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101.
Lipid deposition in the kidney can cause serious damage to the kidney, and there is an obvious epithelial–mesenchymal transition (EMT) and fibrosis in the late stage. To investigate the interventional effects and mechanisms of phenolic compounds from Mori Cortex on the EMT and fibrosis induced by sodium oleate-induced lipid deposition in renal tubular epithelial cells (NRK-52e cells), and the role played by CD36 in the adjustment process, NRK-52e cells induced by 200 μmol/L sodium oleate were given 10 μmoL/L moracin-P-2″-O-β-d-glucopyranoside (Y-1), moracin-P-3′-O-β-d-glucopyranoside (Y-2), moracin-P-3′-O-α-l-arabinopyranoside (Y-3), and moracin-P-3′-O-[β-glucopyranoside-(1→2)arabinopyranoside] (Y-4), and Oil Red O staining was used to detect lipid deposition. A Western blot was used to detect lipid deposition-related protein CD36, inflammation-related protein (p-NF-κB-P65, NF-κB-P65, IL-1β), oxidative stress-related protein (NOX1, Nrf2, Keap1), EMT-related proteins (CD31, α-SMA), and fibrosis-related proteins (TGF-β, ZEB1, Snail1). A qRT-PCR test detected inflammation, EMT, and fibrosis-related gene mRNA levels. The TNF-α levels were detected by ELISA, and the colorimetric method was used to detects SOD and MDA levels. The ROS was measured by flow cytometry. A high-content imaging analysis system was applied to observe EMT and fibrosis-related proteins. At the same time, the experiment silenced CD36 and compared the difference between before and after drug treatment, then used molecular docking technology to predict the potential binding site of the active compounds with CD36. The research results show that sodium oleate can induce lipid deposition, inflammation, oxidative stress, and fibrosis in NRK-52e cells. Y-1 and Y-2 could significantly ameliorate the damage caused by sodium oleate, and Y-2 had a better ameliorating effect, while there was no significant change in Y-3 or Y-4. The amelioration effect of Y-1 and Y-2 disappeared after silencing CD36. Molecular docking technology showed that the Y-1 and Y-2 had hydrogen bonds to CD36 and that, compared with Y-1, Y-2 requires less binding energy. In summary, moracin-P-2″-O-β-d-glucopyranoside and moracin-P-3′-O-β-d-glucopyranoside from Mori Cortex ameliorated lipid deposition, EMT, and fibrosis induced by sodium oleate in NRK-52e cells through CD36.  相似文献   
102.
In order to seek novel technetium-99m folate receptor-targeting agents, two folate derivatives (CN5FA and CNPFA) were synthesized and radiolabeled to obtain [99mTc]Tc-CN5FA and [99mTc]Tc-CNPFA complexes, which exhibited high radiochemical purity (>95%) without purification, hydrophilicity, and good stability in vitro. The KB cell competitive binding experiments indicated that [99mTc]Tc-CN5FA and [99mTc]Tc-CNPFA had specificity to folate receptor. Biodistribution studies in KB tumor-bearing mice illustrated that [99mTc]Tc-CN5FA and [99mTc]Tc-CNPFA had specific tumor uptake. Compared with [99mTc]Tc-CN5FA, the tumor/muscle ratios of [99mTc]Tc-CNPFA were higher, resulting in a better SPECT/CT imaging background. According to the results, the two 99mTc complexes have potential as tumor imaging agents to target folate receptors.  相似文献   
103.
In the presence of Cp2LnX-HgCl2, the treatment of RC identical to CCH2Br with Mg leads to the formation of benzene derivatives C6H4R2-1,2 (R = H, Ph) in moderate yield, which provides a new method for the construction of the benzene ring skeleton.  相似文献   
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106.
The phase diagrams of four binary systems (C10H21NH3)2CoCl4?(C16H33NH3)2CoCl4, (C12H25NH3)2CoCl4?(C16H33NH3)2CoCl4, (C10H21NH3)2ZnCl4?(C16H33NH3)2ZnCl4 and (C12H25NH3)2ZnCl4?(C16H33NH3)2ZnCl4 were investigated by means of DSC. These six compounds and their binary mixtures can retain energies between 74 and 115 J/g during solid-state transformations at temperatures between 70 and 105°C, and they are therefore being considered for potential use in solar energy systems.  相似文献   
107.
Xanthatin, a natural sesquiterpene lactone, has significant antitumor activity against a variety of cancer cells, yet little is known about its anticancer mechanism. In this study, we demonstrated that xanthatin had obvious dose-/time-dependent cytotoxicity against the human non-small-cell lung cancer (NSCLC) cell line A549. Flow cytometry analysis showed xanthatin induced cell cycle arrest at G2/M phase. Xanthatin also had pro-apoptotic effects on A549 cells as evidenced by Hoechst 33258 staining and annexin V-FITC staining. Mechanistic data revealed that xanthatin downregulated Chk1, Chk2, and phosphorylation of CDC2, which contributed to the cell cycle arrest. Xathatin also increased total p53 protein levels, decreased Bcl-2/Bax ratio and expression of the downstream factors procaspase-9 and procaspase-3, which triggered the intrinsic apoptosis pathway. Furthermore, xanthatin blocked phosphorylation of NF-κB (p65) and IκBa, which might also contribute to its pro-apoptotic effects on A549 cells. Xanthatin also inhibited TNFa induced NF-κB (p65) translocation. We conclude that xanthatin displays significant antitumor effects through cell cycle arrest and apoptosis induction in A549 cells. These effects were associated with intrinsic apoptosis pathway and disrupted NF-κB signaling. These results suggested that xanthatin may have therapeutic potential against NSCLC.  相似文献   
108.
The induced aggregation of achiral building blocks by a chiral species to form chiral aggregates with memorized chirality has been observed for a number of systems. However, chiral memory in isolated aggregates of achiral building blocks remains rare. One possible reason for this discrepancy could be that not much is understood in terms of designing these chiral aggregates. Herein, we report a strategy for creating such isolable chiral aggregates from achiral building blocks that retain chiral memory after the facile physical removal of the chiral templates. This strategy was used for the isolation of chiral homoaggregates of neutral achiral π-conjugated carboxylic acids in pure aqueous solution. Under what we have termed an "interaction-substitution" mechanism, we generated chiral homoaggregates of a variety of π-conjugated carboxylic acids by using carboxymethyl cellulose (CMC) as a mediator in acidic aqueous solutions. These aggregates were subsequently isolated from the CMC templates whilst retaining their memorized supramolecular chirality. Circular dichroism (CD) spectra of the aggregates formed in the acidic CMC solution exhibited bisignated exciton-coupled signals of various signs and intensities that were maintained in the isolated pure homoaggregates of the achiral π-conjugated carboxylic acids. The memory of the supramolecular chirality in the isolated aggregates was ascribed to the substitution of COOH/COOH hydrogen-bonding interaction between the carboxylic acid groups within the aggregates for the hydrogen-bonding interactions between the COOH groups of the building blocks and the chiral templates. We expect that this "interaction-substitution" procedure will open up a new route to isolable pure chiral aggregates from achiral species.  相似文献   
109.
无烟煤结构的高分辨电镜研究   总被引:1,自引:0,他引:1  
镜质组不仅是煤结构变化最具规律性,也是影响煤质的主要微成分。用点分辨率为2.1A的高分辨电镜对几种不同煤化程度的无烟煤大分子结构进行了研究。结果表明:电镜图像直接表征了无烟煤分子的非均匀性孔隙结构。京西煤分子方向化程度强,主要以芳层平行堆或有序化前结构为主;晋城煤方向化程度弱,主要以粒状嵌晶结构为主。高分辨电镜技术是研究煤分子结构和煤化作用实质的有效方法。  相似文献   
110.
用停流FIA-分光光度法研究了铬(Ⅵ)-碘化钾动力学反应体系中铁(Ⅱ)和钒(Ⅳ)的协同诱导效应,以协同系数(D)表示二者相互作用程度的大小,在此基础上提出了一种新的动力学双组份同时测定的方法,本法可扩大前述方法的线性范围,并降低检测限,测定了模拟水样品中铁和钒的含量,结果满意。  相似文献   
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