Carbon-ion beams induce production of an immune mediator protein, high mobility group box 1, at levels comparable with X-ray irradiation
X-ray radiotherapy activates tumor antigen-specific T-cell responses, and increases in the serum levels of high mobility group box 1 (HMGB1) induced by X-ray irradiation play a pivotal role in activating anti-tumor immunity. Here, we examined whether carbon-ion beams, as well as X-rays, can induce HMGB1 release from human cancer cell lines. The study examined five human cancer cell lines: TE2, KYSE70, A549, NCI-H460 and WiDr. The proportion of cells surviving X- or carbon-ion beam irradiation was assessed in a clonogenic assay. The D10, the dose at which 10% of cells survive, was calculated using a linear–quadratic m...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Yoshimoto, Y., Oike, T., Okonogi, N., Suzuki, Y., Ando, K., Sato, H., Noda, S.-e., Isono, M., Mimura, K., Kono, K., Nakano, T. Tags: Biology Source Type: research
Low-dose energetic protons induce adaptive and bystander effects that protect human cells against DNA damage caused by a subsequent exposure to energetic iron ions
During interplanetary missions, astronauts are exposed to mixed types of ionizing radiation. The low ‘flux’ of the high atomic number and high energy (HZE) radiations relative to the higher ‘flux’ of low linear energy transfer (LET) protons makes it highly probable that for any given cell in the body, proton events will precede any HZE event. Whereas progress has been made in our understanding of the biological effects of low-LET protons and high-LET HZE particles, the interplay between the biochemical processes modulated by these radiations is unclear. Here we show that exposure of normal human fib...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Buonanno, M., De Toledo, S. M., Howell, R. W., Azzam, E. I. Tags: Biology Source Type: research
Effect of age on the sensitivity of the rat thyroid gland to ionizing radiation
Exposure to ionizing radiation during childhood is a well-known risk factor for thyroid cancer. Our study evaluated the effect of age on the radiosensitivity of rat thyroid glands. Four-week-old (4W), 7 -week-old (7W), and 8-month-old (8M) male Wistar rats were exposed to 8 Gy of whole-body X-ray irradiation. Thyroids were removed 3–72 h after irradiation, and non-irradiated thyroids served as controls. Ki67-positivity and p53 binding protein 1 (53BP1) focus formation (a DNA damage response) were evaluated via immunohistochemistry. Amounts of proteins involved in DNA damage response (p53, p53 phosphorylated at serine...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Matsuu-Matsuyama, M., Shichijo, K., Okaichi, K., Kurashige, T., Kondo, H., Miura, S., Nakashima, M. Tags: Biology Source Type: research
Characterization of an orthovoltage biological irradiator used for radiobiological research
Orthovoltage irradiators are routinely used to irradiate specimens and small animals in biological research. There are several reports on the characteristics of these units for small field irradiations. However, there is limited knowledge about use of these units for large fields, which are essential for emerging large-field irregular shape irradiations, namely total marrow irradiation used as a conditioning regimen for hematological malignancies. This work describes characterization of a self-contained Orthovoltage biological irradiator for large fields using measurements and Monte Carlo simulations that could be used to ...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Azimi, R., Alaei, P., Spezi, E., Hui, S. K. Tags: Biology Source Type: research
Chronic low-dose {gamma}-irradiation of Drosophila melanogaster larvae induces gene expression changes and enhances locomotive behavior
This study investigates LDR-induced alterations in locomotive behavior and gene expression profiles of Drosophila melanogaster. We measured locomotive behavior using larval pupation height and the rapid iterative negative geotaxis (RING) assay after exposure to 0.1 Gy -radiation (dose rate of 16.7 mGy/h). We also observed chronic LDR effects on development (pupation and eclosion rates) and longevity (life span). To identify chronic LDR effects on gene expression, we performed whole-genome expression analysis using gene-expression microarrays, and confirmed the results using quantitative real-time PCR. The pupation height o...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Kim, C. S., Seong, K. M., Lee, B. S., Lee, I. K., Yang, K. H., Kim, J.-Y., Nam, S. Y. Tags: Biology Source Type: research
The effects of radio-frequency electromagnetic fields on T cell function during development
With the widespread use of radio-frequency devices, it is increasingly important to understand the biological effects of the associated electromagnetic fields. Thus, we investigated the effects of radio-frequency electromagnetic fields (RF-EMF) on T cell responses during development due to the lack of science-based evidence for RF-EMF effects on developmental immune systems. Sprague Dawley (SD) rats were exposed to 2.14-GHz wideband code division multiple-access (W-CDMA) RF signals at a whole-body specific absorption rate (SAR) of 0.2 W/kg. Exposures were performed for a total of 9 weeks spanning in utero development, lact...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Ohtani, S., Ushiyama, A., Maeda, M., Ogasawara, Y., Wang, J., Kunugita, N., Ishii, K. Tags: Biology Source Type: research
AP endonuclease knockdown enhances methyl methanesulfonate hypersensitivity of DNA polymerase {beta} knockout mouse embryonic fibroblasts
In this study, we prepared Apex-knockdown/PolB-knockout MEFs (AKDBKOs) to examine whether BER is related to the apparent resistance of PolBKOs at low MMS concentrations. The viability of PolBKOs immediately after MMS treatment was significantly lower than that of wild-type MEFs, but there was essentially no effect of Apex-knockdown on cell viability in the presence or absence of PolB. In contrast, relative counts of MEFs after repair were decreased by Apex knockdown. Parental PolBKOs showed especially high sensitivity at >1.5 mM MMS, suggesting that PolBKOs have another repair mechanism in addition to PolB-dependent Sn-...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Yamamoto, R., Umetsu, M., Yamamoto, M., Matsuyama, S., Takenaka, S., Ide, H., Kubo, K. Tags: Biology Source Type: research
New model for long-term investigations of cutaneous microcirculatory and inflammatory changes following irradiation
Radiotherapy is used for curative and palliative treatment. However, its negative effect on normal tissue is a limiting factor for the deliverable dose. Microcirculatory breakdown and prolonged inflammation in particular are major features of late side effects. The purpose of this study was to develop a reliable animal model that will allow a long-term in vivo analysis of microcirculation and inflammation following irradiation. A single dose of 90 Gy was delivered to the ears of hairless mice (n = 15). Intravital fluorescent microscopy was used to assess microcirculatory parameters and leukocyte behaviour. Values for the i...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Goertz, O., Poettgen, C., Akbari, A., Kolbenschlag, J., Langer, S., Lehnhardt, M., Stuschke, M., von der Lohe, L. Tags: Biology Source Type: research
Role of isolated and clustered DNA damage and the post-irradiating repair process in the effects of heavy ion beam irradiation
In this study, we analyzed the yield of clustered base damage (comprising multiple base lesions) in cultured cells irradiated with various heavy ion beams, and investigated isolated base damage and the repair process in post-irradiation cultured cells. Chinese hamster ovary (CHO) cells were irradiated by carbon, silicon, argon and iron ion beams with LETs of 13, 55, 90 and 200 keV µm–1, respectively. Agarose gel electrophoresis of the cells with enzymatic treatments indicated that clustered base damage yields decreased as the LET increased. The aldehyde reactive probe procedure showed that isolated base da...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Tokuyama, Y., Furusawa, Y., Ide, H., Yasui, A., Terato, H. Tags: Biology Source Type: research
Generation of peanut mutants by fast neutron irradiation combined with in vitro culture
In this study, we investigated the effects of fast neutron irradiation on somatic embryogenesis combined with plant regeneration in embryonic leaflet culture to develop new peanut (Arachis hypogaea L.) germplasm for breeding. The dry seeds of the elite cultivar Luhua 11 were irradiated with fast neutrons at dosages of 9.7, 14.0 and 18.0 Gy. The embryonic leaflets were separated and incubated in a medium with 10.0-mg/l 2,4-D to induce somatic embryogenesis. Next, they were incubated in a medium with 4.0-mg/l BAP for plant regeneration. As the irradiation dosage increased, the frequency of both somatic embryo formation and p...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Wang, J.-S., Sui, J.-M., Xie, Y.-D., Guo, H.-J., Qiao, L.-X., Zhao, L.-L., Yu, S.-L., Liu, L.-X. Tags: Biology Source Type: research
Radiation-induced motility alterations in medulloblastoma cells
This study was set up to analyse possible mechanisms underlying the potentially radiation-altered motility in medulloblastoma cells. Medulloblastoma cell lines D425 and Med8A were analyzed in migration and adhesion experiments with and without photon and carbon ion irradiation. Expression of integrins was determined by quantitative FACS analysis. Matrix metalloproteinase concentrations within cell culture supernatants were investigated by enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed using Student's t-test. Both photon and carbon ion irradiation significantly reduced chemotactic medulloblast...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Rieken, S., Rieber, J., Brons, S., Habermehl, D., Rief, H., Orschiedt, L., Lindel, K., Weber, K. J., Debus, J., Combs, S. E. Tags: Biology Source Type: research
Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident
Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing proc...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Shimura, T., Yamaguchi, I., Terada, H., Robert Svendsen, E., Kunugita, N. Tags: Reviews Source Type: research
Radiation occupational health interventions offered to radiation workers in response to the complex catastrophic disaster at the Fukushima Daiichi Nuclear Power Plant
The Fukushima Daiichi Nuclear Power Plant (NPP) 1 was severely damaged from the chain reaction of the Great East Japan Earthquake and Tsunami on 11 March 2011, and the consequent meltdown and hydrogen gas explosions. This resulted in the worst nuclear accident since the Chernobyl accident of 1986. Just as in the case of Chernobyl, emergency workers were recruited to conduct a wide range of tasks, including disaster response, rescuing activities, NPP containment, and radiation decontamination. This paper describes the types and efficacy of the various occupational health interventions introduced to the Fukushima NPP radiati...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Shimura, T., Yamaguchi, I., Terada, H., Okuda, K., Svendsen, E. R., Kunugita, N. Tags: Reviews Source Type: research
Heavy-ion-induced sucrose radicals investigated using EPR and UV spectroscopy
The potential use of a sucrose dosimeter for estimating both linear energy transfer (LET) and the absorbed dose of heavy ion and X-ray radiation was investigated. The stable free radicals were produced when sucrose was irradiated with heavy ions, such as helium, carbon, silicon and neon ions, and when the X-ray radiation was similar to the obtained electron paramagnetic resonance (EPR) spectra, which were ~7 mT wide and composed of several hyperfine structures. In addition, the total spin concentration resulting from heavy-ion irradiation increased linearly as the absorbed dose increased, and decreased logarithmically as t...
Source: Journal of Radiation Research - May 11, 2015 Category: Physics Authors: Nakagawa, K., Karakirova, Y., Yordanov, N. D. Tags: Reviews Source Type: research
Evaluation of the Flash effect in breast irradiation using TomoDirect: an investigational study
This study assessed the theoretical dose distribution resulting from Flash in breast irradiation using TomoDirect. A cylindrical phantom that enabled dose distribution of the breast was used for verifying the effect of planning target volume (PTV) contouring and Flash. A total of 18 Gy in 10 fractions were prescribed to the PTV. Five PTVs were then created by Contracting this contour by 0, 1, 2, 3, 4 and 5 mm, giving PTV-x. Flash ±x is defined by opening x (number) of the leaves. The Flash effect in the air was compared with each set-up error of 5, 10 and 15 mm, respectively. The minimum PTV dose from PTV-1 to PTV-3...
Source: Journal of Radiation Research - March 13, 2015 Category: Physics Authors: Kang, D. G., Park, S. I., Kim, S. H., Chung, M. J., Lee, K.-M., Lee, J. H. Tags: Physics Source Type: research
