GSTM1与肺癌易感性的病例对照研究

[目的]研究广东人群谷胱甘肽-S-转移酶1(GSTM1)基因多态性和饮酒与肺癌易感性的关系.[方法]采用病例对照研究(病例组91例,对照组138例),调查研究对象的饮酒习惯,应用PCR技术检测GSTM1的基因型.[结果]对照组GSTM1基因频度与肺癌组之间差异无统计学意义,有饮酒习惯者发生肺癌的危险性升高(OR=3.33,P＜0.01).有饮酒习惯及其GSTM1缺陷型的个体,与无饮酒习惯及其GSTM1正常个体相比,明显增加了患肺癌的易感性(OR=5.89,P＜0.01).[结论]饮酒与肺癌有关系,GSTM1缺陷型的饮酒者肺癌危险性增加.     

XRCC1基因多态与肿瘤遗传易感性研究进展

X射线交错互补修复基因1(XRCC1)通过直接与聚合酶β、DNA连接酶Ⅲ和多聚ADP核糖聚合酶形成复合物，共同参与因电离辐射和氧化损伤引起的碱基切除修复和单链断裂修复。XRCC1基因中存在3个单核苷酸多态位点，各位点多态对各种肿瘤遗传易感性的影响不一。现对XRCC1基因多态与某些肿瘤遗传易感性进行综述。     

GENETIC DELETION OF DETOXIFIC ENZYME GSTM1 AND GSTTI AS A HOST SUSCEPTIBLE FACTOR FOR NASOPHARYNGEAL CARCINOMA

Objective: To study the gene polymorphisms of GSTT1 and GSTM1 in nasopharyngeal carcinoma (NPC) patients and controls in an incidental area to evaluate the relationship between specific genotype and genotype combinations of these polymorphisms with the risk of NPC. Methods: Cases and controls all came from the Southwestern Guangxi. DNAs were extracted from their WBC. PCR technique was used to calculate the deletion rate of the two detoxific enzyme genes. Results: In this high risk area of NPC, the residents had high level deletion rates of 47.4% (64/135) Ml and T1 40.7% (55/135). The deletion rates were even higher in NPC patients, 61.5% (56/91) for Ml and 59.3% (54/91) for T1 respectively. There were statistical significances compared with control,P<0.05 andP<0.01 for Ml and T1 respectively. The difference was more significant in terms of combined Ml and T1 deletion between patients and controlsx ²=12.533,P=0.002. Conclusion: The combined deletion of detoxific enzyme genes GSTM1 and GSTT1 may be an important genetic susceptible factor for NPC in Guangxi. Biography: DENG Zhuo-lin (1929-), male, professor of pathology, Guangxi Medical University, majors in tumor pathology. E-mail :zhuolin@hotmail.com     

Methylenetetrahydrofolate Reductase Genotypes, Dietary Habits and Susceptibility to Stomach Cancer

OBJECTIVE To study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dietary habits and the risk of stomach cancer (SC).METHODS A case-control study was conducted with 107 cases of SC and 200 population-based controls in Chuzhou district, Huaian, Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects..MTHFR genotypes were detected by PCR-RFLP. RESULTS (1) The prevalence of the MTHFR C/T or T/T genotypes was found to be significantly different between controls (68.5%) and SC cases (79.4%,P=0.0416), the increased risk had an adjusted OR of 1.79 (95?:1.01-3.19). (2) Among subjects who had a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among non-tea drinkers or among subjects who had a frequent intakeof meat, the carriers of the MTHFR C/T or T/T genotypes had a higher risk of SC than individuals with the C/C type MTHFR. CONCLUSION The polymorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes may have different susceptibilities to SC, based on their exposure level to environmental factors.     

诱发食管癌的可能因素

食管癌是人类常见的一种恶性消化道肿瘤。全球男、女平均死亡率分别为25～50／10万和15～25／10万．严重危害着人们的健康。流行病学资料显示．烟、酒是西欧和北美食管癌发生的主要危险因素．而膳食缺乏维生素、亚硝酸盐含量增高以及食物霉菌污染等可能与亚洲中部地区和中国食管癌发生有关。随着分子生物学的发展．发现     

病毒性心肌炎与铁锌的关系及中医治疗

病毒性心肌炎已成为儿童及青年人常见的心脏疾患。机体在铁锌总量不足时，细胞免疫受到损害，防御能力下降，从而对感染的易感性增加。本文对100例病毒性心肌炎病人血清铁锌含量测定与中医治疗进行了相关研究、探讨，现报道如下。     

细胞色素P450 3A4基因多态性及与肝癌易感性研究

目的 探讨细胞色素P450 3A4(CYP3A4)基因的多态性与肝癌的关系。方法 应用聚合酶链反应（PCR）、变性梯度凝胶电泳（DGGE）、单链构象多态（SSCP）和DNA测序技术，对84例肝癌患者和144例健康对照的CYP3A4基因的多态性进行了研究。结果 通过对CYP3A4基因10个外显子的检测，发现2例肝癌患者的第7外显子第15742位核苷酸发生了A→G转换，使得第183位氨基酸残基由天冬酰胺转变为丝氨酸；发现第10内含子存在一单核苷酸多态，表现第20338位核苷酸发生了G→A转换。病例组G／G、G／A和A／A基因型频率分别为59.52％,36.90%和3.58%；对照组则为59.72%，33.33%和6.95％。两组比较没有统计学差异。结论 CYP3A4基因可能高度保守，虽有突变，但属罕见。     

代谢酶基因多态性与胃癌遗传易感性

肿瘤遗传易感性是目前国内外极其关注的研究领域，不同个体对环境致癌物代谢能力的差异决定了个体对肿瘤的易感性。化学致癌物大多为间接致癌物，需经代谢活化后与细胞生物大分子作用而致癌，经解毒酶作用而失活。毒物代谢过程主要包括两类酶：Ⅰ相酶介导氧化代谢，具有活化作用(包括CYP家族)，Ⅱ相酶具有解毒效应(包括GSTs、     

浅谈艾滋病病毒的口腔科门诊传播

艾滋病是一种潜伏期较长的慢性传染病，人群对其易感性高于99％，感染后治疗难度大，病死率高，对人群健康危害极大。目前中国约有84万艾滋病毒感染者，其中只有5％为艾滋病病人，其余95％为病毒携带者，据国内相关机构的调查，去年，全国艾滋病病毒感染者的增长率达到50％，艾滋病防治已经刻不容缓。