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91.
Huihuan Wu Sha Tu Zewei Zhuo Rui Jiang Ruijie Zeng Qi Yang Qizhou Lian Weihong Sha Hao Chen 《Molecules (Basel, Switzerland)》2023,28(1)
Ulcerative colitis is a chronic inflammatory bowel disorder that is hard to cure once diagnosed. Bisdemethoxycurcumin has shown positive effects on inflammatory diseases. However, the underlying bioactive interaction between bisdemethoxycurcumin and ulcerative colitis is unclear. The objective of this study was to determine the core target and potential mechanism of action of bisdemethoxycurcumin as a therapy for ulcerative colitis. The public databases were used to identify potential targets for bisdemethoxycurcumin and ulcerative colitis. To investigate the potential mechanisms, the protein-protein interaction network, gene ontology analysis, and Kyoto encyclopedia of genes and genomes analysis have been carried out. Subsequently, experimental verification was conducted to confirm the findings. A total of 132 intersecting genes of bisdemethoxycurcumin, as well as ulcerative coli-tis-related targets, were obtained. SRC, EGFR, AKT1, and PIK3R1 were the targets of highest potential, and the PI3K/Akt and MAPK pathways may be essential for the treatment of ulcerative colitis by bisdemethoxycurcumin. Molecular docking demonstrated that bisdemethoxycurcumin combined well with SRC, EGFR, PIK3R1, and AKT1. Moreover, the in vitro experiments suggested that bisdemethoxycurcumin might reduce LPS-induced pro-inflammatory cytokines levels in RAW264.7 cells by suppressing PI3K/Akt and MAPK pathways. Our study provided a comprehensive overview of the potential targets and molecular mechanism of bisdemethoxycurcumin against ulcerative colitis. Furthermore, it also provided a theoretical basis for the clinical treatment of ulcerative colitis, as well as compelling evidence for further study on the mechanism of bisdemethoxycurcumin in the treatment of ulcerative colitis. 相似文献
92.
针对水中、空气中脉冲放电条件下金属电极烧蚀速率及烧蚀机理差异,对脉冲大电流作用下水中、空气中钨铜电极的烧蚀特性进行了对比研究。在保证放电电流波形一致性的前提下,通过采用高精度天平测量并获取了水中、空气中钨铜电极的阴、阳极烧蚀速率及总烧蚀速率,并对电极表面进行了二次电子观察和背散射电子观察分析。结果表明,大脉冲电流作用下,水中钨铜电极烧蚀较空气中更为严重,钨铜电极的烧蚀主要是金属蒸发引起的汽相侵蚀。由于水介质较空气具有不可压缩性,水中放电电弧集中,电极表面电弧斑点处电流密度和电流作用时间较空气中更为严重,同时由于水中脉冲放电时发生的高温物理化学反应,是造成水中电极烧蚀要高于空气中的根本原因。 相似文献
93.
Chang-Sheng Zhang Ya-Ping Shao Fu-Min Zhang Xue Han Xiao-Ming Zhang Kun Zhang Yong-Qiang Tu 《Chemical science》2022,13(28):8429
A novel classical kinetic resolution of 2-aryl-substituted or 2,3-disubstituted cyclobutanones of Baeyer–Villiger oxidation catalyzed by a Cu(ii)/SPDO complex is reported for the first time, producing normal lactones in excellent enantioselectivities (up to 96% ee) and regioselectivities (up to >20/1), along with unreacted ketones in excellent enantioselectivities (up to 99% ee). The current transformation features a wide substrate scope. Moreover, catalytic asymmetric total syntheses of natural eupomatilones 5 and 6 are achieved in nine steps from commercially available 3-methylcyclobutan-1-one.A novel classical kinetic resolution of Baeyer–Villiger oxidation catalyzed by a Cu(ii)/SPDO complex with excellent enantioselectivity, regioselectivity and wide substrate scope is reported for the first time and explore the synthetic application. 相似文献
94.
Bin-Long Sun Ying-Ying Wang Sen Yang Min-Ting Tu Ying-Ying Shao Yi Hua Yi Zhou Cheng-Xia Tan 《Molecules (Basel, Switzerland)》2022,27(12)
To develop new compounds with high activity, broad spectrum and low-toxicity, 17 benzamides substituted with quinoline-linked 1,2,4-oxadiazole were designed using the splicing principle of active substructures and were synthesized. The biological activities were evaluated against 10 fungi, indicating that some of the synthetic compounds showed excellent fungicidal activities. For example, at 50 mg/L, the inhibitory activity of 13p (3-Cl-4-Cl substituted, 86.1%) against Sclerotinia sclerotiorum was superior to that of quinoxyfen (77.8%), and the inhibitory activity of 13f (3-CF3 substituted, 77.8%) was comparable to that of quinoxyfen. The fungicidal activities of 13f and 13p to Sclerotinia sclerotiorum were better than that of quinoxyfen (14.19 mg/L), with EC50 of 6.67 mg/L and 5.17 mg/L, respectively. Furthermore, the acute toxicity of 13p was 19.42 mg/L, classifying it as a low-toxic compound. 相似文献
95.
96.
光纤布拉格光栅自致啁啾效应的研究 总被引:3,自引:0,他引:3
根据耦合模理论,采用传输矩阵法分析了相位掩模法制作的光纤布拉格光栅的反射谱特性.设计了一种新的写制光纤光栅的光路,利用高斯激光光束写制出具有短波自致啁啾效应的切趾光栅(栅长0.015 m).对具有短波自致啁啾效应的光纤光栅进行了物理切割(剩余光栅的长度分别取0.007 m和0.0055 m),得到了一种新型的具有长波自致啁啾效应的光纤光栅.原本的自致啁啾光栅反射谱中旁瓣分布在短波长方向,而得到的新型自致啁啾光栅的反射谱中长波长方向的旁瓣更为明显.基于对光纤布拉格光栅自致啁啾效应的分析,提出一种新型类高斯切趾函数,以此函数对自致啁啾效应进行数值模拟,得到了与实验结果相一致的光谱图. 相似文献
97.
The evaluation and interpretation of the behavior of construction materials under fire conditions have been complicated. Over the last few years, artificial intelligence (AI) has emerged as a reliable method to tackle this engineering problem. This review summarizes existing studies that applied AI to predict the fire performance of different construction materials (e.g., concrete, steel, timber, and composites). The prediction of the flame retardancy of some structural components such as beams, columns, slabs, and connections by utilizing AI-based models is also discussed. The end of this review offers insights on the advantages, existing challenges, and recommendations for the development of AI techniques used to evaluate the fire performance of construction materials and their flame retardancy. This review offers a comprehensive overview to researchers in the fields of fire engineering and material science, and it encourages them to explore and consider the use of AI in future research projects. 相似文献
98.
治疗胆石症蒙药苏斯-12中多种元素的ICP-AES法测定及分析 总被引:3,自引:0,他引:3
通过分析治疗胆囊炎、胆石症的蒙药苏斯—12中微量元素含量,探讨蒙药苏斯—12的药效与微量元素含量的关系。应用高压密封微波消解、电感耦合等离子体原子发射光谱法(ICP-AES)对蒙药苏斯—12进行微量元素含量分析。在蒙药的配制及整体研究工作中发现它们含有多种氨基酸和丰富的微量元素,实验结果表明:苏斯—12中含有丰富的微量元素,尤其Ca,Al,Mg,Fe,Sr,Mn,Zn,Cu等元素的含量比较高,而Pb,Cd,As等元素含量相对低,都低于国家限定值。加标回收率在94.63%~106.40% 之间,相对标准偏差RSD≤3.35 %,检出限在≤0.009 μg·L-1。蒙药苏斯—12有效控制和治疗胆囊炎、胆石症,总有效率达91.2%和100%,蒙药苏斯—12中的微量元素与药效之间有密切的关系。 相似文献
99.
100.