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991.
Shaowei Li Xuhua Tang J. Seetharaman Chunyan Yang Ying Gu Jun Zhang Hailian Du J. Wai Kuo Shih Choy-Leong Hew J. Sivaraman Ningshao Xia 《PLoS pathogens》2009,5(8)
Hepatitis E virus (HEV), a non-enveloped, positive-stranded RNA virus, is transmitted in a faecal-oral manner, and causes acute liver diseases in humans. The HEV capsid is made up of capsomeres consisting of homodimers of a single structural capsid protein forming the virus shell. These dimers are believed to protrude from the viral surface and to interact with host cells to initiate infection. To date, no structural information is available for any of the HEV proteins. Here, we report for the first time the crystal structure of the HEV capsid protein domain E2s, a protruding domain, together with functional studies to illustrate that this domain forms a tight homodimer and that this dimerization is essential for HEV–host interactions. In addition, we also show that the neutralizing antibody recognition site of HEV is located on the E2s domain. Our study will aid in the development of vaccines and, subsequently, specific inhibitors for HEV. 相似文献
992.
Yuling Xiao Wenjin Xu Qifeng Zhu Bingfang Yan Dongfang Yang Jin Yang Xianran He Shucai Liang Xianming Hu 《Carbohydrate polymers》2009,77(3):612-620
In this investigation, the fabrication, physico-chemical and biological characterization of a novel smart hydrogel had been evaluated for its potentials in effective controlling protein delivery. The hydrophilic pachyman-based hydrogel was generated facilely by crosslinking hydrosoluble carboxymethyl pachyman (CMP) with epichlorohydrin (ECH). The ECH concentration possessing maximum (99.7%) encapsulation efficiency and the most appropriate swelling characteristics was found to be 1.25% (w/v). The resultant hydrogel exhibited swelling ratios most favorable for drug release in simulated intestinal media. It could release two model protein drugs (bovine serum albumin and lysozyme) in the controlled manner and with full preservation of the protein stability and enzymatic activity. Importantly, the ECH-CMP hydrogel was confirmed to be biocompatible and biodegradable. From these findings, we were able to conclude that the synthesized pachyman-based hydrogel would be a promising delivery carrier candidate for site-specific delivery of protein drugs. 相似文献
993.
994.
Song-sheng Shi Wei-zhong Yang Ye Chen Jian-ping Chen Xian-kun Tu 《Neurochemical research》2014,39(5):793-799
Our previous studies demonstrated that inflammatory reaction and neuronal apoptosis are the most important pathological mechanisms in ischemia-induced brain damage. Propofol has been shown to attenuate ischemic brain damage via inhibiting neuronal apoptosis. The present study was performed to evaluate the effect of propofol on brain damage and inflammatory reaction in rats of focal cerebral ischemia. Sprague–Dawley rats underwent permanent middle cerebral artery occlusion, then received treatment with propofol (10 or 50 mg/kg) or vehicle after 2 h of ischemia. Neurological deficit scores, cerebral infarct size and morphological characteristic were measured 24 h after cerebral ischemia. The enzymatic activity of myeloperoxidase (MPO) was assessed 24 h after cerebral ischemia. Nuclear factor-kappa B (NF-κB) p65 expression in ischemic rat brain was detected by western blot. Cyclooxygenase-2 (COX-2) expression in ischemic rat brain was determined by immunohistochemistry. ELISA was performed to detect the serum concentration of tumor necrosis factor-α (TNF-α). Neurological deficit scores, cerebral infarct size and MPO activity were significantly reduced by propofol administration. Furthermore, expression of NF-κB, COX-2 and TNF-α were attenuated by propofol administration. Our results demonstrated that propofol (10 and 50 mg/kg) reduces inflammatory reaction and brain damage in focal cerebral ischemia in rats. Propofol exerts neuroprotection against ischemic brain damage, which might be associated with the attenuation of inflammatory reaction and the inhibition of inflammatory genes. 相似文献
995.
Hukui Sun Guangjie Yang Ting Liang Chao Zhang Jing Song Jiankui Han Guihua Hou 《Journal of cellular and molecular medicine》2014,18(12):2437-2444
Although 18F‐fluorodeoxyglucose (18F‐FDG) uptake can be used for the non‐invasive detection and monitoring of allograft rejection by activated leucocytes, this non‐specific accumulation is easily impaired by immunosuppressants. Our aim was to evaluate a 131I‐radiolabelled anti‐Toll‐like receptor 5 (TLR5) mAb for non‐invasive in vivo graft visualization and quantification in allogeneic transplantation mice model, compared with the non‐specific radiotracer 18F‐FDG under using of immunosuppressant. Labelling, binding, and stability studies were performed. BALB/c mice transplanted with C57BL/6 skin grafts, with or without rapamycin treatment (named as allo‐treated group or allo‐rejection group), were injected with 131I‐anti‐TLR5 mAb, 18F‐FDG, or mouse isotype 131I‐IgG, respectively. Whole‐body phosphor‐autoradiography and ex vivo biodistribution studies were obtained. Whole‐body phosphor‐autoradiography showed 131I‐anti‐TLR5 mAb uptake into organs that were well perfused with blood at 1 hr and showed clear graft images from 12 hrs onwards. The 131I‐anti‐TLR5 mAb had significantly higher graft uptake and target‐to‐non‐target ratio in the allo‐treated group, as determined by semi‐quantification of phosphor‐autoradiography images; these results were consistent with ex vivo biodistribution studies. However, high 18F‐FDG uptake was not observed in the allo‐treated group. The highest allograft‐skin‐to‐native‐skin ratio (A:N) of 131I‐anti‐TLR5 mAb uptake was significantly higher than the ratio for 18F‐FDG (7.68 versus 1.16, respectively). 131I‐anti‐TLR5 mAb uptake in the grafts significantly correlated with TLR5 expression in the allograft area. The accumulation of 131I‐IgG was comparable in both groups. We conclude that radiolabelled anti‐TLR5 mAb is capable of detecting allograft with high target specificity after treatment with the immunosuppressive drug rapamycin. 相似文献
996.
Chun-Nan Lin A-Mei Huang Kai-Wei Lin Tzyh-Chyuan Hour Horng-Huey Ko Shyh-Chyun Yang Yeong-Shiau Pu 《Phytochemistry》2010,71(17-18):2140-2146
The diterpenoids (+)-ferruginol (1), ent-kaur-16-en-15-one (2), ent-8(14),15-sandaracopimaradiene-2α,18-diol (3), 8(14),15-sandaracopimaradiene-2α,18,19-triol (4), and (+)-sugiol (5) and the triterpenoids 3β-methoxycycloartan-24(241)-ene (6), 3β,23β-dimethoxycycloartan-24(241)-ene (7), 3β,23β-dimethoxy-5α-lanosta-24(241)-ene (8), and 23(S)-23-methoxy-24-methylenelanosta-8-en-3-one (9), isolated from Amentotaxus formosana, showed inhibitory effects on xanthine oxidase (XO). Of the compounds tested, compound 5 was a potent inhibitor of XO activity, with an IC50 value of 6.8 ± 0.4 μM, while displaying weak ABTS radical cation scavenging activity. Treatment of the bladder cancer cell line, NTUB1, with 3–10 μM of compound 5 and 10 μM cisplatin, and immortalized normal human urothelial cell line, SV-HUC1, with 0.3–1 μM and 10–50 μM of compound 5 and 10 μM cisplatin, respectively, resulted in increased viability of cells compared with cytotoxicity induced by cisplatin. Treatment of NTUB1 with 20 μM cisplatin and 10 or 30 μM of compound 5 resulted in decreased ROS production compared with ROS production induced by cisplatin. These results indicate that 10 or 30 μM of compound 5 in NTUB1 cells may mediate through the suppression of XO activity and reduction of reactive oxygen species (ROS) induced by compound 5 cotreated with 20 μM cisplatin and protection of subsequent cell death. 相似文献
997.
Angus G. Scrimgeour Louis J. Marchitelli Jered S. Whicker Yang Song Emily Ho Andrew J. Young 《The Journal of nutritional biochemistry》2010,21(7):653-658
Phytic acid forms insoluble complexes with nutritionally essential minerals, including zinc (Zn). Animal studies show that addition of microbial phytase (P) to low-Zn diets improves Zn status and bone strength. The present study determined the effects of phytase supplementation on bone mineral density (BMD), body composition and voluntary running activity of male rats fed a high phytic acid, low-Zn diet. In a factorial design, rats were assigned to ZnLO (5 mg/kg diet), ZnLO+P (ZnLO diet with 1500 U phytase/kg) or ZnAD (30 mg/kg diet) groups and were divided into voluntary exercise (EX) or sedentary (SED) groups, for 9 weeks. SED rats were significantly heavier from the second week, and no catch-up growth occurred in EX rats. Feed intakes were not different between groups throughout the study. ZnLO animals had decreased food efficiency ratios compared to both phytase-supplemented (ZnLO+P) and Zn-adequate (ZnAD) animals (P<.01 compared to ZnLO). The ZnLO+P and ZnAD rats ran 56–75 km more total distance than ZnLO rats (P<.05), with the ZnLO+P rats running more kilometers per week than the ZnLO rats by Week 6. In vivo DEXA analyses indicate that rats fed phytase-supplemented diets had higher lean body mass (LBM) than those fed ZnLO diets; and that rats fed the Zn-adequate diets had the highest LBM. Body fat (%) was significantly lower in EX rats and was both Zn- and phytase insensitive. Rats fed phytase-supplemented diets had higher bone mineral content (BMC), bone area (BA) and BMD than rats fed ZnLO diets; and in rats fed ZnAD diets these indices were the highest. The dietary effects on BMC, BA and BMD were independent of activity level.We conclude that consuming supplemental dietary phytase or dietary Zn additively enhances Zn status to increase BMD, LBM and voluntary physical activity in rats fed a low-Zn diet. While the findings confirm that bone health is vulnerable to disruption by moderate Zn deficiency in rats, this new data suggests that if dietary Zn is limiting, supplemental phytase may have beneficial effects on LBM and performance activity. 相似文献
998.
Haifeng Tang Yan Yan Zhe Feng Reynalda K. de Jesus Lihu Yang Dorothy A. Levorse Karen A. Owens Taro E. Akiyama Raynald Bergeron Gino A. Castriota Thomas W. Doebber Kenneth P. Ellsworth Michael E. Lassman Cai Li Margaret S. Wu Bei B. Zhang Kevin T. Chapman Sander G. Mills Joel P. Berger Alexander Pasternak 《Bioorganic & medicinal chemistry letters》2010,20(20):6088-6092
A new series of thiazole-substituted 1,1,1,3,3,3-hexafluoro-2-propanols were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Key analogs caused dose-dependent decreases in food intake and body weight in obese mice. Acute treatment with these compounds also led to a drop in elevated blood glucose in a murine model of type II diabetes. 相似文献
999.
Huang-Yao Tu A-Mei Huang Tzyh-Chyuan Hour Shyh-Chyun Yang Yeong-Shiau Pu Chun-Nan Lin 《Bioorganic & medicinal chemistry》2010,18(6):2089-2098
A series of novel 2′,5′-dimethoxylchalcone derivatives including 18 new compounds were synthesized and evaluated for cytotoxicities against two human cancer cell lines, NTUB1 (human bladder cancer cell line) and PC3 (human prostate cancer cell line). All these derivatives except for 21 exhibited significant cytotoxic effect against NTUB1 and PC3 cell lines. Compounds 13 and 17 with 4-carbamoyl moiety showed potent inhibitory effect on growth of NTUB1 and PC3 cells. Flow cytometric analysis demonstrated that treatment of NTUB1 cells with 1 μM 13 and 17 induced G1 phase arrest accompanied by an increase in apoptotic cell death of NTUB1 cells after 24 h. Treatment of PC3 cells with 1 μM and 3 μM 13, and 1 μM and 3 μM 17 induced S and G1, and G1 and G2/M phase arrests, respectively, accompanied by an increase in apoptotic cell death. These data suggested that 13 and 17 with different 4-carbamoyl moiety displayed same cell cycle arrest in NTUB1 cells while different doses of 13 and 17 revealed different cell cycle arrest in PC3 cells. Cell morphological study of 17 indicated that more cells rounding up or dead associated with tubulin polymerization. Compound 17 showed an increased α-tubulin level in polymerized microtubule fraction in a dose-dependent manner while 500 nM paclitaxel also showed similar effect in NTUB1 cells by Western blot analysis. The result suggested that 17 may be used as microtubule-targeted agents. 相似文献
1000.