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Watanabe, Ritsuko
no journal, ,
no abstracts in English
using heavy-ion microbeamSakashita, Tetsuya; Suzuki, Michiyo; Hattori, Yuya; Ikeda, Hiroko; Muto, Yasuko; Yokota, Yuichiro; Funayama, Tomoo; Hamada, Nobuyuki*; Fukamoto, Kana*; Kobayashi, Yasuhiko
no journal, ,
We have no direct evidence for the interaction of ionizing radiation with the central neuronal tissue (nerve ring) of the nervous system in . Localized ionizing irradiation is useful to analyze radiation effects at a cellular or tissue level. Thus, to investigate the effects on the nerve ring, we used the heavy-ion microbeam system installed at the Takasaki Ion accelerators for Advanced Radiation Application of JAEA. To achieve during-learning irradiation, we have developed the live-targeting system for non-paralyzed using the micro-total analysis systems to restrict their motion, and this will be discussed.
Narita, Ayumi; Noguchi, Miho; Yokoya, Akinari; Kobayashi, Katsumi*; Fujii, Kentaro
no journal, ,
no abstracts in English
Suzuki, Michiyo; Hattori, Yuya; Sakashita, Tetsuya; Funayama, Tomoo; Yokota, Yuichiro; Muto, Yasuko; Ikeda, Hiroko; Kobayashi, Yasuhiko
no journal, ,
no abstracts in English
; A Computational approach for understanding radiation effectsHattori, Yuya; Suzuki, Michiyo; Tsuji, Toshio*; Kobayashi, Yasuhiko
no journal, ,
no abstracts in English
Ouchi, Noriyuki
no journal, ,
Chromatin fiber is the container of DNA in Cell nucleus, its structure is changed drastically depending on the cell cycle, and make 10000 times condensed structure as known as chromosome at metaphase. Here we will show the simulation results of the mathematical model of chromosome/chromatin broken ends movement which will be produced by DSB, not only its dynamics but the dependency of cell cycle, and investigate the damage effectiveness on the whole system.
Akamatsu, Ken; Shikazono, Naoya
no journal, ,
no abstracts in English
Shiraishi, Iyo; Shiina, Takuya; Sugaya, Yuki; Shikazono, Naoya; Yokoya, Akinari
no journal, ,
no abstracts in English
Shiina, Takuya; Shiraishi, Iyo; Sugaya, Yuki; Watanabe, Ritsuko; Suzuki, Masao*; Yokoya, Akinari
no journal, ,
no abstracts in English
Sugaya, Yuki; Shiina, Takuya; Shiraishi, Iyo; Fujii, Kentaro; Yokoya, Akinari
no journal, ,
no abstracts in English
Chino, Masamichi
no journal, ,
We describe the source term estimation by the combination of environmental monitoring data with atmospheric dispersion simulation and the prediction of atmospheric dispersion and deposition in local and regional areas carried out during the Fukushima Dai-ichi nuclear accident. The role of computer simulations and future research cleared through the experiences are also addressed.
Takahashi, Momoko; Shikazono, Naoya
no journal, ,
no abstracts in English
Urushibara, Ayumi; Kodama, Seiji*; Yokoya, Akinari
no journal, ,
no abstracts in English
Funayama, Tomoo; Yokota, Yuichiro; Ikeda, Hiroko; Kobayashi, Yasuhiko
no journal, ,
When cells are irradiated with a few Gy of high-LET ions, the heterogeneous mixture comprising nonhit, single-hit, and multihit cells in the same population arise in the cell population and it makes difficult to evaluate the accurate cellular effects of heavy ions. More over, the response of the cell population is modified by bystander response in such situation. Target irradiation of individual cells with heavy-ion microbeam is a useful means for analyze such a complicated situation. In this talk, we will introduce the potential of heavy-ion microbeam system of JAEA-Takasaki, and outline of our research using it.
Ikeda, Hiroko; Funayama, Tomoo; Yokota, Yuichiro; Kanai, Tatsuaki*; Kobayashi, Yasuhiko
no journal, ,
We have so far analyzed bystander effects between lung cancer cells H1299/wt
and lung normal cells WI-38, using clonogenic assay to judge reproductive cell death. Consequently, when the kinds of irradiated cells differed, it found out that heavy-ion induced bystander responses change a lot. In this research, we decided to use the heavy-ion microbeam system at JAEA-Takasaki to clarify inner cellular and/or intercellular molecular mechanisms concerned with the bystander effects. This equipment is an effective tool and it enabled to elucidate mechanisms which were not made clearly in our previous study using broad beam system. Although there are many reports of bystander effects between the same type cells using microbeam, since there is still no report of bystander effects between different type cells using heavy-ion microbeam, the establishment of experimental system is needed. Now, we are constructing experimental systems to irradiate a part of cells which carried out mixed culture in the same plate using microbeam, and we will report the acquired findings and future development.
Yokoya, Akinari; O'Neill, P.*
no journal, ,
Yokoya, Akinari; Noguchi, Miho; Kaminaga, Kiichi; Sakamoto, Yuka; Kanari, Yukiko; Narita, Ayumi; Fujii, Kentaro
no journal, ,
no abstracts in English
Noguchi, Miho; Kanari, Yukiko; Kaminaga, Kiichi; Sakamoto, Yuka; Narita, Ayumi; Fujii, Kentaro; Yokoya, Akinari
no journal, ,
Most studies of radiation induced biological effect starts from nuclear DNA damage. However, in the case of low dose irradiation, recent reports suggest that extranuclear targets, such as in cytoplasm, may have a role in mediating some important effects of radiation. Cellular effect of cytoplasmic irradiation remains to be elucidated. Mitochondria spread throughout the entire cytoplasm and contain their own genome, and mediate essential cell functions, such as generation of ATP and regulation of cell death. Mitochondria are main source of oxidative stress to generate ROS as by-product of respiration for ATP production. In addition, dysfunctions of mitochondria are involved in a wide variety of diseases. Mitochondrial functions are indispensable for survival. However, radiation effect of mitochondrial functions is not clear. In order to clarify what effects ionizing radiation leads to mitochondrial functions, we first examined the effects of ionizing radiation on mitochondrial morphology in mammalian cells. Mitochondria are dynamic organelles that continuously fuse and divide in response to environment and cellular differentiation. It is known that mitochondrial morphology dynamically change with cell cycle progression. In this study, after irradiation, we labeled mitochondria by Mitotracker Red and analyzed kinetics of mitochondrial morphology for 4 days by live-cell imaging techniques. Cell cycle stages were identified by nuclei staining. We reports the relation between radiation induced cell cycle arrest and mitochondrial dynamics.
Igarashi, Shosuke; Onuki, Toshihiko; Sakamoto, Fuminori
no journal, ,
We have found specific base positions in the DNA cleavage by the irradiation of X-rays after association of a cisplatin with DNA. In cancer therapy it is well known that application of X-rays radiation with cisplatin dosage enhances the anti-cancer effect. However, the mechanism of enhancement in the anti-cancer has not been elucidated in the level of DNA base. We have developed a new approach for the determination of the DNA cleavage position using the Sanger method. Here we have specified the positions of base cleaved by X-ray radiation with cisplatin association with DNA. The cleavage patterns of the DNA irradiated by X-ray show that the DNA was cleaved by 100 Gy irradiation, and the four kinds of bases were cleaved. Ciplatin associated DNA without the irradiation was not cleaved. On the other hand, the ciplatin associated DNA specifically enhanced the cleavage at the bases of "guanine" and "adenine". When the irradiation increased to 150 Gy, the specific cleavage at the "guanine" and "adenine" were still detected. These results indicate that supra-additive effect by cisplatin association and X-ray irradiation on the DNA damage was caused by the specific cleavage at the base positions of "guanine" and "adenine".