title: Detection of DNA damages and repair in human culture cells with simulated space radiation.
abstract: DNA damages and its repair of cultured WI38 human fibroblast cells and T98G human glioblastoma cells were studied by exposing to carbon ion beams of HIMAC accelerator. The exposed cells were incubated at 37 degrees C for appropriate intervals and the damages were analyzed by alkaline comet assay and quantitative RT-PCR with p53 mRNA. Highly inhomogeneous DNA damages were observed among the electrophoretic cell images of the comet assay. The degree of the damages was analyzed semi-quantitatively by using the Comet Index. The damaged fraction of WI38 cells was 85% immediately after 4 Gy (100keV/micrometer) irradiation and decreased to 50% after 120 min. incubation indicating a repair of cell DNA. Time dependent p53 gene expression as also analyzed by the quantitative RT-PCR method.
authors.affiliation: National Space Development Agency of Japan, Tsukuba.
authors.forename: S
authors.initials: S
authors.lastname: Nagaoka
authors.forename: T
authors.initials: T
authors.lastname: Nakano
authors.forename: S
authors.initials: S
authors.lastname: Endo
authors.forename: T
authors.initials: T
authors.lastname: Onizuka
authors.forename: Y
authors.initials: Y
authors.lastname: Kagawa
authors.forename: K
authors.initials: K
authors.lastname: Fujitaka
authors.forename: K
authors.initials: K
authors.lastname: Ohnishi
authors.forename: A
authors.initials: A
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Ohnishi
mesh_terms: D002244:Carbon; D002478:Cells, Cultured; D020552:Comet Assay; D004247:DNA; D004249:DNA Damage; D004260:DNA Repair; D004307:Dose-Response Relationship, Radiation; D005347:Fibroblasts / Q000528:radiation effects; D005786:Gene Expression Regulation / Q000528:radiation effects; D016158:Genes, p53 / Q000528:radiation effects; D020450:Heavy Ions; D006801:Humans; D010315:Particle Accelerators; D016133:Polymerase Chain Reaction; D012313:RNA; D013997:Time Factors
chemical_list: D012313:RNA; D002244:Carbon; D004247:DNA