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21.
目的: 研究氟对大鼠切牙成釉细胞中TGF-β3表达的影响,探讨氟斑牙的发病机制。方法: 选择20只Wistar大鼠,随机分为Ⅰ组(蒸馏水组)和Ⅱ组(100 mg/L F- )。饲养8周后处死动物,利用H-E染色和免疫组织化学染色方法观察过量氟对大鼠成釉细胞TGF-β3表达的影响。采用SPSS 12.0软件包对数据进行统计学分析。结果: 免疫组织化学结果经图像分析显示,实验组大鼠切牙成釉细胞中TGF-β3的表达均显著低于对照组(P<0.01),对照组、加氟组的灰度值分别为85.89±7.90和116.76±8.04。结论: 过量氟可能通过抑制TGF-β3的表达而干扰上皮和间充质之间正常的信号转导,进而使釉质的分化受到影响,可能是氟牙症发生的细胞内机制之一。 相似文献
22.
Objective To investigate plasma glutathione S-transferase(GSTs) activity and GSTP1 gene Ile105Val polymorphism in Bijie City, Guizhou Province, a coal-burning fluorosis endemic area. Methods One hundred and sixty villagers from Yachi Twon using non-improved cooking stoves were selected as the non-intervened group in Bijie City, Guizhou Province where coal-burning fluorosis was prevailing; 153 villagers as the intervented group were chosen from Changchun Twon, where cooking stoves were improved; 151 villagers were served as the control group from Baiyunshan Twon, Changshun County without endemic fluorosis. The activity of GSTs was tested by colorimetric analysis with spectrophotometer. The genotype of the GSTP1 gene Ile105Val polymorphism, presenting as either homozygous wild-type (AA), or heterozygous mutation type (AG), or homozygous mutation type (GG), was detected through the PCR-RFLP procedure. Results The activity of GSTs in plasma of non-intervened group [(12.44±4.97) kU/L]was significantly lower than that of intervened group (P < 0.05), and that of intervened group[(20.78±6.20)kU/L]was significantly lower than that of control group[(24.30±6.27)kU/L, P< 0.05]. The difference of the enzyme activity of three groups were statistically significant (F = 51.71, P < 0.05), but this enzyme activity did not vary significantly in each sex of each grnup(P > 0.05). Compared intervened group [AA:67.3%(103/153), AG:29.4%(45/153),GG:3.3%(5/153)]and non-intervened group[AA:66.9%(107/160), AG:30%(48/160), GG:3.1%(5/160)]with control group[AA:74.8%(113/151), AG:25.2%(38/151), GG:0 (0/151)], the Ile105Val polymorphism site of GSTP1 gene had significant difference(χ2= 6.04,6.07, both P< 0.05), but not significant between intervened and non-intervened groups(χ2 = 0.02, P>0.05). Conclusions Fluorosis can decrease the activity of GSTs and introduce the GSTP1 gene Ile105Val polymorphism, intervention with the fluorine intake will improve the effect of fluoride on the body. 相似文献
23.
Objective To investigate plasma glutathione S-transferase(GSTs) activity and GSTP1 gene Ile105Val polymorphism in Bijie City, Guizhou Province, a coal-burning fluorosis endemic area. Methods One hundred and sixty villagers from Yachi Twon using non-improved cooking stoves were selected as the non-intervened group in Bijie City, Guizhou Province where coal-burning fluorosis was prevailing; 153 villagers as the intervented group were chosen from Changchun Twon, where cooking stoves were improved; 151 villagers were served as the control group from Baiyunshan Twon, Changshun County without endemic fluorosis. The activity of GSTs was tested by colorimetric analysis with spectrophotometer. The genotype of the GSTP1 gene Ile105Val polymorphism, presenting as either homozygous wild-type (AA), or heterozygous mutation type (AG), or homozygous mutation type (GG), was detected through the PCR-RFLP procedure. Results The activity of GSTs in plasma of non-intervened group [(12.44±4.97) kU/L]was significantly lower than that of intervened group (P < 0.05), and that of intervened group[(20.78±6.20)kU/L]was significantly lower than that of control group[(24.30±6.27)kU/L, P< 0.05]. The difference of the enzyme activity of three groups were statistically significant (F = 51.71, P < 0.05), but this enzyme activity did not vary significantly in each sex of each grnup(P > 0.05). Compared intervened group [AA:67.3%(103/153), AG:29.4%(45/153),GG:3.3%(5/153)]and non-intervened group[AA:66.9%(107/160), AG:30%(48/160), GG:3.1%(5/160)]with control group[AA:74.8%(113/151), AG:25.2%(38/151), GG:0 (0/151)], the Ile105Val polymorphism site of GSTP1 gene had significant difference(χ2= 6.04,6.07, both P< 0.05), but not significant between intervened and non-intervened groups(χ2 = 0.02, P>0.05). Conclusions Fluorosis can decrease the activity of GSTs and introduce the GSTP1 gene Ile105Val polymorphism, intervention with the fluorine intake will improve the effect of fluoride on the body. 相似文献
24.
Ranjith W. Dharmaratne 《Environmental health and preventive medicine》2015,20(4):237-242
A significant number of people in the North Central Province of Sri Lanka suffer from chronic kidney diseases (CKD), and the author revisits existing literature related to CKD to find its causative factor. There is a direct connection between high fluoride levels in drinking water and kidney disease, and there are unhealthy levels of fluoride in the groundwater in Sri Lanka’s CKD-affected areas. Based on the following observations, the author believes with confidence that excess fluoride in drinking water and in the locally grown food in the affected areas are the culprits of CKD in Sri Lanka.
- Fluoride excretion rate is considerably lower in children than adults, leading to renal damage of children living in areas with high fluoride.
- Adults who had renal damage due to fluoride in childhood are vulnerable to CKD with continued consumption of water from the same source.
- Patients with chronic renal insufficiency are at an increased risk of chronic fluoride toxicity.
- High content of fluoride in groundwater paves the way to excess fluoride in local food crops, consequently adding more fluoride to the systems of the consumers.
- People who work outdoors for prolonged periods consume excess water and tea, and are subjected to additional doses of fluoride in their system.
- In the mid-1980s, the increase in water table levels of the affected areas due to new irrigation projects paved the way to adding more fluorides to their system through drinking water and locally grown foods.
25.
目的 了解全国改水降氟措施防治饮水型地方性氟中毒的效果,探索控制饮水型氟中毒改水干预措施效果的综合评价方法。方法 制定纳入标准、剔除标准,制定检索策略;通过检索,共查找相关文献450篇,其中符合Meta分析要求的有效文献54篇。采用Cochrane协作网提供的Revman4.2.3统计软件对入选文献进行Meta分析。结果 改水11~20年,儿童氟斑牙患病率从69.3%降到23.8%,成人氟骨症患病率下降了4.9%,儿童尿氟由5.31mg/L降到1.50mg/L。改水21~31年,儿童氟斑牙患病率从78.6%降到23.9%,成人氟骨症患病率下降19.2%。平均改水13年,水含氟量由改水前的4.85mg/L降到0.60mg/L。改水后经济效益明显增加,血生化指标明显降低。结论改水降氟是防治饮水型氟中毒的有效措施,只要饮水含氟量降到允许标准以下,儿童氟斑牙患病率、成人氟骨症患病率和儿童尿含氟量都会明显降低。经济效益的增加间接反映了改水降氟的效果。Meta分析为从整体水平揭示全国改水降氟预防饮水型地方性氟中毒的效果提供了新的研究方法和手段,将对饮水型氟中毒防控干预措施效果综合评价研究起到积极的推动作用。 相似文献
26.
目的 了解山东省黄河流域内地方性氟中毒流行现状,为制订防治策略提供科学依据.方法 在山东省选择9个病区县进行了流行病学调查,居民饮用水含氟量测定采用氟离子选择电极法,8~12儿童氟斑牙诊断采用Dean法.结果 水氟均值≤1.00 mg/L的村占34.41%(606/1761);>1.00 mg/L的村占65.59%(1155/1761);水氟最大值为11.33 mg/L.水氟均值≤1.00 mg/L的改水降氟工程占72.65%(449/618):>1.00mg/L的改水降氟工程占27.35%(169/618);水氟最大值为5.85 mg/L.8~12岁儿童氟斑牙总患病率为45.03%(25 579/56 804),氟斑牙指数为0.80.结论 山东省黄河流域内50.00%以上的村庄水氟超过国家标准(≤1.00 mg/L),地方性氟中毒的流行尚未得到有效控制,须尽快落实防治措施. 相似文献
27.
A. Parsian R. D. Todd C. R. Cloninger P. L. Hoffman L. Ovchinnikova H. Ikeda B. Tabakoff 《Alcoholism, clinical and experimental research》1996,20(4):745-751
Adenylyl cyclase (AC) activity was measured in membrane preparations of platelets from control and alcoholic subjects. The sample consisted of 51 alcoholics who were categorized as type I or type II using the criteria of Gilligan et al. ( Genet. Epidemiol. 4:395–414, 1987) and 54 normal controls. Alcoholic males exhibited significantly lower values than controls in basal and fluoride-stimulated platelet AC activity. When male alcoholics were segregated into type I and type II categories, the platelet AC activity did not differ between subtypes, and both subtypes had AC activity that was below control values. Western blot analysis of the quantity of Gs α and Gi α proteins in a subset of male controls and alcoholic subjects demonstrated no significant relationship between quantity of G proteins and AC activity. The results confirm lower platelet AC activity in male alcoholics, compared with controls. Given the lack of quantitative relations between Gs α and Gi α proteins and AC activity, the results support the contention that individual differences in platelet AC activity in the alcoholic subjects may reflect quantitative or qualitative differences in the AC catalytic units. 相似文献
28.
29.
氟对大鼠子代脑单胺类神经介质的影响 总被引:5,自引:1,他引:5
Wistar大鼠自查到阴栓起,分别自由饮用0.6mg/L(对照组)、1mg/L、5mg/L、25mg/L含氟水,其仔鼠饮用同浓度含氟水至90d,观察胚胎期及生长发育期接触氟对仔鼠大脑功能的影响。采用高压液相色谱-电化学法对大脑单胺类神经介质测定结果显示,除多巴胺的代谢产物之一-3,4-二羟乙酸(DOPAC)的含量在高剂量组显著降低外,去甲肾上腺素(NE)、多巴胺(DA)、高香草酸(HVA)、5-羟色胺(5-HT)和5-羟吲哚乙酸(5-HIAA)的含量与对照组比较均无显著差异,表明氟可抑制DA的代谢转化,对单胺氧化酶(MAO)的活性有一定的抑制作用。提示氟对仔鼠的大脑功能有一定的不良影响。 相似文献
30.
目的探讨健康教育处方在控制燃煤污染型地方性氟中毒(简称地氟病)中的效果和作用。方法采取卫生行政和疾病控制部门协调、对项目乡村干部和医务人员进行相关知识培训、基线调查、确定针对性的健康教育处方内容,并在乡村卫生院(室)实施,实施后随机抽样追踪调查与评估。结果试点研究期间共计开出有效健康教育处方1882人份,作为宣传单自由阅取约4000人份。项目实施后家庭户主知晓率提高近40%,学生知晓率提高约25%,健康教育处方接受者总体知晓率为63.40%,较基线(8.91%)显著提高。干预后炉灶密闭使用率和烟囱出屋率均显著提高。项目乡村居民已全部不用敞煤火干燥玉米,辣椒煤火干燥率显著减少,密闭保存率显著提高。78%的地氟病防治卫生知识知晓人群已向他人讲解传播,47%的人已采取降氟措施。结论地氟病健康教育处方试点工作在促进病区人群自我保健与防护意识、行为改变和形成方面取得初步成效,为深化贵州省地氟病健康教育与健康促进干预研究,探讨地氟病健康教育与健康促进的可持续性发展模式,以及为在全省推广运用提供了基础数据和科学依据。 相似文献