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Journal Articles

NHEJ repair rather than HR repair is the primary function to target to enhance radiosensitization at high LET values

Takahashi, Akihisa*; Kubo, Makoto*; Igarashi, Chie*; Yoshida, Yukari*; Funayama, Tomoo; Kobayashi, Yasuhiko; Nakano, Takashi*

JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 82, 2015/03

DNA double-strand breaks (DSBs) induced by ionizing radiation pose a major threat to cell survival. The cell can respond to the presence of DSBs, through two major repair pathways: Homologous recombination (HR) and non-homologous end-joining (NHEJ). Higher levels of cell death are induced by high-LET radiation when compared to low-LET radiation, even at the same doses because of less effective or more inefficient DNA repair. In this study, we examine the effects of radiation with different LET values on DNA DSB repair and radiosensitivity. Wild-type cells and HR deficient (but NHEJ proficient) cells exhibited the high RBE values at LET values of 108 keV/$$mu$$ m. The RBE value for each cell type decreased with increasing LET values over 200 keV/$$mu$$m. Although NHEJ proficient cells had an almost constant SER value, NHEJ deficient cells showed a high SER value when compared to NHEJ proficient cells, even with increasing LET values.

Journal Articles

LET dependency of human normal dermal cells survival in carbon ion irradiation

Yoshida, Yukari*; Mizohata, Kensuke*; Matsumura, Akihiko*; Isono, Mayu*; Yako, Tomoko*; Nakano, Takashi*; Funayama, Tomoo; Kobayashi, Yasuhiko; Kanai, Tatsuaki*

JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 81, 2015/03

In the clinical application of carbon-ion (C-ion) radiation therapy in Japan, different RBE values of carbons have been used for clinical and biological endpoints. The biological RBE (bRBE) was estimated by a method that is based on the linear-quadratic (LQ) model, and was defined ${it in vitro}$ at the 10% surviving fraction of human salivary gland (HSG) tumor cells. However, many of biological parameters, that is, type of tissues, different sort of cells, oxygenation levels, and all, could affect radiosensitivity. Thus, normal human dermal fibroblasts (NHDF) cells were exposed to C-ion beams at Gunma University (10-80 keV/micrometer) and TIARA (108 and 158 keV/micrometer). The surviving fractions were analyzed with colony formation assays. The experimental RBE (eRBE) values were estimated from the radiation dose survival curve fitted by LQ model, and defined ${it in vitro}$.

Journal Articles

Nonhomologous end-joining repair plays a more important role than homologous recombination repair in defining radiosensitivity after exposure to high-LET radiation

Takahashi, Akihisa*; Kubo, Makoto*; Ma, H.*; Nakagawa, Akiko*; Yoshida, Yukari*; Isono, Mayu*; Kanai, Tatsuaki*; Ono, Tatsuya*; Furusawa, Yoshiya*; Funayama, Tomoo; et al.

Radiation Research, 182(3), p.338 - 344, 2014/09

 Times Cited Count:58 Percentile:90.24(Biology)

To clarify whether high-LET radiation inhibits all repair pathways or specifically one repair pathway, studies were designed to examine the effects of radiation with different LET values on DNA DSB repair and radiosensitivity. Embryonic fibroblasts bearing repair gene KO were exposed to X rays, carbon-, iron-, neon- and argon-ion beams. Cell survival was measured with colony-forming assays. The sensitization enhancement ratio (SER) values were calculated using the 10% survival dose of wild-type cells and repair-deficient cells. Cellular radiosensitivity was listed in descending order: double-KO cells $$>$$ NHEJ-KO cells $$>$$ HR-KO cells $$>$$ wild-type cells. Although HR-KO cells had an almost constant SER value, NHEJ-KO cells showed a high-SER value when compared to HR-KO cells, even with increasing LET values. These results suggest that with carbon-ion therapy, targeting NHEJ repair yields higher radiosensitivity than targeting homologous recombination repair.

Journal Articles

Increase in cell motility by carbon ion irradiation via the Rho signaling pathway and its inhibition by the ROCK inhibitor Y-27632 in lung adenocarcinoma A549 cells

Murata, Kazutoshi*; Noda, Shinei*; Oike, Takahiro*; Takahashi, Akihisa*; Yoshida, Yukari*; Suzuki, Yoshiyuki*; Ono, Tatsuya*; Funayama, Tomoo; Kobayashi, Yasuhiko; Takahashi, Takeo*; et al.

Journal of Radiation Research, 55(4), p.658 - 664, 2014/07

 Times Cited Count:16 Percentile:54.44(Biology)

The effect of carbon ion irradiation on cell motility through the Rho signaling pathway in the human lung adenocarcinoma cell line A549 was studied. At 48 h after irradiation, the cell motility of A549 cells became significantly greater, and the formation of protrusions significantly increased in cells irradiated with carbon ion. The observed increase in cell motility due to carbon ion irradiation was similar to that observed due to X-ray irradiation. Western-blot analysis showed that carbon ion irradiation increased P-MLC2-S19 expression compared with in unirradiated controls, while total MLC2 expression was unchanged. Exposure to a non-toxic concentration of Y-27632, a specific inhibitor of ROCK, reduced the expression of P-MLC2-S19 after C-ion irradiation, resulting in a significant reduction in migration. These data suggest that carbon irradiation increases cell motility in A549 cells via the Rho signaling pathway and that ROCK inhibition reduces that effect.

Journal Articles

Three-dimensional and multienergy $$gamma$$-ray simultaneous imaging by using a Si/CdTe Compton camera

Suzuki, Yoshiyuki*; Yamaguchi, Mitsutaka; Odaka, Hirokazu*; Shimada, Hirofumi*; Yoshida, Yukari*; Torikai, Kota*; Sato, Takahiro; Arakawa, Kazuo*; Kawachi, Naoki; Watanabe, Shigeki; et al.

Radiology, 267(3), p.941 - 947, 2013/06

 Times Cited Count:23 Percentile:63.82(Radiology, Nuclear Medicine & Medical Imaging)

Journal Articles

Synergistic effect of heat shock protein 90 inhibitor, 17-allylamino-17-demethoxygeldanamycin and X-rays, but not carbon-ion beams, on lethality in human oral squamous cell carcinoma cells

Musha, Atsushi*; Yoshida, Yukari*; Takahashi, Takeo*; Ando, Koichi*; Funayama, Tomoo; Kobayashi, Yasuhiko; Negishi, Akihide*; Yokoo, Satoshi*; Nakano, Takashi*

Journal of Radiation Research, 53(4), p.545 - 550, 2012/07

 Times Cited Count:10 Percentile:46.80(Biology)

Journal Articles

Evaluation of the relative biological effectiveness of carbon ion beams in the cerebellum using the rat organotypic slice culture system

Yoshida, Yukari*; Suzuki, Yoshiyuki*; Al-Jahdari, W. S.*; Hamada, Nobuyuki*; Funayama, Tomoo; Shirai, Katsuyuki*; Kato, Hiroyuki*; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Nakano, Takashi*

Journal of Radiation Research, 53(1), p.87 - 92, 2012/02

 Times Cited Count:8 Percentile:41.19(Biology)

Journal Articles

Three-dimensional imaging test for a head module of a Si/CdTe Compton camera for medical application

Yamaguchi, Mitsutaka; Kawachi, Naoki; Kamiya, Tomihiro; Sato, Takahiro; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; et al.

JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 145, 2012/01

no abstracts in English

Journal Articles

Development of head module for multi-head Si/CdTe Compton camera for medical applications

Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.

Nuclear Instruments and Methods in Physics Research A, 648(Suppl.1), p.S2 - S7, 2011/08

 Times Cited Count:2 Percentile:19.61(Instruments & Instrumentation)

We are constructing a three-dimensional imaging system for medical and biological applications. The system will allow simultaneous imaging at high spatial and energy resolutions across a wide energy range, from several tens of keV to a few MeV. In this work, one prototype head module have been developed for a multi-head Si/CdTe Compton camera system. The performance of the prototype was evaluated with a sealed Ba-133 radiation source. The experiments confirmed that the imaging results were consistent with actual source position. In addition to the resolution for the parallel directions to the detector surface, the position resolution was evaluated for the depth direction at a point in near region of the head-module. These position resolutions were well reproduced by Monte Carlo simulation results.

Journal Articles

Effectiveness of carbon-ion beams for apoptosis induction in rat primary immature hippocampal neurons

Kaminuma, Takuya*; Suzuki, Yoshiyuki*; Shirai, Katsuyuki*; Mizui, Toshiyuki*; Noda, Shinei*; Yoshida, Yukari*; Funayama, Tomoo; Takahashi, Takeo*; Kobayashi, Yasuhiko; Shirao, Tomoaki*; et al.

Journal of Radiation Research, 51(6), p.627 - 631, 2010/11

 Times Cited Count:9 Percentile:33.25(Biology)

Journal Articles

Counting rate performance measurement of newly developed Si/CdTe Compton camera for biological and medical applications

Yamaguchi, Mitsutaka; Kawachi, Naoki; Kamiya, Tomihiro; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.

2010 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.2004 - 2007, 2010/10

Journal Articles

Basic characteristics of a newly developed Si/CdTe Compton camera for medical imaging

Kawachi, Naoki; Watanabe, Shigeki; Sato, Takahiro; Arakawa, Kazuo; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; Aono, Hiroyuki*; Watanabe, Shin*; Yamaguchi, Mitsutaka*; Takahashi, Tadayuki*; et al.

2008 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.1540 - 1543, 2008/10

Journal Articles

Research into the radiosensitivity of normal brain tissue

Suzuki, Yoshiyuki*; Yoshida, Yukari*; Shirai, Katsuyuki*; Hamada, Nobuyuki*; Mizui, Toshiyuki*; Noda, Shinei*; Funayama, Tomoo; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Shirao, Tomoaki*; et al.

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 107, 2007/02

Journal Articles

Bystander effect of high linear energy transfer charged particle radiation on human glioblastoma cells

Ishiuchi, Shogo*; Hasegawa, Masatoshi*; Yoshida, Yukari*; Hamada, Nobuyuki*; Funayama, Tomoo; Wada, Seiichi*; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Nakano, Takashi*

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 104, 2007/02

Oral presentation

Development of Si/CdTe Compton camera for medical imaging

Yamaguchi, Mitsutaka*; Arakawa, Kazuo; Aono, Hiroyuki*; Ishikawa, Shinnosuke*; Kamiya, Tomihiro; Kawachi, Naoki; Odaka, Hirokazu*; Sakurai, Hideyuki*; Sato, Takahiro; Shimada, Hirofumi*; et al.

no journal, , 

Oral presentation

Relative biological effectiveness value of carbon ion beam to X-ray on immature hippocampal neurons in vitro

Suzuki, Yoshiyuki*; Shirai, Katsuyuki*; Mizui, Toshiyuki*; Hamada, Nobuyuki*; Noda, Shinei*; Funayama, Tomoo; Yoshida, Yukari*; Kobayashi, Yasuhiko; Shirao, Tomoaki*; Nakano, Takashi*

no journal, , 

no abstracts in English

Oral presentation

Effects of X-ray and carbon ion beam on the postnatal cerebellum in organotypic slice cultures

Yoshida, Yukari*; Suzuki, Yoshiyuki*; Takeuchi, Aiko*; Hamada, Nobuyuki*; Shirai, Katsuyuki*; Funayama, Tomoo; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Ozawa, Seiji*; Nakano, Takashi*

no journal, , 

no abstracts in English

Oral presentation

Performance characterization of a prototype Si/CdTe Compton camera

Kawachi, Naoki; Watanabe, Shigeki; Fujimaki, Shu; Ishioka, Noriko; Sato, Takahiro; Kamiya, Tomihiro; Arakawa, Kazuo; Watanabe, Shin*; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; et al.

no journal, , 

Oral presentation

Biological effectiveness of carbon ions for apoptosis induction in cultured rat premature neurons

Shirai, Katsuyuki*; Suzuki, Yoshiyuki*; Mizui, Toshiyuki*; Hamada, Nobuyuki*; Noda, Shinei*; Funayama, Tomoo; Yoshida, Yukari*; Kobayashi, Yasuhiko; Shirao, Tomoaki*; Nakano, Takashi*

no journal, , 

no abstracts in English

Oral presentation

Effect of X-ray and carbon ion beam on the postnatal cerebellum in organotypic slice culture

Yoshida, Yukari*; Suzuki, Yoshiyuki*; Hamada, Nobuyuki*; Shirai, Katsuyuki*; Al-Jahdari, W. S.*; Kobayashi, Yasuhiko; Ozawa, Seiji*; Nakano, Takashi*

no journal, , 

no abstracts in English

41 (Records 1-20 displayed on this page)