NEUTRON ENERGY: DOSE PROTRACTION EFFECT ON TRANSFORMATI

中子能量：对转变的剂量延长效应

• 批准号: 3184373
• 负责人: COLIN K HILL
• 金额: $ 18.45万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-11-01 至 1988-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3184373
• 关键词: cancer risk; embryo /fetus tissue /cell culture; ionizing radiation; neutron radiation; particle beam; radiation carcinogenesis; radiation dosage; radiation sensitivity; relative biological effectiveness

Neoplastic transformation of individual cells is believed to be the underlying cause of tumorigenesis. Ionizing radiation is a potent inducer of neoplastic transformation in vitro. Recent studies have shown that both the rate of delivery and the quality of the radiation can markedly affect the observed transformation frequency. Studies with fission-spectrum neutrons at the Janus reactor at the Argonne National Laboratory have indicated that induction of transformation is greatly enhanced when low doses are delivered protracted over time. The implications of these observations could be very important for those occupationally or medicinally exposed. Using rodent cells that have been adapted for the assay of neoplastic transformation in vitro, we propose to determine the following: (1) the dose dependency for neoplastic transformation for a variety of average neutron energies ranging from 0.86 to 25 MeV mean energy; (2) the effect of dose protraction (i.e., low-dose-rate irradiation or multifractionation of high-dose-rate exposures) as a function of average neutron energy of fast neutron beams; (3) the mechanism of the enhanced induction of transformation as can be studied through the use of promoters and antipromoters (including radioprotectors); and (4) the possible basis for the role of antipromoters as a prophylaxis for civilian personnel, medical patients, and military personnel who may be exposed to protracted exposures of neutrons from sources that have a variety of mean energies.

单个细胞的肿瘤转化被认为是肿瘤发生的原因。 肿瘤发生的根本原因。 电离辐射是一种强有力的诱导剂 体外肿瘤转化。 最近的研究表明， 放射线的输送速度和质量会显著影响 观察到的转化频率。 裂变谱研究 阿贡国家实验室的Janus反应堆中的中子 表明，当低浓度时，转化诱导大大增强， 剂量随时间延长递送。 这些影响 观察可能对那些职业或 药物暴露。 使用已经适应于测定肿瘤的啮齿动物细胞， 在体外转化，我们建议确定：（1） 各种平均值的肿瘤转化的剂量依赖性 中子能量范围为0.86至25 MeV平均能量;（2） 剂量延长（即，低剂量率辐射或多分割 高剂量率照射）作为快中子平均能量的函数 中子束的增强感应机制; 可以通过使用启动子研究转化， 抗促进剂（包括辐射保护剂）;和（4）可能的基础 反促进剂作为文职人员、医疗人员、 患者和可能长期暴露的军事人员 来自不同平均能量源的中子。