MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Radiation Research' source. Mon, 06 Feb 2012 20:25:03 +0100 http://www.medworm.com/index.php?rid=5598599&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22229487%26dopt%3DAbstract Authors: Park HJ, Griffin RJ, Hui S, Levitt SH, Song CW Abstract We have reviewed the studies on radiation-induced vascular changes in human and experimental tumors reported in the last several decades. Although the reported results are inconsistent, they can be generalized as follows. In the human tumors treated with conventional fractionated radiotherapy, the morphological and functional status of the vasculature is preserved, if not improved, during the early part of a treatment course and then decreases toward the end of treatment. Irradiation of human tumor xenografts or rodent tumors with 5-10 Gy in a single dose causes relatively mild vascular damages, but increasing the radiation dose to higher than 10 Gy/fraction induces severe vascular damage resulting in reduced blood pe... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5598599 Mon, 09 Jan 2012 05:00:00 +0100 5598599 http://www.medworm.com/index.php?rid=5577913&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22214380%26dopt%3DAbstract Authors: Dallas LJ, Keith-Roach M, Lyons BP, Jha AN Abstract There is growing scientific, regulatory and public concern over anthropogenic input of radionuclides to the aquatic environment, especially given the issues surrounding existing nuclear waste, future energy demand and past or potential nuclear accidents. A change in the approach to how we protect the environment from ionizing radiation has also underlined the importance of assessing its impact on nonhuman biota. This review presents a thorough and critical examination of the available information on the effects of ionizing radiation on aquatic invertebrates, which constitute approximately 90% of extant life on the planet and play vital roles in ecosystem functioning. The aim of the review was to assess the progress made s... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5577913 Tue, 03 Jan 2012 05:00:00 +0100 5577913 http://www.medworm.com/index.php?rid=5577912&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22214381%26dopt%3DAbstract Authors: Hötte GJ, Lennon NL, Reynolds JV, Maher SG Abstract Radiation combined with chemotherapy (neo-CRT) is increasingly the standard of care for the treatment of esophageal cancer either as neoadjuvant therapy in multimodal protocols or as primary therapy. Unfortunately, ∼60% of patients demonstrate little or no response to neo-CRT. Accordingly, understanding the molecular mechanisms of resistance to therapy may underpin significant advances through the identification of nonresponders either before or early in treatment. We previously identified the RNPC1 gene, which is important in stabilizing p21, as being upregulated in the tumors of esophageal cancer patients who had a poor response to neo-CRT. We hypothesize that RNPC1 contributes to resistance to radiation therapy thro... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5577912 Tue, 03 Jan 2012 05:00:00 +0100 5577912 http://www.medworm.com/index.php?rid=5548636&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22188513%26dopt%3DAbstract Corrections: in the article "Inactivation of Aerobic and Hypoxic Cells from Three Different Cell Lines by Accelerated (3)He-, (12)C- and (20)Ne-Ion Beams" by Furusawa et al. Radiat Res. 2012 Jan;177(1):129-31 Authors: PMID: 22188513 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5548636 Thu, 29 Dec 2011 06:36:13 +0100 5548636 http://www.medworm.com/index.php?rid=5533075&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22175298%26dopt%3DAbstract Authors: Pearce LL, Zhang X, Martinez-Bosch S, Kerr PP, Khlangwiset P, Epperly MW, Fink MP, Greenberger JS, Peterson J Abstract l-Arginine is shown to protect hematopoietic progenitor (32D cl 3) cells from death due to exposure to γ radiation ((137)Cs). Some of the other intermediates in the urea cycle, namely ornithine and citrulline, plus urea itself, were not found to have any significant impact on cell survival after irradiation. Intriguingly, supplementation of irradiated cells with l-arginine results in decreased production of peroxynitrite, suggesting that suppression of superoxide generation by nitric oxide synthase in one or more microenvironments is an important factor in the observed radioprotection. The absence of any radioprotective effect of l-arginine in cells at 3%... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533075 Fri, 16 Dec 2011 05:00:00 +0100 5533075 http://www.medworm.com/index.php?rid=5533059&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22175299%26dopt%3DAbstract Authors: Kumar PR, Cheriyan VD, Seshadri M Abstract Inhabitants of the high-level natural radiation areas (>1 mSv year(-1)) of Kerala in southwest India were evaluated for basal damage (spontaneous DNA strand breaks and alkali-labile sites) by the alkaline comet assay and oxidative DNA damage (ENDO III- and hOGG1-sensitive sites) by the enzyme-modified comet assay. Of the 67 adult male subjects studied, 45 were from high-level natural radiation areas and 22 subjects were from a nearby normal-level natural radiation area (≤1 mSv year(-1)). Basal damage due to the age and residential area (normal-level natural radiation area/high-level natural radiation areas) of the donors showed significant interaction (P < 0.001) when all subjects were analyzed using a general linear model... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533059 Fri, 16 Dec 2011 05:00:00 +0100 5533059 http://www.medworm.com/index.php?rid=5533058&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22175300%26dopt%3DAbstract CBLB613: A TLR 2/6 Agonist, Natural Lipopeptide of Mycoplasma arginini , as a Novel Radiation Countermeasure. Radiat Res. 2011 Dec 16; Authors: Singh VK, Ducey EJ, Fatanmi OO, Singh PK, Brown DS, Purmal A, Shakhova VV, Gudkov AV, Feinstein E, Shakhov A Abstract To date, there are no safe and effective drugs available for protection against ionizing radiation damage. Therefore, a great need exists to identify and develop non-toxic agents that will be useful as radioprotectors or postirradiation therapies under a variety of operational scenarios. We have developed a new pharmacological agent, CBLB613 (a naturally occurring Mycoplasma-derived lipopeptide ligand for Toll-like receptor 2/6), as a novel radiation countermeasure. Using CD2F1 mice, we investigated CBLB613 for toxic... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533058 Fri, 16 Dec 2011 05:00:00 +0100 5533058 http://www.medworm.com/index.php?rid=5533077&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22171959%26dopt%3DAbstract This study demonstrates that automatic detection of dicentrics is a credible alternative for recent and acute cases of whole- and partial-body accidental exposures to ionizing radiation. PMID: 22171959 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533077 Thu, 15 Dec 2011 05:00:00 +0100 5533077 http://www.medworm.com/index.php?rid=5533076&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22171960%26dopt%3DAbstract Authors: Ozasa K, Shimizu Y, Suyama A, Kasagi F, Soda M, Grant EJ, Sakata R, Sugiyama H, Kodama K Abstract This is the 14th report in a series of periodic general reports on mortality in the Life Span Study (LSS) cohort of atomic bomb survivors followed by the Radiation Effects Research Foundation to investigate the late health effects of the radiation from the atomic bombs. During the period 1950-2003, 58% of the 86,611 LSS cohort members with DS02 dose estimates have died. The 6 years of additional follow-up since the previous report provide substantially more information at longer periods after radiation exposure (17% more cancer deaths), especially among those under age 10 at exposure (58% more deaths). Poisson regression methods were used to investigate the magnitude of the ra... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533076 Thu, 15 Dec 2011 05:00:00 +0100 5533076 http://www.medworm.com/index.php?rid=5533079&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22165823%26dopt%3DAbstract Authors: Lindholm C, Acheva A, Koivistoinen A, Perälä M, Heinävaara S, Jahns J, Salomaa S, Hildebrandt G Abstract In studies reported in the 1960s and in several investigations since, plasma from irradiated individuals was shown to induce chromosomal aberrations when transferred into normal blood cultures. In the present study, the aim was to investigate the occurrence of these clastogenic factors (CF) using markers representing DNA damage produced in reporter lymphocytes that are treated with plasma from locally exposed individuals. Blood plasma was obtained from clinical patients with benign conditions before and after they had received radiation to small treatment volumes. Three patient groups were studied: (I) marginal resected basal cell carcinoma, (II) painful osteoarthrit... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533079 Tue, 13 Dec 2011 05:00:00 +0100 5533079 http://www.medworm.com/index.php?rid=5533078&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22165824%26dopt%3DAbstract p21 Protects "Super p53" Mice from the Radiation-Induced Gastrointestinal Syndrome. Radiat Res. 2011 Dec 13; Authors: Sullivan JM, Jeffords LB, Lee CL, Rodrigues R, Ma Y, Kirsch DG Abstract Exposure of the gastrointestinal (GI) tract to high doses of radiation can lead to lethality from the GI syndrome. Although the molecular mechanism regulating the GI syndrome remains to be fully defined, we have recently demonstrated that p53 within the GI epithelial cells controls the radiation-induced GI syndrome. Mice lacking p53 in the GI epithelium were sensitized to the GI syndrome, while transgenic mice with one additional copy of p53 called "Super p53" mice were protected from the GI syndrome. Here, we crossed Super p53 mice to p21(-/-) mice that lack the cyclin-dependent kinase ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533078 Tue, 13 Dec 2011 05:00:00 +0100 5533078 http://www.medworm.com/index.php?rid=5533080&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22149991%26dopt%3DAbstract In this study we show that signals generated in vivo in the bone marrow of mice irradiated with 4 Gy γ rays 18 h to 15 months previously are able to induce DNA damage and apoptosis in nonirradiated bone marrow cells but that comparable signals are not detected at earlier times postirradiation or at doses below 100 mGy. Bone marrow cells of both CBA/Ca and C57BL/6 genotypes exhibit responses to signals produced by either irradiated CBA/Ca or C57BL/6 mice, and the responses are mediated by the cytokines FasL and TNF-α converging on a COX-2-dependent pathway. The findings are consistent with indirect inflammatory signaling induced as a response to the initial radiation damage rather than to direct signaling between irradiated and nonirradiated cells. The findings also demonstrate the import... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533080 Fri, 09 Dec 2011 05:00:00 +0100 5533080 http://www.medworm.com/index.php?rid=5533082&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22149957%26dopt%3DAbstract This study quantified the effects of protracted exposure to low-dose/low-dose-rate γ rays with and without acute exposure to protons on the response of immune and other cell populations. C57BL/6 mice were irradiated with (57)Co (0.05 Gy at 0.025 cGy/h); subsets were subsequently exposed to high-dose/high-dose-rate proton radiation (250 MeV; 2 or 3 Gy at 0.5 Gy/min). Analyses were performed at 4 and 17 days postexposure. Spleen and thymus masses relative to body mass were decreased on day 4 after proton irradiation with or without pre-exposure to γ rays; by day 17, however, the decrease was attenuated by the priming dose. Proton dose-dependent decreases, either with or without pre-exposure to γ rays, occurred in white blood cell, lymphocyte and granulocyte counts in blood but not in sple... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533082 Wed, 07 Dec 2011 05:00:00 +0100 5533082 http://www.medworm.com/index.php?rid=5533081&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22149958%26dopt%3DAbstract Authors: Adams MJ, Grant EJ, Kodama K, Shimizu Y, Kasagi F, Suyama A, Sakata R, Akahoshi M Abstract Whole-body and thoracic ionizing radiation exposure are associated with increased cardiovascular disease (CVD) risk. In atomic bomb survivors, radiation dose is also associated with increased hypertension incidence, suggesting that radiation dose may be associated with chronic renal failure (CRF), thus explaining part of the mechanism for increased CVD. Multivariate Poisson regression was used to evaluate the association of radiation dose with various definitions of chronic kidney disease (CKD) mortality in the Life Span Study (LSS) of atomic bomb survivors. A secondary analysis was performed using a subsample for whom self-reported information on hypertension and diabetes, the two b... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5533081 Wed, 07 Dec 2011 05:00:00 +0100 5533081 http://www.medworm.com/index.php?rid=5492980&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22141411%26dopt%3DAbstract In this study, we found that refractoriness to ultraviolet (UVC) light-induced cell death was increased in UVC-radiation-sensitive cells derived from Cockayne syndrome patients when the cells were precultured in medium supplemented with recombinant annexin II (rANX II). In CS3BES cells, an immortal cell line derived from Cockayne syndrome patients, the rANX II supplementation-induced UVC-radiation resistance was suppressed by treatment with an anti-annexin II antibody and EGTA. The amount of biotinylated annexin II on the cell surface increased in the rANX II-supplemented cells but did not increase in the cells that were cotreated with rANX II and EGTA. The capacity to remove UVC-radiation-damaged DNA, (6-4) photoproducts and cyclobutane pyrimidine dimers, was the same in cells that were p... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492980 Thu, 01 Dec 2011 05:00:00 +0100 5492980 http://www.medworm.com/index.php?rid=5492979&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22141412%26dopt%3DAbstract Correction: in the article "Childhood Exposure to Ionizing Radiation to the Head and Risk of Schizophrenia" by Sadetzki et al. Radiat Res. 2011 Dec;176(6):849 Authors: PMID: 22141412 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492979 Thu, 01 Dec 2011 05:00:00 +0100 5492979 http://www.medworm.com/index.php?rid=5492982&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22128784%26dopt%3DAbstract Authors: Laiakis EC, Hyduke DR, Fornace AJ Abstract Metabolomics on easily accessible biofluids has the potential to provide rapid identification and distinction between stressors and inflammatory states. In the event of a radiological event, individuals with underlying medical conditions could present with similar symptoms to radiation poisoning, prominently nausea, diarrhea, vomiting and fever. Metabolomics of radiation exposure in mice has provided valuable biomarkers, and in this study we aimed to identify biomarkers of lipopolysaccharide (LPS) exposure to compare and contrast with ionizing radiation. LPS treatment leads to a severe inflammatory response and a cytokine storm, events similar to radiation exposure, and LPS exposure can recapitulate many of the responses seen in s... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492982 Wed, 30 Nov 2011 05:00:00 +0100 5492982 http://www.medworm.com/index.php?rid=5492981&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22128785%26dopt%3DAbstract In this study, C57BL/6 mice were used to determine the extent to which G-CSF and lipopolysaccharide (LPS, which simulates infection by gram-negative bacteria) alter the expression of genes that are either radiation-responsive or non-responsive, i.e., show potential for use as endogenous controls. Mice were acutely exposed to (60)Co γ rays at either 0 Gy or 6 Gy. Two hours later the animals were injected with either 0.1 mg/kg of G-CSF or 0.3 mg/kg of LPS. Expression levels of 96 different gene targets were evaluated in peripheral blood after an additional 4 or 24 h using real-time quantitative PCR. The results indicate that the expression levels of some genes are altered by LPS, but altered expression after G-CSF treatment was generally not observed. The expression levels of many genes the... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492981 Wed, 30 Nov 2011 05:00:00 +0100 5492981 http://www.medworm.com/index.php?rid=5492985&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22103271%26dopt%3DAbstract Authors: Lee M, Urata SM, Aguilera JA, Perry CC, Milligan JR Abstract The DNA-binding proteins that are present in chromatin significantly affect the sensitivity of cells to ionizing radiation and to the radiation chemistry of DNA damage. The interaction between protein and DNA modifies the radiation chemistry of the latter. To model these processes, we have examined the effects of ionizing radiation on the minichromosome form of SV40 (which contains histone proteins arranged in nucleosomes) and also on plasmid DNA in the presence of lysozyme. Although high concentrations of lysozyme can bring about an extensive radioprotection by condensation of the plasmid, at lower levels it still produces significant radioprotective effects under conditions where this associative phase separati... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492985 Mon, 21 Nov 2011 05:00:00 +0100 5492985 http://www.medworm.com/index.php?rid=5492984&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22103272%26dopt%3DAbstract Authors: Coleman CN, Whitcomb RC, Miller C, Noska MA PMID: 22103272 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492984 Mon, 21 Nov 2011 05:00:00 +0100 5492984 http://www.medworm.com/index.php?rid=5492983&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22103273%26dopt%3DAbstract Authors: Koana T, Takahashi T, Tsujimura H Abstract The third instar larvae of Drosophila were irradiated with X rays, and the somatic mutation frequency in their wings was measured after their eclosion. In the flies with normal DNA repair and apoptosis functions, 0.2 Gy irradiation at 0.05 Gy/min reduced the frequency of the so-called small spot (mutant cell clone with reduced reproductive activity) compared with that in the sham-irradiated flies. When apoptosis was suppressed using the baculovirus p35 gene, the small spot frequency increased four times in the sham-irradiated control group, but the reduction by the 0.2-Gy irradiation was still evident. In a non-homologous end joining-deficient mutant, the small spot frequency was also reduced by 0.2 Gy radiation. In a mutant defic... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492983 Mon, 21 Nov 2011 05:00:00 +0100 5492983 http://www.medworm.com/index.php?rid=5492986&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22087741%26dopt%3DAbstract Authors: Khaled S, Gupta KB, Kucik DF Abstract Exposure to radiation from a variety of sources is associated with increased risk of heart disease and stroke. Since radiation also induces inflammation, a possible mechanism is a change in the adhesiveness of vascular endothelial cells, triggering pro-atherogenic accumulation of leukocytes. To investigate this mechanism at the cellular level, the effect of X rays on adhesiveness of cultured human aortic endothelial cells (HAECs) was determined. HAECs were grown as monolayers and exposed to 0 to 30 Gy X rays, followed by measurement of adhesiveness under physiological shear stress using a flow chamber adhesion assay. Twenty-four hours after irradiation, HAEC adhesiveness was increased, with a peak effect at 15 Gy. Radiation had no sign... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5492986 Tue, 15 Nov 2011 05:00:00 +0100 5492986 http://www.medworm.com/index.php?rid=5418863&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22077335%26dopt%3DAbstract Authors: Lazarov E, Arazi L, Efrati M, Cooks T, Schmidt M, Keisari Y, Kelson I Abstract Diffusing alpha-emitter radiation therapy (DaRT) is a proposed new form of brachytherapy using ? particles to treat solid tumors. The method relies on implantable (224)Ra-loaded sources that continually release short-lived ?-particle-emitting atoms that spread inside the tumor over a few millimeters. This treatment was demonstrated to have a significant effect on tumor growth in murine and human-derived models, but the degree of tumor response varied across cell lines. Tumor response was found to correlate with the degree of radionuclide spread inside the tumor. In this work we examined the radiosensitivity of individual cells to determine its relationship to tumor response. Cells were irradiate... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418863 Fri, 11 Nov 2011 05:00:00 +0100 5418863 http://www.medworm.com/index.php?rid=5418862&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22077336%26dopt%3DAbstract Authors: Hu B, Grabham P, Nie J, Balajee AS, Zhou H, Hei TK, Geard CR Abstract Exposure to ionizing radiation may induce a heritable genomic instability phenotype that results in a persisting and enhanced genetic and functional change among the progeny of irradiated cells. Since radiation-induced bystander effects have been demonstrated with a variety of biological end points under both in vitro and in vivo conditions, this raises the question whether cytoplasmic irradiation or the radiation-induced bystander effect can also lead to delayed genomic instability. In the present study, we used the Radiological Research Accelerator Facility charged-particle microbeam for precise nuclear or cytoplasmic irradiation. The progeny of irradiated and the bystander human hamster hybrid (A(L)) ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418862 Fri, 11 Nov 2011 05:00:00 +0100 5418862 http://www.medworm.com/index.php?rid=5418861&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22077337%26dopt%3DAbstract Authors: Wang XC, Tian LL, Tian J, Jiang XY Abstract SKP2 is the substrate recognition subunit of the SCF(SKP2) ubiquitin ligase complex. It is implicated in ubiquitin-mediated degradation of the cyclin-dependent kinase (CDK) inhibitor p27(KIP1) and positively regulates the G(1)/S transition. Overexpression of SKP2 has been found in many kinds of tumors. In the present study, we found that SKP2 expression levels increased in esophageal squamous cell carcinoma tissues. Elevated expression of SKP2 correlated significantly with tumor stage and positive lymph node metastasis (P < 0.05). Moreover, a significantly negative correlation was found between SKP2 expression and the survival of patients who received radiotherapy (P < 0.05). At the molecular level, induced expression of SK... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418861 Fri, 11 Nov 2011 05:00:00 +0100 5418861 http://www.medworm.com/index.php?rid=5418860&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22077338%26dopt%3DAbstract Authors: Britten RA, Davis LK, Johnson AM, Keeney S, Siegel A, Sanford LD, Singletary SJ, Lonart GR Abstract Exposure to galactic cosmic radiation (GCR) is considered to be a potential health risk in long-term space travel, and it represents a significant risk to the central nervous system (CNS). The most harmful component of GCR is the HZE [high-mass, highly charged (Z), high-energy] particles, e.g. (56)Fe. In previous ground-based experiments, exposure to high doses of HZE-particle radiation induced pronounced deficits in hippocampus-dependent learning and memory in rodents. Recent data suggest that glutamatergic transmission in hippocampal synaptosomes is impaired after low (60 cGy) doses of 1 GeV (56)Fe particles, which could lead to impairment of hippocampus-dependent spatial ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418860 Fri, 11 Nov 2011 05:00:00 +0100 5418860 http://www.medworm.com/index.php?rid=5418859&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22077339%26dopt%3DAbstract This study investigated the effects of ionizing radiation on the microenvironment and intercellular communication as it relates to esophageal carcinogenesis. We demonstrate that normal esophageal epithelial cells exhibited increased migration and invasion when cultured in the presence of irradiated stromal fibroblasts or with conditioned medium derived from irradiated stromal fibroblasts. Cytokine antibody arrays and ELISAs were used to identify hepatocyte growth factor (HGF) as an abundant protein that is secreted by esophageal fibroblasts at twofold increased levels in culture medium after ? irradiation. Reverse transcription qPCR analysis confirmed an approximately 50% increase in mRNA levels for HGF at 1 h in irradiated fibroblasts compared to unirradiated controls. Recombinant HGF sti... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418859 Fri, 11 Nov 2011 05:00:00 +0100 5418859 http://www.medworm.com/index.php?rid=5418865&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22059980%26dopt%3DAbstract This study investigated the biological effects and adaptive responses induced by single and repeated in vivo computed tomography (CT) scans. We postulated that, through the induction of low-level oxidative stress, repeated low-dose CT scans (20 mGy, 2 days/week, 10 weeks) could protect mice (C57BL/6) from acute effects of high-dose radiation (1 Gy, 2 Gy). The micronucleated reticulocyte (MN-RET) count increased linearly after exposure to single CT scans of doses ranging from 20 to 80 mGy (P = 0.033). Ten weeks of repeated CT scans (total dose 400 mGy) produced a slight reduction in spontaneous MN-RET levels relative to levels in sham CT-scanned mice (P = 0.04). Decreases of nearly 10% in γ-H2AX fluorescence levels were observed in the repeated CT-scanned mice after an in vitro challenge d... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418865 Mon, 07 Nov 2011 05:00:00 +0100 5418865 http://www.medworm.com/index.php?rid=5418864&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22059981%26dopt%3DAbstract Authors: Ohnishi T Abstract On March 11, 2011 eastern Japan was struck by a magnitude 9.0 earthquake and an enormous tsunami, over 13 m in height, which together killed over 20,500 people and resulted in the evacuation of over 320,000 people from the devastated areas. This paper describes the damage sustained by the Fukushima-Daiichi nuclear power plant during this unpredicted major natural disaster and the events that happened in the months after this accident. The events occurring at the Fukushima-Daiichi nuclear power plant, the actions taken to minimize the effects of the damage to the plant and to protect the public, and the points at which the responses proved to be inadequate all offer lessons that will be of value to those planning for and responding to future natural disas... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5418864 Mon, 07 Nov 2011 05:00:00 +0100 5418864 http://www.medworm.com/index.php?rid=5379189&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22050452%26dopt%3DAbstract In this study, using a mouse model that has been well characterized with respect to its susceptibility to both radiation-induced chromosomal instability and acute myeloid leukemia, we investigated whether the underlying signaling mechanism was an inflammatory process by studying the effects of a nonsteroidal anti-inflammatory drug. Treated mice showed significant reduction in expression of the chromosomal instability phenotype 100 days postirradiation associated with reduced expression of inflammatory markers. The data support the hypothesis that the radiation-induced chromosomal instability phenotype is not an intrinsic property of the cells but a consequence of inflammatory processes having the potential to contribute secondary damage expressed as nontargeted and delayed radiation effect... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5379189 Thu, 03 Nov 2011 04:00:00 +0100 5379189 http://www.medworm.com/index.php?rid=5379188&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22050453%26dopt%3DAbstract Authors: Northum JD, Guetersloh SB, Braby LA Abstract Delta-ray transport is important in microdosimetric studies, and how Monte Carlo models handle delta electrons using condensed histories is important for accurate simulation. The purpose of this study was to determine how well FLUKA can simulate energy deposition spectra in a tissue-equivalent proportional counter (TEPC) and produce a reliable estimate of delta-ray events produced when a TEPC is exposed to high-energy heavy ions (HZE) like those in the galactic cosmic-ray (GCR) environment. A 1.27-cm spherical TEPC with a low-pressure gas simulating a 1-μm site, typical of the one flown on the ISS, was constructed in FLUKA, and its response was compared to experimental data for an (56)Fe-ion beam at 360 MeV/nucleon. Several nar... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5379188 Thu, 03 Nov 2011 04:00:00 +0100 5379188 http://www.medworm.com/index.php?rid=5360868&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22026716%26dopt%3DAbstract Authors: Sadetzki S, Chetrit A, Mandelzweig L, Nahon D, Freedman L, Susser E, Gross R Abstract While the association between exposure to ionizing radiation and cancer is well established, its association with schizophrenia is unclear. The aim of our study was to assess risk of schizophrenia after childhood exposure to ionizing radiation to the head (mean dose: 1.5 Gy). The study population included an exposed group of 10,834 individuals irradiated during childhood for treatment of tinea capitis in the 1950s and two unexposed comparison groups of 5392 siblings and 10,834 subjects derived from the National Population Registry individually matched to the exposed group by age, sex (when possible), country of birth, and year of immigration to Israel. These groups were followed for a med... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5360868 Mon, 31 Oct 2011 07:12:58 +0100 5360868 http://www.medworm.com/index.php?rid=5360867&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22026717%26dopt%3DAbstract Robert katz (1917-2011). Radiat Res. 2011 Nov;176(5):692-3 Authors: Waligorski MP, Cucinotta FA PMID: 22026717 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5360867 Mon, 31 Oct 2011 07:12:07 +0100 5360867 http://www.medworm.com/index.php?rid=5360866&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22029841%26dopt%3DAbstract This study provides further evidence for the importance of intercellular signaling in modulated exposures, where dose gradients are present, and may inform the refinement of established radiobiological models to facilitate the optimization of advanced radiotherapy treatment plans. PMID: 22029841 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5360866 Wed, 26 Oct 2011 04:00:00 +0100 5360866 http://www.medworm.com/index.php?rid=5360865&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22029842%26dopt%3DAbstract Authors: Albrecht H, Durbin-Johnson B, Yunis R, Kalanetra KM, Wu S, Chen R, Stevenson TS, Rocke DM Abstract Although human exposure to low-dose ionizing radiation can occur through a variety of sources, including natural, medical, occupational and accidental, the true risks of low-dose ionizing radiation are still poorly understood in humans. Here, the global transcriptional responses of human skin after ex vivo exposure to low (0.05 Gy) and high (5 Gy) doses of X rays and of time in culture (0 Gy) at 0, 2, 8 and 30 h postirradiation were analyzed and compared. Responses to low and high doses differed quantitatively and qualitatively. Differentially expressed genes fell into three groups: (1) unique genes defined as responsive to either 0.05 or 5 Gy but not both and also responsive... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5360865 Wed, 26 Oct 2011 04:00:00 +0100 5360865 http://www.medworm.com/index.php?rid=5360870&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22026585%26dopt%3DAbstract Authors: Vozilova AV, Shagina NB, Degteva MO, Edwards AA, Ainsbury EA, Moquet JE, Hone P, Lloyd DC, Fomina JN, Darroudi F Abstract This paper presents the results of a feasibility cytogenetic study using the fluorescence in situ hybridization (FISH) translocation assay for residents of villages located on the Techa River (Southern Urals, Russia) contaminated with liquid radioactive wastes from the Mayak plutonium facility in 1949-1956. The study was conducted with two groups of donors that differed in their main pathways of exposure. The first group comprised 18 residents of the middle Techa region who were exposed predominantly from ingestion of radionuclides (mostly (89,90)Sr) via the river water and local foodstuffs. The second group included 20 residents of Metlino, the closest... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5360870 Tue, 25 Oct 2011 04:00:00 +0100 5360870 http://www.medworm.com/index.php?rid=5360869&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22026586%26dopt%3DAbstract This study examined the terminal maturation of megakaryocytes and platelet production in hematopoietic stem/progenitor cells (HSPCs) exposed to ionizing radiation. Highly purified CD34(+) cells derived from human placental/umbilical cord blood were exposed to X rays (2 Gy, 150 kVp, 20 mA; 0.5-mm aluminum and 0.3-mm copper filters) at a dose rate of approximately 1 Gy/min and then cultured in a serum-free medium supplemented with thrombopoietin and interleukin-3. The number of cells generated from X-irradiated CD34(+) cells decreased with the time in culture. However, the fraction of CD34(+)Tie-2(+) and CD41(+)Tie-2(+) cells among the total cells generated from X-irradiated cells increased significantly in comparison to nonirradiated controls on day 7. In addition, the CD42a(+) particles, w... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5360869 Tue, 25 Oct 2011 04:00:00 +0100 5360869 http://www.medworm.com/index.php?rid=5344292&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22013884%26dopt%3DAbstract We examined the widely used dietary supplement genistein given at two dietary levels (750 or 3750 mg/kg) to Fischer rats irradiated with 12 Gy to the lung or 8 Gy to the lung + 4 Gy to the whole body excluding the head and tail (whole torso). We found that genistein had promising mitigating effects on oxidative damage, pneumonitis and fibrosis even at late times (36 weeks) when drug treatment was initiated 1 week after irradiation and stopped at 28 weeks postirradiation. The higher dose of genistein showed no greater beneficial effect. Combined lung and whole-torso irradiation caused more lung-related severe morbidity resulting in euthanasia of the animals than lung irradiation alone. PMID: 22013884 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5344292 Thu, 20 Oct 2011 04:00:00 +0100 5344292 http://www.medworm.com/index.php?rid=5344291&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22013885%26dopt%3DAbstract Authors: Singh PK, Wise SY, Ducey EJ, Fatanmi OO, Elliott TB, Singh VK Abstract The purpose of this study was to elucidate the role of α-tocopherol succinate (α-TS) in protecting mice from gastrointestinal syndrome induced by total-body irradiation. CD2F1 mice were injected subcutaneously with 400 mg/kg of α-TS and exposed to different doses of (60)Co γ radiation, and 30-day survival was monitored. Jejunum sections were analyzed for crypts and villi, PUMA (p53 upregulated modulator of apoptosis), and apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling - TUNEL). The crypt regeneration in irradiated mice was evaluated by 5-bromo-2-deoxyuridine (BrdU). Bacterial translocation from gut to heart, spleen and liver in α-TS-treated and irradiated mice was evaluated... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5344291 Thu, 20 Oct 2011 04:00:00 +0100 5344291 http://www.medworm.com/index.php?rid=5344290&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22014293%26dopt%3DAbstract Authors: Wang Y, Liu L, Zhou D Abstract Exposure to a moderate or high total-body dose of radiation induces not only acute bone marrow suppression but also residual (or long-term) bone marrow injury. The induction of residual bone marrow injury is primarily attributed to the induction of hematopoietic cell senescence by ionizing radiation. However, the mechanisms underlying radiation-induced hematopoietic cell senescence are not known and thus were investigated in the present study. Using a well-established long-term bone marrow cell culture system, we found that radiation induced hematopoietic cell senescence at least in part via activation of p38 mitogen-activated protein kinase (p38). This suggestion is supported by the finding that exposure to radiation selectively activated p3... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5344290 Thu, 20 Oct 2011 04:00:00 +0100 5344290 http://www.medworm.com/index.php?rid=5325437&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21988547%26dopt%3DAbstract Authors: Thierry-Chef I, Simon SL, Weinstock RM, Kwon D, Linet MS Abstract The assessment of potential benefits versus harms from mammographic examinations as described in the controversial breast cancer screening recommendations of the U.S. Preventive Task Force included limited consideration of absorbed dose to the fibroglandular tissue of the breast (glandular tissue dose), the tissue at risk for breast cancer. Epidemiological studies on cancer risks associated with diagnostic radiological examinations often lack accurate information on glandular tissue dose, and there is a clear need for better estimates of these doses. Our objective was to develop a quantitative summary of glandular tissue doses from mammography by considering sources of variation over time in key parameters, ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5325437 Wed, 12 Oct 2011 04:00:00 +0100 5325437 http://www.medworm.com/index.php?rid=5325436&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21988573%26dopt%3DAbstract Authors: Yang H, Magpayo N, Rusek A, Chiang IH, Sivertz M, Held KD Abstract In space, astronauts are exposed to radiation fields consisting of energetic protons and high atomic number, high-energy (HZE) particles at very low dose rates or fluences. Under these conditions, it is likely that, in addition to cells in an astronaut's body being traversed by ionizing radiation particles, unirradiated cells can also receive intercellular bystander signals from irradiated cells. Thus this study was designed to determine the dependence of DNA damage induction on dose at very low fluences of charged particles. Novel techniques to quantify particle fluence have been developed at the NASA Space Radiation Biology Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The approach uses a lar... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5325436 Wed, 12 Oct 2011 04:00:00 +0100 5325436 http://www.medworm.com/index.php?rid=5325435&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21988611%26dopt%3DAbstract Authors: Kavet R, Hooper C, Buffler P, Does M Abstract It has been suggested that residential exposure to contact currents may be more directly associated with the potential for an increased risk of leukemia in childhood than magnetic fields. Contact current exposure occurs when a child contacts a bathtub's water fixtures, which are usually contiguous with a residence's electrical ground, and when the drainpipe is conductive. The Northern California Childhood Leukemia Study (NCCLS) is the only epidemiological study known to address whether contact current may confound the reported association between residential magnetic fields and childhood leukemia. The study contributed contact voltage and magnetic-field data for over 500 residences of leukemia cases and control children. We com... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5325435 Wed, 12 Oct 2011 04:00:00 +0100 5325435 http://www.medworm.com/index.php?rid=5325438&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21988524%26dopt%3DAbstract In conclusion, age at menopause was thought to decrease with increasing radiation dose for both natural and artificial menopause occurring at least 5 years after the exposure. PMID: 21988524 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5325438 Tue, 11 Oct 2011 04:00:00 +0100 5325438 http://www.medworm.com/index.php?rid=5325439&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21980958%26dopt%3DAbstract Tumor Blood Vessel "Normalization" Improves the Therapeutic Efficacy of Boron Neutron Capture Therapy (BNCT) in Experimental Oral Cancer. Radiat Res. 2011 Oct 10; Authors: Molinari AJ, Pozzi EC, Hughes AM, Heber EM, Garabalino MA, Thorp SI, Miller M, Itoiz ME, Aromando RF, Nigg DW, Trivillin VA, Schwint AE Abstract We previously demonstrated the efficacy of BNCT mediated by boronophenylalanine (BPA) to treat tumors in a hamster cheek pouch model of oral cancer with no normal tissue radiotoxicity and moderate, albeit reversible, mucositis in precancerous tissue around treated tumors. It is known that boron targeting of the largest possible proportion of tumor cells contributes to the success of BNCT and that tumor blood vessel normalization improves drug delivery to the tumo... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5325439 Mon, 10 Oct 2011 04:00:00 +0100 5325439 http://www.medworm.com/index.php?rid=5325440&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21980927%26dopt%3DAbstract Authors: Koya PK, Chougaonkar MP, Predeep P, Jojo PJ, Cheriyan VD, Mayya YS, Seshadri M Abstract A population-based 1:3 age-matched case-control study was conducted during 2006-2009 to assess the role of high-level natural radiation (>1 mSv/year) on congenital mental retardation and cleft lip/palate in the southwest coastal area of Kerala. Dosimetry was carried out in the house where parents resided during conception and the subsequent two trimesters of pregnancy of the study subject. Conditional logistic regression did not suggest any statistically significant association of either mental retardation (n = 445) or cleft lip/palate (n = 116) with high-level natural radiation. The odds of mental retardation and cleft lip/palate among those exposed to high-level natural radiation r... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5325440 Fri, 07 Oct 2011 04:00:00 +0100 5325440 http://www.medworm.com/index.php?rid=5276605&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21943187%26dopt%3DAbstract Authors: Magae J, Furukawa C, Ogata H Abstract Irradiation time and dose rate are important factors in the evaluation of radiation risk for human health. We previously proposed a novel dose-rate effect model, the modified exponential (MOE) model, which predicts that radiation risks decline exponentially as the dose rate decreases. Here we show that, during the early phase of exposure, up to 1000 h, the proliferation of cells continuously exposed to γ rays at a constant dose rate is gradually suppressed, even as the total dose increases. This trend holds for a number of cell lines including tumor cells, nontransformed fibroblasts and leukocytes. The accumulation of total dose by longer exposure times does not increase this suppressive effect even in cells with a defective DNA repa... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5276605 Sat, 01 Oct 2011 04:00:00 +0100 5276605 http://www.medworm.com/index.php?rid=5276604&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21943188%26dopt%3DAbstract Elaine ron 1943-2010. Radiat Res. 2011 Oct;176(4):533-4 Authors: Linet M, Kleinerman R, Mabuchi K PMID: 21943188 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5276604 Sat, 01 Oct 2011 04:00:00 +0100 5276604 http://www.medworm.com/index.php?rid=5276603&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21943189%26dopt%3DAbstract Further consideration of the incidence of childhood leukaemia around nuclear power plants in Great Britain Further consideration of the incidence of childhood leukaemia around nuclear power plants in Great Britain . Committee on Medical Aspects of Radiation in the Environment (COMARE) Fourteenth Report . HPA , Chilton, UK , 2011 ( available at http://www.comare.org.uk/ ). Radiat Res. 2011 Oct;176(4):535-7 Authors: Osborne RV PMID: 21943189 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5276603 Sat, 01 Oct 2011 04:00:00 +0100 5276603 http://www.medworm.com/index.php?rid=5259530&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21939290%26dopt%3DAbstract Authors: Bernard ME, Kim H, Epperly MW, Franicola D, Zhang X, Houghton F, Shields D, Wang H, Bakkenist CJ, Frantz MC, Forbeck EM, Goff JP, Wipf P, Berhane H, Greenberger JS Abstract Fanconi anemia (FA) is an inherited disorder characterized by defective DNA repair and cellular sensitivity to DNA crosslinking agents. Clinically, FA is associated with high risk for marrow failure, leukemia and head and neck squamous cell carcinoma (HNSCC). Radiosensitivity in FA patients compromises the use of total-body irradiation for hematopoietic stem cell transplantation and radiation therapy for HNSCC. A radioprotector for the surrounding tissue would therefore be very valuable during radiotherapy for HNSCC. Clonogenic radiation survival curves were determined for pre- or postirradiation treatm... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5259530 Thu, 22 Sep 2011 04:00:00 +0100 5259530 http://www.medworm.com/index.php?rid=5259531&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21936607%26dopt%3DAbstract This study examined the mortality risks associated with exposure to radon, external γ rays and long-lived radionuclides (LLR) in the French "post-55" sub-cohort, which includes uranium miners first employed between 1956 and 1990 for whom all three types of exposure were assessed individually. Exposure-risk relationships were estimated with linear excess relative risk models and a 5-year lag time. The post-55 sub-cohort includes 3377 miners, contributing 89 405 person-years, followed up through the end of 1999 with a mean follow-up of 26.5 years. Mean cumulative exposure was 17.8 WLM for radon, 54.7 mSv for γ rays, and 1632 Bq.m(-3).h for LLR. Among the 611 deaths observed, 66 were due to lung cancer. Annual individual exposures were significantly correlated. Increased mortality was obser... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5259531 Wed, 21 Sep 2011 04:00:00 +0100 5259531 http://www.medworm.com/index.php?rid=5218344&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21910583%26dopt%3DAbstract Authors: Wilson DA, Brigantic A, Morgan WF Abstract Studies of health effects in animals after exposure to internally deposited radionuclides were intended to supplement observational studies in humans. Both nuclear workers and Beagle dogs have exhibited plutonium-associated lung fibrosis; however, the dogs' smaller gene pool may limit the applicability of findings to humans. Data on Beagles that inhaled either plutonium-238 dioxide ((238)PuO(2)) or plutonium-239 dioxide ((239)PuO(2)) were analyzed. Wright's Coefficient of Inbreeding was used to measure genetic or familial susceptibility and was assessed as an explanatory variable when modeling the association between lung fibrosis incidence and plutonium exposure. Lung fibrosis was diagnosed in approximately 80% of the exposed dog... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5218344 Mon, 12 Sep 2011 04:00:00 +0100 5218344 http://www.medworm.com/index.php?rid=5218343&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21910584%26dopt%3DAbstract In this study, we compared radioresistance in two types of non-small cell lung cancer (NSCLC) cells, NCI-H460 and A549, and investigated the signaling pathways that confer radioresistance. In radioresistant cells, exposure to radiation led to overexpression of PIM1 and reduction of protein phosphatases (PP2A and PP5), which induced translocation of PIM1 into the nucleus. Increased nuclear PIM1 phosphorylated PRAS40. Consequently, pPRAS40 made a trimeric complex with 14-3-3 and AKT-activated pFOXO3a, which then moved rapidly to the cytoplasm. Cytoplasmic retention of FOXO3a was associated with downregulation of proapoptotic genes and possibly radioresistance. On the other hand, no suppressive effect of radiation on protein phosphatases was detected and, concomitantly, protein phosphatases d... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5218343 Mon, 12 Sep 2011 04:00:00 +0100 5218343 http://www.medworm.com/index.php?rid=5218346&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21899432%26dopt%3DAbstract Authors: Veldwijk MR, Trah J, Wang M, Maier P, Fruehauf S, Zeller WJ, Herskind C, Wenz F Abstract Gene therapy-mediated overexpression of superoxide dismutases (SOD) appears to be a promising strategy for modulating radiosensitivity based on detoxification of superoxide radicals and suppression of apoptosis. Using recombinant lentiviral-based vectors, the effects of SOD overexpression on both were tested in human lymphoblastoid cells (TK6) that are sensitive to radiation-induced apoptosis. TK6 cells were transduced with vectors containing CuZnSOD, MnSOD or inverted MnSOD (MSODi) cDNA. Gene transfer efficiency, SOD activity, superoxide-radical resistance, apoptosis and clonogenic survival were determined. A six- to eightfold increase in SOD activity was observed after transduction, ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5218346 Wed, 07 Sep 2011 04:00:00 +0100 5218346 http://www.medworm.com/index.php?rid=5218345&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21899433%26dopt%3DAbstract In this study, the radioprotective efficacy of sesamol, a natural antioxidant, was investigated in aqueous solution of plasmid DNA (pBR322) and compared with that of melatonin, a known antioxidant-based radioprotector. Thermal denaturation studies on irradiated calf thymus DNA were also carried out with sesamol and melatonin. Sesamol demonstrated greater radioprotective efficacy in both plasmid DNA and calf thymus DNA. To assess the radical scavenging capacity of sesamol and melatonin, 2-deoxyribose degradation, DPPH and ABTS assays were performed. Sesamol exhibited more scavenging capacity compared to melatonin. In vitro studies with V79 cells showed that sesamol is 20 times more potent than melatonin. It is proposed that the greater radioprotective efficacy of sesamol could be due to its... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5218345 Wed, 07 Sep 2011 04:00:00 +0100 5218345 http://www.medworm.com/index.php?rid=5218347&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21883022%26dopt%3DAbstract Authors: Ryan JL, Krishnan S, Movsas B, Coleman CN, Vikram B, Yoo SS PMID: 21883022 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5218347 Thu, 01 Sep 2011 04:00:00 +0100 5218347 http://www.medworm.com/index.php?rid=5174947&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21867428%26dopt%3DAbstract Authors: Glazer PM, Grandis J, Powell SN, Brown JM, Helleday T, Bristow R, Powis G, Hill RP, Le QT, Pelroy R, Mohla S, Bernhard EJ PMID: 21867428 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174947 Tue, 30 Aug 2011 07:52:33 +0100 5174947 http://www.medworm.com/index.php?rid=5174946&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21867429%26dopt%3DAbstract Authors: Kirsch DG Abstract The laboratory mouse has been used for many decades as a model system for radiation research. Recent advances in genetic engineering now allow scientists to delete genes in specific cell types at different stages of development. The ability to manipulate genes in the mouse with spatial and temporal control opens new opportunities to investigate the role of genes in regulating the response of normal tissues and tumors to radiation. Currently, we are using the Cre-loxP system to delete genes, such as p53, in a cell-type specific manner in mice to study mechanisms of acute radiation injury and late effects of radiation. Our results demonstrate that p53 is required in the gastrointestinal (GI) epithelium to prevent radiation-induced GI syndrome and in endoth... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174946 Tue, 30 Aug 2011 07:52:29 +0100 5174946 http://www.medworm.com/index.php?rid=5174945&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21867430%26dopt%3DAbstract Authors: Sieber F, Muir SA, Cohen EP, Fish BL, Mäder M, Schock AM, Althouse BJ, Moulder JE Abstract We recently reported that daily dietary supplementation with 100 µg selenium (a dose exceeding a rat's nutritional requirement by about 33-fold) initiated immediately after total-body irradiation (TBI) and maintained for 21 weeks mitigates radiation nephropathy in a rat model as indicated by blood urea nitrogen (BUN) levels and histopathological criteria (Radiat Res. 2009; 17:368-73). In this follow-up study, we explored the risks and benefits of delaying the onset of supplementation, shortening periods of supplementation, and escalating selenium supplementation beyond 100 µg/day. Supplementation with 200 µg selenium/day (as selenite or seleno-l-methionine) substantially impr... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174945 Tue, 30 Aug 2011 07:52:23 +0100 5174945 http://www.medworm.com/index.php?rid=5174944&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21867431%26dopt%3DAbstract Authors: Glazer PM, Le QT, Bristow R, Helleday T, Pelroy R, Bernhard EJ PMID: 21867431 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174944 Tue, 30 Aug 2011 07:52:17 +0100 5174944 http://www.medworm.com/index.php?rid=5174948&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21861763%26dopt%3DAbstract Authors: Young EF, Smilenov LB Abstract The relative radiation sensitivities of the various compartments of the heart are poorly characterized. Cardiac fibrosis is a common side effect of radiotherapy, suggesting that endothelial barrier function is an important factor in radiation-induced pathology. We employed Electric Cell Substrate Impedance Sensing (ECIS) to assess cytoskeletal rearrangement, permeability changes and endothelial barrier function changes in response to radiation in studies of human coronary arterial endothelial cells (HCAECs). A 5-Gy dose of γ radiation resulted in a significant sixfold transient decrease in transmonolayer resistance 3 h postirradiation (P = 0.001). This decrease in resistance coincided with changes in fluorescent tracer flux (P = 0.05) and di... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174948 Mon, 22 Aug 2011 23:00:00 +0100 5174948 http://www.medworm.com/index.php?rid=5174951&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21859325%26dopt%3DAbstract Authors: Slaba TC, Blattnig SR, Clowdsley MS Abstract The radiation environment on the Moon includes albedo neutrons produced by primary particles interacting with the lunar surface. In this work, HZETRN2010 is used to calculate the albedo neutron contribution to effective dose as a function of shielding thickness for four different space radiation environments and to determine to what extent various factors affect such estimates. First, albedo neutron spectra computed with HZETRN2010 are compared to Monte Carlo results in various radiation environments. Next, the impact of lunar regolith composition on the albedo neutron spectrum is examined, and the variation on effective dose caused by neutron fluence-to-effective dose conversion coefficients is studied. A methodology for comput... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174951 Sun, 21 Aug 2011 23:00:00 +0100 5174951 http://www.medworm.com/index.php?rid=5174950&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21859326%26dopt%3DAbstract In conclusion, using total doses, patterns of dose distribution, and dose rates that are compatible with potential astronaut exposure to SPE radiation, animals experienced significant toxicities that were qualitatively different from toxicities previously reported in pigs for homogeneously delivered radiation at similar doses. PMID: 21859326 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174950 Sun, 21 Aug 2011 23:00:00 +0100 5174950 http://www.medworm.com/index.php?rid=5174949&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21859327%26dopt%3DAbstract We report here on the changes in bone mass and strength in mice 7-14 days after abdominal irradiation. Male C57BL/6 mice of 10-12 weeks of age were given a single-dose (0, 5, 10, 15 or 20 Gy) or fractionated (3 Gy × 2 per day × 7.5 days) X ray to the abdomen and monitored daily for up to 14 days. A decrease in the serum bone formation marker and ex vivo osteoblast differentiation was detected 7 days after a single dose of radiation, with little change in the serum bone resorption marker and ex vivo osteoclast formation. A single dose of radiation elicited a loss of bone mineral density (BMD) within 14 days of irradiation. The BMD loss was up to 4.1% in the whole skeleton, 7.3% in tibia, and 7.7% in the femur. Fractionated abdominal irradiation induced similar extents of BMD loss 10 days ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174949 Sun, 21 Aug 2011 23:00:00 +0100 5174949 http://www.medworm.com/index.php?rid=5174954&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21854211%26dopt%3DAbstract Authors: Jourdan MM, Lopez A, Olasz EB, Duncan NE, Demara M, Kittipongdaja W, Fish BL, Mäder M, Schock A, Morrow NV, Semenenko V, Baker JE, Moulder JE, Lazarova Z Abstract Skin exposure to ionizing radiation affects the normal wound healing process and greatly impacts the prognosis of affected individuals. We investigated the effect of ionizing radiation on wound healing in a rat model of combined radiation and wound skin injury. Using a soft X-ray beam, a single dose of ionizing radiation (10-40 Gy) was delivered to the skin without significant exposure to internal organs. At 1 h postirradiation, two skin wounds were made on the back of each rat. Control and experimental animals were euthanized at 3, 7, 14, 21 and 30 days postirradiation. The wound areas were measured, and tissue... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174954 Thu, 18 Aug 2011 23:00:00 +0100 5174954 http://www.medworm.com/index.php?rid=5174953&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21854212%26dopt%3DAbstract We report here the results of studies on the functional roles of miRNAs in the radiation response in immortalized and primary endothelial cells. Global suppression of miRNA expression was achieved through downregulation of Argonaut 2 (AGO2) or DICER proteins using RNAi. The reductions in either DICER or AGO2 led to increased cell death after irradiation, indicating a prosurvival function of miRNAs. Furthermore, while cell cycle checkpoint activation and apoptosis were compromised, DNA double-strand break repair was not affected by the lack of miRNAs. The differential sensitivity of these pathways implies the independent activation of the two response pathways rather than a concerted DNA damage response. The miRNAs that were changed after 2.5 Gy irradiation were identified by TaqMan-based l... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174953 Thu, 18 Aug 2011 23:00:00 +0100 5174953 http://www.medworm.com/index.php?rid=5174952&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21854213%26dopt%3DAbstract Authors: Tian J, Zhao W, Tian S, Slater JM, Deng Z, Gridley DS Abstract The goal of this study was to compare the effects of acute 2 Gy irradiation with photons (0.8 Gy/min) or protons (0.9 Gy/min), both with and without pre-exposure to low-dose/low-dose-rate γ rays (0.01 Gy at 0.03 cGy/h), on 84 genes involved in stem cell differentiation or regulation in mouse lungs on days 21 and 56. Genes with a ≥1.5-fold difference in expression and P < 0.05 compared to 0 Gy controls are emphasized. Two proteins specific for lung stem cells/progenitors responsible for local tissue repair were also compared. Overall, striking differences were present between protons and photons in modulating the genes. More genes were affected by protons than by photons (22 compared to 2 and 6 compared to... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5174952 Thu, 18 Aug 2011 23:00:00 +0100 5174952 http://www.medworm.com/index.php?rid=5141101&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21823971%26dopt%3DAbstract Authors: Kleinerman R, Mabuchi K, Linet M PMID: 21823971 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5141101 Sun, 07 Aug 2011 23:00:00 +0100 5141101 http://www.medworm.com/index.php?rid=5141100&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21823972%26dopt%3DAbstract Authors: Stewart RD, Yu VK, Georgakilas AG, Koumenis C, Park JH, Carlson DJ Abstract Abstract Radiation quality and cellular oxygen concentration have a substantial impact on DNA damage, reproductive cell death and, ultimately, the potential efficacy of radiation therapy for the treatment of cancer. To better understand and quantify the effects of radiation quality and oxygen on the induction of clustered DNA lesions, we have now extended the Monte Carlo Damage Simulation (MCDS) to account for reductions in the initial lesion yield arising from enhanced chemical repair of DNA radicals under hypoxic conditions. The kinetic energy range and types of particles considered in the MCDS have also been expanded to include charged particles up to and including (56)Fe ions. The induction of ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5141100 Sun, 07 Aug 2011 23:00:00 +0100 5141100 http://www.medworm.com/index.php?rid=5141099&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21823973%26dopt%3DAbstract Authors: de González AB, Brenner A, Hartge P, Lee C, Morton L, Rajaraman P PMID: 21823973 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5141099 Sun, 07 Aug 2011 23:00:00 +0100 5141099 http://www.medworm.com/index.php?rid=5141098&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21823974%26dopt%3DAbstract In this study we analyzed the ESR signal of alanine dosimeters with gadolinium exposed to 6 MV linear accelerator photons. We observed that the addition of gadolinium brings about an improvement in the sensitivity to photons because of its high atomic number. The experimental data indicated that the addition of gadolinium increases the sensitivity of the alanine to 6 MV photons. This enhancement was better observed at high gadolinium concentrations for which the tissue equivalence is heavily reduced. However, information about the irradiation setup and of the radiation beam features allowed us to correct for this difference. Monte Carlo simulations were carried out to obtain information on the expected effect of the addition of gadolinium on the dose absorbed by the alanine molecules insid... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5141098 Sun, 07 Aug 2011 23:00:00 +0100 5141098 http://www.medworm.com/index.php?rid=5141097&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21823975%26dopt%3DAbstract Authors: Sadetzki S, Chetrit A, Mandelzweig L, Nahon D, Freedman L, Susser E, Gross R Abstract Abstract While the association between exposure to ionizing radiation and cancer is well established, its association with schizophrenia is unclear. The aim of our study was to assess risk of schizophrenia after childhood exposure to ionizing radiation to the head (mean dose: 1.5 Gy).The study population included an exposed group of 10,834 individuals irradiated during childhood for treatment of tinea capitis in the 1950s and two unexposed comparison groups of 5392 siblings and 10,834 subjects derived from the National Population Registry individually matched to the exposed group by age, sex (when possible), country of birth, and year of immigration to Israel. These groups were followed f... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5141097 Sun, 07 Aug 2011 23:00:00 +0100 5141097 http://www.medworm.com/index.php?rid=5141096&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21823976%26dopt%3DAbstract Authors: Raber J, Rosi S, Chakraborti A, Fishman K, Dayger C, Davis MJ, Villasana L, Fike JR Abstract Abstract Ionizing radiation reduces the numbers of neurons expressing activity-regulated cytoskeleton-associated protein (Arc) in the hippocampal dentate gyrus (DG). It is currently unclear if that change relates to cognitive function. We assessed the effects of 1 Gy of head-only (56)Fe-particle irradiation on hippocampus-dependent and hippocampus-independent fear conditioning and determined how those changes related to Arc expression within the DG. Irradiated mice that did not receive tone-shock pairings on day 1 showed less freezing in the same context on a second day and a lower fraction of Arc-expressing neurons in the free (lower) blade of the DG than sham-irradiated mice. Tho... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5141096 Sun, 07 Aug 2011 23:00:00 +0100 5141096 http://www.medworm.com/index.php?rid=5097440&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21797794%26dopt%3DAbstract Authors: Dynlacht JR PMID: 21797794 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5097440 Sun, 31 Jul 2011 23:00:00 +0100 5097440 http://www.medworm.com/index.php?rid=5097458&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21797665%26dopt%3DAbstract Authors: Du G, Drexler GA, Friedland W, Greubel C, Hable V, Krücken R, Kugler A, Tonelli L, Friedl AA, Dollinger G High-linear energy transfer (LET) ion irradiation of cell nuclei induces complex and severe DNA lesions, and foci of repair proteins are formed densely along the ion trajectory. To efficiently discriminate the densely distributed/overlapping foci along the ion trajectory, a focus recognition algorithm called FociPicker3D based on a local fraction thresholding technique was developed. We analyzed high-resolution 3D immunofluorescence microscopic focus images and obtained the kinetics and spatial development of γ-H2AX, 53BP1 and phospho-NBS1 foci in BJ1-hTERT cells irradiated with 55 MeV carbon ions and compared the results with the dynamics of double-strand break (DSB) d... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5097458 Tue, 26 Jul 2011 23:00:00 +0100 5097458 http://www.medworm.com/index.php?rid=5097565&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21787181%26dopt%3DAbstract Authors: Moravan MJ, Olschowka JA, Williams JP, O'Banion MK Radiotherapy is commonly employed to treat cancers of the head and neck and is increasingly used to treat other central nervous system (CNS) disorders. Exceeding the radiation tolerance of normal CNS tissues can result in sequelae contributing to patient morbidity and mortality. Animal studies and clinical experience suggest that neuroinflammation plays a role in the etiology of these effects; however, detailed characterization of this response has been lacking. Therefore, a dose-time investigation of the neuroinflammatory response after single-dose cranial irradiation was performed using C57BL/6 mice. Consistent with previous reports, cranial irradiation resulted in multiphasic inflammatory changes exemplified by increased tr... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5097565 Sun, 24 Jul 2011 23:00:00 +0100 5097565 http://www.medworm.com/index.php?rid=5097509&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21787182%26dopt%3DAbstract Authors: Grosche B, Lackland DT, Land CE, Simon SL, Apsalikov KN, Bauer S, Pivina LM, Gusev BI The data on risk of mortality from cardiovascular disease due to radiation exposure at low or medium doses are inconsistent. This paper reports an analysis of the Semipalatinsk historical cohort exposed to radioactive fallout from nuclear testing in the vicinity of the Semipalatinsk Nuclear Test Site, Kazakhstan. The cohort study, which includes 19,545 persons of exposed and comparison villages in the Semipalatinsk region, had been set up in the 1960s and comprises 582,656 person-years of follow-up between 1960 and 1999. A dosimetric approach developed by the U.S. National Cancer Institute (NCI) has been used. Radiation dose estimates in this cohort range from 0 to 630 mGy (whole-body extern... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5097509 Sun, 24 Jul 2011 23:00:00 +0100 5097509 http://www.medworm.com/index.php?rid=5097491&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21787183%26dopt%3DAbstract This study investigated the effect of high atomic number, high-energy (HZE) iron-ion radiation on vascular and endothelial function as a model of space radiation. Rats were exposed to a single whole-body dose of iron-ion radiation at doses of 0, 0.5 and 1 Gy. In vivo aortic stiffness and ex vivo aortic tension responses were measured 6 and 8 months after exposure as indicators of chronic vascular injury. Rats exposed to 1 Gy iron ions demonstrated significantly increased aortic stiffness, as measured by pulse wave velocity. Aortic rings from irradiated rats exhibited impaired endothelial-dependent relaxation consistent with endothelial dysfunction. Acute xanthine oxidase (XO) inhibition or reactive oxygen species (ROS) scavenging restored endothelial-dependent responses to normal. In ad... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5097491 Sun, 24 Jul 2011 23:00:00 +0100 5097491 http://www.medworm.com/index.php?rid=5051381&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21756082%26dopt%3DAbstract In this study we investigated whether the salvage dNTP supply pathway facilitates DNA damage repair, promoting cell survival, when pharmacological inhibition of RNR by 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, NSC no. 663249) impairs the de novo pathway. Human cervical cancer cells were subjected to radiation with or without 3-AP under medium deoxynucleoside concentrations of 0, 0.05, 0.5 and 5.0 µM. Efficacy of DNA damage repair was assessed by γ-H2AX flow cytometry and focus counts, by single cell electrophoresis (Comet assay), and by caspase 3 cleavage assay as a marker of treatment-induced apoptosis. Cell survival was assessed by colony formation. We found that deoxyribonucleotide salvage facilitates DNA repair during RNR inhibition by 3-AP and that salvage reduces ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051381 Wed, 13 Jul 2011 23:00:00 +0100 5051381 http://www.medworm.com/index.php?rid=5051380&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21756083%26dopt%3DAbstract Authors: Takam R, Bezak E, Marcu LG, Yeoh E Determination and understanding of out-of-field neutron and photon doses in accelerator-based radiotherapy is an important issue since linear accelerators operating at high energies (>10 MV) produce secondary radiations that irradiate parts of the patient's anatomy distal to the target region, potentially resulting in detrimental health effects. This paper provides a compilation of data (technical and clinical) reported in the literature on the measurement and Monte Carlo simulations of peripheral neutron and photon doses produced from high-energy medical linear accelerators and the reported risk and/or incidence of second primary cancer of tissues distal to the target volume. Information in the tables facilitates easier identification of... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051380 Wed, 13 Jul 2011 23:00:00 +0100 5051380 http://www.medworm.com/index.php?rid=5051385&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21740250%26dopt%3DAbstract Authors: Sieber F, Muir SA, Cohen EP, Fish BL, Mäder M, Schock AM, Althouse BJ, Moulder JE We recently reported that daily dietary supplementation with 100 µg selenium (a dose exceeding a rat's nutritional requirement by about 33-fold) initiated immediately after total-body irradiation (TBI) and maintained for 21 weeks mitigates radiation nephropathy in a rat model as indicated by blood urea nitrogen (BUN) levels and histopathological criteria (Radiat Res. 2009; 17:368-73). In this follow-up study, we explored the risks and benefits of delaying the onset of supplementation, shortening periods of supplementation, and escalating selenium supplementation beyond 100 µg/day. Supplementation with 200 µg selenium/day (as selenite or seleno-l-methionine) substantially improved the miti... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051385 Thu, 07 Jul 2011 23:00:00 +0100 5051385 http://www.medworm.com/index.php?rid=5051384&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21740251%26dopt%3DAbstract Authors: Glazer PM, Grandis J, Powell SN, Brown JM, Helleday T, Bristow R, Powis G, Hill RP, Le QT, Pelroy R, Mohla S, Bernhard EJ PMID: 21740251 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051384 Thu, 07 Jul 2011 23:00:00 +0100 5051384 http://www.medworm.com/index.php?rid=5051383&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21740252%26dopt%3DAbstract Authors: Glazer PM, Le QT, Bristow R, Helleday T, Pelroy R, Bernhard EJ PMID: 21740252 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051383 Thu, 07 Jul 2011 23:00:00 +0100 5051383 http://www.medworm.com/index.php?rid=5051382&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21740253%26dopt%3DAbstract Authors: Magae J, Furukawa C, Ogata H Irradiation time and dose rate are important factors in the evaluation of radiation risk for human health. We previously proposed a novel dose-rate effect model, the modified exponential (MOE) model, which predicts that radiation risks decline exponentially as the dose rate decreases. Here we show that, during the early phase of exposure, up to 1000 h, the proliferation of cells continuously exposed to γ rays at a constant dose rate is gradually suppressed, even as the total dose increases. This trend holds for a number of cell lines including tumor cells, nontransformed fibroblasts and leukocytes. The accumulation of total dose by longer exposure times does not increase this suppressive effect even in cells with a defective DNA repair system, su... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051382 Thu, 07 Jul 2011 23:00:00 +0100 5051382 http://www.medworm.com/index.php?rid=5051386&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21732791%26dopt%3DAbstract In this study, the end point examined was transformation in vitro from a preneoplastic to a neoplastic phenotype. The effects of 1 GeV/n iron ions and 1 GeV/n protons alone provided strong evidence for suppression of transformation at doses ≤5 cGy. These ions were also studied in combination in so-called mixed-beam experiments. The specific protocols were a low dose (10 cGy) of protons followed after either 5-15 min (immediate) or 16-24 h (delayed) by 1 Gy of iron ions and a low dose (10 cGy) of iron ions followed after either 5-15 min or 16-24 h by 1 Gy of protons. Within experimental error the results indicated an additive interaction under all conditions with no evidence of an adaptive response, with the one possible exception of 10 cGy iron ions followed immediately by 1�... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5051386 Tue, 05 Jul 2011 23:00:00 +0100 5051386 http://www.medworm.com/index.php?rid=5000837&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21718103%26dopt%3DAbstract This study examined whether ionizing radiation exposure is associated with levels of serum hormones and other markers that may mediate radiation-associated breast cancer risk. Serum samples were measured from cancer-free women who attended biennial health examinations with a wide range of past radiation exposure levels (N  =  412, ages 26-79). The women were selected as controls for separate case-control studies from a cohort of A-bomb survivors. Outcome measures included serum levels of total estradiol, bioavailable estradiol, testosterone, progesterone, prolactin, insulin-like growth factor-1 (IGF1), insulin-like growth factor-binding protein 3 (IGFBP-3), and ferritin. Relationships were assessed using repeated-measures regression models fitted with generalized estimating equations. ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000837 Wed, 29 Jun 2011 23:00:00 +0100 5000837 http://www.medworm.com/index.php?rid=5000836&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21718104%26dopt%3DAbstract Authors: Ponnaiya B, Suzuki M, Tsuruoka C, Uchihori Y, Wei Y, Hei TK There is increasing evidence that two of the biological effects associated with low-dose ionizing radiation, genomic instability and bystander responses, may be linked. To verify and validate the link between the two phenomena, the ability of Si490 ions (high-energy particles associated with radiation risk in space) to induce bystander responses and chromosomal instability in human bronchial epithelial (HBEC-3kt) cells was investigated. These studies were conducted at both the population and single cell level in irradiated and nonirradiated bystander cells receiving medium from the irradiated cultures. At the general population level, transfer of medium from silicon-ion (Si490)-irradiated cultures (at doses of 0.073 ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000836 Wed, 29 Jun 2011 23:00:00 +0100 5000836 http://www.medworm.com/index.php?rid=5000835&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21718105%26dopt%3DAbstract Authors: Nomura T, Li XH, Ogata H, Sakai K, Kondo T, Takano Y, Magae J It has been proposed that the development of diabetic nephropathy is caused in large part by oxidative stress. We previously showed that continuous exposure of mice to low-dose-rate γ radiation enhances antioxidant activity. Here, we studied the ameliorative effect of continuous whole-body irradiation with low-dose-rate γ rays on diabetic nephropathy. Ten-week-old female db/db mice, an experimental model for type II diabetes, were irradiated with low-dose-rate γ rays from 10 weeks of age throughout their lives. Nephropathy was studied by histological observation and biochemical analysis of serum and urine. Antioxidant activities in kidneys were determined biochemically. Continuous low-dose-rate γ radiation sign... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000835 Wed, 29 Jun 2011 23:00:00 +0100 5000835 http://www.medworm.com/index.php?rid=5000838&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21714633%26dopt%3DAbstract Authors: Leuraud K, Schnelzer M, Tomasek L, Hunter N, Timarche M, Grosche B, Kreuzer M, Laurier D A combined analysis of three case-control studies nested in three European uranium miner cohorts was performed to study the joint effects of radon exposure and smoking on lung cancer death risk. Occupational history and exposure data were available from the cohorts. Smoking information was reconstructed using self-administered questionnaires and occupational medical archives. Linear excess relative risk models adjusted for smoking were used to estimate the lung cancer risk associated with radon exposure. The study includes 1046 lung cancer cases and 2492 controls with detailed radon exposure data and smoking status. The ERR/WLM adjusted for smoking is equal to 0.008 (95% CI: 0.004-0.014). ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000838 Tue, 28 Jun 2011 23:00:00 +0100 5000838 http://www.medworm.com/index.php?rid=5000839&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21699368%26dopt%3DAbstract Authors: Dynlacht JR, Batuello CN, Lopez JT, Kim KK, Turchi JJ Thermal radiosensitization is believed to be mediated by an inhibition of double-strand break (DSB) repair, but the exact mechanism of radiosensitization remains to be elucidated. Previously, we demonstrated that proteins of the Mre11/Rad50/Nbs1 complex (MRN) translocate from the nucleus to the cytoplasm in cells have that been heated or heated and then irradiated; this finding led us to propose that heat radiosensitization was due at least in part to translocation of MRN. In the current study, we used leptomycin B to inhibit MRN translocation in heated, irradiated cells, but we found that heat radiosensitization was not altered. Thus enhanced radiosensitivity was not attributed to translocation of MRN proteins. To determin... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000839 Wed, 22 Jun 2011 23:00:00 +0100 5000839 http://www.medworm.com/index.php?rid=5000845&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21692651%26dopt%3DAbstract Authors: Yang M, Kim JS, Son Y, Kim J, Kim JY, Kim SH, Kim JC, Shin T, Moon C This in vitro study compared the detrimental effect and relative biological effectiveness (RBE) of high-linear energy transfer (LET) fast neutrons on rat immature hippocampal cultured cells with those of low-LET γ rays. Immature hippocampal cells were exposed to fast neutrons or γ rays. Cytotoxicity and cell viability were analyzed using a lactate dehydrogenase (LDH)-release assay and a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, respectively. The cytotoxicity and cell viability with fast neutrons or γ rays varied in a dose-dependent pattern. In the LDH release and MTT assay indices, the RBEs of fast neutrons were approximately 2.35 and 2.42, respectively. Fast neutrons marke... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000845 Mon, 20 Jun 2011 23:00:00 +0100 5000845 http://www.medworm.com/index.php?rid=5000844&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21692652%26dopt%3DAbstract Authors: Puncher M, Birchall A, Bull RK In a recent epidemiological study, Bayesian uncertainties on lung doses have been calculated to determine lung cancer risk from occupational exposures to plutonium. These calculations used a revised version of the Human Respiratory Tract Model (HRTM) published by the ICRP. In addition to the Bayesian analyses, which give probability distributions of doses, point estimates of doses (single estimates without uncertainty) were also provided for that study using the existing HRTM as it is described in ICRP Publication 66; these are to be used in a preliminary analysis of risk. To infer the differences between the point estimates and Bayesian uncertainty analyses, this paper applies the methodology to former workers of the United Kingdom Atomic Energy... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000844 Mon, 20 Jun 2011 23:00:00 +0100 5000844 http://www.medworm.com/index.php?rid=5000843&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21692653%26dopt%3DAbstract Authors: Schütz C, Brochhausen C, Altieri S, Bartholomew K, Bortolussi S, Enzmann F, Gabel D, Hampel G, Kirkpatrick CJ, Kratz JV, Minouchehr S, Schmidberger H, Otto G The typical primary malignancies of the liver are hepatocellular carcinoma and cholangiocarcinoma, whereas colorectal liver metastases are the most frequently occurring secondary tumors. In many cases, only palliative treatment is possible. Boron neutron capture therapy (BNCT) represents a technique that potentially destroys tumor tissue selectively by use of externally induced, locally confined secondary particle irradiation. In 2001 and 2003, BNCT was applied to two patients with colorectal liver metastases in Pavia, Italy. To scrutinize the rationale of BNCT, a clinical pilot study on patients with colorectal liver me... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000843 Mon, 20 Jun 2011 23:00:00 +0100 5000843 http://www.medworm.com/index.php?rid=5000842&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21692654%26dopt%3DAbstract Authors: Yamauchi T, Adachi S, Yasuda I, Nakashima M, Kawaguchi J, Nishii Y, Yoshioka T, Okano Y, Hirose Y, Kozawa O, Moriwaki H Epidermal growth factor receptor (EGFR) is overexpressed in human pancreatic cancer and is one of the clinical targets in its treatment. In the present study we investigated the mechanism underlying ultraviolet C (UVC)-radiation-induced cell growth inhibition and downregulation of EGFR in human pancreatic cancer cells (Panc1 and KP3). The cell proliferation assay indicated that Panc1 and KP3 cells were more sensitive to UVC radiation, and their growth was significantly inhibited compared to cells of the normal human pancreatic epithelial cell line, PE. Although EGFR levels was extremely low in PE cells, EGFR were highly overexpressed in Panc1 and KP3 cells, a... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000842 Mon, 20 Jun 2011 23:00:00 +0100 5000842 http://www.medworm.com/index.php?rid=5000841&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21692655%26dopt%3DAbstract In this study, we identified and analyzed AML stem cells of mice with radiation-induced AML. The AML stem cells were identified by transplanting 100 bone marrow cells from mice with radiation-induced AML. We injected 100 cells of each of seven cell populations corresponding to different stages of hematopoietic cell differentiation and compared the latencies of AMLs induced in recipient mice. The identified radiation-induced AML stem cells frequently displayed similarities in both CD antigen and gene expression profiles with normal common myeloid progenitors. The number of common myeloid progenitor-like AML stem cells was significantly increased in mice with radiation-induced AML, but the progeny of common myeloid progenitors was decreased. In addition, analysis of radiation effects on the ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000841 Mon, 20 Jun 2011 23:00:00 +0100 5000841 http://www.medworm.com/index.php?rid=5000840&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21692656%26dopt%3DAbstract Authors: Nakayama M, Kaida A, Deguchi S, Sakaguchi K, Miura M The mitotic shake-off method revealed the remarkable variation of radiosensitivity of HeLa cells during the cell cycle: M phase shows the greatest radiosensitivity and late S phase the greatest radioresistance. This method harvests all M-phase cells with a round shape, making it impossible to further subdivide M-phase cells. Recently, the fluorescence ubiquitination-based cell cycle indicator (Fucci) was developed; this system basically causes cells in G(1) to emit red fluorescence and other cells to emit green fluorescence. Because the green fluorescence rapidly disappears at late M phase, two-dimensional flow cytometry analysis can usually detect a green(high)/red(low) fraction including S-, G(2)- and early M-phase cells b... Radiation Research journals http://www.medworm.com/rss/comments.php?id=5000840 Mon, 20 Jun 2011 23:00:00 +0100 5000840 http://www.medworm.com/index.php?rid=4955089&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21663393%26dopt%3DAbstract Authors: Mendonca MS, Chin-Sinex H, Dhaemers R, Mead LE, Yoder MC, Ingram DA Endothelial colony-forming cells (ECFCs) are endothelial progenitor cells that circulate at low concentration in human umbilical cord and adult peripheral blood and are largely resident in blood vessels. ECFCs not only appear to be critical for normal vascular homeostasis and repair but may also contribute to tumor angiogenesis and response to therapy. To begin to characterize the potential role of ECFCs during the treatment of tumors in children and adults with radiation, we characterized the X-ray sensitivity of cord and adult blood-derived ECFCs. We found both cord blood and adult ECFCs to be highly radiation sensitive (3 Gy resulted in >90% killing without induction of apoptosis). The X-ray survival cu... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4955089 Thu, 09 Jun 2011 23:00:00 +0100 4955089 http://www.medworm.com/index.php?rid=4955088&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21663394%26dopt%3DAbstract Authors: Li B, Torossian A, Li W, Schleicher S, Niu K, Giacalone NJ, Kim SJ, Chen H, Gonzalez A, Moretti L, Lu B Lung cancer is the leading cause of cancer-related death in the United States despite recent advances in our understanding of this challenging disease. An animal model for high-throughput screening of therapeutic agents for advanced lung cancer could help promote the development of more successful treatment interventions. To develop our orthotopic lung cancer model, luciferase-expressing A549 cancer cells were injected into the mediastinum of athymic nude mice. To determine whether the model would allow easy monitoring of response to therapeutic interventions, tumors were treated with 30 mg/kg Paclitaxel or were irradiated with 5 fractions of 2 Gy, and tumor burden was mon... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4955088 Thu, 09 Jun 2011 23:00:00 +0100 4955088 http://www.medworm.com/index.php?rid=4955087&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21663395%26dopt%3DAbstract Authors: Shukla J, Khan NM, Thakur VS, Poduval TB Our earlier studies demonstrated the ability of l-arginine (l-Arg) to reverse radiation-induced immune dysfunction. The aim of the present study was to investigate cardiac dysfunction up to 24 h after 2 Gy of total-body irradiation (TBI) and its mitigation by l-Arg. The current studies also explore the association of radiation-induced inflammation and electrocardiographic (ECG) abnormalities. TBI-induced cardiac iNOS and kinin B1 R, changes in the ECG profile like bradycardia, increased RR interval, ST elevation and increased QRS duration at 4 h and 24 h after TBI. TBI with 2 Gy induced inflammatory responses in spleen and cardiac tissue. l-Arg administered 2 h after TBI (TBI+l-Arg) mitigated the entire inflammatory response and E... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4955087 Thu, 09 Jun 2011 23:00:00 +0100 4955087 http://www.medworm.com/index.php?rid=4955086&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21663396%26dopt%3DAbstract Authors: Abdelrazzak AB, Stevens DL, Bauer G, O'Neill P, Hill MA An important stage in tumorigenesis is the ability of precancerous cells to escape natural anticancer signals. Apoptosis can be selectively induced in transformed cells by neighboring normal cells through cytokine and ROS/RNS signaling. The intercellular induction of apoptosis in transformed cells has previously been found to be enhanced after exposure of the normal cells to very low doses of both low- and high-LET ionizing radiation. Low-LET ultrasoft X rays with a range of irradiation masks were used to vary both the dose to the cells and the percentage of normal cells irradiated. The results obtained were compared with those after α-particle irradiation. The intercellular induction of apoptosis in nonirradiated, src-t... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4955086 Thu, 09 Jun 2011 23:00:00 +0100 4955086 http://www.medworm.com/index.php?rid=4955085&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21663397%26dopt%3DAbstract This study extends earlier findings of the authors demonstrating that meloxicam, a selective inhibitor of cyclooxygenase 2, supports hematopoietic recovery in sublethally irradiated mice and is radioprotective when given before irradiation. We report here that when meloxicam was administered in a single dose 1 h after a lethal 9-Gy whole-body dose, an increased 30-day survival was achieved. Additional studies showed that administration of meloxicam 24 h after lethal irradiation is ineffective and its repeated administration deleterious. Possible mechanisms of the therapeutic effects of meloxicam administered early after irradiation are discussed. PMID: 21663397 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4955085 Thu, 09 Jun 2011 23:00:00 +0100 4955085 http://www.medworm.com/index.php?rid=4955084&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21663398%26dopt%3DAbstract Authors: Fukumoto R, Kiang JG Exposure to ionizing radiation induces p53, and its inhibition improves mouse survival. We tested the effect of 17-dimethylamino-ethylamino-17-demethoxygeldanamycin (17-DMAG) on p53 expression and function after radiation exposure. 17-DMAG, a heat-shock protein 90 (Hsp90) inhibitor, protects human T cells from ionizing radiation-induced apoptosis by inhibiting inducible nitric oxide synthase (iNOS) and subsequent caspase-3 activation. Using ex vivo human peripheral blood mononuclear cells, we found that ionizing radiation increased p53 accumulation, acute p53 phosphorylation, Bax expression and caspase-3/7 activation in a radiation dose- and time postirradiation-dependent manner. 17-DMAG inhibited these increases in a concentration-dependent manner (IC(50)... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4955084 Thu, 09 Jun 2011 23:00:00 +0100 4955084 http://www.medworm.com/index.php?rid=4905726&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631285%26dopt%3DAbstract Authors: Wang XD, He SY, Yang DZ, Gu PF Abstract Space radiation damage in ZnO induced by subthreshold electrons was studied through reflectance spectra, electron paramagnetic resonance, and photoluminescence. Owing to the vacuum freezing treatment, perturbed singly ionized zinc vacancies (V'(Zn)(-)), chemisorbed species, and electrons in the conduction band and/or bound to shallow donor levels were observed. V'(Zn)(-) is due to the ionization and the ionization-induced diffusion processes and is most likely responsible for the 420-nm absorption band. These results also supports that the green luminescence in ZnO is related to zinc vacancies. PMID: 21631285 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905726 Tue, 31 May 2011 23:00:00 +0100 4905726 http://www.medworm.com/index.php?rid=4905725&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631286%26dopt%3DAbstract Authors: Blyth BJ, Sykes PJ Abstract The term radiation-induced bystander effect is used to describe radiation-induced biological changes that manifest in unirradiated cells remaining within an irradiated cell population. Despite their failure to fit into the framework of classical radiobiology, radiation-induced bystander effects have entered the mainstream and have become established in the radiobiology vocabulary as a bona fide radiation response. However, there is still no consensus on a precise definition of radiation-induced bystander effects, which currently encompasses a number of distinct signal-mediated effects. These effects are classified here into three classes: bystander effects, abscopal effects and cohort effects. In this review, the data have been evaluated to define, ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905725 Tue, 31 May 2011 23:00:00 +0100 4905725 http://www.medworm.com/index.php?rid=4905724&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631287%26dopt%3DAbstract Authors: Gómez JA, Marques T, Kinoshita A, Belmonte G, Nicolucci P, Baffa O Abstract Using an experimental model and PENELOPE Monte Carlo simulations, the effects of resin and amalgam on the absorbed doses in tooth enamel were studied to evaluate the feasibility of using restored teeth in electron spin resonance (ESR) dose reconstruction. The model consisted of a phantom containing a plate of these restorative materials placed between powered enamel layers exposed to X rays and a (60)Co beam. The experimental results and simulations agreed, showing that the attenuation produced by amalgam and resin with a thickness of 1, 2, and 4 mm is similar to that produced by the enamel itself in the case of the radiation sources employed. For X rays and (60)Co γ radiation the attenuation reache... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905724 Tue, 31 May 2011 23:00:00 +0100 4905724 http://www.medworm.com/index.php?rid=4905723&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631288%26dopt%3DAbstract Authors: Schmid TE, Oestreicher U, Molls M, Schmid E Abstract There is rapidly increasing information on the issue of three-dimensional nuclear architecture, according to which chromosomes are organized in localized territories and chromosome arms in exclusive domains within a given territory. The aim of the present study was to investigate the impact of different cell exposure conditions on cytogenetic damage induced by high-LET radiation. To this end the yield ratio of dicentrics to centric rings (F value) induced by (241)Am α particles was analyzed in monolayer cultures of human lymphocytes that were either settled or attached to foils, simulating a rounded or spread out cellular geometry, respectively. Monolayers were exposed in special irradiation chambers to 0.1 and 1.0 Gy and ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905723 Tue, 31 May 2011 23:00:00 +0100 4905723 http://www.medworm.com/index.php?rid=4905722&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631289%26dopt%3DAbstract Authors: Seideman JH, Stancevic B, Rotolo JA, McDevitt MR, Howell RW, Kolesnick RN, Scheinberg DA Abstract The sphingomyelin pathway involves the enzymatic cleavage of sphingomyelin to produce ceramide, a second messenger that serves as a key mediator in the rapid apoptotic response to various cell stressors. Low-linear energy transfer (LET) γ radiation can initiate this pathway, independent of DNA damage, via the cell membrane. Whether short-ranged, high-LET α particles, which are of interest as potent environmental carcinogens, radiotherapies and potential components of dirty bombs, can act through this mechanism to signal apoptosis is unknown. Here we show that irradiation of Jurkat cells with α particles emitted by the (225)Ac-DOTA-anti-CD3 IgG antibody construct results in dose... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905722 Tue, 31 May 2011 23:00:00 +0100 4905722 http://www.medworm.com/index.php?rid=4905721&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631290%26dopt%3DAbstract Authors: Fang J, Ma I, Allalunis-Turner J Abstract Cytoglobin is a recently identified vertebrate globin whose functions include scavenging reactive oxygen and nitrosative species. In tumor cells, CYGB may function as a tumor suppressor gene. Here we show that knockdown of cytoglobin expression can sensitize human glioma cells to oxidative stress induced by chemical inhibitors of the electron transport chain and as well can increase cellular radiosensitivity. When treated with antimycin A, an inhibitor of the mitochondrial electron transport chain, cytoglobin-deficient cells showed significantly higher H(2)O(2) levels, whereas H(2)O(2) levels were significantly reduced in cytoglobin-overexpressing cells. In addition, cytoglobin knockdown significantly decreased the doubling time of gli... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905721 Tue, 31 May 2011 23:00:00 +0100 4905721 http://www.medworm.com/index.php?rid=4905720&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21631291%26dopt%3DAbstract Authors: Shi WQ, Fu HY, Bounds PL, Muroya Y, Lin MZ, Katsumura Y, Zhao YL, Chai ZF Abstract 3-Nitrotyrosine has been reported as an important biomarker of oxidative stress that may play a role in a variety of diseases. In this work, transient UV-visible absorption spectra and kinetics observed during the reaction of the hydrated electron, e(aq)(-), with 3-nitrotyrosine and derivatives thereof were investigated. The absorption spectra show characteristics of aromatic nitro anion radicals. The absorptivity of radical anion product at 300 nm is estimated to be (1.0 ± 0.2) × 10(4) M(-1) cm(-1) at pH 7.3. The rate constants determined for the reaction of e(aq)(-) with 3-nitrotyrosine, N-acetyl-3-nitrotyrosine ethyl ester and glycylnitrotyrosylglycine at neutral pH - (3.0 ± 0.3) × 10... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4905720 Tue, 31 May 2011 23:00:00 +0100 4905720 http://www.medworm.com/index.php?rid=4855892&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21574861%26dopt%3DAbstract Authors: Cucinotta FA, Chappell LJ Abstract New epidemiology assessments of the life span study (LSS) of the atomic bomb survivors in Japan and of other exposed cohorts have been made by the U.S. National Academy of Sciences, the United Nations Committee on the Effects of Atomic Radiation, and the Radiation Research Effects Foundation in Japan. The National Aeronautics and Space Administration (NASA) uses a 3% risk of exposure-induced death (REID) as a basis for setting age- and gender-specific dose limits for astronauts. NASA's dose limits originate from the report of the National Council on Radiation Protection and Measurements (NCRP) in the year 2000 based on analysis of older epidemiology data. We compared the results of the recent analysis of the LSS to the earlier risk projection... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855892 Sun, 15 May 2011 23:00:00 +0100 4855892 http://www.medworm.com/index.php?rid=4855891&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21574862%26dopt%3DAbstract Authors: Mao XW, Mekonnen T, Kennedy AR, Gridley DS Abstract Changes in the expression of genes implicated in oxidative stress and in extracellular matrix (ECM) remodeling and selected protein expression profiles in mouse skin were examined after exposure to low-dose-rate or high-dose-rate photon irradiation. ICR mice received whole-body γ rays to total doses of 0, 0.25, 0.5 and 1 Gy at dose rates of 50 cGy/h or 50 cGy/min. Skin tissues were harvested for characterization at 4 h after irradiation. For oxidative stress after low-dose-rate exposure, 0.25, 0.5 and 1 Gy significantly altered 27, 23 and 25 genes, respectively, among 84 genes assessed (P < 0.05). At doses as low as 0.25 Gy, many genes responsible for regulating the production of reactive oxygen species (ROS) were s... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855891 Sun, 15 May 2011 23:00:00 +0100 4855891 http://www.medworm.com/index.php?rid=4855890&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21574863%26dopt%3DAbstract Authors: Wang T, Li F, Xu S, Bian P, Wu Y, Wu L, Yu Z Abstract The radiation-induced bystander effect has been demonstrated in whole organisms as well as in multicellular tissues in vitro and single-cell culture systems in vitro. However, the time course of bystander signaling, especially in whole organisms, is not clear. Long-distance bystander/abscopal effects in vivo in plants have been demonstrated by our group. Plant grafting is a useful experimental tool for studying the root-shoot signaling of plants. In the present study, we developed a root micro-grafting technique with young seedlings of Arabidopsis thaliana in which the bystander signaling communication of root-to-shoot could easily be stopped or started at specific times after root irradiation. Using this methodology, we de... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855890 Sun, 15 May 2011 23:00:00 +0100 4855890 http://www.medworm.com/index.php?rid=4855889&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21574864%26dopt%3DAbstract Authors: Farcy E, Voiseux C, Robbes I, Lebel JM, Fievet B Abstract In the North-Cotentin (Normandy, France), the marine environment is chronically exposed to liquid releases from the La Hague nuclear fuel recycling plant (Areva NC), resulting in a small increase in radioactivity compared to natural background. The transcriptional expression levels of stress genes were investigated in oysters exposed to ionizing radiation. Adult oysters were kept for 6 weeks in (60)Co-labeled seawater (400 Bq liter(-1)), resulting in a total dose of 6.2 mGy. Transcriptional expression of target genes was monitored by reverse-transcription quantitative polymerase chain reaction. Nine genes were selected for their sensitivity to ionizing radiation based on the literature and available DNA sequences. T... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855889 Sun, 15 May 2011 23:00:00 +0100 4855889 http://www.medworm.com/index.php?rid=4855893&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21561339%26dopt%3DAbstract We present here the first 3D measurements of the Station's radiation environment, discriminating particle trajectories and LET, made possible using the detection capability of the ALTEA-space detector. We provide evidence for a strong (factor ≈ 3) anisotropy in the inner integral LET for high-LET particles (LET > 50 keV/µm) showing a minimum along the longitudinal station axis (most shielded) and a maximum normal to it. Integrating over all measured LETs, the anisotropy is strongly reduced, showing that unstopped light ions plus the fragments produced by heavier ions approximately maintain flux/LET isotropy. This suggests that, while changing the quality of radiation, the extra shielding along the station main axis is not producing a benefit in terms of total LET. These features sho... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855893 Tue, 10 May 2011 23:00:00 +0100 4855893 http://www.medworm.com/index.php?rid=4855895&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21557666%26dopt%3DAbstract Authors: Li Q, Martinez JD Abstract HSF1 is a transcription factor that plays a key role in the response to heat stress and was previously shown by us to also be essential for importation of p53 into the nucleus. Here we extend these studies and show that loss of HSF1 renders cells more sensitive to killing by ionizing radiation. Cells that lack a functional HSF1 were unable to arrest in G(2) after exposure to ionizing radiation, suggesting that HSF1 activity was essential for activation of this cell cycle checkpoint. In addition, cells with no HSF1 showed a reduced capacity to repair radiation-induced double-stranded DNA breaks. We found that in these cells 53BP1 did not accumulate at sites of DNA damage, suggesting that HSF1 was also essential for the functioning of this DNA damage m... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855895 Mon, 09 May 2011 23:00:00 +0100 4855895 http://www.medworm.com/index.php?rid=4855894&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21557667%26dopt%3DAbstract Authors: Stisova V, Abele WH, Thompson KH, Bennett PV, Sutherland BM Abstract Solar particle events (SPEs) present a major radiation-related risk for manned exploratory missions in deep space. Within a short period the astronauts may absorb doses that engender acute effects, in addition to the risk of late effects, such as the induction of cancer. Using primary human cells, we studied clonogenic survival and the induction of neoplastic transformation after exposure to a worst case scenario SPE. We simulated such an SPE with monoenergetic protons (50, 100, 1000 MeV) delivered at a dose rate of 1.65 cGy min(-1) in a dose range from 0 to 3 Gy. For comparison, we exposed the cells to a high dose rate of 33.3 cGy min(-1). X rays (100 kVp, 8 mA, 1.7 mm Al filter) were used as a refe... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4855894 Mon, 09 May 2011 23:00:00 +0100 4855894 http://www.medworm.com/index.php?rid=4803981&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21545289%26dopt%3DAbstract Authors: Dicarlo AL, Poncz M, Cassatt DR, Shah JR, Czarniecki CW, Maidment BW PMID: 21545289 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803981 Wed, 04 May 2011 23:00:00 +0100 4803981 http://www.medworm.com/index.php?rid=4803980&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21545290%26dopt%3DAbstract Authors: Conner KR, Forbes ME, Lee WH, Lee YW, Riddle D Abstract Blockers of the renin-angiotensin-aldosterone system (RAAS) ameliorate cognitive deficits and some aspects of brain injury after whole-brain irradiation. We investigated whether treatment with the angiotensin II type 1 receptor antagonist L-158,809 at a dose that protects cognitive function after fractionated whole-brain irradiation reduced radiation-induced neuroinflammation and changes in hippocampal neurogenesis, well-characterized effects that are associated with radiation-induced brain injury. Male F344 rats received L-158,809 before, during and after a single 10-Gy dose of radiation. Expression of cytokines, angiotensin II receptors and angiotensin-converting enzyme 2 was evaluated by real-time PCR 24 h, 1 week an... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803980 Wed, 04 May 2011 23:00:00 +0100 4803980 http://www.medworm.com/index.php?rid=4803979&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21545291%26dopt%3DAbstract Authors: Dicarlo AL, Poncz M, Cassatt DR, Shah JR, Czarniecki CW, Maidment BW Abstract The events of September 11, 2001 and their aftermath increased awareness of the need to develop medical countermeasures (MCMs) to treat potential health consequences of a radiation accident or deliberate attack. The medical effects of lethal exposures to ionizing radiation have been well described and affect multiple organ systems. To date, much of the research to develop treatments for mitigation of radiation-induced hematopoietic damage has focused on amelioration of radiation-induced neutropenia, which has long been considered to be the primary factor in determining survival after an unintentional radiation exposure. Consistent with historical data, recent studies have highlighted the role that ra... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803979 Wed, 04 May 2011 23:00:00 +0100 4803979 http://www.medworm.com/index.php?rid=4803978&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21545292%26dopt%3DAbstract Authors: Mitchell JB PMID: 21545292 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803978 Wed, 04 May 2011 23:00:00 +0100 4803978 http://www.medworm.com/index.php?rid=4803977&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21545294%26dopt%3DAbstract Authors: Cherng JM, Tsai KD, Yu YW, Lin JC Abstract Glycyrrhizic acid has been shown to possess anti-inflammation, antiviral and chemoprotective activity against tumors. We evaluated the protective effects of glycyrrhizic acid in UVB-radiation-induced skin tumor formation in SKH-1 hairless mice and the early molecular biomarkers of these effects. Mice irradiated at 180 mJ/cm(2) twice per week showed 100% tumor incidence in 20 weeks. Feeding with glycyrrhizic acid prior to UVB irradiation caused delays in tumor appearance, multiplicity and size. Feeding with glycyrrhizic acid for 2 weeks before a single UVB irradiation (180 mJ/cm(2)) resulted in significant decrease in UVB-radiation-induced thymine dimer-positive cells, expression of proliferative cell nuclear antigen (PCNA), termin... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803977 Wed, 04 May 2011 23:00:00 +0100 4803977 http://www.medworm.com/index.php?rid=4804001&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21443424%26dopt%3DAbstract Authors: Tucker JD, Luckinbill LS Abstract Chromosome translocations are the hallmark of exposure to ionizing radiation, but they also occur spontaneously, and their frequencies increase dramatically with age. This complicates dosimetry unless a pre-exposure sample is available for each putatively exposed individual. Here we use published values for translocations in unexposed subjects from a wide range of ages, together with data from an in vitro (137)Cs dose-response curve, to estimate the minimum dose of whole-body radiation that is detectable by translocation analyses in individuals of a given age. For subjects aged 20 to 69 years, we show that the minimum detectable acute dose increases linearly with age at a rate of 0.179, 0.218 and 0.256 cGy per year for significance levels of... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4804001 Sat, 30 Apr 2011 23:00:00 +0100 4804001 http://www.medworm.com/index.php?rid=4804000&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21443425%26dopt%3DAbstract In conclusion, oral supplementation with antioxidants appears to be an effective approach for radioprotection against hematopoietic cell death. PMID: 21443425 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4804000 Sat, 30 Apr 2011 23:00:00 +0100 4804000 http://www.medworm.com/index.php?rid=4803983&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21529145%26dopt%3DAbstract Authors: Fu Q, Berbée M, Wang W, Boerma M, Wang J, Schmid HA, Hauer-Jensen M Abstract The somatostatin analog SOM230 has potent radioprophylactic and radiation mitigating properties that are unrelated to cytoprotection but appear to be due to suppression of secretion of pancreatic enzymes into the intestinal lumen. To determine the maximal postirradiation time window for administration, male CD2F1 mice were exposed to 8.5-11 Gy total-body radiation; SOM230 (0.5, 2 or 5 mg/kg) or vehicle was given by twice daily subcutaneous injections for 14 days, beginning 24-72 h after irradiation, and 30-day animal survival was recorded. The contribution of the gut to systemic cytokine levels was estimated by analyzing plasma samples obtained simultaneously from the portal vein and carotid arte... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803983 Thu, 28 Apr 2011 23:00:00 +0100 4803983 http://www.medworm.com/index.php?rid=4803982&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21529146%26dopt%3DAbstract This study examined the terminal maturation of megakaryocytes and platelet production derived from hematopoietic stem cells irradiated with heavy-ion beams. CD34(+) cells derived from human placental/umbilical cord blood were exposed to monoenergetic carbon-ion beams (LET  =  50 keV/µm) and then cultured in a serum-free medium supplemented with thrombopoietin and interleukin-3. There was no significant difference in megakaryocyte-specific markers between nonirradiated control and irradiated cells. Expression of Tie-2, a receptor that acts in early hematopoiesis, showed a significant 1.31-fold increase after 2 Gy irradiation compared to control cells on day 7. There was a significant increase in Tie-2 mRNA expression. In addition, the expression of other mRNAs, such as PECAM1, SELP a... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803982 Thu, 28 Apr 2011 23:00:00 +0100 4803982 http://www.medworm.com/index.php?rid=4803986&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21520996%26dopt%3DAbstract Authors: Moroni M, Coolbaugh TV, Lombardini E, Mitchell JM, Moccia KD, Shelton LJ, Nagy V, Whitnall MH Abstract Additional large animal models for the acute radiation syndrome (ARS) would facilitate countermeasure development. We demonstrate here that Gottingen minipigs develop hematopoietic ARS symptoms similar to those observed in canines, non-human primates (NHPs) and humans. Dosimetry for whole-body γ irradiation (0.6 Gy/min) was performed using electronic paramagnetic resonance (EPR) with alanine; National Institute of Standards and Technology (NIST)-calibrated alanine pellets and water-filled Plexiglas phantoms were used. After irradiations of 1.6-2.0 Gy, blood pancytopenia was observed for several weeks, accompanied by the characteristic ARS stages: prodromal symptoms, latent... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803986 Mon, 25 Apr 2011 23:00:00 +0100 4803986 http://www.medworm.com/index.php?rid=4803985&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21520997%26dopt%3DAbstract Authors: Kennedy AR, Ware JH, Carlton W, Davis JG Abstract We have previously reported data from a long-term carcinogenesis study indicating that dietary antioxidant supplements can suppress radiation-induced malignant lymphoma and harderian gland tumors induced by space radiations (specifically, 1 GeV/n iron ions or protons) in CBA/J mice. Two different antioxidant dietary supplements were used in these studies: a supplement containing a mixture of antioxidant agents [l-selenomethionine (SeM), N-acetyl cysteine (NAC), ascorbic acid, co-enzyme Q10, α-lipoic acid and vitamin E succinate], termed the AOX supplement, and another supplement known as Bowman-Birk Inhibitor Concentrate (BBIC). In the present report, the results from the earlier analysis of the harderian gland data from the ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803985 Mon, 25 Apr 2011 23:00:00 +0100 4803985 http://www.medworm.com/index.php?rid=4803984&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21520998%26dopt%3DAbstract Authors: Meador JA, Ghandhi SA, Amundson SA Abstract Using microarrays to analyze differential gene expression as a function of p53 status and radiation quality, we observed downregulation of a large set of histone genes in p53 wild-type TK6 cells 24 h after exposure to equitoxic doses of high-LET (1.67 Gy 1GeV/n (56)Fe ions) or low-LET (2.5 Gy γ rays) radiation. Quantitative real-time PCR of specific subtypes of core (H2A, H2B, H3 and H4) and linker (H1) histones confirmed this result. DNA synthesis and histone gene expression are tightly coordinated during the S phase of the cell cycle, and both processes are regulated by cell cycle checkpoints in response to DNA damage caused by ionizing radiation. However, we observed similar repression of histone gene expression in both TK6 ce... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803984 Mon, 25 Apr 2011 23:00:00 +0100 4803984 http://www.medworm.com/index.php?rid=4803987&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21486161%26dopt%3DAbstract Authors: Mezentsev A, Amundson SA Abstract Accumulating data suggest that the biological responses to high and low doses of radiation are qualitatively different, necessitating the direct study of low-dose responses to better understand potential risks. Most such studies have used twodimensional culture systems, which may not fully represent responses in three-dimensional tissues. To gain insight into lowdose responses in tissue, we have profiled global gene expression in EPI-200, a three-dimensional tissue model that imitates the structure and function of human epidermis, at 4, 16 and 24 h after exposure to high (2.5 Gy) and low (0.1 Gy) doses of low-LET protons. The most significant gene ontology groups among genes altered in expression were consistent with effects observed at the ti... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803987 Mon, 11 Apr 2011 23:00:00 +0100 4803987 http://www.medworm.com/index.php?rid=4803991&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21476856%26dopt%3DAbstract Authors: Metz-Flamant C, Samson E, Caër-Lorho S, Acker A, Laurier D Abstract Studies of nuclear workers make it possible to directly quantify the risks associated with ionizing radiation exposure at low doses and low dose rates. Studies of the CEA (Commissariat à l'Energie Atomique) and AREVA Nuclear Cycle (AREVA NC) cohort, currently the most informative such group in France, describe the long-term risk to nuclear workers associated with external exposure. Our aim is to assess the risk of mortality from solid cancers among CEA and AREVA NC nuclear workers and its association with external radiation exposure. Standardized mortality ratios (SMRs) were calculated and internal Poisson regressions were conducted, controlling for the main confounding factors [sex, attained age, calendar p... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803991 Thu, 07 Apr 2011 23:00:00 +0100 4803991 http://www.medworm.com/index.php?rid=4803990&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21476857%26dopt%3DAbstract Authors: Satyamitra M, Lombardini E, Graves J, Mullaney C, Ney P, Hunter J, Johnson K, Tamburini P, Wang Y, Springhorn JP, Srinivasan V Abstract Thrombopoietin (TPO) receptor agonists lacking sequence homology to TPO were designed by grafting a known peptide sequence into the hinge and/or kappa constant regions of a human anti-anthrax antibody. Some of these proteins were equipotent to TPO in stimulating cMpl-r activity in vitro and in increasing platelet levels in vivo. ALXN4100TPO (4100TPO), the best agonist in this series with a K(d) of 30 nM for cMpl-r, exhibited potent activity as a radiation countermeasure in CD2F1 mice exposed to lethal total-body radiation from a cobalt-60 γ-ray source. 4100TPO (2 mg/kg, s.c.) administered once either 24 h before or 6 h after TBI showed su... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803990 Thu, 07 Apr 2011 23:00:00 +0100 4803990 http://www.medworm.com/index.php?rid=4803989&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21476858%26dopt%3DAbstract Authors: Waker AJ, Aslam Abstract To improve radiation protection dosimetry for low-energy neutron fields encountered in nuclear power reactor environments, there is increasing interest in modeling neutron energy deposition in metrological instruments such as tissue-equivalent proportional counters (TEPCs). Along with these computational developments, there is also a need for experimental data with which to benchmark and test the results obtained from the modeling methods developed. The experimental work described in this paper is a study of the energy deposition in tissue-equivalent (TE) medium using an in-house built graphite-walled proportional counter (GPC) filled with TE gas. The GPC is a simple model of a standard TEPC because the response of the counter at these energies is alm... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803989 Thu, 07 Apr 2011 23:00:00 +0100 4803989 http://www.medworm.com/index.php?rid=4803988&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21476859%26dopt%3DAbstract Authors: Maks CJ, Wan XS, Ware JH, Romero-Weaver AL, Sanzari JK, Wilson JM, Rightnar S, Wroe AJ, Koss P, Gridley DS, Slater JM, Kennedy AR Abstract In the coming decades human space exploration is expected to move beyond low-Earth orbit. This transition involves increasing mission time and therefore an increased risk of radiation exposure from solar particle event (SPE) radiation. Acute radiation effects after exposure to SPE radiation are of prime importance due to potential mission-threatening consequences. The major objective of this study was to characterize the dose-response relationship for proton and γ radiation delivered at doses up to 2 Gy at high (0.5 Gy/min) and low (0.5 Gy/h) dose rates using white blood cell (WBC) counts as a biological end point. The results demonstra... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803988 Thu, 07 Apr 2011 23:00:00 +0100 4803988 http://www.medworm.com/index.php?rid=4803996&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21466380%26dopt%3DAbstract Authors: Yu T, Parks BW, Yu S, Srivastava R, Gupta K, Wu X, Khaled S, Chang PY, Kabarowski JH, Kucik DF Abstract Radiation exposure from a number of terrestrial sources is associated with an increased risk for atherosclerosis. Recently, concern over whether exposure to cosmic radiation might pose a similar risk for astronauts has increased. To address this question, we examined the effect of 2 to 5 Gy iron ions ((56)Fe), a particularly damaging component of cosmic radiation, targeted to specific arterial sites in male apolipoprotein E-deficient (apoE(-/-)) mice. Radiation accelerated the development of atherosclerosis in irradiated portions of the aorta independent of any systemic effects on plasma lipid profiles or circulating leukocytes. Further, radiation exposure resulted in a mor... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803996 Mon, 04 Apr 2011 23:00:00 +0100 4803996 http://www.medworm.com/index.php?rid=4803995&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21466381%26dopt%3DAbstract Authors: Epperly MW, Wang H, Jones JA, Dixon T, Montesinos CA, Greenberger JS Abstract Many acute and chronic effects of ionizing radiation are mediated by reactive oxygen species and reactive nitrogen species, which deplete antioxidant stores, leading to cellular apoptosis, stem cell depletion and accelerated aging. C57BL/6NHsd mice receiving intravenous MnSOD-PL prior to 9.5 Gy total-body irradiation (TBI) show increased survival from the acute hematopoietic syndrome, and males demonstrated improved long-term survival (Epperly et al., Radiat. Res. 170, 437-444, 2008). We evaluated the effect of an antioxidant-chemopreventive diet compared to a regular diet on long-term survival in female mice. Twenty-four hours before the LD(50/30) dose of 9.5 Gy TBI, subgroups of mice were injecte... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803995 Mon, 04 Apr 2011 23:00:00 +0100 4803995 http://www.medworm.com/index.php?rid=4803994&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21466382%26dopt%3DAbstract Authors: Davis F, Il'yasova D, Rankin K, McCarthy B, Bigner DD Abstract High-dose ionizing radiation is an established risk factor for glioma, but it remains unknown whether moderate- and low-dose radiation increase glioma risk. In this analysis, we assessed the evidence that self-reported exposures to diagnostic ionizing radiation, including computerized tomography (CT) scans, is associated with increased risk of adult glioma. While no independent association was observed for CT scans alone (3+ scans compared to none P  =  0.08 and 1-2 scans compared to none P  =  0.68), our findings suggest an increased risk of adult gliomas with cumulative exposure to three or more CT scans to the head and neck region (OR  =  1.97, 95% CI: 0.92-4.23) limited to those who reported a famil... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803994 Mon, 04 Apr 2011 23:00:00 +0100 4803994 http://www.medworm.com/index.php?rid=4803993&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21466383%26dopt%3DAbstract Authors: Hada M, Zhang Y, Feiveson A, Cucinotta FA, Wu H Abstract To study the effects of low- and high-linear energy transfer (LET) radiation on break locations within a chromosome, we exposed human epithelial cells in vitro to (137)Cs γ rays at both low and high dose rates, secondary neutrons at a low dose rate, and 600 MeV/u iron ions at a high dose rate. Breakpoints were identified using multicolor banding in situ hybridization (mBAND), which paints chromosome 3 in 23 different colored bands. For all four radiation scenarios, breakpoint distributions were found to be different from the predicted distribution based on band width. Detailed analysis of chromosome fragment ends involved in inter- or intrachromosomal exchanges revealed that the distributions of fragment ends participa... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803993 Mon, 04 Apr 2011 23:00:00 +0100 4803993 http://www.medworm.com/index.php?rid=4803992&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21466384%26dopt%3DAbstract Authors: McMahon SJ, Currell FJ Abstract A robust method for fitting to the results of gel electrophoresis assays of damage to plasmid DNA caused by radiation is presented. This method makes use of nonlinear regression to fit analytically derived dose-response curves to observations of the supercoiled, open circular and linear plasmid forms simultaneously, allowing for more accurate results than fitting to individual forms. Comparisons with a commonly used analysis method show that while there is a relatively small benefit between the methods for data sets with small errors, the parameters generated by this method remain much more closely distributed around the true value in the face of increasing measurement uncertainties. This allows for parameters to be specified with greater confid... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803992 Mon, 04 Apr 2011 23:00:00 +0100 4803992 http://www.medworm.com/index.php?rid=4803997&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21456973%26dopt%3DAbstract Authors: Lieberman HB PMID: 21456973 [PubMed - in process] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803997 Thu, 31 Mar 2011 23:00:00 +0100 4803997 http://www.medworm.com/index.php?rid=4803999&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21449714%26dopt%3DAbstract We describe the use of a dedicated CT-guided precision device to irradiate specific sub-regions of the adult mouse brain. Improved CT visualization was accomplished with intrathecal injection of iodinated contrast agent, which enhances the lateral ventricles. T2-weighted MRI images were also used for target localization. Visualization of delivered beams (10 Gy) in tissue was accomplished with immunohistochemical staining for the protein γ-H2AX, a marker of DNA double-strand breaks. γ-H2AX stains showed that the lateral ventricle wall could be targeted with an accuracy of 0.19 mm (n  =  10). In the hippocampus, γ-H2AX staining showed that the dentate gyrus can be irradiated unilaterally with a localized arc treatment. This resulted in a significant decrease of proliferative neural ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803999 Tue, 29 Mar 2011 23:00:00 +0100 4803999 http://www.medworm.com/index.php?rid=4803998&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21449715%26dopt%3DAbstract In conclusion, more accurate dose delivery is achieved when correction factors specific to the animal irradiation setup are applied. Care should be taken when experiments with shields in direct contact with animal skin are involved. PMID: 21449715 [PubMed - as supplied by publisher] (Source: Radiation Research) Radiation Research journals http://www.medworm.com/rss/comments.php?id=4803998 Tue, 29 Mar 2011 23:00:00 +0100 4803998 http://www.medworm.com/index.php?rid=4804003&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21438660%26dopt%3DAbstract Authors: Rezáčová M, Rudolfová G, Tichý A, Bačíková A, Mutná D, Havelek R, Vávrová J, Odrážka K, Lukášová E, Kozubek S Abstract The purpose of this work was to find how fractionated radiation used in the treatment of tumors affects the ability of cancer as well as normal cells to repair induced DNA double-strand breaks (DSBs) and how cells that have lost this ability die. Lymphocytic leukemia cells (MOLT4) were used as an experimental model, and the results were compared to those for normal cell types. The results show that cancer and normal cells were mostly unable to repair all DSBs before the next radiation dose induced new DNA damage. Accumulation of DSBs was observed in normal human fibroblasts and healthy lymphocytes irradiated in vitro after the second radiation ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4804003 Fri, 25 Mar 2011 00:00:00 +0100 4804003 http://www.medworm.com/index.php?rid=4804002&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21438661%26dopt%3DAbstract Authors: Schmid TE, Dollinger G, Hable V, Greubel C, Zlobinskaya O, Michalski D, Auer S, Friedl AA, Schmid E, Molls M, Röper B Abstract Laser accelerated radiotherapy is a potential cancer treatment with proton and carbon-ion beams that is currently under development. Ultra-fast high-energy laser pulses will accelerate ion beams that deliver their dose to a patient in a "pulsed mode" that is expected to differ from conventional irradiation by increasing the dose delivery rate to a tissue voxel by approximately 8 orders of magnitude. In two independently performed experiments at the ion microprobe SNAKE of the 14 MV Munich tandem accelerator, A(L) cells were exposed either to protons with 1-ns pulse durations or to protons applied over 150 ms in continuous irradiation mode. A slightly... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4804002 Fri, 25 Mar 2011 00:00:00 +0100 4804002 http://www.medworm.com/index.php?rid=4638032&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21434782%26dopt%3DAbstract Authors: Satyamitra MM, Kulkarni S, Ghosh SP, Mullaney CP, Condliffe D, Srinivasan V Abstract δ-Tocotrienol (DT3), a vitamin E isoform, is associated with strong antioxidant and immunomodulatory properties. We confirmed the potent antioxidant activity in membrane systems and showed that DT3 is an effective radiation protector and mitigator. DT3 (4 μM, P < 0.001) inhibited lipid peroxidation in mouse liver microsomes and nitric oxide (NO) formation (20 μM DT3, P < 0.01) in RAW264.7 cells, a murine alveolar macrophage line. In CD2F1 mice exposed to lethal total-body radiation from a (60)Co γ-radiation source, a single subcutaneous (s.c.) injection of DT3 before or after irradiation produced a significant increase in 30-day survival. DT3 was effective from 18.75 to 300 mg/kg ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4638032 Thu, 24 Mar 2011 00:00:00 +0100 4638032 http://www.medworm.com/index.php?rid=4578718&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21388294%26dopt%3DAbstract Authors: Hintzsche H, Jastrow C, Kleine-Ostmann T, Stopper H, Schmid E, Schrader T Abstract The aim of this study was to investigate and quantify the production of spindle disturbances in A(L) cells, a human-hamster hybrid cell line, by 0.106 THz radiation (continuous wave). Monolayer cultures in petri dishes were exposed for 5 h to 0.106 THz radiation with power densities ranging from 0.043 mW/cm(2) to 4.3 mW/cm(2) or were kept under sham conditions (negative control) for the same period. As a positive control, 100 µg/ml of the insecticide trichlorfon, which is an aneuploidy-inducing agent, was used for an exposure period of 6 h. During exposure, the sample containers were kept at defined environmental conditions in a modified incubator as required by the cells. Based on a tot... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4578718 Wed, 09 Mar 2011 00:00:00 +0100 4578718 http://www.medworm.com/index.php?rid=4578717&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21388295%26dopt%3DAbstract Authors: Chiu HW, Lin W, Ho SY, Wang YJ Abstract Osteosarcoma is the most common primary malignant bone tumor, occurring mainly in children and adolescents, and survival largely depends on their response to chemotherapy. However, the risk of relapse and adverse outcomes is still high. We investigated the synergistic anti-cancer effects of ionizing radiation combined with arsenic trioxide (ATO) and the mechanisms underlying apoptosis or autophagy induced by combined radiation and ATO treatment in human osteosarcoma cells. We found that exposure to radiation increased the population of HOS cells in the G(2)/M phase within 12 h in a time-dependent manner. Radiation combined with ATO induced a significantly prolonged G(2)/M arrest, consequently enhancing cell death. Furthermore, combined ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4578717 Wed, 09 Mar 2011 00:00:00 +0100 4578717 http://www.medworm.com/index.php?rid=4578735&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21385072%26dopt%3DAbstract This study evaluated changes in DNA methylation in Arabidopsis thaliana plants grown from seeds implanted with low-energy N(+) and Ar(+) ions. Methylation-sensitive amplified polymorphism (MSAP) testing revealed altered DNA methylation patterns after ion implantation at doses of 1 × 10(14) to 1 × 10(16) ions/cm(2). Comparison of the MSAP electrophoretic profiles revealed nine types of polymorphisms in ion-implanted seedlings relative to control seedlings, among which four represented methylation events, three represented demethylation events, and the methylation status of two was uncertain. The diversity of plant DNA methylation was increased by low-energy ion implantation. At the same time, total genomic DNA methylation levels at CCGG sites were unchanged by ion implantation. Moreover, ... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4578735 Tue, 08 Mar 2011 00:00:00 +0100 4578735 http://www.medworm.com/index.php?rid=4578736&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21381866%26dopt%3DAbstract Authors: Boice JD, Cohen SS, Mumma MT, Ellis ED, Eckerman KF, Leggett RW, Boecker BB, Brill AB, Henderson BE Abstract Updated analyses of mortality data are presented on 46,970 workers employed 1948-1999 at Rocketdyne (Atomics International). Overall, 5,801 workers were involved in radiation activities, including 2,232 who were monitored for intakes of radionuclides, and 41,169 workers were engaged in rocket testing or other non-radiation activities. The worker population is unique in that lifetime occupational doses from all places of employment were sought, updated and incorporated into the analyses. Further, radiation doses from intakes of 14 different radionuclides were calculated for 16 organs or tissues using biokinetic models of the International Commission on Radiation Protecti... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4578736 Mon, 07 Mar 2011 00:00:00 +0100 4578736 http://www.medworm.com/index.php?rid=4578738&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21375359%26dopt%3DAbstract Authors: Mitchel RE, Hasu M, Bugden M, Wyatt H, Little MP, Gola A, Hildebrandt G, Priest ND, Whitman SC Abstract The hypothesis that single low-dose exposures (0.025-0.5 Gy) to low-LET radiation given at either high (about 150 mGy/min) or low (1 mGy/min) dose rate would promote aortic atherosclerosis was tested in female C57BL/6J mice genetically predisposed to this disease (ApoE(-/-)). Mice were exposed either at an early stage of disease (2 months of age) and examined 3 or 6 months later or at a late stage of disease (8 months of age) and examined 2 or 4 months later. Changes in aortic lesion frequency, size and severity as well as total serum cholesterol levels and the uptake of lesion lipids by lesion-associated macrophages were assessed. Statistically significant changes in... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4578738 Fri, 04 Mar 2011 00:00:00 +0100 4578738 http://www.medworm.com/index.php?rid=4578737&cid=s_36753_75_f&fid=36753&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21375360%26dopt%3DAbstract Authors: Goetz W, Morgan MN, Baulch JE Abstract It has been acknowledged for many years that radiation exposure induces delayed, non-targeted effects in the progeny of the irradiated cell. Evidence is beginning to demonstrate that among these delayed effects of radiation are epigenetic aberrations, including altered DNA methylation. To test the hypothesis that differences in radiation quality affect radiation-induced DNA methylation profiles, normal AG01522 and RKO colon carcinoma cells were exposed to low-LET X rays and protons or high-LET iron ions. DNA methylation was then evaluated at delayed times using assays for p16 and MGMT promoter, LINE-1 and alu repeat element, and global methylation. The results of these experiments demonstrated radiation-induced changes in repeat element a... Radiation Research journals http://www.medworm.com/rss/comments.php?id=4578737 Fri, 04 Mar 2011 00:00:00 +0100 4578737