OKAYASU Ryuichi

J-GLOBAL         Last updated: Jul 28, 2018 at 22:32
 
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Name
OKAYASU Ryuichi
E-mail
okayasu.ryuichiqst.go.jp
Affiliation
National Institutes for Quantum and Radiological Science and Technology
Section
National Institute of Radiological Sciences
Job title
Collaborative Researcher
Degree
Ph.D.(Doctor of Philosophy)(Colorado State University(USA))
Other affiliation
Colorado State University
Research funding number
50356135

Profile

1970-1974: Tokyo University of Science (B.S. in Physics, 1974)
(1974-1978: High School Science Teacher)
1978-1980: University of Oregon, Dept. of Physics (M.S. in Physics, 1980)
1980-1981: University of California, Berkeley (Biophysics dept.)
1981-1986: Colorado State University
1987: Ph.D. in Radiation biology, Colorado State University
1987-1993: Post-doctoral fellow/Research Associate, Thomas Jefferson University, PA/MD Anderson Cancer Center, TX
1994-1995:Associate Research Scientist, Columbia University, NY
1995-1998:Assistant Professor, Univ. of Texas Medical Branch, Galveston, TX
1998-2002:Assistant Professor, Colorado State University, CO
2002-2005: Team leader, International Space Radiation Laboratory (ISRL), National Institute of Radiological Sciences (NIRS)
2005-2006: Director, ISRL, NIRS
2006-2011: Director, Heavy-Ion Radiobiology Research Group, NIRS
2009-2011: Unit leader, International Open Laboratory, Particle Radiation Molecular Biology Unit, NIRS
(2011: Mandatory Retirement at age 60)
2011-2014: Scientific Secretary/Res Scientist, International Open laboratory,NIRS
2014-2016: Senior Researcher, Res Center for Radiation Protection, NIRS
2016-present: Collaborative Researcher, QST/NIRS
2002-present: Faculty Affiliate, Colorado State University

Main interests: Cancer Biology, Radiation Biology, Biochemistry, Cell Biology, DNA repair, Toxicology

Research Areas

 
 

Academic & Professional Experience

 
Apr 2014
 - 
Mar 2016
Senior Researcher, Res Center for Radiation Protection, National Institute of Radiological Sciences
 
Apr 2011
 - 
Mar 2014
Scientific Secretary/Research Sceintist, International Open Laboratory, National Institute of Radiological Sciences
 
Apr 2006
 - 
Mar 2011
Director, Heavy-ion Radiobiology Res. Group, National Institute of Radiological Sciences
 
1995
 - 
1998
Assistant Professor, University of Texas Medical
 
 
   
 
Branch
 
1998
 - 
2002
Assistant Professor, Colorado State University
 
2002
   
 
- National Institute of Radiological Science, Team Leader
 

Education

 
 
 - 
1987
Radiation Biology, Radiology & Radiation Biology, Colorado State University
 
 
 - 
1974
Physics, Faculty of Science, Tokyo University of Science
 

Published Papers

 
Yasuda T, Kagawa W, Ogi T, Kato TA, Suzuki T, Dohmae N, Takizawa K, Nakazawa Y, Genet MD, Saotome M, Hama M, Konishi T, Nakajima NI, Hazawa M, Tomita M, Koike M, Noshiro K, Tomiyama K, Obara C, Gotoh T, Ui A, Fujimori A, Nakayama F, Hanaoka F, Sugasawa K, Okayasu R, Jeggo PA, Tajima K
PLoS genetics   14(3) e1007277   Mar 2018   [Refereed]
Sunada S, Hirakawa H, Fujimori A, Uesaka M, Okayasu R
Radiation research   188(5) 591-594   Nov 2017   [Refereed]
Allen CP, Hirakawa H, Nakajima NI, Moore S, Nie J, Sharma N, Sugiura M, Hoki Y, Araki R, Abe M, Okayasu R, Fujimori A, Nickoloff JA
Radiation research   188(1) 82-93   Jul 2017   [Refereed]
Moeller R, Raguse M, Leuko S, Berger T, Hellweg CE, Fujimori A, Okayasu R, Horneck G, STARLIFE Research Group.
Astrobiology      Feb 2017   [Refereed]
Fujisawa H, Fujimori A, Okayasu R, Uesaka M, Yajima H
Mutation research   771 36-44   Jan 2015   [Refereed]
Lee Y, Sunada S, Hirakawa H, Fujimori A, Nickoloff JA, Okayasu R
Molecular cancer therapeutics   16(1) 16-24   Jan 2017   [Refereed]
Lee Y, Li HK, Masaoka A, Sunada S, Hirakawa H, Fujimori A, Nickoloff JA, Okayasu R
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology   121(1) 162-168   Oct 2016   [Refereed]
Nakajima NI, Hagiwara Y, Oike T, Okayasu R, Murakami T, Nakano T, Shibata A
PloS one   10(3) e0122582   Mar 2015   [Refereed]
Sunada S, Kanai H, Lee Y, Yasuda T, Hirakawa H, Liu C, Fujimori A, Uesaka M, Okayasu R
Cancer science   107(9) 1250-1255   Sep 2016   [Refereed]
Hirai T, Saito S, Fujimori H, Matsushita K, Nishio T, Okayasu R, Masutani M
Biochemical and biophysical research communications   478(1) 234-240   Sep 2016   [Refereed]
Fujimori H, Sato A, Kikuhara S, Wang J, Hirai T, Sasaki Y, Murakami Y, Okayasu R, Masutani M
Scientific reports   5 18231   Dec 2015   [Refereed]
Allen CP, Tinganelli W, Sharma N, Nie J, Sicard C, Natale F, King M 3rd, Keysar SB, Jimeno A, Furusawa Y, Okayasu R, Fujimori A, Durante M, Nickoloff JA
Frontiers in oncology   5 260   Dec 2015   [Refereed]
Fujisawa H, Nakajima NI, Sunada S, Lee Y, Hirakawa H, Yajima H, Fujimori A, Uesaka M, Okayasu R
Radiation oncology (London, England)   10 175   Aug 2015   [Refereed]
Hirakawa H, Fujisawa H, Masaoka A, Noguchi M, Hirayama R, Takahashi M, Fujimori A, Okayasu R
Cancer medicine   4(3) 426-436   Mar 2015   [Refereed]
Xue L, Furusawa Y, Okayasu R, Miura M, Cui X, Liu C, Hirayama R, Matsumoto Y, Yajima H, Yu D
DNA repair   25 72-83   Jan 2015   [Refereed]
Takahashi M, Hirakawa H, Yajima H, Izumi-Nakajima N, Okayasu R, Fujimori A
International journal of radiation biology   90(12) 1125-1132   Dec 2014   [Refereed]
Sato K, Imai T, Okayasu R, Shimokawa T
Radiation research   182(4) 408-419   Oct 2014   [Refereed]
Kinashi Y, Okumura K, Kubota Y, Kitajima E, Okayasu R, Ono K, Takahashi S
Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine   88 81-85   Jun 2014   [Refereed]
Segawa T, Fujii Y, Tanaka A, Bando S, Okayasu R, Ohnishi K, Kubota N
International journal of molecular medicine   33(3) 559-564   Mar 2014   [Refereed]
Moeller R, Raguse M, Reitz G, Okayasu R, Li Z, Klein S, Setlow P, Nicholson WL
Applied and environmental microbiology   80(1) 104-109   Jan 2014   [Refereed]
Hirayama R, Ito A, Noguchi M, Matsumoto Y, Uzawa A, Kobashi G, Okayasu R, Furusawa Y
Radiation research   180(5) 514-523   Nov 2013   [Refereed]
Yajima H, Fujisawa H, Nakajima NI, Hirakawa H, Jeggo PA, Okayasu R, Fujimori A
DNA repair   12(11) 936-946   Sep 2013   [Refereed]
Hirayama R, Uzawa A, Takase N, Matsumoto Y, Noguchi M, Koda K, Ozaki M, Yamashita K, Li H, Kase Y, Matsufuji N, Koike S, Masunaga S, Ando K, Okayasu R, Furusawa Y
Mutation research   756(1-2) 146-151   Aug 2013   [Refereed]
Liu C, Kawata T, Furusawa Y, Zhou G, Inoue K, Fukada J, Kota R, George K, Cucinotta F, Okayasu R
Mutation research   756(1-2) 101-107   Aug 2013   [Refereed]
Shimizu N, Nakajima NI, Tsunematsu T, Ogawa I, Kawai H, Hirayama R, Fujimori A, Yamada A, Okayasu R, Ishimaru N, Takata T, Kudo Y
The Journal of biological chemistry   288(24) 17238-17252   Jun 2013   [Refereed]
Fujii Y, Genet MD, Roybal EJ, Kubota N, Okayasu R, Miyagawa K, Fujimori A, Kato TA
Oncology reports   29(6) 2133-2139   Jun 2013   [Refereed]
Fujii Y, Yurkon CR, Maeda J, Genet SC, Okayasu R, Kitamura H, Fujimori A, Kato TA
International journal of radiation biology   89(6) 401-410   Jun 2013   [Refereed]
Shirai H, Fujimori H, Gunji A, Maeda D, Hirai T, Poetsch AR, Harada H, Yoshida T, Sasai K, Okayasu R, Masutani M
Biochemical and biophysical research communications   435(1) 100-106   May 2013   [Refereed]
Okumura K, Kinashi Y, Kubota Y, Kitajima E, Okayasu R, Ono K, Takahashi S
Journal of radiation research   54(1) 70-75   Jan 2013   [Refereed]
Nakajima NI, Brunton H, Watanabe R, Shrikhande A, Hirayama R, Matsufuji N, Fujimori A, Murakami T, Okayasu R, Jeggo P, Shibata A
PloS one   8(8) e70107   2013   [Refereed]
Hirai T, Shirai H, Fujimori H, Okayasu R, Sasai K, Masutani M
Cancer science   103(6) 1045-1050   Jun 2012   [Refereed]
Okayasu R
International journal of cancer. Journal international du cancer   130(5) 991-1000   Mar 2012   [Refereed]
Kato TA, Okayasu R, Jeggo PA, Fujimori A
International journal of radiation biology   87(12) 1189-1195   Dec 2011   [Refereed]
Ohara M, Kimura S, Tanaka A, Ohnishi K, Okayasu R, Kubota N
International journal of molecular medicine   28(6) 1043-1047   Dec 2011   [Refereed]
Kato TA, Tsuda A, Uesaka M, Fujimori A, Kamada T, Tsujii H, Okayasu R
Radiation oncology (London, England)   6 116   Sep 2011   [Refereed]
Kinashi Y, Takahashi S, Kashino G, Okayasu R, Masunaga S, Suzuki M, Ono K
Radiation oncology (London, England)   6 106   Sep 2011   [Refereed]
Moeller R, Setlow P, Pedraza-Reyes M, Okayasu R, Reitz G, Nicholson WL
Journal of bacteriology   193(11) 2875-2879   Jun 2011   [Refereed]
Anzai K, Sekine-Suzuki E, Ueno M, Okamura M, Yoshimi H, Dan S, Yaguchi S, Enami J, Yamori T, Okayasu R
Cancer science   102(6) 1176-1180   Jun 2011   [Refereed]
Cui X, Oonishi K, Tsujii H, Yasuda T, Matsumoto Y, Furusawa Y, Akashi M, Kamada T, Okayasu R
Cancer research   71(10) 3676-3687   May 2011   [Refereed]
Hirayama R, Uzawa A, Matsumoto Y, Noguchi M, Kase Y, Takase N, Ito A, Koike S, Ando K, Okayasu R, Furusawa Y
Radiation protection dosimetry   143(2-4) 508-512   Feb 2011   [Refereed]
Tsuruoka C, Furusawa Y, Anzai K, Okayasu R, Suzuki M
Mutation research   701(1) 47-51   Aug 2010   [Refereed]
Moeller R, Reitz G, Berger T, Okayasu R, Nicholson WL, Horneck G
Astrobiology   10(5) 509-521   Jun 2010   [Refereed]
Fujii Y, Kato TA, Ueno A, Kubota N, Fujimori A, Okayasu R
Mutation research   699(1-2) 58-61   Jun 2010   [Refereed]
Fujii Y, Kato T, Kubota N, Fujimori A, Niwa O, Okayasu R
Oncology reports   23(1) 199-203   Jan 2010   [Refereed]
Hamada N, Imaoka T, Masunaga S, Ogata T, Okayasu R, Takahashi A, Kato TA, Kobayashi Y, Ohnishi T, Ono K, Shimada Y, Teshima T
Journal of radiation research   51(4) 365-383   2010   [Refereed]
Xue L, Yu D, Furusawa Y, Okayasu R, Tong J, Cao J, Fan S
Mutation research   670(1-2) 15-23   Nov 2009   [Refereed]
Xue L, Yu D, Furusawa Y, Cao J, Okayasu R, Fan S
International journal of radiation oncology, biology, physics   75(1) 235-243   Sep 2009   [Refereed]
Yu D, Sekine-Suzuki E, Xue L, Fujimori A, Kubota N, Okayasu R
International journal of cancer. Journal international du cancer   125(5) 1205-1211   Sep 2009   [Refereed]
Kato TA, Okayasu R, Bedford JS
Journal of cellular physiology   219(3) 760-765   Jun 2009   [Refereed]
Hirayama R, Ito A, Tomita M, Tsukada T, Yatagai F, Noguchi M, Matsumoto Y, Kase Y, Ando K, Okayasu R, Furusawa Y
Radiation research   171(2) 212-218   Feb 2009   [Refereed]
Sekine-Suzuki E, Yu D, Kubota N, Okayasu R, Anzai K
Biochemical and biophysical research communications   377(2) 341-345   Dec 2008   [Refereed]
Cui X, Okayasu R
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association   46(12) 3646-3650   Dec 2008   [Refereed]
Tsuruoka C, Suzuki M, Hande MP, Furusawa Y, Anzai K, Okayasu R
Radiation research   170(2) 163-171   Aug 2008   [Refereed]
Fujimori A, Yaoi T, Ogi H, Wang B, Suetomi K, Sekine E, Yu D, Kato T, Takahashi S, Okayasu R, Itoh K, Fushiki S
Biochemical and biophysical research communications   369(3) 953-957   May 2008   [Refereed]
Yu D, Sekine E, Fujimori A, Ochiya T, Okayasu R
Cancer science   99(4) 810-815   Apr 2008   [Refereed]
Sekine E, Okada M, Matsufuji N, Yu D, Furusawa Y, Okayasu R
Mutation research   652(1) 95-101   Mar 2008   [Refereed]
Moeller R, Setlow P, Horneck G, Berger T, Reitz G, Rettberg P, Doherty AJ, Okayasu R, Nicholson WL
Journal of bacteriology   190(3) 1134-1140   Feb 2008   [Refereed]
Cui X, Kobayashi Y, Akashi M, Okayasu R
Current medicinal chemistry   15(22) 2293-2304   2008   [Refereed]
Kato T, Nagasawa H, Warner C, Okayasu R, Bedford JS
International journal of radiation biology   83(9) 583-591   Sep 2007   [Refereed]
Niina I, Uchiumi T, Izumi H, Torigoe T, Wakasugi T, Igarashi T, Miyamoto N, Onitsuka T, Shiota M, Okayasu R, Chijiiwa K, Kohno K
Cancer science   98(6) 858-863   Jun 2007   [Refereed]
Okada M, Okabe A, Uchihori Y, Kitamura H, Sekine E, Ebisawa S, Suzuki M, Okayasu R
British journal of cancer   96(11) 1707-1710   Jun 2007   [Refereed]
Fürweger C, Hajek M, Vana N, Kodym R, Okayasu R
Radiation protection dosimetry   126(1-4) 418-422   2007   [Refereed]
The PCC assay can be used to predict radiosensitivity in biopsy cultures irradiated with different types of radiation.
Suzuki M, Tsuruoka C, Nakano T, Ohno T, Furusawa Y, Okayasu R
Oncology reports   16(6) 1293-1299   Dec 2006   [Refereed]
Noguchi M, Yu D, Hirayama R, Ninomiya Y, Sekine E, Kubota N, Ando K, Okayasu R
Biochemical and biophysical research communications   351(3) 658-663   Dec 2006   [Refereed]
Okayasu R, Okada M, Okabe A, Noguchi M, Takakura K, Takahashi S
Radiation research   165(1) 59-67   Jan 2006   [Refereed]
Takakura K, Yaguchi S, Kanansugi Y, Kobayashi K, Okayasu R, Fujibayashi Y
Radiation protection dosimetry   122(1-4) 188-194   2006   [Refereed]
Fujimori A, Okayasu R, Ishihara H, Yoshida S, Eguchi-Kasai K, Nojima K, Ebisawa S, Takahashi S
Cancer research   65(22) 10159-10163   Nov 2005   [Refereed]
Kawata T, Ito H, Saito M, Uno T, Okayasu R, Liu C, Kan'o M, George K, Cucinotta FA
Radiation research   164(4 Pt 2) 509-513   Oct 2005   [Refereed]
Wate R, Takahashi S, Ito H, Kusaka H, Kubota Y, Suetomi K, Sato H, Okayasu R
Journal of radiation research   46(1) 67-73   Mar 2005   [Refereed]
Okayasu R, Takakura K, Poole S, Bedford JS
Journal of radiation research   44 329-333   Dec 2003   [Refereed]
Okayasu R, Takahashi S, Sato H, Kubota Y, Scolavino S, Bedford JS
DNA repair   2(3) 309-314   Mar 2003   [Refereed]
Takahashi S, Sato H, Kubota Y, Utsumi H, Bedford JS, Okayasu R
Toxicology   180(3) 249-256   Dec 2002   [Refereed]
Silencing expression of the catalytic subunit of DNA-dependent protein kinase by small interfering RNA sensitizes human cells for radiation-induced chromosome damage, cell killing, and mutation.
Peng Y, Zhang Q, Nagasawa H, Okayasu R, Liber HL, Bedford JS
Cancer research   62(22) 6400-6404   Nov 2002   [Refereed]
Elevated breast cancer risk in irradiated BALB/c mice associates with unique functional polymorphism of the Prkdc (DNA-dependent protein kinase catalytic subunit) gene.
Yu Y, Okayasu R, Weil MM, Silver A, McCarthy M, Zabriskie R, Long S, Cox R, Ullrich RL
Cancer research   61(5) 1820-1824   Mar 2001   [Refereed]
Further evidence that the survival of irradiated mammalian cells is controlled by temporal processes.
Lett JT, Bergtold DS, Cox AB, Keng PC, Okayasu R
The British journal of cancer. Supplement   6 163-168   1984   [Refereed]
Takahashi S, Takeda E, Kubota Y, Okayasu R
Radiation research   154(6) 686-691   Dec 2000   [Refereed]
A deficiency in DNA repair and DNA-PKcs expression in the radiosensitive BALB/c mouse.
Okayasu R, Suetomi K, Yu Y, Silver A, Bedford JS, Cox R, Ullrich RL
Cancer research   60(16) 4342-4345   Aug 2000   [Refereed]
Okayasu R, Wu L, Hei TK
British journal of cancer   79(9-10) 1319-1324   Mar 1999   [Refereed]
Asbestos and DNA double strand breaks.
Okayasu R, Takahashi S, Yamada S, Hei TK, Ullrich RL
Cancer research   59(2) 298-300   Jan 1999   [Refereed]
Kubota N, Ozawa F, Okada S, Inada T, Komatsu K, Okayasu R
Cancer letters   133(2) 161-167   Nov 1998   [Refereed]
Okayasu R, Suetomi K, Ullrich RL
Radiation research   149(5) 440-445   May 1998   [Refereed]
Yamada S, Yang TC, George K, Okayasu R, Ando K, Tsujii H
Advances in space research : the official journal of the Committee on Space Research (COSPAR)   22(12) 1709-1717   1998   [Refereed]
Cheong N, Okayasu R, Shah S, Ganguly T, Mammen P, Iliakis G
International journal of radiation biology   69(6) 665-677   Jun 1996   [Refereed]
Defective repair of DNA double-strand breaks and chromosome damage in fibroblasts from a radiosensitive leukemia patient.
Badie C, Iliakis G, Foray N, Alsbeih G, Pantellias GE, Okayasu R, Cheong N, Russell NS, Begg AC, Arlett CF
Cancer research   55(6) 1232-1234   Mar 1995   [Refereed]
Kinashi Y, Okayasu R, Iliakis GE, Nagasawa H, Little JB
Radiation research   141(2) 153-159   Feb 1995   [Refereed]
Okayasu R, Cheong N, Iliakis G
International journal of radiation biology   64(6) 689-694   Dec 1993   [Refereed]
Mitosis-promoting factor activity of inducer mitotic cells may affect radiation yield of interphase chromosome breaks in the premature chromosome condensation assay.
Cheng X, Pantelias GE, Okayasu R, Cheong N, Iliakis G
Cancer research   53(23) 5592-5596   Dec 1993   [Refereed]
Ionizing radiation induces two forms of interphase chromosome breaks in Chinese hamster ovary cells that rejoin with different kinetics and show different sensitivity to treatment in hypertonic medium or beta-araA.
Okayasu R, Iliakis G
Radiation research   136(2) 262-270   Nov 1993   [Refereed]
Increased frequency of formation of interphase ring-chromosomes in radiosensitive irs-1 cells exposed to X-rays.
Okayasu R, Pantelias GE, Iliakis G
Mutation research   294(3) 199-206   Oct 1993   [Refereed]
Hypertonic treatment during premature chromosome condensation allows visualization of interphase chromosome breaks repaired with fast kinetics in irradiated CHO cells.
Iliakis G, Okayasu R, Varlotto J, Shernoff C, Wang Y
Radiation research   135(2) 160-170   Aug 1993   [Refereed]
Hypertonic treatment does not affect the radiation yield of interphase chromosome breaks in DNA double-strand break repair-deficient xrs-5 cells.
Okayasu R, Varlotto J, Iliakis G
Radiation research   135(2) 171-177   Aug 1993   [Refereed]
Iliakis GE, Pantelias GE, Okayasu R, Blakely WF
Radiation research   131(2) 192-203   Aug 1992   [Refereed]
Okayasu R, Iliakis G
International journal of radiation biology   61(4) 455-463   Apr 1992   [Refereed]
Effects of hyperthermia on the repair of radiation-induced DNA single- and double-strand breaks in DNA double-strand break repair-deficient and repair-proficient cell lines.
Iliakis G, Seaner R, Okayasu R
International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group   6(4) 813-833   Jul 1990   [Refereed]
Iliakis GE, Okayasu R
International journal of radiation biology   57(6) 1195-1211   Jun 1990   [Refereed]
Iliakis G, Kurtzman S, Pantelias G, Okayasu R
Radiation research   119(2) 286-304   Aug 1989   [Refereed]

Misc

 
Lett, J. T., Bergtold, D.S., Cox, A.B., and Okayasu, R. Further evidence that the survival of irradiated mammalian cells is controlled by temporal processes.
Brit. J. Cancer   49(Suppl. VI), 163-168    1984
Okayasu, R. The DNA repair processes of radiosensitive L5178Y S/S cells and their significance in radiobiology.
Radiation Biology Research Communication, in Japanese.   22, 229-242    1987
Iliakis, G., Pantelias, G.E., Okayasu, R., and Seaner, R. 125IdUrd-induced chromosome fragment, assayed by premature chromosome condensation, and DNA double strand breaks have similar repair kinetics in G1-phase CHO-cells.
Int. J. Radiat. Biol.   52, 705-722    1987
Iliakis, G., and Okayasu, R. The level of induced DNA double strand breaks does not correlate with cell killing in X-irradiated mitotic and G1-phase CHO cells.
Int. J. Radiat. Biol.   53, 395-404    1988
Okayasu, R., Bloecher, D., and Iliakis, G. Variation through the cell cycle of DNA elution dose response in X-irradiation synchronous CHO cells.
Int. J. Radiat. Biol.   53, 729-747    1988
Iliakis, G., Pantelias, G., Okayasu, R., and Seaner, R. Comparative studies on repair inhibition by ara A, ara C, and aphidicolin of radiation induced DNA and chromosome damage in rodent cells: comparison with fixation of PLD.
Int. J. Radiat. Oncol. Biol. Phys.   16, 1261-1265    1989
Okayasu, R. Is induction of DNA double stand breaks different in S-phase cells?
Radiation Biology Research Communication, in Japanese.   24, 53-58    1989
Iliakis, G., Kurtzman, S., Pantelias, G., and Okayasu, R. Mechanism of radiosensitization of pyrimidines: Effect of BrdUrd on radiation induction of DNA and chromosome damage and its correlation with cell killing.
Radiat. Res.   119, 286-304    1989
Iliakis, G., Seaner, R., and Okayasu, R. Effects of hyperthermia on the repair of radiation-induced DNA single and double strand breaks in DNA double strand break repair deficient and repair proficient cell lines.
Int. J. Hyperthermia   6, 813-833    1990
Iliakis, G.E., and Okayasu, R. Radiosensitivity throughout the cell cycle, and repair of potential lethal damage and DNA double strand breaks in an X-ray sensitive CHO mutant.
Int. J. Radiat. Biol.   57, 1195-1211    1990
Okayasu, R., and Iliakis, G. The shape of DNA elution dose response curves under non-denaturing conditions in Chinese Hamster cells: The importance of the degree of chromatin condensation.
Int. J. Radiat. Biol.   61, 455-463    1992
Iliakis, G.E., Pantelias, G.E., Okayasu, R., and Blakely, F.B. Induction by H202 of DNA and interphase-chromosome damage in plateau-phase CHO cells.
Radiat. Res.   131, 192-203    1992
Iliakis, G., Okayasu, R., Varlotto, J. Shernoff, C., and Wang, Y. Hypertonic treatment during premature chromosome condensation allows visualization of a class of interphase chromosome breaks repaired with fast kinetics in irradiated CHO cells.
Radiat. Res.   135, 160-170    1993
Okayasu, R., Varlotto, J., and Iliakis, G. Hypertonic treatment does not affect the radiation yield of interphase chromosome breaks in DNA double strand break repair deficient xrs-5 cells.
Radiat. Res.   135, 171-177    1993
Okayasu, R., Pantelias, G.E. and Iliakis, G. Increased frequency of formation of interphase ring-chromosome in radiation sensitive irs-1 cells exposed to x-rays.
Mutat. Res.   294, 199-206    1993
Cheng, X, Pantelias, G.E., Okayasu, R., Cheong, N., and Iliakis, G. Mitosispromoting factor activity of inducer mitotic cells may affect the radiation yield of interphase chromosome breaks measured in the premature chromosome condensation assay.
Cancer Res.   53, 5592-5596    1993
Okayasu, R., and Iliakis, G. Ionizing radiation induces two forms of interphase chromosome breaks in CHO cells that rejoin with different kinetics and show different sensitivity to treatment in hypertonic medium or ara
A. Radiat. Res.   136, 262-270    1993
Okayasu, R. and Iliakis, G. Evidence that the product of the xrs-5 gene is predominantly involved in the repair of a subset of radiation-induced interphase chromosome breaks rejoining with fast kinetics.
Radiat. Res.   138, 34-43    1994
Okayasu, R., and Iliakis, G. Mitotic metaphase cells from different cell lines cause different levels of expression of the a-form of interphase chromosome breaks in irradiated CHO cells.
Mutat. Res.   310, 65-71    1994
Okayasu, R. Radiation sensitivity and cell cycle control.
Medical Immunology   28, 325-331    1994
Kinashi, Y., Okayasu, R., Iliakis, G.E., Nagasawa, H., and Little, J. Pulse field gel electrophoresis measurement of DNA double strand breaks caused by restriction endonucleases in x-ray-sensitive CHO mutant cells (xrs-5)
Radiat. Res.   141, 153-159    1995
Badie, C., Iliakis, G., Foray, N., Alsbeih, G., Pantelias, G.E., Okayasu, R., Cheong, N., Russell, N.S., Begg, A.C., Arlett, C., and Malaise, E.P. Defective repair of DNA double strand breaks and chromosome breaks in fibroblasts from a radiosensitive ・・・
Cancer Res.   55, 1232-1234    1995
Badie, C., Iliakis, G., Foray, N., Alsbeih, G., Pantelias, G.E., Okayasu, R., Cheong, N., Russell, N.S., Begg, A.C., Arlett, C., and Malaise, E.P. Defective repair of DNA double strand breaks and chromosome breaks in fibroblasts from a radiosensi...
Cheong, N., Okayasu, R., Shah, S., Mamen, P., Ganguly, T., and Iliakis, G. In vitro rejoining of double strand breaks in cellular DNA by factors present in the cytoplasmic extract from HeLe cells.
Intl. J. Rad. Biol.   69, 665-677    1996
Okayasu, R. Suetomi, K. and Ullrich, R.L. Wortmannin inhibits repair of DNA double strand breaks in irradiated normal human cells.
Radiat. Res.   149, 440-445    1998
Kubota, N., Ozawa, F., Inada, T., Komatsu, K and, Okayasu, R. The phospatidylinositol 3-kinase inhibitor wortmannin sensitizes quiescent human tumor cells but not proliferating MG-63 cells to radiation.
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Okayasu, R., Takahashi, S., Yamada, S., Hei, T. and Ullrich R. L. Asbestos and DNA double strand breaks.
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Okayasu, R., Wu, L., and Hei, T.K. Biological effects of naturally occurring and man-made fibers: in vitro cytotoxicity and mutagenesis in mammalian cells.
British J. Cancer   79, 1319-1324    1999
Yamada, S., Yang, T.C., George, K., Okayasu, R., Ando, K. and Tsujii, H. Microsatellite instability in human mammary epithelial cells transformed by heavy ions.
Adv. Space Res.   22 (12), 1709-1717    1999
Takahashi, S., Takeda, E., Kubota, Y. and Okayasu, R. Inhibition of radiation induced DNA-double strand break repair by nickel and arsenite.
Radiat. Res.   154, 686-691    2000
Okayasu, R., Suetomi, K., Yu, Y., Bedford, J.S., Cox, R. and Ullrich, R.L. A deficiency in DNA repair and DNA-PKcs expression in the radiosensitive BALB/c mice.
Cancer Res.   60, 4342-4345    2000
Yu, Y., Okayasu, R., Weil, M.W., Silver, A., McCarthy, M., Zabriskie, R., Long, S., Cox, R. and Ullrich, R.L. Elevated breast cancer risk in irradiated BALB/c mice associates with unique functional polymorphism of the Prkdc (DNA PKcs)
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Peng,Y,Zhang, Q., Nagasawa, H., Okayasu, R., Liber, H.L. and Bedford, J. S. DNA-Pkcs silencing by siRNA sensitizes human cells for radiation-induced chromosome damage, cell killing and mutation.
Cancer Res.   62, 6400-6404    2002
Takahashi, S., Sato, S., Kubota, Y., Utsumi, H., Bedford, J.S. and Okayasu, R. Inhibition of DNA-double strand break repair by antimony compounds.
Toxicology   180, 249-256    2002
Okayasu, R., Takahashi, S., Sato, H., Kubota, Y., Scolavino, S. and Bedford, J.S. Induction of DNA double strand breaks by arsenite: comparative studies with DNA breaks induced by X-rays.
DNA Repair    2, 309-314    2003
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Iliakis, G., Metzger, L., Okayasu, R., Pantelias, G., and Cicilioni, O. Measurement of DNA double strand breaks in mammalian cells: Comparison between pulsed field gel electrophoresis and ono-unwinding filter elution.
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Battele Press   427-440    1995
Takahashi, S., Kubota, Y., Sato, H., Furuya, K. and Okayasu, R. Comparison of toxic effects of radiation and environmental pollutants in assay systems using a transgenic mouse, cultured alveolar macrophages, and DNA double strand break analyses. Compar・・・
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Takahashi, S., Kubota, Y., Sato, H., Furuya, K. and Okayasu, R. Comparison of toxic effects of radiation and environmental pollutants in assay systems using a transgenic mouse, cultured alveolar macrophages, and DNA double strand break analyses. C...
Takahashi, S., Okayasu, R. Sato, H, Kubota, Y and Bedford, J.S. Inhibition of radiation induced DNA-double strand break repair by various metal/metalloid compounds.
Proceedings for International Symposium of Radiation Homeostasis, Kyoto, Japan 7/13-7/16      2001
Iimuro, R, Takahashi, S, Ito, H, Kubota, Y, Suetomi, K, Sato, H, Okayasu, R. Radio-sensitivity of the cells from amyotrophic lateral sclerosis model mice transfected with human mutant SOD1
J. Radiat. Res.   46, 67-73    2005
Kawata, T., Ito, H., Saito, M., Uno, T., Okayasu, R., Liu, C., Kan’o, M., George, K. And Cucinotta, F.A. Caffeine sensitizes non-dividing human fibroblasts to X-rays by inducing high frequency of misrepair.
Radiat. Res.   164, 509-513    2005
Fujimori, A., Okayasu, R., Ishihara, H., Yoshida, S., Eguchi-Kasai, K., Nojima, K., Ebisawa, S., Takahashi, S.Extremely low-dose ionizing radiation upregulates CXC chemokines in normal human fibroblasts.
Cancer Res.   65, 10159-10163    2005
Okayasu, R., Okada, M, Okabe, A., Noguchi, M., Takakura, K. and Takahashi, S. Heavy ion radiation induces complex DNA damage that cannot be efficiently repaired by non-homologous end joining.
Radiat. Res.      2005
Okayasu, R., Suetomi, K., and Takahashi, S. Suppression of DNA double strand break repair by RNAi technology: An application to radiation therapy?
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Works

 
DNA Double Strard Break Repair in Tobacco Carcinogenesis
2002 - 2004