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261.
慢性有机磷农药接触对羧基酯酶活力的影响 总被引:4,自引:0,他引:4
目的 酯酶不仅在有机磷农药解毒中发挥重要作用 ,而且与心血管疾病有密切关系。我们研究3种酯酶 (丁酰胆碱酯酶BchE、羧酸酯酶CarbE和对氧磷酶PonE)的酶活力在一般人群中的特点 ,探讨有机磷农药慢性接触对酶活力的影响 ,为其他研究提供基线资料。方法 选取 10 0名无有机磷农药接触的对照人群和 75名长期接触有机磷农药的生产工人 ,检测外周血酯酶活力 ,描述正常成人酶活力的特点 ,分析有机磷接触对酯酶活力的影响。结果 对照人群BchE均值为 (78 3± 30 4 )mmol/(ml·h) ;CarbE均值为(36 2 7± 195 0 )nmol/(ml·min) ;PonE均值为 (332 6± 96 2 )nmol/(ml·min)。 3种酶活力在人群中均呈正态分布。有机磷农药接触工人BchE活力为 (2 7 3± 2 1 7)mmol/(ml·h) ;CarbE活力为 (2 35 6± 10 4 0 )nmol/(ml·min) ;PonE活力为 (30 7 8± 10 7 0 )nmol/(ml·min)。结论 3种酯酶活力无年龄和性别差异。有机磷接触工人的BchE和CarbE活力与对照人群比较 ,差异有显著性 ,说明有机磷能抑制BchE和CarbE活力 ,而对对氧磷酶活力无抑制作用。提示 ,BchE和CarbE活力可以作为反映有机磷农药接触 相似文献
262.
263.
《亚太热带病杂志(英文版)》2014
ObjectiveTo evaluate paraoxonase activity, antioxidant status and lipid peroxidation in hypertensive participants and to address the hypothesis that oxidative modifications of lipids due to hypertension can cause changes in serum paraoxonase activities.MethodsThe serum paraoxonase activities, antioxidants and lipid peroxidation were determined in 130 hypertensive participants and 130 age-sexes matched normotensive healthy volunteers served as control. Serum paraoxonase activities were measured by enzymatic kit. The glutathione peroxidase, superoxide dismutase and catalase activity were determined by standard methods. Malondialdehyde was measured by thiobarbituric acid reaction. Conjugated diene level was measured by Recknagel and Glende method. Serum uric acid, total bilirubin, serum albumin, serum ascorbic acid and lipid profile were analyzed by standard methods.ResultsTotal cholesterol, triglycerides, low-density lipoprotein cholesterol were significantly higher and high-density lipoprotein cholesterol were significantly lower in hypertensive patients when compared to normotensive healthy controls. The superoxide dismutase, glutathione peroxidase and catalase were significantly lower in hypertensive when compared with normotensive. Similar findings were observed in the levels of albumin, uric acid, bilirubin and ascorbic acid when hypertensives were compared with normotensive. The oxidative stress indicators namely malondialdehyde and conjugated diene were significantly higher and paraoxonase activity were significantly lower in hypertensive.ConclusionsOur study concludes that paraoxonase activities are bound to alter in hypertension which is caused due to interplay of several confounding factors namely oxidative stress, increased oxidized low-density lipoprotein and depletion of antioxidants. 相似文献
264.
对氧磷酶2基因311Cys/Ser多态性与2型糖尿病合并大血管病变的相关性 总被引:3,自引:0,他引:3
目的探讨对氧磷酶2基因311 Cys/Ser多态性与山东青岛地区2型糖尿病患者合并大血管病变的关系。方法通过抽提基因组DNA并应用聚合酶链反应扩增包含对氧磷酶2基因311位点的基因片段,然后应用聚合酶链反应限制片长多态性技术检测对氧磷酶2基因311 Cys/Ser多态性在2型糖尿病合并大血管病变组、单纯2型糖尿病组以及正常对照组的基因频率。结果山东青岛地区人群存在对氧磷酶2基因311 Cys/Ser多态性。2型糖尿病合并大血管病变组对氧磷酶2基因的3种基因型(CC、CS、SS)的构成比与单纯2型糖尿病组和正常对照组比较差异具有显著性(P<0.05或P<0.01),S等位基因频率较单纯2型糖尿病组和正常对照组显著增高(P<0.05或P<0.01);携带S等位基因的个体患糖尿病大血管病变的风险为非携带者的2.932倍;对氧磷酶2基因311 Cys/Ser多态性不同基因型亚组间血脂水平无明显差异。结论在山东青岛地区人群中,对氧磷酶2基因311 Cys/Ser多态性与2型糖尿病合并大血管病变具有相关性,其S等位基因可能是该地区2型糖尿病合并大血管病变的危险因素之一。 相似文献
265.
Sierksma A van der Gaag MS van Tol A James RW Hendriks HF 《Alcoholism, clinical and experimental research》2002,26(9):1430-1435
BACKGROUND: The inverse association between moderate drinking and coronary heart disease mortality is well established. This study was performed to investigate the kinetics of the alcohol-induced increases in apo A-1, HDL cholesterol, and paraoxonase (PON) activity, as well as to study whether the alcohol-induced increases in PON activity differ within different PON polymorphisms, and to investigate whether moderate alcohol consumption has similar effects on the outcome measures in postmenopausal women as in middle-aged men. METHODS: In a randomized, diet-controlled, crossover study, 10 middle-aged men and 9 postmenopausal women, all apparently healthy, nonsmoking, and moderate alcohol drinkers, consumed beer or no-alcohol beer (control) with evening dinner during two successive periods of 3 weeks. During the beer period, alcohol intake equaled 40 and 30 g/day for men and women, respectively. The total diet was supplied to the subjects and had essentially the same composition during these 6 weeks. Before each treatment was a 1-week washout period, in which the subjects were not allowed to drink alcoholic beverages. RESULTS: Moderate alcohol consumption significantly increased serum apo A-I level after 5 days (3.7%, p < 0.05); after 10 days, serum HDL cholesterol level was increased (6.8%, p < 0.001), and after 15 days serum PON activity was increased (3.7%, p < 0.05), all compared with no alcohol consumption. Gene polymorphisms did not modulate the alcohol effect on PON. CONCLUSIONS: Serum apo A-I, HDL cholesterol, and PON activity were significantly increased during 3 weeks of moderate alcohol consumption as compared with no alcohol consumption. Moreover, the results suggest that there is a sequence in induction of these parameters. After an increase in apo A-I, HDL cholesterol is increased followed by an increase in PON activity. Increased serum HDL cholesterol level and PON activity may be a mechanism of action not only in healthy middle-aged men but also in postmenopausal women, underlying the reduced coronary heart disease risk in moderate drinkers. 相似文献
266.
对氧磷酯酶-1与老年人2型糖尿病视网膜病变的关系 总被引:2,自引:0,他引:2
目的探讨血清对氧磷酯酶1(PON1)活性与老年人2型糖尿病(T2DM)并发视网膜病变(DR)的关系。方法血清PON1活性用酚乙酸酯为底物测定。血浆氧化型低密度脂蛋白(oxLDL)用ELISA法测定。结果老年单纯T2DM组PON1活性为(9608±3143)kU/L,比健康对照组显著降低〔(13028±1948)kU/L,P<001〕,T2DM并发DR组PON1活性(7453±1679)kU/L,比老年单纯T2DM组显著降低(P<001)。oxLDL浓度在老年单纯T2DM为(6996±841)μg/L,比健康对照组显著升高〔(4264±763)μg/L,P<001〕,老年人T2DM并发DR组oxLDL浓度为(8123±849)μg/L比老年单纯T2DM组显著升高(P<001)。PON1活性与oxLDL的浓度呈高度负相关(r=-084,P<001),Logistic回归分析表明PON1活性是T2DM并发DR的高度危险因素(P<001)。结论PON1活性在T2DM显著下降,且在并发T2DM患者下降更显著。PON1活性与oxLDL呈负相关。PON1活性降低是T2DM并发DR的高度危险因素。 相似文献
267.
Memduh Sahin Onur Bobusoglu Aylin Yetim Fehmi Ates 《Arab Journal Of Gastroenterology》2019,20(1):14-18
Background and study aims
The role of oxidative stress in inflammatory bowel disease is increasingly recognised as an important factor. It is assumed that reduced levels of paraoxonase-1 (PON-1) and arylesterase (ARE) may lead to increased inflammation due to increased oxidative stress. This study aimed to investigate the relationship between ARE and PON-1 levels in ulcerative colitis (UC) patients and the difference in these levels in UC patients in comparison to the control group.Patients and methods
The study population consisted of 66 (73.3%) UC patients and 24 (26.7%) healthy individuals as the control group. The UC patients and the control group were compared in terms of PON-1 and ARE levels as oxidative stress markers. The UC patients were also grouped according to Mayo UC activity scores, and the differences in their PON-1 and ARE levels were assessed.Results
The ARE values were statistically higher in the control group in comparison to the UC patients. Concentrations of PON-1 were not statistically different in the UC and control groups. The ARE value was found to be significantly lower in the UC patients with a haemoglobin level below 10?mg/dl. There was a correlation between the ARE and PON-1 values in the UC patients, but there was no difference between the ARE and PON-1 values, based on the UC patients’ Mayo disease severity scores.Conclusion
This study found that the ARE values of UC patients were lower than those of healthy subjects. The same results could not be determined for PON-1. The data suggest that the antioxidative capacity of UC patients may be reduced. 相似文献268.
郑州地区汉族人群2型糖尿病并发冠心病患者与对氧磷酯酶/芳香酯酶192位基因多态性的关系 总被引:2,自引:1,他引:2
目的探讨郑州地区汉族人群对氧磷酯酶/芳香酯酶(Paraoxonase1/ Arylesterase, PON1/ArE)192位基因多态性与2型糖尿病(DM)并发冠心病(DM-CHD)的关系.方法观察对象均为郑州地区汉族居民,其中DM组121例、DM-CHD组125例、非糖尿病急性心肌梗死(AMI)组50例、对照组127例,用聚合酶链反应技术检测其PON1/ArE 基因192位多态性,终点法测定血清PON1/ArE活性,酶法与酶联免疫法测定胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、氧修饰低密度脂蛋白(ox-LDL)等指标后,分析研究.结果①郑州地区汉族人群PON1/ArE192位Q、R基因频率,DM组为0.52、0.48,DM-CHD组为0.37、0.63,AMI组0.53、0.47,对照组分别为0.54、0.46.DM与AMI组Q、R基因频率和对照组差异无显著性意义,DM-CHD组R基因频率大于这3组.②DM和DM-CHD组PON1/ArE活性降低,降低幅度DM-CHD组接近于AMI组,大于DM组.DM与DM-CHD组内各基因型组中RR基因型患者ox-LDL、TC、TG、载脂蛋白B100等水平均高于QQ型(P<0.01),HDL-C低于QQ型患者,DM-CHD组中的RR基因型的异常改变最为明显.AMI组内各基因型的ox-LDL无明显差异.结论郑州地区汉族人群存在PON1/ArE192位基因多态性,并提示R基因是郑州地区汉族人群DM并发DM-CHD的危险因素. 相似文献
269.
目的:探讨中国人对氧磷酶-1(PON-1)基因55位、192位多态性与冠心病(CHD)发病的关系及是否影响CHD的病变程度。方法:应用多聚酶链反应限制性片段长度多态性(PCR-RFLP)方法,对经Judkins选择性冠状动脉造影方法证实的151例CHD患者和61例非CHD的对照人群进行检测,分析PON-1基因55、192位多态性,以及其与Gensini积分表示的冠状动脉病变程度的相关性。结果:CHD组55位L等位基因频率为91%,高于对照组的87%(χ2=6.66,P<0.01)。CHD组192位B等位基因频率为65%,高于对照组的29%(χ2=45.07,P<0.01),CHD患者3种基因型间冠状动脉积分存在差异,BB基因型具有更高的冠状动脉积分(H=11.631,P<0.01)。结论:PON-1基因192位多态性与CHD之间有关联;而未发现PON-1基因55位多态性与CHD有关系。PON-1基因55位L等位基因、192位B等位基因与CHD的发病有关,而且PON-1基因192位多态性影响了冠状动脉病变的程度。 相似文献
270.
血清对氧磷酶活性测定方法研究 总被引:8,自引:0,他引:8
根据对氧磷酶能水解对氧磷成为对硝基酚原理,用EDTA终止酶促反应.分光光度法测定对硝基酚(黄色化合物、在412nm处有吸收峰)的生成量,反映对氧磷酶的活性水平.结果显示酶活性在0~1600单位范围内与吸光度值呈线性,方法的变异系数在1.49%~4.27%间.加入不同量的酶,实测值与理论值的差异误差百分比分别为17.11%、11.2%和4.95%.同一样本重复测定,变异系数为10.11%~10.54%.说明检测方法用血量少、酶反应时间短,用EDTA抑制酶活性后,能在普通分光光度计上进行测定,可以普遍使用. 相似文献