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Saika, Hiroaki*; Mikami, Masafumi*; Endo, Masaki*; Sakamoto, Ayako; Toki, Seiichi*
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 97, 2016/02
Watanabe, Kazuyo*; Akitsuki, Takashi*; Shimura, Sachiko*; Gusev, O.*; Cornette, R.*; Kikawada, Takahiro*; Sakashita, Tetsuya; Funayama, Tomoo; Kobayashi, Yasuhiko; Okuda, Takashi*
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 87, 2015/03
The Sleeping Chironomid, can stand complete desiccation (anhydrobiosis) and also shows radio-resistance. Recently, we have generated cultured cell (Pv11) originated from embryo which can also stand complete dehydration. In this study, we examine the tolerance of cultured cell Pv11 against ionbeam irradiation.
Horikawa, Daiki*; Yamaguchi, Ayami*; Sakashita, Tetsuya; Tanaka, Daisuke*; Hamada, Nobuyuki*; Yukuhiro, Fumiko*; Kuwahara, Hirokazu*; Kunieda, Takekazu*; Watanabe, Masahiko*; Nakahara, Yuichi*; et al.
Astrobiology, 12(4), p.283 - 289, 2012/04
Times Cited Count:23 Percentile:68.44(Astronomy & Astrophysics)We examined the hatchability of hydrated and anhydrobiotic eggs of the tardigrade to hatch after ionizing irradiation (helium ions), extremely low and high temperatures, and high vacuum. Anhydrobiotic eggs (50% lethal dose; 1690 Gy) were substantially more radioresistant than hydrated ones (50% lethal dose; 509 Gy). Anhydrobiotic eggs also have a broader temperature resistance compared with hydrated ones. Over 70% of the anhydrobiotic eggs treated at high and low temperatures, but all of the hydrated eggs failed to hatch. After exposure to high vacuum conditions, the hatchability of the anhydrobiotic eggs was comparable to that of untreated control eggs.
Gusev, O.*; Nakahara, Yuichi*; Vanyagina, V.*; Malutina, L.*; Cornette, R.*; Sakashita, Tetsuya; Hamada, Nobuyuki*; Kikawada, Takahiro*; Kobayashi, Yasuhiko; Okuda, Takashi*
PLoS ONE (Internet), 5(11), p.e14008_1 - e14008_9, 2010/11
Times Cited Count:52 Percentile:75.53(Multidisciplinary Sciences)Anhydrobiotic chironomid larvae can withstand prolonged complete desiccation as well as other external stresses including ionizing radiation. To understand the cross-tolerance mechanism, we have analyzed the damage and repair in the nuclear DNA using DNA comet assays and gene expression in relation to anhydrobiosis and radiation. We found that dehydration causes alterations in chromatin structure and a severe fragmentation of nuclear DNA in the cells of the larvae despite successful anhydrobiosis. Furthermore, while the larvae have restored physiological activity within an hour following rehydration, nuclear DNA restoration typically took 72 to 96 h.
Yamaguchi, Hiroyasu*; Shimizu, Akemi*; Hase, Yoshihiro; Degi, Konosuke*; Tanaka, Atsushi; Morishita, Toshikazu*
Euphytica, 165(1), p.97 - 103, 2009/01
Times Cited Count:29 Percentile:76.28(Agronomy)We compared the effects of ion-beam and -ray irradiation on mutation induction in axillary buds of chrysanthemum, and analyzed the chimeric structure of the resulting mutants. Axillary buds were irradiated with carbon ions (mean LET 122 keV/m), helium ions (9 keV/m), and rays. The lower five nodes of shoots elongating from the irradiated buds were cut one by one, and new shoots were allowed to grow. This procedure was repeated twice and flower color mutation was investigated. Chimeric structure was analyzed by comparing the flower color of mutants to that of plants regenerated from the roots. All the flower color mutants induced with rays were periclinal chimeras. In contrast, some mutants obtained with ion beams had the same flower color as that of the plants derived from the roots. This suggests that they were solid mutants, where both LI and LIII tissues were derived from the same mutated cell.
Horikawa, Daiki*; Kunieda, Takekazu*; Abe, Wataru*; Watanabe, Masahiko*; Nakahara, Yuichi*; Yukuhiro, Fumiko*; Sakashita, Tetsuya; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; et al.
Astrobiology, 8(3), p.549 - 556, 2008/06
Times Cited Count:96 Percentile:91.30(Astronomy & Astrophysics)We report the successful rearing of the herbivorous tardigrade, , by supplying the green alga as food. The life span was 35 d, deposited eggs required 5.7 d to hatch, and animals began to deposit eggs 9 d after hatching. The reared individuals of this species had an anhydrobiotic capacity throughout their life cycle in egg, juvenile, and adult stages. Furthermore, the reared adults in an anhydrobiotic state were tolerant of temperatures of 90C and -196C and exposure to 99.8% acetonitrile or irradiation with 4000 Gy He ions. Based on their life history traits and tolerance to extreme stresses, might be a suitable model for astrobiological studies of multicellular organisms.
Nakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 72, 2008/03
no abstracts in English
Nakahara, Yuichi*; Watanabe, Masahiko*; Kikawada, Takahiro*; Fujita, Akihiko*; Horikawa, Daiki*; Okuda, Takashi*; Sakashita, Tetsuya; Funayama, Tomoo; Hamada, Nobuyuki*; Wada, Seiichi*; et al.
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 113, 2008/03
We have shown that anhydrobiotic larvae of have higher tolerance against both high linear energy transfer (LET) radiation than hydrated larvae. We therefore examined effects of high-LET radiation on four kinds of larvae: (1) normal hydrated (intact) larva, (2) intermediates between the anhydrobiotic and normal hydrated state, (3) almost completely dehydrated (anhydrobiotic) larvae, and (4) immediately rehydrated larvae that are assumed to have a similar molecular profile to anhydrobiotic larvae. The intermediates and immediately rehydrated larvae survived longer after high-LET radiation than intact larvae, indicating that radiation tolerance could be enhanced even in hydrated larvae. Physiological changes toward anhydrobiosis, e.g. accumulation of protectants or increasing damage repair capacity, correlate with improved radiation tolerance in hydrated larvae.
Watanabe, Masahiko*; Nakahara, Yuichi*; Sakashita, Tetsuya; Kikawada, Takahiro*; Fujita, Akihiko*; Hamada, Nobuyuki*; Horikawa, Daiki*; Wada, Seiichi*; Kobayashi, Yasuhiko; Okuda, Takashi*
Journal of Insect Physiology, 53(6), p.573 - 579, 2007/06
Times Cited Count:20 Percentile:64.96(Entomology)We examined effects of high-LET radiation on 4 kinds of larvae: (1) normal hydrated (intact) larva, (2) intermediates between the anhydrobiotic and normal hydrated state, (3) almost completely dehydrated (anhydrobiotic) larvae, and (4) immediately-rehydrated larvae that are assumed to have a similar molecular profile to anhydrobiotic larvae. The intermediates and immediately-rehydrated larvae survived longer after high-LET radiation than intact larvae, indicating that radiation tolerance could be enhanced even in hydrated larvae. Physiological changes toward anhydrobiosis, e.g. accumulation of protectants or increasing damage repair capacity, correlate with improved radiation tolerance in hydrated larvae. In addition, almost complete desiccation further enhanced radiation tolerance, possibly in a different way from the hydrated larvae.
Horikawa, Daiki*; Sakashita, Tetsuya; Katagiri, Chihiro*; Watanabe, Masahiko*; Kikawada, Takahiro*; Nakahara, Yuichi*; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; Higashi, Seigo*; et al.
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 116, 2007/02
no abstracts in English
Morita, Ryohei*; Morishita, Toshikazu*; Nakagawa, Hitoshi*; Nishimura, Minoru*; Yamaguchi, Hiroyasu*; Yokota, Yuichiro; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 78, 2007/02
no abstracts in English
Horikawa, Daiki*; Sakashita, Tetsuya; Katagiri, Chihiro*; Watanabe, Masahiko*; Kikawada, Takahiro*; Nakahara, Yuichi*; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; Higashi, Seigo*; et al.
International Journal of Radiation Biology, 82(12), p.843 - 848, 2006/12
Times Cited Count:132 Percentile:99.15(Biology)no abstracts in English
Watanabe, Masahiko*; Sakashita, Tetsuya; Fujita, Akihiko*; Kikawada, Takahiro*; Nakahara, Yuichi*; Hamada, Nobuyuki*; Horikawa, Daiki*; Wada, Seiichi*; Funayama, Tomoo; Kobayashi, Yasuhiko; et al.
International Journal of Radiation Biology, 82(12), p.835 - 842, 2006/12
Times Cited Count:19 Percentile:77.36(Biology)The aim of this study is to characterize the tolerance to high-LET radiations of. Larval survival and subsequent metamorphoses were compared between anhydrobiotic (dry) and non-anhydrobiotic (wet) samples after exposure to 1 to 7000 Gy of three types of heavy ions with LET values ranging from 16.2 to 321 keV/m. At all LET values measured, dry larvae consistently showed greater radiation tolerance than hydrated larvae, due to the disaccharide trehalose in anhydrobiotic animals. Relative biological effectiveness (RBE) values based on the median inhibitory doses reached a maximum at 116 keV/m (C). Anhydrobiosis potentiates radiation tolerance in terms of larval survival, pupation and adult emergence of exposed to high-LET radiations. larvae might have more efficient DNA damage repair after radiation than other chironomid species.
Watanabe, Masahiko*; Sakashita, Tetsuya; Fujita, Akihiko*; Kikawada, Takahiro*; Horikawa, Daiki*; Nakahara, Yuichi*; Wada, Seiichi*; Funayama, Tomoo; Hamada, Nobuyuki*; Kobayashi, Yasuhiko; et al.
International Journal of Radiation Biology, 82(8), p.587 - 592, 2006/08
Times Cited Count:35 Percentile:89.90(Biology)The present study aims to evaluate effects of anhydrobiosis on radiation tolerance in an anhydrobiotic insect, Polypedilum vanderplanki. Larval survival (48 h), anhydrobiotic ability, metamorphosis and reproduction after exposure to 1 to 9000 Gy of -rays at the larval stage were comparedbetween anhydrobiotic (dry) and normal (wet) phases. Wet larvae were killed in a dose-dependent manner at doses higher than 2000 Gy, and all died within 8 h after 4000 Gy exposure. In contrast, dry larvae survived even 5000 Gy, and some of them still tolerated 7000 Gy and were alive at 48 h after rehydration. Moreover, greater radiotolerance of dry larva, compared to wet ones, was demonstrated interms of metamorphoses. However, anhydrobiosis did not protect against radiation damage in terms of producing viable offspring. These results indicate that anhydrobiosis enhances radiotolerance, resulting in increases of successful metamorphoses.
Naito, Ken*; Kusaba, Makoto*; Shikazono, Naoya; Takano, Toshiya*; Tanaka, Atsushi; Tanisaka, Takatoshi*; Nishimura, Minoru*
Genetics, 169(2), p.881 - 889, 2005/02
Times Cited Count:108 Percentile:87.94(Genetics & Heredity)no abstracts in English
Morita, Ryuhei*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Yokota, Yuichiro; Hase, Yoshihiro; Nishimura, Minoru*
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Takano, Nao*; Yamamoto, Mitsuru*; Takahashi, Yuko*; Teranishi, Mika*; Sakamoto, Ayako; Hase, Yoshihiro; Tanaka, Atsushi; Wu, J.*; Matsumoto, Takashi*; Toki, Seiichi*; et al.
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Saika, Hiroaki*; Yoshihara, Ryohei; Sakamoto, Ayako; Toki, Seiichi*
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Hidema, Jun*; Teranishi, Mika*; Toki, Seiichi*; Saika, Hiroaki*; Sakamoto, Ayako; Yoshihara, Ryohei
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Nishimura, Minoru*; Morita, Ryuhei*; Yamaguchi, Hiroyasu*; Hase, Yoshihiro
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no abstracts in English