| Project/Area Number |
13490007
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
広領域
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| Research Institution | The University of Tokyo |
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Principal Investigator |
TAGO Masao (2003) The University of Tokyo, Faculty of Medicine, Lecturer, 医学部附属病院, 講師 (50282520)
篠原 邦夫 (2001-2002) 東京大学, 大学院・医学系研究科, 教授 (10112088)
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| Co-Investigator(Kenkyū-buntansha) |
KODAMA Ryosuke Osaka University, Institute of Laser Engineering, Associate Professor, レーザー核融合研究センター, 助教授 (80211902)
NAKANO Hisako The Tokyo Metropolitan Institute of Medical Science, Department of Laboratory Animal Science, Researcher, 東京都臨床医学総合研究所, 研究員 (20172372)
多胡 正夫 東京大学, 医学部附属病院, 講師 (50282520)
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| Project Period (FY) |
2001 – 2003
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| Project Status |
Completed (Fiscal Year 2003)
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| Budget Amount *help |
¥7,600,000 (Direct Cost: ¥7,600,000)
Fiscal Year 2003: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2002: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2001: ¥3,500,000 (Direct Cost: ¥3,500,000)
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| Keywords | ultra high dose rate X-ray / cell death / radiation sensitivity / laser-plasma X-ray / 超高線量率 / 0.5psecパルス / ガラス線量計 / L5178Y / M10 |
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| Research Abstract |
There have been no observations on the effects of radiation delivered at even higher dose rates on the picosecond time-scale. Here we examined, for the first time, the effects on cultured mouse L5178Y cells and its radiosensitive XRCC4-deficient mutant M10 cells of sub-picosecond pulse X-rays emitted from laser-produced plasmas at ultra high dose rate of 10^<12>-10^<13> Gy/sec. Results are as follows.
1. No increase in the sensitivity to the sub-picosecond X-rays was observed compared with y-rays at a conventional dose-rate.
2. The increase in the sensitivity of L5178Y cells by labeling with 5-iododeoxyuridine (IUdR) was smaller than those irradiated with y-rays at a conventional dose-rate, while the difference was apparently reverse in M10 cells. These results suggest that there is different mechanism in indirect action of X-rays between ultra high dose rate and conventional dose rate.
It is desired to establish sophisticated experimental systems and to examine the effects of sub-picosecond X-rays further.
In addition, the application to clinical medicine is also expected. Obtaining cardiac CT images and/or stereotactic irradiation for lung tumors using sub-picosecond X-rays would be possible in the future.
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