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91.
BACKGROUND: It has been demonstrated that curcumin can increase the activities of various anti-oxidase in blood and tissue, effectively eliminate various free radicals, reduce the production of peroxisome, and alleviate oxidative stress reaction. Whether it has the same effect on microglia? OBJECTIVE: To observe the effects of curcumin on the expressions of inducible nitric oxide synthase (iNOS), nuclear factor-κB (NF-κB), and superoxide dismutase (SOD) in microglial cell line BV stimulated by lipopolysaccharide (LPS). DESIGN: An observational comparative study. SETTING: Research Room of Biochemistry, Medical College of Nantong University. MATERIALS: Mice microglia cell line BV, iNOS and NF-κB reporter gene plasmids were presented by Dr. Bhat.NR. from the Medical University of South Carolina (USA). Curcumin was produced by the Xi'an Branch of China Chengdu Scholar Bio-Tech. Co.,Ltd.; LPS (E.Coli O26:B6), anti-mice iNOS monoclonal antibody, horseradish peroxidase labeled goat-anti-mice IgG were the products of Sigma Company (USA). METHODS: The experiments were carried out in the Research Room of Biochemistry, Medical College of Nantong University from May 2006 to April 2007. ① Detection of iNOS: The cells were seeded onto 24-well plate at the density of 1×105, After the cells had adhered to the cover glasses, the cells were grouped as negative control group (the primary antibody was replaced by phosphate buffered solution PBS); normal control group (the cells were normally cultured); LPS-treated group (the cells were treated with LPS for 24 hours); curcumin+LPS group (the cells were treated with curcumin for 1 hour and LPS for 24 hours). The expressions of iNOS protein were detected with immunocytochemical staining. ② Determination of iNOS and NF-κB gene activities: According to the introduction of the kit for transfection, iNOS or NF-κB report gene plasmids were transiently transfected with LipofectamineTM2000 liposomes into the cells in the 24-well plate for 24 hours. The cells were divided into normal control group (the cells were normally cultured after transfected with report gene plasmids); blank plasmid group (the cells were normally cultured after transfected with blank plasmids); LPS-treated group (the cells were treated with LPS for 4 hours after transfected with report gene plasmids); curcumin+LPS group (the cells were treated with curcumin for 1 hour and LPS for 24 hours after transfected with report gene plasmids). The content of luciferase in the cell lysis buffer was determined after cell lysis. ③ Determination of SOD activity: The cells were seeded into culture bottle at the density of 1×106, and the divided into four groups, including normal control group (the cells were normally cultured); LPS-treated group (the cells were treated with LPS for 24 hours); curcumin+LPS group (the cells were treated with curcumin for 1 hour and LPS for 24 hours); vitamin C+LPS group (the cells were treated with vitamin C for 1 hour and LPS for 24 hours). The SOD activity was determined with xanthine oxidase and quantitative colorimetric assay. MAIN OUTCOME MEASURES: The expressions of iNOS protein, iNOS and NF-κB, and the activity of SOD were observed. RESULTS: ① Expression of iNOS protein in microglia: The expression of iNOS protein in the LPS-treated group was obviously higher than that in the negative control group (P < 0.01); Those in the curcumin+LPS group were significantly decreased as compared with that in the LPS-treated group (P < 0.01). ② Expressions of iNOS and NF-κB genes: The expressions of iNOS and NF-κB genes in the LPS-treated group were significantly higher than those in the normal control group (P < 0.01); Those in the curcumin+LPS group were significantly lower than those in the LPS-treated group (P < 0.01). ③ SOD activity: The activity of SOD in the LPS-treated group was significantly lower than those in the normal control group (P < 0.01). It in the curcumin+LPS group and vitamin C +LPS group was significantly higher than that in the LPS-treated group (P < 0.01). CONCLUSION: Curcumin could inhibit the expression of iNOS in the activated microglia, and it also has the abilities in eliminating free radicals and antagonizing lipid peroxidation.  相似文献   
92.
Numerous studies document improvements in health status and health expectancies among older adults over time. However, most evidence is from developed nations and gender differences in health trends are often inconsistent. It remains unknown whether changes in health in developing countries resemble Western trends or whether patterns of health improvement are unique to the country's epidemiologic transition and gender norms. Using two nationally representative samples of non-institutionalized adults in China aged 65 years and older, this study investigates gender differences in the improvements in disability, chronic disease prevalence, and self-rated health from 1992 to 2002. Results from multivariate logistic regression models show that all three indicators of health improved over the 10-year period, with the largest improvement in self-rated health. With the exception of disability, the health of women improved more than men. Using Sullivan's decomposition methods, we also show that active life expectancy, disease-free life expectancy, and healthy life expectancy increased over this decade and were patterned differently according to gender. Overall, the findings demonstrate that China experienced broad health improvements during its early stages of the epidemiologic transition and that these changes were not uniform by gender. We discuss the public health implications of the findings in the context of China's rapidly aging population.  相似文献   
93.
无症状性炎性前列腺炎对血清PSA、fPSA的影响   总被引:3,自引:0,他引:3  
目的 探讨无症状性炎性前列腺炎(NIH分类Ⅳ型)对血清PSA、fPSA的影响。方法 对比分析36例NIH分类Ⅳ型、42 例有症状性慢性前列腺炎(NIH分类ⅢA型)患者以及22例健康对照组的血清PSA、fPSA、fPSA/tPSA之间的差异。结果 血 清PSA、fPSA、fPSA/tPSA在Ⅳ型和ⅢA型前列腺炎患者间差异无显著性(P>0.05),但与正常对照组比较差异有显著性(P< 0.01)。结论 NIH分类Ⅳ型前列腺炎可引起血清PSA、fPSA升高。对无症状、高血清PSA患者行前列腺活检前,应考虑到患 Ⅳ型前列腺炎的可能。  相似文献   
94.
CD44v6和组织蛋白酶D表达与食管癌预后的关系   总被引:2,自引:0,他引:2  
目的 研究CD4 4v6和组织蛋白酶D(cathepsinD ,CD)表达与食管癌生物学行为的关系。方法 应用免疫组化法 ,检测 6 5例食管鳞状细胞癌组织中CD4 4v6和CD表达水平。结果 在食管癌中CD4 4v6和CD表达阳性率分别为 5 8.5 %和 6 4 .6 %。CD4 4v6和CD表达均与肿瘤分级、浸润、淋巴结转移和预后相关。结论 CD4 4v6和CD异常表达与食管癌的病理生物学行为密切相关 ,可作为是预测食管癌转移潜能和评估食管癌预后的客观指标  相似文献   
95.
Ⅰ型纤溶酶原激活物抑制剂(PAI-1)是一种Mr为50×103的单链糖蛋白,有379个氨基酸残基,3个N型糖基化位点。构建PAI-1糖基化突变体,以便研究糖链的功能。用寡核苷酸定位突变技术将3个糖基化位点209,265,329位进行突变,把3个糖基化位点都发生了突变的PAI-1cDNA组装到真核表达载体pSV2中,得到真核表达质粒pZH-p1-M3E;在二氢叶酸还原酶缺陷型中国仓鼠卵巢细胞(CHOdhfr-)中进行短暂表达,用发色底物法和夹心ELISA方法检测培养液中PAI-1的活性和含量。结果:糖基化位点突变的PAI-1能在CHO细胞中表达,但表达水平及活性较低。非糖基化PAI-1的活性和抗原分别为4.34IU/ml和3.15μg/L结论:用寡核苷酸定位突变方法获得了PAI-1糖基化突变体,并且在CHO细胞中得到表达。  相似文献   
96.
Laryngeal cancer represents an important cause of cancer in France, and the individual effects of alcohol and tobacco on this cancer site are well known. However the problem of the interaction between these agents is less extensively documented, and the role of the high consumptions of alcohol has not been studied frequently. A case-control analysis was undertaken to investigate the joint effect of alcohol and tobacco by comparing 197 glottic and 214 supraglottic cancer cases to 4135 controls representative of the French general population. Heavy drinkers were available from the two groups of cases, the highest alcohol category being equivalent to a consumption of more than 2 litres of wine per day. The relative risks estimated for heavy drinkers and smokers were high, and the results indicated an even stronger effect of alcohol drinking and tobacco smoking on the upper part of the laryngeal region. Additive and multiplicative models were fitted to the data. The multiplicative hypothesis was found to be the most appropriate, implying that the risks associated with alcohol and tobacco multiply when the exposures occur simultaneously. The public health implications of this result and the contribution of heavy drinkers and smokers to the frequency of upper respiratory and digestive tract cancers are discussed.  相似文献   
97.
本文对夹竹桃甙抑制Na~+、K~+-ATP酶的动力学作了探讨,并与乌本甙的作用进行了比较。结果表明:夹竹桃甙抑制Na~+、K~+-ATP酶,在Na~+、K~+浓度改变对均为非竞争性抑制,Na~+/K~+比例6:1时,为混合性抑制,而ATP对夹竹桃甙的作用几无影响。  相似文献   
98.
This is first report about the simultaneous over-expression of both Insulin-like growth factor (IGF-II) and its receptor (IGF-II R) at mRNA level in human primary hepatic Cancer (PHC). In 10 PHC samples from China, IGF-II and IGF-II R were both over-expressed, whereas only a background signal was detected in normal liver. In 5 pairs of PHC and its non-tumorous adjacent liver tissues from South Africa, IGF-II and IGF-II R were also over-expressed in PHC. mRNA expression of IGF-II in all 5 cases and IGF-II R in 4 of 5 cases were higher in cancer than non-tumorous adjacent liver tissues. These results strongly implicate that an autocrine and/or paracrine mechanism might be involved in formation and progression of PHC.  相似文献   
99.
A tissue equivalent phantom was used in the study and absored x-ray doses.It measuring for some important organs of head and neck by four routive sialography methods (panoramic conventional x-ray radioagraphy,tomography,fluoroscope,CT) and also the X-ray absorbed doses of thyroid and len when lead containing loop and spectacles of head containing glass were used for prevention.All the data were processed statistically and a compartive study of absorbed x-ray doses of four sialography methods:Doses of submandibular gland were higher in CT,tomography and fluoroscope among them,CT was the highest indicating that it was superior to other methods for accurately locating that it was superior to other methods for accurately locating the within-gland tumor.Fluoroscope will be use more frequently in clinic,because it can observe the living gland panoramic and normal radiography can be used routinely because they had the minimum doses in measured organs.2.The absorbed x-ray doses of len and thyroid decreased by 93%-% when prevention was taken in CT or fluoroscope,65%-85% doses was decreased in normal radiography or panoramic with prevention.  相似文献   
100.
煤烟型大气污染对儿童肺功能的影响   总被引:4,自引:1,他引:3  
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。  相似文献   
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