Effects of neutrons on human sperm chromosomes

本文<60><252>用我们研制的金黄地鼠卵母细胞体外受精系统研究了~（40）Co γ射线和~（40）Cf中子对人精子染色体的影响，以估算中子的相对生物学效应（RBE）。根据两个指数，经常预算开支估计为1.7和2.0，即，染色体异常精子的频率和每个精子染色体结构畸变的数量。这些数值明显低于人淋巴细胞（10-80）、小鼠精原细胞（20-25）和早期胚胎（4.7-7.4）的数值。在使用冻融卵母细胞和新鲜卵母细胞的两种试验系统之间，辐射诱导的精子染色体畸变频率无显著差异，表明卵母细胞的冷冻不影响畸变频率。冻存仓鼠o ...更多信息 本研究还尝试了冷冻保存人精子的方法。用简化的方法冷冻照射后的精液，冷冻后不同时间解冻，并进行染色体分析。在任何时间段均未发现染色体畸变增加，表明冷冻保存对辐射诱导的精子DNA损伤无影响。这种方法是有用的重复使用的细分冷冻样品和运输的样品为以后的cytogeneticuse.To获得背景数据的遗传风险评估的辐射，人类精子染色体畸变的自发发病率估计精液样本从51个健康的日本男子。染色体异常精子的频率为15.5（±）SY。[)4.2%，平均。供者年龄与畸变率无相关性。吸烟的习惯也与此无关。少

Effects of ^<60>Co gamma-rays and ^<252>Cf neutrons on human sperm chromosomes were studies using our interspecific in vitro fertilization system with golden hamster oocytes to estimate relative biological effectiveness (RBE) of neutrons. The RBEs were estimated to be 1.7 and 2.0 with two indices, i.e., the frequency of chromosomally abnormal spermatozoa and the number of structural chromosome aberrations per spermatozoon. These values were considerably lower than those obtained by previous investigators in human lymphocytes (10-80), mouse spermatogonia (20-25) and early embryos (4.7-7.4).An attempt was made to apply cryopreserved golden hamster oocytes to cytogenetic study of irradiated human spermatozo. There was no significant difference in the frequency of radiation-induced sperm chromosome aberrations between the two assay systems using frozen-thawed oocytes and fresh oocytes, indicating that freezing of the oocytes does not affect the aberration frequency. Cryopreserved hamster o … More ocytes are useful to carry out spermchromosome study more conveniently and efficiently.We also tried to use cryopreserved human spermatozoa in this study. The irradiated semen samples were frozen with a simplified method, thawed at different intervals after cryopreservation, and processed for chromosome analysis. No increase of chromosome aberrations was found at any intervals, indicating that cryopreservation has no effects on radiation-induced DNA damage in spermatozoa. This method is useful for repeated use of subdivided frozen samples and transportation of sample for later cytogenetical use.To obtain background data for genetic risk assessment of radiation, spontaneous incidence of chromosome aberrations in human spermatozoa was estimated with semen samples from 51 healthy Japanese men. The frequency of chromosmally abnormal spermatozoa was 15.5(]SY.+-。[)4.2% on an average. There was no correlation between aberration frequency and age of donors. The habit of cigarette smoking was also unrelated. Less