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101.
Wei Tian Guangqian Han Ju Zhu Jingjing Qi Qianqian Chen Juntao Zhao Canhui Zheng Ling Zhang Youjun Zhou Jiaguo Lv 《Bioorganic & medicinal chemistry letters》2013,23(14):4177-4184
A series of novel 5-phenyl-1H-pyrazole-3-carboxylic acid amide derivatives were designed, synthesized, and their acrosin inhibitory activities in vitro were evaluated. The results of the acrosin inhibitory activity showed that all target compounds were more potent than control TLCK. Compounds AQ-A1, AQ-D3, AQ-D4, AQ-E4 and AQ-E5 exhibited stronger acrosin inhibitory activities than control ISO-1. Especially, compound AQ-E5 displayed the most potent acrosin inhibitory activity in all the compounds, with an IC50 of 0.01 μmol/mL. This study provided a new structural class for the development of novel acrosin inhibitory agents. 相似文献
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103.
Nan Zhang Zhen Song Yuhua Xie Ping Cui Hongxia Jiang Tao Yang Ruicheng Ju Yuhua Zhao Jinyu Li Xunli Liu 《World journal of microbiology & biotechnology》2013,29(8):1443-1452
An antifungal Actinomyces BS-112 strain, with Aspergillus flavus as the target pathogen, was isolated from soil in the forest land of Mountain Tai. This strain showed a strong antagonistic activity against various mold fungi in food and feed. Strain BS-112 was identified as Streptomyces hygroscopicus based on its morphologic, cultural, physiological, biochemical characteristics, cell wall components and 16S rDNA sequence. Four active components were separated and purified from strain BS-112. These four antifungal components were identified as tetrins A and B and tetramycins A and B using spectroscopic analysis including mass spectrometry and nuclear magnetic resonance spectroscopy. Tetrins A and B and tetramycins A and B strongly inhibited the growth of A. flavus, A. alutaceus, A. niger, and A. fumigatus in vitro. 相似文献
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Adhesion molecules such as ICAM-1 are important in the infiltration of leukocytes into the site of inflammation. In this study, we investigated the inhibitory effects of curcumin on ICAM-1 expression and monocyte adhesiveness as well as its underlying action mechanism in the TNF-α-stimulated keratinocytes. Curcumin induced expression of heme oxygenase-1 (HO-1) in the human keratinocyte cell line HaCaT. In addition, curcumin induced Nrf2 activation in dose- and time-dependent manners in the HaCaT cells. Curcumin suppressed TNF-α- induced ICAM-1 expression and subsequent monocyte adhesion, which were reversed by the addition of tin protoporphyrin IX (SnPP), a specific inhibitor of HO-1, or HO-1 knockdown using siRNA. Furthermore, Nrf2 knockdown using siRNA reversed the inhibitory effect of curcumin on the TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that curcumin may exert its anti-inflammatory activity by suppressing the TNF-α-induced ICAM-1 expression and subsequent monocyte adhesion via expression of HO-1 in the keratinocytes. [BMB Reports 2013;46(8): 410-415] 相似文献
107.
The matrix metalloproteinases (MMPs) are well known to responsible for the degradation of extracellular matrix (ECM) during tissue remodelling such as wound healing, metamorphosis, and regeneration. In present study, gelatinase activities were investigated in normal and retinoic acid (RA)-treated limb regenerates. During the early phase of limb regeneration, gelatinase activities increased greatly, and RA caused the enhanced and prolonged gelatinase activities. We also isolated full length of Hynobius MMP-9, and its spatial and temporal expression profiles were examined in normal, RA-treated, and denervated limb regenerates. Whole mount in situ hybridization showed that the expression of MMP-9 increased in the wound epidermis at the wound healing stage and early phase of dedifferentiation stage. In addition, RA enhanced remarkably its expression both in terms of level and duration in the wound epidermis. However, expression signal of MMP-9 was barely detectable in denervated in limb regenerates. Our results may indicate that MMP-9 plays important role(s) in the dedifferentiation process by participating in ECM degradation and enhancement of MMP-9 expression and activity might be closely related to RA-evoked pattern duplication. 相似文献
108.
Rhamnolipids are high‐value effective biosurfactants produced by Pseudomonas aeruginosa. Large‐scale production of rhamnolipids is still challenging especially under free‐cell aerobic conditions in which the highly foaming nature of the culture broth reduces the productivity of the process. Immobilized systems relying on oxygen as electron acceptor have been previously investigated but oxygen transfer limitation presents difficulties for continuous rhamnolipid production. A coupled system using immobilized cells and nitrate instead of oxygen as electron acceptor taking advantage of the ability of P. aeruginosa to perform nitrate respiration was evaluated. This denitrification‐based immobilized approach based on a hollow‐fiber setup eliminated the transfer limitation problems and was found suitable for continuous rhamnolipid production in a period longer than 1,500 h. It completely eliminated the foaming difficulties related to aerobic systems with a comparable specific productivity of 0.017 g/(g dry cells)‐h and allowed easy recovery of rhamnolipids from the cell‐free medium. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 346–351, 2013 相似文献
109.
自20世纪60年代初发现细胞老化以来,关于细胞老化的研究有了长足的进展。"Hay-flick极限(Hayflick limit)"概念的确立不仅在细胞水平揭示了细胞寿命的重要分子机制,而且拓展了人们对于衰老(aging)的认识。近年来,越来越多的实验结果表明,细胞老化可以在体内有效阻止癌症的发生,尤其在癌症早期具有明显作用。该文就半个多世纪以来,关于人们认知的细胞老化的基本特征、判别标准以及相关研究进展予以综述。 相似文献
110.
Ronghai Deng Guangxiang Gu Dongping Wang Qiang Tai Linwei Wu Weiqiang Ju Xiaofeng Zhu Zhiyong Guo Xiaoshun He 《PloS one》2013,8(3)