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Journal Articles

Real-time observation of irradiated HeLa-cell modified by fluorescent ubiquitination-based cell-cycle indicator using synchrotron X-ray microbeam

Narita, Ayumi; Kaminaga, Kiichi; Yokoya, Akinari; Noguchi, Miho; Kobayashi, Katsumi*; Usami, Noriko*; Fujii, Kentaro

Radiation Protection Dosimetry, 166(1-4), p.192 - 196, 2015/09

 Times Cited Count:2 Percentile:73.66(Environmental Sciences)

For the knowledge about irradiation effects of mammalian cells depending on the cell cycle, most of them had been analyzed by statistical approches. Our purpose is to establish the method for real-time observation of irradiated cells under a microscope. Fluorescent ubiquitination-based cell cycle indicator (FUCCI) human cancer (HeLa) cells (red indicates G1; green, S/G2) were exposed to a synchrotron X-ray microbeam. Cells in either G1 or S/G2 were selectively irradiated according to cell color observed in the same microscopic field in a culture dish. Time-lapse micrographs of the irradiated cells were acquired for 24 h after irradiation. The cell cycle was strongly arrested by irradiation at S/G2 and never progressed to G1. In contrast, cells irradiated at G1 progress to S/G2 with a similar time course as non-irradiated control cells. These results show single FUCCI cell exposure and live cell imaging are powerful methods for studying radiation effects on the cell cycle.

Journal Articles

Genetic changes in progeny of bystander human fibroblasts after microbeam irradiation with X-rays, protons or carbon ions; The Relevance to cancer risk

Autsavapromporn, N.*; Plante, I.*; Liu, C.*; Konishi, Teruaki*; Usami, Noriko*; Funayama, Tomoo; Azzam, E.*; Murakami, Takeshi*; Suzuki, Masao*

International Journal of Radiation Biology, 91(1), p.62 - 70, 2015/01

 Times Cited Count:19 Percentile:6.33(Biology)

Radiation-induced bystander effects have important implications in radiotherapy. Their persistence in normal cells may contribute to risk of health hazards, including cancer. This study investigates the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of harmful effects in progeny of bystander cells. Confluent human skin fibroblasts were exposed to microbeam radiations with different linear energy transfer (LET) by which 0.036$$sim$$0.4% of the cells were directly targeted by radiation. Following 20 population doublings, the cells were harvested and assayed for micronucleus formation, gene mutation and protein oxidation. The results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET.

Journal Articles

Radiation-quality-dependent bystander effects induced by the microbeams with different radiation sources

Suzuki, Masao*; Autsavapromporn, N.*; Usami, Noriko*; Funayama, Tomoo; Plante, I.*; Yokota, Yuichiro; Muto, Yasuko*; Suzuki, Michiyo; Ikeda, Hiroko; Hattori, Yuya; et al.

Journal of Radiation Research, 55(Suppl_1), P. i54, 2014/03

Journal Articles

Gap junction communication and the propagation of bystander effects induced by microbeam irradiation in human fibroblast cultures; The Impact of radiation quality

Autsavapromporn, N.*; Suzuki, Masao*; Funayama, Tomoo; Usami, Noriko*; Plante, I.*; Yokota, Yuichiro; Muto, Yasuko*; Ikeda, Hiroko; Kobayashi, Katsumi*; Kobayashi, Yasuhiko; et al.

Radiation Research, 180(4), p.367 - 375, 2013/10

 Times Cited Count:46 Percentile:8.76(Biology)

We investigated the role of gapjunction intercellular communication (GJIC) in the propagation of stressful effects in confluent normal human fibroblast cultures wherein only 0.036-0.144% of cells in the population were traversed by primary radiation tracks. Confluent cells were exposed to graded doses from X ray, carbon ion, neon ion or argon ion microbeams in the presence or absence of an inhibitor of GJIC. After 4 h incubation, the cells were assayed for micronucleus (MN) formation. Micronuclei were induced in a greater fraction of cells than expected based on the fraction of cells targeted by primary radiation, and the effect occurred in a dose-dependent manner with any of the radiation sources. Interestingly, the inhibition of GJIC depressed the enhancement of MN formation in bystander cells from cultures exposed to high-LET radiation but not low-LET radiation. The results highlight the important role of radiation quality and dose in the observed effects.

Journal Articles

Microbeam irradiation facilities for radiobiology in Japan and China

Kobayashi, Yasuhiko; Funayama, Tomoo; Hamada, Nobuyuki*; Sakashita, Tetsuya; Konishi, Teruaki*; Imaseki, Hitoshi*; Yasuda, Keisuke*; Hatashita, Masanori*; Takagi, Keiichi*; Hatori, Satoshi*; et al.

Journal of Radiation Research, 50(Suppl.A), p.A29 - A47, 2009/03

 Times Cited Count:32 Percentile:27.02(Biology)

Journal Articles

Reparability of lethal lesions produced by phosphorus photoabsorption in yeast cells

Usami, Noriko*; Yokoya, Akinari; Ishizaka, Shozo*; Kobayashi, Katsumi*

Journal of Radiation Research, 42(3), p.317 - 331, 2001/09

 Times Cited Count:7 Percentile:72.56(Biology)

The characteristics of DNA lesions produced by the phosphorus K-shell absorption in yeast cells were studied using monochromatized soft X-rays tuned to the phosphorus K-edge peak (2153 eV) and below the peak energy (2147 eV). The repaired fractions of DNA double-strand breaks (dsb) were measured relatively by using both a mutant, (${it rad 54-3}$), which shows the temperature-sensitive dsb repair-deficient, and a wild-type strain. The repaired fraction of lesion in ${it rad 54-3}$, which corresponds to the relative yield of dsb reparable by the ${it RAD 54}$ pathway, was not affected by the phosphorus photoabsorption. Repair of the produced lesions in the wild-type cells was also measured by comparing the surviving fraction of the immediately plated cells to that of those cells plated after holding in a non-nutrient medium for 80 hrs. The recovery of the surviving fraction after the holding treatment was dependent upon the soft X-ray energy. These results suggest that irrepairable lesions are produced by the inner-shell photoabsorption of phosphorus in DNA, although its yield is small.

Journal Articles

Lethal effect of K-shell absorption of intracellular phosphorus on wild-type and radiation sensitive mutants of Escherichia coli

Maezawa, Hiroshi*; Furusawa, Yoshiya*; Kobayashi, Katsumi*; Hieda, Kotaro*; Suzuki, Masao*; Usami, Noriko*; Yokoya, Akinari; Mori, Tomoyuki*

Acta Oncologica, 35(7), p.889 - 894, 1997/01

 Times Cited Count:6 Percentile:79.09(Oncology)

no abstracts in English

Journal Articles

XAFS studies of uranium(VI) and thorium(IV)-amide and TBP complexes in ethanol solution

Yaita, Tsuyoshi; Narita, Hirokazu*; Suzuki, Shinichi; Shiwaku, Hideaki; Motohashi, Haruhiko; Ono, Hideo; Usami, Noriko*; Kobayashi, Katsumi*

Photon Factory Activity Report 1997, P. 81, 1997/00

no abstracts in English

Journal Articles

Single- and double-strand breaks in pBR322 plasmid DNA by monochromatic X-rays on and off the K-absorption peak of phosphorus

Hieda, Kotaro*; Hirono, Taisuki*; Azami, Akira*; Suzuki, Masao*; *; Maesawa, Hiroshi*; Usami, Noriko*; Yokoya, Akinari; Kobayashi, Katsumi*

International Journal of Radiation Biology, 70(4), p.437 - 445, 1996/10

 Times Cited Count:46 Percentile:4.18(Biology)

no abstracts in English

Journal Articles

Synchrotron radiation beamline to study radioactive materials at the Photon Factory

Konishi, Hiroyuki; Yokoya, Akinari; Shiwaku, Hideaki; Motohashi, Haruhiko; *; Kashihara, Yasuharu*; *; Harami, Taikan; Sasaki, Teikichi; Maeta, Hiroshi; et al.

Nuclear Instruments and Methods in Physics Research A, 372, p.322 - 332, 1996/00

 Times Cited Count:47 Percentile:4.18(Instruments & Instrumentation)

no abstracts in English

Journal Articles

Performance of the irradiation apparatus for radiation biology studies at beamline 27 in the photon factory

Kobayashi, Katsumi*; Usami, Noriko*; Yokoya, Akinari

Journal of Radiation Research, 34(1), 110 Pages, 1993/03

no abstracts in English

Journal Articles

Inactivation action spectra of bacillus subtilis spores with monochromatic soft X-rays(0.1-0.6nm) of synchrotron radiation

*; Hieda, Kotaro*; Usami, Noriko*; Yokoya, Akinari; Kobayashi, Katsumi*

Radiat. Res., 131(1), p.72 - 80, 1992/07

 Times Cited Count:15 Percentile:42.19(Biology)

no abstracts in English

Journal Articles

Characteristics of degradation of amino acid with site-specific inner-shell photoionization

Yokoya, Akinari; Usami, Noriko*; Kobayashi, Katsumi*

Photon Factory News, 10(1), p.13 - 14, 1992/05

no abstracts in English

Journal Articles

Degradation of amino acids irradiated with vacuum-UV radiation(60nm, 120nm)

Yokoya, Akinari; Kobayashi, Katsumi*; Usami, Noriko*; *; Hieda, Kotaro*; *

Shinku Shigaisen (50nm Ijo) Niyoru Kakusan Sonsho Yuhatsu Kiko No Sogoteki Kenkyu, p.56 - 59, 1992/03

no abstracts in English

Journal Articles

Molecular change of a sulfur-containing amino acid in aqueous solution with monochromatized soft X-ray irradiation

Yokoya, Akinari; Kobayashi, Katsumi*; Usami, Noriko*

Photon Factory Activity Report, P. 299, 1992/00

no abstracts in English

Oral presentation

Radiation-quality-dependence in bystander cellular effects on normal human cells induced by carbon-ion and X-ray microbeams

Suzuki, Masao*; Furusawa, Yoshiya*; Tsuruoka, Chizuru*; Kobayashi, Katsumi*; Usami, Noriko*; Maeda, Munetoshi*; Funayama, Tomoo; Sakashita, Tetsuya; Yokota, Yuichiro; Fukamoto, Kana; et al.

no journal, , 

no abstracts in English

Oral presentation

Facility of radioactive materials beamline at KEK

Hirao, Norie; Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Okamoto, Yoshihiro; Suzuki, Shinichi; Yaita, Tsuyoshi; Usami, Noriko*; Kobayashi, Katsumi*

no journal, , 

We report here the facility of radioactive materials beamline at KEK (High Energy Accelerator Research Organization). The beamline was designed and built by Japan Atomic Energy Agency (JAEA). The experimental stations of BL-27 are located inside the "hot" laboratory where radioactive materials or samples including U or Th can be handled, in order to irradiate these samples with synchrotron X-rays. The beamline is divided into two branch lines; one is BL-27A for soft X-rays (1.8 to 6 keV) and the other is BL-27B for X-rays (4 to 20 keV). In BL-27A, irradiation apparatuses for radiobiology, photoelectron spectrometer (XPS) and photoelectron emission microscopy (PEEM) are installed in tandem. In BL-27B, irradiation apparatuses for radiobiology and XAFS spectrometer are inside hatch. This beamline is equipped with XAFS experiments (transmission XAFS, fluorescent XAFS and Imaging XAFS).

Oral presentation

DNA base lesions induced by phorosphorus K-ionization and its Auger decay

Yokoya, Akinari; Usami, Noriko*; Maeda, Munetoshi*

no journal, , 

In previous studies, DNA double strand breaks (DSBs) induced by phosphorus K-shell ionization are studied in terms of its cell killing effect. Recently non-DSB type complex damage has been known to induce radiobiological effect such as mutation. The complex damage consists of several base lesions produced in a few nm of DNA molecule, and retard the enzymatic repair process. However there was very little knowledge about the base lesions induced by phosphorus K-shell ionization. In this study, experimental evidences of the production of the base lesions are reported using plasmid DNA as a model molecule. The yields of the base lesions were quantified using base excision repair proteins as enzymatic probes (glycosylases). Several irradiation conditions were tested and the obtained results are compared to discuss the process of the base lesions formation.

Oral presentation

New approach for study cell cycle modification of HeLa cells by irradiation usimg synchrotron X-ray microbeam

Narita, Ayumi; Kaminaga, Kiichi; Noguchi, Miho; Yokoya, Akinari; Kobayashi, Katsumi*; Usami, Noriko*; Fujii, Kentaro

no journal, , 

no abstracts in English

Oral presentation

Effect of X-irradiation to Fucci cells on cell cycle observed by time-lapse imaging technique

Kaminaga, Kiichi; Narita, Ayumi; Noguchi, Miho; Kobayashi, Katsumi*; Usami, Noriko*; Yokoya, Akinari

no journal, , 

no abstracts in English

34 (Records 1-20 displayed on this page)