权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

MECHANISMS IN SHOULDERED SURVIVAL CURVES

肩负生存曲线的机制

基本信息

批准号：
3482051
负责人：
JOHN R WARD
金额：
$ 29.01万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
1991
资助国家：
美国
起止时间：
1991-01-01 至 1993-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/3482051
关键词：
DNA damage DNA repair HeLa cells cell cycle cell death cell transformation hamsters human subject ionizing radiation radiation carcinogenesis radiation dosage radiation hazard radiation protection radiation sensitivity

项目摘要

Repair of ionizing radiation induced damage in mammalian cell DNA is crucial to cell survival. Shoulders on mammalian cell radiation survival curves can be explained by invoking saturation of a repair process at higher doses. To probe this hypothesis, assays of damage are required which can be used at low radiation doses (within the shoulder) as well as high radiation doses. Such assays are proposed here which are effective down to 10 rads, these will be used to test for saturation of repair, measuring rates of repair of DNA single strand breaks, "double strand breaks", and base damage as a function of radiation dose. To probe the significance of these three types of lesions in causing cell death or transformation, attempts will be made to inhibit the repair process and test the result of this inhibition on cell survival or transformation. Also procedures which have been shown to affect cell survival will be probed as to their effects on repair. It is hoped that the information gained from these studies of DNA damage and repair at low doses will be useful in (a) determining the cause of mammalian shouldered survival curves and (b) determining the DNA lesions causing cell death and transformation so that, with the knowledge of cell repair capacity, the hazards of low dose radiation can be extrapolated.

电离辐射损伤哺乳动物细胞DNA的修复对细胞存活至关重要。哺乳动物细胞辐射存活的肩膀曲线可以通过调用修复过程的饱和度来解释，更高剂量为了探究这一假设，需要对损伤进行分析其可以在低辐射剂量（在肩部内）下使用，高辐射剂量。本文提出了有效的此类测定法低至10拉德，这些将用于测试修复的饱和度，测量DNA单链断裂、“双链”断裂和“双链”断裂的修复率断裂”，以及作为辐射剂量函数的基底损伤。探测这三种类型的病变在引起细胞死亡或转化，将试图抑制修复过程，测试这种抑制对细胞存活或转化的结果。此外，已显示影响细胞存活的程序将被研究它们对修复的影响。希望这些信息从这些低剂量DNA损伤和修复的研究中获得的信息将是用于（a）确定哺乳动物肩状存活曲线的原因和（B）确定引起细胞死亡和转化的DNA损伤这样，随着细胞修复能力的知识，低的危害，辐射剂量可以外推。