) 3 days post-fertilization were incubated with deprenyl or grape seed-derived procyanidins in 400 µM 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 4 days. The results showed that the procyanidin dimers procyanidin B1 (B1), procyanidin B2 (B2), procyanidin B3 (B3), procyanidin B4 (B4), procyanidin B1-3-O-gallate (B1-G), procyanidin B2-3-O-gallate (B2-G), and the procyanidin trimer procyanidin C1 (C1) had a protective effect on PC12 cells, decreasing the damaged dopaminergic neurons and motor impairment in zebrafish. In PC12 cells and the zebrafish PD model, procyanidin (B1, B2, B3, B4, B1-G, B2-G, C1) treatment decreased the content of reactive oxygen species (ROS) and malondialdehyde (MDA), increased the activity of antioxidant enzymes glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD), and upregulated the expression of nuclear factor-erythroid 2-related factor (Nrf2), NAD(P)H: quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1). These results suggest that in PC12 cells and the zebrafish PD model, the neuroprotective effects of the procyanidins were positively correlated with their degree of polymerization. 相似文献
82.
Yue Liu Congmin Wang Rong Guo Juexiu Li Quan Zhao Weiqiang Wang Fei Qi Haifang Liu Yang Li Huifan Zheng 《Molecules (Basel, Switzerland)》2022,27(15)
Iron–manganese silicate (IMS) was synthesized by chemical coprecipitation and used as a catalyst for ozonating acrylic acid (AA) in semicontinuous flow mode. The Fe-O-Mn bond, Fe-Si, and Mn-Si binary oxide were formed in IMS on the basis of the results of XRD, FTIR, and XPS analysis. The removal efficiency of AA was highest in the IMS catalytic ozonation processes (98.9% in 15 min) compared with ozonation alone (62.7%), iron silicate (IS) catalytic ozonation (95.6%), and manganese silicate catalytic ozonation (94.8%). Meanwhile, the removal efficiencies of total organic carbon (TOC) were also improved in the IMS catalytic ozonation processes. The IMS showed high stability and ozone utilization. Additionally, H2O2 was formed in the process of IMS catalytic ozonation. Electron paramagnetic resonance (EPR) analysis and radical scavenger experiments confirmed that hydroxyl radicals (•OH) were the dominant oxidants. Cl−, HCO3−, PO43−, Ca2+, and Mg2+ in aqueous solution could adversely affect AA degradation. In the IMS catalytic ozonation of AA, the surface hydroxyl groups and Lewis acid sites played an important role. 相似文献
83.
Ruiyang Li Haiming Hua Yuejing Zeng Jin Yang Zhiqiang Chen Peng Zhang Jinbao Zhao 《Journal of Energy Chemistry》2022,(1):395-403
Poly(ethylene oxide)(PEO) is a classic matrix model for solid polymer electrolyte which can not only dissociate lithium-ions(Li+),but also can conduct Li+through segmental motion in long-range.However,the crystal aggregation state of PEO restricts the conduction of Li+ especially at room temperature.In this work,an amorphous polymer electrolyte with ethylene oxide(EO) and propylene oxide(PO) block structure(B-PEG@DMC) synthesized by the transesterification is firstly obtained,showing ... 相似文献
84.
Two bis-imidazolium salts LH2·Cl2 and LH2·(PF6)2 with acylated piperazine linker and two N-heterocyclic carbene (NHC) silver(Ⅰ) and palladium(Ⅱ) complexes[L2Ag2... 相似文献
85.
Li Xiong Jin Hu Zhao Yang Xianglin Li Hang Zhang Guanhua Zhang 《Molecules (Basel, Switzerland)》2022,27(12)
This study presents the construction and dielectric properties investigation of atomic-layer-deposition Al2O3/TiO2/HfO2 dielectric-film-based metal–insulator–metal (MIM) capacitors. The influence of the dielectric layer material and thickness on the performance of MIM capacitors are also systematically investigated. The morphology and surface roughness of dielectric films for different materials and thicknesses are analyzed via atomic force microscopy (AFM). Among them, the 25 nm Al2O3-based dielectric capacitor exhibits superior comprehensive electrical performance, including a high capacitance density of 7.89 fF·µm−2, desirable breakdown voltage and leakage current of about 12 V and 1.4 × 10−10 A·cm−2, and quadratic voltage coefficient of 303.6 ppm·V−2. Simultaneously, the fabricated capacitor indicates desirable stability in terms of frequency and bias voltage (at 1 MHz), with the corresponding slight capacitance density variation of about 0.52 fF·µm−2 and 0.25 fF·µm−2. Furthermore, the mechanism of the variation in capacitance density and leakage current might be attributed to the Poole–Frenkel emission and charge-trapping effect of the high-k materials. All these results indicate potential applications in integrated passive devices. 相似文献
86.
Objectives Green tea (Camellia sinensis) is a kind of unfermented tea that retains the natural substance in fresh leaves to a great extent. It is regarded as the second most popular drink in the world besides water. In this paper, the phytochemistry, pharmacology, and toxicology of green tea are reviewed systematically and comprehensively. Key findings Green tea has been demonstrated to be good for human health. Nowadays, multiple pharmacologically active components have been isolated and identified from green tea, including tea polyphenols, alkaloids, amino acids, polysaccharides, and volatile components. Recent studies have demonstrated that green tea shows versatile pharmacological activities, such as antioxidant, anticancer, hypoglycemic, antibacterial, antiviral, and neuroprotective. Studies on the toxic effects of green tea extract and its main ingredients have also raised concerns including hepatotoxicity and DNA damage. Summary Green tea can be used to assist the treatment of diabetes, Alzheimer’s disease, oral cancer, and dermatitis. Consequently, green tea has shown promising practical prospects in health care and disease prevention. 相似文献
87.
A convenient and regioselective sulfonylation/cyclization of 1,6-enynes with arylazo sulfones has been developed to access a series of sulfonylated γ-butyrolactams.The present reaction could be efficiently conducted under catalyst-and additive-free conditions,in which C-S and C-C bonds were selectively constructed in one-pot procedure. 相似文献
88.
As multilayer networks are widely applied in modern society, numerous studies have shown the impact of a multilayer network structure and the network nature on the proportion of cooperators in the network. In this paper, we use Barabási–Albert scale-free networks (BA) and Watts and Strogatz networks (WS) to build a multilayer network structure, and we propose a new strategy-updating rule called “cooperation-defection dominance”, which can be likened to dominant and recessive traits in biogenetics. With the newly constructed multilayer network structure and the strategy-updating rules, based on the simulation results, we find that in the BA-BA network, the cooperation dominance strategy can make the networks with different rs show a cooperative trend, while the defection dominance strategy only has an obvious effect on the network cooperation with a larger r. When the BA network is connected to the WS network, we find that the effect of strategy on the proportion of cooperators in the network decreases, and the main influencing factor is the structure of the network. In the three-layer network, the cooperation dominance strategy has a greater impact on the BA network, and the proportion of the cooperators is enhanced more than under the natural evolution strategy, but the promotion effect is still smaller than that of the two-layer BA network because of the WS network. Under the defection dominance strategy, the WS layer appears different from the first two strategies, and we conclude through simulation that when the payoff parameter is at the middle level, its cooperator proportion will be suppressed, and we deduce that the proportion of cooperators and defectors, as well as the payoff, play an important role. 相似文献
89.
Xuan Zhao Jiqing Fang Yu Jia Zi Wu Meihui Zhang Mingyu Xia Jinhua Dong 《Molecules (Basel, Switzerland)》2022,27(11)
A series of 1,7-diphenyl-1,4-heptadien-3-ones with various substituents (HO-, CH3O-, CH3-, Cl-) on the phenyl rings were synthesized and evaluated for anti-neuroinflammatory effects in LPS-stimulated BV2 microglia. The pharmacological results showed that the target compounds bearing methoxy groups greatly inhibited LPS-induced NO release, and that the active compounds CU-19 and CU-21 reduced the level of NO, TNF-α, IL-6 and PGE-2, downregulated the expression of COX-2 and iNOS in LPS-stimulated BV2 cells. A study of the mechanism of action revealed that CU-19 and CU-21 inhibited the nuclear translocation of NF-κB and phosphorylation of MAPKs (ERK, JNK, and p38). A preliminary pharmacokinetic study in rats revealed that the pharmacokinetic properties of CU-19 and CU-21 were dramatically ameliorated in comparison with the pharmacokinetic properties of curcumin. 相似文献
90.
Chang-Shu Cheng Qing-Hui Gu Jin-Ke Zhang Jun-Hong Tao Tian-Rui Zhao Jian-Xin Cao Gui-Guang Cheng Guo-Fang Lai Ya-Ping Liu 《Molecules (Basel, Switzerland)》2022,27(11)
The bud of Vaccinium dunalianum Wight has been traditionally consumed as health herbal tea by “Yi” people in Yunnan Province, China, which was locally named “Que Zui tea”. This paper studied the chemical constituents of five fractions from Vaccinium dunalianum, and their enzyme inhibitory effects of α-glucosidase and pancreatic lipase, antioxidant activity, and cytoprotective effects on H2O2-induced oxidative damage in HepG2 cells. The methanol extract of V. dunalianum was successively partitioned with petroleum ether (PF), chloroform (CF), ethyl acetate (EF), n-butanol (BF), and aqueous (WF) to obtain five fractions. The chemical profiling of the five fractions was analyzed by ultra-high-performance liquid chromatography coupled with a tandem mass spectrometry (UHPLC-MS/MS), and 18 compounds were tentatively identified. Compared to PF, CF, BF and WF, the EF revealed the highest total phenols (TPC) and total flavonoids (TFC), and displayed the strongest enzyme inhibition ability (α-glucosidase and pancreatic lipase) and antioxidant capacity (DPPH, ABTS and FRAP). Furthermore, these five fractions, especially EF, could effectively inhibit reactive oxygen species (ROS) production and cell apoptosis on H2O2-induced oxidative damage protection in HepG2 cells. This inhibitory effect might be caused by the up-regulation of intracellular antioxidant enzyme activity (CAT, SOD, and GSH). The flavonoids and phenolic acids of V. dunalianum might be the bioactive substances responsible for enzyme inhibitory, antioxidant, and cytoprotective activities. 相似文献