氯乙烯对雄性大鼠生殖内分泌激素的影响

目的 探讨氯乙烯对雄性大鼠生殖内分泌激素的影响.方法 雄性SD大鼠60只,随机分为对照组和10、100和1000mg/kg氯乙烯染毒组,每组15只,腹腔注射染毒14和28d.测定大鼠血清中睾酮(T)、卵泡刺激素(FSH)、黄体生成素(LH)、雌二醇(E2)、抑制素B(InhB)和睾丸中E2、T、InhB的水平,并观察睾丸支持细胞和间质细胞超微结构的改变.结果 与对照组比较,染毒14 d各染毒组大鼠血清中T和E2水平降低,InhB和LH水平升高,仅100 mg/kg染毒组LH水平差异有统计学意义(P<0.05).染毒28 d,100、1000 mg/kg染毒组大鼠血清中T分别为(10.90±1.56)和(8.52±2.85)ng/ml,InhB水平分别为(31.40±6.21)和(28.39±5.67)pg/ml,均明显低于对照组[T为(15.89±4.03)ng/ml,lnhB为(46.87±8.74)pg/ml],差异有统计学意义(P<0.05);各染毒组大鼠血清中FSH水平均明显高于对照组.差异有统计学意义(P<0.05).与染毒14d比较,染毒28d各染毒组大鼠血清中InhB和LH水平均明显降低,差异有统计学意义(P<0.05).染毒28 d时100、1000mg/kg染毒组大鼠睾丸组织中T和InhB水平分别为(8.05±2.19)、(6.75±1.94)ng/mg pro和(39.32±5.55)、(35.53±8.71)pg/mg pro,与对照组[T为(11.90±2.33)ng/mg pro、InhB为(49.45±7.01)pg/mg pro]比较,差异有统计学意义(P<0.05).超微结构观察可见,染毒组的睾丸间质细胞和支持细胞出现了细胞核畸形、线粒体肿胀等改变.结论 氯乙烯对雄性大鼠生殖内分泌系统有损害作用,可引起生殖内分泌激素水平改变和睾丸间质细胞、支持细胞超微结构变化.     

Polymorphisms for vinyl chloride metabolism in French vinyl chloride workers

Genetic polymorphisms of aldehyde dehydrogenase 2 (ALDH2) and cytochrome P450 2E1 (CYP2E1) have been shown to influence the degree of genetic damage in Taiwanese workers exposed to the carcinogen - vinyl chloride(VC). Certain French VC workers have been found to express biomarkers of mutant forms of cancer-related proteins (ras-p21 and p53) that have been related to their exposure. ALDH2 and CYP2E1 polymorphisms were investigated in 211 of these workers in an attempt to correlate differences in VC metabolic capacity with differences in the presence of these biomarkers. All of the workers were found to have the normal, wild-type ALDH2 gene, and none of them were found to be homozygous for the variant CYP2E1 allele. Sixteen workers were found to be heterozygous for the variant CYP2E1 allele. After adjusting for age, smoking, drinking and cumulative VC exposure, the odds ratio for the presence of either the mutant ras-p21 or the mutant p53 biomarker in these heterozygous workers was found to be statistically significantly increased in comparison to their homozygous, wild-type counterparts (OR = 5.05; 95% CI = 1.10-23.25). However, as opposed to the case in Taiwanese workers, these polymorphisms are relatively uncommon, and thus differences in ALDH2 and CYP2E1 can account for only a small proportion of the variability in mutagenic response to VC exposure in a Caucasian population.     

Mitochondrial changes in hepatocytes of rats chronically exposed to vinyl chloride and ethanol

Chronic exposure of male rats to 600 ppm vinyl chloride (VC) or VC and 5% ethanol (EtOH) in drinking water induced ultrastructural changes in the mitochondria of hepatocytes. After 6 months of $\text{VC}\text{EtOH}$ treatment, hepatocyte mitochondria often contained rigid tubular parallel cristae and dilated cristae with dense inclusions; ethanol ingestion alone did not induce these morphological changes. In animals receiving VC alone, large floccular densities in the mitochondrial matrix were seen occasionally after 6 months of VC inhalation. The numbers and severity of changes in mitochondria increased with duration of exposure and age. The greatest responses observed in mitochondria occurred with the combined treatment of $\text{VC}\text{EtOH}$.     

多糖联合对辐照大鼠睾丸组织损伤保护作用

目的 探讨枸杞多糖(LBP)和海带多糖(LJP)联合作用对慢性电离辐射致大鼠睾丸组织氧化损伤的影响.方法 将4周雄性Wistar大鼠随机分为对照组、模型组、LBP组、LJP组和LBP+LJP联合组;灌胃7 d后进行连续4周(周六、周日除外)60Coy照射,剂量2.3 Gy/只,照射期间每天灌胃;照射结束7d后进行组织切片观察睾丸形态改变,测定睾丸组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和还原型谷胱甘肽(GSH)、丙二醛(MDA)含量.结果 对照组MDA含量为(1.30±O.27)nmol/mg,与模型组、LBP组、LJP组的(2.16±0.34),(1.86±0.29),(1.70±0.09)nmol/mg比较,差异均有统计学意义(P＜0.Ol或P＜0.05);LBP+LJP联合组MDA含量为(0.82±0.34)nmoL/mg,与模型组比较,差异有统计学意义(P＜0.01);对照组SOD活力为(155.11±4.49)U/mg,与模型组、LBP组、LJP组的(123.98±11.38),(137.60±7.38),(133.54±8.89)U/mg比较,差异均有统计学意义(P＜0.01).结论 LBP+LJP联合作用对电离辐射致睾丸组织损伤具有明显的保护作用,其效果优于LBP、LJP单独作用.     

氯乙烯中毒1例报告

FGC-A^＋型全自动肺功能测试仪采用先进的微电脑处理系统,通过呼吸流量传感器,测量出人体的呼气功能和吸气功能,再经过分析,处理,由液晶显示器（LCD）显示和图形打印机打印结果.     

氯乙烯致肝损伤与毒物代谢酶基因多态性的关系

目的 探讨毒物代谢酶基因多态性与接触氯乙烯致肝损伤的关系。方法 以肝B－超检查异常或丙氨酸转氨酶（ALT）＞40作为肝损伤指标,应用聚合酶链反应（PCR）检测谷胱甘肽转移酶（GSTT1,GSTM1）基因型;应用PCR和限制性酶切片段长度多态分析技术（RFLP）检测细胞色素P4502E1酶基因型（CYP2E1）,然后对实验结果进行统计分析。结果 尽管GSTT1基因型分布在肝损伤组与对照组比较,差异均无显著性（P＞0．05）。当将低、中接触组合并后,阳性型肝损组与对照组比较,差异有显著性（OR为0．35,95％CI为0．12－0．97,P＜0．05）;在高接触损伤组,CYP2E1组比较,差异有显著性（OR为0．35,95％CI为0．12－0．97,P＜0．05）;在高接触损伤组,CYP2E1clc2/c2c2基因型有更高的频率,与对照组比较,差异有显著性（OR为4．55,95％CI为1．37－15．08,P＜0．05）,多元Logistic回归分析显示,CYP2E1基因型、氯乙烯接触与CYP2E1基因型,CYP2E1与GSTT1基因型,GSTT1与GSTM1基因型间的联合作用与肝脏损伤有关联,经χ^2检验,P＜0．05。结论 高剂量接触氯乙烯时,CYP2E1、clc2/c2c2基因型在氯乙烯致肝损伤方面可能是主要感性原因之一,而GSTT1在氯乙烯代谢中可起到解毒作用,尤其在低剂量接触时有保护作用。本研究结果初步表明,毒物代谢酶基因间联合作用与累积接触剂量,最终决定毒物是否产生危害。氯乙烯接触所致肝脏损伤,是由接触剂量以及个体的遗传特性所共同决定的。     

Nonneoplastic effects of vinyl chloride in mouse lung

In a previous study, a high incidence of pulmonary tumors (alveologenic neoplasia in mouse lung exposed to vinyl chloride at heavy dose (2500 and 6000 ppm) for long durations (5 and 6 months) was reported (Y. Suzuki, 1978, Environ. Res.16, 285–301). In the present study, nonneoplastic effects in mouse lung were investigated by light and electron microscopy. As major light microscopic alterations, proliferation and hypertrophy of the terminal bronchiolar cells, consisting of ciliated and Clara cells, hypersecretion of the epithelial mucin in the goblet cells of both the bronchial and the proximal bronchiolar epithelium, hyperplasia of alveolar epithelium, mobilization of alveolar macrophages, and occasional presence of peribronchial or bronchiolar chronic inflammation, were observed. Electron microscopically, Clara cells of the terminal bronchiolar epithelium showed proliferation of the rough and smooth surfaced endoplasmic reticulum and appearance of large and abnormally shaped mitochondria. Similar alterations were found in the ciliated cells. Submicroscopic changes of pulmonary alveoli were represented by focal thickening of the basement membrane, multiple foci of hyperplastic type II cell (the precondition of the alveologenic tumor), active discharge of osmiophilic lamellar bodies from the type II cell and phagocytosis of the bodies by macrophages, appearance of cholesterol crystalloids in the macrophages, degeneration of alveolar septal cells and occasional appearance of a large nucleus with swelling of the capillary endothelium.     

五味子乙素对汞性大鼠急性肾损伤的影响

目的探讨五味子乙素(Sch B)对汞致大鼠急性肾损伤的影响。方法 Wistar大鼠30只,按体重随机分成5组:第1组为正常对照组,第2~4组分别为低、中、高剂量单纯染汞组,第5组为Sch B预处理组。对照组和单纯染汞组空腹以大豆油灌胃,Sch B预处理组16 mg/kg Sch B空腹灌胃,灌胃容量为5 ml/kg;2 h后,对照组皮下注射生理盐水,低、中、高剂量单纯染汞组分别皮下注射2.2μmol/kg、4.4μmol/kg、8.8μmol/kg氯化汞,Sch B预处理组皮下注射8.8μmol/kg氯化汞,注射容量为5 ml/kg。第二日重复上述操作,并将大鼠放入代谢笼,收集24 h尿液;而后将大鼠乙醚麻醉,腹主动脉采血,切取大鼠肾皮质,测定尿汞和肾皮质汞,尿β-N-乙酰氨基葡萄糖苷酶(NAG)、尿乳酸脱氢酶(LDH)及尿碱性磷酸酶(ALP)活力,尿蛋白和血尿素氮(BUN)含量,肾皮质还原型谷胱甘肽(GSH)和丙二醛(MDA)含量,超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力。结果与对照组比较,高剂量氯化汞组尿汞和肾皮质汞含量,尿NAG、LDH及ALP活力,尿蛋白和BUN含量,GSH和M...     

氯乙烯染毒大鼠DNA损伤与肝脏某些生化指标的变化

目的　研究氯乙烯 (VCM)对大鼠肝细胞和血淋巴细胞DNA的损伤作用 ,及肝脏某些生化指标的变化。方法　DNA损伤采用单细胞凝胶电泳 (彗星实验 )法 ,代谢酶活性采用分光光度法 ,肝功能测定使用自动生化分析仪。结果　彗星发生率染毒组显著高于对照组 ,肝细胞和血淋巴细胞彗星发生率显著相关。结论　VCM可导致大鼠肝细胞和血淋巴细胞DNA发生损伤 ,且存在剂量 效应 反应关系。     

氯乙烯作业工人肝脏功能损伤的影响因素研究

目的 探讨氯乙烯作业工人肝脏功能损伤的影响因素.方法 以肝B超检查异常或丙氨酸转氨酶(ALT)≥40U作为肝损伤指标,结合历年体检资料,对遗传因素(氯乙烯代谢酶基因多态性)、生活习惯(吸烟、饮酒)、氯乙烯作业等影响因素进行统计学处理分析.结果 多元Logistic分析和秩和检验显示细胞色素P450 2E1(CYP2E1)基因型、饮酒与氯乙烯作业工人肝功能损伤有关.Spearman等级相关分析显示,日均氯乙烯吸入量与肝功能ALT值成正相关.结论 氯乙烯工人肝功能损伤情况受遗传、生活习惯、氯乙烯作业综合影响,对氯乙烯工人的健康监护应全面考虑.     

Incidence of cancer among vinyl chloride and polyvinyl chloride workers.

The results of a follow up study of the incidence of cancer and the mortality in a cohort of 454 male workers producing vinyl chloride and polyvinyl chloride are presented. The study population was restricted to employees with more than one year's work experience in the study plant between 1950 and 1969 and the cohort was followed up from 1953 to the end of 1979. Twenty three new cases of cancer were observed compared with 20.2 expected; one case of liver angiosarcoma was found. Five cases of lung cancer were found (2.8 expected) and four cases of malignant melanoma of the skin were observed (0.8 expected). The possibility of a causal relationship between exposure to vinyl chloride and the development of malignant melanomas is discussed.