title: Effect of secondary radiation produced by 70 GeV protons on DNA of mammalian cells.
abstract: It is shown that the RBE of the 70 GeV proton secondary radiation for the induction of single-strand break is 1.6-7.6 in Chinese hamster fibroblasts and 1.04-3.8 in limphoid cells and for the lethality of Chinese hamster cells 1.14-1.7. The RBE value increases with decreasing dose of the secondary radiation. On post-irradiation incubation of mammalian cells at 37 degrees C, single-strand breaks induced by the secondary radiation are repaired with the sane time course as those induced by gamma-rays. In our earlier works we have made an attempt to estimate the biological efficiency of radiation generated by the 70 GeV protons on bacteria, phage T4 and Vicia faba beans. The obtained values of the relative biological efficiency (RBE) of this radiation varied between 1.4 and 5.5, depending on the object, criterion of estimation, times of registration and other experimental conditions. The aim of the present work is to estimate the biological efficiency of synchrotron radiation by its effect on mammalian cells.
authors.affiliation: Institute of Biological Physics, USSR Academy of Sciences, Pushino.
authors.forename: G A
authors.initials: GA
authors.lastname: Leont'eva
authors.forename: B S
authors.initials: BS
authors.lastname: Fomenko
authors.forename: A V
authors.initials: AV
authors.lastname: Antipov
mesh_terms: D000818:Animals; D002460:Cell Line; D002468:Cell Physiological Phenomena / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured / Q000528:radiation effects*; D006224:Cricetinae; D004247:DNA / Q000528:radiation effects*; D004249:DNA Damage; D004260:DNA Repair; D004307:Dose-Response Relationship, Radiation; D005347:Fibroblasts / Q000528:radiation effects; D005720:Gamma Rays; D008214:Lymphocytes / Q000528:radiation effects; D011522:Protons; D012062:Relative Biological Effectiveness; D017356:Synchrotrons; D014407:Tumor Cells, Cultured
chemical_list: D011522:Protons; D004247:DNA