@misc{oai:repo.qst.go.jp:00059904,
 author = {Ban, Sadayuki and Sudou, Hitomi and Saegusa, Kumiko and Sagara, Masashi and Imai, Takashi and Oda, Kenji and Kuramoto, Ken and Tanaka, Hideo and Kimura, Akiro and 伴 貞幸 and 須藤 仁美 and 三枝 公美子 and 相良 雅史 and 今井 高志 and 小田 健司 and 蔵本 憲 and 田中 英夫 and 木村 昭郎},
 month = {Aug},
 note = {A preliminary epidemiological study demonstrated that myelodysplastic syndrome (MDS) has an excess relative risk per sievert of 13 in atomic bomb survivors in Hiroshima. MDS is the only other radiogenic blood disease apart from leukemia. Clinically, MDS involves dysplastic hematopoiesis and an increased risk of leukemic transformation. Because it is uncertain whether MDS pathogenesis affects lymphoid progenitor cells as well as myeloid progenitor cells, we investigated the karyotypes of bone marrow cells and the micronucleus (MN) frequency in peripheral T lymphocytes of twenty- three atomic bomb survivors with MDS and five normal individuals. Aneuploidy was observed in 10 of 23 patients. Chromosome aberrations were observed in 3 of 12 patients with mild symptoms, and six of 11 patients of severe symptoms. The spontaneous- and X-ray-induced-MN frequencies were significantly higher in MDS patients than in normal individuals. Interestingly, radiation sensitivity increased along with the severity of MDS clinical subtypes. Because many of the patients in this study had not been exposed to chemo- or radiation- therapy, their unusual radiosensitivity may be related to their chromosomal or genomic instability. Immortalized lymphoid cell lines were established from B-lymphocytes infected with Epstein-Barr virus in vitro. The abrogation of radiation-induced-G2/M arrest was observed in the MDS-B lymphoid cell lines, but not in the normal B lymphoid cell lines. Our data suggest that the control of chromosomal stability is impaired in pluripotent stem cells of MDS patients, and that the abrogated G2/M arrest may be involved in the pathophysiology of disease progression and the high radiation sensitivity of patients., The 12th International Congress of Radiation Research(ICRR)},
 title = {Chromosomal instability and the abrogated G2/M arrest in X-irradiated myelodysplastic syndrome cells},
 year = {2003}
}