PRENATAL BLOOD AND BONE LEAD EFECTS ON INFANT OCULOMOTOR FUNCTION

该项目将调查孕前母体骨铅的作用 和产前母体血铅对婴儿眼跳和 流畅的追逐眼球运动。该项目将研究一种传统的 服务不足，主要是拉美裔和非裔美国人的市中心人口 在洛杉矶中南部的金/德鲁医疗中心。目标是 人口的血铅水平高于全国平均水平。这个 一项研究试图确定母体血铅在特定时期是否 怀孕，代表胎儿发育的不同阶段， 与母血相比，母血与眼球运动功能改变的相关性更高 其他孕期的铅含量。它将决定是否会产生 产前铅暴露可测量从六个月到两年 年龄。它还将研究出生后血铅水平是否可以预测变化 眼球运动功能。这项研究将确定母亲的骨铅 在有或没有影响的情况下导致眼球运动发育改变 孕妇在怀孕期间的血铅水平。它将决定哪一个 两个铅暴露指数中的一个能更好地预测发育缺陷。 母亲将在一次怀孕结束时被招募，并一直跟踪到 他们下次怀孕时要获得孕前的骨铅。母血 铅将在口译期间和怀孕期间进行测量 而母亲的骨铅只有在解释期间才会被测量 时间间隔。婴儿从出生起每6个月测量一次血铅。 用原子吸收光谱法测定血铅 石墨炉。用K波段X射线荧光法测定骨铅 配备109Cd源、快速光谱放大器和高级光谱 分析算法。将用红外线测量眼球运动功能 具有自动头部跟踪功能的瞳孔-角膜反射电视扫描仪。 将测量潜伏期和准确性的扫视参数，以及 水平阶跃跟踪速度增益的平滑参数 移位视觉目标。将使用多元回归技术来 控制混淆和控制变量，如营养、疾病 和伤害，以测试铅措施对 眼球运动功能。眼球运动功能是一种重要的行为，它允许 使婴儿适应获取视觉信息的能力。此函数 是儿童充分发展的首要条件。测试是文化方面的- 无铅和验证铅对它们的影响将允许它们得到更广泛的使用 在任何人口中。骨铅测量可能会补充传统的 血铅测量在确定监管机构接触限值中的作用 目的。

The project will investigate the role of prepregnancy maternal bone lead and prenatal maternal blood lead upon alterations in infant saccadic and smooth pursuit eye movements. The project will study a traditionally underserved, primarily Latino and African-American inner city population in South Central Los Angeles at the King/Drew Medical Center. The target population has higher blood lead levels than the national average. The study seeks to determine if maternal blood lead during specific periods of pregnancy, representing different phases of fetal development, are more highly correlated with altered oculomotor function than maternal blood lead at other periods of pregnancy. It will determine if the effects of prenatal lead exposure can be measured from six months to two years of age. It will also see if postnatal blood lead levels predict altered oculomotor function. The study will determine if maternal bone lead contributes to altered oculomotor development with or without influence upon maternal blood lead level during pregnancy. It will determine which of the two lead exposure indices better predict developmental deficit. Mothers will be recruited near the end of one pregnancy and followed until their next pregnancy to obtain a prepregnancy bone lead. Maternal blood lead will be measured in the interpregnancy interval and during pregnancy while maternal bone lead will be measured only during the interpregnancy interval. Infant blood lead will be measured every 6 months from birth. Blood lead will be measured by atomic absorption spectrometry with graphite furnace. Bone lead will be measured by K-band X-ray fluorescence with 109Cd source, fast spectroscopy amplifier and advanced spectral analysis algorithms. Oculomotor function will be measured by infrared pupil-corneal reflection television scanner with automatic head tracking. Saccade parameters of latency and accuracy will be measured, along with smooth pursuit parameters of velocity gain using step-ramp horizontally displaced visual targets. Multiple regression techniques will be used to control for confounding and control variables, such as nutrition, illness and injury, in order to test the effects of the lead measures upon oculomotor function. Oculomotor function is a vital behavior that allows the infant to orient itself to acquire visual information. This function is primary to adequate development of the child. The tests are culture- free and validation of lead effect upon them will permit their wider use in any population. Bone lead measurements may supplement traditional blood lead measurements in determining exposure limits for regulatory purposes.