Effect of heavy ion irradiation on optical property of radiation-crosslinked hydroxypropyl cellulose gel containing methacrylate monomers

Hiroki, Akihiro; Yamashita, Shinichi*; Kimura, Atsushi; Nagasawa, Naotsugu; Taguchi, Mitsumasa

Nuclear Instruments and Methods in Physics Research B, 365(Part B), p.583 - 586, 2015/12

Effects of liner energy transfer (LET) and dose rate on the optical property of polymer gel dosimeters were investigated. The dosimeter prepared by using a radiation-crosslinked hydroxypropyl cellulose gel and methacrylate monomers such as 2-hydroxyethyl methacrylate and nonaethylene glycol dimethacrylate showed the color change from colorless to white with the He, C, Fe ions irradiation. Absorbance of the irradiated dosimeters increased with the dose up to 10 Gy. The absorbance of the dosimeters at the same total dose decreased with increasing dose rate in the range of 0.1 to 6.8 Gy/min. The absorbance decreased in order of He, C, Fe ions, which was in agreement with a change of LET. The increase in LET affected the decrease in the number of polymerization initiator such as OH radical and hydrated electron, resulting in the reduction of the absorbance of the dosimeters.

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

https://doi.org/10.11484/jaea-review-2014-050

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 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 .

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

https://doi.org/10.1093/jrr/rru002

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.

Heavy-ion microbeam cell irradiation system at JAERI-Takasaki

Kobayashi, Yasuhiko; Funayama, Tomoo; Wada, Seiichi; Sakashita, Tetsuya; Kakizaki, Takehiko; Hamada, Nobuyuki*; Yokota, Yuichiro; Furusawa, Yoshiya*

KEK Proceedings 2005-5, p.6 - 8, 2005/10

no abstracts in English

System of cell irradiation with a precise number of heavy ions

Kobayashi, Yasuhiko; Funayama, Tomoo; Wada, Seiichi*; Taguchi, Mitsumasa; Watanabe, Hiroshi

Radiation Research, 161(1), p.90 - 91, 2004/01

A single cell irradiation system has been developed for targeting cells individually with a precise number of heavy ions to elucidate radiobiological effects of exactly one particle and to investigate the biological effects of low fluence irradiation with HZE particles. Using the heavy ion microbeam apparatus installed at JAERI-Takasaki, mammalian cells were irradiated in the atmosphere with a single or precise numbers of ions, 13.0 MeV/u 20Ne or 11.5 MeV/u 40Ar. The number of ions traversed the cells attached on the ion track detector CR-39 were counted with a plastic scintillator. Immediately after the irradiation, the position and the number of ion tracks traversed the cell was detected with etching of CR-39 from the opposite side of the cell with alkaline-ethanol solution at 37C. The growths of the cells were observed individually up to 60 hours after irradiation.

Properties of TNF-1 track etch detector

Ogura, K.*; Asano, Masaharu; Yasuda, Nakahiro*; Yoshida, Masaru

Nuclear Instruments and Methods in Physics Research B, 185(1-4), p.222 - 227, 2001/12

https://doi.org/10.1016/S0168-583X(01)00816-3

no abstracts in English

Atomic collision physics relevant to the treatment planning system for heavy particle cancer therapy; Radial dose simulations

Moribayashi, Kengo

no journal, , 

Simulation of radiation-induced clustered DNA damage

Watanabe, Ritsuko

no journal, , 

no abstracts in English

Dose response of polymer gel dosimeter based on hydroxypropyl cellulose hydrogel; Toward the application on heavy ion therapy

Hiroki, Akihiro; Yamashita, Shinichi*; Kimura, Atsushi; Nagasawa, Naotsugu; Taguchi, Mitsumasa

no journal, , 

The polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate, nonaethylene glycol dimethacrylate, and tetrakis (hydroxymethyl) phosphoniumu chloride with radiation-crosslinked hydroxypropyl cellulose gel were irradiated with 290 MeV/u C ions at HIMAC. Absorbance of the irradiated dosimeters at 660 nm increased with an increase in the dose up to 10 Gy. The dose response of the dosimeter irradiated with C ions was about 0.007 Abs. Gy, which decreased in about one-tenth of the -irradiated sample. RGB value of the image obtained by using a flat-bed image scanner also increased with increasing dose. Distribution of the dose estimated from RGB value of the scanned image was almost agreement with that of a general radiochromic film for the radiotherapy.

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

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

no journal, , 

This study aimed to investigate the effect of carbon ion (C-ion) irradiation on cell motility through the ras homolog gene family member (Rho) signaling pathway in the human lung adenocarcinoma cell line A549. Cell motility was assessed by a wound-healing assay, and the formation of cell protrusions was evaluated by F-actin staining. Cell viability was examined by the WST-1 assay. The expression of myosin light chain 2 (MLC2) and the phosphorylation of MLC2 at Ser19 (P MLC2-S19) were analyzed by Western blot. The data suggest that C-ion irradiation increases cell motility in A549 cells via the Rho signaling pathway and that ROCK inhibition reduces that effect.