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991.
ZHAO Xue-rong WANG Jian-ping XIAO Li-jun XU Qian ZHAO En-hong ZHENG Xin ZHENG Hua-chuan ZHAO Shuang 《园艺学报》2015,31(1):98-103
AIM: To investigate the effects of 17-AAG on apoptosis and cell cycle of HCT-15 cells and to clarify the related mechanisms. METHODS: MTT method was employed to evaluate the inhibitory effects of 17-AAG with Aifferent time and different doses on the proliferation of HCT-15 cells. The cells were stained with Annexin V-FITC/propidiumiodide and measured by flow cytometry. The expression of STAT3, cyclin D1, Cyt C, caspase 9 and caspase 3 at mRNA and protein levels was determined by RT-PCR and Western blotting. RESULTS: Treatment with 17-AAG at concentration of 1.25~20 mg/L for 24 h and 48 h significantly inhibited the activity of HCT-15 cells at both time-and concentration-dependent manners. Treatment with 17-AAG at concentrations of 0.425, 0.85 and 1.7 mg/L for 48 h significantly induced apoptosis and cell cycle arrest of HCT-15 cells. The exposure of 17-AAG at concentrations of 0.425, 0.85 and 1.7 mg/L for 48 h to the HCT-15 cells significantly down-regulated the expression of STAT3 and cyclin D1 at mRNA and protein levels, but up-regulated Cyt C, caspase 9 and caspase 3 mRNA and protein in a concentration-dependent manner. CONCLUSION: 17-AAG inhibits the cell activity, induces apoptosis and G1 arrest by down-regulating the expression of cyclin D1, and promoting the mitochondria apoptosis through STAT3 pathway. 相似文献
992.
993.
HUANG Hua LI Yu-sheng JIN Xin WANG Jiang-tao LI Na HUANG Zhen-gui DING Bo-ping 《园艺学报》2015,31(8):1365-1370
AIM: To investigate the effect of rhynchophylline (Rhy) on blood pressure, cardiac hypertrophy and myocardial fibrosis in spontaneously hypertensive rats (SHR). METHODS: Spontaneously hypertensive rats were randomly divided into model group, high dose (10 mg·kg-1·d-1) and low dose (2.5 mg·kg-1·d-1) group of rhynchophylline, captopril group (17.5 mg·kg-1·d-1). Wistar-Kyoto rats were used as normal control. Respectively, systolic blood pressure was measured by tail cuff every 2 weeks. After 10 weeks, heart weight index and left ventricular weight index were calculated. The myocardial hydroxyproline and plasma angiotensin Ⅱ were detected. Moreover, basic myocardial histopathological changes and myocardial collagen fibres were observed by HE staining and Masson staining, respectively. The protein expression of TGF-β1 and Smad3 in the myocardium was measured by the methods of immunohistochemistry and Western blot. RESULTS: Compared with SHR model group, Rhy significantly reduced blood pressure (P<0.05), the levels of HYP in the myocardium (P<0.05) and the levels of AngⅡ in the plasma (P<0.01). The pathological damages of the myocardial tissues and collagen deposition were attenuated. The protein expression of TGF-β1 and Smad3 was significantly reduced by the treatment with Rhy (P<0.01). CONCLUSION: Rhynchophylline reduces blood pressure and adjusts to improve ventricular remodeling of SHR. The mechanism may be involved in the TGF-β1/Smad pathway and reducing AngⅡ content. 相似文献
994.
AIM: To investigate the effects of BARF1 down-regulation on EBV-positive gastric carcinoma cell apoptosis, and the molecular mechanisms by BARF1 silencing-mediated apoptosis. METHODS: After NUGC3 and SNU719 cells were transfected with NCsiRNA and siRNA, respectively, the protein levels of BARF1, Bcl-2, Bax, cytochrome C, caspase 3 and capase 9 were detected by Western blot, and the mRNA expression of BARF1, Bcl-2 and Bax was determined by RT-PCR. The cell viability was measured by the method of Trypan blue exclusion and the cell apoptosis was analyzed by flow cytometry analysis with Annexin V-FITC/PI staining. The expression of the apoptosis-related proteins in the cells transfected with siRNA and NCsiRNA was examined by human apoptosis antibody arrays. Mitochondrial membrane potential was determined by flow cytometry. The interaction between Apaf-1 and caspase 9 was confirmed by immunoprecipitation. RESULTS: Compared with untreated and NCsiRNA groups, BARF1 gene silencing significantly inhibited the cell viability, induced apoptosis, and reduced the mitochondrial membrane potential in the NUGC3 and SNU719 cells transfected with siRNA. BARF1 gene silencing up-regulated the expression of pro-apoptotic proteins and down-regulated the expression of anti-apoptotic proteins, and the Bcl-2/Bax ratio was significantly decreased. In BARF1 gene silencing cells, the caspase inhibitor z-VAD-fmk inhibited BARF1 silencing-mediated apoptosis, and significantly increased the levels of cleaved caspase 3 and caspase 9. The concentration of cytochrome C significantly increased as compared with NCsiRNA group, and Apaf-1 interacted with caspase 9 in the cytoplasm. CONCLUSION: BARF1 silencing induces apoptosis via the mitochondrial pathway through regulating the expression of Bcl-2 and Bax proteins in a caspase-dependent manner in the NUGC3 and SNU719 cells. 相似文献
995.
996.
997.
广西二十种金花茶观赏价值综合评价 总被引:1,自引:0,他引:1
运用层次分析法(AHP)建立了金花茶观赏价值的综合评价体系,从叶、花、果、其它特性4个方面筛选出13个评价指标,并用yaahp层次分析法软件V0.6.0计算了评价体系中各指标的权重,采用综合评价法对20种金花茶进行了评价。结果表明:进行评价的20种金花茶可分为3个等级,Ⅰ级(分值≥3.6227)观赏价值极高的6种金花茶;Ⅱ级(2.8424~3.2222)观赏价值较高的6种金花茶;Ⅲ级(2.4939~2.6639)有一定观赏价值的8种金花茶。 相似文献
998.
以"红富士"苹果为试材,采用无菌蒸馏水、1%海藻酸钠、0.5%海藻酸钠+0.1%生姜提取液、1%海藻酸钠+0.1%生姜提取液4个处理,PE保鲜袋4℃下贮藏,研究了生姜提取液及其可食性复合膜对鲜切"红富士"苹果的贮藏品质的影响。结果表明:海藻酸钠+生姜提取液处理在阻止水分蒸腾,维持硬度,降低褐变程度,减少营养物质的损耗,抑制多酚氧化酶(PPO)活性和丙二醛(MDA)的积累,减少微生物侵染方面,其综合效果要优于仅用海藻酸钠涂膜的处理及无菌蒸馏水处理的鲜切苹果。通过模糊数学感官评价方法对不同处理的鲜切苹果进行评判,得出最佳组合为1%海藻酸钠+0.1%生姜提取液。 相似文献
999.
1000.