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81.
Nguyen Phuong Thao Le Duc Dat Ninh Thi Ngoc Vu Anh Tu Tran Thi Hong Hanh Phan Thi Thanh Huong Nguyen Xuan Nhiem Bui Huu Tai Nguyen Xuan Cuong Nguyen Hoai Nam Pham Van Cuong Seo Young Yang Sohyun Kim Doobyeong Chae Young-Sang Koh Phan Van Kiem Chau Van Minh Young Ho Kim 《Bioorganic & medicinal chemistry letters》2013,23(6):1823-1827
Three new pyrrole oligoglycosides, astebatheriosides A–C (1–3), and a new furan oligoglycoside, astebatherioside D (4), were isolated from the starfish Asterina batheri by various chromatographic methods. Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, and 4 moderately inhibited IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC50 values of 36.4, 31.6, and 22.8 μM, respectively. 相似文献
82.
Tae-Hwan Ha HyungChul Ryu Sung-Eun Kim Ho Shin Kim Jihyae Ann Phuong-Thao Tran Van-Hai Hoang Karam Son Minghua Cui Sun Choi Peter M. Blumberg Robert Frank Gregor Bahrenberg Klaus Schiene Thomas Christoph Sven Frormann Jeewoo Lee 《Bioorganic & medicinal chemistry》2013,21(21):6657-6664
A series of 2-thio pyridine C-region analogues of 2-(3-fluoro-4-methylsulfonylaminophenyl)propanamides were investigated as hTRPV1 antagonists. Among them, compound 24S showed stereospecific and excellent TRPV1 antagonism of capsaicin-induced activation. Further, it demonstrated strong anti-allodynic in a rat neuropathic pain model. Consistent with its action in vitro being through TRPV1, compound 24S blocked capsaicin-induced hypothermia in mice. Docking analysis of 24S with our hTRPV1 homology model was performed to identify its binding mode. 相似文献
83.
Phuong-Thao Tran Van-Hai Hoang Shivaji A. Thorat Sung Eun Kim Jihyae Ann Yu Jin Chang Dong Woo Nam Hyundong Song Inhee Mook-Jung Jiyoun Lee Jeewoo Lee 《Bioorganic & medicinal chemistry》2013,21(13):3821-3830
In an effort to design inhibitors of human glutaminyl cyclase (QC), we have synthesized a library of N-aryl N-(5-methyl-1H-imidazol-1-yl)propyl thioureas and investigated the contribution of the aryl region of these compounds to their structure–activity relationships as cyclase inhibitors. Our design was guided by the proposed binding mode of the preferred substrate for the cyclase. In this series, compound 52 was identified as the most potent QC inhibitor with an IC50 value of 58 nM, which was two-fold more potent than the previously reported lead 2. Compound 52 is a most promising candidate for future evaluation to monitor its ability to reduce the formation of pGlu-Aβ and Aβ plaques in cells and transgenic animals. 相似文献
84.
Bo Li Ankita Umapathy Loi Uyen Tran Paul J. Donaldson Julie C. Lim 《Histochemistry and cell biology》2013,139(4):559-571
The aim of this study is to determine the contribution of the ciliary epithelium to glutathione (GSH) levels in the aqueous by mapping GSH metabolism and transport pathways in the rat ciliary body. Using a combination of molecular and immunohistochemical techniques, we screened and localised enzymes and transporters involved in GSH synthesis, uptake, efflux and degradation. Our findings indicate that both the pigmented epithelial (PE) and the non-pigmented epithelial (NPE) cell layers are capable of accumulating precursor amino acids for GSH synthesis, but only the NPE cells appear to be involved in the direct uptake of precursor amino acids from the stroma. The localisation of GSH efflux transporters to the PE cell and PE–NPE interface indicates that GSH and potentially GSH-S conjugates can be removed from the ciliary epithelium into the stroma, while the location of GSH efflux transporters to the basolateral membrane of the NPE indicates that these cells can mediate GSH secretion into the aqueous. GSH secreted by the ciliary into the aqueous would remain largely intact due to the absence of the GSH degradation enzymes γ-glutamyltranspeptidase (γ-GGT) labelling at the basolateral membrane of the NPE. Therefore, it appears that the ciliary epithelium contains the molecular machinery to mediate GSH secretion into the aqueous. 相似文献
85.
Bacterial cultures were enriched from sediments in Germany and Vietnam reductively dechlorinating hexachlorobenzene and the highly persistent 1,3,5-trichlorobenzene to monochlorobenzene. The main products of the reductive dechlorination of hexachlorobenzene were monochlorobenzene and dichlorobenzenes (1,2-; 1,3- and 1,4-dichlorobenzene) while no trichlorobenzenes accumulated. For the reductive dechlorination of 1,3,5-trichlorobenzene with the mixed culture from Vietnam sediment, 1,3- dichlorobenzene and monochlorobenzene were produced as intermediate and final end-product, respectively. The pattern of dechlorination did not change when the cultures were repeatedly exposed to oxygen over seven transfers demonstrating oxygen tolerance of the dechlorinating bacteria. However, reductive dechlorination of 1,3,5-trichlorobenzene was inhibited by vancomycin at a concentration of 5 mg L?1. Vancomycin delayed reductive dechlorination of hexachlorobenzene in mixed cultures by about 6 months. When repeatedly applied, vancomycin completely abolished the ability of the mixed culture to transform hexachlorobenzene. Sensitivity to vancomycin and insensitivity to brief exposure of oxygen indicates that the dechlorinating bacteria in the mixed cultures did not belong to the genus Dehalococcoides. 相似文献
86.
Chantal Sellier Fernande Freyermuth Ricardos Tabet Tuan Tran Fang He Frank Ruffenach Violaine Alunni Herve Moine Christelle Thibault Adeline Page Flora Tassone Rob Willemsen Matthew D. Disney Paul J. Hagerman Peter K. Todd Nicolas Charlet-Berguerand 《Cell reports》2013,3(3):869-880
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87.
Chengrong Huang Juntao Kan Xu Liu Fenfen Ma Ba Hieu Tran Yunzeng Zou Shujun Wang Yi Zhun Zhu 《PloS one》2013,8(7)
Objective
Heart failure (HF) is one of the most serious diseases worldwide. S-propargyl-cysteine (SPRC), a novel modulator of endogenous hydrogen sulfide, is proved to be able to protect against acute myocardial ischemia. In order to produce more stable and sustainable hydrogen sulfide, we used controlled release formulation of SPRC (CR-SPRC) to elucidate possible cardioprotective effects on HF rats and investigate involved mechanisms on apoptosis and oxidation.Methods
Left coronary artery was occluded to induce HF model of rat. The survival rats were randomly divided into 7 groups after 24 hours and treated with drugs for 6 weeks. Echocardiographic indexes were recorded to determine cardiac function. TTC staining was performed to determine infarct size. Plasmatic level of hydrogen sulfide was detected by modified sulfide electrode. Activity of enzyme and expression of protein were determined by colorimetry and Western blot, respectively.Results
The cardioprotective effects of CR-SPRC on HF rats were confirmed by significant reduction of infarct size and improvement of cardiac function, with better effects compared to normal SPRC. CR-SPRC modulated antioxidant defenses by preserving levels of GSH, CAT and SOD and reducing CK leakage. In addition, CR-SPRC elevated ratio of Bcl-2/Bax and inhibited activity of caspases to protect against myocardial apoptosis. The cardioprotective effects of CR-SPRC were mediated by hydrogen sulfide.Conclusions
All experiment data indicated cardioprotective effects of CR-SPRC on HF rats. More importantly, CR-SPRC exerted better effects than normal SPRC in all respects, providing a new perspective on hydrogen sulfide-mediated drug therapy. 相似文献88.
MNK Clottey R Asmah PK Ofori-Danson MY Ameworwor AY Karikari 《African Journal of Aquatic Science》2016,41(4):473-480
The effects of cage fish farming on physico-chemical and bacteriological water quality in Lake Volta, Ghana, were investigated in 2013–2014. Farmed and unfarmed (control) areas of the lake were selected for monitoring. Nutrients, temperature, dissolved oxygen, conductivity, turbidity, pH, total coliforms, Pseudomonas and Vibrio spp. in the water were monitored monthly. Analyses of the water samples were carried out according to standard procedures. Physico-chemical quality of the water in both farm and control sites were within ranges typical of minimally impacted water and did not vary significantly between the two contrasting sites. The bacteriological analysis, however, revealed contamination of the lake water by fish farming. The bacterial counts at the farmed sites were significantly higher (p < 0.05) than those of the control sites, with figures at the farmed sites ranging from 132 to 1 708 cfu 100 ml?1 for total coliforms, 514 to 5 170 cfu 100 ml?1 Pseudomonas spp. and 14 to 516 cfu 100 ml?1 for Vibrio spp. The results suggested that cage fish farming has increased bacterial loads in the lake water, but has had minimal impact on its physico-chemical quality. 相似文献
89.
An allosteric antibody to the leptin receptor reduces body weight and reverses the diabetic phenotype in the Lepob/Lepob mouse
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90.