A5003253202- Radiation Therapy and Dosimetry
- Effects of Radiation Exposure
- Plant Genetic and Mutation Studies
- DNA Repair Mechanisms
- Radiation Effects and Dosimetry
- Carcinogens and Genotoxicity Assessment
- Spaceflight effects on biology
- Cell death mechanisms and regulation
- Glioma Diagnosis and Treatment
- Birth, Development, and Health
- Radiation Effects in Electronics
- Biofield Effects and Biophysics
- Heat shock proteins research
- Immune Cell Function and Interaction
- Graphite, nuclear technology, radiation studies
- Wireless Body Area Networks
- Bacillus and Francisella bacterial research
- Advanced Radiotherapy Techniques
- Childhood Cancer Survivors' Quality of Life
- Radiation Dose and Imaging
- Cancer Immunotherapy and Biomarkers
- Cancer Research and Treatments
- Particle accelerators and beam dynamics
- Phagocytosis and Immune Regulation
- Brain Metastases and Treatment
National Institutes for Quantum Science and Technology
2016-2024
National Institute of Health Sciences
2014
Research Institute of Radio
2006-2009
International Space Station
2003-2004
Tsuruoka, C., Suzuki, M., Kanai, T. and Fujitaka, K. LET Ion Species Dependence for Cell Killing in Normal Human Skin Fibroblasts. Radiat. Res. 163, 494–500 (2005).We studied the ion species dependence of RBE cell killing to clarify differences biological effects caused by track structure that result from different energy depositions ions. human skin fibroblasts were irradiated with heavy-ion beams such as carbon, neon, silicon iron ions generated Heavy Medical Accelerator Chiba (HIMAC) at...
It is considered that the linear energy transfer (LET) may not be ideal index for expressing relative biological effectiveness (RBE) of cell killing heavy-ion irradiation, as ion-species dependencies have clearly been observed in relation between LET and RBE derived from cell-survival fraction data. The previously measured survival fractions four lines irradiated by various ion species, employing saturation-corrected dose-mean lineal energy, y*, instead were therefore re-analysed. In...
We measured the yield and spectrum of strand breaks nucleobase lesions produced in fully hydrated plasmid DNA films to determine linear energy transfer (LET) dependence damage induced by ion-beam irradiation relation change atomic number ions. The isolated was revealed as a decrease prompt SSBs with increasing LET He2 , C5 ,6 Ne8 ,10 On other hand, yields DSBs increased ion LET. were additionally ion-irradiated film treatment two kinds base excision repair proteins (glycosylases), Nth Fpg,...
We studied the LET and ion species dependence of induction chromatin breaks measured immediately after irradiation as initially 24 h postirradiation incubation (37 degrees C) non-rejoined in normal human fibroblasts with different heavy ions, such carbon, neon, silicon iron, generated by Heavy Ion Medical Accelerator Chiba (HIMAC) at National Institute Radiological Science (NIRS). Chromatin were an excess number fragments prematurely condensed chromosomes using premature chromosome...
Recently reported studies have led to a heightened awareness of the risks cancer induced by diagnostic radiological imaging, and in particular, risk brain after childhood CT scans. One feature Ptch1 /– mice is their sensitivity radiation-induced medulloblastomas (an embryonic cerebellar tumor) during narrow window time centered on days around birth. Little known about dynamics how dose protraction interacts with such windows individual tissues. Using from irradiated hybrid C3H × C57BL/6 F1...
Recent studies have identified interstitial deletions in the cancer genome as a radiation-related mutational signature, although most of them do not fall on driver genes. Pioneering field indicated presence loss heterozygosity (LOH) spanning Apc subset sporadic and radiation-induced intestinal tumors ApcMin/+ mice, albeit with substantial which LOH was detected; whether copy number losses accompany such has also been unclear. Herein, we analyzed C3B6F1 mice that were either left untreated or...
Monitoring mice exposed to carbon ion radiotherapy provides an indirect method evaluate the potential for second cancer induction in normal tissues outside target volume, since such estimates are not yet possible from historical patient data. Here, male and female B6C3F1 were given single or fractionated whole-body exposure(s) a monoenergetic beam at Heavy Ion Medical Accelerator Chiba, Japan, matching radiation quality delivered tissue ahead of tumour volume (average linear energy transfer...
We investigated the relative biological effectiveness (RBE) of therapeutic proton beams at six facilities in Japan with respect to cell lethality HSG cells. The RBE treatments could be determined from experimental data. For this purpose, we used a survival assay compare cell-killing efficiency beams. Among five linear accelerator (LINAC) X-ray machines 4 or 6 MeV that were as reference beams, there was only small variation (coefficient CV = 3.1% D10) effectiveness. averaged value D10 for...
Ionizing radiation can damage DNA and, therefore, is a risk factor for cancer. Eker rats, which carry heterozygous germline mutation in the tumor-suppressor gene tuberous sclerosis complex 2 (Tsc2), are susceptible to radiation-induced renal carcinogenesis. However, molecular mechanisms involved Tsc2 inactivation unclear. We subjected Fischer 344 × (Long Evans
We investigated the difference in cell-killing effect and mutation induction between carbon- neon-ion beams normal human cells. Carbon- were accelerated by Riken Ring Cyclotron (RRC) at Institute of Physical Chemical Research Japan. Cell-killing was measured as reproductive cell death using colony formation assay. Mutation HPRT locus detected to measure 6-thioguanine-resistant clones. The spectrum deletion pattern exons induced mutants analyzed multiplex polymerase chain reaction (PCR)....
There is a natural tendency to expect that irradiation of an infant organ prior development-related expansion will result in higher risk developing cancer than fully-developed adult tissue, and this has generally been observed. However, if tissues also vary their initial responses radiation depending on age, the interplay between tissue- age-dependent would potentially be quite complex. We have previously shown opposing induction apoptosis for intestinal epithelium hematopoietic cells mice,...
The intergenerational effects from chronic low-dose exposure are matters of concern. It is thus important to elucidate the radiation-induced germ cell maturation, fertilization and embryonic development. well known that DNA methylation levels in CpG sites gametes reprogrammed stages during their maturity. Furthermore, binding Izumo on surface sperm Juno oocytes essential for fertilization. Thus, there a possibility these genes useful indicators evaluate fertility mice after irradiation...
To clarify the biological effects of space environment, especially radiations, a proposal "Rad Gene" was performed as first life science experiment with two human lymphoblastoid cell lines bearing wild-type p53 gene (wtp53) and mutated (mp53) in an International Space Station (ISS) for 133 days. We scheduled four projects: (1) DNA damage induced by radiations including high linear energy transfer (LET) particles detected track γH2AX foci nuclei these frozen cells. (2) examine microgravity on...
Neutron radiation, a high-linear energy transfer has high relative biological effectiveness (RBE) for various end points. The age at exposure is an important modifier of the effects including carcinogenesis, with infants being generally more radiosensitive. Ptch1+/– mice offer unique experimental system assessing radiation carcinogenesis. Spontaneous development medulloblastoma tumors occurs in nonirradiated animals that lose their Ptch1+ allele, most frequently by loss heterozygosity (LOH)...
Suzuki, M., Tsuruoka, C., Uchihori, Y., Ebisawa, S., Yasuda, H. and Fujitaka, K. Reduction in Life Span of Normal Human Fibroblasts Exposed to Very Low-Dose-Rate Charged Particles. Radiat. Res. 164, 505–508 (2005).We studied the effect chronic low-dose irradiation with heavy ions on life span normal human fibroblasts vitro. Cells were cultured a CO2 incubator that was placed room for biological studies Heavy Ion Medical Accelerator Chiba (HIMAC) at National Institute Radiological Sciences...
We investigated the influence of mutation induction on hypoxanthine guanine phosphoribosyltransferase (hprt) locus in normal human fibroblasts irradiated with X rays or accelerated iron ions LET ranging from 200 to 400 keV/μm. The relative biological effectiveness (RBE) frequency per total number surviving cells for comparatively lower values (200 and 260 keV/μm) this study was higher than 1, RBE 300 keV/μm, 350 keV/μm nearly 1. These results indicated that decreased increasing LET, these...
Abstract The risk of cancer due to exposure ionizing radiation is higher in infants than adults. In a previous study, the effect adult-onset calorie restriction (CR) on carcinogenesis mice after early-life X-rays was examined (Shang, Y, Kakinuma, S, Yamauchi, K, et al. Cancer prevention by infant B6C3F1 male mice. Int J Cancer. 2014; 135: 1038-47). results showed that tumor frequency reduced CR group. However, mechanism suppression not yet clear. this we effects radiation-induced mutations...