@article{oai:repo.qst.go.jp:00043469,
 author = {Kawata, Tetsuya and Durante, Marco and Furusawa, Yoshiya and George, Kerry and Ito, Hisao and Wu, Honglu and A, Cucinotta Francesca and 川田 哲也 and 古澤 佳也 and ジョージ ケリー and 伊東 久夫 and ウー ホングル and クシノッタ フランク},
 issue = {5},
 journal = {Radiation Research},
 month = {Nov},
 note = {We reported previously that exposure of normal human fibroblasts in G2 phase of the cell cycle to high-LET radiation produces a much higher frequency of isochromatid breaks than exposure to gamma rays. We concluded that an increase in the production of isochromatid breaks is a signature of initial high-LET radiation-induced G2-phase damage. In this paper, we report the repair kinetics of isochromatid breaks induced by high-LET radiation in normal G2-phase human fibroblasts. Exponentially growing human fibroblasts (AG1522) were irradiated with gamma rays or energetic carbon (290 MeV/nucleon), silicon (490 MeV/nucleon), or iron (200 MeV/nucleon) ions. Prematurely condensed chromosomes were induced by calyculin A after different postirradiation incubation times ranging from 0 to 600 min. Chromosomes were stained with Giemsa, and aberrations were scored in cells at G2 phase. G2-phase fragments, the result of the induction of isochromatid breaks, decreased quickly with incubation time. The curve for the kinetics of the rejoining of chromatid-type breaks showed a slight upward curvature with time after exposure to 440 keV/microm iron particles, probably due to isochromatid-isochromatid break rejoining. The formation of chromatid exchanges after exposure to high-LET radiation therefore appears to be underestimated, because isochromatid-isochromatid exchanges cannot be detected. Increased induction of isochromatid breaks and rejoining of isochromatid breaks affect the overall kinetics of chromatid-type break rejoining after exposure to high-LET radiation.},
 pages = {598--602},
 title = {Rejoining of isochromatid breaks induced by heavy ions in G2-phase normal human fibroblasts.},
 volume = {156},
 year = {2001}
}