@article{oai:repo.qst.go.jp:00047417,
 author = {Ishihara, Hiroshi and Tanaka, Izumi and Yakumaru, Haruko and Tanaka, Mika and Yokochi, Kazuko and Fukutsu, Kumiko and Tajima, Katsushi and Nishimura, Mayumi and Shimada, Yoshiya and Akashi, Makoto and 石原 弘 and 田中 泉 and 薬丸 晴子 and 田中 美香 and 横地 和子 and 福津 久美子 and 田嶋 克史 and 西村 まゆみ and 島田 義也 and 明石 真言},
 issue = {1},
 journal = {Journal of Radiation Research},
 month = {Nov},
 note = {Biodosimetry, the measurement of radiation damage in a biologic sample, is a reliable tool for increasing the accuracy of dose estimation. Although established chromosome analyses are suitable for estimating the absorbed dose after high-dose irradiation, biodosimetric methodology to measure damage following low-dose exposure is underdeveloped. RNA analysis of circulating blood containing radiation-sensitive cells is a candidate biodosimetry method. Here we quantified RNA from a small amount of blood isolated from mice following low-dose body irradiation (<0.5 Gy) aimed at developing biodosimetric tools for situations that are difficult to study in humans. By focusing on radiation-sensitive undifferentiated cells in the blood based on Myc RNA expression, we quantified the relative levels of RNA for DNA damage-induced (DDI) genes, such as Bax, Bbc3 and Cdkn1a. The RNA ratios of DDI genes/Myc in the blood increased in a dose-dependent manner 4 h after whole-body irradiation at doses ranging from 0.1 to 0.5 Gy (air-kerma) of X-rays, regardless of whether the mice were in an active or resting state. The RNA ratios were significantly increased after 0.014 Gy (air-kerma) of single X-ray irradiation. The RNA ratios were directly proportional to the absorbed doses in water ranging from 0.1 to 0.5 Gy, based on gamma-irradiation from 137Cs. Four hours after continuous irradiation with gamma-rays or by internal contamination with a beta-emitter, the increased RNA ratios resembled those following single irradiation. These findings indicate that the RNA status can be utilized as a biodosimetric tool to estimate low-dose radiation when focusing on undifferentiated cells in blood.},
 pages = {25--34},
 title = {Quantification of damage due to low-dose radiation exposure in mice: construction and application of a biodosimetric model using mRNA indicators in circulating white blood cells},
 volume = {57},
 year = {2015}
}