HG METABOLIZING BACTERIA IN SUBJECTS WITH DENTAL AMALGAM

汞合金在牙科汞合金受试者中代谢细菌

• 批准号: 3425543
• 负责人: Anne O'Neill Summers
• 金额: $ 2.2万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-07-01 至 1991-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3425543
• 关键词: Bacillaceae; Enterobacteriaceae; Staphylococcus; bacteria; dental amalgam; enteric bacteria; excretion; human tissue; mercury; mercury poisoning; microorganism metabolism

Bacteria resistant to and capable of biochemically transforming both inorganic and organic mercury compounds are widely found in many facultative, enbacterial genera including the enterobacteriaceae, staphylococci, streptococci, and bacillaceae (Summers, 1986). While industrial contamination can explain the occurrence of such genetic loci in water and soil populations (Barkay and Olson, 1986; Barkay, 1987; Nishimura and Kamahai, 1983; Trevors, 1986; Summers, et al., 1978) their frequent occurrence in the fecal flora of humans (Marshall et al, 1981; Gilbert and Summers, 1988) is harder to understand. It has been known for some time that Hg is released from dental amalgams and that there is considerable variation in the ability of humans to excrete this Hg in urine (Clarkson et al, 1988). Very recently, Hahn, et al. (1989) and Vimy et al (in press) have demonstrated that a substantial burden of Hg in oral and gastrointestinal tissues can result from dental amalgam Thus, the Hg in such restorations may select for resistant bacteria among the normal flora of either the mouth or bowel. Since these bacteria chemically transform Hg compounds, they could have a large influence on the bioavailability of Hg released from dental amalgam. Dr. Fritz Lorscheider and his colleagues at the University of Calgary have assessed the specific organ burden arising from dental amalgam restorations in sheep (Hahn et al, 1989) and plan similar studies in a primate model as well as a survey of selected human subjects. I propose, in collaboration with Dr. Lorscheider, to assess the incidence of Hg resistance in the oral and fecal microbial flora of his animal and human subjects and to correlate this phenomenon with amalgam mass, body burden of Hg, and excretion rate of Hg (as measured by Lorscheiders group). If we find that the presence of a highly resistant microbial flora correlates with reduced body burden or enhanced excretion of Hg, future studies could consider experimental amendment of the flora with naturally occurring Hg resistance plasmids to reduce body accumulation of this highly toxic and mutagenic metal. Alternatively, if increased Hg resistance in the flora enhances body burden, these micro-organisms constitute an additional risk-factor for the use of dental amalgam.

细菌抵抗并能够生化转化两者 无机和有机汞化合物广泛存在于 兼性的，细菌属，包括肠杆菌科， 葡萄球菌、链球菌和杆菌科（Summers，1986）。而 工业污染可以解释这些遗传位点的发生， 水和土壤种群（Barkay和Olson，1986; Barkay，1987; Nishimura 和Kamahai，1983; Trevors，1986; Summers等人，1978年：频繁 在人的粪便植物群中出现（马歇尔等人，1981;吉尔伯特和 1988年，他更难理解。一段时间以来， 汞从牙科汞合金中释放出来， 人类通过尿液排泄汞的能力存在差异（克拉克森等人 等人，1988）。最近，Hahn等人（1989）和维米等人（出版中） 已经证明，口腔和口腔中的汞含量很高， 因此，汞合金中的汞含量可能会导致胃肠道组织中的汞含量增加。 这种分离可以在正常的植物群中选择抗性细菌 口腔或肠道的损伤由于这些细菌通过化学方式转化汞 化合物，它们可能对汞的生物利用度有很大的影响 从牙科汞合金中释放出来 博士卡尔加里大学的弗里茨·洛谢德和他的同事们 评估了牙科汞合金充填引起的特定器官负担 在绵羊中（Hahn等，1989），并计划在灵长类动物模型中进行类似研究， 以及对选定的人类受试者的调查。我提议， 与Lorscheider博士一起评估口腔中汞抵抗的发生率 和粪便微生物植物群， 这种现象与汞合金质量、汞的体内负荷和汞的排泄率有关。 汞（由Lorscheiders集团测量）。如果我们发现 高度耐药的微生物植物群与降低的身体负担或 增加汞的排泄，未来的研究可以考虑实验性的 用天然存在的抗汞质粒修正植物群， 减少这种剧毒和致突变金属的体内积累。 或者，如果植物群中抗汞能力的提高， 这些微生物构成了额外的风险因素， 使用牙科汞合金。