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11.
The ingestion of tea flavonoids (TF) and fructooligosaccharide (FOS) contributes to anti-hyperlipidaemia. In the current study, TF or FOS or TF together with FOS were orally administrated to mice fed a high sucrose (HS) diet. UPLC-MS analyses showed that FOS significantly increased the concentrations of urine catechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate and gallocatechin gallate. The mice fed with HS for continuous 8?weeks exhibited severe dyslipidemia and abnormal liver fat accumulation. However, oral administration of FOS or TF or in combination significantly decreased the effects of HS on the serum total cholesterol, total triglycerides, low-density lipoprotein and high-density lipoprotein. Co-treatment of FOS and TF more effectively regulated lipid metabolism by inhibiting lipogenesis. Intake of TF together with FOS reduced the level of dyslipidemia marker (elaidic acid) by increasing anti-oxidative activity than treatments of FOS or TP alone in HS-fed mice. Histological observations of liver confirmed these health benefits. 相似文献
12.
Tea is popular worldwide with multiple health benefits. It may be contaminated by the accidental introduction of toxigenic fungi during production and storage. The present study focuses on potential mycotoxin contamination in tea and the probable dietary exposure assessments associated with consumption. The contamination levels for 16 mycotoxins in 352 Chinese tea samples were determined by ultra-performance liquid chromatography–tandem mass spectrometry. Average concentrations of almost all mycotoxins in tea samples were below the established regulations, except for ochratoxin A in the dark tea samples. A risk assessment was performed for the worst-case scenarios by point evaluation and Monte Carlo assessment model using the obtained mycotoxin levels and the available green, oolong, black, and dark tea consumption data from cities in China. Additionally, we discuss dietary risk through tea consumption as beverages and dietary supplements. In conclusion, there is no dietary risk of exposure to mycotoxins through tea consumption in the Chinese population. 相似文献
13.
Background Epidemiologic studies have reported inconsistent results regarding tea consumption and the risk of pancreatic cancer. This study aimed to investigate whether tea consumption is related to the risk of pancreatic cancer. Methods We searched Medline, EMBASE, ISI Web of Science, and the Cochrane library for studies published up to November 2013. We used a meta-analytic approach to estimate overall odds ratio (OR) and 95% confidence interval (CO for the highest versus the lowest tea consumption categodes. Results The summary OR for high versus no/almost never tea drinkers was 1.04 (95% CI: 0.91-1.20), with no significant heterogeneity across studies (P=0.751;/2=0.0%). The OR was 0.99 (95% CI: 0.77-1.28) in males and 1.01 (95% CI: 0.79- 1.29) in females. The OR was 1.07 (95% CI: 0.85-1.34) in Asian studies, 1.05 (95% CI: 0.84-1.31) in European studies, and 0.98 (95% CI: 0.72-1.34) in the US studies. The OR was 0.87 (95% CI: 0.69-1.10) without adjustment for a history of diabetes and 1.16 (95% CI: 0.97-0.39) after adjustment for a history of diabetes. The OR was 0.90 (95% CI: 0.72-1.12) without adjustment for alcohol drinking and 1.16 (95% CI: 0.96-1.39) after adjustment for alcohol drinking. The OR was 0.97 (95% CI: 0.76-1.25) without adjustment for BMI and 1.07 (95% CI: 0.87-1.31) after adjustment for BMI. Conclusion This systematic meta-analysis of cohort studies dose not provide quantitative evidence that tea consumption is appreciably related to the risk of pancreatic cancer, even at high doses. 相似文献
14.
Calcineurin and mTOR inhibitors are commonly used immunosuppressive agents with narrow therapeutic range. As the drugs are mainly metabolized by the P450 cytochrome system, the interaction between food and herbs are also commonly seen and affect the drug levels. We present a case of a kidney transplant recipient with toxic therapeutic levels of cyclosporine A and sirolimus due to interaction between the immunosuppressive agents and Chinese herbal tea. Ingredients within the herbal tea were reported to have inhibitory effect on cytochrome CYP3A4 in-vitro studies. Transplant recipients should be alert that there may be potent interaction between the immunosuppressive drugs and herbs resulting in adverse effect on allograft function. 相似文献
15.
16.
目的研究葡茶多酚对尿酸诱导的肾小管上皮细胞TGF-β1表达的影响。方法培养分离肾小管上皮细胞,分对照组、尿酸组、葡茶多酚组(在尿酸干预基础上,分别加入终浓度为0.2、0.4、0.8mg/L的葡茶多酚)共5组,MTT法测细胞增生率、TUNEI。测凋亡率、ELISA测TGF-β1分泌,RT-PCR测TGF-β1mRNA表达。结果与尿酸组相比,加入葡茶多酚干预后,肾小管上皮细胞增生率明显增高(P〈0.01),葡茶多酚干预浓度愈高,肾小管上皮细胞增生率则愈高;葡茶多酚各浓度组在任一时间点凋亡率均明显低于尿酸组,差异有显著意义;葡茶多酚各浓度组之间相比,浓度愈高,则培养细胞凋亡率愈低,差异有显著意义,尿酸作用时间愈长,则培养细胞凋亡率愈高;葡茶多酚各浓度组在任一时间点培养上清TGF-β1浓度均明显降低,差异有显著意义;葡茶多酚各浓度组之间相比,浓度愈高,则培养上清TGF-β1浓度愈低,差异有显著意义,尿酸作用时间愈长,则培养上清TGF-β1浓度愈高;葡茶多酚各浓度组在任一时间点培养上清TGF-β1mRNA表达均明显降低,差异有显著意义;葡茶多酚各浓度组之间相比,浓度愈高,则培养上清TGF-β1mRNA表达愈低,但0.2mg/L葡茶多酚组与0.4mg/L葡茶多酚组、0.4mg/L葡茶多酚组与0.8mg/L葡茶多酚组差异无显著意义,0.2mg/L葡茶多酚组与0.8mg/L葡茶多酚组之间差异有显著意义,尿酸作用时间愈长,则TGF-β1mRNA表达愈高。结论高尿酸能抑制肾小管上皮细胞的增生,减少肾小管上皮细胞的凋亡及TGF-β1的表达与分泌。 相似文献
17.
目的:探讨八段锦联合复方降脂茶对非酒精性脂肪性肝病(non-alcoholic fatty liver disease, NAFLD)患者肝脏脂肪含量,血三酰甘油、低密度脂蛋白、高密度脂蛋白水平的影响。方法:120例NAFLD患者随机分为对照组和观察组各60例。对照组给予常规饮食和运动指导,观察组在对照组干预基础上给予八段锦运动及复方降脂茶。3个月后,比较两组患者肝脏脂肪含量,血三酰甘油、低密度脂蛋白、高密度脂蛋白水平。结果:干预后,观察组患者脂肪含量为(241.65±14.65)dB·mW-1,对照组患者脂肪含量为(259.60±15.91)dB·mW-1,两组患者肝脏脂肪含量比较,差异有统计学意义(P<0.05)。干预后,观察组患者三酰甘油为(2.45±1.04)mmol·L-1,对照组患者三酰甘油为(2.98±1.06)mmol·L-1,两组比较,差异有统计学意义(P<0.05);观察组患者低密度脂蛋白为(3.59±0.59)mmol·L-1,对照组为(4.0... 相似文献
18.
茶多酚对人脐静脉内皮细胞增殖作用的研究 总被引:1,自引:0,他引:1
目的探讨茶多酚(TP)对人脐静脉内皮细胞(HUVEC)生长增殖的影响。方法采用二因素3×5析因设计及噻唑兰(MTT)比色法检测不同作用时间及剂量的仲对HUVEC的生长增殖作用,采用倒置相差显微镜观察HUVEC形态的变化。结果在24h时间段,120,160,240mg/L组,在48,72h时间段,80、120、160、240mg/L组与对照组吸光度有显著性差异。24,48,72h的半数抑制浓度分别是184.41,127.70,108.98mg/L。且TP作用时间与剂量之间有交互作用。结论TP能抑制HUVEC增殖且具有量效一时效依赖关系。 相似文献
19.
绿茶及与相关因素的交互作用对大丰市居民肺癌发生的影响 总被引:4,自引:0,他引:4
目的:分析江苏省恶性肿瘤高发区大丰市人群中绿茶饮用及其与吸烟、饮酒和暴露于烹调油烟等危险因素间交互作用对肺癌发病的影响.方法:在江苏省恶性肿瘤高发区大丰市进行以人群为基础的病例对照研究,共收集523名肺癌病例和1 924 名健康对照,通过面对面询问的方式填写调查表.数据分析采用单因素和调整可能混杂因素的多因素非条件Logistic回归分析.对饮用绿茶与肺癌发病危险之间的关联,以及饮用绿茶与其他危险因素间的交互作用分别进行分析.结果:规律饮用绿茶可使肺癌发病危险显著降低[调整OR值(ORAdj)=0.520,95%可信区间(CI):0.392~0.691];并且肺癌发病危险有随着开始规律饮绿茶年龄减小而降低的趋势(Pfor Trend Adj<0.000 1).交互作用分析显示,规律饮绿茶分别与曾经吸烟、总吸烟量≥30包·年、曾经饮酒以及经常暴露于烹调油烟等因素间存在交互作用,尤其与曾经吸烟和总吸烟量≥30包·年间存在较强的交互作用,其可显著降低吸烟者肺癌的发病危险,ORAdj分别为0.575(95%CI:0.425~0.777)和0.706(95%CI:0.500~0.999).结论:长期规律饮用绿茶对江苏省恶性肿瘤高发地区肺癌高危人群具有明显的保护作用,可以用于肺癌的化学预防. 相似文献
20.
浸泡处理对黄瓜中硝酸盐和亚硝酸盐含量的影响 总被引:1,自引:0,他引:1
目的利用茶溶液对黄瓜进行浸泡处理,根据其对硝酸盐、亚硝酸盐的去除率,探讨最佳浸泡方式。方法利用热水浸提法制备茶叶水溶液,在恒温水浴锅中用茶叶水溶液对黄瓜样品进行浸泡处理,通过改变茶叶水溶液的浓度、浸泡时间、浸泡温度等实验条件,测定黄瓜中硝酸盐、亚硝酸盐的含量变化。结果在温度为30℃时,用浓度为5%的茶溶液对黄瓜浸泡10 min,对其硝酸盐和亚硝酸盐的去除效果较好。结论利用茶溶液做浸泡液对黄瓜中的硝酸盐、亚硝酸盐具有一定的清除效果,但清除率与浸泡条件有关。 相似文献