TREATMENT OUTCOMES IN MODERATELY LEAD TOXIC CHILDREN

拟议研究的长期目标是改善有害的 儿童吸收适量铅（Pb）的影响。 为了 为此，我们希望评估生物化学和功能后果， 在一个全面的范围内， 临床研究计划的重点是螯合治疗的效果。 由于我们的多学科方法，我们关注 铅负荷与三种结局的关系。 身体 铅负荷的测量方法有三种：1）血铅浓度， 2）CaNa 2 EDTA刺激期间的尿铅排泄 测试，可移动的铅存储的指数;和3）X射线荧光 骨铅测量，直接测量骨铅积累 随着时间 结果的措施，即那些受铅负荷， 包括1）生化异常-红细胞原卟啉水平 (EP)全血和1，25-二羟维生素D（1，25-（OH）2D） 血清中的浓度; 2）中枢神经系统功能障碍， 听觉和体感诱发电位; 3）行为缺陷 根据全球的智力指标和具体的指标， 注意力和反应时间。 预处理/后处理设计将使我们能够 描述治疗随时间推移对多种结局的影响， 推断中度铅中毒对儿童的影响 脑功能和行为，并探讨不同的方式，铅可能 发挥其影响。

The long-term goal of the proposed research is to ameliorate the harmful effects in children of absorbing moderate amounts of lead (Pb). In order to do this, we wish to assess the biochemical and functional consequences of moderate body burdens of Pb in young children within a comprehensive clinical research program focused on the effects of chelation treatment. Because of our multidisciplinary approach, we are concerned with the relationships between body burden of Pb and three type of outcomes. Body Pb burden is measured in three ways: 1) blood Pb concentrations, an index of recent exposure; 2) urinary Pb excretion during CaNa2EDTA provocative testing, an index of mobilizable Pb stores; and 3) x-ray fluorescence measurement of bone Pb, direct measurement of bone Pb that has accumulated over time. The outcome measures, that is, those affected by lead burden, include 1) biochemical abnormalities -- erythrocyte protoporphyrin levels (EP) in whole blood and 1,25-dihydroxyvitamin D (1,25-(OH)2D) concentrations in serum; 2) central nervous system dysfunction as indexed by auditory and somatosensory evoked potentials; and 3) behavioral deficits as indexed by global measures of intelligence as well as specific measures of attention and reaction time. A pre-/post-treatment design will allow us to describe the effects of treatment on multiple outcomes over time, to make inferences about the effects of moderate Pb toxicity on children's brain function and behavior, and to explore different means by which Pb may exert its effects.