@article{oai:repo.qst.go.jp:00046855,
 author = {Ding, Nan and Pei, Hailong and He, Jinpeng and Furusawa, Yoshiya and Hirayama, Ryoichi and Liu, Cuihua and Matsumoto, Yoshitaka and Li, He and Hu, Wentao and Li, Yinghui and Wang, Jufang and Wang, Tieshan and Zhou, Guangming and 古澤 佳也 and 平山 亮一 and 劉 翠華 and 松本 孔貴 and 周 光明},
 issue = {7},
 journal = {Advances in Space Research},
 month = {Nov},
 note = {High charge and energy (HZE) particles are severe risk to manned long-term outer space exploration. Studies on the biological effects of space HZE particles and the underlying mechanisms are essential to the accurate risk assessment and the development of efficient countermeasure. Since majority of the cells in human body stay quiescent (G0 phase), in this study, we established G0 cell and G1 cell
models by releasing human normal embryonic lung fibroblast cells from contact inhibition and studied the radiation toxicity of various kinds of HZE particles. Results showed that all of the particles were dose-dependently lethal and G0 cells were more radio resistant than G1 cells. We also found that 53BP1 foci were induced in a LET- and fluence-dependent manner and fewer foci were induced in G0 cells than G1 cells, however, the decrease of foci in 24 h after irradiation was highly relevant to the type of particles. These results imply that even though health risk of space radiation is probably overestimated by the data obtained with exponentially growing cells, whose radio sensitivity is similar to G1 cells, the risk of space HZE particles is un-ignorable and accurate assessment and mechanistic studies should be deepened. The diverse abilities of G0 cells and G1 cells in repairing DNA damages induced by HZE particles emphasize the importance
in studying the impact of HZE particles on DNA damage repair pathways.},
 pages = {1314--1319},
 title = {Simulated studies on the biological effects of space radiation on quiescent human fibroblasts},
 volume = {52},
 year = {2013}
}