茶多酚抗牙菌斑作用机理的体外研究

目的研究茶多酚对牙菌斑的影响。方法茶多酚用乙醇，乙酸乙酯从绿茶中提取，并用FeCl3及薄层层析法鉴定，S．sobrinus6715（g）的游离型和结合型GTF分别经硫酸铵和尿素处理获得，Somogyi法测GTF酶活性，染色法测蛋白质含量，葱酮法测葡聚糖含量。通过红外光谱鉴定葡聚糖。结果茶多酚能抑制变链球茵的生长、GTF酶活性及酶产生的胞外多糖。结论茶多酚能有效控制菌斑。     

重复+Gz暴露后大鼠心肌儿茶酚胺类物质含量的变化以及低G预适应和茶多酚的防护作用

目的观察重复+Gz暴露是否引起心肌组织儿茶酚胺类物质代谢异常以及低G预适应和天然抗氧化剂茶多酚(TP)的防护作用. 方法 32只雄性Wistar 大鼠随机分为4组(n=8) A组(对照组),仅受到+1 Gz 作用5 min; B组(+Gz应激组), +10 Gz峰值暴露30 s/次,重复5次/d,间隔为+1 Gz 1 min, 3 d/wk, 共3 wk; C组(低G预适应组), +Gz应激条件同B组,但+10 Gz 暴露前1 h 受到+2 Gz 作用5 min;D组(TP防护组),+Gz应激条件同B组,但+10 Gz 暴露前1 h灌胃给予茶多酚200 mg/kg.于末次+Gz暴露的次日上午将各组大鼠断头处死,迅速摘取心脏置液氮冷藏,用高效液相色谱电化学检测法测定各组大鼠心肌儿茶酚胺类物质含量, 包括去甲肾上腺素(NA),肾上腺素(AD),多巴胺(DA),5-羟色胺(5-HT).结果与A组相比,B组心肌AD水平显著升高(P<0.01),但NA,DA,5-HT含量无明显差别.与B组相比,C、D组心肌AD、5-HT含量明显降低,而D组DA水平显著升高.结论重复+10 Gz暴露引起大鼠心肌儿茶酚胺类物质代谢异常,主要是AD水平显著升高;低G预适应和天然抗氧化剂TP具有明显的防护作用.     

EGCG与肿瘤细胞Wnt信号转导通路的研究进展

<正>表没食子儿茶素没食子酸酯(epigallocatechin gallate,EGCG)是茶叶中一种重要的多酚类物质,约占儿茶素总量的80%,具有抗癌、抗心血管疾病、抗自由基损害、降低低密度胆固醇等作用。     

茶砖加碘防治西藏地区地方性甲状腺肿的疗效观察

本文报告了用茶砖加碘的防治措施在西藏拉萨市郊白定乡进行的 IDD 防治效果的观察。结果表明:经一年多防治后,乡全民患病率由25.6%下降至13.4%,居民尿碘、甲状腺24小时吸~(131)碘率及血清 TSH、T_4水平均恢复正常,这为西藏探索了一条新的 IDD 防治途径。     

The effect of galactagogue herbal tea on oxidant and anti-oxidant status of human milk

Abstract

Objective: Human milk (HM) has antioxidant constituents which protect newborns against oxidative damage. We aimed to evaluate whether maternal consumption of herbal tea containing fenugreek had any effects on global oxidant and antioxidant capacity of HM.

Methods: Volunteer mothers 18–35 years of age without any antenatal or perinatal risk factors were randomly assigned to receive galactagogue herbal tea (Humana still-tee®, Herford, Deutschland) 3 cups/d or same amount of water as placebo. The total antioxidant capacity (TAC), total oxidant status (TOS) and the oxidative stress index (OSI) of breast milk samples taken in the 1st day and 7–10?d were compared between groups.

Results: Herbal tea (n?=?40) and placebo (n?=?40) groups had similar TAC, TOS and OSI values in the 1st day samples. TAC, TOS and OSI values in the breast milk samples taken on 7–10th day were also similar. OSI increased significantly in 7–10 day samples compared to 1st day in each group, while TAC and TOS levels did not differ.

Conclusion: Galactagogue herbal tea containing fenugreek has no detectable effect on global oxidant and antioxidant status of HM. OSI increases in course of lactation compared to colostrums irrespective of galactagogue use.     

A two-stage,single-arm,phase II study of EGCG-enriched green tea drink as a maintenance therapy in women with advanced stage ovarian cancer

Objectives

A two-stage, single-arm, phase II study was conducted to assess the effectiveness and safety of an epigallocatechin gallate (EGCG)-enriched tea drink, the double-brewed green tea (DBGT), as a maintenance treatment in women with advanced stage serous or endometrioid ovarian cancer (clinicaltrials.gov, NCT00721890).

Methods

Eligible women had FIGO stage III-IV serous or endometrioid ovarian cancer. They had to undergo complete response after debulking surgery followed by 6 to 8 cycles of platinum/taxane chemotherapy at the Centre Hospitalier Universitaire de Québec. They all had to drink the DBGT, 500 mL daily until recurrence or during a follow-up of 18 months. The primary endpoint was the absence of recurrence at 18 months. Statistical analyses were done according to the principle of intention to treat. Using a two-stage design, the first stage consisted of 16 enrolled patients. At the end of the follow-up, if 7 or fewer patients were free of recurrence, the trial stopped. Otherwise, accrual would continue to a total of 46 patients.

Results

During the first stage of the study, only 5 of the 16 women remained free of recurrence 18 months after complete response. Accordingly, the clinical trial was terminated. Women's adherence to DBGT was high (median daily intake during intervention, 98.1%, interquartile range: 89.7–100%), but 6 women discontinued the intervention before the end of their follow-up. No severe toxicity was reported.

Conclusions

DBGT supplementation does not appear to be a promising maintenance intervention in women with advanced stage ovarian cancer after standard treatment.     

茶渣中蛋白质酶法提取工艺

研究了蛋白酶法提取茶叶加工后茶渣中蛋白质的工艺。结果显示，碱性蛋白酶和复合蛋白酶提取效果较好；碱性蛋白酶法提取的最佳工艺为酶加量49／6、液固比35：1（mL／g）、提取时间4h，提取率可达34．29，6；复合蛋白酶法提取的最佳提取工艺为酶加量39，6、液固比35：1（mL／g）、提取时间4h，提取率可达18．69／6；双酶法提取中，采用先复合蛋白酶，后碱性蛋白酶，提取效果较好，并且碱性蛋白酶占总酶加量比例对提取率的影响较大，当碱性蛋白酶占25％时，提取率达到最大，为42．19，6；双酶法提取的最佳提取工艺为pH8．0，温度60℃，酶加量49，6，提取率可达47．8％。     

茶叶多糖的研究进展

茶叶多糖是一种复合杂多糖，具有许多生物活性。作者系统地介绍了茶叶多糖的提取、分离、纯化、纯度鉴定及相对分子质量测定的方法，以及其含量和组成、理化性质、化学结构及空间构象、生物活性等方面的研究进展，并对上述方法及研究进展进行了分析和评述。     

Cavernous antioxidant effect of green tea,epigallocatechin‐3‐gallate with/without sildenafil citrate intake in aged diabetic rats

This study aimed to assess the cavernous antioxidant effect of green tea (GT), epigallocatechin‐3‐gallate (EGCG) with/without sildenafil citrate intake in aged diabetic rats. One hundred and four aged male white albino rat were divided into controls that received ordinary chow, streptozotocin (STZ)‐induced aged diabetic rats, STZ‐induced diabetic rats on infused green tea, induced diabetic rats on epigallocatechin‐3‐gallate and STZ‐induced diabetic rats on sildenafil citrate added to EGCG. After 8 weeks, dissected cavernous tissues were assessed for gene expression of eNOS, cavernous malondialdehyde (MDA), glutathione peroxidase (GPx), cyclic guanosine monophosphate (cGMP), and serum testosterone (T). STZ‐induced diabetic rats on GT demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats. Diabetic rats on EGCG demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats or diabetic rats on GT. Diabetic rats on EGCG added to sildenafil showed significant increase in cavernous eNOS, cGMP and significant decrease in cavernous MDA compared with other groups. Serum T demonstrated nonsignificant difference between the investigated groups. It is concluded that GT and EGCG have significant cavernous antioxidant effects that are increased if sildenafil is added.