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Sample records for radiation inactivates sv40

  1. Ultraviolet radiation inactivates SV40 by disrupting at least four genetic functions

    International Nuclear Information System (INIS)

    Brown, T.C.; Cerutti, P.A.

    1986-01-01

    The most UV sensitive region within the SV40 viral genome contains the transcriptional promotors and enhancers for the early and late viral genes plus part of the origin of DNA replication. Lesions within this regulatory region are 3.2-fold more effective in inactivating viral DNA than is the same amount of damage randomly distributed throughout the viral genome. The region least sensitive to damage lies within the coding portion of the viral coat protein genes, which are expressed only late in infection and would therefore be transcribed from undamaged progeny viral genomes, provided DNA replication occurs. Damage within this region is only 45% as effective in inactivating viral DNA as are randomly distributed lesions. Thus there is a 7-fold difference in the lethal effect of DNA damage within the most and least sensitive regions of the viral genome. Intermediate sensitivities are observed within the transcribed portion of the viral A gene, coding for the T antigen whose expression is required early in infection, and in a region at the terminus of DNA replication. The sum of the individual sensitivities for all regions of the SV40 genome is equal to the total sensitivity of viral DNA subjected to random damage. (author)

  2. Biological activity of SV40 DNA

    International Nuclear Information System (INIS)

    Abrahams, P.J.

    1978-01-01

    This thesis deals with a study on the biological activity of SV40 DNA. The transforming activity of SV40 DNA and DNA fragments is investigated in order to define as precisely as possible the area of the viral genome that is involved in the transformation. The infectivity of SV40 DNA is used to study the defective repair mechanisms of radiation damages of human xeroderma pigmentosum cells. (C.F.)

  3. High throughput testing of the SV40 Large T antigen binding to cellular p53 identifies putative drugs for the treatment of SV40-related cancers

    International Nuclear Information System (INIS)

    Carbone, Michele; Rudzinski, Jennifer; Bocchetta, Maurizio

    2003-01-01

    SV40 has been linked to some human malignancies, and the evidence that this virus plays a causative role in mesothelioma and brain tumors is mounting. The major SV40 oncoprotein is the Large tumor antigen (Tag). A key Tag transforming activity is connected to its capability to bind and inactivate cellular p53. In this study we developed an effective, high throughput, ELISA-based method to study Tag-p53 interaction in vitro. This assay allowed us to screen a chemical library and to identify a chemical inhibitor of the Tag binding to p53. We propose that our in vitro assay is a useful method to identify molecules that may be used as therapeutic agents for the treatment of SV40-related human cancers

  4. Random integration of SV40 in SV40-transformed, immortalized human fibroblasts.

    Science.gov (United States)

    Hara, H; Kaji, H

    1987-02-01

    We have studied the relationship between immortalization of SV40-transformed human embryonic fibroblasts and their SV40 integration sites. From several independently transformed cell pools, we have isolated clones which do not harbor unintegrated SV40 DNA. We have analysed whole-cell DNA from these clones, using the Southern blot method. Our results suggest that no specific integration sites in the cellular genome exist which are a prerequisite for the immortalization process. Although some integration sites were found to be predominant in pre-crisis clones, they could not be detected in the post-crisis clones. This suggests that none of these predominating sites is selected for during the crisis period.

  5. Impaired CK1 delta activity attenuates SV40-induced cellular transformation in vitro and mouse mammary carcinogenesis in vivo.

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    Heidrun Hirner

    repair. Our data show that inactivating mutations in CK1δ impair SV40-induced cellular transformation in vitro and mouse mammary carcinogenesis in vivo.

  6. Internal 40K radiation dose to Indians

    International Nuclear Information System (INIS)

    Ranganathan, S.; Someswara Rao, M.; Nagaratnam, A.; Mishra, U.C.

    2002-01-01

    A group of 350 Indians from both sexes (7-65 years) representing different regions of India was studied for internal 40 K radiation dose from the naturally occurring body 40 K, which was measured in the National Institute of Nutrition (NIN) whole-body counter. Although the 40 K radioactivity reached a peak value by 18 years in female (2,412 Bq) and by 20 years in male (3,058 Bq) and then varied inversely with age in both sexes, the radiation dose did not show such a trend. Boys and girls of 11 years had annual effective dose of nearly 185 mSv, which decreased during adolescence (165 mSv), increased to 175 mSv by 18-20 years in adults and decreased progressively on further ageing to 99 mSv in males and 69 mSv in females at 65 years. The observed annual effective dose (175 mSv) of the young adults was close to that of the ICRP Reference Man (176 mSv) and Indian Reference Man (175 mSv). With a mean specific activity of 55 Bq/kg for the subjects and a conversion coefficient close to 3 mSv per annum per Bq/kg, the average annual effective dose from the internal 40 K turned out to be 165 mSv for Indians. (author)

  7. Properties of the simian virus 40 (SV40) large T antigens encoded by SV40 mutants with deletions in gene A.

    Science.gov (United States)

    Cole, C N; Tornow, J; Clark, R; Tjian, R

    1986-01-01

    The biochemical properties of the large T antigens encoded by simian virus 40 (SV40) mutants with deletions at DdeI sites in the SV40 A gene were determined. Mutant large T antigens containing only the first 138 to 140 amino acids were unable to bind to the SV40 origin of DNA replication as were large T antigens containing at their COOH termini 96 or 97 amino acids encoded by the long open reading frame located between 0.22 and 0.165 map units (m.u.). All other mutant large T antigens were able to bind to the SV40 origin of replication. Mutants with in-phase deletions at 0.288 and 0.243 m.u. lacked ATPase activity, but ATPase activity was normal in mutants lacking origin-binding activity. The 627-amino acid large T antigen encoded by dlA2465, with a deletion at 0.219 m.u., was the smallest large T antigen displaying ATPase activity. Mutant large T antigens with the alternate 96- or 97-amino acid COOH terminus also lacked ATPase activity. All mutant large T antigens were found in the nuclei of infected cells; a small amount of large T with the alternate COOH terminus was also located in the cytoplasm. Mutant dlA2465 belonged to the same class of mutants as dlA2459. It was unable to form plaques on CV-1p cells at 37 or 32 degrees C but could form plaques on BSC-1 monolayers at 37 degrees C but not at 32 degrees C. It was positive for viral DNA replication and showed intracistronic complementation with any group A mutant whose large T antigen contained a normal carboxyl terminus. These findings and those of others suggest that both DNA binding and ATPase activity are required for the viral DNA replication function of large T antigen, that these two activities must be located on the same T antigen monomer, and that these two activities are performed by distinct domains of the polypeptide. These domains are distinct and separable from the domain affected by the mutation of dlA2465 and indicate that SV40 large T antigen is made up of at least three separate functional

  8. Test of models for replication of SV40 DNA following UV irradiation

    International Nuclear Information System (INIS)

    Barnett, S.W.

    1983-01-01

    The replication of SV40 DNA immediately after irradiation of infected monkey cells has been examined. SV40 DNA synthesis is inhibited in a UV fluence-dependent fashion, and the synthesis of completely replicated (Form I) SV40 molecules is more severely inhibited than is total SV40 DNA synthesis. Two models for DNA replication-inhibition have been tested. Experimental results have been compared to those predicted by mathematical models derived to describe two possible molecular mechanisms of replication inhibition. No effect of UV irradiation on the uptake and phosphorylation of 3 H-thymidine nor on the size of the intracellular deoxythymidine triphosphate pool of SV40-infected cells have been observed, validating the use of 3 H-thymidine incorporation as a measure of DNA synthesis in this system. In vitro studies have been performed to further investigate the mechanism of dimer-specific inhibition of completion of SV40 DNA synthesis observed in in vivo. The results of these studies are consistent with a mechanism of discontinuous synthesis past dimer sites, but it is equally possible that the mechanism of DNA replication of UV-damaged DNA in the in vitro system is different from that which occurs in vivo

  9. The monetary value of the man-mSv for Korean NPP radiation workers assessed by the radiation aversion factor

    International Nuclear Information System (INIS)

    Lee, B. I.; Suh, D. H.; Kim, S. I.; Jeong, M. S.; Lim, Y. K.

    2008-01-01

    The monetary value of the man-mSv for operators of Korean nuclear power plants (NPPs) was calculated using a radiation aversion factor based on a survey of NPP workers. Initially, the life expectancy in the population is 79.4 y, the average age of cancer occurrence is 60 y, the average annual wage for an electric worker is 56 000 $ y -1 and the nominal risk coefficient induced by radiation is 4.2 E-5 mSv were used to evaluate the basic monetary value (α base) resulting in 45.6 $ mSv -1 . To investigate the degree of radiation aversion, the subject of the investigation was selected as the working radiation workers in 10 NPPs in Korea (Kori 1-2, Yeonggwang 1-3, Ulchin 1-3 and Wolseong 1-2). In August 2010, with the cooperation of KHNP and partner companies, a total of 2500 survey questionnaires to 10 NPPs (or 250 surveys to each NPP) were distributed to currently employed radiation workers. From these, 2157 responses were obtained between August and October 2010. The assessed radiation aversion factor and the monetary value of the man-mSv from the calculated radiation aversion factor were 1.26 and ∼50 $ in the 0-1 mSv range, 1.38 and ∼200 $ in the 1-5 mSv range, 1.52 and ∼1000 $ in the 5-10 mSv range, 1.65 and ∼4000 $ in the 10-20 mSv range and 1.74 and ∼8500 $ >20 mSv. (authors)

  10. Comparative human cellular radiosensitivity: I. The effect of SV40 transformation and immortalisation on the gamma-irradiation survival of skin derived fibroblasts from normal individuals and from ataxia-telangiectasia patients and heterozygotes.

    Science.gov (United States)

    Arlett, C F; Green, M H; Priestley, A; Harcourt, S A; Mayne, L V

    1988-12-01

    We have compared cell killing following 60Co gamma irradiation in 22 primary human fibroblast strains, nine SV40-immortalized human fibroblast lines and seven SV40-transformed pre-crisis human fibroblast cultures. We have examined material from normal individuals, from ataxia-telangiectasia (A-T) patients and from A-T heterozygotes. We have confirmed the greater sensitivity of A-T derived cells to gamma radiation. The distinction between A-T and normal cells is maintained in cells immortalized by SV40 virus but the immortal cells are more gamma radiation resistant than the corresponding primary fibroblasts. Cells transformed by plasmids (pSV3gpt and pSV3neo) expressing SV40 T-antigen, both pre- and post-crisis, show this increased resistance, indicating that it is expression of SV40 T-antigen, rather than immortalization per se which is responsible for the change. We use D0, obtained from a straight line fit, and D, estimated from a multitarget curve, as parameters to compare radiosensitivity. We suggest that both have their advantages; D0 is perhaps more reproducible, but D is more realistic when comparing shouldered and non-shouldered data.

  11. The Influence of SV40 polyA on Gene Expression of Baculovirus Expression Vector Systems.

    Directory of Open Access Journals (Sweden)

    Tamer Z Salem

    Full Text Available The simian virus 40 polyadenylation signal (SV40 polyA has been routinely inserted downstream of the polyhedrin promoter in many baculovirus expression vector systems (BEVS. In the baculovirus prototype Autographa californica multiple nucleopolyhedrovirus (AcMNPV, the polyhedrin promoter (very late promoter transcribes its gene by a viral RNA polymerase therefore there is no supporting evidence that SV40 polyA is required for the proper gene expression under the polyhedrin promoter. Moreover, the effect of the SV40 polyA sequence on the polyhedrin promoter activity has not been tested either at its natural polyhedrin locus or in other loci in the viral genome. In order to test the significance of adding the SV40 polyA sequence on gene expression, the expression of the enhanced green fluorescent protein (egfp was evaluated with and without the presence of SV40 polyA under the control of the polyhedrin promoter at different genomic loci (polyherin, ecdysteroid UDP-glucosyltransferase (egt, and gp37. In this study, spectrofluorometry and western blot showed reduction of EGFP protein for all recombinant viruses with SV40 polyA, whereas qPCR showed an increase in the egfp mRNA levels. Therefore, we conclude that SV40 polyA increases mRNA levels but decreases protein production in the BEVS when the polyhedrin promoter is used at different loci. This work suggests that SV40 polyA in BEVSs should be replaced by an AcMNPV late gene polyA for optimal protein production or left untouched for optimal RNA production (RNA interference applications.

  12. The Influence of SV40 polyA on Gene Expression of Baculovirus Expression Vector Systems

    Science.gov (United States)

    Salem, Tamer Z.; Seaborn, Craig P.; Turney, Colin M.; Xue, Jianli; Shang, Hui; Cheng, Xiao-Wen

    2015-01-01

    The simian virus 40 polyadenylation signal (SV40 polyA) has been routinely inserted downstream of the polyhedrin promoter in many baculovirus expression vector systems (BEVS). In the baculovirus prototype Autographa californica multiple nucleopolyhedrovirus (AcMNPV), the polyhedrin promoter (very late promoter) transcribes its gene by a viral RNA polymerase therefore there is no supporting evidence that SV40 polyA is required for the proper gene expression under the polyhedrin promoter. Moreover, the effect of the SV40 polyA sequence on the polyhedrin promoter activity has not been tested either at its natural polyhedrin locus or in other loci in the viral genome. In order to test the significance of adding the SV40 polyA sequence on gene expression, the expression of the enhanced green fluorescent protein (egfp) was evaluated with and without the presence of SV40 polyA under the control of the polyhedrin promoter at different genomic loci (polyherin, ecdysteroid UDP-glucosyltransferase (egt), and gp37). In this study, spectrofluorometry and western blot showed reduction of EGFP protein for all recombinant viruses with SV40 polyA, whereas qPCR showed an increase in the egfp mRNA levels. Therefore, we conclude that SV40 polyA increases mRNA levels but decreases protein production in the BEVS when the polyhedrin promoter is used at different loci. This work suggests that SV40 polyA in BEVSs should be replaced by an AcMNPV late gene polyA for optimal protein production or left untouched for optimal RNA production (RNA interference applications). PMID:26659470

  13. Radiation Doses to Hanford Workers from Natural Potassium-40

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lynch, Timothy P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weier, Dennis R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2009-02-01

    The chemical element potassium is an essential mineral in people and is subject to homeostatic regulation. Natural potassium comprises three isotopes, 39K, 40K, and 41K. Potassium-40 is radioactive, with a half life of 1.248 billion years. In most transitions, it emits a β particle with a maximum energy of 0.560 MeV, and sometimes a gamma photon of 1.461 MeV. Because it is ubiquitous, 40K produces radiation dose to all human beings. This report contains the results of new measurements of 40K in 248 adult females and 2,037 adult males performed at the Department of Energy Hanford Site in 2006 and 2007. Potassium concentrations diminish with age, are generally lower in women than in men, and decrease with body mass index (BMI). The average annual effective dose from 40K in the body is 0.149 mSv y-1 for men and 0.123 mSv y-1 women respectively. Averaged over both men and women, the average effective dose per year is 0.136 mSv y-1. Calculated effective doses range from 0.069 to 0.243 mSv y-1 for adult males, and 0.067 to 0.203 mSv y-1 for adult females, a roughly three-fold variation for each gender. The need for dosimetric phantoms with a greater variety of BMI values should be investigated. From our data, it cannot be determined whether the potassium concentration in muscle in people with large BMI values differs from that in people with small BMI values. Similarly, it would be important to know the potassium concentration in other soft tissues, since much of the radiation dose is due to beta radiation, in which the source and target tissues are the same. These uncertainties should be evaluated to determine their consequences for dosimetry.

  14. SV40-transformed human fibroblasts: evidence for cellular aging in pre-crisis cells.

    Science.gov (United States)

    Stein, G H

    1985-10-01

    Pre-crisis SV40-transformed human diploid fibroblast (HDF) cultures have a finite proliferative lifespan, but they do not enter a viable senescent state at end of lifespan. Little is known about either the mechanism for this finite lifespan in SV40-transformed HDF or its relationship to finite lifespan in normal HDF. Recently we proposed that in normal HDF the phenomena of finite lifespan and arrest in a viable senescent state depend on two separate processes: 1) an age-related decrease in the ability of the cells to recognize or respond to serum and/or other mitogens such that the cells become functionally mitogen-deprived at the end of lifespan; and 2) the ability of the cells to enter a viable, G1-arrested state whenever they experience mitogen deprivation. In this paper, data are presented that suggest that pre-crisis SV40-transformed HDF retain the first process described above, but lack the second process. It is shown that SV40-transformed HDF have a progressively decreasing ability to respond to serum as they age, but they continue to traverse the cell cycle at the end of lifespan. Concomitantly, the rate of cell death increases steadily toward the end of lifespan, thereby causing the total population to cease growing and ultimately to decline. Previous studies have shown that when SV40-transformed HDF are environmentally serum deprived, they likewise exhibit continued cell cycle traverse coupled with increased cell death. Thus, these results support the hypothesis that pre-crisis SV40-transformed HDF still undergo the same aging process as do normal HDF, but they end their lifespan in crisis rather than in the normal G1-arrested senescent state because they have lost their ability to enter a viable, G1-arrested state in response to mitogen deprivation.

  15. Characterization of SV-40 Tag rats as a model to study prostate cancer

    International Nuclear Information System (INIS)

    Harper, Curt E; Patel, Brijesh B; Cook, Leah M; Wang, Jun; Shirai, Tomoyuki; Eltoum, Isam A; Lamartiniere, Coral A

    2009-01-01

    Prostate cancer is the second most frequently diagnosed cancer in men. Animal models that closely mimic clinical disease in humans are invaluable tools in the fight against prostate cancer. Recently, a Simian Virus-40 T-antigen (SV-40 Tag) targeted probasin promoter rat model was developed. This model, however, has not been extensively characterized; hence we have investigated the ontogeny of prostate cancer and determined the role of sex steroid receptor and insulin-like growth factor-1 (IGF-1) signaling proteins in the novel SV-40 Tag rat. The SV-40 Tag rat was histopathologically characterized for time to tumor development, incidence and multiplicity and in the ventral, dorsal, lateral and anterior lobes of the prostate. Immunoassay techniques were employed to measure cell proliferation, apoptosis, and sex steroid receptor and growth factor signaling-related proteins. Steroid hormone concentrations were measured via coated well enzyme linked immunosorbent assay (ELISA) kits. Prostatic intraepithelial neoplasia (PIN) and well-differentiated prostate cancer developed as early as 2 and 10 weeks of age, respectively in the ventral prostate (VP) followed by in the dorsolateral (DLP). At 8 weeks of age, testosterone and dihydrotestosterone (DHT) concentrations in SV-40 Tag rats were increased when compared to non-transgenic rats. High cell proliferation and apoptotic indices were found in VP and DLP of transgenic rats. Furthermore, we observed increased protein expression of androgen receptor, IGF-1, IGF-1 receptor, and extracellular signal-regulated kinases in the prostates of SV-40 Tag rats. The rapid development of PIN and prostate cancer in conjunction with the large prostate size makes the SV-40 Tag rat a useful model for studying prostate cancer. This study provides evidence of the role of sex steroid and growth factor proteins in prostate cancer development and defines appropriate windows of opportunity for preclinical trials and aids in the rational design of

  16. Analysis of plasma membrane Ca(2+)-ATPase expression in control and SV40-transformed human fibroblasts.

    Science.gov (United States)

    Reisner, P D; Brandt, P C; Vanaman, T C

    1997-01-01

    It has been long known that neoplastic transformation is accompanied by a lowered requirement for extracellular Ca2+ for growth. The studies presented here demonstrate that human fibroblastic cell lines produce the two commonly found 'housekeeping' isoforms of the plasma membrane Ca(2+)-ATPase (PMCA), PMCA1b and 4b, and at the expression of both is demonstrably lower in cell lines neoplastically transformed by SV40 than in the corresponding parental cell lines. Western blot analyses of lysates from control (GM00037) and SV40-transformed (GM00637) skin fibroblasts revealed a 138 kDa PMCA whose level was significantly lower in the SV40-transformed cells relative to either total cellular protein or alpha-tubulin. Similar analyses of plasma membrane preparations from control WI-38) and SV40-transformed (WI-38VA13) lung fibroblasts revealed 3-4-fold lower levels of PMCA in the SV40-transformed cells. Competitive ELISAs performed on detergent solubilized plasma membrane preparations indicated at least 3-4-fold lower levels of PMCA in the SV40-transformed cell lines compared to controls. Reverse transcriptase coupled-PCR analyses showed that PMCA1b and PMCA4b were the only isoforms expressed in all four cell lines. The PMCA4b mRNA level detected by Northern analysis also was substantially lower in SV40 transformed skin fibroblasts than in non-transformed fibroblasts. Quantitative RT-PCR analyses showed levels of PMCA1b and 4b mRNAs to be 5 and 10-fold lower, respectively, in GM00637 than in GM00037 when the levels of PCR products were normalized to glyceraldehyde-3-phosphate dehydrogenase (G3PDH) mRNA. These results demonstrate that the expression of these distinct PMCA genes is substantially lower in SV40 transformed human skin and lung fibroblasts and may be coordinately regulated in these cells.

  17. Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants

    International Nuclear Information System (INIS)

    Kawano, Masaaki; Morikawa, Katsuma; Suda, Tatsuya; Ohno, Naohito; Matsushita, Sho; Akatsuka, Toshitaka; Handa, Hiroshi; Matsui, Masanori

    2014-01-01

    Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A ⁎ 02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A ⁎ 02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. - Highlights: • We constructed chimeric SV40-VLPs carrying an influenza virus-derived CTL epitope. • Chimeric SV40-VLPs induce influenza-specific CTLs in mice without adjuvants. • Chimeric SV40-VLPs induce heterosubtypic protection against influenza A viruses. • Chimeric SV40-VLPs induce long-lasting memory CTLs. • Chimeric SV40-VLPs is a promising vaccine platform with self-adjuvant properties

  18. Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Masaaki [Department of Allergy and Immunology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Morikawa, Katsuma [Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501 (Japan); Suda, Tatsuya [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Laboratory for Immunopharmacology of Microbial Products, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Ohno, Naohito [Laboratory for Immunopharmacology of Microbial Products, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Matsushita, Sho [Department of Allergy and Immunology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Allergy Center, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Akatsuka, Toshitaka [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Handa, Hiroshi, E-mail: handa.h.aa@m.titech.ac.jp [Solutions Research Laboratory, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8503 (Japan); Matsui, Masanori, E-mail: mmatsui@saitama-med.ac.jp [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan)

    2014-01-05

    Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A{sup ⁎}02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A{sup ⁎}02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. - Highlights: • We constructed chimeric SV40-VLPs carrying an influenza virus-derived CTL epitope. • Chimeric SV40-VLPs induce influenza-specific CTLs in mice without adjuvants. • Chimeric SV40-VLPs induce heterosubtypic protection against influenza A viruses. • Chimeric SV40-VLPs induce long-lasting memory CTLs. • Chimeric SV40-VLPs is a promising vaccine platform with self-adjuvant properties.

  19. A mouse model for chronic lymphocytic leukemia based on expression of the SV40 large T antigen

    DEFF Research Database (Denmark)

    ter Brugge, Petra J; Ta, Van B T; de Bruijn, Marjolein J W

    2009-01-01

    The simian virus 40 (SV40) T antigen is a potent oncogene able to transform many cell types and has been implicated in leukemia and lymphoma. In this report, we have achieved sporadic SV40 T-antigen expression in mature B cells in mice, by insertion of a SV40 T antigen gene in opposite...... transcriptional orientation in the immunoglobulin (Ig) heavy (H) chain locus between the D and J(H) segments. SV40 T-antigen expression appeared to result from retention of the targeted germline allele and concomitant antisense transcription of SV40 large T in mature B cells, leading to chronic lymphocytic...... leukemia (CLL). Although B-cell development was unperturbed in young mice, aging mice showed accumulation of a monoclonal B-cell population in which the targeted IgH allele was in germline configuration and the wild-type IgH allele had a productive V(D)J recombination. These leukemic B cells were Ig...

  20. SV40 Assembly In Vivo and In Vitro

    Directory of Open Access Journals (Sweden)

    Ariella Oppenheim

    2008-01-01

    Full Text Available The Simian virus 40 (SV40 capsid is a T = 7d icosahedral lattice ∼45 nm in diameter surrounding the ∼5 kb circular minichromosome. The outer shell is composed of 360 monomers of the major capsid protein VP1, tightly bound in 72 pentamers. VP1 is a jellyroll β-barrel, with extending N- and C-terminal arms. The N-terminal arms bind DNA and face the interior of the capsid. The flexible C-arms tie together the 72 pentamers in three distinct kinds of interactions, thus facilitating the formation of a T = 7 icosahedron from identical pentameric building blocks. Assembly in vivo was shown to occur by addition of capsomers around the DNA. We apply a combination of biochemical and genetic approaches to study SV40 assembly. Our in vivo and in vitro studies suggest the following model: one or two capsomers bind at a high affinity to ses, the viral DNA encapsidation signal, forming the nucleation centre for assembly. Next, multiple capsomers attach concomitantly, at lower affinity, around the minichromosome. This increases their local concentration facilitating rapid, cooperative assembly reaction. Formation of the icosahedron proceeds either by gradual addition of single pentamers to the growing shell or by concerted assembly of pentamer clusters.

  1. A monoclonal antibody against SV40 large T antigen (PAb416) does not label Merkel cell carcinoma.

    Science.gov (United States)

    Pelletier, Daniel J; Czeczok, Thomas W; Bellizzi, Andrew M

    2018-07-01

    Merkel cell carcinoma represents poorly differentiated neuroendocrine carcinoma of cutaneous origin. In most studies, the vast majority of Merkel cell carcinomas are Merkel cell polyomavirus (MCPyV)-associated. SV40 polyomavirus immunohistochemistry is typically used in the diagnosis of other polyomavirus-associated diseases, including tubulointerstitial nephritis and progressive multifocal leukoencephalopathy, given cross-reactivity with BK and JC polyomaviruses. MCPyV-specific immunohistochemistry is commercially available, but, if antibodies against SV40 also cross-reacted with MCPyV, that would be advantageous from a resource-utilisation perspective. Tissue microarrays were constructed from 39 Merkel cell carcinomas, 24 small-cell lung carcinomas, and 18 extrapulmonary visceral small-cell carcinomas. SV40 large T antigen immunohistochemistry (clone PAb416) was performed; MCPyV large T antigen immunohistochemistry (clone CM2B4) had been previously performed. UniProt was used to compare the amino acid sequences of the SV40, BK, JC and MCPyV large T antigens, focusing on areas recognised by the PAb416 and CM2B4 clones. SV40 immunohistochemistry was negative in all tumours; MCPyV immunohistochemistry was positive in 38% of Merkel cell carcinomas and in 0% of non-cutaneous poorly differentiated neuroendocrine carcinomas. UniProt analysis revealed a high degree of similarity between SV40, BK, and JC viruses in the region recognised by PAb416. There was less homology between SV40 and MCPyV in this region, which was also interrupted by two long stretches of amino acids unique to MCPyV. The CM2B4 clone recognises a unique epitope in one of these stretches. The PAb416 antibody against the SV40 large T antigen does not cross-react with MCPyV large T antigen, and thus does not label Merkel cell carcinoma. © 2018 John Wiley & Sons Ltd.

  2. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated ras oncogene and SV40 T-antigen.

    Science.gov (United States)

    Su, L N; Little, J B

    1992-08-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. Cells transfected with EJ ras alone showed no morphological alterations nor significant changes in radiosensitivity. Cell clones expressing ras and/or SV40 T-antigen showed a reduced requirement for serum supplements, an increase in aneuploidy and chromosomal aberrations, and enhanced growth in soft agar as an early cellular response to SV40 T-antigen expression. The sequential order of transfection with SV40 T-antigen and ras influenced radio-sensitivity but not the induction of morphological changes. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself.

  3. Generation of a Vero-Based Packaging Cell Line to Produce SV40 Gene Delivery Vectors for Use in Clinical Gene Therapy Studies

    Directory of Open Access Journals (Sweden)

    Miguel G. Toscano

    2017-09-01

    Full Text Available Replication-defective (RD recombinant simian virus 40 (SV40-based gene delivery vectors hold a great potential for clinical applications because of their presumed non-immunogenicity and capacity to induce immune tolerance to the transgene products in humans. However, the clinical use of SV40 vectors has been hampered by the lack of a packaging cell line that produces replication-competent (RC free SV40 particles in the vector production process. To solve this problem, we have adapted the current SV40 vector genome used for the production of vector particles and generated a novel Vero-based packaging cell line named SuperVero that exclusively expresses the SV40 large T antigen. SuperVero cells produce similar numbers of SV40 vector particles compared to the currently used packaging cell lines, albeit in the absence of contaminating RC SV40 particles. Our unique SV40 vector platform named SVac paves the way to clinically test a whole new generation of SV40-based therapeutics for a broad range of important diseases.

  4. Host-cell reactivation of ultraviolet-irradiated SV 40 DNA in five complementation groups of xeroderma pigmentosum

    International Nuclear Information System (INIS)

    Abrahams, P.J.; Eb, A.J. van der

    1976-01-01

    Host-cell reactivation of UV-irradiated double-stranded SV40 DNA was studied in BSC-1 monkey cells, normal human cells, heterozygous Xeroderma pigmentosum xp cells, representative cell strains of the five complemention groups of XP and in XP 'variant' cells. The following percentages of survival of the plaque-forming ability of double-stranded SV40 DNA were found in XP cells compared with the value found in normal monkey and human cells: groupA, 13%; group B, 30%; group C, 18%; group D, 14%; group E, 59%; and in the heterozygous XP cells almost 100%. The survival in XP 'variant' cells was 66%. The survival of single-stranded SV40 DNA in BSC-1 cells was much lower than that of double-stranded SV40 DNA in XP cells of complementation group A, which possibly indicates that some repair of UV damage occurs even in XP cells of group A

  5. Early superoxide dismutase alterations during SV40-transformation of human fibroblasts.

    Science.gov (United States)

    Bravard, A; Hoffschir, F; Sabatier, L; Ricoul, M; Pinton, A; Cassingena, R; Estrade, S; Luccioni, C; Dutrillaux, B

    1992-11-11

    The expression of superoxide dismutases (SOD) 1 and 2 was studied in 4 clones of human fibroblasts after their infection by simian virus 40 (SV40), in parallel with the alterations of chromosomes 21 and chromosome 6q arms, carrying the genes that encode for SOD1 and SOD2 respectively. For all clones, a similar scheme with 2 main phases was observed for both chromosome and SOD variations. The first phase, defined as the pre-crisis phase, was characterized by chromosomal instability, but maintenance of normal numbers of chromosome 6q arms and chromosomes 21. The level of SOD2 mRNA was high, while SOD2 activity and immunoreactive protein were low. SOD1 protein and activity were decreased. In the second phase, defined as the post-crisis phase, the accumulation of clonal chromosomal rearrangements led to the loss of 6q arms, while the number of chromosomes 21 remained normal. SOD2 mRNA level was decreased and SOD2 immunoreactive protein and activity remained low. SOD1 protein and activity increased with passages, reaching values similar to those of control cells at late passages. As in established SV40-transformed human fibroblast cell lines, good correlation was found between SOD2 activity and the relative number of 6q arms. These results allow us to reconstruct the sequence of events leading to the decrease of SOD2, a possible tumor-suppressor gene, during the process of SV40-transformation of human fibroblasts.

  6. SV40 host-substituted variants: a new look at the monkey DNA inserts and recombinant junctions.

    Science.gov (United States)

    Singer, Maxine; Winocour, Ernest

    2011-04-10

    The available monkey genomic data banks were examined in order to determine the chromosomal locations of the host DNA inserts in 8 host-substituted SV40 variant DNAs. Five of the 8 variants contained more than one linked monkey DNA insert per tandem repeat unit and in all cases but one, the 19 monkey DNA inserts in the 8 variants mapped to different locations in the monkey genome. The 50 parental DNAs (32 monkey and 18 SV40 DNA segments) which spanned the crossover and flanking regions that participated in monkey/monkey and monkey/SV40 recombinations were characterized by substantial levels of microhomology of up to 8 nucleotides in length; the parental DNAs also exhibited direct and inverted repeats at or adjacent to the crossover sequences. We discuss how the host-substituted SV40 variants arose and the nature of the recombination mechanisms involved. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants.

    Science.gov (United States)

    Kawano, Masaaki; Morikawa, Katsuma; Suda, Tatsuya; Ohno, Naohito; Matsushita, Sho; Akatsuka, Toshitaka; Handa, Hiroshi; Matsui, Masanori

    2014-01-05

    Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A*02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A*02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. © 2013 Elsevier Inc. All rights reserved.

  8. Transformation of SV40-immortalized human uroepithelial cells by 3-methylcholanthrene increases IFN- and Large T Antigen-induced transcripts

    Directory of Open Access Journals (Sweden)

    Easton Marilyn J

    2010-02-01

    Full Text Available Abstract Background Simian Virus 40 (SV40 immortalization followed by treatment of cells with 3-methylcholanthrene (3-MC has been used to elicit tumors in athymic mice. 3-MC carcinogenesis has been thoroughly studied, however gene-level interactions between 3-MC and SV40 that could have produced the observed tumors have not been explored. The commercially-available human uroepithelial cell lines were either SV40-immortalized (HUC or SV40-immortalized and then 3-MC-transformed (HUC-TC. Results To characterize the SV40 - 3MC interaction, we compared human gene expression in these cell lines using a human cancer array and confirmed selected changes by RT-PCR. Many viral Large T Antigen (Tag expression-related changes occurred in HUC-TC, and it is concluded that SV40 and 3-MC may act synergistically to transform cells. Changes noted in IFP 9-27, 2'-5' OAS, IF 56, MxA and MxAB were typical of those that occur in response to viral exposure and are part of the innate immune response. Because interferon is crucial to innate immune host defenses and many gene changes were interferon-related, we explored cellular growth responses to exogenous IFN-γ and found that treatment impeded growth in tumor, but not immortalized HUC on days 4 - 7. Cellular metabolism however, was inhibited in both cell types. We conclude that IFN-γ metabolic responses were functional in both cell lines, but IFN-γ anti-proliferative responses functioned only in tumor cells. Conclusions Synergism of SV40 with 3-MC or other environmental carcinogens may be of concern as SV40 is now endemic in 2-5.9% of the U.S. population. In addition, SV40-immortalization is a generally-accepted method used in many research materials, but the possibility of off-target effects in studies carried out using these cells has not been considered. We hope that our work will stimulate further study of this important phenomenon.

  9. Some factors affecting urokinase inactivation. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Iwata, Hiroo; Iketa, Yoshito

    1985-10-01

    The enzymatic activity of urokinase adsorbed on various polymer surfaces was measured to study the interaction between protein and polymers. The polymer films on which urokinase was adsorbed were exposed to either a high temperature or ..gamma..-radiation. The thermal inactivation rates were higher on hydrophobic polymers such as poly(ethylene terephthalate), nylon 6, and poly(vinylidene fluoride) than hydrophilic polymers like cellulose and ethylene-vinyl alcohol copolymer, indicating their substantial dependence on the interfacial free energy between the polymer and water. A similar dependence was also seen for the ..gamma..-radiation inactivation. Urokinase adsorbed on the hydrophobic polymers lost more easily its enzymatic activity by exposure to ..gamma..-radiation. The interfacial free energy seems to be one of the driving forces to denaturate proteins on polymers.

  10. The radiation inactivation of glutamate and isocitrate dehydrogenases

    International Nuclear Information System (INIS)

    El Failat, R.R.A.

    1980-12-01

    The reaction of free radicals produced by ionizing radiation with the enzymes glutamate dehydrogenase (GDH) and NADP + -specific isocitrate dehydrogenase (ICDH) have been studied by steady-state and pulse radiolysis techniques. In de-aerated GDH solutions, hydroxyl radicals have been found to be the most efficient of the primary radicals generated from water in causing inactivation. The effect of reaction with the enzyme of selective free radicals (SCN) 2 - , (Br) 2 - and (I) 2 - on its activity has also been studied. In neutral solutions, the order of inactivating effectiveness is (I) 2 - > (Br) 2 - > (SCN) 2 - . In the case of the thiocyanate radical anion (SCN) 2 - , the inactivation efficiency is found to depend on KSCN concentration. The radiation inactivation of GDH at both neutral and alkaline pH is accompanied by the loss of sulphydryl groups. Pulse radiolysis was also used to determine the rate constants and the transient absorption spectra following the reaction of the free radicals with GDH. 60 Co-γ-radiolysis and pulse radiolysis were also used to study the effect of ionizing radiation on the activity of ICDH. The results obtained were similar to those of GDH. (author)

  11. Amplification of oncogenes and integrated SV40 sequences in mammalian cells by the decay of incorporated iodine-125

    International Nuclear Information System (INIS)

    Ehrfeld, A.; Planas-Bohne, F.; Luecke-Huhle, C.

    1986-01-01

    Iodine-125, in the form of 5-[ 125 I]iododeoxyuridine (I-UdR), was incorporated into the DNA of SV40 transformed Chinese hamster embryo cells. Disintegration of the 125 I led to increased cell killing with increasing dose as measured by the colony-forming ability of single cells. The D37 (the dose at which 37% of the cells survive) amounts to 95 decays per cell, corresponding to 0.66 Gy. Variations in the copy number of specific DNA sequences was measured by using dispersed cell blotting with sensitive DNA hybridizations. A 13-fold amplification of the viral DNA sequences (SV40) and a twofold amplification of two cellular oncogenes of the ras-family (Ki-ras and Ha-ras) were found. Other cellular genes, like the alpha-actin gene, were not amplified, and no variation in gene copy number was detected after incubation of cells with cold I-UdR. We suggest the observed gene amplifications are induced by the densely ionizing radiation emitted by the decay of the incorporated 125 I atoms

  12. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

    Energy Technology Data Exchange (ETDEWEB)

    Su, L.-N.; Little, J.B. (Harvard School of Public Health, Boston, MA (United States))

    1992-08-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author).

  13. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

    International Nuclear Information System (INIS)

    Su, L.-N.; Little, J.B.

    1992-01-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author)

  14. Inactivation and stability of viral diagnostic reagents treated by gamma radiation

    International Nuclear Information System (INIS)

    White, L.A.; Freeman, C.Y.; Hall, H.E.; Forrester, B.D.

    1990-01-01

    The objective of this study was to apply the pertinent findings from gamma inactivation of virus infectivity to the production of high quality diagnostic reagents. A Gammacell 220 was used to subject 38 viruses grown in either susceptible tissue cultures or embryonated chicken eggs to various doses of gamma radiation from a cobalt-60 source. The radiation required to reduce viral infectivity was 0.42 to 3.7 megarads (Mrad). The effect of gamma treatment on the antigenic reactivity of reagents for the complement fixation (CF), hemagglutination (HA) and neuraminadase assays was determined. Influenza antigens inactivated with 1.7 Mrad displayed comparable potency, sensitivity, specificity and stability to those inactivated by standard procedures with beta-propiolactone (BPL). Significant inactivation of influenza N1 and B neuraminidase occurred with >2.4 Mrad radiation at temperatures above 4 0 C. All 38 viruses were inactivated, and CF or HA antigens were prepared successfully. Antigenic potency remained stable with all antigens for 3 years and with 83% after 5 years storage. Influenza HA antigens evaluated after 9 years of storage demonstrated 86% stability. Gamma radiation is safer than chemical inactivation procedures and is a reliable and effective replacement for BPL in preparing diagnostic reagents. (author)

  15. Inactivation and stability of viral diagnostic reagents treated by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    White, L A; Freeman, C Y; Hall, H E; Forrester, B D [Department of Health and Human Services, Atlanta, GA (USA)

    1990-10-01

    The objective of this study was to apply the pertinent findings from gamma inactivation of virus infectivity to the production of high quality diagnostic reagents. A Gammacell 220 was used to subject 38 viruses grown in either susceptible tissue cultures or embryonated chicken eggs to various doses of gamma radiation from a cobalt-60 source. The radiation required to reduce viral infectivity was 0.42 to 3.7 megarads (Mrad). The effect of gamma treatment on the antigenic reactivity of reagents for the complement fixation (CF), hemagglutination (HA) and neuraminadase assays was determined. Influenza antigens inactivated with 1.7 Mrad displayed comparable potency, sensitivity, specificity and stability to those inactivated by standard procedures with beta-propiolactone (BPL). Significant inactivation of influenza N1 and B neuraminidase occurred with >2.4 Mrad radiation at temperatures above 4{sup 0}C. All 38 viruses were inactivated, and CF or HA antigens were prepared successfully. Antigenic potency remained stable with all antigens for 3 years and with 83% after 5 years storage. Influenza HA antigens evaluated after 9 years of storage demonstrated 86% stability. Gamma radiation is safer than chemical inactivation procedures and is a reliable and effective replacement for BPL in preparing diagnostic reagents. (author).

  16. SV40 large T-p53 complex: evidence for the presence of two immunologically distinct forms of p53

    International Nuclear Information System (INIS)

    Milner, J.; Gamble, J.

    1985-01-01

    The transforming protein of SV40 is the large T antigen. Large T binds a cellular protein, p53, which is potentially oncogenic by virtue of its functional involvement in the control of cell proliferation. This raises the possibility that p53 may mediate, in part, the transforming function of SV40 large T. Two immunologically distinct forms of p53 have been identified in normal cells: the forms are cell-cycle dependent, one being restricted to nondividing cells (p53-Go) and the second to dividing cells (p53-G divided by). The authors have now dissociated and probed the multimeric complex of SV40 large T-p53 for the presence of immunologically distinct forms of p53. Here they present evidence for the presence of p53-Go and p53-G divided by complexed with SV40 large T

  17. One pyrimidine dimer inactivates expression of a transfected gene in xeroderma pigmentosum cells

    International Nuclear Information System (INIS)

    Protic-Sabljic, M.; Kraemer, K.H.

    1985-01-01

    The authors have developed a host cell reactivation assay of DNA repair utilizing UV-treated plasmid vectors. The assay primarily reflects cellular repair of transcriptional activity of damaged DNA measured indirectly as enzyme activity of the transfected genes. They studied three plasmids (pSV2cat, 5020 base pairs; pSV2catSVgpt, 7268 base pairs; and pRSVcat, 5027 base pairs) with different sizes and promoters carrying the bacterial cat gene (CAT, chloramphenicol acetyltransferase) in a construction that permits cat expression in human cells. All human simian virus 40-transformed cells studied expressed high levels of the transfected cat gene. UV treatment of the plasmids prior to transfection resulted in differential decrease in CAT activity in different cell lines. With pSV2catSVgpt, UV inactivation of CAT expression was greater in the xeroderma pigmentosum group A and D lines than in the other human cell lines tested. The D 0 of the CAT inactivation curve was 50 J X m-2 for pSV2cat and for pRSVcat in the xeroderma pigmentosum group A cells. The similarity of the D0 data in the xeroderma pigmentosum group A cells for three plasmids of different size and promoters implies they all have similar UV-inactivation target size. UV-induced pyrimidine dimer formation in the plasmids was quantified by assay of the number of UV-induced T4 endonuclease V-sensitive sites. In the most sensitive xeroderma pigmentosum cells, with all three plasmids, one UV-induced pyrimidine dimer inactivates a target of about 2 kilobases, close to the size of the putative CAT mRNA

  18. Inhibition of in vitro SV40 DNA replication by ultraviolet light

    International Nuclear Information System (INIS)

    Gough, G.; Wood, R.W.

    1989-01-01

    Ultraviolet light-induced DNA damage was found to inhibit SV40 origin-dependent DNA synthesis carried out by soluble humancell extracts. Replication of SV40-based plasmids was reduced to approx. 35% of that in unirradiated controls after irradiation with 50-100 J/m 2 germicidal ultraviolet light, where an average of 3-6 pyrimidine dimer photoproducts were formed per plasmid circle. Inhibition of the DNA helicase activity of T antigen (required for initiation of replication in the in vitro system) was also investigated, and was only significant after much higher fluences, 1000-5000 J/m 2 . The data indicate that DNA damage by ultraviolet light inhibits DNA synthesis in cell-free extracts principally by affecting components of the replication complex other than the DNA helicase activity of T antigen. The soluble system could be used to biochemically investigate the possible bypass or tolerance of DNA damage during replication (author). 21 refs.; 2 figs

  19. Hyperacetylation and differential deacetylation of histones H4 and H3 define two distinct classes of acetylated SV40 chromosomes early in infection

    International Nuclear Information System (INIS)

    Milavetz, Barry

    2004-01-01

    SV40 chromosomes undergoing encapsidation late in infection and SV40 chromatin in virions are hyperacetylated on histones H4 and H3. However, the fate of the SV40 chromosomes containing hyperacetylated histones in a subsequent round of infection has not been determined. In order to determine if SV40 chromosomes undergo changes in the extent of histone acetylation during early infection, we have analyzed SV40 chromosomes isolated 30 min and 3 h postinfection by quantitative ChIP assays, depletion ChIP assays, competitive ChIP assays, and ChIP assays combined with restriction endonuclease sensitivity using antibodies to hyperacetylated histones H4 and H3. We have shown that at 30 min postinfection, the hyperacetylated histones are associated with two distinct classes of SV40 chromosomes. One form is hyperacetylated specifically on histone H4 while a second form is hyperacetylated on both H4 and H3. Both forms of chromosomes appear to contain a nucleosome-free promoter region. Over the course of the next few hours of infection, the class of SV40 chromosomes hyperacetylated on only H4 is reduced or completely eliminated through deacetylation

  20. Inactivation of bacteria in sewage sludge by gamma radiation

    International Nuclear Information System (INIS)

    Pandya, G.A.; Kapila, Smita; Kelkar, V.B.; Negi, Shobha; Modi, V.V.

    1987-01-01

    The survival of certain bacterial cultures suspended in sewage sludge and exposed to gamma-radiation was studied. The inactivation patterns of most of the organisms were significantly different when irradiation was performed using sewage samples collected in the summer and monsoon seasons. The summer sample collected from the anaerobic digester afforded significant protection to both Gram negative and Gram positive organisms. This was evident by the increase in dose required to bring about a 6 log cycle reduction in viable count of the bacterial cultures, when suspended in sewage samples instead of phosphate buffer. The observations made using monsoon digester samples were quite different. This sewage sludge greatly enhanced inactivation by gamma-radiation in most cases. The effects of certain chemicals on the inactivation patterns of two organisms - Salmonella typhi and Shigella flexneri - were examined. Arsenate, mercury and lead salts sensitised S. typhi, while barium acetate and sodium sulphide protected this culture against gamma-radiation. In the case of Sh. flexneri, barium acetate and iodacetamide proved to be radioprotectors. The effects of some chemicals on the inactivation pattern of Sh. flexneri cells irradiated in sludge are also discussed. (author)

  1. Alterations of DNA content in human endometrial stromal cells transfected with a temperature-sensitive SV40: tetraploidization and physiological consequences.

    Science.gov (United States)

    Rinehart, C A; Mayben, J P; Butler, T D; Haskill, J S; Kaufman, D G

    1992-01-01

    The normal genomic stability of human cells is reversed during neoplastic transformation. The SV40 large T antigen alters the DNA content in human endometrial stromal cells in a manner that relates to neoplastic progression. Human endometrial stromal cells were transfected with a plasmid containing the A209 temperature-sensitive mutant of SV40 (tsSV40), which is also defective in the viral origin of replication. Ninety-seven clonal transfectants from seven different primary cell strains were isolated. Initial analysis revealed that 20% of the clonal populations (19/97) had an apparent diploid DNA content, 35% (34/97) had an apparent tetraploid DNA content, and the remainder were mixed populations of diploid and tetraploid cells. No aneuploid populations were observed. Diploid tsSV40 transformed cells always give rise to a population of cells with a tetraploid DNA content when continuously cultured at the permissive temperature. The doubling of DNA content can be vastly accelerated by the sudden reintroduction of large T antigen activity following a shift from non-permissive to permissive temperature. Tetraploid tsSV40 transfected cells have a lower capacity for anchorage-independent growth and earlier entry into 'crisis' than diploid cells. These results indicate that during the pre-crisis, extended lifespan phase of growth, the SV40 large T antigen causes a doubling of DNA content. This apparent doubling of DNA content does not confer growth advantage during the extended lifespan that precedes 'crisis'.

  2. The inactivation of papain by high LET radiations

    International Nuclear Information System (INIS)

    Bisby, R.H.; Cundall, R.B.; Sims, H.E.; Burns, W.G.

    1984-01-01

    The effect of varying LET over a wide range (0.2-1570 eV/nm) on the radiation-induced inactivation of the enzyme papain in dilute aqueous solution has been investigated. Measurements of total, reparable and non-reparable inactivation G values in oxygen, nitrous oxide and argon saturated solutions have allowed the contributions to inactivation from radicals and hydrogen peroxide to be evaluated. At high LET the results demonstrate an increasing component due to reaction of the superoxide radical, formed from oxygen produced in the track as a primary radiolysis product. This effect was not observed in our previous study with ribonuclease due to the insensitivity of ribonuclease to inactivation by superoxide and hydrogen peroxide. The results obtained with papain clearly demonstrate a maximum in G(H 2 O 2 ) at an LET of equivalent to 140 eV/nm. Generation of O 2 within the track as a primary radiolysis product at high LET now appears to be confirmed as an important mechanism leading to reduction in the oxygen enhancement ratio for cellular systems exposed to high LET radiations (Baverstock and Burns 1981). (author)

  3. Radiation protection guidelines for space missions

    International Nuclear Information System (INIS)

    Fry, R.J.; Nachtwey, D.S.

    1988-01-01

    The current radiation protection guidelines of the National Aeronautics and Space Administration (NASA) were recommended in 1970. The career limit was set at 4.0 Sv (400 rem). Using the same approach as in 1970 but current risk estimates, a considerably lower career limit would obtain today. Also, there is now much more information about the radiation environments that will be experienced in different missions. Furthermore, since 1970 women have joined the ranks of the astronauts. For these and other reasons, it was considered necessary to re-examine the radiation protection guidelines. This task has been undertaken by the National Council on Radiation Protection and Measurements Scientific Committee 75. Within the magnetosphere, the radiation environment varies with altitude and inclination of the orbit. In outer space missions, galactic cosmic rays, with the small but important heavy-ion component, determine the radiation environment. The new recommendations for career dose limits, based on lifetime excess risk of cancer mortality, take into account age at first exposure and sex. The career limits range from 1.0 Sv (100 rem) for a 24-y-old female up to 4.0 Sv (400 rem) for a 55-y-old male, compared with the previous single limit of 4.0 Sv (400 rem). The career limit for the lens of the eye has been reduced from 6.0 Sv (600 rem) to 4.0 Sv (400 rem)

  4. Effect of caffeine on the ultraviolet light induction of SV40 virus from transformed hamster cells

    International Nuclear Information System (INIS)

    Zamansky, G.B.; Kleinman, L.F.; Little, J.B.; Black, P.H.; Kaplan, J.C.

    1976-01-01

    The effect of caffeine on the uv light induction of SV40 virus from two transformed hamster cell lines heterogeneous for the induction of infectious virus was studied. The amount of virus induced was significantly increased in both cell lines when exposure to uv light was followed by treatment with caffeine. Caffeine in the absence of uv irradiation did not stimulate virus induction, nor did it stimulate SV40 replication in a lytic infection. There was an apparent difference in the concentrations of caffeine which maximally stimulated SV40 virus induction in the two cell lines. This effect could not be explained by differences in cell survival after exposure to uv light and caffeine. Since caffeine is known to cause the accumulation of gaps formed in DNA during postreplication repair of uv-irradiated rodent cells, our results support the hypothesis that the formation of gaps or breaks in DNA is an important early step in virus induction

  5. Functional size analysis of bioactive materials by radiation inactivation

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    1994-01-01

    When the research on various proteins including enzymes is carried out, first molecular weight is measured. The physical chemical methods used for measuring molecular weight cannot measure it in the state of actually acting in living bodies. Radiation inactivation method is the unique method which can measure the molecular weight of the active substances in living bodies. Paying attention to this point, recently it is attempted to measure the activity unit of enzymes, receptors and others, and to apply to the elucidation of their functions. In this report, the concept of the method of measuring molecular size based on radiation inactivation, the detailed experimental method and the points to which attention must be paid are described. Also its application to the elucidation of living body functions according to the example of the studies by the author is reported. The concept of the measurement of molecular weight by radiation inactivation is based on target theory. The preparation of samples, the effect of oxygen, radiation sources, dosimetry, irradiation temperature, internal standard process and so on are reported. The trend of the research is shown. (K.I.)

  6. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with SV40 T-antigen mutants defective in RB and P53 binding domains

    International Nuclear Information System (INIS)

    LingNah Su; Little, J.B.

    1992-01-01

    A series of human diploid fibroblast cell clones were developed by DNA transfection with either wild-type SV40 T-antigen (SV40T) or T-antigen mutants defective in its various functional domains. Cell clones expressing the wild-type SV40 T were significantly radioresistant as compared with clones transfected with the neo gene only (D o 192 ± 13 vs 127 ± 19). This radioresistance persisted in post-crisis, immortalized cell lines. A series of mutants with point or deletion mutations within each functionally active domain of SV40 T were also examined for their ability to alter radiosensitivity and induce morphological transformation. Cell clones transfected with T-antigen mutants defective in nuclear localization or origin binding showed increased radioresistance similar to clones transfected with wild-type T-antigen, and expressed morphological changes characteristic of SV40 T-transfected cells. (author)

  7. Inactivation of B. Pumilus spores by combination hydrostatic pressure-radiation treatment of parenteral solutions

    International Nuclear Information System (INIS)

    Wills, P.A.

    1975-01-01

    Bacterial spores are inactivated by moderate hydrostatic pressures. The radiation dose required to sterilize radiation sensitive pharmaceuticals can be considerably reduced using a combination hydrostatic pressure-radiation treatment. This paper describes a combination pressure-radiation sterilization process using Bacillus pumilus spores suspended in water, 0.9% saline, and 5% dextrose solutions. The optimum temperatures for spore inactivation at 35 MPa and the degree of inactivation at 35, 70 and 105 MPa applied for times up to 100 min have been determined. Inactivation was greatest in saline and least in dextrose. Spores in dextrose were only slightly less radiation resistant than in saline or water. It was calculated that the radiation dose required for sterilization could be halved with appropriate compression treatment. Examples of combinations of pressure-radiation suitable for sterilization are given. One combination is compression at 105 MPa for 18 min for a dose of 1.25 Mrad. (author)

  8. Radiation inactivation analysis of enzymes. Effect of free radical scavengers on apparent target sizes

    International Nuclear Information System (INIS)

    Eichler, D.C.; Solomonson, L.P.; Barber, M.J.; McCreery, M.J.; Ness, G.C.

    1987-01-01

    In most cases the apparent target size obtained by radiation inactivation analysis corresponds to the subunit size or to the size of a multimeric complex. In this report, we examined whether the larger than expected target sizes of some enzymes could be due to secondary effects of free radicals. To test this proposal we carried out radiation inactivation analysis on Escherichia coli DNA polymerase I, Torula yeast glucose-6-phosphate dehydrogenase, Chlorella vulgaris nitrate reductase, and chicken liver sulfite oxidase in the presence and absence of free radical scavengers (benzoic acid and mannitol). In the presence of free radical scavengers, inactivation curves are shifted toward higher radiation doses. Plots of scavenger concentration versus enzyme activity showed that the protective effect of benzoic acid reached a maximum at 25 mM then declined. Mannitol alone had little effect, but appeared to broaden the maximum protective range of benzoic acid relative to concentration. The apparent target size of the polymerase activity of DNA polymerase I in the presence of free radical scavengers was about 40% of that observed in the absence of these agents. This is considerably less than the minimum polypeptide size and may reflect the actual size of the polymerase functional domain. Similar effects, but of lesser magnitude, were observed for glucose-6-phosphate dehydrogenase, nitrate reductase, and sulfite oxidase. These results suggest that secondary damage due to free radicals generated in the local environment as a result of ionizing radiation can influence the apparent target size obtained by this method

  9. SV40 Utilizes ATM Kinase Activity to Prevent Non-homologous End Joining of Broken Viral DNA Replication Products

    Science.gov (United States)

    Sowd, Gregory A.; Mody, Dviti; Eggold, Joshua; Cortez, David; Friedman, Katherine L.; Fanning, Ellen

    2014-01-01

    Simian virus 40 (SV40) and cellular DNA replication rely on host ATM and ATR DNA damage signaling kinases to facilitate DNA repair and elicit cell cycle arrest following DNA damage. During SV40 DNA replication, ATM kinase activity prevents concatemerization of the viral genome whereas ATR activity prevents accumulation of aberrant genomes resulting from breakage of a moving replication fork as it converges with a stalled fork. However, the repair pathways that ATM and ATR orchestrate to prevent these aberrant SV40 DNA replication products are unclear. Using two-dimensional gel electrophoresis and Southern blotting, we show that ATR kinase activity, but not DNA-PKcs kinase activity, facilitates some aspects of double strand break (DSB) repair when ATM is inhibited during SV40 infection. To clarify which repair factors associate with viral DNA replication centers, we examined the localization of DSB repair proteins in response to SV40 infection. Under normal conditions, viral replication centers exclusively associate with homology-directed repair (HDR) and do not colocalize with non-homologous end joining (NHEJ) factors. Following ATM inhibition, but not ATR inhibition, activated DNA-PKcs and KU70/80 accumulate at the viral replication centers while CtIP and BLM, proteins that initiate 5′ to 3′ end resection during HDR, become undetectable. Similar to what has been observed during cellular DSB repair in S phase, these data suggest that ATM kinase influences DSB repair pathway choice by preventing the recruitment of NHEJ factors to replicating viral DNA. These data may explain how ATM prevents concatemerization of the viral genome and promotes viral propagation. We suggest that inhibitors of DNA damage signaling and DNA repair could be used during infection to disrupt productive viral DNA replication. PMID:25474690

  10. SV40 utilizes ATM kinase activity to prevent non-homologous end joining of broken viral DNA replication products.

    Directory of Open Access Journals (Sweden)

    Gregory A Sowd

    2014-12-01

    Full Text Available Simian virus 40 (SV40 and cellular DNA replication rely on host ATM and ATR DNA damage signaling kinases to facilitate DNA repair and elicit cell cycle arrest following DNA damage. During SV40 DNA replication, ATM kinase activity prevents concatemerization of the viral genome whereas ATR activity prevents accumulation of aberrant genomes resulting from breakage of a moving replication fork as it converges with a stalled fork. However, the repair pathways that ATM and ATR orchestrate to prevent these aberrant SV40 DNA replication products are unclear. Using two-dimensional gel electrophoresis and Southern blotting, we show that ATR kinase activity, but not DNA-PK(cs kinase activity, facilitates some aspects of double strand break (DSB repair when ATM is inhibited during SV40 infection. To clarify which repair factors associate with viral DNA replication centers, we examined the localization of DSB repair proteins in response to SV40 infection. Under normal conditions, viral replication centers exclusively associate with homology-directed repair (HDR and do not colocalize with non-homologous end joining (NHEJ factors. Following ATM inhibition, but not ATR inhibition, activated DNA-PK(cs and KU70/80 accumulate at the viral replication centers while CtIP and BLM, proteins that initiate 5' to 3' end resection during HDR, become undetectable. Similar to what has been observed during cellular DSB repair in S phase, these data suggest that ATM kinase influences DSB repair pathway choice by preventing the recruitment of NHEJ factors to replicating viral DNA. These data may explain how ATM prevents concatemerization of the viral genome and promotes viral propagation. We suggest that inhibitors of DNA damage signaling and DNA repair could be used during infection to disrupt productive viral DNA replication.

  11. A model for the stepwise radiation inactivation of the alpha 2-dimer of Na,K-ATPase

    International Nuclear Information System (INIS)

    Norby, J.G.; Jensen, J.

    1989-01-01

    This study is a direct continuation of Jensen, J., and Norby. A new model in which we propose that the in situ organization of the Na,K-ATPase alpha-subunit is an alpha 2-dimer and which describes the stepwise degradation by radiation inactivation of this assembly is presented on the basis of the following findings. Radiation inactivation size for alpha-peptide integrity, normal nucleotide, vanadate and ouabain binding, and K-pNPPase activity is close to m(alpha) = 112 kDa; for Na-ATPase activity it is 135 kDa and for Na,K-ATPase activity it increases from 140 to about 195 kDa with increasing assay ATP concentration (equal to increasing average turnover). Normal Tl+ occlusion had the same radiation inactivation size as Vmax for Na,K-ATPase, i.e. about 195 kDa. The binding experiments disclosed radiation-produced molecules with active binding sites but with a lower than normal affinity. Radiation inactivation size for the total binding capacity of ADP and ouabain was therefore smaller than the size of an alpha-peptide, namely about 70 kDa, and for total Tl+ occlusion it was down to 40 kDa. We can explain all these observations by using a new approach to target size analysis and by assuming a dimeric organization of the alpha-subunit. Each alpha-peptide is degraded stepwise by first destruction of either a 42- or a 70-kDa domain, and the partly damaged peptide may retain biochemical activity. We conclude that there is no role for the beta-subunit in catalysis and that the alpha-peptide is organized as an alpha 2-dimer in the membrane with each alpha-subunit being able to perform complete catalytic cycles (and probably also active transport), provided that it is stabilized by an adjacent alpha-peptide or a sufficiently large fragment thereof

  12. A model for the stepwise radiation inactivation of the alpha 2-dimer of Na,K-ATPase

    Energy Technology Data Exchange (ETDEWEB)

    Norby, J.G.; Jensen, J. (Univ. of Aarhus (Denmark))

    1989-11-25

    This study is a direct continuation of Jensen, J., and Norby. A new model in which we propose that the in situ organization of the Na,K-ATPase alpha-subunit is an alpha 2-dimer and which describes the stepwise degradation by radiation inactivation of this assembly is presented on the basis of the following findings. Radiation inactivation size for alpha-peptide integrity, normal nucleotide, vanadate and ouabain binding, and K-pNPPase activity is close to m(alpha) = 112 kDa; for Na-ATPase activity it is 135 kDa and for Na,K-ATPase activity it increases from 140 to about 195 kDa with increasing assay ATP concentration (equal to increasing average turnover). Normal Tl+ occlusion had the same radiation inactivation size as Vmax for Na,K-ATPase, i.e. about 195 kDa. The binding experiments disclosed radiation-produced molecules with active binding sites but with a lower than normal affinity. Radiation inactivation size for the total binding capacity of ADP and ouabain was therefore smaller than the size of an alpha-peptide, namely about 70 kDa, and for total Tl+ occlusion it was down to 40 kDa. We can explain all these observations by using a new approach to target size analysis and by assuming a dimeric organization of the alpha-subunit. Each alpha-peptide is degraded stepwise by first destruction of either a 42- or a 70-kDa domain, and the partly damaged peptide may retain biochemical activity. We conclude that there is no role for the beta-subunit in catalysis and that the alpha-peptide is organized as an alpha 2-dimer in the membrane with each alpha-subunit being able to perform complete catalytic cycles (and probably also active transport), provided that it is stabilized by an adjacent alpha-peptide or a sufficiently large fragment thereof.

  13. Reconstitution of wild type viral DNA in simian cells transfected with early and late SV40 defective genomes.

    Science.gov (United States)

    O'Neill, F J; Gao, Y; Xu, X

    1993-11-01

    The DNAs of polyomaviruses ordinarily exist as a single circular molecule of approximately 5000 base pairs. Variants of SV40, BKV and JCV have been described which contain two complementing defective DNA molecules. These defectives, which form a bipartite genome structure, contain either the viral early region or the late region. The defectives have the unique property of being able to tolerate variable sized reiterations of regulatory and terminus region sequences, and portions of the coding region. They can also exchange coding region sequences with other polyomaviruses. It has been suggested that the bipartite genome structure might be a stage in the evolution of polyomaviruses which can uniquely sustain genome and sequence diversity. However, it is not known if the regulatory and terminus region sequences are highly mutable. Also, it is not known if the bipartite genome structure is reversible and what the conditions might be which would favor restoration of the monomolecular genome structure. We addressed the first question by sequencing the reiterated regulatory and terminus regions of E- and L-SV40 DNAs. This revealed a large number of mutations in the regulatory regions of the defective genomes, including deletions, insertions, rearrangements and base substitutions. We also detected insertions and base substitutions in the T-antigen gene. We addressed the second question by introducing into permissive simian cells, E- and L-SV40 genomes which had been engineered to contain only a single regulatory region. Analysis of viral DNA from transfected cells demonstrated recombined genomes containing a wild type monomolecular DNA structure. However, the complete defectives, containing reiterated regulatory regions, could often compete away the wild type genomes. The recombinant monomolecular genomes were isolated, cloned and found to be infectious. All of the DNA alterations identified in one of the regulatory regions of E-SV40 DNA were present in the recombinant

  14. Bioburden assessment and gamma radiation inactivation patterns in parchment documents

    International Nuclear Information System (INIS)

    Nunes, Inês; Mesquita, Nuno; Cabo Verde, Sandra; Carolino, Maria Manuela; Portugal, António; Botelho, Maria Luísa

    2013-01-01

    Parchment documents are part of our cultural heritage and, as historical artifacts that they are, should be preserved. The aim of this study was to validate an appropriate methodology to characterize the bioburden of parchment documents, and to assess the growth and gamma radiation inactivation patterns of the microbiota present in that material. Another goal was to estimate the minimum gamma radiation dose (D min ) to be applied for the decontamination of parchment as an alternative treatment to the current toxic chemical and non-chemical decontamination methods. Two bioburden assessment methodologies were evaluated: the Swab Method (SM) and the Destructive Method (DM). The recovery efficiency of each method was estimated by artificial contamination, using a Cladosporium cladosporioides spore suspension. The parchment samples' microbiota was typified using morphological methods and the fungal isolates were identified by ITS-DNA sequencing. The inactivation pattern was assessed using the DM after exposure to different gamma radiation doses, and using C. cladosporioides as reference. Based on the applied methodology, parchment samples presented bioburden values lower than 5×10 3 CFU/cm 2 for total microbiota, and lower than 10 CFU/cm 2 for fungal propagules. The results suggest no evident inactivation trend for the natural parchment microbiota, especially regarding the fungal community. A minimum gamma radiation dose (D min ) of 5 kGy is proposed for the decontamination treatment of parchment. Determining the minimal decontamination dose in parchment is essential for a correct application of gamma radiation as an alternative decontamination treatment for this type of documents avoiding the toxicity and the degradation promoted by the traditional chemical and non-chemical treatments. - Highlights: • Characterization of the microbial population of parchment documents. • Study the inactivation pattern of parchment microbiota by gamma radiation. • Assessment of

  15. Validation of γ-radiation and ultraviolet as a new inactivators for foot and mouth disease virus in comparison with the traditional methods

    Science.gov (United States)

    Mahdy, Safy El din; Hassanin, Amr Ismail; Gamal El-Din, Wael Mossad; Ibrahim, Ehab El-Sayed; Fakhry, Hiam Mohamed

    2015-01-01

    Aim: The present work deals with different methods for foot and mouth disease virus (FMDV) inactivation for serotypes O/pan Asia, A/Iran05, and SAT-2/2012 by heat, gamma radiation, and ultraviolet (UV) in comparison with the traditional methods and their effects on the antigenicity of viruses for production of inactivated vaccines. Materials and Methods: FMDV types O/pan Asia, A/Iran05, and SAT-2/2012 were propagated in baby hamster kidney 21 (BHK21) and titrated then divided into five parts; the first part inactivated with heat, the second part inactivated with gamma radiation, the third part inactivated with UV light, the fourth part inactivated with binary ethylamine, and the last part inactivated with combination of binary ethylamine and formaldehyde (BEI+FA). Evaluate the method of inactivation via inoculation in BHK21, inoculation in suckling baby mice and complement fixation test then formulate vaccine using different methods of inactivation then applying the quality control tests to evaluate each formulated vaccine. Results: The effect of heat, gamma radiation, and UV on the ability of replication of FMDV “O/pan Asia, A/Iran05, and SAT-2/2012” was determined through BHK cell line passage. Each of the 9 virus aliquots titer 108 TCID50 (3 for each strain) were exposed to 37, 57, and 77°C for 15, 30, and 45 min. Similarly, another 15 aliquots (5 for each strain) contain 1 mm depth of the exposed samples in petri-dish was exposed to UV light (252.7 nm wavelength: One foot distance) for 15, 30, 45, 60, and 65 min. Different doses of gamma radiation (10, 20, 25, 30, 35, 40, 45, 50, 55, and 60 KGy) were applied in a dose rate 0.551 Gy/s for each strain and repeated 6 times for each dose. FMDV (O/pan Asia, A/Iran05, and SAT-2/2012) were inactivated when exposed to heat ≥57°C for 15 min. The UV inactivation of FMDV (O/pan Asia and SAT-2) was obtained within 60 min and 65 min for type A/Iran05. The ideal dose for inactivation of FMDV (O/pan Asia, A/Iran05

  16. Validation of γ-radiation and ultraviolet as a new inactivators for foot and mouth disease virus in comparison with the traditional methods

    Directory of Open Access Journals (Sweden)

    Safy El din Mahdy

    2015-09-01

    Full Text Available Aim: The present work deals with different methods for foot and mouth disease virus (FMDV inactivation for serotypes O/pan Asia, A/Iran05, and SAT-2/2012 by heat, gamma radiation, and ultraviolet (UV in comparison with the traditional methods and their effects on the antigenicity of viruses for production of inactivated vaccines. Materials and Methods: FMDV types O/pan Asia, A/Iran05, and SAT-2/2012 were propagated in baby hamster kidney 21 (BHK21 and titrated then divided into five parts; the first part inactivated with heat, the second part inactivated with gamma radiation, the third part inactivated with UV light, the fourth part inactivated with binary ethylamine, and the last part inactivated with combination of binary ethylamine and formaldehyde (BEI+FA. Evaluate the method of inactivation via inoculation in BHK21, inoculation in suckling baby mice and complement fixation test then formulate vaccine using different methods of inactivation then applying the quality control tests to evaluate each formulated vaccine. Results: The effect of heat, gamma radiation, and UV on the ability of replication of FMDV "O/pan Asia, A/Iran05, and SAT-2/2012" was determined through BHK cell line passage. Each of the 9 virus aliquots titer 108 TCID50 (3 for each strain were exposed to 37, 57, and 77°C for 15, 30, and 45 min. Similarly, another 15 aliquots (5 for each strain contain 1 mm depth of the exposed samples in petri-dish was exposed to UV light (252.7 nm wavelength: One foot distance for 15, 30, 45, 60, and 65 min. Different doses of gamma radiation (10, 20, 25, 30, 35, 40, 45, 50, 55, and 60 KGy were applied in a dose rate 0.551 Gy/s for each strain and repeated 6 times for each dose. FMDV (O/pan Asia, A/Iran05, and SAT-2/2012 were inactivated when exposed to heat ≥57°C for 15 min. The UV inactivation of FMDV (O/pan Asia and SAT-2 was obtained within 60 min and 65 min for type A/Iran05. The ideal dose for inactivation of FMDV (O/pan Asia, A

  17. Linear energy transfer (LET) effects in the radiation-induced inactivation of papain

    International Nuclear Information System (INIS)

    Bisby, R.H.; Cundall, R.B.; Sims, H.E.; Burns, W.G.

    1977-01-01

    The inactivation of dilute aqueous solutions of papain by radiations of varying linear energy transfer has been studied in N 2 , N 2 0 and O 2 -saturated solutions. The results obtained with low LET radiation are very similar to those previously reported by Lin et al (Radiation Res.;62:438(1975)). The additional data obtained at higher LET, when radical product yields are reduced and the yield of hydrogen peroxide is increased, show that the hydrogen atom is more important in the inactivation of papain than previously considered. (author)

  18. Inactivation of rabies diagnostic reagents by gamma radiation

    International Nuclear Information System (INIS)

    Gamble, W.C.; Chappell, W.A.; George, E.H.

    1980-01-01

    Treatment of CVS-11 rabies adsorbing suspensions and street rabies infected mouse brains with gamma radiation resulted in inactivated reagents that are safer to distribute and use. These irradiated reagents were as sensitive and reactive as the nonirradiated control reagents

  19. Gene expression promoted by the SV40 DNA targeting sequence and the hypoxia-responsive element under normoxia and hypoxia

    Directory of Open Access Journals (Sweden)

    C.B. Sacramento

    2010-08-01

    Full Text Available The main objective of the present study was to find suitable DNA-targeting sequences (DTS for the construction of plasmid vectors to be used to treat ischemic diseases. The well-known Simian virus 40 nuclear DTS (SV40-DTS and hypoxia-responsive element (HRE sequences were used to construct plasmid vectors to express the human vascular endothelial growth factor gene (hVEGF. The rate of plasmid nuclear transport and consequent gene expression under normoxia (20% O2 and hypoxia (less than 5% O2 were determined. Plasmids containing the SV40-DTS or HRE sequences were constructed and used to transfect the A293T cell line (a human embryonic kidney cell line in vitro and mouse skeletal muscle cells in vivo. Plasmid transport to the nucleus was monitored by real-time PCR, and the expression level of the hVEGF gene was measured by ELISA. The in vitro nuclear transport efficiency of the SV40-DTS plasmid was about 50% lower under hypoxia, while the HRE plasmid was about 50% higher under hypoxia. Quantitation of reporter gene expression in vitro and in vivo, under hypoxia and normoxia, confirmed that the SV40-DTS plasmid functioned better under normoxia, while the HRE plasmid was superior under hypoxia. These results indicate that the efficiency of gene expression by plasmids containing DNA binding sequences is affected by the concentration of oxygen in the medium.

  20. Complicated biallelic inactivation of Pten in radiation-induced mouse thymic lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Yu [Department of Biology, Graduate School of Science, Chiba University, Yayoicho, Inage-ku, Chiba 263-8522 (Japan); Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Takabatake, Takashi; Kakinuma, Shizuko; Amasaki, Yoshiko; Nishimura, Mayumi; Imaoka, Tatsuhiko; Yamauchi, Kazumi; Shang, Yi [Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Miyoshi-Imamura, Tomoko [Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Genetic Counseling Program, Graduate School of Humanities and Sciences, Ochanomizu University, 2-1-1 Otsuka, Bunkyou-ku, Tokyo 112-8610 (Japan); Nogawa, Hiroyuki [Department of Biology, Graduate School of Science, Chiba University, Yayoicho, Inage-ku, Chiba 263-8522 (Japan); Kobayashi, Yoshiro [Department of Biomolecular Science, Faculty of Science, Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510 (Japan); Shimada, Yoshiya, E-mail: y_shimad@nirsgo.jp [Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2010-04-01

    Inactivation of the phosphatase and tensin homolog gene (Pten) occurs via multiple tissue-dependent mechanisms including epigenetic silencing, point mutations, insertions, and deletions. Although frequent loss of heterozygosity around the Pten locus and plausible involvement of epigenetic silencing have been reported in radiation-induced thymic lymphomas, the proportion of lymphomas with inactivated Pten and the spectrum of causal aberrations have not been extensively characterized. Here, we assessed the mode of Pten inactivation by comprehensive analysis of the expression and alteration of Pten in 23 radiation-induced thymic lymphomas developed in B6C3F1 mice. We found no evidence for methylation-associated silencing of Pten; rather, complex structural abnormalities comprised of missense and nonsense mutations, 1- and 3-bp insertions, and focal deletions were identified in 8 of 23 lymphomas (35%). Sequencing of deletion breakpoints suggested that aberrant V(D)J recombination and microhomology-mediated rearrangement were responsible for the focal deletions. Seven of the 8 lymphomas had biallelic alterations, and 4 of them did not express Pten protein. These Pten aberrations coincided with downstream Akt phosphorylation. In conclusion, we demonstrate that Pten inactivation is frequently biallelic and is caused by a variety of structural abnormalities (rather than by epigenetic silencing) and is involved in radiation-induced lymphomagenesis.

  1. The mechanism of thioacetamide-induced apoptosis in the L37 albumin-SV40 T-antigen transgenic rat hepatocyte-derived cell line occurs without DNA fragmentation.

    Science.gov (United States)

    Bulera, S J; Sattler, C A; Gast, W L; Heath, S; Festerling, T A; Pitot, H C

    1998-10-01

    The hepatotoxicant thioacetamide (TH) has classically been used as a model to study hepatic necrosis; however, recent studies have shown that TH can also induce apoptosis. In this report we demonstrate that 2.68+/-0.54% of the albumin-SV40 T-antigen transgenic rat hepatocytes undergo TH-induced apoptosis, a level comparable to other in vivo models of liver apoptosis. In addition, TH could induce apoptosis and necrosis in the L37 albumin-SV40 T-antigen transgenic rat liver-derived cell line. Examination of dying L37 cells treated with 100 mM TH by electron microscopy revealed distinct morphological characteristics that could be attributed to apoptosis. Quantitation of apoptosis by FACS analysis 24 h after treatment with 100 mM TH revealed that 81.3+/-1.6% of the cells were undergoing apoptosis. In contrast, when L37 cells were treated with 250 mM TH, cells exhibited characteristics consistent with necrotic cell death. DNA fragmentation ladders were produced by growth factor withdrawal-induced apoptosis; however, in 100 mM TH-induced apoptosis, DNA fragmentation ladders were not observed. Analysis of endonuclease activity in L37 cells revealed that the enzymes were not inactivated in the presence of 100 mM TH. The data presented in this report indicate that the L37 cell line could be used to study the mechanism of TH-induced apoptosis that was not mediated through a mechanism requiring DNA fragmentation.

  2. Inactivation of the Radiation-Resistant Spoilage Bacterium Micrococcus radiodurans

    Science.gov (United States)

    Duggan, D. E.; Anderson, A. W.; Elliker, P. R.

    1963-01-01

    A simplified technique permitting the pipetting of raw puréed meats for quantitative bacteriological study is described for use in determining survival of these non-sporing bacteria, which are exceptionally resistant to radiation. Survival curves, using gamma radiation as the sterilizing agent, were determined in raw beef with four strains of Micrococcus radiodurans. Survival curves of the R1 strain in other meat substrates showed that survival was significantly greater in raw beef and raw chicken than in raw fish or in cooked beef. Resistance was lowest in the buffer. Cells grown in broth (an artificial growth medium) and resuspended in beef did not differ in resistance from cells that had been grown and irradiated in beef. Survival rate was statistically independent of the initial cell concentration, even though there appeared to be a correlation between lower death rate and lower initial cell concentrations. The initial viable count of this culture of the domesticated R1 strain in beef was reduced by a factor of about 10-5 by 3.0 megarad, and 4.0 megarad reduced the initial count by a factor of more than 10-9. Data suggest that M. radiodurans R1 is more resistant to radiation than spore-forming spoilage bacteria for which inactivation rates have been published. PMID:14063780

  3. SV40 late protein VP4 forms toroidal pores to disrupt membranes for viral release.

    Science.gov (United States)

    Raghava, Smita; Giorda, Kristina M; Romano, Fabian B; Heuck, Alejandro P; Hebert, Daniel N

    2013-06-04

    Nonenveloped viruses are generally released from the cell by the timely lysis of host cell membranes. SV40 has been used as a model virus for the study of the lytic nonenveloped virus life cycle. The expression of SV40 VP4 at later times during infection is concomitant with cell lysis. To investigate the role of VP4 in viral release and its mechanism of action, VP4 was expressed and purified from bacteria as a fusion protein for use in membrane disruption assays. Purified VP4 perforated membranes as demonstrated by the release of fluorescent markers encapsulated within large unilamellar vesicles or liposomes. Dynamic light scattering results revealed that VP4 treatment did not cause membrane lysis or change the size of the liposomes. Liposomes encapsulated with 4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-3-indacene-labeled streptavidin were used to show that VP4 formed stable pores in membranes. These VP4 pores had an inner diameter of 1-5 nm. Asymmetrical liposomes containing pyrene-labeled lipids in the outer monolayer were employed to monitor transbilayer lipid diffusion. Consistent with VP4 forming toroidal pore structures in membranes, VP4 induced transbilayer lipid diffusion or lipid flip-flop. Altogether, these studies support a central role for VP4 acting as a viroporin in the disruption of cellular membranes to trigger SV40 viral release by forming toroidal pores that unite the outer and inner leaflets of membrane bilayers.

  4. Radiation inactivation of multimeric enzymes: application to subunit interactions of adenylate cyclase

    International Nuclear Information System (INIS)

    Verkman, A.S.; Skorecki, K.L.; Ausiello, D.A.

    1986-01-01

    Radiation inactivation has been applied extensively to determine the molecular weight of soluble enzyme and receptor systems from the slope of a linear ln (activity) vs. dose curve. Complex nonlinear inactivation curves are predicted for multimeric enzyme systems, composed of distinct subunits in equilibrium with multimeric complexes. For the system A1 + A2----A1A2, with an active A1A2 complex (associative model), the ln (activity) vs. dose curve is linear for high dissociation constant, K. If a monomer, A1, has all the enzyme activity (dissociative model), the ln (activity) vs. dose curve has an activation hump at low radiation dose if the inactive subunit, A2, has a higher molecular weight than A1 and has upward concavity when A2 is smaller than A1. In general, a radiation inactivation model for a multistep mechanism for enzyme activation fulfills the characteristics of an associative or dissociative model if the reaction step forming active enzyme is an associative or dissociative reaction. Target theory gives the molecular weight of the active enzyme subunit or complex from the limiting slope of the ln (activity) vs. dose curve at high radiation dose. If energy transfer occurs among subunits in the multimer, the ln (activity) vs. dose curve is linear for a single active component and is concave upward for two or more active components. The use of radiation inactivation as a method to determine enzyme size and multimeric subunit assembly is discussed with specific application to the hormone-sensitive adenylate cyclase system. It is shown that the complex inactivation curves presented in the accompanying paper can be used select the best mechanism out of a series of seven proposed mechanisms for the activation of adenylate cyclase by hormone

  5. THE ANTIGENIC POTENCY OF EPIDEMIC INFLUENZA VIRUS FOLLOWING INACTIVATION BY ULTRAVIOLET RADIATION

    Science.gov (United States)

    Salk, Jonas E.; Lavin, G. I.; Francis, Thomas

    1940-01-01

    A study of the antigenic potency of influenza virus inactivated by ultraviolet radiation has been made. Virus so inactivated is still capable of functioning as an immunizing agent when given to mice by the intraperitoneal route. In high concentrations inactivated virus appears to be nearly as effective as active virus but when quantitative comparisons of the immunity induced by different dilutions are made, it is seen that a hundredfold loss in immunizing capacity occurs during inactivation. Virus in suspensions prepared from the lungs of infected mice is inactivated more rapidly than virus in tissue culture medium. A standard for the comparison of vaccines of epidemic influenza virus is proposed. PMID:19871057

  6. The analysis of radiation exposure of hospital radiation workers

    International Nuclear Information System (INIS)

    Jeong, Tae Sik; Shin, Byung Chul; Moon, Chang Woo; Cho, Yeong Duk; Lee, Yong Hwan; Yum, Ha Yong

    2000-01-01

    This investigation was performed in order to improve the health care of radiation workers, to predict a risk, to minimize the radiation exposure hazard to them and for them to realize radiation exposure danger when they work in radiation area in hospital. The documentations checked regularly for personal radiation exposure in four university hospitals in Pusan city in Korea between January 1, 1993 and December 31, 1997 were analyz ed. There were 458 persons in this documented but 111 persons who worked less then one year were excluded and only 347 persons were included in this study. The average of yearly radiation exposure of 347 persons was 1.52±1.35 mSv. Though it was less than 5OmSv, the limitaion of radiation in law but 125 (36%) people received higher radiation exposure than non-radiation workers. Radiation workers under 30 year old have received radiation exposure of mean 1.87±1.01 mSv/year, mean 1.22±0.69 mSv between 31 and 40 year old and mean 0.97±0.43 mSv/year over, 41year old (p<0.001). Men received mean 1.67±1.54 mSv/year were higher than women who received mean 1.13±0.61 mSv/year (p<0.01). Radiation exposure in the department of nuclear medicine department in spite of low energy sources is higher than other departments that use radiations in hospital (p<0.05). And the workers who received mean 3.69±1.81 mSv/year in parts of management of radiation sources and injection of sources to patient receive high radiation exposure in nuclear medicine department (0<0.01). In department of diagnostic radiology high radiation exposure is in barium enema rooms where workers received mean 3.74±1.74 mSv/year and other parts where they all use fluoroscopy such as angiography room of mean 1.17±0.35 mSv/year and upper gastrointestinal room of mean 1.74±1.34 mSv/year represented higher radiation exposure than average radiation exposure in diagnostic radiology (p<0.01). Doctors and radiation technologists received higher radiation exposure of each mean 1.75±1

  7. Radiation-induced inactivation of bovine liver catalase in nitrous oxide-saturated solutions

    International Nuclear Information System (INIS)

    Gebicka, L.; Metodiewa, D.

    1988-01-01

    Radiation-induced inactivation of catalase by . OH/H . radicals was studied. It was found that inactivation yield of catalase depended on the dose. Optical spectrum of irradiated catalase showed that no redox processes in active site of enzyme occurred as a result of . OH/H . interaction. (author) 19 refs.; 3 figs

  8. Arginine-rich cross-linking peptides with different SV40 nuclear localization signal content as vectors for intranuclear DNA delivery.

    Science.gov (United States)

    Bogacheva, Mariia; Egorova, Anna; Slita, Anna; Maretina, Marianna; Baranov, Vladislav; Kiselev, Anton

    2017-11-01

    The major barriers for intracellular DNA transportation by cationic polymers are their toxicity, poor endosomal escape and inefficient nuclear uptake. Therefore, we designed novel modular peptide-based carriers modified with SV40 nuclear localization signal (NLS). Core peptide consists of arginine, histidine and cysteine residues for DNA condensation, endosomal escape promotion and interpeptide cross-linking, respectively. We investigated three polyplexes with different NLS content (10 mol%, 50 mol% and 90 mol% of SV40 NLS) as vectors for intranuclear DNA delivery. All carriers tested were able to condense DNA, to protect it from DNAase I and were not toxic to the cells. We observed that cell cycle arrest by hydroxyurea did not affect transfection efficacy of NLS-modified carriers which we confirmed using quantitative confocal microscopy analysis. Overall, peptide carrier modified with 90 mol% of SV40 NLS provided efficient transfection and nuclear uptake in non-dividing cells. Thus, incorporation of NLS into arginine-rich cross-linking peptides is an adequate approach to the development of efficient intranuclear gene delivery vehicles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Radiation inactivation of T7 phage

    International Nuclear Information System (INIS)

    Becker, D.; Redpath, J.L.; Grossweiner, L.I.

    1978-01-01

    The radiation inactivation of T7 phage by 25-MeV electron pulses has been measured in various media containing a wide concentration range of radical scavenging solutes and in the presence of protective and sensitizing agents. The dependence of sensitivity on pulse dose, from 1 mrad to 3.6 krad, is attributed to radical depletion via bimolecular processes. The survival data are analyzed by extending target theory to include diffusive reactions of primary and secondary radicals generated in the medium. It is concluded that OH radicals are the principal primary inactivating species and that secondary radicals from Br - , CNS - , uracil, glucose, ribose, sucrose, tyrosine, and histidine are lethal to some extent. In nutrient broth or 100 mM histidine, psoralen derivatives, Actinomycin D, and Mitomycin C are anoxic sensitizers. It is proposed that the psoralens promote the formation of non-strand break lesions as the sensitization mechanism. The target theory based on diffusional kinetics is applicable to other systems including single cells

  10. Oncogenic transformation of rat lung epithelioid cells by SV40 DNA and restriction enzyme fragments

    International Nuclear Information System (INIS)

    Daya-Grosjean, L.; Lasne, C.; Nardeux, P.; Chouroulinkov, I.; Monier, R.

    1979-01-01

    Rat epithelioid lung cells were transformed with various preparations of SV40 DNA using the Ca 2+ -precipitation technique. The amount of SV40 genetic information integrated into transformed clones was evaluated by DNA-DNA renaturation kinetics. The growth properties on plastic and in soft-agar were examined, as well as the ability to induce tumors in syngeneic newborn animals or in adult nude mice. One particular transformed line, which had received the HpaII/BamHIA (59 per cent) fragment, was found to contain about 3 integrated copies of this fragment per cell and no significant amount of the HpaII/BamHIB (41 per cent fragment). This line which grew to high saturatio densities and efficiently formed clones in low serum on plastic, produced tumors in both syngeneic rats and nude mice. Thus the HpaII/BamHIA fragment, which mainly includes early viral information, was sufficient to impart these properties to rat epithelioid lung cells. (author)

  11. Inactivation of carotenoid-producing and albino strains of Neurospora crassa by visible light, blacklight, and ultraviolet radiation

    International Nuclear Information System (INIS)

    Blanc, P.L.; Tuveson, R.W.; Sargent, M.L.

    1976-01-01

    Suspensions of Neurospora crassa conidia were inactivated by blacklight (BL) radiation (300 to 425 nm) in the absence of exogenous photosensitizing compounds. Carotenoid-containing wild-type conidia were less sensitive to BL radiation than albino conidia, showing a dose enhancement factor (DEF) of 1.2 for dose levels resulting in less than 10 percent survival. The same strains were about equally sensitive to shortwave ultraviolet (uv) inactivation. The kinetics of BL inactivation are similar to those of photodynamic inactivation by visible light in the presence of a photosensitizing dye (methylene blue). Only limited inactivation by visible light in the absence of exogenous photosensitizers was observed. BL and UV inactivations are probably caused by different mechanisms since wild-type conidia are only slightly more resistant to BL radiation (DEF = 1.2 at 1.0 percent survival) than are conidia from a uv-sensitive strain (upr-1, uvs-3). The BL-induced lethal lesions are probably not cyclobutyl pyrimidine dimers since BL-inactivated Haemophilus influenzae transforming deoxyribonucleic acid is not photoreactivated by N. crassa wild-type enzyme extracts, whereas uv-inactivated transforming deoxyribonucleic acid is photoreactivable with this treatment

  12. Inactivation of poliovirus in wastewater sludge with radiation and thermoradiation

    International Nuclear Information System (INIS)

    Ward, R.L.

    1977-01-01

    The effect of sludge on the rate of viral inactivation by radiation and thermoradiation was determined. The virus used for the experiments was the poliovirus type 1 strain CHAT, which was grown in HeLa cells. Radiation, heat, and thermoradiation treatments were carried out in a chamber specifically designed to permit rapid heating and cooling of the samples at the beginning and completion of treatment, respectively. The treated samples were then assayed for plaque-forming units on HeLa cells after sonication in 0.1% sodium dodecylsulfate (SDS). For the radiation treatment virus was diluted 10-fold into PBS containing new sludge, irradiated at 20 0 C with 137 Cs at a dose rate of 30 krads/min, and assayed for infectious virus. The results show that raw sludge is protective of poliovirus against ionizing radiation but that small concentrations of sludge are nearly as protective as large concentrations. When heat and radiation are given simultaneously, however, the amount of protection afforded by sludge is less than the additive effects of the individual treatments. This result is especially evident at low concentrations of sludge. It appears, therefore, that thermoradiation treatment may be an effective way of inactivation viruses in waters containing low concentrations of suspended solids

  13. Characterization of the functional domains of the natriuretic peptide receptor/guanylate cyclase by radiation inactivation

    International Nuclear Information System (INIS)

    Tremblay, J.; Huot, C.; Koch, C.; Potier, M.

    1991-01-01

    Radiation inactivation has been used to evaluate the molecular size of domains responsible for atrial natriuretic peptide (ANP)-binding and cyclase functions of the ANP receptor/guanylate cyclase. Two types of inactivation curves were observed for cyclase function in both adrenal cortex and aortic smooth muscle cells: (1) biphasic with enhanced guanylate cyclase activity after exposure to low radiation doses and (2) linear after preincubation of membrane proteins with 0.5 microM ANP or solubilization with Triton X-100. The existence of an inhibitory component was the simplest model that best explained the types of radiation curves obtained. Activation of guanylate cyclase by ANP or Triton X-100 could occur via the dissociation of this inhibitory component from the catalytic domain. On the other hand, the loss of ANP-binding activity was linear with increasing radiation exposures under basal, ANP treatment, and Triton X-100 solubilization conditions. Radiation inactivation sizes of about 30 kDa for cyclase function, 20 kDa for ANP-binding function, and 90 kDa for inhibitory function were calculated. These studies suggest that the ANP receptor/guanylate cyclase behaves as a multidomain protein. The results obtained by radiation inactivation of the various biological functions of this receptor are compatible with the hypothesis of an intramolecular inhibitory domain repressing the guanylate cyclase catalytic domain within its membrane environment

  14. Attempts on producing lymphoid cell line from Penaeus monodon by induction with SV40-T and 12S EIA oncogenes.

    Science.gov (United States)

    Puthumana, Jayesh; Prabhakaran, Priyaja; Philip, Rosamma; Singh, I S Bright

    2015-12-01

    In an attempt of in vitro transformation, transfection mediated expression of Simian virus-40 (T) antigen (SV40-T) and transduction mediated expression of Adenovirus type 12 early region 1A (12S E1A) oncogene were performed in Penaeus monodon lymphoid cells. pSV3-neo vector encoding SV40-T oncogene and a recombinant baculovirus BacP2-12S E1A-GFP encoding 12S E1A oncogene under the control of hybrid promoters were used. Electroporation and lipofection mediated transformation of SV40-T in lymphoid cells confirmed the transgene expression by phenotypic variation and the expression of GFP in co-transfection experiment. The cells transfected by lipofection (≥ 5%) survived for 14 days with lower toxicity (30%), whilst on electroporation, most of the cells succumbed to death (60%) and survived cells lived up to 7 days. Transduction efficiency in primary lymphoid cells was more than 80% within 14 days of post-transduction, however, an incubation period of 7 days post-transduction was observed without detectable expression of 12S E1A. High level of oncogenic 12S E1A expression were observed after 14 day post-transduction and the proliferating cells survived for more than 90 days with GFP expression, however, without in vitro transformation and immortalization. The study put forth the requirement of transduction mediated 'specific' oncogene expression along with telomerase activation and epigenetic induction for the immortalization and establishment of shrimp cell line. Copyright © 2015. Published by Elsevier Ltd.

  15. pSv3neo transfection and radiosensitivity of human cancer cell lines

    International Nuclear Information System (INIS)

    Parris, C.N.; Masters, J.R.W.; Green, M.H.L.

    1990-01-01

    Immortalisation of human fibroblasts by transfection with a plasmid, pSV3neo, results in an increase in their radioresistance. The change in radiosensitivity may either be a consequence of transformation or due to expression of the SV40 T-antigen in pSV3neo. To investigate these two possibilities, we transfected pSV3neo into cells already transformed and immortalised. The radiosensitivies of three human bladder cancer cell lines were unaltered in clones expressing T-antigen, indicating that the changes observed in fibroblasts probably are a consequence of transformation, and not the presence of SV40 T-antigen. (author)

  16. Simvastatin (SV) metabolites in mouse tissues

    International Nuclear Information System (INIS)

    Duncan, C.A.; Vickers, S.

    1990-01-01

    SV, a semisynthetic analog of lovastatin, is hydrolyzed in vivo to its hydroxy acid (SVA), a potent inhibitor of HMG CoA reductase (HR). Thus SV lowers plasma cholesterol. SV is a substrate for mixed function oxidases whereas SVA undergoes lactonization and β-oxidation. Male CD-1 mice were dosed orally with a combination of ( 14 C)SV and ( 3 H)SVA at 25 mg/kg of each, bled and killed at 0.5, 2 and 4 hours. Labeled SV, SVA, 6'exomethylene SV (I), 6'CH 2 OH-SV (II), 6'COOH-SV (III) and a β-oxidized metabolite (IV) were assayed in liver, bile, kidneys, testes and plasma by RIDA. Levels of potential and active HR inhibitors in liver were 10 to 40 fold higher than in other tissues. II and III, in which the configuration at 6' is inverted, may be 2 metabolites of I. Metabolites I-III are inhibitors of HR in their hydroxy acid forms. Qualitatively ( 14 C)SV and ( 3 H)SVA were metabolized similarly (consistent with their proposed interconversion). However 3 H-SVA, I-III (including hydroxy acid forms) achieved higher concentrations than corresponding 14 C compounds (except in gall bladder bile). Major radioactive metabolites in liver were II-IV (including hydroxy acid forms). These metabolites have also been reported in rat tissues. In bile a large fraction of either label was unidentified polar metabolites. The presence of IV indicated that mice (like rats) are not good models for SV metabolism in man

  17. Monitoring ultraviolet (UV) radiation inactivation of Cronobacter sakazakii in dry infant formula using Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Liu, Qian; Lu, Xiaonan; Swanson, Barry G; Rasco, Barbara A; Kang, Dong-Hyun

    2012-01-01

    Cronobacter sakazakii is an opportunistic pathogen associated with dry infant formula presenting a high risk to low birth weight neonates. The inactivation of C. sakazakii in dry infant formula by ultraviolet (UV) radiation alone and combined with hot water treatment at temperatures of 55, 60, and 65 °C were applied in this study. UV radiation with doses in a range from 12.1 ± 0.30 kJ/m² to 72.8 ± 1.83 kJ/m² at room temperature demonstrated significant inactivation of C. sakazakii in dry infant formula (P radiation combining 60 °C hot water treatment increased inactivation of C. sakazakii cells significantly (P radiation on C. sakazakii inactivation kinetics (D value) were not observed in infant formula reconstituted in 55 and 65 °C water (P > 0.05). The inactivation mechanism was investigated using vibrational spectroscopy. Infrared spectroscopy detected significant stretching mode changes of macromolecules on the basis of spectral features, such as DNA, proteins, and lipids. Minor changes on cell membrane composition of C. sakazakii under UV radiation could be accurately and correctly monitored by infrared spectroscopy coupled with 2nd derivative transformation and principal component analysis. © 2011 Institute of Food Technologists®

  18. Pleomorphic adenoma cells vary in their susceptibility to SV40 transformation depending on the initial karyotype.

    Science.gov (United States)

    Kazmierczak, B; Thode, B; Bartnitzke, S; Bullerdiek, J; Schloot, W

    1992-07-01

    Chromosomal aberrations involving 8q12 or 12q13-15 characterize two cytogenetic subgroups of salivary gland pleomorphic adenomas. As the tumors of the two groups differ in their clinical and histologic characteristics, we decided to determine their susceptibility to SV40 transformation. We transfected cell cultures from 13 adenomas with aberrations involving 8q12 and from seven adenomas with involvement of 12q13-15 using an SV40 plasmid coding for the early region of the viral genome. Whereas all cultures with aberrations of 12q13-15 showed transformed foci, only 4 of the 13 cultures with 8q12 abnormalities showed foci of transformed cells. We also observed a much higher immortalization rate in the first group (3/7 vs. 1/13). All successfully transformed tumor cell cultures showed a relatively stable karyotype in the pre-crisis stage and a high mitotic index, were T-antigen positive, and had an extended life span in vitro.

  19. Radiation-induced gene amplification in rodent and human cells

    International Nuclear Information System (INIS)

    Luecke-Huhle, C.; Gloss, B.; Herrlich, P.

    1990-01-01

    Ionizing and UV radiations induce amplification of SV40 DNA sequences integrated in the genome of Chinese hamster cells and increase amplification of the dihydrofolate reductase (DHFR) gene during methotrexate selection in human skin fibroblasts of a patient with ataxia telangiectasia. Various types of external (60-Co-γ-rays, 241-Am-α-particles, UV) or internal radiation (caused by the decay of 125 I incorporated into DNA in form of I-UdR) were applied. By cell fusion experiments it could be shown that SV40 gene amplification is mediated by one or several diffusible trans-acting factors induced or activated in a dose dependent manner by all types of radiation. One of these factors binds to a 10 bp sequence within the minimal origin of replication of SV40. In vivo competition with an excess of a synthetic oligonucleotide comprising this sequence blocks radiation-induced amplification. (author) 25 refs.; 8 figs

  20. SV40 T antigen alone drives karyotype instability that precedes neoplastic transformation of human diploid fibroblasts.

    Science.gov (United States)

    Ray, F A; Peabody, D S; Cooper, J L; Cram, L S; Kraemer, P M

    1990-01-01

    To define the role of SV40 large T antigen in the transformation and immortalization of human cells, we have constructed a plasmid lacking most of the unique coding sequences of small t antigen as well as the SV40 origin of replication. The promoter for T antigen, which lies within the origin of replication, was deleted and replaced by the Rous sarcoma virus promoter. This minimal construct was co-electroporated into normal human fibroblasts of neonatal origin along with a plasmid containing the neomycin resistance gene (neo). Three G418-resistant, T antigen-positive clones were expanded and compared to three T antigen-positive clones that received the pSV3neo plasmid (capable of expressing large and small T proteins and having two origins of replication). Autonomous replication of plasmid DNA was observed in all three clones that received pSV3neo but not in any of the three origin minus clones. Immediately after clonal expansion, several parameters of neoplastic transformation were assayed. Low percentages of cells in T antigen-positive populations were anchorage independent or capable of forming colonies in 1% fetal bovine serum. The T antigen-positive clones generally exhibited an extended lifespan in culture but rarely became immortalized. Large numbers of dead cells were continually generated in all T antigen-positive, pre-crisis populations. Ninety-nine percent of all T antigen-positive cells had numerical or structural chromosome aberrations. Control cells that received the neo gene did not have an extended life span, did not have noticeable numbers of dead cells, and did not exhibit karyotype instability. We suggest that the role of T antigen protein in the transformation process is to generate genetic hypervariability, leading to various consequences including neoplastic transformation and cell death.

  1. p53 levels, cell cycle kinetics and radiosensitivity in two SV40 transformed Wi38VA13 fibroblast strains

    International Nuclear Information System (INIS)

    Werner, F.; Zoelzer, F.; Streffer, C.

    2001-01-01

    Background: The tumor suppressor protein p53 which can mediate an ionizing radiation-induced G 1 arrest in mammalian cells, forms complexes with SV40 large T antigen (l-T-Ag). We have analyzed the p53 levels, the capability to undergo a G 1 arrest and the radiosensitivity of two SV40 transformed fibroblast strains differing in their large T antigen expression. Material and Methods: One of the two strains (VA13F) is the commercially available form of Wi38VA13, the other (VA13E) arose spontaneously from the original one in our laboratory. Their p53 levels were measured by means of flow cytometry (FCM) and Western blot (WB) with two p53 antibodies (Ab-3, clone PAb240; Ab-6, clone DO-1; both Oncogene Science). Cell cycle distributions were determined flow cytometrically after BrdU labeling at regular time intervals after exposure to 250 kV X-rays. Radiosensitivity was assessed in a clonogenicity assay. Results: The p53 levels of the two strains corresponded to their large T antigen expression, presumably due to complex formation between the two proteins. The strain with a high p53 level did not show a G 1 arrest and had a relatively high radiosensitivity, whereas the strain with a low p53 level showed a significant G 1 arrest and a lower radiosensitivity. Conclusion: These results suggest that 1. complex formation between the large T antigen and p53 reduces the latter's functionality; 2. in these two strains the G 1 arrest is one of the factors determining radiosensitivity. (orig.) [de

  2. Functional size of vacuolar H+ pumps: Estimates from radiation inactivation studies

    International Nuclear Information System (INIS)

    Sarafian, V.; Poole, R.J.

    1991-01-01

    The PPase and the ATPase from red beet (Beta vulgaris) vacuolar membranes were subjected to radiation inactivation by a 60 Co source in both the native tonoplast and detergent-solubilized states, in order to determine their target molecular sizes. Analysis of the residual phosphohydrolytic and proton transport activities, after exposure to varying doses of radiation, yielded exponential relationships between the activities and radiation doses. The deduced target molecular sizes for PPase activity in native and solubilized membranes were 125kD and 259kD respectively and 327kD for H + -transport. This suggests that the minimum number of subunits of 67kD for PPi hydrolysis is two in the native state and four after Triton X-100 solubilization. At least four subunits would be required for H + -translocation. Analysis of the ATPase inactivation patterns revealed target sizes of 384kD and 495kD for ATP hydrolysis in native and solubilized tonoplast respectively and 430kD for H + -transport. These results suggest that the minimum size for hydrolytic or transport functions is relatively constant for the ATPase

  3. Use of ultraviolet radiation for inactivation of bacteria and coliphages in pretreated wastewater

    International Nuclear Information System (INIS)

    Dizer, H.; Bartocha, W.; Bartel, H.; Seidel, K.; Lopez-Pila, J.M.; Grohmann, A.

    1993-01-01

    The inactivation of bacteria and coliphages by u.v. radiation was tested in a full-scale pilot plant with a flow rate of 180 m 3 /h. The investigated water contained about 70% secondary effluent from sewage treatment plants and 30% surface water. The minimal rated radiation density was 13.3 mW/cm 2 (60% of u.v. transmission in water), and the radiation exposure lasted for 3.54 s resulting in a u.v. radiation dose of 47 mWs/cm 2 . This type of u.v. radiation chamber decreased the concentration of total coliform organisms, E. coli, fecal streptococci, Salmonella sp. and coliphages in the influent by 1–2 logs. Strains of bacteria, Streptococcus faecalis and Salmonella enteritidis, seeded artificially into the influent showed a reduction of about 2–4 logs after u.v. radiation. The coliphage f2 was more resistant than the tested bacteria and reduced by less than 2 logs through u.v. radiation. The inactivating effect of u.v. radiation was counteracted by the binding of the coliphage f2 to suspended turbid particles. It can be recommended to use u.v. treatment of effluents of wastewater plants after a flocculation and filtration step to improve the efficiency of the u.v. radiation. (author)

  4. Target size analysis of bioactive substances by radiation inactivation. Comparison with electron beam and. gamma. -ray

    Energy Technology Data Exchange (ETDEWEB)

    Kume, Tamikazu; Watanabe, Yuhei; Ishigaki, Isao; Hirose, Shigehisa

    1988-11-01

    The molecular sizes of various bioactive substances can be measured by the radiation inactivation method. The high energy electron beam (10 MeV) and /sup 60/Co-..gamma.. ray are mainly used for radiation inactivation method. When the practical electron accelerator (/similar to/ 3 MeV) is used for the method, the problems such as penetration and increase of temperature will arise. In this paper the radiation inactivation using 3MeV electron beam is investigated by comparison with ..gamma..-ray. When the plate type glass ampules (glass thickness 1 +- 0.1 mm) were used as the irradiation vessels, relatively uniform dose distribution was obtained. The temperature increased only from 21 degC to 35 degC by irradiation (0.77 mA, 100 passes, 100 kGy). Under the irradiation condition mentioned above, the molecular size of three enzymes were calculated from D/sub 37/ doses. The molecular sizes obtained by electron beam and ..gamma..-ray were 14,000 and 17,000 respectively for lysozyme, 33,000 for pepsin, and 191,000 and 164,000 for yeast alcohol dehydrogenase. These values agreed closely with the reported molecular weight, suggesting that the 3 MeV electron beam can also be used for the radiation inactivation under limited conditions.

  5. Radiation inactivation target size of rat adipocyte glucose transporters in the plasma membrane and intracellular pools

    International Nuclear Information System (INIS)

    Jacobs, D.B.; Berenski, C.J.; Spangler, R.A.; Jung, C.Y.

    1987-01-01

    The in situ assembly states of the glucose transport carrier protein in the plasma membrane and in the intracellular (microsomal) storage pool of rat adipocytes were assessed by studying radiation-induced inactivation of the D-glucose-sensitive cytochalasin B binding activities. High energy radiation inactivated the glucose-sensitive cytochalasin B binding of each of these membrane preparations by reducing the total number of the binding sites without affecting the dissociation constant. The reduction in total number of binding sites was analyzed as a function of radiation dose based on target theory, from which a radiation-sensitive mass (target size) was calculated. When the plasma membranes of insulin-treated adipocytes were used, a target size of approximately 58,000 daltons was obtained. For adipocyte microsomal membranes, we obtained target sizes of approximately 112,000 and 109,000 daltons prior to and after insulin treatment, respectively. In the case of microsomal membranes, however, inactivation data showed anomalously low radiation sensitivities at low radiation doses, which may be interpreted as indicating the presence of a radiation-sensitive inhibitor. These results suggest that the adipocyte glucose transporter occurs as a monomer in the plasma membrane while existing in the intracellular reserve pool either as a homodimer or as a stoichiometric complex with a protein of an approximately equal size

  6. Functional size of photosynthetic electron transport chain determined by radiation inactivation

    International Nuclear Information System (INIS)

    Pan, R.S.; Chen, L.F.; Wang, M.Y.; Tsal, M.Y.; Pan, R.L.; Hsu, B.D.

    1987-01-01

    Radiation inactivation technique was employed to determine the functional size of photosynthetic electron transport chain of spinach chloroplasts. The functional size for photosystem I+II(H 2 O to methylviologen) was 623 +/- 37 kilodaltons; for photosystem II (H 2 O to dimethylquinone/ferricyanide), 174 +/- 11 kilodaltons; and for photosystem I (reduced diaminodurene to methylviologen), 190 +/- 11 kilodaltons. The difference between 364 +/- 22 (the sum of 174 +/- 11 and 190 +/- 11) kilodaltons and 623 +/- 37 kilodaltons is partially explained to be due to the presence of two molecules of cytochrome b 6 /f complex of 280 kilodaltons. The molecular mass for other partial reactions of photosynthetic electron flow, also measured by radiation inactivation, is reported. The molecular mass obtained by this technique is compared with that determined by other conventional biochemical methods. A working hypothesis for the composition, stoichiometry, and organization of polypeptides for photosynthetic electron transport chain is proposed

  7. Protective effect by EDTA in radiation inactivation of enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Kumakura, M; Kaetsu, I

    1985-11-05

    Protective effect by EDTA in radiation inactivation of enzymes such as glucoamylase, cellulase, and urease was studied. A remarkable protective effect by EDTA was observed and had a maximum at certain EDTA concentration. The protective effect was compared with other protective agents in the irradiation of urease, in which the protective ability of EDTA was greater than those of sulfhydryl compounds such as cysteine. (author).

  8. Mechanisms of poliovirus inactivation by the direct and indirect effects of ionizing radiation

    International Nuclear Information System (INIS)

    Ward, R.L.

    1980-01-01

    This study was designed to measure the effects of ionizing radiation on poliovirus particles when given under conditions where either direct (in broth) or indirect (in water) effects were predominant. Under direct conditions, inactivation of poliovirus was found to be due primarily to RNA damage, although capsid damage could account for about one-third of the viral inactivation. RNA damage did not appear to be due to strand breakage and therefore was probably caused primarily by base damage or crosslink formation. Capsid damage under direct irradiation conditions did not result in significant alterations of either the sedimentation coefficients or the isoelectric points of the poliovirus particles or detectable modification of the sizes of the viral proteins. It did, however, cause loss of availability to bind to host cells. Under indirect conditions no more than 25% of viral inactivation appeared to be due to RNA damage. However, the sedimentation coefficients and isoelectric points of the viral particles were greatly altered, and their abilities to bind to cells were lost at about three-fourths the rate of loss of infectivity. Capsid damage in this case did result in changes in the sizes of capsid proteins. Therefore, the majority of the radiation inactivation under indirect conditions appeared to be due to protein damage

  9. Radiation inactivation analysis of assimilatory NADH:nitrate reductase. Apparent functional sizes of partial activities associated with intact and proteolytically modified enzyme

    International Nuclear Information System (INIS)

    Solomonson, L.P.; McCreery, M.J.; Kay, C.J.; Barber, M.J.

    1987-01-01

    Recently we demonstrated that target sizes for the partial activities of nitrate reductase were considerably smaller than the 100-kDa subunit which corresponded to the target size of the full (physiologic) activity NADH:nitrate reductase. These results suggested that the partial activities resided on functionally independent domains and that radiation inactivation may be due to localized rather than extensive damage to protein structure. The present study extends these observations and addresses several associated questions. Monophasic plots were observed over a wide range of radiation doses, suggesting a single activity component in each case. No apparent differences were observed over a 10-fold range of concentration for each substrate, suggesting that the observed slopes were not due to marked changes in Km values. Apparent target sizes estimated for partial activities associated with native enzyme and with limited proteolysis products of native enzyme suggested that the functional size obtained by radiation inactivation analysis is independent of the size of the polypeptide chain. The presence of free radical scavengers during irradiation reduced the apparent target size of both the physiologic and partial activities by an amount ranging from 24 to 43%, suggesting that a free radical mechanism is at least partially responsible for the inactivation. Immunoblot analysis of nitrate reductase irradiated in the presence of free radical scavengers revealed formation of distinct bands at 90, 75, and 40 kDa with increasing doses of irradiation rather than complete destruction of the polypeptide chain

  10. Disinfection of secondary effluent by gamma radiation inactivation efficiency and regrowth

    International Nuclear Information System (INIS)

    Sekiguchi, M.; Sawai, T.; Shimokawa, T.; Sawai, T.

    1992-01-01

    Inactivation efficiencies of several microorganisms in secondary effluents (SE) from sewage treatment plants by gamma radiation were investigated. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae inoculated in SE were very sensitive but Streptcoccus sp. was resistant to gamma radiation. In addition, no significant difference was found between the combined sewer system and the separate sewer system in regards to the inactivation efficiencies of the bacteria inoculated in the SE. The number of total bacteria in SE was rapidly decreased in the dose range of 0 to 0.2-0.3 kGy but the number gradually fell over the dose range. Moreover, the number of total coliforms almost exponentially decreased with increasing dose, and fell to undetectable levels at about 0.5 kGy. Because of the decrease of the initial bacteria number in SE, adequate filtrating treatments were effective in lowering the irradiation dose for disinfection. Further, the effects of filtrating treatment on bacteria regrowth in SE are discussed. (author)

  11. Photosensitized inactivation of DNA by monochromatic 334-nm radiation in the presence of 2-thiouracil: genetic activity and backbone breaks

    International Nuclear Information System (INIS)

    Peak, M.J.; Ito, A.; Peak, J.G.; Foote, C.S.

    1988-01-01

    Monochromatic 334-nm radiation delivered under aerobic conditions inactivates the genetic activity (ability to transform auxotrophic recipient cells to nutritional prototrophy) of isolated transforming Bacillus subtilis DNA. The presence of superoxide dismutase (SOD), catalase, and mannitol reduces the 334-nm inactivation. The rate of inactivation of the genetic activity by 334-nm radiation is enhanced fivefold by the sensitizer 2-thiouracil (s 2 Ura). This enhancement is substantially reversed when the irradiations are performed in the presence of mannitol, and, to a lesser extent, SOD. Catalase slightly reduces the s 2 Ura enhancement of 334-nm inactivation of transforming activity. Backbone breaks induced in the same DNA by aerobic 334-nm radiation were also enhanced markedly by the presence of s 2 Ura; this enhancement was reversed by the presence of mannitol and, to a lesser extent, SOD during irradiation. Catalase had no effect upon s 2 Ura-enhanced, 334-nm-induced SSBs. Whereas DNA breakage may be responsible for a portion of the inactivation of the DNA by the photosensitized reaction between s 2 Ura and 334-nm radiation, it is not the only inactivating lesion, because the yield of SSBs per lethal hit per unit length of DNA is not constant for all the irradiation conditions studied. (author)

  12. Induction of DNA double-strand breaks by ionizing radiation of different quality and their relevance for cell inactivation

    International Nuclear Information System (INIS)

    Kampf, G.

    1988-01-01

    By investigation of the production of DNA strand breaks and of DNA release from the nuclear membrane complex in Chinese hamster cells using different radiation qualities from 1 to 360 keV/μm, partly also under hypoxic conditions, and by relating the results to the induction of chromosome aberrations and to cell inactivation it has become possible to find connections between the induction of molecular lesions and the expression of this damage on the cellular level. From the studies follows that DNA pieces are cut off from the nuclear membrane complex by DNA double-strand breaks (DSB). The share and size of the released pieces depends on radiation dose and quality as well as on the oxygen conditions. The lesions can partly be repaired. In connection with the DSB rates the results of the DNA release studies led to the conclusion that the DNA in the cells must be organized in superstructure units (MASSUs) with a DNA mass of about 2 x 10 9 g/mol, which are associated to the nuclear membrane in attachment points. The numerical relations show that for a 37% survival probability about 90 DSB per genome are required with sparsely ionizing radiation; this number declines to about 40 by use of more densely ionizing radiation up to 150 keV/μm, and increases again with further rise of the ionization density. Hence, for cell inactivation not simply a certain number of DSB per cell is required but rather seems their cooperation within a small structure section of the DNA to be relevant. These critical structures are with high probability the MASSUs. An irrepairable release of DNA from such a structure unit can bring about a chromosome break detectable in the metaphase and finally lead to cell inactivation. DSB turned out to be the essential lethal events in bacteria as well. The relatively small differences to the eukaryotic cells in the position of the maximum of radiation sensitivity on the LET scale and in the lesion sensitivity towards DSB let suggest that a common critical

  13. Inactivation of human immunodeficiency virus (HIV) by ionizing radiation in body fluids and serological evidence

    International Nuclear Information System (INIS)

    Bigbee, P.D.; Sarin, P.S.; Humphreys, J.C.; Eubanks, W.G.; Sun, D.; Hocken, D.G.; Thornton, A.; Adams, D.E.; Simic, M.G.

    1989-01-01

    A method to use ionizing radiation to inactivate HIV (Human Immunodeficiency Virus) in human body fluids was studied in an effort to reduce the risk of accidental infection to forensic science laboratory workers. Experiments conducted indicate that an X-ray absorbed dose of 25 krad was required to completely inactivate HIV. This does not alter forensically important constituents such as enzymes and proteins in body fluids. This method of inactivation of HIV cannot be used on body fluids which will be subjected to deoxyribonucleic acid (DNA) typing

  14. Environmental radioactivity and radiation exposure in Switzerland 1993

    International Nuclear Information System (INIS)

    1994-01-01

    Systematic monitoring of radioactivity in the environment and food has been going on in Switzerland since the mid 1950s. This report contains a summary of the values measured in 1993, along with the interpretation of the data and the resultant radiation dose for the population. The monitoring programme deals with radioactivity in the atmosphere, precipitation, aquatic systems, grass, foodstuffs and the human body, but also includes natural radiation, doses due to radon inside dwellings, emissions from nuclear power stations and other radiation sources. With two exceptions, the nuclear power plants and other facilities licensed to handle radioactive substances remained within their annual release limits in 1993, and measurements carried out in the environment revealed no inadmissible radioactivity concentrations or dose values. The population's mean annual radiation dose totals 4 mSv. Some 40% of this is due to radon in the home, with a mean of 1.6 mSv and extreme values as high as around 100 mSv; 30% or 1.2 mSv, may be ascribed to natural radiation, leaving less then 0.2 mSv ascribable to man-made sources, excluding medical applications. (author) figs., tabs

  15. Comparative inactivation of enteric adenoviruses, poliovirus and coliphages by ultraviolet irradiation

    International Nuclear Information System (INIS)

    Meng, Q.S.; Gerba, C.P.

    1996-01-01

    The inactivation of enteric adenoviruses 40 and 41 by ultraviolet (UV) radiation was investigated and compared with poliovirus type 1 (strain LSc-2ab) and coliphages MS-2 and PRD-1. Purified stocks of the viruses were exposed to collimated ultraviolet radiation in a stirred reactor for a total dose of up to 140 mW s/cm 2 . The doses of UV to achieve a 90% inactivation of adenovirus 40, adenovirus 41, coliphages MS-2 and PRD-1 and poliovirus type 1 were 30, 23.6, 14, 8.7 and 4.1 mW s/cm 2 , respectively. Adenovirus 40 was significantly more resistant than coliphage MS-2 to UV irradiation (P < 0.01). Adenovirus 41 appeared slightly more sensitive than adenovirus 40, but the difference was not significant (P>0.05). The resistance of PRD-1 was less than MS-2 (P < 0.01), but greater than poliovirus type 1 (P < 0.01). Adenoviruses 40 and 41 were more resistant than Bacillus subtilis spores, often suggested as an indicator of UV light performance. The double-stranded DNA adenoviruses appear to be the most resistant of all potentially water-borne enteric viruses to UV light disinfection. (author)

  16. STX140, but not paclitaxel, inhibits mammary tumour initiation and progression in C3(1/SV40 T/t-antigen transgenic mice.

    Directory of Open Access Journals (Sweden)

    Florence Meyer-Losic

    Full Text Available Despite paclitxael's clinical success, treating hormone-refractory breast cancer remains challenging. Paclitaxel has a poor pharmacological profile, characterized by a low therapeutic index (TIX caused by severe dose limiting toxicities, such as neutropenia and peripheral neuropathy. Consequently, new drugs are urgently required. STX140, a compound previously shown to have excellent efficacy against many tumors, is here compared to paclitaxel in three translational in vivo breast cancer models, a rat model of peripheral neuropathy, and through pharmacological testing. Three different in vivo mouse models of breast cancer were used; the metastatic 4T1 orthotopic model, the C3(1/SV40 T-Ag model, and the MDA-MB-231 xenograft model. To determine TIX and pharmacological profile of STX140, a comprehensive dosing regime was performed in mice bearing MDA-MD-231 xenografts. Finally, peripheral neuropathy was examined using a rat plantar thermal hyperalgesia model. In the 4T1 metastatic model, STX140 and paclitaxel significantly inhibited primary tumor growth and lung metastases. All C3(1/SV40 T-Ag mice in the control and paclitaxel treated groups developed palpable mammary cancer. STX140 blocked 47% of tumors developing and significantly inhibited growth of tumors that did develop. STX140 treatment caused a significant (P<0.001 survival advantage for animals in early and late intervention groups. Conversely, in C3(1/SV40 T-Ag mice, paclitaxel failed to inhibit tumor growth and did not increase survival time. Furthermore, paclitaxel, but not STX140, induced significant peripheral neuropathy and neutropenia. These results show that STX140 has a greater anti-cancer efficacy, TIX, and reduced neurotoxicity compared to paclitaxel in C3(1/SV40 T-Ag mice and therefore may be of significant benefit to patients with breast cancer.

  17. Membrane-bound Na,K-ATPase: target size and radiation inactivation size of some of its enzymatic reactions

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, J.; Norby, J.G.

    1988-12-05

    Frozen samples of membrane-bound pig kidney Na,K-ATPase were subjected to target size analysis by radiation inactivation with 10-MeV electrons at -15 degrees C. The various properties investigated decreased monoexponentially with radiation dose, and the decay constants, gamma, were independent of the presence of other proteins and of sucrose concentrations above 0.25 M. The temperature factor was the same as described by others. Irradiation of four proteins of known molecular mass, m, showed that gamma for protein integrity was proportional to m with a proportionality factor about 20% higher than that conventionally used. By this standard curve, glucose-6-phosphate dehydrogenase activity used as internal standard gave a radiation inactivation size of 110 +/- 5 kDa, very close to m = 104-108 kDa for the dimer, as expected. For Na+/K+-transporting ATPase the following target sizes and radiation inactivation size values were very close to m = 112 kDa for the alpha-peptide: peptide integrity of alpha, 115 kDa; unmodified binding sites for ATP and vanadate, 108 kDa; K+-activated p-nitrophenylphosphatase activity, 106 kDa. There was thus no sign of dimerization of the alpha-peptide or involvement of the beta-peptide. In contrast, optimal Na+/K+-transporting ATPase activity had a radiation inactivation size = 189 +/- 7 kDa, and total nucleotide binding capacity corresponded to 72 +/- 3 kDa. These latter results will be extended and discussed in a forthcoming paper.

  18. Membrane-bound Na,K-ATPase: target size and radiation inactivation size of some of its enzymatic reactions

    International Nuclear Information System (INIS)

    Jensen, J.; Norby, J.G.

    1988-01-01

    Frozen samples of membrane-bound pig kidney Na,K-ATPase were subjected to target size analysis by radiation inactivation with 10-MeV electrons at -15 degrees C. The various properties investigated decreased monoexponentially with radiation dose, and the decay constants, gamma, were independent of the presence of other proteins and of sucrose concentrations above 0.25 M. The temperature factor was the same as described by others. Irradiation of four proteins of known molecular mass, m, showed that gamma for protein integrity was proportional to m with a proportionality factor about 20% higher than that conventionally used. By this standard curve, glucose-6-phosphate dehydrogenase activity used as internal standard gave a radiation inactivation size of 110 +/- 5 kDa, very close to m = 104-108 kDa for the dimer, as expected. For Na+/K+-transporting ATPase the following target sizes and radiation inactivation size values were very close to m = 112 kDa for the alpha-peptide: peptide integrity of alpha, 115 kDa; unmodified binding sites for ATP and vanadate, 108 kDa; K+-activated p-nitrophenylphosphatase activity, 106 kDa. There was thus no sign of dimerization of the alpha-peptide or involvement of the beta-peptide. In contrast, optimal Na+/K+-transporting ATPase activity had a radiation inactivation size = 189 +/- 7 kDa, and total nucleotide binding capacity corresponded to 72 +/- 3 kDa. These latter results will be extended and discussed in a forthcoming paper

  19. Promotion of initiated cells by radiation-induced cell inactivation.

    Science.gov (United States)

    Heidenreich, W F; Paretzke, H G

    2008-11-01

    Cells on the way to carcinogenesis can have a growth advantage relative to normal cells. It has been hypothesized that a radiation-induced growth advantage of these initiated cells might be induced by an increased cell replacement probability of initiated cells after inactivation of neighboring cells by radiation. Here Monte Carlo simulations extend this hypothesis for larger clones: The effective clonal expansion rate decreases with clone size. This effect is stronger for the two-dimensional than for the three-dimensional situation. The clones are irregular, far from a circular shape. An exposure-rate dependence of the effective clonal expansion rate could come in part from a minimal recovery time of the initiated cells for symmetric cell division.

  20. Defective repair of UV-damaged DNA in human tumor and SV40-transformed human cells but not in adenovirus-transformed human cells

    International Nuclear Information System (INIS)

    Rainbow, A.J.

    1989-01-01

    The DNA repair capacities of five human tumor cell lines, one SV40-transformed human cell line and one adenovirus-transformed human cell line were compared with that of normal human fibroblasts using a sensitive host cell reactivation (HCR) technique. Unirradiated and UV-irradiated suspensions of adenovirus type 2 (Ad 2) were assayed for their ability to form viral structural antigens (Vag) in the various cell types using immunofluorescent staining. The survival of Vag formation for UV-irradiated Ad 2 was significantly reduced in all the human tumor cell lines and the SV40-transformed human line compared to the normal human fibroblasts, but was apparently normal in the adenovirus-transformed human cells. D 0 values for the UV survival of Ad 2 Vag synthesis in the tumor and virally transformed lines expressed as a percentage of that obtained on normal fibroblast strains were used as a measure of DNA repair capacity. Percent HCR values ranged from 26 to 53% in the tumor cells. These results indicate a deficiency in the repair of UV-induced DNA damage associated with human tumorigenesis and the transformation of human cells by SV40 but not the transformation of human cells by adenovirus. (author)

  1. Functional significance of the oligomeric structure of the Na,K-pump from radiation inactivation and ligand binding

    International Nuclear Information System (INIS)

    Norby, J.G.; Jensen, J.

    1991-01-01

    The present article is concerned with the oligomeric structure and function of the Na,K-pump (Na,K-ATPase). The questions we have addressed, using radiation inactivation and target size analysis as well as ligand binding, are whether the minimal structural unit and the functional unit have more than one molecule of the catalytic subunit, alpha. The authors first discuss the fundamentals of the radiation inactivation method and emphasize the necessity for rigorous internal standardization with enzymes of known molecular mass. They then demonstrate that the radiation inactivation of Na,K-ATPase is a stepwise process which leads to intermediary fragments of the alpha-subunit with partial catalytic activity. From the target size analysis it is most likely that the membrane-bound Na,K-ATPase is structurally organized as a diprotomer containing two alpha-subunits. Determination of ADP- and ouabain-binding site stoichiometry favors a theory with one substrate site per (alpha beta) 2. 47 references

  2. Gamma radiation inactivation of pathogens in sludge under larger-scale condition

    Energy Technology Data Exchange (ETDEWEB)

    Sermkiattipong, N; Pongpat, S

    1996-12-01

    The effect of gamma radiation on microorganisms in sludge from Huay Kwang Sewage Treatment Plant and Vajira Hospital showed that total bacterial counts were reduced to 2-3 log cycles and 1-2 log cycles at 5 kGy irradiation with and without aeration, respectively. Inactivation of coliform bacteria in sludge required irradiation with and without aeration at the dosages of 3-4.5 and 4-5 kGy, respectively. A dose of 2-3 kGy was sufficient to inactivate fecal coliform bacteria and E. coli. The doses used for inactivation these bacteria depend on the irradiation condition and solid content in sludge sample. Irradiation with aeration led to an increased microbial inactivation. According to our results, the frequency of occurrence of salmonella e contaminated in sludge from Huay Kwang Sewage Treatment Plant and Vajira Hospital was 50% and 75%, respectively. A dose of 2 kGy irradiation with or without aeration, salmonella e could not be detected in any sludge. Clostridium perfringens organisms were also detected in non-irradiated and irradiated sludge from both sources. Moreover, a dose of 5 kGy irradiation with or without aeration was not enough to eliminate C. perfringens. However, no shigella e were isolated from any treatment of sludge

  3. Gamma radiation inactivation of pathogens in sludge under larger-scale condition

    International Nuclear Information System (INIS)

    Sermkiattipong, N.; Pongpat, S.

    1996-01-01

    The effect of gamma radiation on microorganisms in sludge from Huay Kwang Sewage Treatment Plant and Vajira Hospital showed that total bacterial counts were reduced to 2-3 log cycles and 1-2 log cycles at 5 kGy irradiation with and without aeration, respectively. Inactivation of coliform bacteria in sludge required irradiation with and without aeration at the dosages of 3-4.5 and 4-5 kGy, respectively. A dose of 2-3 kGy was sufficient to inactivate fecal coliform bacteria and E. coli. The doses used for inactivation these bacteria depend on the irradiation condition and solid content in sludge sample. Irradiation with aeration led to an increased microbial inactivation. According to our results, the frequency of occurrence of salmonella e contaminated in sludge from Huay Kwang Sewage Treatment Plant and Vajira Hospital was 50% and 75%, respectively. A dose of 2 kGy irradiation with or without aeration, salmonella e could not be detected in any sludge. Clostridium perfringens organisms were also detected in non-irradiated and irradiated sludge from both sources. Moreover, a dose of 5 kGy irradiation with or without aeration was not enough to eliminate C. perfringens. However, no shigella e were isolated from any treatment of sludge

  4. Inactivation of certain insect pathogens by ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, A.; Groener, A.; Huber, J.; Zimmermann, G.

    1981-01-01

    The UV-sensitivity of two baculoviruses (granulosis virus, nuclear polyhedrosis virus) and two entomopathogenic microorganisms (Bacillus thuringiensis, Beauveria bassiana) was determined by radiation tests. In the far UV (254 nm) the stability, measured at an inactivation rate of 99%, was in declining order: nuclear polyhedra >= conidia of B. bassiana > granula > spores of B. thuringiensis >= vegetative cells of B. thuringiensis. In the near UV (285-380 nm) the following order could be found: conidia of B. bassiana >= nuclear polyhedra > spores of B. thuringiensis >= granula > vegetative cells of B. thuringiensis. Far UV had a much higher germicidal effect for all pathogens tested than near UV.

  5. SvABA

    DEFF Research Database (Denmark)

    Wala, Jeremiah A; Bandopadhayay, Pratiti; Greenwald, Noah

    2018-01-01

    Structural variants (SVs), including small insertion and deletion variants (indels), are challenging to detect through standard alignment-based variant calling methods. Sequence assembly offers a powerful approach to identifying SVs, but is difficult to apply at scale genome-wide for SV detection...... due to its computational complexity and the difficulty of extracting SVs from assembly contigs. We describe SvABA, an efficient and accurate method for detecting SVs from short-read sequencing data using genome-wide local assembly with low memory and computing requirements. We evaluated Sv...... complex somatic rearrangements with chains of short (applied SvABA to 344 cancer genomes from 11 cancer types and found that short templated-sequence insertions occur in ∼4% of all somatic rearrangements. Finally, we...

  6. The inactivation of hepatitis A virus and other model viruses by UV irradiation

    International Nuclear Information System (INIS)

    Battigelli, D.A.; Sobsey, M.D.; Lobe, D.C.

    1993-01-01

    Ultraviolet light is an attractive alternative to chemical disinfection of water, but little is known about its ability to inactivate important waterborne pathogens such as hepatitis A virus. Therefore, the sensitivity of HAV strain HM-175, coxsackievirus type B-5, rotavirus strain SA-11, and bacteriophages MS2 and φX174 to ultraviolet radiation of 254 nm wavelength in phosphate buffered water was determined. Purified stocks of the viruses were combined and exposed to collimated UV radiation in a stirred reactor for a total dose of up to 40 mW sec/cm 2 . Virus survival kinetics were determined from samples removed at dose intervals. The results of these experiments indicate that UV radiation can effectively inactivate viruses of public health concern in drinking water. (author)

  7. Transcriptional repression is epigenetically marked by H3K9 methylation during SV40 replication

    OpenAIRE

    Kallestad, Les; Christensen, Kendra; Woods, Emily; Milavetz, Barry

    2014-01-01

    Background We have recently shown that T-antigen binding to Site I results in the replication-dependent introduction of H3K9me1 into SV40 chromatin late in infection. Since H3K9me2 and H3K9me3 are also present late in infection, we determined whether their presence was also related to the status of ongoing transcription and replication. Transcription was either inhibited with 5,6-dichloro-1-beta-D-ribofuranosylbenzimidizole (DRB) or stimulated with sodium butyrate and the effects on histone m...

  8. Radiation exposure to staff involved in diagnostic and therapeutic nuclear medicine procedures in some hospitals in Sudan

    International Nuclear Information System (INIS)

    Salih, Lamia Hamza Bashir

    2015-05-01

    Study was performed to evaluate radiation dose to staff involved in nuclear medicine procedures in some hospitals in Sudan. 15 radiation workers were studied in three hospitals. Radiation dose was measured using personal dose equivalent Hp (10), using calibrated electronic personal dosimeters (EPDs) worn on the chest and read at the end of the day. Staff doses were monitored in each hospital for a period of four weeks, The measured monthly Hp(10) values to staff ranged between 82.96-83.94μSv (to nurses), 38.81-53.97 μSv (to pharmacists), 16.87-70.21μSv (to technologists), 40.22-76.56μSv (to medical physicists). These mean monthly radiation doses were projected to the annual radiation doses received by the staff. The mean monthly radiation doses were projected to the annual radiation doses were found to be between ranges (185.57-923.34μSv/y). Results found showed that there was no dose that exceeded the limits of annual dose recommended for workers by International Commission on Radiology Protection (ICRP) (20 mSv/year). This study is expected to increase the awareness of staff about the radiation hazards and protection.(Author)

  9. Radiation inactivation method provides evidence that membrane-bound mitochondrial creatine kinase is an oligomer

    International Nuclear Information System (INIS)

    Quemeneur, E.; Eichenberger, D.; Goldschmidt, D.; Vial, C.; Beauregard, G.; Potier, M.

    1988-01-01

    Lyophilized suspensions of rabbit heart mitochondria have been irradiated with varying doses of gamma rays. Mitochondrial creatine kinase activity was inactivated exponentially with a radiation inactivation size of 352 or 377 kDa depending upon the initial medium. These values are in good agreement with the molecular mass previously deduced from by permeation experiments: 357 kDa. This is the first direct evidence showing that the native form of mitochondrial creatine kinase is associated to the inner membrane as an oligomer, very likely an octamer

  10. Research And Investigation To Establish The Database Of Environment Radiation Background For Vietnam (Phase 2009 -2011)

    International Nuclear Information System (INIS)

    Trinh Van Giap; Nguyen Huu Quyet; Nguyen Quang Long; Bui Dac Dung; Vuong Thu Bac; Le Dinh Cuong; Chu Vu Long; Le Ngoc Thiem; Truong Y; Nguyen Van Mai; Nguyen Ba Tien

    2013-01-01

    Setting up data base of natural radiation background serves for planning socio-economics development in a province as well as the whole country and estimating annual effective dose of population. Beside external irradiation dose caused by the natural radioisotopes in the series 238 U, 232 Th and 40 K in soil, population has been received internal dose caused by the above radioisotopes taken in the body from several ways. In order to complete the database of national radiation background and go to estimate annual effective radiation dose of population in the whole country, this project focus to carry out the works as following: (i) Setting up database of radiation background in the whole country: 150 soil samples that collected in the districts of 46 provinces have been analyzed. The average activity concentration of 238 U, 232 Th and 40 K are 37.86 Bq/kg, 58.88 Bq/kg and 462.78 Bq/kg, respectively. The outdoor, indoor and total annual effective doses are calculated: 0.087±0.036 mSv; 0.488±0.202 mSv and 0.576± 0.240 mSv, respectively. (ii) Setting up database of radiation background of province Ninh Thuan and Quang Nam: The detailed database of radiation background of all villages in Ninh Thuan and Quang Nam has been established. 84 soil samples in Ninh Thuan and 311 in Quang Nam were collected for analyze. The indoor and outdoor radon concentration at sampling positions has been measured. The average activities of 238 U, 232 Th, 40 K, and 222 Rn isotopes in Ninh Thuan are reported: 33.50 Bq/kg, 55.43 Bq/kg, 701.12 Bq/kg and 12.1 Bq/m 3 , 9.5 Bq/m 3 , respectively. The outdoor, indoor and total annual effective doses in Ninh Thuan are calculated: 0.095±0.029 mSv; 0.529±0.162 mSv and 0.624± 0.382 mSv, respectively. The average activities of 238 U, 232 Th, 40 K, and 222 Rn isotopes in Quang Nam are reported: 44.47 Bq/kg, 52.68 Bq/kg, 459.33 Bq/kg, 18.0 Bq/m 3 . The outdoor, indoor and total annual effective doses are calculated: 0.086±0.039 mSv; 0.482±0.216 mSv

  11. Inactivation of certain insect pathogens by ultraviolet radiation

    International Nuclear Information System (INIS)

    Krieg, A.; Groener, A.; Huber, J.; Zimmermann, G.

    1981-01-01

    The UV-sensitivity of two baculoviruses (granulosis virus, nuclear polyhedrosis virus) and two entomopathogenic microorganisms (Bacillus thuringiensis, Beauveria bassiana) was determined by radiation tests. In the far UV (254 nm) the stability, measured at an inactivation rate of 99%, was in declining order: nuclear polyhedra >= conidia of B. bassiana > granula > spores of B. thuringiensis >= vegetative cells of B. thuringiensis. In the near UV (285-380 nm) the following order could be found: conidia of B. bassiana >= nuclear polyhedra > spores of B. thuringiensis >= granula > vegetative cells of B. thuringiensis. Far UV had a much higher germicidal effect for all pathogens tested than near UV. (orig.) [de

  12. Radiation inactivation of Paenibacillus larvae and sterilization of American Foul Brood (AFB) infected hives using Co-60 gamma rays

    International Nuclear Information System (INIS)

    De Guzman, Zenaida M.; Cervancia, Cleofas R.; Dimasuay, Kris Genelyn B.; Tolentino, Mitos M.; Abrera, Gina B.; Cobar, Ma. Lucia C.; Fajardo, Alejandro C.; Sabino, Noel G.; Manila-Fajardo, Analinda C.; Feliciano, Chitho P.

    2011-01-01

    The effectiveness of gamma radiation in inactivating the Philippine isolate of Paenibacillus larvae was investigated. Spores of P. larvae were irradiated at incremental doses (0.1, 0.2, 0.4, 0.8 and 1.6 kGy) of gamma radiation emitted by a 60 Co source. Surviving spores were counted and used to estimate the decimal reduction (D 10 ) value. A dose of 0.2 kGy was sufficient to inactivate 90% of the total recoverable spores from an initial count of 10 5 -9x10 3 spores per glass plate. The sterilizing effect of high doses of gamma radiation on the spores of P. larvae in infected hives was determined. In this study, a minimum dose (D min ) of 15 kGy was tested. Beehives with sub-clinical infections of AFB were irradiated and examined for sterility. All the materials were found to be free of P. larvae indicating its susceptibility to γ-rays. After irradiation, there were no visible changes in the physical appearance of the hives' body, wax and frames. Thus, a dose of 15 kGy is effective enough for sterilization of AFB-infected materials. - Highlights: → We characterized Paenibacillus larvae and determined its radiation sensitivity. → We investigated the effectiveness of gamma rays in inactivating P. larvae. → Gamma radiation inactivates P. larvae. → 15 kGy is effective for the sterilization of P. larvae-infected hives. → Irradiation produces no visible changes in the hives' body, waxes and frames.

  13. Cell inactivation by heavy charged particles

    Energy Technology Data Exchange (ETDEWEB)

    Blakely, E A [Lawrence Berkeley Lab., CA (United States). Cell and Molecular Biology Div.

    1992-06-01

    The inactivation of cells resulting in lethal or aberrant effects by charged particles is of growing interest. Charged particles at extremely high LET are capable of completely eliminating cell-type and cell-line differences in repair capacity. It is still not clear however whether the repair systems are inactivated, or merely that heavy-ion lesions are less repairable. Studies correlating the particle inactivation dose of radioresistant cells with intact DNA analyzed with pulse field gel electrophoresis and other techniques may be useful, but more experiments are also needed to assess the fidelity of repair. For particle irradiations between 40-100 keV/{mu}m there is however evidence for particle-induced activation of specific genes in mammalian cells, and certain repair processes in bacteria. New data are available on the inactivation of developmental processes in several systems including seeds, and cells of the nematode C. elegans. Future experimental and theoretical modeling research emphasis should focus on exploring particle-induced inactivation of endpoints assessing functionality and not just lethality, and on analyzing molecular damage and genetic effects arising in damage but non-inactivated survivors. The discrete nature of selective types of particle damage as a function of radiation quality indicates the value of accelerated ions as probes of normal and aberrant biological processes. Information obtained from molecular analyses of damage and repair must however be integrated into the context of cellular and tissue functions of the organism. (orig.).

  14. Homologous SV40 RNA trans-splicing: Special case or prime example of viral RNA trans-splicing?

    Directory of Open Access Journals (Sweden)

    Sushmita Poddar

    2014-06-01

    Full Text Available To date the Simian Virus 40 (SV40 is the only proven example of a virus that recruits the mechanism of RNA trans-splicing to diversify its sequences and gene products. Thereby, two identical viral transcripts are efficiently joined by homologous trans-splicing triggering the formation of a highly transforming 100 kDa super T antigen. Sequences of other viruses including HIV-1 and the human adenovirus type 5 were reported to be involved in heterologous trans-splicing towards cellular or viral sequences but the meaning of these events remains unclear. We computationally and experimentally investigated molecular features associated with viral RNA trans-splicing and identified a common pattern: Viral RNA trans-splicing occurs between strong cryptic or regular viral splice sites and strong regular or cryptic splice sites of the trans-splice partner sequences. The majority of these splice sites are supported by exonic splice enhancers. Splice sites that could compete with the trans-splicing sites for cis-splice reactions are weaker or inexistent. Finally, all but one of the trans-splice reactions seem to be facilitated by one or more complementary binding domains of 11 to 16 nucleotides in length which, however occur with a statistical probability close to one for the given length of the involved sequences. The chimeric RNAs generated via heterologous viral RNA trans-splicing either did not lead to fusion proteins or led to proteins of unknown function. Our data suggest that distinct viral RNAs are highly susceptible to trans-splicing and that heterologous viral trans-splicing, unlike homologous SV40 trans-splicing, represents a chance event.

  15. recA+-dependent inactivation of the lambda repressor in Escherichia coli lysogens by γ-radiation and by tif expression

    International Nuclear Information System (INIS)

    West, S.C.; Powell, K.A.; Emmerson, P.T.

    1975-01-01

    When lambda lysogens of E. coli are induced by γ-radiation the lambda repressor, as measured by its specific binding to lambda DNA, is rapidly inactivated by a recA + -dependent process which does not require new protein synthesis. This rapid inactivation is similar to inactivation of repressor by expression of the temperature sensitive E. coli mutation tif. In contrast, induction by UV irradiation or mitomycin C treatment requires new protein synthesis and there is a lag before the repressor is inactivated (Tomizawa and Ogawa, 1967; Shinagawa and Itoh, 1973). (orig.) [de

  16. The inactivation of hepatitis A virus and other model viruses by UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Battigelli, D A; Sobsey, M D; Lobe, D C [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Environmental Sciences

    1993-01-01

    Ultraviolet light is an attractive alternative to chemical disinfection of water, but little is known about its ability to inactivate important waterborne pathogens such as hepatitis A virus. Therefore, the sensitivity of HAV strain HM-175, coxsackievirus type B-5, rotavirus strain SA-11, and bacteriophages MS2 and [phi]X174 to ultraviolet radiation of 254 nm wavelength in phosphate buffered water was determined. Purified stocks of the viruses were combined and exposed to collimated UV radiation in a stirred reactor for a total dose of up to 40 mW sec/cm[sup 2]. Virus survival kinetics were determined from samples removed at dose intervals. The results of these experiments indicate that UV radiation can effectively inactivate viruses of public health concern in drinking water. (author).

  17. Occupational radiation exposure in Germany in 2012. Report of the radiation protection register; Die berufliche Strahlenexposition in Deutschland 2012. Bericht des Strahlenschutzregisters

    Energy Technology Data Exchange (ETDEWEB)

    Frasch, Gerhard; Kammerer, Lothar; Karofsky, Ralf; Mordek, Else; Schlosser, Andrea; Spiesl, Josef

    2014-04-15

    In Germany, persons who are occupationally exposed to ionising radiation are monitored by several official dosimetry services that transmit the dose records about individual radiation monitoring to the Radiation Protection Register of the Federal Office for Radiation Protection (BfS). The purpose of the Radiation Protection Register is to supervise the keeping of the dose limits and to monitor the compliance with the radiation protection principle ''Optimisation'' by performing detailed annual statistical analyses of the monitored persons and their radiation exposure. The annual report of the Radiation Protection Register provides information about status and development of occupational radiation exposure in Germany. In 2012, about 350,000 workers were monitored with dosemeters for occupational radiation exposure. The number increased continuously by totally 10 % into the past five years. 19 % of the monitored persons received measurable personal doses. The average annual dose of these exposed workers was 0.52 mSv corresponding to 2.6 % of the annual dose limit of 20 mSv for radiation workers. In total, 2 persons exceeded the annual dose limit of 20 mSv, i.e. less than one case per 100,000 monitored persons. The collective dose of the monitored persons decreased to 27.9 Person-Sv, the lowest value since the last fifty years of occupational dose monitoring. 45 airlines calculated the route doses of 40,000 aircraft crew members by using certified computer programmes for dose calculation and sent the accumulated monthly doses via the Federal Office for Civil Aviation (''Luftfahrt-Bundesamt, LBA'') to the BfS. The collective dose of the aircraft crew personnel is 78.5 person- Sv, and thus significantly higher than the total collective dose of the workers monitored with personal dosemeters. The annual average dose of aircraft crew personnel was 1.96 mSv and decreased compared to 2011 (2.12 mSv) due to solar cycle. In 2012, about

  18. Irreversible inactivation of snake venom l-amino acid oxidase by covalent modification during catalysis of l-propargylglycine☆

    Science.gov (United States)

    Mitra, Jyotirmoy; Bhattacharyya, Debasish

    2013-01-01

    Snake venom l-amino acid oxidase (SV-LAAO, a flavor-enzyme) has attracted considerable attention due to its multifunctional nature, which is manifest in diverse clinical and biological effects such as inhibition of platelet aggregation, induction of cell apoptosis and cytotoxicity against various cells. The majority of these effects are mediated by H2O2 generated during the catalytic conversion of l-amino acids. The substrate analog l-propargylglycine (LPG) irreversibly inhibited the enzyme from Crotalus adamanteus and Crotalus atrox in a dose- and time-dependent manner. Inactivation was irreversible which was significantly protected by the substrate l-phenylalanine. A Kitz–Wilson replot of the inhibition kinetics suggested formation of reversible enzyme–LPG complex, which occurred prior to modification and inactivation of the enzyme. UV–visible and fluorescence spectra of the enzyme and the cofactor strongly suggested formation of covalent adduct between LPG and an active site residue of the enzyme. A molecular modeling study revealed that the FAD-binding, substrate-binding and the helical domains are conserved in SV-LAAOs and both His223 and Arg322 are the important active site residues that are likely to get modified by LPG. Chymotrypsin digest of the LPG inactivated enzyme followed by RP-HPLC and MALDI mass analysis identified His223 as the site of modification. The findings reported here contribute towards complete inactivation of SV-LAAO as a part of snake envenomation management. PMID:23772385

  19. Radiation inactivation of Paenibacillus larvae and sterilization of American Foul Brood (AFB) infected hives using Co-60 gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    De Guzman, Zenaida M. [Microbiological Research and Service Laboratory, Atomic Research Division, Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines); Cervancia, Cleofas R. [Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines, Los Banos, Laguna (Philippines); Dimasuay, Kris Genelyn B.; Tolentino, Mitos M.; Abrera, Gina B.; Cobar, Ma. Lucia C. [Microbiological Research and Service Laboratory, Atomic Research Division, Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines); Fajardo, Alejandro C.; Sabino, Noel G.; Manila-Fajardo, Analinda C. [Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines, Los Banos, Laguna (Philippines); Feliciano, Chitho P., E-mail: cpfeliciano@pnri.dost.gov.ph [Microbiological Research and Service Laboratory, Atomic Research Division, Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines); Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City (Philippines)

    2011-10-15

    The effectiveness of gamma radiation in inactivating the Philippine isolate of Paenibacillus larvae was investigated. Spores of P. larvae were irradiated at incremental doses (0.1, 0.2, 0.4, 0.8 and 1.6 kGy) of gamma radiation emitted by a {sup 60}Co source. Surviving spores were counted and used to estimate the decimal reduction (D{sub 10}) value. A dose of 0.2 kGy was sufficient to inactivate 90% of the total recoverable spores from an initial count of 10{sup 5}-9x10{sup 3} spores per glass plate. The sterilizing effect of high doses of gamma radiation on the spores of P. larvae in infected hives was determined. In this study, a minimum dose (D{sub min}) of 15 kGy was tested. Beehives with sub-clinical infections of AFB were irradiated and examined for sterility. All the materials were found to be free of P. larvae indicating its susceptibility to {gamma}-rays. After irradiation, there were no visible changes in the physical appearance of the hives' body, wax and frames. Thus, a dose of 15 kGy is effective enough for sterilization of AFB-infected materials. - Highlights: > We characterized Paenibacillus larvae and determined its radiation sensitivity. > We investigated the effectiveness of gamma rays in inactivating P. larvae. > Gamma radiation inactivates P. larvae. > 15 kGy is effective for the sterilization of P. larvae-infected hives. > Irradiation produces no visible changes in the hives' body, waxes and frames.

  20. Cryo-gamma radiation inactivation of bovine herpesvirus type-1

    Science.gov (United States)

    Degiorgi, C. Fernández; Smolko, E. E.; Lombardo, J. H.

    1999-07-01

    The radioresistance of bovine herpesvirus-1 (BHV-1), commonly known as infectious bovine rhinotracheitis virus (IBRV), suspended in free serum Glasgow-MEM medium and frozen at -78°C was studied. The number of surviving virus at a given dose of gamma-radiation was determined by a plaque assay system. D 10 values were calculated before and after removal of cell debris. The D 10 values obtained were 4.72 kGy and 7.31 kGy before and after removal of cell debris, respectively. Our results indicate that the inactivated viral particles could be used for vaccine preparation or diagnostic reagents.

  1. Sequence-selective topoisomerase II inhibition by anthracycline derivatives in SV40 DNA: Relationship with DNA binding affinity and cytotoxicity

    International Nuclear Information System (INIS)

    Capranico, G.; Kohn, K.W.; Pommier, Y.; Zunino, F.

    1990-01-01

    Topoisomerase II mediated double-strand breaks produced by anthracycline analogues were studied in SV40 DNA. The compounds included doxorubicin, daunorubicin, two doxorubicin stereoisomers (4'-epimer and β-anomer), and five chromophore-modified derivatives, with a wide range of cytotoxic activity and DNA binding affinity. Cleavage of 32 P-end-labeled DNA fragments was visualized by autoradiography of agarose and polyacrylamide gels. Structure-activity relationships indicated that alterations in the chromophore structure greatly affected drug action on topoisomerase II. In particular, removal of substituents on position 4 of the D ring resulted in more active inducers of cleavage with lower DNA binding affinity. The stereochemistry between the sugar and the chromophore was also essential for activity. All the active anthracyclines induced a single region of prominent cleavage in the entire SV40 DNA, which resulted from a cluster of sites between nucleotides 4237 and 4294. DNA cleavage intensity patterns exhibited differences among analogues and were also dependent upon drug concentration. Intensity at a given site dependent on both stimulatory and suppressive effects depending upon drug concentration and DNA sequence. A good correlation was found between cytotoxicity and intensity of topoisomerase II mediated DNA breakage

  2. Distribution of Radiation Exposure from Natural Radiation in Big Cities

    International Nuclear Information System (INIS)

    Udiyani, P.M.; Ahmad, Yus R.

    2000-01-01

    The measurement of radiation exposure from the natural radiation in the big city in Java such as Jakarta, Bandung, Semarang, Yogyakarta, and Surabaya have be done. Based on radiation dose and population at the sample location, the dose collective and risk probability will be know. The maximal exposure at Yogyakarta is 0.291 mSv/year and the minimal exposure at Surabaya is 0.216 mSv/year. Collective dose at Jakarta is 1.649.526 men mSv/year; Bandung 124.844 men mSv/year; Semarang : 64.558 men mSv/year; Yogyakarta 136.188 men mSv/year; and Surabaya 145.152 men mSv/year. The person probability of radiation disease at jakarta is 16.49 person/year, Bandung is 1.24 person/year, Semarang 1.64 person/year, Yogyakarta is 1.36 person/year, and Surabaya is 1.45 person/year

  3. Measurement and evaluation of the external radiation level at reactor Kartini

    International Nuclear Information System (INIS)

    Atok Suhartanto; Suparno

    2013-01-01

    Measurement and evaluation of external radiation level at reactor Kartini in 2012 has been done. The purpose of this activity is to know the external radiation level as a result of the radioactive or radiation source usage, toward the operational of limit condition. The measurement is using survey meter Inspector 11086, factor of calibration 0.991 mR/h, at 9 locations is: Control room area, Thermal column facilities, Demineralizer, Beamport radiography facilities, bulk shielding Deck, Subcritical facilities, Reactor hall, Deck reactor and on the surface of reactor water tank . The highest room average measurement result in 9 working areas for 12 months continuously are at the reactor tank location is between 13.05±1.09 (xlO -2 mSv/hour) to 16.80±1.40 (x10 -2 mSv/hour), and the lowest measurement result in 1 location (control room) is 0.02±0.005 (x10 -2 mSv/hour) to 0.035±0.009 (x10 -2 mSv/hour). The Kartini reactor is involved in the control area which has potentially contaminated and has radiation exposure at the level of 6 mSv/year. Radiation Protection Officer that work in interval will received radiation exposure dosage of 8.4 mSv/year. This dosage is still below the Below Dosage Value which is recommended by, BAPETEN decree No, 4, 2013 about Protection and Radiation Safety in Nuclear Energy Application at 20 mSv/year. The result of the evaluation above shows that the external radiation which occurred in each area is still below the operational of limit condition that is written on the Kartini reactor safety analysis report, on document number: C7/05/B2/LAK/2010, revision 7. So that the workplace is safe for work monitored. (author)

  4. Environmental Gamma Radiation Measurements in Baskil District

    International Nuclear Information System (INIS)

    Canbazoglu, C.

    2008-01-01

    In this study, we have determined environmental gamma radiation dose rate in Baskil district which has very high granite content in its geographical structure. Gamma radiation dose rate measurements were achieved by portable radiation monitoring equipment based on the energy range between 40 keV and 1.3 MeV. The measurements were performed on asphalt and soil surface level and also one meter above the ground surface. The gamma dose rate was also performed inside and outside of buildings over the district. The dose rates were found to be between 8.46μR/h and 34.66 μR/h. Indoor and outdoor effective dose rate of the gamma radiation exposure has been calculated to be 523μSv/y and 196μSv/y, respectively

  5. Operation of the radiation dose registration system for decontamination and related works

    International Nuclear Information System (INIS)

    Ogawa, Tsubasa; Yasutake, Tsuneo; Itoh, Atsuo; Miyabe, Kenjiro

    2017-01-01

    The radiation dose registration system for decontamination and related works was established on 15 November 2013. Radiation dose registration center and primary contractors of decontamination and related works manage decontamination registration and management system. As of 31 March 2017, 384 primary contractors joined in the radiation dose registration system for decontamination and related works. 383,087 quarterly exposure dose records for decontamination and related works were registered. Based on the registered data provided by the primary contractors, radiation dose registration center has released the statistical data that represent the radiation control status for workers engaged in radiation work at the work areas of decontamination and related works, etc. The statistical data shows that there were 40,377 workers engaged in decontamination and related works in 2015. The average exposure dose for workers was 0.6 mSv in 2015. The maximum exposure dose for workers was 7.8 mSv in 2015. Dose distribution by age of workers shows the range of 60 to 64 years old were most engaged in decontamination and related works in 2015. Dose distribution by gender of workers shows 97% of workers were male in 2015. From 2012 to 2015, about 95% of workers were exposed to radiation less than 3 mSv. And about 80% of workers were exposed to radiation less than 1 mSv. The average exposure dose per year was ranged from 0.5 to 0.7 mSv. (author)

  6. UV inactivation: Combined effects of UV radiation and xenobiotics in two strains of Saccharomyces

    International Nuclear Information System (INIS)

    Lochmann, E.R.; Lochmann, G.

    1997-01-01

    The effects of eight chemicals on the inactivation rate of ultraviolet radiation on the colony building capabilities of two strains of Saccharomyces cervisae - a wild type strain and a mutant deficient in excision repair - were studied. The insecticide methoxychlor, the herbicide 2,4-dichlorophenoxyacetic acid, the fungicide pentachlorophenol and its metabolite tetrachlorohydroquinone, as well as the chemicals acrylonitrile and 2,3-dichloro-1-propene have no significant impact on the effects of UV radiation in Saccharomyces cerevisae. Depending on the concentration, trichloroethylene increases the sensitivity to UV radiation. The herbicide paraquat provides efficient protection against UV radiation at concentrations where a toxic effect cannot be observed even without UV. The results were rather similar for both strains. (orig.) [de

  7. The Study of External Radiation Dose for Radiation Worker at PRSG-BATAN Serpong

    International Nuclear Information System (INIS)

    Sunarningsih; Mashudi; A Lilik W; Yosep S

    2012-01-01

    The study of External radiation dose for radiation worker at PRSG-BATAN Serpong has been carried out. The sample is taken from the System Reactor division (BSR), Operation Reactor division, (BOR) Safety division UPN, UJM and head of PRSG by setting Thermoluminescence Dosemeter (TLD) on the chest, then is detected by a tool TLD reader model 6600. The aim of this study is to evaluate the occupational exposure dose that has been accepted by the radiation worker for the last five years. The result in average doses at BSR is 0,99 mSv, BOR is 3,27 mSv, at BK is 0,69 mSv and UPN + UJM + head of PRSG is 0,03 mSv. The result highest doses at BSR is 6,58 mSv, BOR is 28,94 mSv, BK is 4,24 mSv, and UPN UJM Head of PRSG is 0,52 mSv. Dose interval radiation worker at PRSG BATAN ttd - 28,98 mSv. To overall the external personal dose acceptant for radiation worker at PRSG BATAN one below maximum permissible dose acceptant that allowed by BAPETEN, that is 20 mSv in average every year during five years. (author)

  8. 40K activities and potassium concentrations in tobacco samples of Mexican cigarettes

    International Nuclear Information System (INIS)

    Martinez, T.; Navarrete, M.; Cabrera, L.; Ramos, A.; Vazquez, K.; Juarez, F.

    2007-01-01

    Nine brands of tobacco cigarettes manufactured and distributed in the Mexican market were analyzed by γ-spectrometry to certify their nonartificial radioactive contamination. Since natural occurring radioactive materials (NORM) 40 K, 232 Th, 235 U, and 239 U (and decay products from the latter three nuclides) are the main sources for human radiation exposure, the aim of this work was to determine the activity of 40 K and potassium concentration. Averages of 40 K and potassium concentration were of 1.29 ± 0.18 Bq x g -1 , and 4.0 ± 0.57%. The annual dose equivalents to the whole body from ingestion and inhalation of 26 Bq 40 K were 0.23 μSv and 15.8 μSv, respectively. The corresponding 50 years committed dose equivalents was 0.23 μSv. The total committed dose to the lungs due to inhalation of 40 K in tobacco was 16 μSv. Potassium concentrations obtained in this work were in the same range of those obtained by INAA, so showing that the used technique is acute, reproducible, and accessible to laboratories equipped with low background scintillation detectors. (author)

  9. Implementation of ICRP-60 recommendations on dose limits to radiation workers in India

    International Nuclear Information System (INIS)

    Parthasarathy, K.S.

    2000-01-01

    The handling of radioactive material and radiation generating plants in India is regulated by the Atomic Energy Act, 1962 and rules issued under the Act. The Atomic Energy Regulatory Board enforces the rules. Currently, there are about 40,000 radiation workers in the country. Nearly half of them are employed in nuclear installations. During 1989, the Board considered the impact of restricting the maximum individual exposure to different values of dose limits. Through this analysis, the Board alerted all radiation users including persons responsible for radiation safety in nuclear facilities. When ICRP published ICRP-60, the Board issued directives to all radiation installations reducing the dose limit to occupational workers in a phased manner (40 mSv for 1991, 35 mSv for 1992 and 30 mSv for 1993). To meet the recommendations of ICRP-60, AERB issued a directive for the five year block 1994-1998, restricting the cumulative effective dose constraint to one hundred milliSievert (100 mSv) for individual radiation workers. Also, the annual effective dose to individual workers in any calendar year during the five-year block was restricted to thirty milliSievert (30 mSv). The stipulations of AERB are thus more conservative than those of ICRP. There was near total compliance with the dose limits by radiation installations in the country. For instance, in 1989, the number of radiation workers in nuclear power plants, who exceeded the dose level of 20 mSv/year was 9% of the total. This declined gradually to 2.2% in 1993 and 0.3% in 1997. During 1998, only 9 out of 10,145 exceeded 20 mSv/year. This has been achieved by the concerted efforts of the management, health physics staff and radiation workers. The health physicists regulated the radiation doses to workers by issuing work permits when the workers are assigned any job in high radiation areas. Appropriate training programmes are also in place. The broad guidelines to regulate radiation exposures in nuclear facilities

  10. Properties of Natural Radiation and Radioactivity

    International Nuclear Information System (INIS)

    Strom, Daniel J.

    2009-01-01

    Ubiquitous natural sources of radiation and radioactive material (naturally occurring radioactive material, NORM) have exposed humans throughout history. To these natural sources have been added technologically-enhanced naturally occurring radioactive material (TENORM) sources and human-made (anthropogenic) sources. This chapter describes the ubiquitous radiation sources that we call background, including primordial radionuclides such as 40K, 87Rb, the 232Th series, the 238U series, and the 235U series; cosmogenic radionuclides such as 3H and 14C; anthropogenic radionuclides such as 3H, 14C, 137Cs, 90Sr, and 129I; radiation from space; and radiation from technologically-enhanced concentrations of natural radionuclides, particularly the short-lived decay products of 222Rn ('radon') and 220Rn ('thoron') in indoor air. These sources produce radiation doses to people principally via external irradiation or internal irradiation following intakes by inhalation or ingestion. The effective doses from each are given, with a total of 3.11 mSv y-1 (311 mrem y-1) to the average US resident. Over 2.5 million US residents receive over 20 mSv y-1 (2 rem y-1), primarily due to indoor radon. Exposure to radiation from NORM and TENORM produces the largest fraction of ubiquitous background exposure to US residents, on the order of 2.78 mSv (278 mrem) or about 89%. This is roughly 45% of the average annual effective dose to a US resident of 6.2 mSv y-1 (620 mrem y-1) that includes medical (48%), consumer products and air travel (2%), and occupational and industrial (0.1%). Much of this chapter is based on National Council on Radiation Protection and Measurements (NCRP) Report No. 160, 'Ionizing Radiation Exposure of the Population of the United States,' for which the author chaired the subcommittee that wrote Chapter 3 on 'Ubiquitous Background Radiation.'

  11. Rape seed glucosinolate: radiation inactivation and physiological performance of broiler fed irradiated rapeseed meal

    International Nuclear Information System (INIS)

    Farag, M.Diaa El-Din H.

    1994-01-01

    Rape seeds meal (RSM) is a high quality protein supplement suitable for all classes of livestock. The major area of concern in animal nutrition has been glucosinolates and their derivative products which cause depressed performance in poultry or may be even toxic. Therefore, these substances must be removed or inactivated before the meal can be used as potential protein source for food or feed. I the current study, RSM has been used to test whether gamma radiation processing can inactivate glucosinolates as a step towards detoxication. Samples were exposed to gamma rays of 10, 50, 100 and 250 kGy. Approximated analysis showed that RSM was not affected by irradiation processing up to 250 kGy. However, the crude fiber content decreased at the highest dose while at doses of 10, 50 100 and 250 kGy the available lysine decreased by 6.76%, 9.46%, 17.84% and 22.43%, respectively. Radiation processing at 250 kGy significantly inactivated glucosinolate by 85% from its initial value. In a 8-week chick-feeding study, raw and irradiated RSM were applied at 30%. The diets containing raw and irradiated (at 10, 50 and 100 kGy) RSM had somewhat low growth and thyroid, liver and kidney enlargement compared to the basal control group. No significant difference was observed between chicks fed on RSM irradiated at 250 kGy and those fed on basal diet. No significant differences were observed in the serum protein, albumin, GPT, uric acid, creatine and basal diet groups. Those kept on raw and irradiated at 10, 50 and 100 kGy RSM had higher GOT than those kept on irradiated at 250 kGy RSM and basal diet. Radiation treatment of RSM up to 250 kGy improved its nutritional quality by decreasing the glucosinolate and consequently maintained the chicks in a better health condition. (author)

  12. The radiation-induced inactivation of microorganisms in non-aqueous suspension: The effect of selective alcohols and paraffins on the radiation sensitivity of aerated Bacillus pumilus spores

    International Nuclear Information System (INIS)

    Jacobs, G.P.

    1981-01-01

    The effect of model compounds comprising alcohols and paraffins on the radiation sensitivity of B. pumilus spores has been studied with the aim of understanding the radiation-induced inactivation of microorganisms when suspended in non-aqueous medium. This study is a prerequisite to the undertaking of radiation sterilization of non-aqueous pharmaceuticals. Spores of B. pumilus E601 mounted on kaolin powder were suspended in the appropriate organic agent and gamma irradiated under oxic conditions. Spores suspended in paraffins displayed increased radiation response over that for aerated buffered suspensions. Values of inactivation constant ranged between 2 x and 5 x that for buffer. Less pronounced modification of response was obtained for the alcohols. The results reveal a marked tendency for response to increase with decreasing polarity of the supending fluid. The partial miscibility of the alcohols in water enabled the examining of the transition from the response characteristic of aerated buffered suspensions to those of the spores in pure organic liquids. (orig./MG) [de

  13. Exposure of the Bulgarian population from natural and manmade ionizing radiation sources in the mid 90-ies

    International Nuclear Information System (INIS)

    Vasilev, G.; Bajrakova, A.; Ingilizova, Kh.; Khristova, M.; Karadzhov, A.

    1997-01-01

    The main radiation sources the Bulgarian population is exposed to, e.g. natural radiation background and manmade exposure such as occupational, medical, nuclear power engineering and the like, are analyzed. The study covers the period 1991-1994 but it also contains a number of retrospective assessments concerning the last few decades. It is prepared with a special reference to the forthcoming report of the United Nations Scientific Committee on the effect of atomic radiation scheduled for publication in 1998/1999. The Bulgarian population exposure presented as average annual effective collective doses amounts to 20240 mSv/a from natural background, 6400 mSv/a from x-ray diagnostics, 400 mSv/a from nuclear medicine, 17 mSv/a from occupational exposure (uranium mining excluded) etc. Total exposure in excess to background irradiation is about 40% of the background one

  14. ER Operations Installation of Three FLUTe Soil-Vapor Monitoring Wells (MWL-SV03 MWL-SV04 and MWL-SV05) at the Mixed Waste Landfill.

    Energy Technology Data Exchange (ETDEWEB)

    Copland, John Robin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    This installation report describes the May through July 2014 drilling activities performed for the installation of three multi-port soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) at the Mixed Waste Landfill (MWL), which is located at Sandia National Laboratories, New Mexico (SNL/NM). SNL/NM is managed and operated by Sandia Corporation (Sandia), a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy (DOE)/National Nuclear Security Administration. The MWL is designated as Solid Waste Management Unit (SWMU) 76 and is located in Technical Area (TA) III (Figure 1-1). The locations of the three soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) are shown in Figure 1-2

  15. Study on Efficacy of Gamma Radiation on the Inactivation of Highly Pathogenic Avian Influenza Virus H5N1 (Thai isolate) in Chicken Meat and Chicken Feces

    International Nuclear Information System (INIS)

    Pinyochon, Wasana; Piadang, Nattayana; Mulika, Ladda; Parchariyanon, Sujira; Vitittheeranon, Arag; Damrongwatapokin, Sudarat

    2006-09-01

    A study on the efficacy of gamma radiation on the inactivation of a highly pathogenic avian influenza virus H5N1 subtype, Thai isolate was carried out. The virus was in the form frozen infected allantoic fluid frozen chicken meat and frozen chicken feces. The result indicated that 9 kilo grey of gamma radiation could completely inactivated 106.0 EID50/ml of AIV infected allantoic fluid and 22 kiel grey and 15 kilo grey of gamma radiation completely inactivate 106.0 EID50/10/ grams of chicken meat and 106.0 EID50/5 grams of chicken feces respectively.

  16. Occupational radiation exposure in Germany in 2011. Report of the radiation protection register

    International Nuclear Information System (INIS)

    Frasch, Gerhard; Kammerer, Lothar; Karofsky, Ralf; Mordek, Else; Schlosser, Andrea; Spiesl, Josef

    2013-04-01

    In Germany, persons who are occupationally exposed to ionising radiation are monitored by several official dosimetry services that transmit the dose records about individual radiation monitoring to the Radiation Protection Register of the Federal Office for Radiation Protection (BfS). The purpose of the Radiation Protection Register is to supervise the keeping of the dose limits and to monitor the compliance with the radiation protection principle ''Optimisation'' by performing detailed annual statistical analyses of the monitored persons and their radiation exposure. The annual report of the Radiation Protection Register provides information about status and development of occupational radiation exposure in Germany. In 2011, about 350,000 workers were monitored with dosemeters for occupational radiation exposure. The number increased during the past five years continuously by 10 %. Only 19 % of the monitored persons received measurable personal doses. The average annual dose of these exposed workers was 0.58 mSv corresponding to 3 % of the annual dose limit of 20 mSv for radiation workers. In total, 7 persons exceeded the annual dose limit of 20 mSv, i.e. two cases per 100,000 monitored persons. The collective dose of the monitored persons decreased to 38.5 Person-Sv, the lowest value since the last fifty years of occupational dose monitoring. In 2010, 45 airlines calculated the route doses of 39,000 members of the aircraft crew personnel by using certified computer programmes for dose calculation and sent the accumulated monthly doses via the Federal Office for Civil Aviation (''Luftfahrt-Bundesamt, LBA'') to the BfS. The collective dose of the aircraft crew personnel is 83 person-Sv, and thus significantly higher than the total collective dose of the workers monitored with personal dosemeters (38.5 person-Sv). The annual average dose of aircraft crew personnel was 2.12 mSv and decreased compared to 2010 (2,30 mSv). In 2011, about 70,000 outside-workers were in

  17. Dissociation of DNA damage and mitochondrial injury caused by hydrogen peroxide in SV-40 transformed lung epithelial cells

    Directory of Open Access Journals (Sweden)

    Adcock Ian M

    2002-11-01

    Full Text Available Abstract Background Since lung epithelial cells are constantly being exposed to reactive oxygen intermediates (ROIs, the alveolar surface is a major site of oxidative stress, and each cell type may respond differently to oxidative stress. We compared the extent of oxidative DNA damage with that of mitochondrial injury in lung epithelial cells at the single cell level. Result DNA damage and mitochondrial injury were measured after oxidative stress in the SV-40 transformed lung epithelial cell line challenged with hydrogen peroxide (H2O2. Single cell analysis of DNA damage was determined by assessing the number of 8-oxo-2-deoxyguanosine (8-oxo-dG positive cells, a marker of DNA modification, and the length of a comet tail. Mitochondrial membrane potential, ΔΨm, was determined using JC-1. A 1 h pulse of H2O2 induced small amounts of apoptosis (3%. 8-oxo-dG-positive cells and the length of the comet tail increased within 1 h of exposure to H2O2. The number of cells with reduced ΔΨm increased after the addition of H2O2 in a concentration-dependent manner. In spite of a continual loss of ΔΨm, DNA fragmentation was reduced 2 h after exposure to H2O2. Conclusion The data suggest that SV-40 transformed lung epithelial cells are resistant to oxidative stress, showing that DNA damage can be dissociated from mitochondrial injury.

  18. Natural background radiation at flight altitudes; Natuerliche Strahlenexposition in Flughoehen durch kosmische Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Wissmann, F. [Physikalisch-Technische Bundesanstalt, Berlin (Germany). FB Ionenbeschleuniger und Referenzstrahlungsfelder

    2006-12-15

    At sea level, the background radiation of about 40 nSv/h consists of about 80 percent of muons and electrons and about 0 percent of neutrons. The picture is different at an altitude of 10 km. Here, the background dose equivalent of about 5000 nSv/h (= 5 {mu}Sv/h) consists of about 60 percent of neutrons and about 25 percent of muons and electrons. Protons account for about 15 percent. This particle composition makes dosimetric measurements difficult. In addition, the energy emitted by the particles is far beyond the the measuring range of conventional radiation protection dosemeters. For these reasons, conventional dosemeters are not suited for applications in aeroplanes and such. The PTB method for measuring local dose rates uses a proportional counter whose wall consists of a tissue equivalent material and which is operated with tissue equivalent counting gas at very low pressure (about 40 hPa). (orig.)

  19. The combined effect of heat and gamma irradiation on the inactivation of selected microorganisms associated with food hygiene

    International Nuclear Information System (INIS)

    Kwon, O.J.; Byun, M.W.

    1996-01-01

    The bactericidal effectiveness of radiation alone or in combination with heat against 8 strains associated with food hygiene were evaluated. In the case of radiation alone, D values of micro-organisms were 0.14~0.48 kGy, and inactivation factors were 4.54~21.43 at the doses of 2~3 kGy. Escherichia coli was the most sensitive among the tested strains, resulting in a D value of 0.14 kGy. D values of tile strains were 10~40 minutes at 50±1°C and 5~10 minutes at 60±1°C. Combination with heat and radiation showed D values of 0.04~0.31. Inactivation factors were 6.45~75 at the doses of 2 to 3 kGy. Therefore, heat treatment prior to irradiation significantly increased activation rate by increasing radiation sensitivity of microorganisms

  20. Solar Radiation Disinfection of Drinking Water at Temperate Latitudes: Inactivation rates for an optimized reactor configuration

    Science.gov (United States)

    Solar radiation-driven inactivation of bacteria, virus and protozoan pathogen models was quantified in simulated drinking water at a temperate latitude (34°S). The water was seeded with Enterococcus faecalis, Clostridium sporogenes spores, and P22 bacteriophage, each at ca 1 x 10...

  1. Inactivation of Lassa, Marburg, and Ebola viruses by gamma irradiation

    International Nuclear Information System (INIS)

    Elliott, L.H.; McCormick, J.B.; Johnson, K.M.

    1982-01-01

    Because of the cumbersome conditions experienced in a maximum containment laboratory, methods for inactivating highly pathogenic viruses were investigated. The infectivity of Lassa, Marburg, and Ebola viruses was inactivated without altering the immunological activity after radiation with 60 CO gamma rays. At 4 degrees C, Lassa virus was the most difficult to inactivate with a rate of 5.3 X 10(-6) log 50% tissue culture infective dose per rad of 60 CO radiation, as compared with 6.8 X 10(-6) log 50% tissue culture infective dose per rad for Ebola virus and 8.4 X 10(-6) log 50% tissue culture infective dose per rad for Marburg virus. Experimental inactivation curves, as well as curves giving the total radiation needed to inactivate a given concentration of any of the three viruses, are presented. The authors found this method of inactivation to be superior to UV light or beta-propiolactone inactivation and now routinely use it for preparation of material for protein-chemistry studies or for preparation of immunological reagents

  2. Inactivation of Lassa, Marburg, and Ebola viruses by gamma irradiation

    International Nuclear Information System (INIS)

    Elliott, L.H.; McCormick, J.B.; Johnson, K.M.

    1982-01-01

    Because of the cumbersome conditions experienced in a maximum containment laboratory, methods for inactivating highly pathogenic viruses were investigated. The infectivity of Lassa, Marburg, and Ebola viruses was inactivated without altering the immunological activity after radiation with 60 Co gamma rays. At 4 degrees C, Lassa virus was the most difficult to inactivate with a rate of 5.3 X 10(-6) log 50% tissue culture infective dose per rad of 60 Co radiation, as compared with 6.8 X 10(-6) log 50% tissue culture infective dose per rad for Ebola virus and 8.4 X 10(-6) log 50% tissue culture infective dose per rad for Marburg virus. Experimental inactivation curves, as well as curves giving the total radiation needed to inactivate a given concentration of any of the three viruses, are presented. We found this method of inactivation to be superior to UV light or beta-propiolactone inactivation and now routinely use it for preparation of material for protein-chemistry studies or for preparation of immunological reagents

  3. Size determination of an equilibrium enzymic system by radiation inactivation

    International Nuclear Information System (INIS)

    Simon, P.; Swillens, S.; Dumont, J.E.

    1982-01-01

    Radiation inactivation of complex enzymic systems is currently used to determine the enzyme size and the molecular organization of the components in the system. An equilibrium model was simulated describing the regulation of enzyme activity by association of the enzyme with a regulatory unit. It is assumed that, after irradiation, the system equilibrates before the enzyme activity is assayed. The theoretical results show that the target-size analysis of these numerical data leads to a bad estimate of the enzyme size. Moreover, some implicit assumptions such as the transfer of radiation energy between non-covalently bound molecules should be verified before interpretation of target-size analysis. It is demonstrated that the apparent target size depends on the parameters of the system, namely the size and the concentration of the components, the equilibrium constant, the relative activities of free enzyme and enzymic complex, the existence of energy transfer, and the distribution of the components between free and bound forms during the irradiation. (author)

  4. Radiation inactivation studies of renal brush border water and urea transport

    International Nuclear Information System (INIS)

    Verkman, A.S.; Dix, J.A.; Seifter, J.L.; Skorecki, K.L.; Jung, C.Y.; Ausiello, D.A.

    1985-01-01

    Radiation inactivation was used to determine the nature and molecular weight of water and urea transport pathways in brush border membrane vesicles (BBMV) isolated from rabbit renal cortex. BBMV were frozen to -50 degrees C, irradiated with 1.5 MeV electrons, thawed, and assayed for transport or enzyme activity. The freezing process had no effect on enzyme or transport kinetics. BBMV alkaline phosphatase activity gave linear ln(activity) vs. radiation dose plots with a target size of 68 +/- 3 kDa, similar to previously reported values. Water and solute transport were measured using the stopped-flow light-scattering technique. The rates of acetamide and osmotic water transport did not depend on radiation dose (0-7 Mrad), suggesting that transport of these substances does not require a protein carrier. In contrast, urea and thiourea transport gave linear ln(activity) vs. dose curves with a target size of 125-150 kDa; 400 mM urea inhibited thiourea flux by -50% at 0 and 4.7 Mrad, showing that radiation does not affect inhibitor binding to surviving transporters. These studies suggest that BBMV urea transport requires a membrane protein, whereas osmotic water transport does not

  5. Evaluation of radiation protection in some nuclear medicine department

    International Nuclear Information System (INIS)

    Abdelrahim, Yassir Mohammed

    2015-12-01

    This study was carryout to evaluate the radiation protection in nuclear medicine department in Sudan, accordance with the standards international recommendation and code of practice for radiation protection in nuclear medicine, the evaluation was done for three nuclear medicine departments, included direct measurement of dose rate and the contamination level in some areas, were radiation sources, radiation workers and public are involved. The data was collected and analyzed from the results for three nuclear medicine departments that the average reading of ambient dose rate in : outside the door of imaging room (SPECT) 0.18μSv/h in hospital (1)& and 0.19μSv/h in hospital(2) and 0.19μSv/h hospital(3), inside control of imaging room (SPECT) 27.8μSv/h in hospital(1)& 0.14μSv/h in hospital(2)& 14μSv/h in hospital(3), inside the injection room 28.81μSv/h in hospital(1), 0.36μSv/h in hpspital(2), 0.06μSv/h in hospital(3) outside the door of lap, 0.65μSv/h in hospital(1), 0.13μSv/h in hospital(2) & 0.12μSv/h in hospital(3), inside the hot lap, 9.68μSv/h in hospital(1) & 0.30μSv/h in hospital(2) & 0.85 μSv/h in hospital(3), in outsidee the door of waiting room of injected patient 1.41μSv/h in hospital(1)& 0.16μSv/h in hospital(2) & 1.08μSv/h in hospital(3). Avaerge reading of contamination in: Floor of hot lap 44.50 B/cm"2 hospital(1) & 4.42B/cm"2in hospital(2) & 6.22 B/cm"2 in hospital (3) . on the bench tap 186.30 B/cm"2 hospital(1), 19.91 B/cm"2 in hospital(2) & 8.77B/cm"2 in hospital(3) floor of injection room 12.60 B/cm"2 in hospital(1) & 11.70 B/cm"2 in hospital(2) & 13.73 B/cm"2 hospital(3) & table of injection room 13.00 B/cm"2 in hospital(1)& 11.70 B/cm"2in hospital(2)& 13.73 B/cm"2 in hospital & tble of injection room 13.00 B/cm"2 in hospital(1) & 20.40 B/cm"2 in hospital(2) & 23.23 B/cm"2 B/cm"2 in hospital(3) on the shield of working surface 144.30 B/cm in hospital(1)& 47.00 B/cm"2 in hospital(2) & 52.33 B/cm"2 in hospital(3) , and makes check

  6. Oxygen-independent inactivation of Haemophilus influenzae transforming DNA by monochromatic radiation: action spectrum, effect of histidine and repair

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera-Juarez, E; Setlow, J K; Swenson, P A; Peak, M J

    1976-01-01

    The action spectrum for the oxygen-independent inactivation of native transforming DNA from Haemophilus influenzae with near-uv radiation revealed a shoulder beginning at 334 and extending to 460 nm. The presence of 0.2 M histidine during irradiation produced a small increase in inactivation at 254, 290 and 313 nm, a large increase at 334 nm and a decrease in inactivation at 365, 405, and 460 nm. Photoreactivation did not reverse the DNA damage produced at pH 7.0 at 334, 365, 405 and 460 nm, but did reactivate the DNA after irradiation at 254, 290 and 313 nm. The inactivation of DNA irradiated at 254, 290 and 313 nm was considerably greater when the transforming ability was assayed in an excision-defective mutant compared with the wild type, although DNA irradiated at 334, 365, 405 and 460 nm showed smaller differences. These results suggest that the oxygen-independent inactivation of H. influenzae DNA at pH 7 by irradiation at 334, 365, 405 and 460 nm is caused by lesions other than pyrimidine dimers.

  7. Radiation doses to patients undergoing barium meal and barium enema examinations

    International Nuclear Information System (INIS)

    Delichas, M. G.; Hatziioannou, K.; Papanastassiou, E.; Albanopoulou, P.; Chatzi, E.; Sioundas, A.; Psarrakos, K.

    2004-01-01

    The radiation doses received by patients during 41 barium meal (BM) and 42 barium enema (BE) examinations in two Greek hospitals are presented. Radiation dose was measured in terms of the dose area product (DAP). The effective dose and doses to certain organs were estimated using the ODS-60 software. Mean total DAP values were found to be 25 ± 11 Gy cm 2 for BM and 60 ± 35 Gy cm 2 for BE examinations, whereas the estimated mean values of effective dose were 8.6 ± 4.0 and 24 ± 16 mSv respectively. DAP to effective dose conversion coefficients were estimated to be 0.34 mSv per Gy cm 2 for BM and 0.41 mSv per Gy cm 2 for BE. (authors)

  8. The estimation of doses to the inhabitants arising from natural radiation source in the high background radiation area of Yangjiang, China

    International Nuclear Information System (INIS)

    Yuan Yongling; Shen Hong; Morishima, H.; Wei Lvxin; Jian Yuannu

    2004-01-01

    Objective: The purposes is to estimate the average annual effective dose of the inhabitants and absorbed dose in some human tissues and organs arising from natural radiation sources in the High Background Radiation Area (HBRA) of Yangjiang and in the neighboring Control Area (CA). In order to provide more effective evidence for analyzing the dose-effect relationships among the cohort members in the investigated areas, authors divided the local inhabitant into different dose-groups. Methods: The authors measured the environmental gamma external radiation levels and individual accumulated doses of 5293 people in the investigated areas. The concentrations for 222 Rn, 220 Rn and their decay products in air were also surveyed. The authors estimated the internal doses of natural radionuclides based on the results obtained from measurements in food, in drinking water, in human teeth, in several human tissues, in human placenta, and in activity concentration of exhaled 222 Rn and 220 Rn of the residents living in the investigated areas. Results: The estimation of average annual effective doses in HBRA and CA based on the data of environmental measurements of radiation level respectively are 2.12 ± 0.29 mSv a -1 and 0.69 ± 0.09 mSv a -1 . The sources of higher background radiation in HBRA are mainly contributed from terrestrial gamma radiation. The estimation of average annual effective doses to the residents arising from inhalation of 222 Rn, 220 Rn and their decay products was 3.28 mSv a -1 in HBRA, while that in CA was 1.03 mSv a -1 . The values of the absorbed dose of the residents in their trachea-bronchial tree and lung in HBRA arising from inhalation of 222 Rn, 220 Rn and their decay products are 5.40 mGy a -1 and 1.08 mGy a -1 respectively, which are about four times of the values of the absorbed dose in CA. The estimation of average annual effective doses to the inhabitants caused by 226 Ra and 228 Ra in HBRA and CA were 281.88 μSv a -1 and 84.54 μSv a -1

  9. Radiation biology for pediatric radiologists

    International Nuclear Information System (INIS)

    Hall, Eric J.

    2009-01-01

    The biological effects of radiation result primarily from damage to DNA. There are three effects of concern to the radiologist that determine the need for radiation protection and the dose principle of ALARA (As Low As Reasonably Achievable). (1) Heritable effects. These were thought to be most important in the 1950s, but concern has declined in recent years. The current ICRP risk estimate is very small at 0.2%/Sv. (2) Effects on the developing embryo and fetus include weight retardation, congenital anomalies, microcephaly and mental retardation. During the sensitive period of 8 to 15 weeks of gestation, the risk estimate for mental retardation is very high at 40%/Sv, but because it is a deterministic effect, there is likely to be a threshold of about 200 mSv. (3) Carcinogenesis is considered to be the most important consequence of low doses of radiation, with a risk of fatal cancer of about 5%/Sv, and is therefore of most concern in radiology. Our knowledge of radiation carcinogenesis comes principally from the 60-year study of the A-bomb survivors. The use of radiation for diagnostic purposes has increased dramatically in recent years. The annual collective population dose has increased by 750% since 1980 to 930,000 person Sv. One of the principal reasons is the burgeoning use of CT scans. In 2006, more than 60 million CT scans were performed in the U.S., with about 6 million of them in children. As a rule of thumb, an abdominal CT scan in a 1-year-old child results in a life-time mortality risk of about one in a thousand. While the risk to the individual is small and acceptable when the scan is clinically justified, even a small risk when multiplied by an increasingly large number is likely to produce a significant public health concern. It is for this reason that every effort should be made to reduce the doses associated with procedures such as CT scans, particularly in children, in the spirit of ALARA. (orig.)

  10. DNA double strand breaks as the critical type of damage with regard to inactivation of cells through ionizing radiation

    International Nuclear Information System (INIS)

    Frankenberg, D.

    1985-01-01

    This report presents the results of an investigation into the effects of ionizing radiation on eukaryotic cells, aimed at revealing the molecular mechanisms leading to cell inactivation as a result of ionizing radiation. The quantitative determination of radiation-induced double strand breaks (DSB) is done via sedimentation of the DNA released from the cells in a neutral saccharose gradient in a preparative ultracentrifuge. The 'experimental mass spectrum' of DNA molecules thus obtained, the mean number of DSB per cell is calculated using a special computer program which simulates the stochastic induction of DSB in the DNA of non-irradiated cells and links the 'simulated' mass spectrum with the 'experimental' one on the basis of the least square fit. The experimental and theoretical studies with the eukaryote yeast on the whole allow insight into the relation between energy absorption and the inactivation of irradiated cells. (orig./MG) [de

  11. Molecular sizes of lichen ice nucleation sites determined by gamma radiation inactivation analysis

    International Nuclear Information System (INIS)

    Kieft, T.L.; Ruscetti, T.

    1992-01-01

    It has previously been shown that some species of lichen fungi contain proteinaceous ice nuclei which are active at temperatures as warm as −2 °C. This experiment was undertaken to determine the molecular sizes of ice nuclei in the lichen fungus Rhizoplaca chrysoleuca and to compare them to bacterial ice nuclei from Pseudomonas syringae. Gamma radiation inactivation analysis was used to determine molecular weights. Radiation inactivation analysis is based on target theory, which states that the likelihood of a molecule being inactivated by gamma rays increases as its size increases. Three different sources of ice nuclei from the lichen R. chrysoleuca were tested: field-collected lichens, extract of lichen fungus, and a pure culture of the fungus R. chrysoleuca. P. syringae strain Cit7 was used as a source of bacterial ice nuclei. Samples were lyophilized, irradiated with gamma doses ranging from 0 to 10.4 Mrads, and then tested for ice nucleation activity using a droplet-freezing assay. Data for all four types of samples were in rough agreement; sizes of nucleation sites increased logarithmically with increasing temperatures of ice nucleation activity. Molecular weights of nucleation sites active between −3 and −4 °C from the bacteria and from the field-collected lichens were approximately 1.0 × 10 6 Da. Nuclei from the lichen fungus and in the lichen extract appeared to be slightly smaller but followed the same log-normal pattern with temperature of ice nucleation activity. The data for both the bacterial and lichen ice nuclei are in agreement with ice nucleation theory which states that the size of ice nucleation sites increases logarithmically as the temperature of nucleation increases linearly. This suggests that although some differences exist between bacterial and lichen ice nucleation sites, their molecular sizes are quite similar

  12. Some cosmic radiation dose measurements aboard flights connecting Zagreb Airport

    International Nuclear Information System (INIS)

    Vukovic, B.; Radolic, V.; Lisjak, I.; Vekic, B.; Poje, M.; Planinic, J.

    2008-01-01

    When primary particles from space, mainly protons, enter the atmosphere, they produce interactions with air nuclei, and cosmic-ray showers are induced. The radiation field at aircraft altitude is complex, with different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard A320 and ATR40 aircraft was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter; the neutron dose was measured with the neutron dosimeter consisted of LR-115 track detector and boron foil BN-1 or 10 B converter. The estimated occupational effective dose for the aircraft crew (A320) working 500 h per year was 1.64 mSv. Another experiment was performed at the flights Zagreb-Paris-Buenos Aires and reversely, when one measured non-neutron cosmic radiation dose; for 26.7 h of flight, the MINI 6100 dosimeter gave an average dose rate of 2.3 μSv/h and the TLD dosimeter registered the dose equivalent of 75 μSv or the average dose rate of 2.7 μSv/h; the neutron dosimeter gave the dose rate of 2.4 μSv/h. In the same month, February 2005, a traveling to Japan (24-h-flight: Zagreb-Frankfurt-Tokyo and reversely) and the TLD-100 measurement showed the average dose rate of 2.4 μSv/h; the neutron dosimeter gave the dose rate of 2.5 μSv/h. Comparing dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level, we could conclude that the neutron component carried about 50% of the total dose, that was near other known data

  13. Some cosmic radiation dose measurements aboard flights connecting Zagreb Airport

    Energy Technology Data Exchange (ETDEWEB)

    Vukovic, B.; Radolic, V. [Department of Physics, University of Osijek, Osijek, P.O. Box 125 (Croatia); Lisjak, I. [Croatia Airlines, Zagreb (Croatia); Vekic, B. [Rudjer Boskovic Institute, Zagreb (Croatia); Poje, M. [Department of Physics, University of Osijek, Osijek, P.O. Box 125 (Croatia); Planinic, J. [Department of Physics, University of Osijek, Osijek, P.O. Box 125 (Croatia)], E-mail: planinic@ffos.hr

    2008-02-15

    When primary particles from space, mainly protons, enter the atmosphere, they produce interactions with air nuclei, and cosmic-ray showers are induced. The radiation field at aircraft altitude is complex, with different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard A320 and ATR40 aircraft was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter; the neutron dose was measured with the neutron dosimeter consisted of LR-115 track detector and boron foil BN-1 or {sup 10}B converter. The estimated occupational effective dose for the aircraft crew (A320) working 500 h per year was 1.64 mSv. Another experiment was performed at the flights Zagreb-Paris-Buenos Aires and reversely, when one measured non-neutron cosmic radiation dose; for 26.7 h of flight, the MINI 6100 dosimeter gave an average dose rate of 2.3 {mu}Sv/h and the TLD dosimeter registered the dose equivalent of 75 {mu}Sv or the average dose rate of 2.7 {mu}Sv/h; the neutron dosimeter gave the dose rate of 2.4 {mu}Sv/h. In the same month, February 2005, a traveling to Japan (24-h-flight: Zagreb-Frankfurt-Tokyo and reversely) and the TLD-100 measurement showed the average dose rate of 2.4 {mu}Sv/h; the neutron dosimeter gave the dose rate of 2.5 {mu}Sv/h. Comparing dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level, we could conclude that the neutron component carried about 50% of the total dose, that was near other known data.

  14. A high-performance doped photocatalysts for inactivation of total coliforms in superficial waters using different sources of radiation.

    Science.gov (United States)

    Claro, Elis Marina Turini; Bidoia, Ederio Dino; de Moraes, Peterson Bueno

    2016-07-15

    Photocatalytic water treatment has a currently elevated electricity demand and maintenance costs, but the photocatalytic water treatment may also assist in overcoming the limitations and drawbacks of conventional water treatment processes. Among the Advanced Oxidation Processes, heterogeneous photocatalysis is one of the most widely and efficiently used processes to degrade and/or remove a wide range of polluting compounds. The goal of this work was to find out a highly efficient photocatalytic disinfection process in superficial water with different doped photocatalysts and using three sources of radiation: mercury vapor lamp, solar simulator and UV-A LED. Three doped photocatalysts were prepared, SiZnO, NSiZnO and FNSiZnO. The inactivation efficiency of each synthesized photocatalysts was compared to a TiO2 P25 (Degussa(®)) 0.5 g L(-1) control. Photolysis inactivation efficiency was 85% with UV-A LED, which is considered very high, demanding low electricity consumption in the process, whereas mercury vapor lamp and solar simulator yielded 19% and 13% inactivation efficiency, respectively. The best conditions were found with photocatalysts SiZnO, FNSiZnO and NSiZnO irradiated with UV-A LED, where efficiency exceeded 95% that matched inactivation of coliforms using the same irradiation and photocatalyst TiO2. All photocatalysts showed photocatalytic activity with all three radiation sources able to inactivate total coliforms from river water. The use of UV-A LED as the light source without photocatalyst is very promising, allowing the creation of cost-effective and highly efficient water treatment plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Estimation by radiation inactivation of the size of functional units governing Sendai and influenza virus fusion

    International Nuclear Information System (INIS)

    Bundo-Morita, K.; Gibson, S.; Lenard, J.

    1987-01-01

    The target sizes associated with fusion and hemolysis carried out by Sendai virus envelope glycoproteins were determined by radiation inactivation analysis. The target size for influenza virus mediated fusion with erythrocyte ghosts at pH 5.0 was also determined for comparison. Sendai-mediated fusion with erythrocyte ghosts at pH 7.0 was likewise inactivated exponentially with increasing radiation dose, yielding a target size of 60 +/- 6 kDa, a value consistent with the molecular weight of a single F-protein molecule. The inactivation curve for Sendai-mediated fusion with cardiolipin liposomes at pH 7.0, however, was more complex. Assuming a multiple target-single hit model, the target consisted of 2-3 units of ca. 60 kDa each. A similar target was seen if the liposome contained 10% gangliosides or if the reaction was measured at pH 5.0, suggesting that fusion occurred by the same mechanism at high and low pH. A target size of 261 +/- 48 kDa was found for Sendai-induced hemolysis, in contrast with influenza, which had a more complex target size for this activity. Sendai virus fusion thus occurs by different mechanisms depending upon the nature of the target membrane, since it is mediated by different functional units. Hemolysis is mediated by a functional unit different from that associated with erythrocyte ghost fusion or with cardiolipin liposome fusion

  16. Natural background radiation exposures world-wide

    International Nuclear Information System (INIS)

    Bennett, B.G.

    1993-01-01

    The average radiation dose to the world's population from natural radiation sources has been assessed by UNSCEAR to be 2.4 mSv per year. The components of this exposure, methods of evaluation and, in particular, the variations in the natural background levels are presented in this paper. Exposures to cosmic radiation range from 0.26 mSv per year at sea level to 20 times more at an altitude of 6000 m. Exposures to cosmogenic radionuclides ( 3 H, 14 C) are relatively insignificant and little variable. The terrestrial radionuclides 40 K, 238 U, and 232 Th and the decay products of the latter two constitute the remainder of the natural radiation exposure. Wide variations in exposure occur for these components, particularly for radon and its decay products, which can accumulate to relatively high levels indoors. Unusually high exposures to uranium and thorium series radionuclides characterize the high natural background areas which occur in several localized regions in the world. Extreme values in natural radiation exposures have been estimated to range up to 100 times the average values. (author). 15 refs, 3 tabs

  17. Risk assessment and late effects of radiation in low-earth orbits

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1989-01-01

    The radiation dose rates in low-earth orbits are dependent on the altitude and orbital inclination. The doses to which the crews of space vehicles are exposed is governed by the duration of the mission and the shielding, and in low-earth orbit missions protons are the dominant particles encountered. The risk of concern with the low dose rates and the relatively low total doses of radiation that will be incurred on the space station is excess cancer. The National Council on Radiation Protection and Measurements has recently recommended career dose-equivalent limits that take into account sex and age. The new recommendations for career limits range from 1.0 Sv to 4 Sv, depending on sex and on the age at the time of their first space mission, compared to a single career limit of 4.0 Sv previously used by NASA. Risk estimates for radiated-induced cancer are evolving and changes in the current guidance may be required in the next few years. 10 refs., 1 fig., 3 tabs

  18. Is the standard dose rate for de-contamination, 0.23 mc-Sv/hr, truly 1 mSv/year?

    International Nuclear Information System (INIS)

    Furuta, Sadaaki

    2014-01-01

    Examined is the validity of the standard dose rates in the title, which have been additionally defined by Ministry of the Environment (ME) to the measures of Fukushima Nuclear Power Plant Accident. The standard 0.23 mc-Sv/hr is the sum of natural ambient dose rate 0.04 mc-Sv/hr in average of Japan as measured with NaI scintillation surveymeter, plus additional accidental exposure dose 1 mSv/y, which is defined equivalent to 0.19 mc-Sv/hr. Here, the equation of addition 0.04+0.19 mc-Sv/hr is not exactly correct because the unit of each dose value has different means as follows. The natural dose is derived from the value 5.8 mc-R/hr (0.038 mc-Sv/hr, effective dose) of the average national natural dose data (2011) of Ministry of Education, Culture, Sports, Science and Technology. However, if the measurement is done with the surveymeter which practically gives 1 cm dose equivalent, the rate is calculated to be 0.06 mc-Sv/hr. When the Fukushima prefectural natural dose rate 6.4 mc-R/hr is employed, the calculation gives 0.07 mc-Sv/hr. ME defines the additional doses to be 0.19 mc-Sv/hr and 1 mSv/y, which are derived from the calculation: (0.19 mc-Sv/hr x 8 hr outdoor + 0.19 mc-Sv/hr x 0.4 indoor, shielded) x 365 d/y= 1 mSv/y. The dose is assumed to be measurable with the surveymeter (1 cm dose equivalent) and thereby calculation, if the source is mainly "1"3"4Cs and "1"3"7Cs, gives the effective dose of 0.32 mc-Sv/hr to be managed by the meter. As this, the effective dose unit and 1 cm equivalent dose unit are used for calculation of the administrative standard dose rate of 1 mSv/y, which should be recognized by both radiological experts and administration for the explanation to general public. (T.T.)

  19. Cryo-electron microscopy of vitrified SV40 minichromosomes: the liquid drop model.

    Science.gov (United States)

    Dubochet, J; Adrian, M; Schultz, P; Oudet, P

    1986-03-01

    The structure of SV40 minichromosomes has been studied by cryo-electron microscopy of vitrified thin layers of solution. In high-salt buffer (130 mM NaCl), freshly prepared minichromosomes are condensed into globules 30 nm or more in diameter. On the micrograph, they appear to be formed by the close packing of 10 nm granules which give rise to a 10 nm reflection in the optical diffractogram. The globules can adopt many different conformations. At high concentration, they fuse into a homogeneous 'sea' of closely packed 10 nm granules. In low-salt buffer (less than 10 mM NaCl), the globules open, first into 10 nm filaments, and then into nucleosome-strings. The 'liquid drop' model is proposed to explain the condensed structure of the minichromosome in high-salt buffer: nucleosomes stack specifically on top of one another, thus forming the 10 nm filaments. 10 nm filaments in turn, tend to aggregate laterally. Optimizing both these interactions results in the condensation of 10 nm filaments or portions thereof into a structure similar to that of a liquid. Some implications of this model for the structure of cellular chromatin are discussed.

  20. Assessment of natural background radiation in one of the highest regions of Ecuador

    Science.gov (United States)

    Pérez, Mario; Chávez, Estefanía; Echeverría, Magdy; Córdova, Rafael; Recalde, Celso

    2018-05-01

    Natural background radiation was measured in the province of Chimborazo (Ecuador) with the following reference coordinates 1°40'00''S 78°39'00''W, where the furthest point to the center of the planet is located. Natural background radiation measurements were performed at 130 randomly selected sites using a Geiger Müller GCA-07W portable detector; these measurements were run at 6 m away from buildings or walls and 1 m above the ground. The global average natural background radiation established by UNSCEAR is 2.4 mSv y-1. In the study area measurements ranged from 0.57 mSv y-1 to 3.09 mSv y-1 with a mean value of 1.57 mSv y-1, the maximum value was recorded in the north of the study area at 5073 metres above sea level (m.a.s.l.), and the minimum value was recorded in the southwestern area at 297 m.a.s.l. An isodose map was plotted to represent the equivalent dose rate due to natural background radiation. An analysis of variance (ANOVA) between the data of the high and low regions of the study area showed a significant difference (p < α), in addition a linear correlation coefficient of 0.92 was obtained, supporting the hypothesis that in high altitude zones extraterrestrial radiation contributes significantly to natural background radiation.

  1. Radiation-induced cataract

    International Nuclear Information System (INIS)

    Martignoni, K.

    1986-01-01

    Dose assessments for cataract threshold doses are available based on epidemiological studies of radiotherapy patients, survivors of the nuclear bombing of Hiroshima and Nagasaki, and of persons with occupational exposure to radiation. According to these, short-term application of low-level LET radiation of a dose ranging between 0.5 and 2.0 Gy may suffice to cause a cataract in the course of a few months or years which results in inpairment of vision (UNSCEAR, 1982). In fractionated irradiation, cataractogenic threshold dose increases to 4 Sv at treatment times between 3 weeks and 3 months, and to more than 5 Sv at more than 3 months (ICRP 41). Densely ionizing radiation must be assumed to have threshold doses between 2 and 20 Sv. An ICRP assessment (ICRP Publ. No. 41, 1984) gives a threshold dose of more than 8 Sv for a vision-impairing cataract if these was protracted irradiation at a low-level dose rate. Concerning radiation protection, a maximum lens dose of 150 mSv per annum was recommended which should not be exceeded. This indicates a maximum of 7.5 Sv of exposure throughout a period of 50 years of working life. (orig./HP) [de

  2. A review of cancer mortality data of radiation workers of Nuclear Power Plant, Paks, Hungary, in the light the international radiation epidemiology study

    International Nuclear Information System (INIS)

    Turai, I.; Kerekes, A.; Otos, M.; Veress, K.

    2007-01-01

    Complete text of publication follows. Objective: To give a review of cancer mortality data among Hungarian radiation workers in nuclear industry in comparison with the results of the international nuclear workers' study prevailing the size of the study group of all former studies. Methods: Retrospective cohort study including 598,068 workers of 154 nuclear establishments in 15 countries (AUS, BEL, CAN, FIN, FRA, GER, HUN, JAP, LIT, ROK, SLK, SPA, SWE, UK, USA) coordinated by the International Agency for Research on Cancer (IARC, Lyon, France). The national study was extended for an additional 4-year period. Results: In the international study 407,391 persons in 13 years of average employment received 19.4 mSv mean cumulative dose, while in the national study 3322 radiation workers of Nuclear Power Plant (NPP) Paks, Hungary, in 14 years of follow-up period accumulated in average 5.13 mSv, only. There were 5233 cancer deaths registered in the international study, associated with an estimated ERR of 0.97 per Sv. Thus, 19.4 mSv recorded cumulative dose can explain 1 to 2% of cancer death cases. In radiation workers of NPP, Paks, during the period of 1985-1998 there were 40 cancer deaths observed against the expected 58.8 cases. In a further four year period (1999-2002) 29 cancer death cases were identified vs. the expected 65.5 cases. The SMR for the cancer death cases registered in recent and former radiation workers of NPP, Paks in the 18-year follow-up period is 56%. The SMR from all causes was even lower, 40% only. Conclusions: In the international study the mean accumulated radiation dose received by nuclear workers in 13 years is below of the recent annual dose limit (20 mSv/yr of the effective dose). The average value for the whole of radiation workers in 15 countries is almost 4-times higher of that registered in Hungary. The 'healthy worker effect' in the nuclear industry, and particularly in Hungary has been proven, once again. Nevertheless, the results

  3. Estimation of radiation dose received by the radiation workers during radiographic testing

    International Nuclear Information System (INIS)

    Mohammed, N. A. H. O.

    2013-08-01

    This study was conducted primarily to evaluate occupational radiation dose in industrial radiography during radiographic testing at Balil-Hadida, with the aim of building up baseline data on radiation exposure in the industrial radiography practice in Sudan. Dose measurements during radiographic testing were performed and compared with IAEA reference dose. In this research the doses measured by using hand held radiation survey meter and personal monitoring dosimeter. The results showed that radiation doses ranged between minimum (0.448 mSv/ 3 month) , and maximum (1.838 mSv / 3 month), with an average value (0.778 mSv/ 3 month), and the standard deviation 0.292 for the workers used gamma mat camera. The analysis of data showed that the radiation dose for all radiation worker are receives less than annual limit for exposed workers 20 mSv/ year and compare with other study found that the dose received while body doses ranging from 0.1 to 9.4 mSv/ year, work area design in all the radiography site followed the three standard rules namely putting radiation signs, reducing access to control area and making of boundaries. Thus the accidents arising from design faults not likely to occur at these site. Results suggest that adequate fundamental training of radiation workers in general radiography prior to industrial radiography work will further improve the standard of personnel radiation protection. (Author)

  4. Production of DNA strand breaks by ionizing radiation of different quality and their consequences for cell inactivation

    International Nuclear Information System (INIS)

    Kampf, G.

    1983-07-01

    The production of single- and double-strand breaks (DSB) in the DNA of Chinese hamster cells (V 79) was studied by use of 11 radiation qualities, with some also under hypoxic conditions. The aim was to find relations between the induction of lesions on the molecular level and the expression of this damage on the cellular level. The results suggest that release of DNA from the nuclear-membrane complex, induction of chromosome breaks, and cell inactivation are triggered by DSB. However, not simply a certain number of DSB in the DNA of the nucleus, but their cooperation within a small structural section of DNA is required for cell inactivation. Such sections may be the membrane-associated superstructure units. DSB produced under hypoxic conditions show a greater effectiveness than those produced under oxic conditions. The investigations with eukaryotic cells and bacteria suggest that not the entire DNA of all organisms but a structural unit common to them represents the critical target for radiation action. (author)

  5. Environmental radioactivity and radiation exposure in Switzerland 1995

    International Nuclear Information System (INIS)

    Voelkle, H.; Gobet, M.

    1996-01-01

    Switzerland has been performing systematic monitoring of radioactivity in the environment and in food for forty years. This report contains the results of measurements made in the course of 1995 and the consequential radiation doses for the population. The monitoring programme deals with radioactivity in the atmosphere, precipitation, aquatic systems, soil, grass, foodstuffs and the human body, but also includes natural radiation, doses due to radon inside dwellings, emissions from nuclear power stations and other operations using radionuclides, as well as miscellaneous radiation sources. All the nuclear power plants and other facilities licensed to handle radioactive substances remained within their annual release limits in 1995, and environmental measurements revealed no inadmissible immission or dose values. The population's mean annual radiation dose totals 4 mSv, with some 40% of this due to radon in the home (but with extreme values as high as 100 mSv), another 30% coming from natural radiation, a quarter from medical applications and less than 5% from artificial radiation. (author) figs., tabs., refs

  6. Occupational radiation exposure in Germany in 2006. Report of the radiation protection register

    International Nuclear Information System (INIS)

    Frasch, G.; Fritzsche, E.; Kammerer, L.; Karofsky, R.; Spiesl, J.; Stegemann, R.

    2008-06-01

    In Germany, persons occupationally exposed to radiation are monitored by several official dosimetric services who transmit their records about individual radiation doses to the Radiation Protection Register of the Federal Office for Radiation Protection (BfS). The number of dose recordings reported to the Radiation Protection Register has annually increased to more than three million records per year and thus accumulated to more than 34 million dose records at the end of 2006. The purpose of the Radiation Protection Register is to supervise the keeping of the dose limits by each radiation worker and to monitor the compliance with the radiation protection principle ''optimisation'' by performing detailed annual statistical analyses of the monitored persons and their radiation exposure. Amongst others, the annual report of the Radiation Protection Register provides information about status and development of occupational radiation exposure in Germany. In 2006, about 312,000 workers were monitored with dosimeters for occupational radiation exposure. About 18 % of the monitored persons received a measurable personal dose. The average annual dose of these exposed workers was 0.75 mSv. This value is the lowest average annual dose since dose monitoring for occupational worker was introduced. It remains below the dose limit of 1 mSv for the general public and amounts only 4 % of the annual dose limit of 20 mSv for radiation workers. Since 2003 aircraft crew personnel is subject to dose monitoring if it is employed in accordance with the German employment act and likely to receive an effective dose of at least 1 mSv per year from cosmic radiation during flight operation. This accounts for about 33.000 pilots and flight attendants. 45 airlines report the monthly accumulated dose values of their personnel via the Federal Office for Civil Aviation (''Luftfahrt-Bundesamt, LBA'') to the BfS. The collective dose of the aircraft crew personnel is 71 Person-Sv and thus

  7. Environmental policy. Ambient radioactivity levels and radiation doses in 1996

    International Nuclear Information System (INIS)

    1997-10-01

    The report is intended as information for the German Bundestag and Bundesrat as well as for the general population interested in issues of radiological protection. The information presented in the report shows that in 1996, the radiation dose to the population was low and amounted to an average of 4 millisievert (mSv), with 60% contributed by natural radiation sources, and 40% by artificial sources. The major natural source was the radioactive gas radon in buildings. Anthropogenic radiation exposure almost exclusively resulted from application of radioactive substances and ionizing radiation in the medical field, for diagnostic purposes. There still is a potential for reducing radiation doses due to these applications. In the reporting year, there were 340 000 persons occupationally exposed to ionizing radiation. Only 15% of these received a dose different from zero, the average dose was 1.8 mSv. The data show that the anthropogenic radiation exposure emanating from the uses of atomic energy or applications of ionizing radiation in technology is very low. (orig./CB) [de

  8. Potential radiation doses likely to be received by the radiologists and para medical staff in an hospital in Pakistan. (G. M. counter, survey meter measurements )

    International Nuclear Information System (INIS)

    Ali, A.; Zeb, J.; Iqbal, S.; Orfi, S.D.

    1999-01-01

    Potential radiation doses likely to received by the radiologists and paramedical staff in a typical hospital in Pakistan have been measured using a very sensitive radiation survey meter (FAG FH40F2) employing in Geiger Muller counter (FHZ 120] as a role which is extendable up to 4 meters in length. The measurements have been compared with internationally accepted Maximum Permissible Radiation Dos Level (MPDL). Radiation dose rates measured on the hands of two radiologist during fluoroscopy examination of the patient were of the order of 1 m Sv.h/sup -1/ and 540 u Sv. h/sup -1/ which were 400% to 21% higher than the MPDL (250 u Sv. h/sup -1/). Radiation dose rates measured on the chest of the nurses were 300 and 50 u Sv. h/sup -1/, which were 3000% to 500% higher than those of MPDL(10 u Sv. h/sup -1/). Such high dose rates present a serious situation from radiation damage point of view and deserve attention of the hospital management and of national regulatory authority so as to minimize the potential radiation doses to the radiologists and paramedical staff. As Low As Reasonably Achievable (ALARA) concept should be implemented in the health sector. (author)

  9. Replication of simian virus 40 in simian virus 40-transformed hamster kidney cells induced by mitomycin C or 60Co γ irradiation

    International Nuclear Information System (INIS)

    Rakusanova, T.; Smales, W.P.; Kaplan, J.C.; Black, P.H.

    1978-01-01

    Several clones of simian virus 40 (SV40)-transformed hamster kidney cells, which are heterogeneous for induction of infectious SV40, have been studied. SV40 yields are low after induction with 60 Co γ irradiation or mitomycin C. In order to clarify the mechanism(s) by which virus is produced in induced cells, we analyzed the replication of viral DNA and production of virion (V) antigen and infectious virus after induction in various clones as well as in lytically infected permissive cells. Cells replicating SV40 DNA or synthesizing V antigen were visualized by in situ hybridization and immunofluorescence techniques, respectively. Only some cells in induced cultures were found to produce SV40 and those which did were less efficient than lytically infected monkey cells. Mitomycin C or 60 Co γ irradiation acted by inducing more cells to replicate virus rather than by increasing the amount of SV40 released from individual cells. A greater proportion of cells could be induced to replicate SV40 DNA than to synthesize V antigen in all induced clones studied. Also, SV40 DNA replication was induced at lower doses of γ irradiation than the production of either V antigen or infectious virus suggesting that synthesis of late virus protein is more restricted in induced cells than is replication of SV40 DNA. These findings indicate that one of the effects of induction treatments on SV40-transformed hamster cells is an enhancement of the cells' capacity to support SV40 replication

  10. One-step simultaneous detection of Ureaplasma parvum and genotypes SV1, SV3 and SV6 from clinical samples using PlexPCR technology.

    Science.gov (United States)

    Payne, M S; Furfaro, L L; Tucker, R; Tan, L Y; Mokany, E

    2017-08-01

    Ureaplasma spp. are associated with preterm birth. In recent times, it has become apparent that Ureaplasma parvum, but not Ureaplasma urealyticum, is of most relevance. We recently demonstrated this in Australian pregnant women and using high-resolution melt (HRM) PCR, further showed that U. parvum genotype SV6 was of particular significance. However, our assay was unable to identify multiple genotypes in the same sample, required a separate species-level qPCR for low titre samples and was not ideal for diagnostic laboratories due to the nature of HRM PCR result interpretation. Consequently, our current study developed a novel, one-step PlexPCR assay capable of detecting U. parvum and genotypes SV1, SV3 and SV6 in a single reaction directly from clinical samples. We then validated this using vaginal swab DNA from our Australian cohort of pregnant women. The PlexPCR was highly sensitive, detecting all targets to between 0.4 × 10 -5  ng DNA (SV3) and 0.4 × 10 -6  ng DNA (U. parvum, SV1 and SV6). Compared to our HRM PCR, the PlexPCR defined genotype distribution in all seven cases previously reported as 'mixed', and detected another eight cases where multiple genotypes (two) were present in samples previously reported as single genotypes using HRM PCR. Ureaplasma spp. have been associated with prematurity for decades, however, only a minority of studies have examined this beyond the genus level. In those that have, Ureaplasma parvum has been strongly associated with preterm birth. We recently demonstrated this in Australian women and further showed that U. parvum genotype SV6 was of particular significance. Our PlexPCR assay allows rapid detection and concurrent genotyping of U. parvum in clinical samples and may be of particular interest to obstetricians, particularly those caring for women at a high risk of preterm birth, and any other disease phenotypes where U. parvum is of interest. © 2017 The Authors. Letters in Applied Microbiology published by John

  11. Commentaar op art. 563 Sv

    NARCIS (Netherlands)

    Knoops, G.G.J.; van Laanen, F.; Melai, A.L.; Groenhuijsen, M.S.

    2004-01-01

    Schrijvers verschaffen een wetenschappelijk commentaar op art. 563 Sv, betreffende de tenuitvoerlegging van andere straffen dan de bij art. 562 Sv bedoelde straffen ingeval van een veroordeelde wiens geestvermogens ziekelijk zijn gestoord.

  12. Mechanistic and kinetic aspects of microbial inactivation in food irradiation processes

    International Nuclear Information System (INIS)

    Tukenmez, I.

    2004-01-01

    Full text: A proper reaction mechanism was searched by analyzing the inactivation processes of microorganisms during food irradiation by ionizing radiation. By employing transition-state theory, it was assumed that the overall inactivation process involves a reversible sub-lethal stress and repair reactions to form reversibly injured cell or sensitized cell, which then undergoes irreversible injury leading to dead cell. A shoulder in low dose range in survival kinetics was associated with the repair process. Depending on the postulated mechanism, kinetic model equations were derived. The kinetics of cell inactivation by irradiation was expressed as depending on irradiation dose. By using experimental data in the developed model the inactivation parameters including threshold dose, radiation yield, decimal reduction dose and minimum sterilization dose were evaluated and microbial inactivation by irradiation was simulated by using the numerical values of the parameters. Developed model and model parameters may be used for the process control and the assessment of product quality in radiation preservation of food

  13. Potential radiation doses likely to be received by the radiologists and paramedical staff in typical hospital in Pakistan (GM counter, survey meter measurements) (abstract)

    International Nuclear Information System (INIS)

    Ali, A.; Zeb, J.; Iqbal, S.; Orfi, S.D.

    1998-01-01

    Potential radiation doses likely to be received by the radiologists and para medical staff in a typical hospital in Pakistan have been measured using a very sensitive radiation survey meter (FAG FH40F2) employing a Geiger Muller counter (FHZ120) as a probe which is a probe extend able up to 4 meters in length. These measurements have been compared with internationally accepted Maximum Permissible Radiation Dose Level (MPDL). Radiation dose rates measured on the hands of two radiologists during fluoroscopy examination of the patient were of the order of 1mSv.h/sup -1/ and 540 mu Sv.h/sup -1/ which were 400% to 216% times higher than the MPDL (250 mu Sv.h/sup -1/). Radiation dose rates measured on the chest and neck were 300 and 50 mu Sv.h/sup -1/, which were 3000% to 500% times higher than those of MPDL (10 mu Sv.h/sup -1/. Such high dose rates present a serious situation and deserve attention of the hospital management and of national regulatory authority so as to minimize the potential radiation doses to the radiologists and para medical staff. As Low As Reasonably Achievable (ALARA) concept should be implemented in the health sector. (author)

  14. Changes of ionizing radiation caused by natural radionuclides in the Curonian Spit

    International Nuclear Information System (INIS)

    Peciuliene, M.; Jasaitis, D.; Grigaliunaite-Vonseviciene, G. and others

    2005-01-01

    Taking into consideration a unique scenery of the Curonian Spit, dosimetric investigation of ionizing radiation caused by natural radionuclides is performed there. The influence of natural radionuclides present in the ground on the equivalent dose rate of gamma radiation in the ground surface air is established. Measurements of equivalent dose rate are carried out in the whole territory of the Curonian Spit in Lithuania. Especially numerous data have been collected on the coasts of the sea and bay, near them, in seaside dunes and by roads. The established equivalent dose rate values vary from 22 nSv/h (on the dune top) to 90 nSv/h (above an asphalt path). The values of the main gamma radiation source ( 40 K and 226 Ra) concentration are measured, and positive correlation of concentrations and equivalent dose rates in the ground surface air between 40 K and 2 '2 6 Ra is determinated. It is established that 40 K has the biggest influence on equivalent dose rate. The equivalent dose rate values in the ground surface air in the Curonian Spit are comparatively low (they can even be 1630 times lower in comparison to Guarapari beach, Brazil). (author)

  15. Precautionary radiation protection

    International Nuclear Information System (INIS)

    Heller, W.

    2006-01-01

    The German federal government annually reports about the development of radioactivity in the environment, providing the most important data and changes in environmental radioactivity and radiation exposure. These reports are based on the Act on Precautionary Protection of the Public against Radiation Exposure (Radiation Protection Provisions Act) of December 19, 1986 as a consequence of the Chernobyl reactor accident. The purpose of the Act is protection of the public from health hazards arising from a nuclear accident or any other event with comparable radiological consequences, and to create the foundations for correct evaluation of the risks resulting from specific radiation exposures. After 1986, the Act was soon given concrete shape by legal ordinances, which made it a workable tool. The following points, among others, can be summarized form the report for 2004: - The calculated natural and manmade overall exposure is 4.0 mSv/a, as in the previous year, and happens to be exactly the same figure as in the report for 1994. - The contribution to radiation exposure by nuclear power plants and other nuclear facilities is less than 0.01 mSv/a. Over a period of nearly twenty years, the Act and the annual reporting regime have proved to work. Standardized criteria prevent data abuse and misinterpretation, respectively. Definitions of limits have contributed to more transparency and more objectivity. (orig.)

  16. Monitoring of radiation situation in the territory of the Voronezh region

    Directory of Open Access Journals (Sweden)

    Yu. I. Stepkin

    2017-01-01

    Full Text Available The purpose of the study was to assess the doses of personnel and the population at the expense of all the main activities and sources of radiation in the territory of the Voronezh region. The data of the forms of state statistical supervision No. 1-DOZ “Information on the doses of personnel from persons under normal use of technogenic sources of ionizing radiation”, No. 3-DOZ “Information on radiation doses of patients during X-ray radiology studies”, No. 4-DOZ “Information on radiation doses of the population due to natural and technogenically altered background” for 2010-2016 and the radiation and hygienic passport of the territory of the Voronezh Region. Based on the results of monitoring the radiation situation, the situation associated with the impact of ionizing radiation sources in the Voronezh Region has been characterized as safe for the past 7 years. The average annual effective dose per 1 inhabitant due to all ionizing radiation remains stable with a slight upward trend and lies in the range from 2.925 (2010 to 3.399 mSv (2016. In the structure of the collective dose of the population of the Voronezh region, the dose from natural sources is 83.65%, from medical sources – 16.06%, from technogenically changed background radiation, including global fallout and accident at the Chernobyl nuclear power plant – 0.18%, from the activities of enterprises using Sources of ionizing radiation – 0.11%. The average annual effective dose of natural exposure to humans varies from 0.660 to 0.704 mSv / year, natural radiation from radon from 0.832 to 1.465 mSv / year. The average effective dose from medical research for the procedure for the study period was 0.27-0.40 mSv and tends to decrease due to the introduction of modern low-dose medical diagnostic equipment. On the territory of the Voronezh region, there were no population groups with an effective radiation dose exceeding 5 mSv / year. Gamma-background in the region in 2010

  17. Use of laser-UV for inactivation of virus in blood products

    International Nuclear Information System (INIS)

    Prodouz, K.N.; Fratantoni, J.C.; Boone, E.J.; Bonner, R.F.

    1987-01-01

    Inactivation of virus by UV radiation was examined as a potential method for sterilization of blood products. Samples of attenuated poliovirus, platelets and plasma were uniformly irradiated with a XeCl excimer laser that delivered 40 nsec pulses of UV at 308 nm (UVB308). Intensities and exposure does were varied from 0.11 to 1.40 MW/cm2 and 0.51 to 56.0 J/cm2, respectively. In studies conducted with low intensity UVB308 (less than or equal to 0.17 MW/cm2), using exposure doses greater than or equal to 10.8 J/cm2, it was possible to inactivate poliovirus by 4 to 6 log10. Platelets irradiated with doses less than or equal to 21.5 J/cm2 exhibited minimal damage as assessed by aggregation activity and spontaneous release of serotonin. Examination of the coagulation activity of irradiated plasma indicated that exposure doses less than or equal to 21.5 J/cm2 resulted in less than 20% increase in prothrombin and partial thromboplastin times. The use of UVB308 at a higher intensity (1.4 MW/cm2) over a similar range of exposure doses did not enhance viral inactivation but did result in increased damage to platelet and plasma proteins. These results demonstrate that at 308 nm there exists a window of efficacy for exposure doses between 10.8 and 21.5 J/cm2 and peak intensities less than or equal to 0.17 MW/cm2 in which a hardy virus is significantly inactivated and platelets and plasma proteins are, by functional criteria, minimally affected. Increased viral inactivation cannot be accomplished with higher UV intensities and will require additional or alternate measures

  18. 25 years of Chernobyl: Countermeasures are still required to keep radiation doses to reindeer herders under the recommended limits; 25 aar med Tsjernobyl: Mottiltak er framleis noedvendige for aa halde straaledosane til reindriftsutoevarane under tilraadde grenser

    Energy Technology Data Exchange (ETDEWEB)

    2011-07-01

    The government's goal was that no one should get radiation doses above 5 mSv the first year after the Chernobyl accident, and not more than 1 mSv per year in the following years. Radiation doses to reindeer herders in the most polluted areas in North-Troendelag and Nordland would have been about 10 mSv per year at most without all the measures that was initiated. From 1986 to 2009 was radiation doses to reindeer herders in Snaasa region reduced with approx. 70%, and in the Roeros region with approx. 40%. (AG)

  19. Radiation dose and radiation risk to foetuses and newborns during X-ray examinations

    Energy Technology Data Exchange (ETDEWEB)

    Kettunen, A. [Oulu Univ. (Finland)

    2004-05-01

    to a foetus was not calculated either before or after the pelvic x-ray examination of an expectant mother. The responsibility for counselling an expectant mother about the risk of a radiation dose to the foetus was not determined. In conventional pelvic x-ray examinations, the dose to the foetus varied from 1 to 2 mSv/exposure. A proposal for a guide to good practices in the pelvic x-ray examination of women of reproductive age is given. The effective doses of 118 chest x-ray examinations to 43 newborns (gestational age from 26 to 42 weeks) were estimated. The effective dose from one chest radiograph varied from 7.5 {mu}Sv to 54 {mu}Sv. Retrospectively, the total number of radiation examinations to these newborns totalled 399 during the study; the mean was 9.3 (range 1-40). 98% of the examinations were produced during the first treatment period after birth. The total effective dose per child varied from 0.31 mSv to 3.7 mSv. The radiation risk of fatal childhood cancer due to the mean dose of 0.37 mSv is 3.7*10 -5. (orig.)

  20. Radiation dose and radiation risk to foetuses and newborns during X-ray examinations

    International Nuclear Information System (INIS)

    Kettunen, A.

    2004-05-01

    foetus was not calculated either before or after the pelvic x-ray examination of an expectant mother. The responsibility for counselling an expectant mother about the risk of a radiation dose to the foetus was not determined. In conventional pelvic x-ray examinations, the dose to the foetus varied from 1 to 2 mSv/exposure. A proposal for a guide to good practices in the pelvic x-ray examination of women of reproductive age is given. The effective doses of 118 chest x-ray examinations to 43 newborns (gestational age from 26 to 42 weeks) were estimated. The effective dose from one chest radiograph varied from 7.5 μSv to 54 μSv. Retrospectively, the total number of radiation examinations to these newborns totalled 399 during the study; the mean was 9.3 (range 1-40). 98% of the examinations were produced during the first treatment period after birth. The total effective dose per child varied from 0.31 mSv to 3.7 mSv. The radiation risk of fatal childhood cancer due to the mean dose of 0.37 mSv is 3.7*10 -5. (orig.)

  1. Acute Radiation Syndrome. Consequences and outcomes

    International Nuclear Information System (INIS)

    Okladnikova, N.D.; Pesternikova, V.S.; Sumina, M.V.; Azizova, T.V.; Yurkov, N.N.

    2000-01-01

    The consequences and outcomes of an Acute Radiation Syndrome (ARS), induced by external gamma radiation for 59 persons (49 men and 10 women) have been estimated. All incidents have taken place more than 40 years ago in the yearly years of adjustment of an atomic industry (1950-1953-38 persons, 1954-1958-21 persons). According to the degree of severity ARS 5 groups are selected: the severest degree - 7 individuals (average dose in group 43.8±12.8 Sv), severe - 4 individuals (9.3±1.5 Sv), medium - 14 individuals (2.2±0.8 Sv), a light degree - 15 individuals (0.93±0.13 Sv), ''erased'' from - 19 individuals (0.85±0.07 Sv). In all cases, except for lethal (the severest degree), the characteristics of morphological composition of the peripheral blood were restored in the first year after ARS and now correspond to physiological standard. In 2 cases the moderate hypoplasia of granulocytopoiesis was diagnosed. A marker of the acute exposure was the chromosome aberrations in lymphocytes of the peripheral blood. The frequency of chromosome aberrations correlates with severity degree of ARS (from 3-7 up to 35-50 stable aberrations per 100 cells). In cases of ARS with severe degree the early development of a cerebral atherosclerosis is detected. The radiation cataract was diagnosed in 5 patients (an exposure doses 4.0-9.8 Sv, a period of development 2-5 years). During the first years after ARS in 80% of cases the complete labour rehabilitation is reached. Of 53 patients with known vital status by 45 year of monitoring 19 persons (35.8%) have died, of these in 2 cases the causes of death are not determined. In remaining cases the causes of death were ARS of severest degree (7 persons), Ischemic Heart Disease (5 persons), malignant tumors (4 persons), accidents and traumas (2 persons). (author)

  2. Regulatory proteins (inhibitors or activators) affect estimates of Msub(r) of enzymes and receptors by radiation inactivation

    International Nuclear Information System (INIS)

    Potier, M.; Giroux, S.

    1985-01-01

    The radiation-inactivation method allows the determination of the Msub(r) of enzymes and receptors by monitoring the decay of biological activity as a function of absorbed dose. The presence of regulatory or effector proteins (inhibitors or activators) associated with an enzyme or receptor, or released in the preparation after tissue homogenization, may affect the decay of biological activity. How the activity is affected, however, will depend on the type of inhibition (competitive or non-competitive), the inhibitor or activator concentration, the dissociation constant of the enzyme-effector system, and the effector Msub(r) relative to that of the enzyme. Since little is known on how effector proteins influence radiation inactivation of enzymes and receptors, we have considered a theoretical model in an effort to provide a framework for the interpretation of experimentally obtained data. Our model predicts that competitive and non-competitive inhibitors of enzymes could be distinguished by analysing irradiated samples with various substrate concentrations. Inhibitors will decrease whereas activators will increase the apparent target size of enzymes or receptors. (author)

  3. Natural radioactivity contents in tobacco and radiation dose induced from smoking

    International Nuclear Information System (INIS)

    Shousha, H. A.; Ahmad, F.

    2012-01-01

    One of the causative factors for cancer-inducing mechanisms in humans is radioactive elements present in tobacco leaves used in the manufacture of cigarettes. Smoking of tobacco and its products increases the internal intake and radiation dose due to naturally occurring radionuclides that are considered to be one of the most significant causes of lung cancer. In this work, different commercial types of cigarettes, cigar and moassel were collected from market. Naturally occurring radionuclides 226 Ra and 214 Bi ( 238 U series), 228 Ac and 228 Ra ( 232 Th series), 40 K and man-made 137 Cs were measured in tobacco using gamma-ray spectrometer. Results show that the average concentrations of 238 U, 232 Th and 40 K were 4.564, 3.940 and 1289.53 Bq kg -1 , respectively. This reflects their origin from the soil by root uptake and fertilisers used in the cultivation of tobacco plants. Concentration of 137 Cs was 0.348 Bq kg -1 due to root uptake or deposition onto the leaf foliage. For smokers, the annual effective dose due to inhalation of 238 U varied from 49.35 to 139.40 μSv -1 (average 104.27 μSv y -1 ), while of 232 Th from 23.86 to 111.06 μSv y -1 (average 65.52 μSv y -1 ). The annual effective dose resulting from 137 Cs was varied from 10.96 to 24.01 nSv y -1 (average 19.41 nSv y -1 ). (authors)

  4. Impact of robotics and a suspended lead suit on physician radiation exposure during percutaneous coronary intervention

    Energy Technology Data Exchange (ETDEWEB)

    Madder, Ryan D., E-mail: ryan.madder@spectrumhealth.org; VanOosterhout, Stacie; Mulder, Abbey; Elmore, Matthew; Campbell, Jessica; Borgman, Andrew; Parker, Jessica; Wohns, David

    2017-04-15

    Background: Reports of left-sided brain malignancies among interventional cardiologists have heightened concerns regarding physician radiation exposure. This study evaluated the impact of a suspended lead suit and robotic system on physician radiation exposure during percutaneous coronary intervention (PCI). Methods: Real-time radiation exposure data were prospectively collected from dosimeters worn by operating physicians at the head- and chest-level during consecutive PCI cases. Exposures were compared in three study groups: 1) manual PCI performed with traditional lead apparel; 2) manual PCI performed using suspended lead; and 3) robotic PCI performed in combination with suspended lead. Results: Among 336 cases (86.6% manual, 13.4% robotic) performed over 30 weeks, use of suspended lead during manual PCI was associated with significantly less radiation exposure to the chest and head of operating physicians than traditional lead apparel (chest: 0.0 [0.1] μSv vs 0.4 [4.0] μSv, p < 0.001; head: 0.5 [1.9] μSv vs 14.9 [51.5] μSv, p < 0.001). Chest-level radiation exposure during robotic PCI performed in combination with suspended lead was 0.0 [0.0] μSv, which was significantly less chest exposure than manual PCI performed with traditional lead (p < 0.001) or suspended lead (p = 0.046). In robotic PCI the median head-level exposure was 0.1 [0.2] μSv, which was 99.3% less than manual PCI performed with traditional lead (p < 0.001) and 80.0% less than manual PCI performed with suspended lead (p < 0.001). Conclusions: Utilization of suspended lead and robotics were observed to result in significantly less radiation exposure to the chest and head of operating physicians during PCI. - Highlights: • Use of suspended lead during manual PCI reduced cranial radiation among operators by 97%. • Robotic PCI reduced cranial radiation among operators by 99%. • Suspended lead and robotics together achieved the lowest levels of radiation exposure.

  5. Impact of robotics and a suspended lead suit on physician radiation exposure during percutaneous coronary intervention

    International Nuclear Information System (INIS)

    Madder, Ryan D.; VanOosterhout, Stacie; Mulder, Abbey; Elmore, Matthew; Campbell, Jessica; Borgman, Andrew; Parker, Jessica; Wohns, David

    2017-01-01

    Background: Reports of left-sided brain malignancies among interventional cardiologists have heightened concerns regarding physician radiation exposure. This study evaluated the impact of a suspended lead suit and robotic system on physician radiation exposure during percutaneous coronary intervention (PCI). Methods: Real-time radiation exposure data were prospectively collected from dosimeters worn by operating physicians at the head- and chest-level during consecutive PCI cases. Exposures were compared in three study groups: 1) manual PCI performed with traditional lead apparel; 2) manual PCI performed using suspended lead; and 3) robotic PCI performed in combination with suspended lead. Results: Among 336 cases (86.6% manual, 13.4% robotic) performed over 30 weeks, use of suspended lead during manual PCI was associated with significantly less radiation exposure to the chest and head of operating physicians than traditional lead apparel (chest: 0.0 [0.1] μSv vs 0.4 [4.0] μSv, p < 0.001; head: 0.5 [1.9] μSv vs 14.9 [51.5] μSv, p < 0.001). Chest-level radiation exposure during robotic PCI performed in combination with suspended lead was 0.0 [0.0] μSv, which was significantly less chest exposure than manual PCI performed with traditional lead (p < 0.001) or suspended lead (p = 0.046). In robotic PCI the median head-level exposure was 0.1 [0.2] μSv, which was 99.3% less than manual PCI performed with traditional lead (p < 0.001) and 80.0% less than manual PCI performed with suspended lead (p < 0.001). Conclusions: Utilization of suspended lead and robotics were observed to result in significantly less radiation exposure to the chest and head of operating physicians during PCI. - Highlights: • Use of suspended lead during manual PCI reduced cranial radiation among operators by 97%. • Robotic PCI reduced cranial radiation among operators by 99%. • Suspended lead and robotics together achieved the lowest levels of radiation exposure.

  6. Effects of radiation and chemicals on SV40 oncogenesis. Final progress report

    International Nuclear Information System (INIS)

    Coggin, J.H. Jr.

    1982-05-01

    This project is directed toward developing rapid, quantitative methods and immunologic markers which will permit the early detection of newly forming tumors induced or enhanced by x-irradiation, chemical carcinogens, viruses or combinations of the three. The projects under study in our ongoing collaborative program seek to develop the detailed understanding and precise methodology required for the early detection of embryonic antigens in transformed cells induced by the co-carcinogenic effects of viruses and low-level radiation. A new technique for assaying the earliest transformed cells appearing in a carcinogen treated population affords a unique tool for this study. Present plans involve efforts to purify embryonic determinants from fetal and transformed cells of hamsters and mice in order to define their role in the transformation process and in tumor development

  7. Exposure of the orthopaedic surgeon to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Katoh, Kiyonobu; Koga, Takamasa; Matsuzaki, Akio; Kido, Masaki; Satoh, Tetsunori [Fukuoka Univ. (Japan). Chikushi Hospital

    1995-09-01

    We monitored the amount of radiation received by surgeons and assistants during surgery carried out with fluoroscopic assistance. The radiation was monitored with the use of MYDOSE MINIX PDM107 made by Aloka Co. Over a one year period from Aug 20, 1992 to Aug 19, 1993, a study was undertaken to evaluate exposure of the groin level to radiation with or without use of the lead apron during 106 operation (Group-1). In another group, radiation was monitored at the breast and groin level outside of the lead apron during 39 operations (Group-2). In Group-1, the average exposure per person during one year was 46.0 {mu}SV and the average exposure for each procedure was 1.68 {mu}SV. The use of the lead apron affirmed its protective value; the average radiation dose at the groin level out-side of the apron was 9.11 {mu}SV, the measured dose beneath the apron 0.61 {mu}SV. The average dose of exposure to the head, breast at groin level outside of the lead apron, were 7.68 {mu}SV, 16.24 {mu}SV, 32.04 {mu}SV respectively. This study and review of the literature indicate that the total amount of radiation exposure during surgery done with fluoroscopic control remains well within maximum exposure limits. (author).

  8. Exposure of the orthopaedic surgeon to radiation

    International Nuclear Information System (INIS)

    Katoh, Kiyonobu; Koga, Takamasa; Matsuzaki, Akio; Kido, Masaki; Satoh, Tetsunori

    1995-01-01

    We monitored the amount of radiation received by surgeons and assistants during surgery carried out with fluoroscopic assistance. The radiation was monitored with the use of MYDOSE MINIX PDM107 made by Aloka Co. Over a one year period from Aug 20, 1992 to Aug 19, 1993, a study was undertaken to evaluate exposure of the groin level to radiation with or without use of the lead apron during 106 operation (Group-1). In another group, radiation was monitored at the breast and groin level outside of the lead apron during 39 operations (Group-2). In Group-1, the average exposure per person during one year was 46.0 μSV and the average exposure for each procedure was 1.68 μSV. The use of the lead apron affirmed its protective value; the average radiation dose at the groin level out-side of the apron was 9.11 μSV, the measured dose beneath the apron 0.61 μSV. The average dose of exposure to the head, breast at groin level outside of the lead apron, were 7.68 μSV, 16.24 μSV, 32.04 μSV respectively. This study and review of the literature indicate that the total amount of radiation exposure during surgery done with fluoroscopic control remains well within maximum exposure limits. (author)

  9. Occupational radiation exposure in Germany in 2011. Report of the radiation protection register; Die berufliche Strahlenexposition in Deutschland 2011. Bericht des Strahlenschutzregisters

    Energy Technology Data Exchange (ETDEWEB)

    Frasch, Gerhard; Kammerer, Lothar; Karofsky, Ralf; Mordek, Else; Schlosser, Andrea; Spiesl, Josef

    2013-04-15

    In Germany, persons who are occupationally exposed to ionising radiation are monitored by several official dosimetry services that transmit the dose records about individual radiation monitoring to the Radiation Protection Register of the Federal Office for Radiation Protection (BfS). The purpose of the Radiation Protection Register is to supervise the keeping of the dose limits and to monitor the compliance with the radiation protection principle ''Optimisation'' by performing detailed annual statistical analyses of the monitored persons and their radiation exposure. The annual report of the Radiation Protection Register provides information about status and development of occupational radiation exposure in Germany. In 2011, about 350,000 workers were monitored with dosemeters for occupational radiation exposure. The number increased during the past five years continuously by 10 %. Only 19 % of the monitored persons received measurable personal doses. The average annual dose of these exposed workers was 0.58 mSv corresponding to 3 % of the annual dose limit of 20 mSv for radiation workers. In total, 7 persons exceeded the annual dose limit of 20 mSv, i.e. two cases per 100,000 monitored persons. The collective dose of the monitored persons decreased to 38.5 Person-Sv, the lowest value since the last fifty years of occupational dose monitoring. In 2010, 45 airlines calculated the route doses of 39,000 members of the aircraft crew personnel by using certified computer programmes for dose calculation and sent the accumulated monthly doses via the Federal Office for Civil Aviation (''Luftfahrt-Bundesamt, LBA'') to the BfS. The collective dose of the aircraft crew personnel is 83 person-Sv, and thus significantly higher than the total collective dose of the workers monitored with personal dosemeters (38.5 person-Sv). The annual average dose of aircraft crew personnel was 2.12 mSv and decreased compared to 2010 (2,30 mSv). In 2011

  10. Impact of robotics and a suspended lead suit on physician radiation exposure during percutaneous coronary intervention.

    Science.gov (United States)

    Madder, Ryan D; VanOosterhout, Stacie; Mulder, Abbey; Elmore, Matthew; Campbell, Jessica; Borgman, Andrew; Parker, Jessica; Wohns, David

    Reports of left-sided brain malignancies among interventional cardiologists have heightened concerns regarding physician radiation exposure. This study evaluated the impact of a suspended lead suit and robotic system on physician radiation exposure during percutaneous coronary intervention (PCI). Real-time radiation exposure data were prospectively collected from dosimeters worn by operating physicians at the head- and chest-level during consecutive PCI cases. Exposures were compared in three study groups: 1) manual PCI performed with traditional lead apparel; 2) manual PCI performed using suspended lead; and 3) robotic PCI performed in combination with suspended lead. Among 336 cases (86.6% manual, 13.4% robotic) performed over 30weeks, use of suspended lead during manual PCI was associated with significantly less radiation exposure to the chest and head of operating physicians than traditional lead apparel (chest: 0.0 [0.1] μSv vs 0.4 [4.0] μSv, probotic PCI performed in combination with suspended lead was 0.0 [0.0] μSv, which was significantly less chest exposure than manual PCI performed with traditional lead (probotic PCI the median head-level exposure was 0.1 [0.2] μSv, which was 99.3% less than manual PCI performed with traditional lead (probotics were observed to result in significantly less radiation exposure to the chest and head of operating physicians during PCI. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. A micro-controller based palm-size radiation monitor

    International Nuclear Information System (INIS)

    Bhingare, R.R.; Bajaj, K.C.; Kannan, S.

    2001-01-01

    A micro-controller based, palm-size radiation monitor, PALMRAD, using a silicon P-N junction diode as a detector has been developed. It is useful for radiation protection monitoring during radiation emergency as well as radioactive source loading operations. Some of the features of PALMRAD developed are the use of a semiconductor diode as the detector, simultaneous display of integrated dose and dose rate on a 16-digit alpha numeric LCD display, measurable integrated dose range from 1 μSv to 5000 μSv and dose rate range from 1 mSv/h to 1,000 mSv/h, RS 232C serial interface for connection to a Personal Computer,-storage of integrated dose and dose rate readings, recall of stored readings on LCD display, presentable integrated dose alarm from 1 μSv to 5000 μSv and dose rate from 1 mSv/h to 1,000 mSv/h, battery status and memory status check during measurement, LCD display with LED back-lighting, etc. (author)

  12. Environmental policy. Ambient radioactivity levels and radiation doses in 1996; Umweltpolitik. Umweltradioaktivitaet und Strahlenbelastung im Jahr 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    The report is intended as information for the German Bundestag and Bundesrat as well as for the general population interested in issues of radiological protection. The information presented in the report shows that in 1996, the radiation dose to the population was low and amounted to an average of 4 millisievert (mSv), with 60% contributed by natural radiation sources, and 40% by artificial sources. The major natural source was the radioactive gas radon in buildings. Anthropogenic radiation exposure almost exclusively resulted from application of radioactive substances and ionizing radiation in the medical field, for diagnostic purposes. There still is a potential for reducing radiation doses due to these applications. In the reporting year, there were 340 000 persons occupationally exposed to ionizing radiation. Only 15% of these received a dose different from zero, the average dose was 1.8 mSv. The data show that the anthropogenic radiation exposure emanating from the uses of atomic energy or applications of ionizing radiation in technology is very low. (orig./CB) [Deutsch] Der vorliegende Bericht ueber die `Umweltradioaktivitaet und Strahlenbelastung im Jahr 1996` richtet sich an Bundestag und Bundesrat und darueber hinaus an alle an Fragen des Strahlenschutzes interessierte Buerger. Der Bericht belegt, dass die Strahlenbelastung der Bevoelkerung im Jahr 1996 gering war und insgesamt durchschnittlich 4 Millisievert (mSv) betrug. Dieser Wert war zu 60% auf natuerliche und zu 40% auf kuenstliche Strahlenquellen zurueckzufuehren. Den wesentlichen Beitrag zur natuerlichen Strahlenbelastung lieferte das radioaktive Gas Radon in Wohnungen. Die zivilisatorische Strahlenexposition der Bevoelkerung wurde fast ausschliesslich durch die Anwendung radioaktiver Stoffe und ionisierender Strahlen in der Medizin im Rahmen der Diagnostik hervorgerufen. Hier bestehen nach wie vor Moeglichkeiten zur Reduktion der Strahlenbelastung. Im Jahre 1996 waren 340 000 Personen beruflich

  13. Effects of radiation; Effets des radiations

    Energy Technology Data Exchange (ETDEWEB)

    Masse, R [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France)

    2006-07-01

    The medical consequences of a whole-body irradiation come from the destruction of cells and inflammatory reactions it provokes. The most sensitive organs are the tissues that actively split. The embryo is particularly sensitive, from 200 mSv for the effects on the brain development. The reproduction functions are reached for man from 2000 mSv, the ovary sensitivity is less, the oocytes do not split after the fetus life. For adult the bone marrow outrage leads to the disappearing of blood cells (4000 mSv). The doses from 6000 to 10000 mSv lead the failure of the digestive system and lung. for the upper doses every tissue is reached, particularly by the effects on cells of blood vessels. Important brain dysfunctions appear beyond 10000 mSv. As regards the delayed effects of overexposures the epidemiology brings to light sanitary consequences of the exposure of the population to the ionizing radiations and requires that all the possible factors associated for that purpose are considered. About hereditary effects, it appears that moderate acute radiation exposures of even a relatively large human population must have little impact, in spite of the rate of spontaneous congenital deformations is of the order of 6 %. For the induction of cancers, it is not observed excess for doses lower than 200 mSv for adults and 100 mSv for children (the populations studied are survival people of hiroshima and Nagasaki, patients treated by irradiation, uranium miners, children exposed to radioactive iodine after Chernobylsk accident). To simplify an expression of the risk has been fixed to 5% of induced cancer by Sv for population and 4% by Sv for workers, the different being explained by the demography and the sensitivity of the youngest age groups. As regards the low doses of radiations, a bundle of convergent epidemiological observations notices the absence of effects of the low doses rates. Biological mechanisms, notably of repair are approached, then certain accidents (Goiania

  14. Effects of radiation; Effets des radiations

    Energy Technology Data Exchange (ETDEWEB)

    Masse, R. [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France)

    2006-07-01

    The medical consequences of a whole-body irradiation come from the destruction of cells and inflammatory reactions it provokes. The most sensitive organs are the tissues that actively split. The embryo is particularly sensitive, from 200 mSv for the effects on the brain development. The reproduction functions are reached for man from 2000 mSv, the ovary sensitivity is less, the oocytes do not split after the fetus life. For adult the bone marrow outrage leads to the disappearing of blood cells (4000 mSv). The doses from 6000 to 10000 mSv lead the failure of the digestive system and lung. for the upper doses every tissue is reached, particularly by the effects on cells of blood vessels. Important brain dysfunctions appear beyond 10000 mSv. As regards the delayed effects of overexposures the epidemiology brings to light sanitary consequences of the exposure of the population to the ionizing radiations and requires that all the possible factors associated for that purpose are considered. About hereditary effects, it appears that moderate acute radiation exposures of even a relatively large human population must have little impact, in spite of the rate of spontaneous congenital deformations is of the order of 6 %. For the induction of cancers, it is not observed excess for doses lower than 200 mSv for adults and 100 mSv for children (the populations studied are survival people of hiroshima and Nagasaki, patients treated by irradiation, uranium miners, children exposed to radioactive iodine after Chernobylsk accident). To simplify an expression of the risk has been fixed to 5% of induced cancer by Sv for population and 4% by Sv for workers, the different being explained by the demography and the sensitivity of the youngest age groups. As regards the low doses of radiations, a bundle of convergent epidemiological observations notices the absence of effects of the low doses rates. Biological mechanisms, notably of repair are approached, then certain accidents (Goiania

  15. Radiation protection of aviation personnel at exposure by cosmic radiation

    International Nuclear Information System (INIS)

    Vicanova, M.; Pinter, I.; Liskova, A.

    2008-01-01

    For determination of radiation dose of aviation personnel we used the software EPCARD (European Program Package for the Calculation of Aviation Route Doses) developed by National Research Center for Environmental Health - Institute of Radiation Protection (Neuherberg, Germany) and the software CARI 6, developed by the FAA's Civil Aerospace Medical Institute (USA). Both codes are accomplished by the Joint Aviation Authorities. Experimental measurement and estimation of radiation doses of aviation personnel at exposure by cosmic radiation were realised in the period of lowered solar activity. All-year effective dose of pilots, which worked off at least 11 months exceeds the value 1 mSv in 2007. The mean all-year effective dose of member of aviation personnel at exposure by cosmic radiation is 2.5 mSv and maximal all-year effective dose, which we measured in 2007 was 4 mSv. We assumed that in the period of increased solar activity the all-year effective doses may by higher

  16. Does oxygen enhance the radiation: induced inactivation of penicillinase. Progress report, December 1, 1979-November 30, 1980

    International Nuclear Information System (INIS)

    Samuni, A.; Kalkstein, A.; Czapski, G.

    1980-01-01

    The radiation-induced inactivation of penicillinase in dilute aqueous solutions buffered with phosphate was studied, by examining enzyme radiosensitivity in the presence of various gases (He, O 2 , H 2 , N 2 O, N 2 O + O 2 ). The introduction of either N 2 O or O 2 was found to reduce the radiodamage. On the other hand H 2 or N 2 O + O 2 gas-mixture enhanced the radiosensitivity. In the presence of formate and oxygen, no enzyme inactivation was detected. The results indicated that the specific damaging efficiency of H atoms is almost four-fold higher than that of OH radical; therefore in phosphate buffer, where more than half of the free radicals are H atoms, it is the H radicals that are responsible for the majority of the damage. The superoxide radicals appeared to be completely inactive and did not contribute toward enzyme inactivation. Oxygen was shown to affect the radiosensitivity in two ways. On one side, it protected by converting e - /sub aq/ and H radicals into harmless O 2 - radicals. On the other side it increased the inactivation by enhancing the damage brought about by OH radicals (OER = 2.8). In the present case the oxygen effect of protection exceeded that of sensitization, thus giving rise to a moderate overall protection effect

  17. Response of bacteria in wastewater sludge to moisture loss by evaporation and effect of moisture content on bacterial inactivation by ionizing radiation

    International Nuclear Information System (INIS)

    Ward, R.L.; Yeager, J.G.; Ashley, C.S.

    1981-01-01

    Two studies were carried out to determine the influence of moisture content on the survival of bacteria in raw wastewater sludge. The first study involved the effect of water loss by evaporation on the bacterial population. The second used these dewatered samples to measure the effects of moisture content on the inactivation of bacteria in sludge by ionizing radiation. Both studies involved survival measurements of six representative fecally associated bacteria grown separately in sterilized sludge as well as survival data on bacteria indigenous to sludge. Growth of bacteria was stimulated in sludge during the initial phase of moisture removal by evaporation, but the reduction of moisture content below about 50% by weight caused a proportional decrease in bacterial numbers. The rates of inactivation of bacteria by ionizing radiation in sludge were usually modified to some degree by variations in moisture content. Most bacteria were found to be somewhat protected from ionizing radiation at reduced moisture levels

  18. Radiation practices 1996

    International Nuclear Information System (INIS)

    Havukainen, R.

    1997-05-01

    At the end of 1996, there were 1,762 valid safety licences in Finland for the use of radiation. In addition, there were 2,052 responsible parties for dental x-ray diagnostics. The registry of the Finnish Centre for Radiation and Nuclear Safety listed 13,360 radiation sources and 313 radionuclide laboratories. The import of radioactive substances amounted to 1.14 x 10 +16 Bq and export to 7.78 x 10 +13 Bq. A total of 4.02 x 10 +13 Bq of short-lived radionuclides were produced in Finland. There were 11,842 workers monitored for radiation exposure at 1,352 work sites. Of these employees, 27% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of individual dosimeter readings) was 7.96 manSv in 1996, with nuclear power plant workers accounting for 69% of this total. The annual dosimeter reading of ten medical doctors (radiologists, interventional radiologists and cardiologists) and eight nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of dosimeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 242 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations where unusually high exposure to radiation was an unavoidable part of the task. Report was made of 12 incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Five of these cases occurred in radiotherapy, three in use of a radiation source in industry, three in transport of radiation sources and one in use of solarium appliances. Radiation-contaminated material was found in 17 shipments of scrap. (orig.)

  19. Radiation practices 1996

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.

    1997-05-01

    At the end of 1996, there were 1,762 valid safety licences in Finland for the use of radiation. In addition, there were 2,052 responsible parties for dental x-ray diagnostics. The registry of the Finnish Centre for Radiation and Nuclear Safety listed 13,360 radiation sources and 313 radionuclide laboratories. The import of radioactive substances amounted to 1.14 x 10{sup +16} Bq and export to 7.78 x 10{sup +13} Bq. A total of 4.02 x 10{sup +13} Bq of short-lived radionuclides were produced in Finland. There were 11,842 workers monitored for radiation exposure at 1,352 work sites. Of these employees, 27% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of individual dosimeter readings) was 7.96 manSv in 1996, with nuclear power plant workers accounting for 69% of this total. The annual dosimeter reading of ten medical doctors (radiologists, interventional radiologists and cardiologists) and eight nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of dosimeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 242 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations where unusually high exposure to radiation was an unavoidable part of the task. Report was made of 12 incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Five of these cases occurred in radiotherapy, three in use of a radiation source in industry, three in transport of radiation sources and one in use of solarium appliances. Radiation-contaminated material was found in 17 shipments of scrap. (orig.)

  20. Radiation risk perception by radiation professionals. Survey results just before the radiological accident at the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant

    International Nuclear Information System (INIS)

    Miura, Miwa; Hayashida, Rika; Takao, Hideaki; Matsuda, Naoki; Ono, Koji

    2013-01-01

    From October to December 2010, just before the radiological accident at the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant, 71 radiation professionals belonging to the radiation facilities in Japan were asked what they consider as a 'safe' dose of radiation for themselves, their spouse, parents, children, brothers and friends. Although the 'safe' dose varied widely from less than 1 mSv/y to higher than 100 mSv/y, the average dose was 35.6 mSv/y that was around the middle point between the exposure dose limits for annual average (20 mSv/y) and for any single year (50 mSv/y). Similar results were obtained from another surveys for the members of Japan Radioisotope Association (36.9 mSv/y) and for the Oita Prefectural Hospital (36.8 mSv/y). Among the family members and friends, the minimum average 'safe' dose was 8.5 mSv/y for children, to whom 50% of responders claimed the 'safe' dose less than 1 mSv. Gender, age and specialty of the responder also affected the 'safe' dose. These findings suggest that the perception of radiation risk varies widely and that the legal exposure dose limit derived from the regulatory science may act as an anchor of safety even in radiation professionals. The different level of risk perception for different target groups in radiation professionals appears similar to those in non-professional whole population. The gap between these characteristics of real radiation professionals and the generally accepted picture of radiation professionals might take a part in a state of confusion after the radiological accident. (author)

  1. Inactivation of prion infectivity by ionizing rays

    Energy Technology Data Exchange (ETDEWEB)

    Gominet, M. [Ionisos, ZI les Chatinieres, F01120 Dagneux (France); Vadrot, C.; Austruy, G. [Paris V University, Central Pharmacy of Hospitals, 4 avenue de l' Observatoire, F-75006, Paris (France); Darbord, J.C. [Paris V University, Central Pharmacy of Hospitals, 4 avenue de l' Observatoire, F-75006, Paris (France)], E-mail: darbord@pharmacie.univ-paris5.fr

    2007-11-15

    Inactivation of prion deposits on medical devices or prion contamination in pharmaceutical raw materials is considered as impossible by using gamma irradiation. Early, the guideline WHO/CDS/CSR/APH/2000 has described irradiation as an ineffective process. But, in 2003, S. Miekka et al. noted radiation inactivation of prions in a particular application to purify human albumin, shown by the physical denaturation of the infectious protein (PrP). The aim of our study was to determine the inactivation of prions with a scrapie model (strain C506M3) by irradiating standardised preparations. Results: Gamma irradiation was partially effective, showing a 4-5 log reduction on exposure to 50 kGy. A characteristic effect-dose curve was not observed (25, 50 and 100 kGy), only an increase in the incubation period of the murine disease (229 days with 25 kGy to 290 days with 100 kGy) compared with 170 days without irradiation. Since the inactivation was not a total one, the observed effect is significant. It is proposed that further work be undertaken with the model to investigate the application of gamma radiation known levels of prion contamination.

  2. Inactivation of prion infectivity by ionizing rays

    International Nuclear Information System (INIS)

    Gominet, M.; Vadrot, C.; Austruy, G.; Darbord, J.C.

    2007-01-01

    Inactivation of prion deposits on medical devices or prion contamination in pharmaceutical raw materials is considered as impossible by using gamma irradiation. Early, the guideline WHO/CDS/CSR/APH/2000 has described irradiation as an ineffective process. But, in 2003, S. Miekka et al. noted radiation inactivation of prions in a particular application to purify human albumin, shown by the physical denaturation of the infectious protein (PrP). The aim of our study was to determine the inactivation of prions with a scrapie model (strain C506M3) by irradiating standardised preparations. Results: Gamma irradiation was partially effective, showing a 4-5 log reduction on exposure to 50 kGy. A characteristic effect-dose curve was not observed (25, 50 and 100 kGy), only an increase in the incubation period of the murine disease (229 days with 25 kGy to 290 days with 100 kGy) compared with 170 days without irradiation. Since the inactivation was not a total one, the observed effect is significant. It is proposed that further work be undertaken with the model to investigate the application of gamma radiation known levels of prion contamination

  3. Effect of Coat Layers in Bacillus Subtilis Spores Resistance to Photo-Catalytic Inactivation

    Directory of Open Access Journals (Sweden)

    Luz del Carmen Huesca-Espitia

    2017-10-01

    Full Text Available Different water treatment processes (physical and chemical exist to obtain safe water for human or food industry supply. The advanced oxidation technologies are rising as a new alternative to eliminate undesirable chemicals and waterborne diseases. In this work, we analyze the power of the photo-assisted Fenton process using Fe(II/H2O2 and UV radiation (365 nm to inactivate Bacillus subtilis spores, considered among the most resistant biological structures known. Different concentrations of Fe(II, H2O2 and UV radiation (365 nm were used to inactivate wt and some coat spore mutants of B. subtilis. Wt spores of B. subtilis were inactivated after 60 min using this process. In general, all defective coat mutants were more sensitive than the wt spores and, particularly, the double mutant was 10 folds more sensitive than others being inactivated during the first 10 minutes using soft reaction conditions. Presence of Fe(II ions was found essential for spore inactivating process and, for those spores inactivated using the Fe(II/H2O2 under UV radiation process, it is suggested that coat structures are important to their resistance to the treatment process. The photo-assisted Fenton process using Fe(II, H2O2 and UV radiation (365 nm can be used to inactivate any water microorganisms with the same or less resistance that B. subtilis spores to produce safe drinking water in relatively short treatment time.

  4. Comparison of radiation doses using weight-based protocol and dose modulation techniques for patients undergoing biphasic abdominal computed tomography examinations

    Directory of Open Access Journals (Sweden)

    Livingstone Roshan

    2009-01-01

    Full Text Available Computed tomography (CT of the abdomen contributes a substantial amount of man-made radiation dose to patients and use of this modality is on the increase. This study intends to compare radiation dose and image quality using dose modulation techniques and weight- based protocol exposure parameters for biphasic abdominal CT. Using a six-slice CT scanner, a prospective study of 426 patients who underwent abdominal CT examinations was performed. Constant tube potentials of 90 kV and 120 kV were used for all arterial and portal venous phase respectively. The tube current-time product for weight-based protocol was optimized according to patient′s body weight; this was automatically selected in dose modulations. The effective dose using weight-based protocol, angular and z-axis dose modulation was 11.3 mSv, 9.5 mSv and 8.2 mSv respectively for the patient′s body weight ranging from 40 to 60 kg. For patients of body weights ranging 60 to 80 kg, the effective doses were 13.2 mSv, 11.2 mSv and 10.6 mSv respectively. The use of dose modulation technique resulted in a reduction of 16 to 28% in radiation dose with acceptable diagnostic accuracy in comparison to the use of weight-based protocol settings.

  5. Natural background radiation and population dose in China

    Energy Technology Data Exchange (ETDEWEB)

    Guangzhi, C. (Ministry of Public Health, Beijing, BJ (China)); Ziqiang, P.; Zhenyum, H.; Yin, Y.; Mingqiang, G.

    On the basis of analyzing the data for the natural background radiation level in China, the typical values for indoor and outdoor terrestrial gamma radiation and effective dose equivalents from radon and thoron daughters are recommended. The annual effective dose equivalent from natural radiation to the inhabitant is estimated to be 2.3 mSv, in which 0.54 mSv is from terrestrial gamma radiation and about 0,8 mSv is from radon and its short-lived daughters. 55 Refs.

  6. Regulatory aspects of radiation protection in Indian nuclear plants

    International Nuclear Information System (INIS)

    Chander, Vipin; Pawar, S.K.; Duraisamy, S.

    2012-01-01

    Atomic Energy Act of 1962 covers the radiation safety aspects in the development, control and use of atomic energy. To carry out certain regulatory and safety functions under this act, Atomic Energy Regulatory Board (AERB) was constituted in November 15, 1983. Operating Nuclear Power Plants (NPPs) account for about 60% of occupational collective dose and about 65% of the number of radiation workers in the nuclear fuel cycle facilities. Therefore radiation protection aspects in NPPs are of prime importance. In 1970s and 1980s the high radiation exposures in NPPs was an issue with TAPS-1 and 2 reaching annual collective dose of 50 Person-Sv. In response to this, AERB constituted an expert committee to investigate the possibility of reducing collective doses in NPPs in 1988. Subsequently the recommendations of this committee were implemented in all NPPs. In 1990, International Commission on Radiological Protection (ICRP) recommended a downward revision of occupational dose limit to 20 mSv/yr from the earlier limit of 50 mSv/yr. Regulatory body endorsed these recommendations and gradually brought down the annual dose limits from 40 mSv in 1991 to 30 mSv in 1994 with the limit of 100 mSv averaged over a five year period in line with ICRP recommendations. Over the years, the regulatory body has put in place a sound regulatory frame work and mechanism to ensure adequate protection of occupational workers, members of public and environment due to operation of NPPs. Vast experiences in the field of radiation protection vis-à-vis stringent regulatory requirements such as review of exposure cases and special regulatory inspections during Biennial Shut Down (BSD) has helped in downward trends in occupational and public doses. This paper highlights the role of regulatory body in controlling the radiation doses to both occupational workers and members of public in the NPPs through a three-tier review system. The regulatory oversight, inspections and reviews has resulted in

  7. Radiation practices 1997

    International Nuclear Information System (INIS)

    Havukainen, R.

    1998-05-01

    At the end of 1997, there were 1,753 valid safety licenses in Finland for the use of radiation. In addition, there were 2,065 responsible parties for dental x-ray diagnostics. The registry of STUK - Radiation and Nuclear Safety Authority listed 13,839 radiation sources and 302 radionuclide laboratories. The import of radioactive substances amounted to 1.09 x 10 +16 Bq and export to 2.4 x 10 +13 Bq. Short-lived radionuclides produced in Finland amounted to 5.2 x 10 +13 Bq. There were 11,773 workers monitored for radiation exposure at 1,316 work sites. Of these employees, 24% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of the individual dosemeter readings) was 6.6 Sv in 1997, with nuclear power plant workers accounting for 62% of this total. The annual dosemeter reading of thirteen medical doctors (radiologists, interventional radiologists and cardiologists) and six nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of the dosemeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 253 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations in which unusually high exposure to radiation was an unavoidable part of the task. Reports were made of four incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Two of these cases occurred in the medical use of radiation, one in the use of radiation sources in industry, and one in the use of solarium appliances. (orig.)

  8. Radiation practices 1997

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.

    1998-05-01

    At the end of 1997, there were 1,753 valid safety licenses in Finland for the use of radiation. In addition, there were 2,065 responsible parties for dental x-ray diagnostics. The registry of STUK - Radiation and Nuclear Safety Authority listed 13,839 radiation sources and 302 radionuclide laboratories. The import of radioactive substances amounted to 1.09 x 10{sup +16} Bq and export to 2.4 x 10{sup +13} Bq. Short-lived radionuclides produced in Finland amounted to 5.2 x 10{sup +13} Bq. There were 11,773 workers monitored for radiation exposure at 1,316 work sites. Of these employees, 24% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of the individual dosemeter readings) was 6.6 Sv in 1997, with nuclear power plant workers accounting for 62% of this total. The annual dosemeter reading of thirteen medical doctors (radiologists, interventional radiologists and cardiologists) and six nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of the dosemeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 253 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations in which unusually high exposure to radiation was an unavoidable part of the task. Reports were made of four incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Two of these cases occurred in the medical use of radiation, one in the use of radiation sources in industry, and one in the use of solarium appliances. (orig.)

  9. Radiation exposure dose on persons engaged in radiation-related industries in Korea

    International Nuclear Information System (INIS)

    Lim, Bong Sik

    2006-01-01

    This study investigated the status of radiation exposure doses since the establishment of the 'Regulations on Safety Management of Diagnostic Radiation Generation Device' in January 6, 1995. The level of radiation exposure in people engaged or having been engaged in radiation-related industries of inspection organizations, educational organization, military units, hospitals, public health centers, businesses, research organizations or clinics over a 5 year period from Jan. 1, 2000 to Dec. 31, 2004 was measured. The 149,205 measurement data of 57,136 workers registered in a measurement organization were analysed in this study. Frequency analysis, a Chi-square test, Chi-square trend test, and ANOVA was used for data analysis. Among 57,136 men were 40,870 (71.5%). 50.3% of them were radiologic technologists, otherwise medical doctors (22.7%), nurse (2.9%) and others (24.1%). The average of depth radiation and surface radiation during the 5-year period were found to decrease each year. Both the depth radiation and surface radiation exposure were significantly higher in males, in older age groups, in radiological technologists of occupation. The departments of nuclear medicine had the highest exposure of both depth and surface radiation of the divisions of labor. There were 1.98 and 2.57 per 1,000 person-year were exposed more than 20 mSv (limit recommended by International Commission on Radiological Protection) in depth and surface radiation consequently. The total exposure per worker was significantly decreased by year. But Careful awareness is needed for the workers who exposed over 20 mSv per year. In order to minimize exposure to radiation, each person engaged in a radiation-related industry must adhere to the individual safety management guidelines more thoroughly. In addition, systematic education and continuous guidance aimed at increasing the awareness of safety must be provided

  10. Protection against ionizing radiation by leaded glass googles during interventional cardiology

    International Nuclear Information System (INIS)

    Zett-Lobos, Claudio; Vera Munoz, Felipe; Arriola Alvarez, Katerina; Diaz Ramos, Oscar; Gamarra, Jorge; Fernandez Palomo, Cristian; Merello, Lorenzo; Mora D, Alex; Gutierrez, Alejandro; Catalan Reyes, Monica; Ramos Avasola, Sergio

    2013-01-01

    Background: It is not known whether leaded glass goggles with 0.25 mm Pb equivalency, used in interventional cardiology procedures, attenuate radiation below the levels established by the latest recommendation of the International Commission on Radiological Protection (ICRP). Aim: To assess if the degree of attenuation of the secondary ionizing radiation achieved by the use of 0.25 mm Pb leaded glass goggles, in occupationally exposed workers in interventional cardiology procedures, meets the latest ICRP recommendations. Material and Methods : A prospective investigation was carried out to compare the eye exposure to secondary ionizing radiation received by occupationally exposed personnel in a 9 months period. A set of two thermo luminescent dosimeters was arranged in the front and back of leaded glass goggles in a cohort of seven members of an interventional cardiology service, exposed to 1057 consecutive procedures. Results:The monthly dose equivalent measurement performed in front of the goggles ranged between 1.1 and 6.5 mSv,for paramedics and interventional cardiologists. The radiation measured in the back of the glass varied between 0.66 and 2.75 mSv,respectively.The degree of attenuation of the dose at eye level ranged from 40% to 57.7%,respectively. The projected annual exposure would reach 33 mSv for the interventional cardiologist. Conclusions: With a similar load of work and wearing 0.25 mm Pb equivalent glass goggles, interventional cardiologists will exceed the crystalline equivalent dose limit recommended by the ICRP (20 mSv/year averaged over the past 5 years)

  11. Radiation inactivation of microorganisms on food materials with different dry conditions

    International Nuclear Information System (INIS)

    Ryomoto, Yasuhisa; Ito, Hitoshi

    2001-01-01

    The effect of dry condition of food materials such as spices or herbs with grain or powder were investigated for inactivation of microorganisms by gamma-rays or electron-beams. Radiation sensitivities on endospores of Bacillus pumilus and B. cereus at polished rice, whole black pepper and glass fiber filter dried with additives of 2% peptone + 1% glycerin were almost equivalent, and D 10 values of gamma-rays were obtained to be 1.8 - 2.2 kGy for B. pumilus and 1.2 - 1.3 kGy for B. cereus, respectively. However, D 10 value was decreased to 1.6 kGy for B. pumilus and 1.0 kGy for B. cereus in white pepper powder, and increased significantly as 2.6 kGy for B. pumilus and 1.8 kGy for B. cereus in senna herb powder. In the case of B. megaterium, Enterobacter cloacae and Escherichia coli, D 10 values were increased at all of food materials even in white pepper powder compared with glass fiber filter with additives. These results are indicating that glycerin and related radical scavengers in food components protect the bacteria such as B. megaterium, Ent. cloacae and E. coli more significantly from effects of radiation than B. pumilus or B. cereus. The increase of radiation resistance of these bacteria should be responsible also to the amount of oxygen penetration in bacterial cells which dried at different conditions. On the irradiation of electron-beams, radiation resistance of all of bacteria increased more significantly than gamma-rays which depending to dose rate effects on bacteria. However, increase of radiation resistance was not observed at Aspergillus oryzae in all of food materials at different dry conditions. (author)

  12. Radiation inactivation of microorganisms on food materials with different dry conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ryomoto, Yasuhisa; Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-09-01

    The effect of dry condition of food materials such as spices or herbs with grain or powder were investigated for inactivation of microorganisms by gamma-rays or electron-beams. Radiation sensitivities on endospores of Bacillus pumilus and B. cereus at polished rice, whole black pepper and glass fiber filter dried with additives of 2% peptone + 1% glycerin were almost equivalent, and D{sub 10} values of gamma-rays were obtained to be 1.8 - 2.2 kGy for B. pumilus and 1.2 - 1.3 kGy for B. cereus, respectively. However, D{sub 10} value was decreased to 1.6 kGy for B. pumilus and 1.0 kGy for B. cereus in white pepper powder, and increased significantly as 2.6 kGy for B. pumilus and 1.8 kGy for B. cereus in senna herb powder. In the case of B. megaterium, Enterobacter cloacae and Escherichia coli, D{sub 10} values were increased at all of food materials even in white pepper powder compared with glass fiber filter with additives. These results are indicating that glycerin and related radical scavengers in food components protect the bacteria such as B. megaterium, Ent. cloacae and E. coli more significantly from effects of radiation than B. pumilus or B. cereus. The increase of radiation resistance of these bacteria should be responsible also to the amount of oxygen penetration in bacterial cells which dried at different conditions. On the irradiation of electron-beams, radiation resistance of all of bacteria increased more significantly than gamma-rays which depending to dose rate effects on bacteria. However, increase of radiation resistance was not observed at Aspergillus oryzae in all of food materials at different dry conditions. (author)

  13. Comparative human cellular radiosensitivity: Pt. 1

    International Nuclear Information System (INIS)

    Arlett, C.F.; Green, M.H.L.; Priestley, A.; Harcourt, S.A.; Mayne, L.V.

    1988-01-01

    The authors compared cell killing following 60 Co gamma irradiation in 22 primary human fibroblast strains, nine SV40-immortalized human fibroblast lines and seven SV40-transformed pre-crisis human fibroblast cultures from normal individuals, from ataxia-telangiectasia (A-T) patients and from A-T heterozygotes. They confirmed the greater sensitivity of A-T derived cells to gamma radiation. The distinction between A-T and normal cells is maintained in cells immortalized by SV40-virus but immortal cells are more gamma radiation resistant than corresponding primary fibroblasts. Cells transformed by plasmids (pSV3gpt and pSV3neo) expressing SV40 T-antigen, both pre- and post-crisis, show this increased resistance, indicating that expression of SV40 T-antigen, rather than immortalization per se is responsible for the change. (author)

  14. Assessment of external and internal doses due to farming in high background radiation areas in old tin mining localities in Jos-plateau, Nigeria

    International Nuclear Information System (INIS)

    Jibiri, N.N.; Farai, I.P.; Alausa, S.K.

    2009-01-01

    Farming on soils situated in high background radiation areas can result to enhanced radiation exposure scenarios and pathways to humans. To assess the likely levels of exposures, farm soil samples were collected from different farmlands in three old tin mining localities (Bitsichi, Bukuru and Ropp) in Jos Plateau Nigeria, known for high radiations. The soil samples were analyzed for the activity concentrations of 226 Ra, 232 Th and 40 K, using gamma-ray spectroscopy. The outdoor annual effective dose rates were calculated using the activity concentrations of the radionuclides and were found to vary from 0.07 mSv to 2.02 mSv across the three localities. Considering dust generation from soil tillage and inadvertent ingestion of soil particles, the likely internal radiation hazards were estimated using conservative dust and soil loading factors. The total average annual effective dose rates due to 226 Ra and 232 Th that could result from dust inhalation and ingestion of soil particles were 16.9 μSv, 8.1 μSv and 8.8 μSv, respectively for Bitsichi, Bukuru and Ropp. Though these values are about 5% the outdoor exposures to the farmers in those farms and greater than 1 μSv y-1, from the point of view of radiation protection and risk, they are significant. It suffices to say, therefore, that the results of this study will create the possibility of the importance to evaluate the health risk among the farming population and workplace environments which often is not covered by regulations concerning health protection. (author)

  15. Potassium-40 content in male radiation workers at Narora Atomic Power Station

    International Nuclear Information System (INIS)

    Kumar, M.; Sharma, L.N.

    2001-01-01

    749 radiation workers at NAPS, aged 20 to 59 years, were monitored by using Shadow Shield Whole Body Counting System, having NaI (Tl) crystal coupled with 4K Multi Channel Analyser (MCA), to determine the 40 K activity in the body and assess internal dose due to naturally occurring 40 K. These subjects belonged to 18 different states with nearly 54% from Uttar Pradesh. The data have been grouped for analysis in vegetarian and non-vegetarian. The paper describes the calibration details of whole body counter for 40 K using water phantom. The frequency distribution of natural potassium content (g K kg -1 body weight) is found to be normally distributed with the peak occurring for 1.70-1.90g K kg -1 grouping. The average natural potassium content per unit body weight (g K kg -1 ) (average 40 K activity kBq kg -1 ) for vegetarian, non-vegetarian and all subjects taken together is found to be 1.84 (57.66), 1.92 (60.20) and 1.88(58.86) respectively. The data obtained could be expressed as a linear relationship C= A+Bx, where 'C' is the potassium content per unit body weight in g K kg - 1 o f body weight and 'x' is the age of the subject, in years. The coefficient A and B for vegetarian, non-vegetarian and all subjects taken together are found to be 1.89 and -0.002, 2.18 and -0.008 and 2.03 and -0.005 respectively. The data obtained for all these groups was also fitted in a linear relationship between the activity due to 40 K(kBq) and the ratio of weight to height, W/H (kg cm - 1 ) . The average annual dose from 40 K for the subjects is evaluated as 165.42±37.91μSv. (author)

  16. Radiation inactivation analysis of chloroplast CF0-CF1 ATPase

    International Nuclear Information System (INIS)

    Wang, M.Y.; Chien, L.F.; Pan, R.L.

    1988-01-01

    Radiation inactivation technique was employed to measure the functional size of adenosine triphosphatase of spinach chloroplasts. The functional size for acid-base-induced ATP synthesis was 450 +/- 24 kilodaltons; for phenazine methosulfate-mediated ATP synthesis, 613 +/- 33 kilodaltons; and for methanol-activated ATP hydrolysis, 280 +/- 14 kilodaltons. The difference (170 +/- 57 kilodaltons) between 450 +/- 24 and 280 +/- 14 kilodaltons is explained to be the molecular mass of proton channel (coupling factor 0) across the thylakoid membrane. Our data suggest that the stoichiometry of subunits I, II, and III of coupling factor 0 is 1:2:15. Ca2+- and Mg2+-ATPase activated by methanol, heat, and trypsin digestion have a similar functional size. However, anions such as SO 3 (2-) and CO 3 (2-) increased the molecular mass for both ATPase's (except trypsin-activated Mg2+-ATPase) by 12-30%. Soluble coupling factor 1 has a larger target size than that of membrane-bound. This is interpreted as the cold effect during irradiation

  17. Immune cells in Chernobyl recovery operation workers exposed over 500 mSv

    International Nuclear Information System (INIS)

    Bazyka, D.; Byelyaeva, N.; Chumak, A.; Golyarnik, N.; Maznichenko, O.; Kovalenko, Ju.

    2004-01-01

    Immune response parameters were studied in Chernobyl radiation emergency workers exposed to radiation over 500 mSv during 1986. Initial response stage to the radiation exposure was characterised by immunological deficiency with T-cell subsets changes. In the reconstitution period inhibition of immune function was associated with lymphocyte subset changes such as decreased CD3 + and CD4 + cell counts and increased number of somatic mutations in TCR-locus. Late period after the acute radiation exposure in Chernobyl radiation emergency workers is characterized by decreased CD8 + suppressor cell function that could lead to poor proliferation control. Subset analysis of CD34 + cells showed in ARS survivors counts significantly higher than in control especially for the most primitive progenitors with CD34 + CD90 + CD45 -/l ow and CD34 + CD45 - CD38 - phenotypes. (author)

  18. Repeated Administration of D-Amphetamine Induces Distinct Alterations in Behavior and Metabolite Levels in 129Sv and Bl6 Mouse Strains

    Directory of Open Access Journals (Sweden)

    Taavi Vanaveski

    2018-06-01

    Full Text Available The main goal of the study was to characterize the behavioral and metabolomic profiles of repeated administration (for 11 days of d-amphetamine (AMPH, 3 mg/kg i. p., indirect agonist of dopamine (DA, in widely used 129S6/SvEvTac (129Sv and C57BL/6NTac (Bl6 mouse strains. Acute administration of AMPH (acute AMPH induced significantly stronger motor stimulation in Bl6. However, repeated administration of AMPH (repeated AMPH caused stronger motor sensitization in 129Sv compared acute AMPH. Body weight of 129Sv was reduced after repeated saline and AMPH, whereas no change occurred in Bl6. In the metabolomic study, acute AMPH induced an elevation of isoleucine and leucine, branched chain amino acids (BCAA, whereas the level of hexoses was reduced in Bl6. Both BCAAs and hexoses remained on level of acute AMPH after repeated AMPH in Bl6. Three biogenic amines [asymmetric dimethylarginine (ADMA, alpha-aminoadipic acid (alpha-AAA, kynurenine] were significantly reduced after repeated AMPH. Acute AMPH caused in 129Sv a significant reduction of valine, lysophosphatidylcholines (lysoPC a C16:0, lysoPC a C18:2, lysoPC a C20:4, phosphatidylcholine (PC diacyls (PC aa C34:2, PC aa C36:2, PC aa C36:3, PC aa C36:4 and alkyl-acyls (PC ae C38:4, PC ae C40:4. However, repeated AMPH increased the levels of valine and isoleucine, long-chain acylcarnitines (C14, C14:1-OH, C16, C18:1, PC diacyls (PC aa C38:4, PC aa C38:6, PC aa C42:6, PC acyl-alkyls (PC ae C38:4, PC ae C40:4, PC ae C40:5, PC ae C40:6, PC ae C42:1, PC ae C42:3 and sphingolipids [SM(OHC22:1, SM C24:0] compared to acute AMPH in 129Sv. Hexoses and kynurenine were reduced after repeated AMPH compared to saline in 129Sv. The established changes probably reflect a shift in energy metabolism toward lipid molecules in 129Sv because of reduced level of hexoses. Pooled data from both strains showed that the elevation of isoleucine and leucine was a prominent biomarker of AMPH-induced behavioral sensitization

  19. Enhanced replication of damaged SV40 DNA in carcinogen-treated monkey cells

    International Nuclear Information System (INIS)

    Maga, J.A.; Dixon, K.

    1984-01-01

    Treatment of mammalian cells with certain chemical or physical carcinogens prior to infection with ultraviolet-irradiated virus results in enhanced survival or reactivation of the damaged virus. To investigate the molecular basis of this enhanced reactivation (ER), Simian virus 40 DNA replication in carcinogen-treated cells was examined. Treatment of monkey kidney cells with N-acetoxy-2-acetylamino-fluorene or UV radiation 24 h prior to infection with ultraviolet-irradiated Simian virus 40 leads to enhancement of viral DNA replication measured at 36 h after infection by [ 3 H]thymidine incorporation or hybridization. The enhancement of DNA replication is observed when cells are treated from 1 to 60 h before infection or 1 to 16 h after infection. The fact that enhancement is observed also when cells are treated after infection rules out the possiblity that enhancement occurs at the level of adsorption or penetration of the virus. Measurements of the time course of viral DNA replication indicate that pretreatment of cells does not alter the time of onset of viral DNA replication. It is concluded that ER of Simain virus 40 occurs at the level of viral DNA replication. (author)

  20. Inactivation of Bacterial Spores and Vegetative Bacterial Cells by Interaction with ZnO-Fe2O3 Nanoparticles and UV Radiation

    Directory of Open Access Journals (Sweden)

    José Luis Sánchez-Salas

    2017-09-01

    Full Text Available ZnO-Fe2O3 nanoparticles (ZnO-Fe NPs were synthesized and characterized by scanning electron microscopy (SEM, energy dispersive X-ray spectroscopy (EDS and dynamic light scattering (DLS. The generation of chemical reactive hydroxyl radicals (•OH was measured spectrophotometrically (UV-Vis by monitoring of p-nitrosodimethylaniline (pNDA bleaching. Inactivation of E. coli and B. subtilis spores in the presence of different concentrations of ZnO-Fe NPs, under UV365nm or visible radiation, was evaluated. We observed the best results under visible light, of which inactivation of E. coli of about 90% was accomplished in 30 minutes, while B. subtilis inactivation close to 90% was achieved in 120 minutes. These results indicate that the prepared photocatalytic systems are promising for improving water quality by reducing the viability of water-borne microorganisms, including bacterial spores.

  1. Study of the natural radiation background affected on the human body in some areas of Viet Nam

    International Nuclear Information System (INIS)

    Ngo Van Thanh

    2008-01-01

    The author had studied the natural radiation background in 68 districts belong 40 provinces and cities of Vietnam from 2002 to 2005. The estimated results clearly show that the average external irradiation dose levels and the average annual external radiation equivalent dose affected on the human body are 0.181± 0.0189 μSv/h and 1599 ± 171.8 μSv/year respectively, both are in normal limit; the highest levels are in Lai Chau district (Lai Chau province); the lowest levels are in Buon Ma Thuot city (DakLak province), Phuoc Son district (Quang Nam province), Tan An district (Long An province). The radon concentration in the human being and the average annual internal inhalation irradiation equivalent dose affected on the human beings are 26.9 ± 15.89 Bq/m 3 and 392.88 ± 231.99 μSv/year respectively; the maximums are in Nha Trang city (Khanh Hoa province), Bac Binh district (Binh Phuoc province); the minimums are in Vung Tau city (Ba Ria- Vung Tau province), Tan An district (Long An province), Rach Gia district (Kien Giang province). The terrestrial radionuclide concentrations in the cereals, foodstuffs (rice, meat, vegetables), water, earth and the average annual internal irradiation equivalent dose are 829.2 ± 38.06 Bq/kg and 229.3 ± 67.70 μSv/year respectively; the highest levels are in Phong Tho district (Lai Chau province), Dien Bien city; the lowest levels are in Dong Xoai district (Binh Phuoc province), Tan An district (Long An province). The average total annual natural radiation background effective equivalent dose level affected on the human body is 2206.9 ± 529.30 μSv/year; the highest levels are in Lai Chau district (Lai Chau province); the lowest levels are in Tan An district (Long An province). The 14 maps of Natural Radiation Background in several localized regions belong 40 provinces and cities of Viet Nam had been set up. These results can reserve for serviceman and public health in the both wartime and peacetime. (author)

  2. Radiation doses during chest examinations using dose modulation techniques in multislice CT scanner

    International Nuclear Information System (INIS)

    Livingstone, Roshan S.; Pradip, Joe; Dinakran, Paul M.; Srikanth, B.

    2010-01-01

    Objectives: To evaluate the radiation dose and image quality using a manual protocol and dose modulation techniques in a 6-slice CT scanner. Materials and Methods: Two hundred and twenty-one patients who underwent contrast-enhanced CT of the chest were included in the study. For the manual protocol settings, constant tube potential (kV) and tube current-time product (mAs) of 140 kV and 120 mAs, respectively, were used. The angular and z-axis dose modulation techniques utilized a constant tube potential of 140 kV; mAs values were automatically selected by the machine. Effective doses were calculated using dose-length product (DLP) values and the image quality was assessed using the signal-to-noise (SNR) ratio values. Mean effective doses using manual protocol for patients of weights 40-60 kg, 61-80 kg, and 81 kg and above were 8.58 mSv, 8.54 mSv, and 9.07 mSv, respectively. Mean effective doses using z-axis dose modulation for patients of weights 40-60 kg, 61-80 kg, and 81 kg and above were 4.95 mSv, 6.87 mSv, and 10.24 mSv, respectively. The SNR at the region of the liver for patients of body weight of 40-60 kg was 5.1 H, 6.2 H, and 8.8 H for manual, angular, and z-axis dose modulation, respectively. Conclusion: Dose reduction of up to 15% was achieved using angular dose modulation and of up to 42% using z-axis dose modulation, with acceptable diagnostic image quality compared to the manual protocol. (author)

  3. Task-specific monitoring of nuclear medicine technologists' radiation exposure

    International Nuclear Information System (INIS)

    Smart, R.

    2004-01-01

    Many studies have demonstrated that the exposure of nuclear medicine technologists arises primarily from radioactive patients rather than from preparation of radiopharmaceuticals. However, in order to devise strategies to reduce staff exposure, it is necessary to identify the specific tasks within each procedure that result in the highest radiation doses. An ESM Eberline FH41B-10 radiation dosemeter, which records the ambient dose equivalent rate, was used to monitor the radiation exposure of a technologist and to record the dose rate in μSv per hour every 32 s throughout a working day. The technologist recorded the procedures that were being performed so that the procedures that resulted in higher doses could be identified clearly. The measured doses clearly showed that the major contributions to the technologist's dose were the following: (1) transferring incapacitated patients from the imaging table to a hospital trolley; (2) difficult injections without syringe shields; and (3) setting up patients for gated myocardial scans. The average dose to the technologist from transferring patients after a bone scan was 0.54 μSv, 40% of the total dose of 1.3 μSv for the complete bone scan procedure. The average dose received injecting 900 MBq of 99 Tc m -HDP using a tungsten syringe shield was 0.57 μSv, but the highest dose was 1.6 μSv, in a patient in whom the injection was difficult. A 0.5 mm lead apron was found to reduce the dose when setting up a patient for a gated stress 99 Tc m -sestamibi myocardial scan by approximately a factor of 2. The average dose per patient for this task was reduced from 1.1 to 0.6 μSv. It is recommended that staff waiting for assistance with patient transfers stand away from the patient, that tungsten syringe shields be used for all radiopharmaceutical injections and that a 0.5 mm lead apron be worn when attending patients containing high activities of 99 Tc m radiopharmaceuticals, such as those having myocardial imaging. (authors)

  4. Exposure to the ionizing radiation in Poland in 2001

    International Nuclear Information System (INIS)

    Henschke, J.; Biernacka, M.; Florowska, K.; Sosinska, A.

    2002-01-01

    The population of Poland is at present subject to ionizing radiation from natural and artificial sources at levels not much different from those in other European countries. Natural sources of radiation such as cosmic rays, terrestrial radiation, radon gas in homes and other natural radionuclides entering human body with air, water and food contributed ca. 2.5 mSv to the total annual radiation dose of 3.36 mSv received in 2001 by average inhabitant of our country. The irradiation from artificial sources, such as X-ray machines, cyclotrons and radionuclides used in medical diagnostics and in industry and science, the fallout from nuclear explosions and from the Chernobyl accident, now contribute 0.87 mSv, or about 36% to the total radiation dose; most of the men-made dose is from medical irradiation which contributes 0.85 mSv, or ca. 25% to the total dose. The Chernobyl fallout is now responsible for only 0.012 mSv per year, or 0.4% of the total radiation dose received currently by the Polish population. (author)

  5. Radiation risks in the 20. Century: reality, illusions and ethics

    International Nuclear Information System (INIS)

    Jaworowski, Z.

    1998-01-01

    Average global natural ionizing radiation dose for man is 2.4 mSv/year ranging in various geographical regions from about 1 to 220 mSv/year. At the dawn of life this dose was by a factor of three to five higher than now. The entire man-made contribution to radiation dose is only about 0.2% of natural radiation. From medical radiodiagnostics the average global dose is about 0.5 mSv/year, from nuclear explosions was in 1963 <0.2 mSv/year, from Chernobyl accident was in 1986-1987 0.05 mSv/year, and from nuclear power in 1995 about 0.007 mSv/year. Radiation is rather a weak noxious agent as compared with other natural and man-made hazards. Radiophobia has its source not in real peace-time radiation hazard to population, but in politics and group interests. Current excessive radiation protection standards, e.g. 1mSv/year, are based on an arbitrary assumption on linearity and a lack of threshold in dose/effect relationship, and on ignoring the beneficial effects of low doses of radiation. A whole body dose rate of 1mSv/year causes about 2 DNA damages in each cell. This can be compared with 70 million natural DNA damaging events occurring in each cell per year. Regulations based on this assumption lead to the wasting of resources desperately needed to deal with real health problems, and to strangulation of development of environmentally and human friendly nuclear technologies. Radiation standards should be based on 'practical threshold', one below which induction of detectable radiogenic cancers or genetic effects is not expected. (author)

  6. Simian virus 40 infection in humans and association with human diseases: results and hypotheses

    International Nuclear Information System (INIS)

    Barbanti-Brodano, Giuseppe; Sabbioni, Silvia; Martini, Fernanda; Negrini, Massimo; Corallini, Alfredo; Tognon, Mauro

    2004-01-01

    Simian virus 40 (SV40) is a monkey virus that was introduced in the human population by contaminated poliovaccines, produced in SV40-infected monkey cells, between 1955 and 1963. Epidemiological evidence now suggests that SV40 may be contagiously transmitted in humans by horizontal infection, independent of the earlier administration of SV40-contaminated poliovaccines. This evidence includes detection of SV40 DNA sequences in human tissues and of SV40 antibodies in human sera, as well as rescue of infectious SV40 from a human tumor. Detection of SV40 DNA sequences in blood and sperm and of SV40 virions in sewage points to the hematic, sexual, and orofecal routes as means of virus transmission in humans. The site of latent infection in humans is not known, but the presence of SV40 in urine suggests the kidney as a possible site of latency, as it occurs in the natural monkey host. SV40 in humans is associated with inflammatory kidney diseases and with specific tumor types: mesothelioma, lymphoma, brain, and bone. These human tumors correspond to the neoplasms that are induced by SV40 experimental inoculation in rodents and by generation of transgenic mice with the SV40 early region gene directed by its own early promoter-enhancer. The mechanisms of SV40 tumorigenesis in humans are related to the properties of the two viral oncoproteins, the large T antigen (Tag) and the small t antigen (tag). Tag acts mainly by blocking the functions of p53 and RB tumor suppressor proteins, as well as by inducing chromosomal aberrations in the host cell. These chromosome alterations may hit genes important in oncogenesis and generate genetic instability in tumor cells. The clastogenic activity of Tag, which fixes the chromosome damage in the infected cells, may explain the low viral load in SV40-positive human tumors and the observation that Tag is expressed only in a fraction of tumor cells. 'Hit and run' seems the most plausible mechanism to support this situation. The small tag

  7. On the risk to low doses (<100 mSv) of ionizing radiation during medical imaging procedures - IOMP policy statement

    International Nuclear Information System (INIS)

    Pradhan, A.S.

    2013-01-01

    The science committee of International Organization for Medical Physics (IOMP) developed a policy statement on the predictions of radiation-induced cancers and cancer deaths in patients exposed to low doses (<100 mSv) of ionizing radiation during medical imaging; this statement has been approved by the IOMP council. In order to attract the attention of medical physicists, an editorial (1) titled 'Risk of Medical Imaging' that includes the said statement has recently been published in Medical Physics journal of American Association of Physicists in Medicine (AAPM). As stated, IOMP represents 80 national and 6 regional medical physics organizations and 18,000 medical physicists worldwide. The IOMP affiliated bodies/organizations in different countries (such as Association of Medical Physicists of India, AMPI) have been encouraged to reproduce the IOMP statement in their journals/newsletters for the benefit of larger community of medical physicists. The IOMP statement is reproduced below (readers may also go through the supportive literature listed in references). It is hoped that this policy statement will have some deterrent influence on the continued propagation of unproven risk related to medical imaging procedures conducted with small doses.

  8. Radiation survey of aircraft and heavy machinery scrap.

    Science.gov (United States)

    Idriss, Hajo; Salih, Isam; Gumaa, Elsadig; Yassin, Abbas; Yousif, E H; Abdel Hamid, Saad Eldeen M; Sam, A K

    2012-12-01

    This study was conducted primarily to survey aircraft and heavy machinery at 30 locations within Khartoum State using handheld radiation survey meters to detect and identify any radiation sources that might be present and to estimate radiation dose levels. The survey has resulted in detection of 16 sealed sources of (90)Sr and one of (226)Ra in aircraft scrap. Of course, (90)Sr sources are used in military aircraft as temperature sensors while (226)Ra is used for indicating fuel levels. These sources were found intact without spreading radioactivity contamination; however, none was detected in heavy machine scrap. The levels of radiation dose measured at 0.1m from the source fall within the range of 25.1-40.2 μSv/h with an average value of 33.52 ± 4.06 μSv/h. These orphan sources have been separated from the scrap, tested for possible leakage, conditioned and stored in waste management facility. The result of this study has revealed without doubt that the scrap constitute a serious source of public exposure and highlights the importance of legislation making radiation monitoring of scrap in the country mandatory before it is sold to metal industry for reprocessing. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. p53-stabilizing Agent CP-31398 Prevents Growth and Invasion of Urothelial Cancer of the Bladder in Transgenic UPII-SV40T Mice

    Directory of Open Access Journals (Sweden)

    Venkateshwar Madka

    2013-08-01

    Full Text Available The high prevalence of bladder cancer and its recurrence make it an important target for chemoprevention. About half of invasive urothelial tumors have mutations in p53. We determined the chemopreventive efficacy of a p53-stabilizing agent, CP-31398, in a transgenic UPII-SV40T mouse model of bladder transitional cell carcinoma (TCC that strongly resembles human TCC. After genotyping, six-week-old UPII-SV40T mice (n = 30/group were fed control (AIN-76A or experimental diets containing 150 or 300 ppm of CP-31398 for 34 weeks. Progression of bladder cancer growth was monitored by magnetic resonance imaging. At 40 weeks of age, all mice were killed; urinary bladders were collected to determine weights, tumor incidence, and histopathology. There was a significant increase in bladder weights of transgenic versus wild-type mice (male: 140.2 mg vs 27.3 mg, P < .0001; female: 34.2 mg vs 14.8 mg, P < .0001. A significant decrease in the bladder tumor weights (by 68.6–80.2%, P < .0001 in males and by 36.9–55.3%, P < .0001 in females was observed in CP-31398-treated mice. Invasive papillary TCC incidence was 100% in transgenic mice fed control diet. Both male and female mice exposed to CP-31398 showed inhibition of invasive TCC. CP-31398 (300 ppm completely blocked invasion in female mice. Molecular analysis of the bladder tumors showed an increase in apoptosis markers (p53, p21, Bax, and Annexin V with a decrease in vascular endothelial growth factor in transgenic mice fed CP-31398. These results suggest that p53-modulating agents can serve as potential chemopreventive agents for bladder TCC.

  10. Estimation of natural radiation background level and population dose in China

    International Nuclear Information System (INIS)

    Pan Ziqiang

    1992-01-01

    The authors describe in general the natural radiation background level in China, and based on available data present an estimated annual effective dose equivalent of the population to natural radiation that is some 2.3 mSv, of which about 0.54 mSv is from original γ radiation and about 0.8 mSv from radon and its short-lived daughters

  11. The space radiation environment

    International Nuclear Information System (INIS)

    Robbins, D.E.

    1997-01-01

    There are three primary sources of space radiation: galactic cosmic rays (GCR), trapped belt radiation, and solar particle events (SPE). All are composed of ions, the nuclei of atoms. Their energies range from a few MeV u -1 to over a GeV u -1 . These ions can fragment when they interact with spacecraft materials and produce energetic neutrons and ions of lower atomic mass. Absorbed dose rates inside a typical spacecraft (like the Space Shuttle) in a low inclination (28.5 degrees) orbit range between 0.05 and 2 mGy d -1 depending on the altitude and flight inclination (angle of orbit with the equator). The quality factor of radiation in orbit depends on the relative contributions of trapped belt radiation and GCR, and the dose rate varies both with orbital altitude and inclination. The corresponding equivalent dose rate ranges between 0.1 and 4 mSv d -1 . In high inclination orbits, like that of the Mir Space Station and as is planned for the International Space Station, blood-forming organ (BFO) equivalent dose rates as high as 1.5 mSv d -1 . Thus, on a 1 y mission, a crew member could obtain a total dose of 0.55 Sv. Maximum equivalent dose rates measured in high altitude passes through the South Atlantic Anomaly (SAA) were 10 mSv h -1 . For an interplanetary space mission (e.g., to Mars) annual doses from GCR alone range between 150 mSv y -1 at solar maximum and 580 mSv y -1 at solar minimum. Large SPE, like the October 1989 series, are more apt to occur in the years around solar maximum. In free space, such an event could contribute another 300 mSv, assuming that a warning system and safe haven can be effectively used with operational procedures to minimize crew exposures. Thus, the total dose for a 3 y mission to Mars could exceed 2 Sv

  12. Radiation exposure to nuclear medicine technologists from administering I-131 therapy dosages

    International Nuclear Information System (INIS)

    Chaudakshetrin, P.; Pusuwan, P.; Sritongkul, N.; Tuntawiroon, M.

    2007-01-01

    Full text: Therapeutic doses of I-131 for treatment of thyroid cancer are administered orally in liquid or capsule form. During the last few years, a total number of patients loaded in our isolation ward increased from 4 to 10 patients per week. When considering radiation safety precautions for attending technologists, it is preferable to use the dose in capsules. The purpose of this study is to compare radiation exposure to nuclear medicine technologists from administering I-131 therapy dosages in capsules and in liquid form in a closed system. Materials and Methods: Three year radiation exposure to technologists during I-131 administration was analyzed. From January 2004 to June 2005 dose administration was in liquid form (n=263) and from July 2005 to February 2007 in capsules (n=541). Radiation dose assessment was performed with an electronic personal dosimeter (PDM 112). The dose rate in μSv and time spent per patient were recorded. Results: Dose received per patient when I-131 was given in a liquid was 3.50 ± 1.67 μSv and 1.17 ± 0.66 μSv when given in capsules. Compared with the use of a liquid, capsules significantly reduced radiation dose to technologists by 66% (P < 0.001). These doses received depended not only on the administered activity but also on the time, distance and shielding. Time spent per patient, including a brief visit before the time of dosing to explain the procedure and answer questions was reduced slightly from 4.4 ± 2.2 to 3.7 ± 1.8 minutes (P < 0.01). These correspond to a reduction in a yearly dose to 1 technologist by 40%, from 0.63 mSv to 0.38 mSv from dosing to 175 and 325 patients respectively. Conclusions: The measured doses clearly showed that handling of I-131 therapy dosages either in a liquid form or capsules are not the major contributors to the technologist's radiation exposure in routine clinical practice. However, one has to be cautious and follow good work practice to avoid risk of radiation exposure and radioiodine

  13. Use of radiation and radiation practices in 1993. Events and statistics

    International Nuclear Information System (INIS)

    Havukainen, R.

    1994-05-01

    In the end of the year 1993 there were in force 1740 safety licences for the use of radiation granted by the Finnish Centre for Radiation and Nuclear Safety (STUK). In addition to this there were 2100 places for dental x-ray activities in Finland. All together 12726 radiation sources and 313 radioisotope laboratories were in use. The import of radioactive substances was 3.9 x 10 15 Bq and the export 2.5 x 10 13 Bq. The production of short-lived isotopes was 1.3 x 10 13 Bq. The monitoring of personal radiation doses was organized for 11171 workers and 1299 working places. The annual dose (the integrated readings of dosemeters) was greater than registration threshold for 24% of workers. The collective dose (the sum of the results of the dose measurements) registered to the Finnish Dose Register was 6.9 manSv; 74% belonged to the workers of nuclear power plants. The sum of the personal doses measured in 1993 were for three interventional radiologists and fifteen workers in nuclear power plants 20 mSv or more. The effective doses were in each case under the annual dose limit of 50 mSv. The effective doses for the interventional radiologists were under 20 mSv. (7 figs., 16 tabs.)

  14. Series 'Facing Radiation'. 2 Facing radiation is facing residents

    International Nuclear Information System (INIS)

    Hanzawa, Takahiro

    2013-01-01

    The series is to report how general people, who are not at all radiological experts, have faced and understood the problems and tasks of radiation given by the Fukushima Daiichi Nuclear Power Plant Accident (Mar. 2011). The section 2 is reported by an officer of Date City, which localizes at 60 km northern west of the Plant, borders on Iitate Village of Fukushima prefecture, and is indicated as the important area of contamination search (IACS), which the reporter has been conducted for as responsible personnel. In July 2011, the ambient dose was as high as 3.0-3.5 mc-Sv/h and the tentative storage place of contaminated materials was decided by own initiative of residents of a small community, from which the real decontamination started in the City. The target dose after decontamination was defined to be 1.0 mc-Sv/h: however, 28/32 IACS municipalities in the prefecture had not defined the target although they had worked for 2 years after the Accident for their areas exceeding the standard 0.23 mc-Sv/h. At the moment of decontamination of the reporter's own house, he noticed that resident's concerns had directed toward its work itself, not toward the target dose, and wondered if these figures had obstructed to correctly face the radiation. At present that about 2.5 years have passed since the Accident, all of Date citizens have personal accumulated glass dosimeters for seeing the effective external dose and it seems that their dose will not exceed 1 mSv/y if the ambient dose estimated is 0.3-5 mc-Sv/h. Media run to popularity not to face radiation, experts tend to hesitate to face media and residents, and radiation dose will be hardly reduced to zero, despite that correct understanding of radiation is a shorter way for residents' own ease: facing radiation is facing residents. (T.T.)

  15. Occupational radiation exposure in Korea: 2002

    International Nuclear Information System (INIS)

    Jeong, Je Ho; Kwon, Jeong Wan; Lee, Jai Ki

    2005-01-01

    Dose distribution of Korean radiation workers classified by occupational categories was analyzed. Statistics of the Occupational Radiation Exposure(ORE) in 2002 of the radiation workers in diagnostic and dental radiology were obtained from the Korea Food and Drug Agency(KFDA) who maintains the database for individual radiation dose records. Corresponding statistics for the rest of radiation workers were obtained by processing the individual annual doses provided by the Korea RadioIsotope Association(KRIA) after deletion of individual information. The ORE distribution was classified in term of 28 occupational categories, annual individual dose levels, age groups and gender of 52733 radiation workers as of the year of 2002. The total collective dose was 66.4 man-Sv and resulting average individual ORE was 1.26 mSv. Around 80% of the workers were exposed to minimal doses less than 1.2 mSv. However, it appeared that the recorded doses exceeded 20 mSv for 43 workers in the industrial radiography and for 147 workers in the field of radiology. Particularly, recorded doses of 23 workers in radiology exceeded the annual dose limits of 50 mSv, which is extraordinary when the working environment is considered. It is uncertain whether those doses are real or caused by careless placing of dosimeters in the imaging rooms while the X-ray units are in operation. No one in the workforce of 16 operating nuclear power plant units was exposed over 20 mSv in 2002. Number of workers was the largest in their 30's of age and the mean individual dose was the highest in their 20's. Women were around 20% of the radiation workers and their average dose was around one half of that of man workers

  16. Staff radiation doses during eight years in a nuclear medicine radiopharmacy

    International Nuclear Information System (INIS)

    Jansen, S.E.; Aswegen, A. van; Loetter, M.G.; Herbst, C.P.; Otto, A.C.; Orange Free State Univ., Bloemfontein

    1994-01-01

    Staff working in the radiopharmacy and nursing staff responsible for injecting radionuclides are being monitored constantly in our department. We report here on the effective doses and doses to the hands received by staff at two hospitals during 8 years from January 1985 to December 1992. In addition to the doses determined monthly by the South African Bureau of Standards' Radiation Protection Service (SABS), radiation doses received to the hands and whole body were measured every week using lithium fluoride thermoluminescent dosimetry (TLD). The highest total radiation dose received in any one year by any one person at hospital A was 233.53 mSv to the hands, and 10.20 mSv and 8.37 mSv to the whole body depending on the dosemeter used. The corresponding values for hospital B were 54.05 mSv to the hands and 6.94 mSv and 4.43 mSv to the whole body. If only one radiographer should do all the work calculated highest dose received would be 447.06 mSv to the hands and 9.68 mSv SABS effective dose. The radiation doses to staff were well within the limits prescribed. (Author)

  17. Radiation related cancer risk after ionization radiation exposure to the Bulgarian population

    International Nuclear Information System (INIS)

    Chobanova, N.; Vasilev, G.; Hadjieva, T.

    2008-01-01

    Average annual individual effective dose of natural radiation background (NRB) for the Bulgarian population is estimated to be 2.33 mSv.a -1 (from 1.60 to 3.06). NRB has been considered nearly constant in time, but during the 20th century the radiation above NRB has gradually increased. It was mainly caused by the medical X-ray and radionuclide diagnostics, radiation treatment, occupational radiation, global radioactive fallout, Chernobyl accident, exploitation of thermal power and nuclear power stations, etc. For the years 1950-2000 collective dose from NRB represents 965 000 man.Sv and radiation over NRB gives 1 042 800 man.Sv. Population risk following radiation exposure is estimated mainly on stochastic health effect by implementation of the so-called Linear non-threshold model (LNM) dose-effect. It postulates no dose threshold for radiation-induced health effects. Using different models, assumptions and assessments, authors have determined the contribution of lethal radiogenic cancer to Bulgarian spontaneous cancer rate to be from 3.7% to 20.6%. Numerous contradictions and concepts about the LNM still persist, because from statistical point of view, LNM can neither be proved nor rejected. (authors)

  18. Environmental radioactivity and radiation exposure in Switzerland 1995; Umweltradioaktivitaet und Strahlendosen in der Schweiz 1995

    Energy Technology Data Exchange (ETDEWEB)

    Voelkle, H; Gobet, M

    1997-12-31

    Switzerland has been performing systematic monitoring of radioactivity in the environment and in food for forty years. This report contains the results of measurements made in the course of 1995 and the consequential radiation doses for the population. The monitoring programme deals with radioactivity in the atmosphere, precipitation, aquatic systems, soil, grass, foodstuffs and the human body, but also includes natural radiation, doses due to radon inside dwellings, emissions from nuclear power stations and other operations using radionuclides, as well as miscellaneous radiation sources. All the nuclear power plants and other facilities licensed to handle radioactive substances remained within their annual release limits in 1995, and environmental measurements revealed no inadmissible immission or dose values. The population`s mean annual radiation dose totals 4 mSv, with some 40% of this due to radon in the home (but with extreme values as high as 100 mSv), another 30% coming from natural radiation, a quarter from medical applications and less than 5% from artificial radiation. (author) figs., tabs., refs.

  19. Environmental radioactivity and radiation exposure in Switzerland 1995; Umweltradioaktivitaet und Strahlendosen in der Schweiz 1995

    Energy Technology Data Exchange (ETDEWEB)

    Voelkle, H.; Gobet, M.

    1996-12-31

    Switzerland has been performing systematic monitoring of radioactivity in the environment and in food for forty years. This report contains the results of measurements made in the course of 1995 and the consequential radiation doses for the population. The monitoring programme deals with radioactivity in the atmosphere, precipitation, aquatic systems, soil, grass, foodstuffs and the human body, but also includes natural radiation, doses due to radon inside dwellings, emissions from nuclear power stations and other operations using radionuclides, as well as miscellaneous radiation sources. All the nuclear power plants and other facilities licensed to handle radioactive substances remained within their annual release limits in 1995, and environmental measurements revealed no inadmissible immission or dose values. The population`s mean annual radiation dose totals 4 mSv, with some 40% of this due to radon in the home (but with extreme values as high as 100 mSv), another 30% coming from natural radiation, a quarter from medical applications and less than 5% from artificial radiation. (author) figs., tabs., refs.

  20. Fallout and radiation doses in Norway after the Chernobyl accident

    International Nuclear Information System (INIS)

    Henriksen, T.

    1987-08-01

    Due to southeasterly wind and rainfall during the critical days after the Chernobyl accident, Norway got a substantial part of the cesium isotopes released. The radioactive fallout followed closely the rainfall and was mainly concentrated to some thin populated areas in the central parts of the country. The total fallout of the cesium isotopes was approximately 2300 TBq (Cs-137) and 1200 TBq (Cs-134). The average for the country was 11 kBq/m 2 with a variation from 1.5 to 40 kBq/m 2 for the 19 different counties of the country. The fallout resulted in contamination of food products from some areas, mainly meat from reindeer and sheep, as well as freshwater fish. A small fraction of the food produced in 1986 was not sold due to the regulations enforced. The average radiation dose to the Norwegian population during the first year after the accident was approximately 0.3 mSv (0.1 mSv from external radiation and about 0.2 mSv from foodstuff). This first year extra dose is approximately 5% of the average normal background dose in Norway

  1. Natural background radiation and population dose distribution in India

    International Nuclear Information System (INIS)

    Nambi, K.S.V.; Bapat, V.N.; David, M.; Sundaram, V.K.; Sunta, C.M.; Soman, S.D.

    1986-01-01

    A country-wide survey of the outdoor natural background gamma radiation levels has been made using mailed thermoluminescent dosimeters (TLDs). The salient features of the results are: (1) The air-kerma levels and the population doses in various states follow log-normal and normal distributions respectively. (2) The national average value for the air dose (air-kerma) is 775 ± 370 (1σ)μGy/y. (3) The lowest air-kerma recorded is 0.23 mGy/y at Minicoy (Laccadive Islands) and the highest is 26.73 mGy/y at Chavra (monazite areas, Kerala). (4) There are significant temporal variation s (even as high as ± 40 per cent) of the background radiation level at many locations and at least in 10 locations where radon/thoron measurements are available, these could be associated with the seasonal variations in radon/thoron levels. (5) The mail control TLDs indicate a country-wide average value of 785 ± 225 μGy/y for the air-kerma which can be considered to provide a truly national average value for the natural background radiation level in India. (6) The mean natural radiation per caput for the country works out to be 690 ± 200 (1σ) Sv/y. (7) The natural radiation per caput seems to be maximum for Andhra Pradesh (1065 ± 325 μSv/y) and minimum for Maharashtra (370 ± 80 μSv/y). (8) The population dose from the external natural background radiation is estimated to be half a million person-Sievert. (9) Assuming 1 CRP risk factor, it can be estimated that just one out of the 43 cancer deaths occurring on an average per 100,000 population in India, can be attributed to the external natural background radiation. (author). 18 refs., 13 tabs., 9 figs

  2. Inactivation of bacteria in sewage sludge by ionizing radiation, heat, and thermoradiation

    International Nuclear Information System (INIS)

    Brandon, J.R.; Langley, S.L.

    1976-01-01

    For purposes of animal feeding or fertilizer usage on edible crops, sewage sludge must be free of pathogenic organisms. Bacterial inactivation by a combination of heat and irradiation is shown to be effective. These results must be viewed in conjunction with those from studies of parasite egg inactivation, virus inactivation, and physical-chemical benefits in order to make a fair assessment of the value of the thermoradiation treatment compared to other possible sludge treatment processes

  3. Method of inactivating reproducible forms of mycoplasma in biological preparations

    International Nuclear Information System (INIS)

    Veber, P.; Jurmanova, K.; Lesko, J.; Hana, L.; Veber, V.

    1978-01-01

    Inactivation of mycoplasms in biological materials was achieved using gamma radiation with a dose rate of 1x10 4 to 5x10 6 rads/h for 1 to 250 hours. The technique is advantageous for allowing the inactivation of the final form of products (tablets, vaccines, etc.). (J.P.)

  4. Oltar Sv. Jeronima u crkvi Sv. Šime u Zadru i radionica Bettamelli

    Directory of Open Access Journals (Sweden)

    Bojan Goja

    2012-12-01

    Full Text Available U radu se na temelju arhivskih podataka govori o oltaru Sv. Jeronima u crkvi Sv. Šime u Zadru. Od ranije se zna da je oltar dala podići i o njegovu se uređenju brinula bratovština hrvatskih i albanskih vojnika (Croatti a cavallo i Soldati Albanesi u službi Mletačke Republike, osnovana 1675. godine u Zadru. Novim je arhivskim istraživanjima utvrđeno da je dana 26. rujna 1694. godine bratovština odobrila izdatak u iznosu od 200 srebrnih dukata, namijenjenih venecijanskim klesarima braći Bettamelli kao predujam za izradu oltara te da su radovi na njegovu podizanju započeti u travnju 1696. godine. Na temelju zapisa o gradnji oltara iznijeta je pretpostavka da se grb na istočnom pilastru stipesa oltara, ranije povezivan s predstavnicima obitelji Civran, odnosi na zadarskog plemića i istaknutog zapovjednika u mletačkoj vojsci, Šimuna Fanfognu (Zadar, 7. travnja 1663. - Lendinara, 6. ožujka 1707. koji je obavljao i dužnost prokuratora oltara. Brojni radovi na uređenju oltara i kapele Sv. Jeronima obavljani su i tijekom čitavog 18. stoljeća, a na njima su bili uposleni brojni mjesni majstori različitih struka: graditelji Antonio Piovesana (1742. i Antonio Bernardini (1789., oltarist Girolamo Picco (1756., marangon Domenico Tomaselli (1743., kovač Antonelli (1744. te zlatari Zorzi Cullisich (1738., Nicolò Giurovich (1752. i Giuseppe Rado (1755.. Donose se još neke zanimljivosti vezane uz uređenje oltara i djelovanje bratovštine Sv. Jeronima.

  5. PET/CT-guided Interventions: Personnel Radiation Dose

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, E. Ronan, E-mail: ronan@ronanryan.com; Thornton, Raymond; Sofocleous, Constantinos T.; Erinjeri, Joseph P. [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States); Hsu, Meier [Memorial Sloan-Kettering Cancer Center, Department of Epidemiology and Biostatistics (United States); Quinn, Brian; Dauer, Lawrence T. [Memorial Sloan-Kettering Cancer Center, Department of Medical Physics (United States); Solomon, Stephen B. [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States)

    2013-08-01

    PurposeTo quantify radiation exposure to the primary operator and staff during PET/CT-guided interventional procedures.MethodsIn this prospective study, 12 patients underwent PET/CT-guided interventions over a 6 month period. Radiation exposure was measured for the primary operator, the radiology technologist, and the nurse anesthetist by means of optically stimulated luminescence dosimeters. Radiation exposure was correlated with the procedure time and the use of in-room image guidance (CT fluoroscopy or ultrasound).ResultsThe median effective dose was 0.02 (range 0-0.13) mSv for the primary operator, 0.01 (range 0-0.05) mSv for the nurse anesthetist, and 0.02 (range 0-0.05) mSv for the radiology technologist. The median extremity dose equivalent for the operator was 0.05 (range 0-0.62) mSv. Radiation exposure correlated with procedure duration and with the use of in-room image guidance. The median operator effective dose for the procedure was 0.015 mSv when conventional biopsy mode CT was used, compared to 0.06 mSv for in-room image guidance, although this did not achieve statistical significance as a result of the small sample size (p = 0.06).ConclusionThe operator dose from PET/CT-guided procedures is not significantly different than typical doses from fluoroscopically guided procedures. The major determinant of radiation exposure to the operator from PET/CT-guided interventional procedures is time spent in close proximity to the patient.

  6. Occupational radiation exposure in nuclear medicine department in Kuwait

    Science.gov (United States)

    Alnaaimi, M.; Alkhorayef, M.; Omar, M.; Abughaith, N.; Alduaij, M.; Salahudin, T.; Alkandri, F.; Sulieman, A.; Bradley, D. A.

    2017-11-01

    Ionizing radiation exposure is associated with eye lens opacities and cataracts. Radiation workers with heavy workloads and poor protection measures are at risk for vision impairment or cataracts if suitable protection measures are not implemented. The aim of this study was to measure and evaluate the occupational radiation exposure in a nuclear medicine (NM) department. The annual average effective doses (Hp[10] and Hp[0.07]) were measured using calibrated thermos-luminescent dosimeters (TLDs; MCP-N [LiF:Mg,Cu,P]). Five categories of staff (hot lab staff, PET physicians, NM physicians, technologists, and nurses) were included. The average annual eye dose (Hp[3]) for NM staff, based on measurements for a typical yearly workload of >7000 patients, was 4.5 mSv. The annual whole body radiation (Hp[10]) and skin doses (Hp[0.07]) were 4.0 and 120 mSv, respectively. The measured Hp(3), Hp(10), and Hp(0.07) doses for all NM staff categories were below the dose limits described in ICRP 2014 in light of the current practice. The results provide baseline data for staff exposure in NM in Kuwait. Radiation dose optimization measures are recommended to reduce NM staff exposure to its minimal value.

  7. Effect of incubation temperatures for inactivation of Escherichia coli and related bacteria after gamma-irradiation

    International Nuclear Information System (INIS)

    Nakauma, Makoto; Ito, Hitoshi; Tada, Mikiro

    2000-01-01

    Irradiated fresh meat or fishery products have been expected to store and distribute under refrigerated temperature below 10degC. From previous reports, growth of coliform bacteria in these products were suppressed by gamma-irradiation below expected doses obtained at 30-37degC. This research was performed to observe the irradiation effect on the inactivation of Escherichia coli and related bacteria at different incubation temperatures of 10-40degC on plate agar after irradiation. From this study, D10 values of all strains decreased 17- 45% at 10degC compared with maximum D10 values at 30- 40degC. Radiation sensitivities were related to the ability to grow at low temperatures in which psychrotrophic type E. coli A4-1 indicated most sensitive to radiation, next of Salmonella enteritidis YK-2, E. coli S2, B4 whereas most resistant at Enterobacter agglomerans K3-1. (author)

  8. Effect of incubation temperatures for inactivation of Escherichia coli and related bacteria after gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Nakauma, Makoto; Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Tada, Mikiro [Okayama Univ. (Japan). Faculty of Agriculture

    2000-09-01

    Irradiated fresh meat or fishery products have been expected to store and distribute under refrigerated temperature below 10degC. From previous reports, growth of coliform bacteria in these products were suppressed by gamma-irradiation below expected doses obtained at 30-37degC. This research was performed to observe the irradiation effect on the inactivation of Escherichia coli and related bacteria at different incubation temperatures of 10-40degC on plate agar after irradiation. From this study, D10 values of all strains decreased 17- 45% at 10degC compared with maximum D10 values at 30- 40degC. Radiation sensitivities were related to the ability to grow at low temperatures in which psychrotrophic type E. coli A4-1 indicated most sensitive to radiation, next of Salmonella enteritidis YK-2, E. coli S2, B4 whereas most resistant at Enterobacter agglomerans K3-1. (author)

  9. Svømmehaller og krav til energieffektivitet

    OpenAIRE

    Øen, Martin Nerhus

    2010-01-01

    Svømmehaller er en spesiell bygningstype, som med høy innendørs temperatur og luftfuktighet, skiller seg fra andre bygninger som boliger og kontorbygg. Den høye innetemperaturen, forbruket av varmtvann, og fordampning fra svømmebassenget fører til et stort energiforbruk. Svømmehaller er ikke gitt egne krav i Teknisk forskrift til plan- og bygningsloven (TEK), til tross for at energiforbruket kan være tre ganger høyere enn kravene gitt for idrettshaller. Målet med denne rapporten er å finne fo...

  10. Levetiracetam reverses synaptic deficits produced by overexpression of SV2A.

    Directory of Open Access Journals (Sweden)

    Amy Nowack

    Full Text Available Levetiracetam is an FDA-approved drug used to treat epilepsy and other disorders of the nervous system. Although it is known that levetiracetam binds the synaptic vesicle protein SV2A, how drug binding affects synaptic functioning remains unknown. Here we report that levetiracetam reverses the effects of excess SV2A in autaptic hippocampal neurons. Expression of an SV2A-EGFP fusion protein produced a ∼1.5-fold increase in synaptic levels of SV2, and resulted in reduced synaptic release probability. The overexpression phenotype parallels that seen in neurons from SV2 knockout mice, which experience severe seizures. Overexpression of SV2A also increased synaptic levels of the calcium-sensor protein synaptotagmin, an SV2-binding protein whose stability and trafficking are regulated by SV2. Treatment with levetiracetam rescued normal neurotransmission and restored normal levels of SV2 and synaptotagmin at the synapse. These results indicate that changes in SV2 expression in either direction impact neurotransmission, and suggest that levetiracetam may modulate SV2 protein interactions.

  11. The Effect of NPP's Stack Height to Radiation Dose

    International Nuclear Information System (INIS)

    Pandi, Liliana Yetta; Rohman, Budi

    2003-01-01

    The purpose of dose calculation for accidents is to analyze the capability of NPP to maintain the safety of public and workers in case an accident occurs on the Plant in a site. This paper calculates the Loss of Coolant Accident in PWR plant. The calculation results shows that no risks of serious radiation exposure are given to the neighboring public even if such a large accident occurred, and the effect of stack height can be predicted by analysis of the calculation results. The whole dose is calculated for some location (100 m, 300 m, 500 m, 700 m, 900 m, 1500 m, and 2000 m) with three difference stack height i.e. 0 m, 40 m and 100 m. The result of the whole dose calculation is under permitted criteria for whole dose : 0.25 Sv and thyroid dose : 3.0 Sv. The calculation of radiation dose in this paper use EEDCDQ code

  12. Some human activities to decrease public radiation dose

    International Nuclear Information System (INIS)

    Pan Ziqiang; Guo Minqiang

    1994-01-01

    The necessity of studying the variations in radiation levels from the balance viewpoint is discussed. Some human activities may increase, while others may decrease, radiation dose to population. In 1988, China's investigation showed that travel by air caused a raise of population collective dose by 3.6 x 10 1 man·Sv, while travel by ship, train and vehicle lead to a drop of 5.36 x 10 2 man·Sv, and that dwellings of coal cinder brick decreased collective dose by 3.5 x 10 3 man·Sv, while buildings of reinforced concrete structure increased collective dose by 3.7 x 10 3 man·Sv. It is inadequate to only study those activities which may increase radiation levels

  13. Sensitivity of clostridium acetobutylicum to oxygen and ionizing radiation

    International Nuclear Information System (INIS)

    Sozer, A.C.; Adler, H.I.; Machanoff, R.; Haney, S.

    1984-01-01

    The authors are studying the sensitivity of four strains of the obligate anaerobe, Clostridium acetobutylicum, to oxygen and ionizing radiation. Anaerobic bacteria are useful for such studies because of the absence of elaborate oxygen detoxification mechanisms that are found in aerobes. Their experiments make use of sterile membrane fragments from Escherichia coli that rapidly remove molecular oxygen from media and permit growth of anaerobes without the use of reducing agents or anaerobic chambers. Of the four strains examined for sensitivity to ionizing radiation under anaerobic conditions, one has an LD/sub 50/ of -- 25 krads and the others have an LD/sub 50/ of -- 7 krads. The radiation resistant strain is also relatively resistant to oxygen exposure. Sensitivity to oxygen was determined by diluting cells in buffer at 28 0 and bubbling with air. An exposure to air for 40 min induced only slight inactivation in the radiation resistant strain. All strains are capable of removing oxygen from complex media but there is no apparent correlation between this oxygen consuming reaction and inactivation by either oxygen or radiation

  14. Modelling and application of the inactivation of microorganism

    International Nuclear Information System (INIS)

    Oğuzhan, P.; Yangılar, F.

    2013-01-01

    Prevention of consuming contaminated food with toxic microorganisms causing infections and consideration of food protection and new microbial inactivation methods are obligatory situations. Food microbiology is mainly related with unwanted microorganisms spoiling foods during processing and transporting stages and causing diseases. Determination of pathogen microorganisms is important for human health to define and prevent dangers and elongate shelf life. Inactivation of pathogen microorganisms can provide food security and reduce nutrient losses. Microbial inactivation which is using methods of food protection such as food safety and fresh. With this aim, various methods are used such as classical thermal processes (pasteurisation, sterilisation), pressured electrical field (PEF), ionised radiation, high pressure, ultrasonic waves and plasma sterilisation. Microbial inactivation modelling is a secure and effective method in food production. A new microbiological application can give useful results for risk assessment in food, inactivation of microorganisms and improvement of shelf life. Application and control methods should be developed and supported by scientific research and industrial applications

  15. Radiation shield analysis for a manned Mars rover

    International Nuclear Information System (INIS)

    Morley, N.J.; ElGenk, M.S.

    1991-01-01

    Radiation shielding for unmanned space missions has been extensively studied; however, designs of man-rated shields are minimal. Engle et al.'s analysis of a man-rated, multilayered shield composed of two and three cycles (a cycle consists of a tungsten and a lithium hydride layer) is the basis for the work reported in this paper. The authors present the results of a recent study of shield designs for a manned Mars rover powered by a 500-kW(thermal) nuclear reactor. A train-type rover vehicle was developed, which consists of four cars and is powered by an SP-100-type nuclear reactor heat source. The maximum permissible dose rate (MPD) from all sources is given by the National Council on Radiation Protection and Measurements as 500 mSv/yr (50 rem/yr) A 3-yr Mars mission (2-yr round trip and 1-yr stay) will deliver a 1-Sv natural radiation dose without a solar particle event, 450 mSv/yr in flight, and an additional 100 mSv on the planet surface. An anomalously large solar particle event could increase the natural radiation dose for unshielded astronauts on the Martian surface to 200 mSv. This limits the MPD to crew members from the nuclear reactor to 300 mSv

  16. Cell and molecular biology of simian virus 40: implications for human infections and disease

    Science.gov (United States)

    Butel, J. S.; Lednicky, J. A.

    1999-01-01

    Simian virus 40 (SV40), a polyomavirus of rhesus macaque origin, was discovered in 1960 as a contaminant of polio vaccines that were distributed to millions of people from 1955 through early 1963. SV40 is a potent DNA tumor virus that induces tumors in rodents and transforms many types of cells in culture, including those of human origin. This virus has been a favored laboratory model for mechanistic studies of molecular processes in eukaryotic cells and of cellular transformation. The viral replication protein, named large T antigen (T-ag), is also the viral oncoprotein. There is a single serotype of SV40, but multiple strains of virus exist that are distinguishable by nucleotide differences in the regulatory region of the viral genome and in the part of the T-ag gene that encodes the protein's carboxyl terminus. Natural infections in monkeys by SV40 are usually benign but may become pathogenic in immunocompromised animals, and multiple tissues can be infected. SV40 can replicate in certain types of simian and human cells. SV40-neutralizing antibodies have been detected in individuals not exposed to contaminated polio vaccines. SV40 DNA has been identified in some normal human tissues, and there are accumulating reports of detection of SV40 DNA and/or T-ag in a variety of human tumors. This review presents aspects of replication and cell transformation by SV40 and considers their implications for human infections and disease pathogenesis by the virus. Critical assessment of virologic and epidemiologic data suggests a probable causative role for SV40 in certain human cancers, but additional studies are necessary to prove etiology.

  17. Mesothelioma mortality in Europe: impact of asbestos consumption and simian virus 40

    Directory of Open Access Journals (Sweden)

    Rehak Peter

    2006-11-01

    Full Text Available Abstract Background It is well established that asbestos is the most important cause of mesothelioma. The role of simian virus 40 (SV40 in mesothelioma development, on the other hand, remains controversial. This potential human oncogene has been introduced into various populations through contaminated polio vaccines. The aim of this study was to investigate whether the possible presence of SV40 in various European countries, as indicated either by molecular genetic evidence or previous exposure to SV40-contaminated vaccines, had any effect on pleural cancer rates in the respective countries. Methods We conducted a Medline search that covered the period from January 1969 to August 2005 for reports on the detection of SV40 DNA in human tissue samples. In addition, we collected all available information about the types of polio vaccines that had been used in these European countries and their SV40 contamination status. Results Our ecological analysis confirms that pleural cancer mortality in males, but not in females, correlates with the extent of asbestos exposure 25 – 30 years earlier. In contrast, neither the presence of SV40 DNA in tumor samples nor a previous vaccination exposure had any detectable influence on the cancer mortality rate in neither in males (asbestos-corrected rates nor in females. Conclusion Using the currently existing data on SV40 prevalence, no association between SV40 prevalence and asbestos-corrected male pleural cancer can be demonstrated.

  18. Use of radiation and radiation practices in 1993. Events and statistics

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R [ed.

    1994-05-01

    In the end of the year 1993 there were in force 1740 safety licences for the use of radiation granted by the Finnish Centre for Radiation and Nuclear Safety (STUK). In addition to this there were 2100 places for dental x-ray activities in Finland. All together 12726 radiation sources and 313 radioisotope laboratories were in use. The import of radioactive substances was 3.9 x 10 {sup 15} Bq and the export 2.5 x 10 {sup 13} Bq. The production of short-lived isotopes was 1.3 x 10 {sup 13} Bq. The monitoring of personal radiation doses was organized for 11171 workers and 1299 working places. The annual dose (the integrated readings of dosemeters) was greater than registration threshold for 24% of workers. The collective dose (the sum of the results of the dose measurements) registered to the Finnish Dose Register was 6.9 manSv; 74% belonged to the workers of nuclear power plants. The sum of the personal doses measured in 1993 were for three interventional radiologists and fifteen workers in nuclear power plants 20 mSv or more. The effective doses were in each case under the annual dose limit of 50 mSv. The effective doses for the interventional radiologists were under 20 mSv. (7 figs., 16 tabs.).

  19. Radiation doses deriving from patients undergoing 111In-DTPA-d-Phe-1-octreotide scintigraphy

    International Nuclear Information System (INIS)

    Kurtaran, A.; Pfreitfellner, J.; Smith-Jones, P.; Schaffarich, P.; Niederle, B.; Raderer, M.; Virgolini, I.; Bergmann, H.; Havlik, E.

    1997-01-01

    The purpose of this study was to estimate the radiation doses to nursing staff, other patients, accompanying persons and family members deriving from patients undergoing 111 In-DTPA-d-Phe-1-octreotide ( 111 In-OCT) scintigraphy. Dose rates were measured from 16 patients who had received an intravenous injection of 140±40 MBq 111 In-OCT. The measurements were performed at three different distances (0.5, 1 and 2 m) at 10-20 min, 5-7 h and 24 h (and in some cases, up to 48 h) after administration of 111 In-OCT. The effective half-lives of the biexponential decrease of the dose rates were estimated to be 2.94±0.27 h (T 1 ) and 65.17±0.58 h (T 2 ). The calculated maximum dose to other persons in the waiting area was 27.2 μSv, to family members 61.5 μSv, to nursing staff in a ward 24.1 μSv and to neighbouring patients in the ward 69.5 μSv. Our results clearly demonstrate that the calculated maximum radiation exposure to accompanying persons, personnel, family members and other patients is well below the maximum annual dose limit for non-professionally exposed persons. (orig.)

  20. Effects of radiation

    International Nuclear Information System (INIS)

    Masse, R.

    2006-01-01

    The medical consequences of a whole-body irradiation come from the destruction of cells and inflammatory reactions it provokes. The most sensitive organs are the tissues that actively split. The embryo is particularly sensitive, from 200 mSv for the effects on the brain development. The reproduction functions are reached for man from 2000 mSv, the ovary sensitivity is less, the oocytes do not split after the fetus life. For adult the bone marrow outrage leads to the disappearing of blood cells (4000 mSv). The doses from 6000 to 10000 mSv lead the failure of the digestive system and lung. for the upper doses every tissue is reached, particularly by the effects on cells of blood vessels. Important brain dysfunctions appear beyond 10000 mSv. As regards the delayed effects of overexposures the epidemiology brings to light sanitary consequences of the exposure of the population to the ionizing radiations and requires that all the possible factors associated for that purpose are considered. About hereditary effects, it appears that moderate acute radiation exposures of even a relatively large human population must have little impact, in spite of the rate of spontaneous congenital deformations is of the order of 6 %. For the induction of cancers, it is not observed excess for doses lower than 200 mSv for adults and 100 mSv for children (the populations studied are survival people of hiroshima and Nagasaki, patients treated by irradiation, uranium miners, children exposed to radioactive iodine after Chernobylsk accident). To simplify an expression of the risk has been fixed to 5% of induced cancer by Sv for population and 4% by Sv for workers, the different being explained by the demography and the sensitivity of the youngest age groups. As regards the low doses of radiations, a bundle of convergent epidemiological observations notices the absence of effects of the low doses rates. Biological mechanisms, notably of repair are approached, then certain accidents (Goiania

  1. STUDY OF NATURAL RADIOACTIVITY (226Ra, 232Th AND 40K) IN SOIL SAMPLES FOR THE ASSESSMENT OF AVERAGE EFFECTIVE DOSE AND RADIATION HAZARDS.

    Science.gov (United States)

    Bangotra, Pargin; Mehra, Rohit; Kaur, Kirandeep; Jakhu, Rajan

    2016-10-01

    The activity concentration of 226 Ra (radium), 232 Th (thorium) and 40 K (potassium) has been measured in the soil samples collected from Mansa and Muktsar districts of Punjab (India) using NaI (Tikl) gamma detector. The concentration of three radionuclides ( 226 Ra, 232 Th and 40 K) in the studied area has been varied from 18±4 to 46±5, 53±7 to 98±8 and 248±54 to 756±110 Bq kg -1 , respectively. Radium equivalent activities (Ra eq ) have been calculated in soil samples for the assessment of the radiation hazards arising due to the use of these soil samples. The absorbed dose rate of 226 Ra, 232 Th and 40 K in studied area has been varied from 8 to 21, 33 to 61 and 9 to 25 nGy h -1 , respectively. The corresponding indoor and outdoor annual effective dose in studied area was 0.38 and 0.09 mSv, respectively. The external and internal hazard has been also calculated for the assessment of radiation hazards in the studied area. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. PET/CT-guided Interventions: Personnel Radiation Dose

    International Nuclear Information System (INIS)

    Ryan, E. Ronan; Thornton, Raymond; Sofocleous, Constantinos T.; Erinjeri, Joseph P.; Hsu, Meier; Quinn, Brian; Dauer, Lawrence T.; Solomon, Stephen B.

    2013-01-01

    PurposeTo quantify radiation exposure to the primary operator and staff during PET/CT-guided interventional procedures.MethodsIn this prospective study, 12 patients underwent PET/CT-guided interventions over a 6 month period. Radiation exposure was measured for the primary operator, the radiology technologist, and the nurse anesthetist by means of optically stimulated luminescence dosimeters. Radiation exposure was correlated with the procedure time and the use of in-room image guidance (CT fluoroscopy or ultrasound).ResultsThe median effective dose was 0.02 (range 0–0.13) mSv for the primary operator, 0.01 (range 0–0.05) mSv for the nurse anesthetist, and 0.02 (range 0–0.05) mSv for the radiology technologist. The median extremity dose equivalent for the operator was 0.05 (range 0–0.62) mSv. Radiation exposure correlated with procedure duration and with the use of in-room image guidance. The median operator effective dose for the procedure was 0.015 mSv when conventional biopsy mode CT was used, compared to 0.06 mSv for in-room image guidance, although this did not achieve statistical significance as a result of the small sample size (p = 0.06).ConclusionThe operator dose from PET/CT-guided procedures is not significantly different than typical doses from fluoroscopically guided procedures. The major determinant of radiation exposure to the operator from PET/CT-guided interventional procedures is time spent in close proximity to the patient

  3. Ingestion dose from 238U, 232Th, 226Ra, 40K and 137CS in cereals, pulses and drinking water to adult population in a high background radiation area, Odisha (India)

    International Nuclear Information System (INIS)

    Lenka, P.; Sahoo, S. K.; Mohapatra, S.; Patra, A. C.; Dubey, J. S.; Vidyasagar, D.; Tripathi, R. M.; Puranik, V. D.

    2013-01-01

    A natural high background radiation area is located in Chhatrapur, Odisha in the eastern part of India. The inhabitants of this area are exposed to external radiation levels higher than the global average background values, due to the presence of uranium, thorium and its decay products in the monazite sands bearing placer deposits in its beaches. The concentrations of 232 Th, 238 U, 226 Ra, 40 K and 137 Cs were determined in cereals (rice and wheat), pulses and drinking water consumed by the population residing around this region and the corresponding annual ingestion dose was calculated. The annual ingestion doses from cereals, pulses and drinking water varied in the range of 109.4-936.8, 10.2-307.5 and 0.5-2.8 μSv y -1 , respectively. The estimated total annual average effective dose due to the ingestion of these radionuclides in cereals, pulses and drinking water was 530 μSv y -1 . The ingestion dose from cereals was the highest mainly due to a high consumption rate. The highest contribution of dose was found to be from 226 Ra for cereals and drinking water and 40 K was the major dose contributor from the intake of pulses. The contribution of man-made radionuclide 137 Cs to the total dose was found to be minimum. 226 Ra was found to be the largest contributor to ingestion dose from all sources. (authors)

  4. Estimated radiation exposure of German commercial airline cabin crew in the years 1960-2003 modeled using dose registry data for 2004-2015.

    Science.gov (United States)

    Wollschläger, Daniel; Hammer, Gaël Paul; Schafft, Thomas; Dreger, Steffen; Blettner, Maria; Zeeb, Hajo

    2018-05-01

    Exposure to ionizing radiation of cosmic origin is an occupational risk factor in commercial aircrew. In a historic cohort of 26,774 German aircrew, radiation exposure was previously estimated only for cockpit crew using a job-exposure matrix (JEM). Here, a new method for retrospectively estimating cabin crew dose is developed. The German Federal Radiation Registry (SSR) documents individual monthly effective doses for all aircrew. SSR-provided doses on 12,941 aircrew from 2004 to 2015 were used to model cabin crew dose as a function of age, sex, job category, solar activity, and male pilots' dose; the mean annual effective dose was 2.25 mSv (range 0.01-6.39 mSv). In addition to an inverse association with solar activity, exposure followed age- and sex-dependent patterns related to individual career development and life phases. JEM-derived annual cockpit crew doses agreed with SSR-provided doses for 2004 (correlation 0.90, 0.40 mSv root mean squared error), while the estimated average annual effective dose for cabin crew had a prediction error of 0.16 mSv, equaling 7.2% of average annual dose. Past average annual cabin crew dose can be modeled by exploiting systematic external influences as well as individual behavioral determinants of radiation exposure, thereby enabling future dose-response analyses of the full aircrew cohort including measurement error information.

  5. First assessment of individual monitoring of medical workers occupationally exposed to ionizing radiation in Burkina Faso

    International Nuclear Information System (INIS)

    Yakoro, A.; Nobila Ouédraogo, Salimata Traoré

    2010-01-01

    This paper reports the results of monitoring of medical workers occupationally exposed to ionizing radiation as a consequence of exposure to X-rays, from 2007 to 2010, in Burkina Faso. The radiation exposure monitoring was made with thermoluminescent dosimeters (TLD-100) type 0110 and the reader used was Harshaw 4500. The medical establishments. subscribers were provided with personal dosimeters (measuring Hp (10) and Hp (0.07)) and dosimeters for background and workplace exposure (H*10) measurement. The dosimeters have been worn for periods of 2 months each. The number of establishments subscribed and workers monitored has gradually increased from 4 radiology establishments with 13 workers monitored at September 2007 to 23 subscribers with 121 workers monitored at the end of April 2010. 13 establishments were still working without monitoring. From September 2007 to April 2010, no individual annual dose limit has really been reached. 88.16% of the 2 months dose values of personal dosimeters were below 0.1mSv, the detection limit and 96.61% of Hp (10) bimonthly values were below 3.33mSv. The workplace exposure monitoring values were often low (varying from 0.00mSv to 40.45mSv). 87.08% of the values of H*(10) were below 3.33mSv, the upper limit of Hp (10) for a period of 2 months. Low values of individual dose have also been recorded despite of high values of workplace monitoring. This allowed to state that the workers monitored were not exposed to a major risk. Nevertheless, 13 TLD have been lost and 3 damaged by subscribers (out of 1504 TLD provided). 26 times (out of 240), background measurement and workplace exposure monitoring dosimeters have been placed at the improper location. Therefore, sensitization of the establishments using ionizing radiation should be reinforced and the national regulations should impose radiation monitoring (author)

  6. Exposure to background radiation in Australia

    International Nuclear Information System (INIS)

    Solomon, S.B.

    1997-01-01

    The average effective dose received by the Australian population is estimated to be ∼1.8 mSv / year. One half of this exposure arises from exposure from terrestrial radiation and cosmic rays, the remainder from radionuclides within the body and from inhalation of radon progeny. This paper reviews a number of research programmes carried out by the Australian Radiation Laboratory to study radiation exposure from natural background, particularly in the workplace and illustrate approaches to the quantification and management of exposure to natural radiation. The average radiation doses to the Australian population are relatively low; the average annual radon concentration ranged from 6 Bq m -3 in Queensland to 16 Bq m -3 in the Australian Capital Territory (ACT). Of more importance is the emerging issue of exposure to elevated background radiation in the workplace. Two situation are presented; the radiation exposure to air crues and show cave tour guides. Annual doses up to 3.8 mSv were estimated for international crew members while the highest estimate for show cave tour guides was 9 mSv per year

  7. Studying and measuring the gamma radiation doses in Homs city

    International Nuclear Information System (INIS)

    Sofaan, A. H.

    2001-01-01

    The gamma radiation dose was measured in Homs city by using many portable dosimeters (electronic dosimeter and Geiger-Muller). The measurements were carried out in the indoor and outdoor buildings, for different time period, through one year (1999-2000). High purity germanium detector with low back ground radiation (HpGe) was used to determine radiation element contained in some building and the surrounding soil. The statistical analysis laws were applied to make sure that the measured dose distribution around average value is normal distribution. The measurement indicates that the gamma indoor dose varies from 312μSv/y to 511μSv/y, with the average annual dose of 385μSv/y. However the gamma outdoor dose rate varies from 307μSv/y to 366μSv/y with an average annual dose 385μSv/y. The annual outdoor gamma radiation dose is about %16 lower than the outdoor dose in Homs City. These measurements have indicated that environmental gamma doses in Homs City are relatively low. This is because that most of the soils and rocks in the area are limestone. (author)

  8. Use of radiation and radiation practices 1994. Events and statistics

    International Nuclear Information System (INIS)

    Havukainen, R.

    1995-05-01

    In Finland, there were 1,745 valid safety licences for the use of radiation at the end of 1994. In addition, 2,050 sites were included in the compulsory registration for dental x-ray diagnostics. The register of the Finnish Centre for Radiation and Nuclear Safety listed 12,794 radiation sources and 316 radionuclide laboratories. The import of radioactive substances amounted to 4.6x10 15 Bq and export to 2.2x10 13 Bq. A total of 1.4x10 13 Bq of short-lived radionuclides were produced in Finland. Workers monitored for radiation exposure included 11,147 employees on 1,294 work sites. Of these, 27% received an annual dose exceeding the recording threshold. The total dose recorded in the dose register (sum of personal dosemeter readings) was 75 man Sv in 1994, nuclear power plant employees accounting for 70% of this total. The annual dosemeter reading of ten medical doctors (radiologists, international radiologists and cardiologists) and five nuclear power plant employees was equal to or in excess of 20 mSv. Effective dose, however, did not exceed the dose limit of 50 mSv established for a one-year monitoring period

  9. Inactivation by gamma irradiation of animal viruses in simulated laboratory effluent

    International Nuclear Information System (INIS)

    Thomas, F.C.; Ouwerkerk, T.; McKercher, P.

    1982-01-01

    Several animal viruses were treated with gamma radiation from a 60 Co source under conditions which might be found in effluent from an animal disease laboratory. Swine vesicular disease virus, vesicular stomatitis virus, and blue-tongue virus were irradiated in tissues from experimentally infected animals. Pseudorabies virus, fowl plague virus, swine vesicular disease virus, and vesicular stomatitis virus were irradiated in liquid animal feces. All were tested in animals and in vitro. The D 10 values, that is, the doses required to reduce infectivity by 1 log 10 , were not apparently different from those expected from predictions based on other data and theoretical considerations. The existence of the viruses in pieces of tissues or in liquid feces made no differences in the efficacy of the gamma radiation for inactivating them. Under the ''worst case'' conditions (most protective for virus) simulated in this study, no infectious agents would survive 4.0 Mrads

  10. Eating habits and internal radiation exposures in Japanese

    International Nuclear Information System (INIS)

    Shiraishi, Kunio

    1995-01-01

    Recently, annual dose equivalent for Japanese was estimated to be 3.75 mSv. Medical radiation exposures (2.25 mSv/y) and exposures from natural sources of radiation (1.48 mSv/y) were the major contributors to this dose. Dietary intakes of both natural and man-made radionuclides directly related to internal exposures. In this paper, internal doses received only through ingestion of radionuclides in food are described; internal doses through inhalation have been excluded. First, the representative intakes of radionuclides for Japanese were estimated from the literature. Second, the annual dose equivalents were calculated according to intakes of individual radionuclides and weighted committed dose equivalents (Sv/Bq) of the International Commission on Radiological Protection Pub. 30. Total annual doses through radiation of natural sources and man-made sources, were estimated as 0.35 mSv and 0.001 mSv, respectively. Furthermore, the effects of imported foods on internal dose in Japanese were calculated preliminarily, because the contribution of imported foods to Japanese eating habits is increasing annually and will not be negligible when assessing internal dose in the near future. (author)

  11. Operator radiation exposure during right or left transradial coronary angiography: A phantom study

    International Nuclear Information System (INIS)

    Sciahbasi, Alessandro; Rigattieri, Stefano; Sarandrea, Alessandro; Cera, Maria; Di Russo, Cristian; Fedele, Silvio; Romano, Silvio; Pugliese, Francesco Rocco; Penco, Maria

    2015-01-01

    Background: Previous studies showed a possible lower radiation dose absorbed by operators comparing LRA and RRA for percutaneous coronary procedures. The reasons of this lower radiation dose are not well known. The aim of this study was to evaluate the radiation dose absorbed by operators comparing left with right radial access (LRA and RRA respectively) during a simulated diagnostic coronary angiography using a phantom. Methods: A coronary angiography examination was simulated on a phantom by 5 operators using eight projections with 5 seconds fluoroscopy each. Each operator was equipped with 4 electronic dosimeters placed at thorax, at left wrist, at left head and at hip level. Radiation doses were expressed in picosievert and normalized by dose area product. Results: LRA compared to RRA was associated with a significant lower operator dose at wrist (36 pSv/cGYcm"2 [IQR 18–59 pSv/cGYcm"2] and 48 pSv/cGYcm"2 [IQR 22–148 pSv/cGYcm"2] respectively, p = 0.01) and thorax (3 pSv/cGYcm"2 [IQR 2–5 pSv/cGYcm"2] and 10 pSv/cGYcm"2 [6–23 pSv/cGYcm"2] respectively, p < 0.001) but with a significant higher radiation dose at hip level (102 pSv/cGYcm"2 [IQR 44–199 pSv/cGYcm"2] and 67 pSv/cGYcm"2 [IQR 39–132 pSv/cGYcm"2] respectively, p = 0.02). Conversely the radiation dose at left side of the head did not show significant differences between the two approaches. Conclusions: In this phantom study simulating a diagnostic coronarography the use of LRA compared to RRA was associated with a significant lower radiation dose at wrist and thorax but with an increased dose at hip level. Summary: To evaluate the radiation dose absorbed by operators comparing left with right radial access (LRA and RRA respectively) we simulated a diagnostic coronary angiography using a dedicated phantom. Operators were equipped with dedicated electronic dosimeters at wrist, hip, head and thorax level. LRA compared to RRA was associated with a significant lower operator dose at wrist and thorax

  12. Cosmic radiation dose in the aircraft

    International Nuclear Information System (INIS)

    Vukovic, B.; Radolic, V.; Varga, M.; Planinic, J.; Vekic, B.

    2006-01-01

    When primary particles from space, mainly protons, enter the atmosphere, they produce interactions with air nuclei, and cosmic-ray showers are induced. The radiation field at aircraft altitude is complex, with different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard A 320 and ATR 42 aircraft was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter; the neutron dose was measured with the neutron dosimeter consisted of LR-115 track detector and boron foil BN-1 or 10B converter. The estimated occupational effective dose for the aircraft crew (A320) working 500 h per year was 1.64 mSv. Another experiment was performed at the flights Zagreb - Paris - Buenos Aires and reversely, when one measured cosmic radiation dose; for 26.7 h of flight, the MINI 6100 dosimeter gave an average dose rate of 2.3 μSv/h and the TLD dosimeter registered the total dose of 75 μSv or the average dose rate of 2.7 μSv/h; the neutron dosimeter gave the dose rate of 2.4 μSv/h. In the same month, February 2005, a traveling to the Japan (24 hours-flight: Zagreb - Frankfurt - Tokyo and reversely) and the TLD-100 measurement showed the average dose rate of 2.4 μSv/h; the neutron dosimeter gave the dose rate of 2.5 μSv/h. Comparing dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level, we could conclude the neutron component curried about 50% of the total dose, that was near other known data. (author)

  13. Occupational radiation dose in Indonesia 1981-1986

    International Nuclear Information System (INIS)

    Hiswara, E.; Ismono, A.

    1993-01-01

    Occupational radiation dose in Indonesia 1981-1986. This paper presents the occupational radiation dose in Indonesia during the period of 1981-1986. The highest collective dose accurated in 1983 was calculated to be 2.68 man-Sv, with the maximum mean dose per worker, who received dose more than zero, was around 11.07 mSv in the same year. In 1985, a relative collective dose from medical occupations of 1.88 man mSv for 10 6 population was estimated based on its total collective dose of 0.31 man-mSv. The total number of workers who received annual collective dose less than 5 mSv varied from 97.0% in 1981 to 99.5% in 1986. As a group, the industrial occupations has considerably higher risk in receiving a dose than others. (authors). 11 refs., 7 tabs

  14. Ionizing and ultraviolet radiation enhances the efficiency of DNA mediated gene transfer in vitro

    International Nuclear Information System (INIS)

    Perez, C.F.

    1984-08-01

    The enhancement effects of ionizing and non-ionizing radiation on the efficiency of DNA mediated gene transfer were studied. Confluent Rat-2 cells were transfected with purified SV40 viral DNA, irradiated with either X-rays or ultraviolet, trypsinized, plated, and assayed for the formation of foci on Rat-2 monolayers. Both ionizing and ultraviolet radiation enhanced the frequency of A-gene transformants/survivor compared to unirradiated transfected cells. These enhancements were non-linear and dose dependent. A recombinant plasmid, pOT-TK5, was constructed that contained the SV40 virus A-gene and the Herpes Simplex virus (HSV) thymidine kinase (TK) gene. Confluent Rat-2 cells transfected with pOT-TK5 DNA and then immediately irradiated with either X-rays or 330 MeV/amu argon particles at the Berkeley Bevalac showed a higher frequency of HAT + colonies/survivor than unirradiated transfected cells. Rat-2 cells transfected with the plasmid, pTK2, containing only the HSV TK-gene were enhanced for TK-transformation by both X-rays and ultraviolet radiation. The results demonstrate that radiation enhancement of the efficiency of DNA mediated gene transfer is not explained by increased nuclear uptake of the transfected DNA. Radiation increases the competence of the transfected cell population for genetic transformation. Three models for this increased competence are presented. The targeted integration model, the inducible recombination model, the partition model, and the utilization of DNA mediated gene transfer for DNA repair studies are discussed. 465 references

  15. Ionizing and ultraviolet radiation enhances the efficiency of DNA mediated gene transfer in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Perez, C.F.

    1984-08-01

    The enhancement effects of ionizing and non-ionizing radiation on the efficiency of DNA mediated gene transfer were studied. Confluent Rat-2 cells were transfected with purified SV40 viral DNA, irradiated with either X-rays or ultraviolet, trypsinized, plated, and assayed for the formation of foci on Rat-2 monolayers. Both ionizing and ultraviolet radiation enhanced the frequency of A-gene transformants/survivor compared to unirradiated transfected cells. These enhancements were non-linear and dose dependent. A recombinant plasmid, pOT-TK5, was constructed that contained the SV40 virus A-gene and the Herpes Simplex virus (HSV) thymidine kinase (TK) gene. Confluent Rat-2 cells transfected with pOT-TK5 DNA and then immediately irradiated with either X-rays or 330 MeV/amu argon particles at the Berkeley Bevalac showed a higher frequency of HAT/sup +/ colonies/survivor than unirradiated transfected cells. Rat-2 cells transfected with the plasmid, pTK2, containing only the HSV TK-gene were enhanced for TK-transformation by both X-rays and ultraviolet radiation. The results demonstrate that radiation enhancement of the efficiency of DNA mediated gene transfer is not explained by increased nuclear uptake of the transfected DNA. Radiation increases the competence of the transfected cell population for genetic transformation. Three models for this increased competence are presented. The targeted integration model, the inducible recombination model, the partition model, and the utilization of DNA mediated gene transfer for DNA repair studies are discussed. 465 references.

  16. Ambient radiation dose reduction within a newly remodeled Nuclear Medicine Department

    International Nuclear Information System (INIS)

    Lai, Y.C.; Chen, Y.W.; Huang, Y.F.

    2008-01-01

    Full text: Ambient radiation levels at the patient waiting areas have been greatly reduced after remodeling of our Nuclear Medicine Department (NMD) based on the ALARA consideration. Complete ambient radiation monitoring of our NMD before remodeling had been characterized and published earlier by the same authors elsewhere. The NMD outpatients, with an initial dose of up to 740 MBq (20 mCi) per case, may wait around and incidentally congest in one place that could cause an unexpected higher exposure level in public access areas. In this new surveillance study after remodeling, the ambient radiation time-profile, peak dose rates and daily doses have been re-evaluated by using high sensitivity, digital survey dosimeters. As a preliminary result, with our newly improved facility in operation, we have demonstrated the NMD waiting room average daily dose has dropped from about 3.0 μSv to 0.42 μSv during most of busy days in comparison. The hourly peak dose rate detected in patient waiting areas has also reduced to a factor of more than two, from maximum dose rate of 40.4 μSv/h to 15.4 μSv/h, during one worst case scenario. The great reduction of the environment dose was achieved mainly by using larger room space with thicker lead wall, from previous 2-mm to new 5-mm in lead thickness, and by increasing patient waiting rooms/areas with less chairs available in each seating location. Other NMD administrative control measure of our dose reduction program has also been emphasized in better patient routing, scheduling and less waiting time for the diagnostic patients. (author)

  17. Estimation of radiation dose received by the radiation worker during 18F FDG injection process

    International Nuclear Information System (INIS)

    Jha, Ashish Kumar; Zade, Anand; Rangarajan, Venkatesh

    2011-01-01

    The radiation dosimetric literature concerning the medical and non-medical personnel working in nuclear medicine departments are limited, particularly radiation doses received by radiation worker in nuclear medicine department during positron emission tomography (PET) radiopharmaceutical injection process. This is of interest and concern for the personnel. To measure the radiation dose received by the staff involved in injection process of Fluorine-18 Fluorodeoxyglucose (FDG). The effective whole body doses to the radiation workers involved in injections of 1511 patients over a period of 10 weeks were evaluated using pocket dosimeter. Each patient was injected with 5 MBq/kg of 18 F FDG. The 18 F-FDG injection protocol followed in our department is as follows. The technologist dispenses the dose to be injected and records the pre-injection activity. The nursing staff members then secure an intravenous catheter. The nuclear medicine physicians/residents inject the dose on a rotation basis in accordance with ALARA principle. After the injection of the tracer, the nursing staff members flush the intravenous catheter. The person who injected the tracer then measures the post-injection residual dose in the syringe. The mean effective whole body doses per injection for the staff were the following: Nurses received 1.44 ± 0.22 μSv/injection (3.71 ± 0.48 nSv/MBq), for doctors the dose values were 2.44 ± 0.25 μSv/injection (6.29 ± 0.49 nSv/MBq) and for technologists the doses were 0.61 ± 0.10 μSv/injection (1.58 ± 0.21 nSv/MBq). It was seen that the mean effective whole body dose per injection of our positron emission tomography/computed tomography (PET/CT) staff who were involved in the 18 F-FDG injection process was maximum for doctors (54.34% differential doses), followed by nurses (32.02% differential doses) and technologist (13.64% differential doses). This study confirms that low levels of radiation dose are received by staff during 18 F-FDG injection and

  18. The use of radiation and the other radiation practices in 1992

    International Nuclear Information System (INIS)

    Havukainen, R.

    1993-05-01

    In the end of the year 1992 there were in force 1630 safety licenses for the use of radiation granted by the Finnish Centre for Radiation and Nuclear Safety (STUK). In addition to this there were 2022 places for dental x-ray activities in Finland. All together 12468 radiation sources and 308 radioisotope laboratories were in use. The import of radioactive substances was 3.9 x 10 15 Bq and the export 2.6 x 10 13 Bq. The production of short-lived isotopes was 1.1 x 10 13 Bq. The monitoring of personal radiation doses were organized for 11978 workers and 1286 working places. The annual dose (the integrated readings of dosemeters) was greater than registration threshold for 23 % of workers. The collective dose (the sum of the results of the dose measurements) registered to the Finnish Dose Register was 7.6 manSv; 78 % belonged to the workers of nuclear power plants. The sum of the personal doses measured in 1992 were for eight radiologists or interventional radiologists and eight workers in nuclear power plants 20 mSv or more. The effective doses were in each case under the annual dose limit of 50 mSv. The effective doses for the radiologists and interventional radiologists were under 20 mSv. It was reported to STUK eight failures or exceptional events. The reasons for these events were usually human mistakes or neglects. (editor)

  19. Radiation exposure around patients after 201Tl-myocardial scintigraphy

    International Nuclear Information System (INIS)

    Kurtaran, A.; Preitfellner, J.; Kohoutek, D.; Tousek, A.; Virgolini, I.; Havlik, E.

    1997-01-01

    Aim: It was the aim of the study to assess the additional radiation exposure to patients, attendents and nurses by patients who are undergoing nuclear medicine investigations (myocardial scintigraphy) with 201 Tl-chloride ( 201 Tl-Cl). Methode: In 16 cases the dose rates at 0.5, 1 and 2 m distance from patients were measured at 0.5, 1.5, 3-4 and 24, in some cases until 370 h after administration of 100±10 MBq 201 Tl-Cl. From the time courses of the dose rates around the patients the possible radiation exposure of other persons were estimated. Results: The initial values of the dose rate were 3.82 μSv/h at 0.5 m, 1.18 μSv/h at 1 m and 0.30 μSv/h at 2 m distance from the patients respectively. The dose rates were decreasing following a monoexponential course with an effective half-life of 60 h. The maximum doses to other persons at 1 m distance from the patients were determined by considering three scenarios. The values were 13 μSv in the waiting room, 26 μSv for nurses working in the ward and 105 μSv for persons living in the same household. Conclusion: Even at very restrictive assumptions the doses were far below the maximum permissible dose to non-radiation workers set by radiation protection regulations (1.5 mSv per year). (orig.) [de

  20. Maintenance hemodialysis patients have high cumulative radiation exposure.

    LENUS (Irish Health Repository)

    Kinsella, Sinead M

    2010-10-01

    Hemodialysis is associated with an increased risk of neoplasms which may result, at least in part, from exposure to ionizing radiation associated with frequent radiographic procedures. In order to estimate the average radiation exposure of those on hemodialysis, we conducted a retrospective study of 100 patients in a university-based dialysis unit followed for a median of 3.4 years. The number and type of radiological procedures were obtained from a central radiology database, and the cumulative effective radiation dose was calculated using standardized, procedure-specific radiation levels. The median annual radiation dose was 6.9 millisieverts (mSv) per patient-year. However, 14 patients had an annual cumulative effective radiation dose over 20 mSv, the upper averaged annual limit for occupational exposure. The median total cumulative effective radiation dose per patient over the study period was 21.7 mSv, in which 13 patients had a total cumulative effective radiation dose over 75 mSv, a value reported to be associated with a 7% increased risk of cancer-related mortality. Two-thirds of the total cumulative effective radiation dose was due to CT scanning. The average radiation exposure was significantly associated with the cause of end-stage renal disease, history of ischemic heart disease, transplant waitlist status, number of in-patient hospital days over follow-up, and death during the study period. These results highlight the substantial exposure to ionizing radiation in hemodialysis patients.

  1. The analysis of radiation levels for daily supplies made in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.R. [Ulsan National Inst. of Science and Tech., Ulsan (Korea, Republic of)

    2014-07-01

    The radiation levels were measured and assessed for samples around a living environment such as building materials and industrial products for which civil complaint had been filed to have radioactivity in Korea. The dose rates for more than one hundred samples from the goods in a living environment were compared with those of the background. The sample's radiation level ranged from 0.095 μSv/h to 0.162 μSv/h, which are within the range of the laboratory background level from 0.090 μSv/h to 0.174 μSv/h. It was thought the radiation level of the goods for which the civil complaint was given had not particular difference from the environmental radiation level in Korea in spite of deviations for some samples. (author)

  2. Flight attendant radiation dose from solar particle events.

    Science.gov (United States)

    Anderson, Jeri L; Mertens, Christopher J; Grajewski, Barbara; Luo, Lian; Tseng, Chih-Yu; Cassinelli, Rick T

    2014-08-01

    Research has suggested that work as a flight attendant may be related to increased risk for reproductive health effects. Air cabin exposures that may influence reproductive health include radiation dose from galactic cosmic radiation and solar particle events. This paper describes the assessment of radiation dose accrued during solar particle events as part of a reproductive health study of flight attendants. Solar storm data were obtained from the National Oceanic and Atmospheric Administration Space Weather Prediction Center list of solar proton events affecting the Earth environment to ascertain storms relevant to the two study periods (1992-1996 and 1999-2001). Radiation dose from exposure to solar energetic particles was estimated using the NAIRAS model in conjunction with galactic cosmic radiation dose calculated using the CARI-6P computer program. Seven solar particle events were determined to have potential for significant radiation exposure, two in the first study period and five in the second study period, and over-lapped with 24,807 flight segments. Absorbed (and effective) flight segment doses averaged 6.5 μGy (18 μSv) and 3.1 μGy (8.3 μSv) for the first and second study periods, respectively. Maximum doses were as high as 440 μGy (1.2 mSv) and 20 flight segments had doses greater than 190 μGy (0.5 mSv). During solar particle events, a pregnant flight attendant could potentially exceed the equivalent dose limit to the conceptus of 0.5 mSv in a month recommended by the National Council on Radiation Protection and Measurements.

  3. Shutdown dose rates at ITER equatorial ports considering radiation cross-talk from torus cryopump lower port

    Energy Technology Data Exchange (ETDEWEB)

    Juárez, Rafael, E-mail: rjuarez@ind.uned.es [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain); Pampin, Raul [F4E, Torres Diagonal Litoral B3, Josep Pla 2, Barcelona 08019 (Spain); Levesy, Bruno [ITER Organization, 13115 Route de Vinon sur Verdon, St Paul Lez Durance (France); Moro, Fabio [ENEA, Via Enrico Fermi 45, Frascati, Rome (Italy); Suarez, Alejandro [ITER Organization, 13115 Route de Vinon sur Verdon, St Paul Lez Durance (France); Sanz, Javier [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain)

    2015-11-15

    Shutdown dose rates for planned maintenance purposes is an active research field in ITER. In this work the radiation (neutron and gamma) cross-talk between ports in the most conservative case foreseen in ITER is investigated: the presence of a torus cryopump lower port, mostly empty for pumping efficiency reasons. There will be six of those ports: #4, #6, #10, #12, #16 and #18. The equatorial ports placed above them will receive a significant amount of additional radiation affecting the shutdown dose rates during in situ maintenance activities inside the cryostat, and particularly in the port interspace area. In this study a general situation to all the equatorial ports placed above torus cryopump lower ports is considered: a generic diagnostics equatorial port placed above the torus cryopump lower port (LP#4). In terms of shutdown dose rates at equatorial port interspace after 10{sup 6} s of cooling time, 405 μSv/h has been obtained, of which 160 μSv/h (40%) are exclusively due to radiation cross-talk from a torus cryopump lower port. Equatorial port activation due to only “local neutrons” contributes 166 μSv/h at port interspace, showing that radiation cross-talk from such a lower port is a phenomenon comparable in magnitude to the neutron leakage though the equatorial port plug.

  4. The Dose Response Relationship for Radiation Carcinogenesis

    Science.gov (United States)

    Hall, Eric

    2008-03-01

    Recent surveys show that the collective population radiation dose from medical procedures in the U.S. has increased by 750% in the past two decades. It would be impossible to imagine the practice of medicine today without diagnostic and therapeutic radiology, but nevertheless the widespread and rapidly increasing use of a modality which is a known human carcinogen is a cause for concern. To assess the magnitude of the problem it is necessary to establish the shape of the dose response relationship for radiation carcinogenesis. Information on radiation carcinogenesis comes from the A-bomb survivors, from occupationally exposed individuals and from radiotherapy patients. The A-bomb survivor data indicates a linear relationship between dose and the risk of solid cancers up to a dose of about 2.5 Sv. The lowest dose at which there is a significant excess cancer risk is debatable, but it would appear to be between 40 and 100 mSv. Data from the occupation exposure of nuclear workers shows an excess cancer risk at an average dose of 19.4 mSv. At the other end of the dose scale, data on second cancers in radiotherapy patients indicates that cancer risk does not continue to rise as a linear function of dose, but tends towards a plateau of 40 to 60 Gy, delivered in a fractionated regime. These data can be used to estimate the impact of diagnostic radiology at the low dose end of the dose response relationship, and the impact of new radiotherapy modalities at the high end of the dose response relationship. In the case of diagnostic radiology about 90% of the collective population dose comes from procedures (principally CT scans) which involve doses at which there is credible evidence of an excess cancer incidence. While the risk to the individual is small and justified in a symptomatic patient, the same is not true of some screening procedures is asymptomatic individuals, and in any case the huge number of procedures must add up to a potential public health problem. In the

  5. β-radiation exposure with 188Re-labelled pharmaceuticals

    International Nuclear Information System (INIS)

    Andreeff, M.; Wunderlich, G.; Kotzerke, J.; Behge, K.; Schoenmuth, Th.

    2005-01-01

    Aim: The number of therapies with radiopharmaceuticals labelled with 188 Re is increasing requiring the documentation of the beta radiation exposure Hp(0.07) of the staff at all working and production sites and during the application and follow-up of the patient according to the new German Radiation Protection Law (StrlSchV). However, data for β-radiation exposure are rare. Therefore, we determined the personal dose Hp(0.07) of the skin of the hands handling 188 Re radiopharmaceuticals to identify steps of high radiation exposure and to optimize working conditions. Method: Thermoluminescence dosimeters (TLD 100) were fixed to the fingertips of the radiochemist, the physician and the nurse and compared to official ring dosimeters. In addition, to monitor radiation exposure continuously readable electronic beta- and gamma dosimeters EPD (Siemens) were used. At eight days in which therapies were performed these readings were evaluated. Results: Considering one therapy with a 188 Re-labelled radiopharmaceutical the middle finger of the radiochemist (production) and the physician (application) showed a radiation burden of 894 and 664 μSv/GBq, respectively. The cumulative dose of the fingertips after eight days of therapy was 249 and 110 mSv for the radiochemist and physician, respectively. A cumulative finger dose after eight days of therapy of 17 and 39 μSv/GBq was found for physician and nurse leading to a Hp(0.07) of 3 and 6 mSv, respectively. Preparing the radiopharmaceutical labelled with 20 GBq of 188 Re the reading of the personal electronic dosimeter of the radiochemist showed a γ-dose rate Hp(10) of 55 μSv/h and a β-dose rate Hp(0.07) of 663 μSv/h which are obviously not representative for the true radiation dose to the skin of the fingertips. Conclusion: During therapy with 188 Re-labelled radiopharmaceuticals the true radiation dose to the skin of the finger tips exceeds by far the readings of the official ring dosimeters as well as the continuously

  6. Optimization of radiation protection (OPR) of workers in nuclear medicine department occupationally to ionizing radiation

    International Nuclear Information System (INIS)

    Ugrinska, Ana; Crcareva, Biljana; Andonovski, Boris

    2010-01-01

    Occupational radiation exposure of nuclear medicine personnel arise either from external irradiation during the handling or from the entry of radioactive substances in the body; the major source of external irradiation is the patient that has received a radiopharmaceutical for diagnostic or therapeutic purposes. In this study we present the dosimetry monitoring of the personnel at the Institute of Pathophysiology and Nuclear Medicine in Skopje (IPNM) before and after the implementation the methods of ORP. Twenty-seven employees were optimized with standard TLD card, monthly, expressed as whole body personal dose in the period of use of dosimeter. Annual Effective Doses (AED) are presented for years: 2001, 2004, 2005, 2006, 2007, 2008. In the year 2005, after measurement from Technical Service Organization, IPNM Radiation Protection Officer (RPO) designed and implemented new recommendation and modality such as: designation of areas, introducing ambiental dose measurements, classification of employees, personnel rotation, risk assessment, occupational dose constraints, education of personnel, compliance with written procedures and establishing the Programme for Radiation Protection (RP). ORP measures were applied during the year of 2006, so the results of 2001, 2004 and 2005 correspond to unopimized RP. We were evaluated three groups: radiopharmacy laboratory (RPL), nuclear medicine technologist (NMT) and medical doctors. The third group was further divided according to the AED in group with AED bellow 1.6 mSv (MD1), and group with AED above this level (MD2). The average AED in the NMT group for 2005 was 3.59 mSv, while in 2008 it was 1.8 mSv; for MD1 group in 2005 was 1.5 mSv and in MD2 was 3.0 mSv. The average AED in 2008 for MD1 was 1.1 mSv, while MD2 group comprised of only one subject with annual effective dose of 1.76 mSv. The most exposed groups were nuclear medicine technologists (NMT) and medical doctors routinely involved in everyday nuclear medicine

  7. Exposure to background radiation in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S.B. [Australian Radiation Lab., Melbourne, VIC (Australia)

    1997-12-31

    The average effective dose received by the Australian population is estimated to be {approx}1.8 mSv / year. One half of this exposure arises from exposure from terrestrial radiation and cosmic rays, the remainder from radionuclides within the body and from inhalation of radon progeny. This paper reviews a number of research programmes carried out by the Australian Radiation Laboratory to study radiation exposure from natural background, particularly in the workplace and illustrate approaches to the quantification and management of exposure to natural radiation. The average radiation doses to the Australian population are relatively low; the average annual radon concentration ranged from 6 Bq m{sup -3} in Queensland to 16 Bq m{sup -3} in the Australian Capital Territory (ACT). Of more importance is the emerging issue of exposure to elevated background radiation in the workplace. Two situation are presented; the radiation exposure to air crues and show cave tour guides. Annual doses up to 3.8 mSv were estimated for international crew members while the highest estimate for show cave tour guides was 9 mSv per year. 9 refs., 2 tabs., 4 figs.

  8. Human population exposure to cosmic radiation

    International Nuclear Information System (INIS)

    Bouville, A.; Lowder, W.M.

    1988-01-01

    Critical evaluations of existing data on cosmic radiation in the atmosphere and in interplanetary space have been carried out in order to estimate the exposure of the world's population to this important component of natural background radiation. Data on population distribution and mean terrain heights on a 1 x 1 degree grid have been folded in to estimate regional and global dose distributions. The per caput annual dose equivalent at ground altitudes is estimated to be 270 μSv from charged particles and 50 μSv from neutrons. More than 100 million people receive more than 1 mSv in a year, and two million in excess of 5 mSv. Aircraft flight crews and frequent flyers receive an additional annual dose equivalent in the order of 1 mSv, though the global per caput annual dose equivalent from airplane flights is only about 1 μSv. Future space travellers on extended missions are likely to receive dose equivalents in the range 0.11 Sv, with the possibility of higher doses at relatively high dose rates from unusually large solar flares. These results indicate a critical need for a better understanding of the biological significance of chronic neutron and heavy charged particle exposure. (author)

  9. Calmodulin-activated cyclic nucleotide phosphodiesterase from brain. Relationship of subunit structure to activity assessed by radiation inactivation

    International Nuclear Information System (INIS)

    Kincaid, R.L.; Kemdner, E.; Manganiello, V.C.; Osborne, J.C.; Vaughan, M.

    1981-01-01

    The apparent target sizes of the basal and calmodulin-dependent activities of calmodulin-activated phosphodiesterase from bovine brain were estimated using target theory analysis of data from radiation inactivation experiments. Whether crude or highly purified samples were irradiated, the following results were obtained. Low doses of radiation caused a 10 to 15% increase in basal activity, which, with further irradiation, decayed with an apparent target size of approx.60,000 daltons. Calmodulin-dependent activity decayed with an apparent target size of approx.105,000 daltons. The percentage stimulation of enzyme activity by calmodulin decreased markedly as a function of radiation dosage. These observations are consistent with results predicted by computer-assisted modeling based on the assumptions that: 1) the calmodulin-activated phosphodiesterase exists as a mixture of monomers which are fully active in the absence of calmodulin and dimers which are inactive in the absence of calmodulin; 2) in the presence of calmodulin, a dimer exhibits activity equal to that of two monomers; 3) on radiation destruction of a dimer, an active monomer is generated. This monomer-dimer hypothesis provides a plausible explanation for and definition of basal and calmodulin-dependent phosphodiesterase activity

  10. SV-AUTOPILOT: optimized, automated construction of structural variation discovery and benchmarking pipelines.

    Science.gov (United States)

    Leung, Wai Yi; Marschall, Tobias; Paudel, Yogesh; Falquet, Laurent; Mei, Hailiang; Schönhuth, Alexander; Maoz Moss, Tiffanie Yael

    2015-03-25

    Many tools exist to predict structural variants (SVs), utilizing a variety of algorithms. However, they have largely been developed and tested on human germline or somatic (e.g. cancer) variation. It seems appropriate to exploit this wealth of technology available for humans also for other species. Objectives of this work included: a) Creating an automated, standardized pipeline for SV prediction. b) Identifying the best tool(s) for SV prediction through benchmarking. c) Providing a statistically sound method for merging SV calls. The SV-AUTOPILOT meta-tool platform is an automated pipeline for standardization of SV prediction and SV tool development in paired-end next-generation sequencing (NGS) analysis. SV-AUTOPILOT comes in the form of a virtual machine, which includes all datasets, tools and algorithms presented here. The virtual machine easily allows one to add, replace and update genomes, SV callers and post-processing routines and therefore provides an easy, out-of-the-box environment for complex SV discovery tasks. SV-AUTOPILOT was used to make a direct comparison between 7 popular SV tools on the Arabidopsis thaliana genome using the Landsberg (Ler) ecotype as a standardized dataset. Recall and precision measurements suggest that Pindel and Clever were the most adaptable to this dataset across all size ranges while Delly performed well for SVs larger than 250 nucleotides. A novel, statistically-sound merging process, which can control the false discovery rate, reduced the false positive rate on the Arabidopsis benchmark dataset used here by >60%. SV-AUTOPILOT provides a meta-tool platform for future SV tool development and the benchmarking of tools on other genomes using a standardized pipeline. It optimizes detection of SVs in non-human genomes using statistically robust merging. The benchmarking in this study has demonstrated the power of 7 different SV tools for analyzing different size classes and types of structural variants. The optional merge

  11. New candidate tumor-suppressor gene KLF6 and its splice variant KLF6 SV2 counterbalancing expression in primary hepatocarcinoma.

    Science.gov (United States)

    Zhenzhen, Zhou; De'an, Tian; Limin, Xia; Wei, Yan; Min, Luo

    2012-01-01

    This study aimed to detect the expression of newly discovered zinc finger transcriptional factor KLF6 and its splice variant KLF6 SV2 in primary hepatocarcinoma (PHC) tissues and hepatoma cell strains, and to evaluate their clinicopathologic relationship with PHC. Wild-type KLF6 and KLF6 SV2 mRNA expression was determined by RTPCR in 27 cases of PHC tissues and cell strains of HepG2, SMMC7721 and LO2. Western blotting and immunohistochemical staining were adopted to detect KLF6 protein expression. Positive area ratio of wild-type KLF6 protein expression and its relationship with clinicopathological parameters of PHC was analyzed. Wild-type KLF6 expression in PHC tissues was lower than that in paracancerous tissues. In contrast, KLF6 SV2 mRNA expression was higher in PHC tissues and hepatoma cell strains (p<0.05). Positive area ratio of wild-type KLF6 protein expression was positively correlated with cellular differentiation degree of PHC (p<0.01), but negatively correlated not only with liver cirrhosis, tumor size and extrahepatic metastases (p<0.01), but also with portal vein thrombus and the number of lymph nodes with metastasis (p<0.05). Wild-type KLF6 deletion and inactivation was involved in the growth, cell differentiation and other physiological processes of PHC. The upregulation of KLF6 splice variant might counterbalance the wildtype KLF6 and contribute to the occurrence and development of PHC.

  12. Radiation exposure during CT-guided biopsies: recent CT machines provide markedly lower doses.

    Science.gov (United States)

    Guberina, Nika; Forsting, Michael; Ringelstein, Adrian; Suntharalingam, Saravanabavaan; Nassenstein, Kai; Theysohn, Jens; Wetter, Axel

    2018-03-28

    To examine radiation dose levels of CT-guided interventional procedures of chest, abdomen, spine and extremities on different CT-scanner generations at a large multicentre institute. 1,219 CT-guided interventional biopsies of different organ regions ((A) abdomen (n=516), (B) chest (n=528), (C) spine (n=134) and (D) extremities (n=41)) on different CT-scanners ((I) SOMATOM-Definition-AS+, (II) Volume-Zoom, (III) Emotion6) were included from 2013-2016. Important CT-parameters and standard dose-descriptors were retrospectively examined. Additionally, effective dose and organ doses were calculated using Monte-Carlo simulation, following ICRP103. Overall, radiation doses for CT interventions are highly dependent on CT-scanner generation: the newer the CT scanner, the lower the radiation dose imparted to patients. Mean effective doses for each of four procedures on available scanners are: (A) (I) 9.3mSv versus (II) 13.9mSv (B) (I) 7.3mSv versus (III) 11.4mSv (C) (I) 6.3mSv versus (II) 7.4mSv (D) (I) 4.3mSv versus (II) 10.8mSv. Standard dose descriptors [standard deviation (SD); CT dose index vol (CTDI vol ); dose-length product (DLP body ); size-specific dose estimate (SSDE)] were also compared. Effective dose, organ doses and SSDE for various CT-guided interventional biopsies on different CT-scanner generations following recommendations of the ICRP103 are provided. New CT-scanner generations involve markedly lower radiation doses versus older devices. • Effective dose, organ dose and SSDE are provided for CT-guided interventional examinations. • These data allow identifying organs at risk of higher radiation dose. • Detailed knowledge of radiation dose may contribute to a better individual risk-stratification. • New CT-scanner generations involve markedly lower radiation doses compared to older devices.

  13. Radiation exposure and radiation protection of the physician in iodine-131 Lipiodol therapy of liver tumours

    International Nuclear Information System (INIS)

    Risse, J.H.; Ponath, C.; Palmedo, H.; Biersack, H.J.; Menzel, C.; Gruenwald, F.

    2001-01-01

    Intra-arterial iodine-131 labelled Lipiodol therapy for liver cancer has been investigated for safety and efficacy over a number of years, but data on radiation exposure of personnel have remained unavailable to date. The aim of this study was to assess the radiation exposure of the physician during intra-arterial 131 I-Lipiodol therapy for liver malignancies and to develop appropriate radiation protection measures and equipment. During 20 intra-arterial administrations of 131 I-Lipiodol (1110-1924 MBq), radiation dose equivalents (RDE) to the whole body, fingers and eyes of the physician were determined for (a) conventional manual administration through a shielded syringe, (b) administration with an automatic injector and (c) administration with a lead container developed in-house. Administration by syringe resulted in a finger RDE of 19.5 mSv, an eye RDE of 130-140 μSv, and a whole-body RDE of 108-119 μSv. The injector reduced the finger RDE to 5 mSv. With both technique (a) and technique (b), contamination of angiography materials was observed. The container allowed safe transport and administration of the radiopharmaceutical from 4 m distance and reduced the finger RDE to 131 I-Lipiodol was administered by syringe or injector, but was significantly reduced with the lead container. (orig.)

  14. Use of radiation and radiation practices 1994. Events and statistics

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.

    1995-05-01

    In Finland, there were 1,745 valid safety licences for the use of radiation at the end of 1994. In addition, 2,050 sites were included in the compulsory registration for dental x-ray diagnostics. The register of the Finnish Centre for Radiation and Nuclear Safety listed 12,794 radiation sources and 316 radionuclide laboratories. The import of radioactive substances amounted to 4.6x10{sup 15} Bq and export to 2.2x10{sup 13} Bq. A total of 1.4x10{sup 13} Bq of short-lived radionuclides were produced in Finland. Workers monitored for radiation exposure included 11,147 employees on 1,294 work sites. Of these, 27% received an annual dose exceeding the recording threshold. The total dose recorded in the dose register (sum of personal dosemeter readings) was 75 man Sv in 1994, nuclear power plant employees accounting for 70% of this total. The annual dosemeter reading of ten medical doctors (radiologists, international radiologists and cardiologists) and five nuclear power plant employees was equal to or in excess of 20 mSv. Effective dose, however, did not exceed the dose limit of 50 mSv established for a one-year monitoring period.

  15. Investigation of Contributions of Cosmic Radiation to Background Dose with Altitude at Ahmadu Bello University, Zaria, Nigeria

    International Nuclear Information System (INIS)

    Uwaechia, F.C.; Zakari, Y.I.; Ibeanu, I.G.E.

    2014-01-01

    This study investigated the contributions of cosmic radiation to background dose at Ahmadu Bello University, Zaria, Nigeria using two portable survey meters (Rados -120 and FH 40F2 ). The work was conducted in two phases (dry and rainy seasons).The recorded gamma dose rates were observed to proportionally increase with increase in altitude, that is from ground floor (altitude 3.52 m above sea level) to the eight floor (altitude 30.08 m above sea level). In a similar manner, there were observed variations in the seasonal results-the dry season data were consistently higher than the rainy season data. The mean measured indoor and outdoor gamma dose rates for the two seasons (rainy and dry seasons) were 210.0nSv/h and 279.4nSv/h, and 231.3nSv/h and 368.8nSv/h at the ground floor and the eight floor, respectively. The rainy season result repeated itself on a particular very heavy rainy day with a mean measured gamma dose rate of 204.4nSv/h and 267.4nSv/h at the ground floor and eight floor, respectively. The annual indoor and outdoor mean effective dose for a 1000hour working period was calculated as 0.32 μSv and 0.35 μSv at the ground floor and 0.68 μSv and 0.76 μSv the 8 th floor, respectively (for inside and outside the building).

  16. Space Radiation Dosimetry

    International Nuclear Information System (INIS)

    Deme, S.

    2003-01-01

    Although partly protected from galactic and solar cosmic radiation by the Earth's magnetosphere in Low Earth Orbit (LEO) astronauts exposure levels during long-term missions (90 days to 180 days) by far exceed with exposures of up to more than 100 mSv the annual exposure limits set for workers in the nuclear industry, but are still below the yearly exposure limits of 500 mSv for NASA astronauts. During solar particle events the short-term limits (300 mSv) may be approached or even exceeded. In the interplanetary space, outside the Earth's magnetic field even relatively benign Solar Particle Events (SPEs) can produce 1 Sv skin-absorbed doses. Although new rocket technologies could reduce astronauts' total exposure to space radiation during a human Mars mission, the time required for the mission, which is now in the order of years. Therefore mission planners will need to consider a variety of countermeasures for the crew members including physical protection (e.g. shelters), active protection (e.g. magnetic protection), pharmacological protection, local protection (extra protection for critical areas of the body) etc. With full knowledge of these facts, accurate personal dose measurement will become increasingly important during human missions to Mars. The new dose limits for radiation workers correspond to excess lifetime risk of 3% (NCRP) and 4% (ICRP). While astronauts accept the whole variety of flight risks they are taking in mission, there is concern about risks that may occur later in life. A risk no greater than the risk of radiation workers would be acceptable. (author)

  17. Investigation of environmental natural penetrating radiation level in Hebei province

    International Nuclear Information System (INIS)

    Zheng Deliang; Wang Shuming; Yang Huanfeng

    1990-01-01

    The methods and results of the investigation on natural penetrating radiation level in Hebei Province from 1985 to 1987 are presented. 285 25 x 25 km-netted measuring points were set unformly up all over the porvince, with 204 densely measuring points of different types added. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate for field is 5.59, 5.51 and 5.31 x 10 -8 Gy·h -1 , respectively; (2) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 3.05 and 2.80 x 10 -8 Gy·h -1 , and outside buildings is 3.38 and 3.11 x 10 -8 Gy·h -1 , respectively; (3) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 12.44 and 11.97 x 10 -8 Gy·h -1 , outside buildings is 8.97 and 8.42 x 10 -8 Gy·h -1 , respectively; (4) The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.50, 0.25, and 0.75 mSv, respectively; and correspondingly, the annual collective effectiv dose equivalent is 2.7, 1.3 and 4.0 x 10 4 man·Sv, respectively

  18. Natural radiation - a perspective to radiological risk factors of nuclear energy production

    DEFF Research Database (Denmark)

    Mustonen, R.; Christensen, T.; Stranden, E.

    1992-01-01

    Radiation doses from natural radiation and from man-made modifications on natural radiation, and different natural radiological environments in the Nordic countries are summarized and used as a perspective for the radiological consequences of nuclear energy production. The significance of different...... radiation sources can be judged against the total collective effective dose equivalent from natural radiation in the Nordic countries, 92 000 manSv per year. The collective dose from nuclear energy production during normal operation is estimated to 20 manSv per year and from non-nuclear energy production...... to 80 manSv per year. The increase in collective dose due to the conservation of heating energy in Nordic dwellings is estimated to 23 000 manSv per year, from 1973 to 1984. An indirect radiological danger index is defined in order to be able to compare the significance of estimated future releases...

  19. Assessment of occupational radiation exposure in underground artisanal gold mines in Tongo, Upper East Region of Ghana

    International Nuclear Information System (INIS)

    Doyi, I.; Oppon, O.C.; Glover, E.T.; Gbeddy, G.; Kokroko, W.

    2013-01-01

    Assessments of radon and gamma radiation levels were carried out in underground artisanal gold mines in Tongo. This is one of the numerous artisanal gold mining communities in Ghana. Solid State Nuclear Track Detectors (SSNTDs) were used to estimate the mean 222 Rn concentration and dose rates during the Harmattan season (November 2010 to February 2011). The values for the 222 Rn concentration at each monitoring site ranged from 14 ± 4 Bq m −3 to 270 ± 9 Bq m −3 , with a mean value of 98 Bq m −3 . These measurements are well below the lower action level of 500 Bq m −3 recommended by ICRP for workplaces. The activity concentrations of 40 K, 232 Th and 238 U were determined using gamma-ray spectroscopy method. The effective dose estimates of 0.11 ± 0.02 mSv y −1 to 0.68 ± 0.04 mSv y −1 were below the allowable limit of 20 mSv per annum for occupational exposure control recommended by the ICRP. The total annual effective dose varied from 0.22 ± 0.04 mSv y −1 to 1.92 ± 0.08 mSv y −1 . -- Highlights: • Mean radon concentration ranged from 14 ± 4 Bq m −3 to 270 ± 9 Bq m −3 . • Annual effective dose of radionuclides from 0.11 ± 0.02 to 0.69 ± 0.04 mSv y −1 . • 238 U, 232 Th and 40 K contributed 5–20%, 39–78% and 17–49% of effective dose. • Max total annual effective dose of 1.9 ± 0.08 mSv y −1 below 20 mSv y −1 set by ICRP 60

  20. Correlation among the terrestrial gamma radiation, the indoor air 222Rn, and the tap water 222Rn in Switzerland

    International Nuclear Information System (INIS)

    Buchli, R.; Burkart, W.

    1989-01-01

    The external gamma radiation and the indoor air Rn (222Rn) concentration were measured in 55 houses of the South East Grisons, the Urseren valley, and the Upper Rhine valley (crystalline subsoils) and in 39 houses of the Molasse basin and the Helvetic nappes (sedimentary subsoils). In homes located on a crystalline subsoil, a mean cellar gamma level of 1.40 mGy y-1 was measured, which is twice the mean gamma level of 0.70 mGy y-1 found in homes built on a sedimentary subsoil. The cellar 222Rn gas concentration is about six times higher in houses with a crystalline subsoil (1232 Bq m-3) than in houses with a sedimentary subsoil (201 Bq m-3). Although a weak correlation is observed between the mean gamma radiation levels and mean cellar 222Rn gas concentrations for the five subregions investigated, the gamma levels and the 222Rn gas concentrations do not correlate for single homes. For the population living on the ground floor of a house with a crystalline subsoil, the gamma radiation and the indoor air 222Rn lead to estimated mean exposures of 1.16 mSv and 9.44 mSv effective dose equivalent per year, respectively. In houses with a sedimentary subsoil, these mean exposures lead to 0.68 mSv y-1 and 3.22 mSv y-1, respectively. A mean tap water 222Rn content of 38.3 Bq L-1 and 10.4 Bq L-1 was measured in 31 villages with a crystalline subsoil and 73 villages with a sedimentary subsoil, respectively. Radon-222 degasing from the tap water into the indoor air leads to an additional exposure of about 0.11 mSv y-1 and 0.03 mSv y-1 in homes with a crystalline subsoil and homes with a sedimentary subsoil, respectively

  1. Size of the plasma membrane H+-ATPase from Neurospora crassa determined by radiation inactivation and comparison with the sarcoplasmic reticulum Ca2+-ATPase from skeletal muscle

    International Nuclear Information System (INIS)

    Bowman, B.J.; Berenski, C.J.; Jung, C.Y.

    1985-01-01

    Using radiation inactivation, the authors have measured the size of the H + -ATPase in Neurospora crassa plasma membranes. Membranes were exposed to either high energy electrons from a Van de Graaff generator or to gamma irradiation from 60 Co. Both forms of radiation caused an exponential loss of ATPase activity in parallel with the physical destruction of the Mr = 104,000 polypeptide of which this enzyme is composed. By applying target theory, the size of the H + -ATPase in situ was found to be approximately 2.3 X 10(5) daltons. They also used radiation inactivation to measure the size of the Ca 2+ -ATPase of sarcoplasmic reticulum and got a value of approximately 2.4 X 10(5) daltons, in agreement with previous reports. By irradiating a mixture of Neurospora plasma membranes and rabbit sarcoplasmic reticulum, they directly compared the sizes of these two ATPases and found them to be essentially the same. The authors conclude that both H + -ATPase and Ca 2+ -ATPase are oligomeric enzymes, most likely composed of two approximately 100,000-dalton polypeptides

  2. Association between simian virus 40 and non-Hodgkin lymphoma

    Science.gov (United States)

    Vilchez, Regis A.; Madden, Charles R.; Kozinetz, Claudia A.; Halvorson, Steven J.; White, Zoe S.; Jorgensen, Jeffrey L.; Finch, Chris J.; Butel, Janet S.

    2002-01-01

    BACKGROUND: Non-Hodgkin lymphoma has increased in frequency over the past 30 years, and is a common cancer in HIV-1-infected patients. Although no definite risk factors have emerged, a viral cause has been postulated. Polyomaviruses are known to infect human beings and to induce tumours in laboratory animals. We aimed to identify which one of the three polyomaviruses able to infect human beings (simian virus 40 [SV40], JC virus, and BK virus) was associated with non-Hodgkin lymphoma. METHODS: We analysed systemic non-Hodgkin lymphoma from 76 HIV-1-infected and 78 HIV-1-uninfected patients, and non-malignant lymphoid samples from 79 HIV-1-positive and 107 HIV-1-negative patients without tumours; 54 colon and breast carcinoma samples served as cancer controls. We used PCR followed by Southern blot hybridisation and DNA sequence analysis to detect DNAs of polyomaviruses and herpesviruses. FINDINGS: Polyomavirus T antigen sequences, all of which were SV40-specific, were detected in 64 (42%) of 154 non-Hodgkin lymphomas, none of 186 non-malignant lymphoid samples, and none of 54 control cancers. This difference was similar for HIV-1-infected patients and HIV-1-uninfected patients alike. Few tumours were positive for both SV40 and Epstein-Barr virus. Human herpesvirus type 8 was not detected. SV40 sequences were found most frequently in diffuse large B-cell and follicular-type lymphomas. INTERPRETATION: SV40 is significantly associated with some types of non-Hodgkin lymphoma. These results add lymphomas to the types of human cancers associated with SV40.

  3. Current radiation exposure of man: a comparison between digital imaging and environmental, workplace and accidental radiation burden

    International Nuclear Information System (INIS)

    Regulla, Dieter; Hoeschen, Christoph; Wahl, Wolfgang

    2008-01-01

    X-ray imaging in diagnostic radiology is recognized worldwide as an outstanding tool for the early recognition and prevention of diseases. The reverse side is that radiography contributes essentially to the exposure of the public. Mean effective doses, averaged over patients and non-patients, are reaching or exceeding the level of natural radiation. This is particularly the case when digital imaging techniques are utilized, such as CT, coronary angiography and interventional radiology. Individual effective doses for a patient may occur between several mSv and several hundred mSv by one examination or a series of examinations, while individual organ doses of a patient may reach equivalent doses even up to several Sv, such as for the skin. The purpose of this review is to provide information on effective dose levels occurring in diagnostic radiology as compared with individual effective doses achieved from environmental radiation, radiation at workplaces and after major radiation incidents. (author)

  4. Study of the radiation levels in low dose rate brachytherapy zones of the National Institute of Neoplastic Illnesses

    International Nuclear Information System (INIS)

    Figueroa J, N.; Mora Y, B.

    2006-01-01

    The present study has as objective to evaluate the radiation levels of the Brachytherapy work areas of low dose rate (Gammateque, nurses station and of hospitalization rooms of patients RIC of 4th, 5th Floor-East) and to estimate the effective dose of the occupationally exposed personnel and the public in general. The measurements of the dose rate in these areas, were registered with a radiations monitor Inspector trademark, during a period of 60 days, without altering the routinary work conditions. The more high levels of environmental dose equivalent rate registered in the different work areas its are of 1.41 and 47.78 μSv/h rooms 1 and 2 in the Gammateque environments, in the hospitalization rooms of the 4th and 5th floor in the point 1 are of 40.77 and 23.67, μSv/h respectively and in the point 2 are of 129.19 and 39.93, μSv/h respectively, and in the nurses station of the 4th and 5th floor its are respectively of 7.62 u Sv/h and 0.45 u Sv/h. According to the carried out measurements and the permanency in the work place is possible to estimate the effective dose involved to the occupationally exposed personnel. The personnel that works in Gammateque could be receiving respectively as maximum dose 0.61 mSv/month, and the personnel that works in the nurses station of 13.17 and 0.78 mSv/year in the 4th and 5th floor. These registered differences among the two floors are due to that the 5th floor counts with the shielding systems (screen) contrary to the 4th, another of the factors is the distribution form of the patient beds RIC. We should have present that the radiation levels although in some cases it is very high, however, they are below of the permissible limits according to standards, but it is still possible to reduce even more, the radiation levels in the critical points fulfilling with the ALARA principle. (Author)

  5. Fast neutron radiation inactivation of Bacillus subtilis: Absorbed dose determination

    International Nuclear Information System (INIS)

    Song Lingli; Zheng Chun; Ai Zihui; Li Junjie; Dai Shaofeng

    2011-01-01

    In this paper, fast neutron inactivation effects of Bacillus subtilis were investigated with fission fast neutrons from CFBR-II reactor of INPC (Institute of Nuclear Physics and Chemistry) and mono-energetic neutrons from the Van de Graaff accelerator at Peking University. The method for determining the absorbed dose in the Bacillus subtilis suspension contained in test tubes is introduced. The absorbed dose, on account of its dependence on the volume and the form of confined state, was determined by combined experiments and Monte Carlo method. Using the calculation results of absorbed dose, the fast neutron inactivation effects on Bacillus subtilis were studied. The survival rates and absorbed dose curve was constructed. (authors)

  6. Doses from Medical Radiation Sources

    Science.gov (United States)

    ... Medical Radiation Sources Michael G. Stabin, PhD, CHP Introduction Radiation exposures from diagnostic medical examinations are generally ... of exposure annually to natural background radiation. Plain Film X Rays Single Radiographs Effective Dose, mSv Skull ( ...

  7. Analysis of dose record and epidemiology for radiation workers in Korea

    International Nuclear Information System (INIS)

    Choi, S.Y.; Kim, T.H.

    2003-01-01

    This study presents data on the externally received doses and preliminary results of epidemiological survey for radiation workers. The statistical analysis was carried out in order to understand better the occupational radiation doses in Korea. Records containing dose information from 1984 to 1999 for 64,518 persons were extracted from the National Dose Registry of Korea (Korea Radioisotope Association's personal dose record). The total number of workers registered from 1984 to 1999 was 64,518. The number of workers steadily increased and the accumulated dose somewhat increased. The proportion of radiation workers by occupation was 38.4% for nuclear power plant, 20.3% for industrial organization and 12.4% for non-destructive industry, respectively. The collective annual dose of radiation workers was 31.72 man Sv in 1999. The mean annual dose by sex was 1.49 mSv for male and 0.56 mSv for female. The mean annual dose for workers was 1.41 mSv with the highest mean dose being received by non-destructive industry (3.53 mSv). Very few workers(0.8%) received more than 20 mSv and only one more than 50 mSv, the legal limit for an annual dose. There has been a steady decline in the mean dose since 1984, showing a significant decrease in dose with time. The data showed that radiation protection in Korea was improving, though annual doses were still higher than other countries. Nevertheless, this finding brings to light the necessity of the workers to pay more careful attention to radiation protection procedures and practices, and suggest the need for continuous effort to implement procedures. We are carrying out epidemiological survey in order to evaluate radiation effects on Korean workers based on radiation dose data from the year of 2000. Follow-up is carrying out in order to detect and measure directly the risks of cancer using the Korean Mortality Data, Cancer Registry and individual investigation

  8. Radiation survey of aircraft and heavy machinery scrap

    International Nuclear Information System (INIS)

    Idriss, Hajo; Salih, Isam; Gumaa, Elsadig; Yassin, Abbas; Yousif, E.H.; Abdel Hamid, Saad Eldeen M.; Sam, A.K.

    2012-01-01

    This study was conducted primarily to survey aircraft and heavy machinery at 30 locations within Khartoum State using handheld radiation survey meters to detect and identify any radiation sources that might be present and to estimate radiation dose levels. The survey has resulted in detection of 16 sealed sources of 90 Sr and one of 226 Ra in aircraft scrap. Of course, 90 Sr sources are used in military aircraft as temperature sensors while 226 Ra is used for indicating fuel levels. These sources were found intact without spreading radioactivity contamination; however, none was detected in heavy machine scrap. The levels of radiation dose measured at 0.1 m from the source fall within the range of 25.1–40.2 μSv/h with an average value of 33.52±4.06 μSv/h. These orphan sources have been separated from the scrap, tested for possible leakage, conditioned and stored in waste management facility. The result of this study has revealed without doubt that the scrap constitute a serious source of public exposure and highlights the importance of legislation making radiation monitoring of scrap in the country mandatory before it is sold to metal industry for reprocessing. - Highlights: ► Sealed radioactive sources ( 90 Sr and 226 Ra) were detected in aircraft scrap. ► No source was detected in heavy machine scrap. ► Radiation dose measured at 0.1 m from the source can be used to estimate exposure to public. ► Monitoring of scrap was found to be useful for protection (from orphan sources).

  9. Preirradiation of host (monkey) cells mitigates the effects of UV upon simian virus 40 DNA replication

    International Nuclear Information System (INIS)

    Scaria, A.; Edenberg, H.J.

    1987-01-01

    The authors examined the effects of preirradiation of host (monkey) cells upon the replication of UV-damaged SV40. Control cells and cells preirradiated with low fluences of UV were infected with undamaged SV40, and the immediate effects of a subsequent irradiation were determined. UV inhibited total SV40 DNA synthesis in both preirradiated and control cells, but the extent of inhibition was less in the preirradiated cells. A test fluence of 60 J/m 2 to SV40 replicating in preirradiated cells reduced synthesis only as much as a test fluence of 25 J/m 2 in control cells. The fraction of recently replicated SV40 molecules that re-entered the replication pool and subsequently completed one round of replication in the first 2 h after UV was also decreased less in the preirradiated cells. Thus preirradiation of the host cell mitigates the immediate inhibitory effects of a subsequent UV exposure upon SV40 replication. (Auth.)

  10. The Evaluation of personnel radiation dose and society radiation on RSG-GAS around as proposal determination of ALARA value

    International Nuclear Information System (INIS)

    Pande Made Udiyani; Puradwi IW

    2007-01-01

    Each nuclear installation to achieve radiation safety has to meet the ALARA concepts. The ALARA value of a nuclear installation should be enacted by regulator body. ALARA value can be determined by evaluation radiation exposure and dose acceptance of nuclear installation operation. As case study in Indonesia, ALARA assessment in nuclear installation is done at RSG-GAS reactor. Intention of this research is to determine gyration reference assess ALARA by evaluate radiation dose acceptance by RSG-GAS radiation personnel and the influence of RSG-GAS operation to presentation of radiation accepted by society which living around its. ALARA of RSG-GAS determined based on evaluation of measurement data of the radiation doses which is accepted by personnel radiation. While evaluation of radiation doses which is accepted by society in the radius 5 km of the RSG-GAS conducted to data result of calculation using program package of CAP-88 and measurement result with method of carborne survey. Result of radiation dose evaluation obtained which not pass dose definition for the radiation worker that is 50 mSv/year, and for society around RSG-GAS that is 5 mSv/year. Based on the result of evaluation hence obtained value of ALARA for RSG-GAS in value of gyration 17 - 50 mSv/year. (author)

  11. Exposure to cosmic radiation: a developing major problem in radiation protection

    International Nuclear Information System (INIS)

    Lowder, W.M.; Hajnal, F.

    1992-01-01

    'Full Text:' Cosmic radiation at ground altitudes is usually a relatively minor contributor to human radiation exposure, producing a global collective dose equivalent that is about 10 percent of the total from all natural sources. However, more than a million people living at high altitudes receive annual dose equivalents in excess of 5 mSv. In recent years, there has been increasing concern about the exposure of aircraft flight crews and passengers, for whom annual dose equivalents of up to several mSv have been estimated. Recent EML results indicate the presence of an important high-energy neutron component at jet aircraft altitudes, perhaps producing dose equivalents of the order of 0.1. mSv/h at high latitudes. Finally, space agencies have been long concerned with the potential exposures of astronauts, especially from the rare massive solar flare events. As more people venture into space, this source of human radiation exposure will become increasingly important. Available date on those aspects of cosmic radiation exposure will be reviewed, along with current and anticipated future research activities that may yield and improve assessment of the problem. The question of how such exposures might be controlled will be addressed, but not answered. (author)

  12. C-arm flat-panel CT arthrography of the shoulder: Radiation dose considerations and preliminary data on diagnostic performance

    International Nuclear Information System (INIS)

    Guggenberger, Roman; Ulbrich, Erika J.; Kaelin, Pascal; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav; Dietrich, Tobias J.; Scholz, Rosemarie; Koehler, Christoph; Elsaesser, Thilo; Le Corroller, Thomas

    2017-01-01

    To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard. Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated. Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between κ = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies. Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT. (orig.)

  13. C-arm flat-panel CT arthrography of the shoulder: Radiation dose considerations and preliminary data on diagnostic performance

    Energy Technology Data Exchange (ETDEWEB)

    Guggenberger, Roman; Ulbrich, Erika J.; Kaelin, Pascal; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zuerich (Switzerland); Dietrich, Tobias J. [Balgrist University Hospital, Department of Radiology, Zurich (Switzerland); Scholz, Rosemarie; Koehler, Christoph; Elsaesser, Thilo [Siemens Healthcare GmbH, Business Area Advanced Therapies, Forchheim (Germany); Le Corroller, Thomas [Aix-Marseille Universite, CNRS, ISM UMR 7287, Marseille (France); Radiology Department, APHM, Marseille (France)

    2017-02-15

    To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard. Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated. Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between κ = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies. Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT. (orig.)

  14. Annual dose distribution of Nuclear Malaysia radiation workers for monitoring period from year 2003 to 2007

    International Nuclear Information System (INIS)

    Hairul Nizam Idris; Azimawati Ahmad; Norain Ab Rahman

    2008-08-01

    Estimation of radiation dose (external exposure) received by Nuklear Malaysia's radiation workers are measured by using personal dosimetry device which are provided by SSDL-Nuklear Malaysia. Dose assessment report for monitoring period from year 2003 - 2007 shows that almost all radiation workers received annual doses less than 20 mSv, only in very small percentage of radiation workers received annual doses between 20.1 to 50 mSv and none of the workers received doses higher than 50 mSv/year. Exposure dose below 20 mSv/year (the new annual dose limit to be used in Malaysia soon) could be fully achieved by improving the compliance with the safety regulations and enhancing the awareness about radiation safety among the workers. (Author)

  15. Workers radiation protection. Occupational exposure to ionizing radiations in France: 2016 results

    International Nuclear Information System (INIS)

    2017-06-01

    National results of the individual monitoring of occupational exposure to ionizing radiation are reported for all civilian and military activities subject to authorization or declaration (i.e. medical and veterinary activities, nuclear industry, defence, non-nuclear industry and research), as well as for activities concerned by the enhanced exposure to natural radiation. 372 262 workers within activities subject to authorization or declaration were monitored by passive dosimetry in 2015, which represents an increase by 1.8 % compared to 2015. The average individual dose in 2016 was very close to the value in 2015. Furthermore, 14 218 workers received more than 1 mSv (i.e. the legal dose limit for the public), and 2 703 workers received more than 5 mSv. 1 worker received more than 20 mSv (i.e. the dose limit for the workers in the French regulation). As a result, the collective dose increased from 61.9 to 63.2 man.Sv (2 %), thus reaching the same level as in the years 2009 to 2013. Important differences are noticed according to the occupational activities: the average dose in the medical and veterinary field (which represents 61.2 % of the monitored workers) and that in the research field (3.1 % of the monitored workers) are less than 0.35 mSv; the average doses are higher in the nuclear field and in the non-nuclear industry (representing together 30.5 % of the monitored workers), respectively 1.15 mSv and 1.36 mSv. Concerning internal dosimetry, 279 659 individual examinations have been performed in 2016, 54 % of which are radio-toxicological analysis of excreta and 46 % are direct body counting. In 2016, 5 workers had a committed effective dose greater than or equal to 1 mSv and the maximum dose was 19.4 mSv. Data or trends relative to workers exposed to natural radioactivity are also dealt with in this report (air-crews, personnel subjected to radon exposure). In particular, results of aircrew dosimetry are reported: in 2016, the average individual dose of 19 875

  16. Workers radiation protection. Occupational exposure to ionizing radiations in France: 2015 results

    International Nuclear Information System (INIS)

    2016-06-01

    National results of the individual monitoring of occupational exposure to ionizing radiation are reported for all civilian and military activities subject to authorization or declaration (i.e. medical and veterinary activities, nuclear industry, defence, non-nuclear industry and research), as well as for activities concerned by the enhanced exposure to natural radiation. 365 830 workers within activities subject to authorization or declaration were monitored by passive dosimetry in 2015, which represents an increase by 1.7 % compared to 2014. The average individual dose in 2015 was very close to the value in 2014. Furthermore, 14 138 workers received more than 1 mSv (i.e. the legal dose limit for the public), and 2 606 workers received more than 5 mSv. 2 workers received more than 20 mSv (i.e. the dose limit for the workers in the French regulation). As a result, the collective dose increased from 56.3 to 61.9 man.Sv (10 %), thus reaching the same level as in the years 2009 to 2013. Important differences are noticed according to the occupational activities: the average dose in the medical and veterinary field (which represents 62.4 % of the monitored workers) and that in the research field (3.6 % of the monitored workers) are less than 0.4 mSv; the average doses are higher in the nuclear field and in the non-nuclear industry (representing together 30.1 % of the monitored workers), respectively 1.17 mSv and 1.38 mSv. Concerning internal dosimetry, 279 877 individual examinations have been performed in 2015, 52 % of which are radio-toxicological analysis of excreta and 48 % are direct body counting. In 2015, 2 workers had a committed effective dose greater than or equal to 1 mSv and the maximum dose was 3 mSv. Data or trends relative to workers exposed to natural radioactivity are also dealt with in this report (air crews, personnel subjected to radon exposure). In particular, results of aircrew dosimetry are reported: in 2015, the average individual dose of 19 565

  17. Measurement and evaluation of personal radiation dose during 18F-FDG PET imaging

    International Nuclear Information System (INIS)

    Lu Ning; Wang Jing; Qiao Hongqing; Deng Jinglan; Li Guoquan; Zhou Yi

    2004-01-01

    Objective: To measure and evaluate the personal radiation dose for medical staff and patient accompanying persons in PET imaging, in order to offer the reference data for clinical radiation protection. Methods: Analysis of γ-ray radiation dose rate was performed on 30 medical staff members by using radiation dose meter during each medical procedure in injection room and scanning room , and the instantaneous, 1 and 2 h dose rate at 0.1, 0.5, 1.0 and 2.0 m from the mid-thorax of the patient received injection of the isotope were also measured. Then the mean dose per medical procedure per person and the assuming annual dose at different working sites were all calculated. Results: The mean personal doses per procedure were: left hand (30.0 ± 8.0) μSv, right hand (6.0 ± 1.5) μSv, whole-body (0.5 ± 0.1) μSv for syringe preparation; hand (3.00 ± 0.75) μSv, whole-body (1.27 ± 0.20) μSv for injection; (9.9 ± 1.4) μSv for imaging operation; (310 ± 91) μSv for close contact accompanying persons. Annual dose for staff members working in different sites were: left hand (16.63 ± 4.41) mSv, right hand (6.45 ± 1.23) mSv, whole-body (1.18 ± 0.15) mSv in the injection room; whole-body (4.99 ± 0.70) mSv in the imaging room. Conclusion: Under the normal operational conditions, the dose received by staff members and accompanying persons do not exceed the annual limit for professional and non-professional persons that has published as GuoBiao safe standard (GBSS)

  18. Inactivation kinetics of Escherichia coli O157:H7, Salmonella enterica Serovar Typhimurium, and Listeria monocytogenes in ready-to-eat sliced ham by near-infrared heating at different radiation intensities.

    Science.gov (United States)

    Ha, Jae-Won; Kang, Dong-Hyun

    2014-07-01

    The aim of this study was to investigate the inactivation kinetics of Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes on ready-to-eat sliced ham by near-infrared (NIR) heating as a function of the processing parameter, radiation intensity. Precooked ham slices inoculated with the three pathogens were treated at different NIR intensities (ca. 100, 150, and 200 μW/cm(2)/nm). An increase in the applied radiation intensity resulted in a gradual increase of inactivation of all pathogens. The survival curves of the three pathogens exhibited both shoulder and tailing behavior at all light intensities. Among nonlinear models, the Weibull distribution and log-logistic model were used to describe the experimental data, and the statistical results (mean square error and R(2) values) indicated the suitability of the model for prediction. The log-logistic model more accurately described survival curves of the three pathogens than did the Weibull distribution at all radiation intensities. The output of this study and the proposed kinetics model would be beneficial to the deli meat industry for selecting the optimum processing conditions of NIR heating to meet the target pathogen inactivation on ready-to-eat sliced ham.

  19. Benefits of adopting good radiation practices in reducing the whole body radiation dose to the nuclear medicine personnel during (18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Verma, Shashwat; Kheruka, Subhash Chand; Maurya, Anil Kumar; Kumar, Narvesh; Gambhir, Sanjay; Kumari, Sarita

    2016-01-01

    Positron emission tomography has been established as an important imaging modality in the management of patients, especially in oncology. The higher gamma radiation energy of positron-emitting isotopes poses an additional radiation safety problem. Those working with this modality may likely to receive higher whole body doses than those working only in conventional nuclear medicine. The radiation exposure to the personnel occurs in dispensing the dose, administration of activity, patient positioning, and while removing the intravenous (i.v.) cannula. The estimation of radiation dose to Nuclear Medicine Physician (NMP) involved during administration of activity to the patient and technical staff assisting in these procedures in a positron emission tomography/computed tomography (PET/CT) facility was carried out. An i.v access was secured for the patient by putting the cannula and blood sugar was monitored. The activity was then dispensed and measured in the dose calibrator and administered to the patient by NMP. Personnel doses received by NMP and technical staff were measured using electronic pocket dosimeter. The radiation exposure levels at various working locations were assessed with the help of gamma survey meter. The radiation level at working distance while administering the radioactivity was found to be 106-170 μSv/h with a mean value of 126.5 ± 14.88 μSv/h which was reduced to 4.2-14.2 μSv/h with a mean value of 7.16 ± 2.29 μSv/h with introduction of L-bench for administration of radioactivity. This shows a mean exposure level reduction of 94.45 ± 1.03%. The radiation level at working distance, while removing the i.v. cannula postscanning was found to be 25-70 μSv/h with a mean value of 37.4 ± 13.16 μSv/h which was reduced to 1.0-5.0 μSv/h with a mean value of 2.77 ± 1.3 μSv/h with introduction of L-bench for removal of i.v cannula. This shows a mean exposure level reduction of 92.85 ± 1.78%. This study shows that good radiation practices are

  20. Inactivation of viruses by pasteurization at 60 °C for 10 h with and without 40% glucose as stabilizer during a new manufacturing process of α2-Macroglobulin from Cohn Fraction IV.

    Science.gov (United States)

    Huangfu, Chaoji; Ma, Yuyuan; Jia, Junting; Lv, Maomin; Zhu, Fengxuan; Ma, Xiaowei; Zhao, Xiong; Zhang, Jingang

    2017-03-01

    Pasteurization is regularly used to inactivate viruses for the safety of plasma derivatives. Influence of pasteurization at 60 °C for 10 h on α2-Macroglobulin activity and virus inactivation were studied. With 40% sugar as stabilizers more than 70% α2-Macroglobulin activity was reserved after pasteurization compared with 20% in control. Glucose presented a better activity protection effect than sucrose and maltose. By pasteurization without stabilizer the virus titers of pseudorabies virus, Sindbis virus, porcine parvovirus and encephalomyocarditis virus were reduced more than 5.88 log 10 , 7.50 log 10 , 4.88 log 10 , and 5.63 log 10 respectively within 2 h. By pasteurization with 40% glucose vesicular stomatitis virus was inactivated more than 5.88 log 10 within 1 h. Only 2.71 log 10 reduction was achieved for encephalomyocarditis virus after 10 h. 40% glucose protected α2-M activity and viruses simultaneously from pasteurization. Other viral inactivation methods need to be incorporated to ensure viral safety of this manufacturing process of α2-Macroglobulin. Copyright © 2017 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  1. Implementation of radiation protection programme in industrial radiography centers in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Deevband, M. [Radiation Protection Department, Tehran (Iran, Islamic Republic of); Ghiassi Negad, M. [Radiation Protection Department, Tehran (Iran, Islamic Republic of); Borhan Azad, S. [Radiation Protection Department, Tehran (Iran, Islamic Republic of); Tavakoli, M. [Esfahan Univ. (Iran, Islamic Republic of)

    2006-07-01

    Industrial radiography is one of the essential methods in the modern technology to guarantee the quality control of many types of devices, pieces and machines operation, and usually involves intense radiation sources, which can expose people at work to significant amounts of radiation. According to the reports of United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR 2000), the average occupational effective dose in this field is 3.37 mSv/y. The level of dose received by industrial radiographers was assessed in more than 1300 radiation workers in 120 industrial radiography companies. The level of radiation safety regulations and radiation protection programme implemented in Iranian industries was also studied. The results indicated that the average effective dose to the radiographers and collective effective dose are 1.65 mSv/y and 2.43 Man.Sv respectively. The results also showed that 88% of radiographers have received less than 5 mSv/y and only 1% received the annual dose more than 20 mSv. The lack of emergency instruction was found in 47% of companies and in 35% of companies there was not found any compatible emergency instrument. Suitable temporary storage and transportation facility was no also found in 30% of companies. Based on the results found in this study, the enforcement of the radiation protection low and industrial radiography code of practice for responsible persons and health physics officers are recommended. (authors)

  2. Implementation of radiation protection programme in industrial radiography centers in Iran

    International Nuclear Information System (INIS)

    Deevband, M.; Ghiassi Negad, M.; Borhan Azad, S.; Tavakoli, M.

    2006-01-01

    Industrial radiography is one of the essential methods in the modern technology to guarantee the quality control of many types of devices, pieces and machines operation, and usually involves intense radiation sources, which can expose people at work to significant amounts of radiation. According to the reports of United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR 2000), the average occupational effective dose in this field is 3.37 mSv/y. The level of dose received by industrial radiographers was assessed in more than 1300 radiation workers in 120 industrial radiography companies. The level of radiation safety regulations and radiation protection programme implemented in Iranian industries was also studied. The results indicated that the average effective dose to the radiographers and collective effective dose are 1.65 mSv/y and 2.43 Man.Sv respectively. The results also showed that 88% of radiographers have received less than 5 mSv/y and only 1% received the annual dose more than 20 mSv. The lack of emergency instruction was found in 47% of companies and in 35% of companies there was not found any compatible emergency instrument. Suitable temporary storage and transportation facility was no also found in 30% of companies. Based on the results found in this study, the enforcement of the radiation protection low and industrial radiography code of practice for responsible persons and health physics officers are recommended. (authors)

  3. Stimulation of NADH-dependent microsomal DNA strand cleavage by rifamycin SV.

    Science.gov (United States)

    Kukiełka, E; Cederbaum, A I

    1995-04-15

    Rifamycin SV is an antibiotic anti-bacterial agent used in the treatment of tuberculosis. This drug can autoxidize, especially in the presence of metals, and generate reactive oxygen species. A previous study indicated that rifamycin SV can increase NADH-dependent microsomal production of reactive oxygen species. The current study evaluated the ability of rifamycin SV to interact with iron and increase microsomal production of hydroxyl radical, as detected by conversion of supercoiled plasmid DNA into the relaxed open circular state. The plasmid used was pBluescript II KS(-), and the forms of DNA were separated by agarose-gel electrophoresis. Incubation of rat liver microsomes with plasmid plus NADH plus ferric-ATP caused DNA strand cleavage. The addition of rifamycin SV produced a time- and concentration-dependent increase in DNA-strand cleavage. No stimulation by rifamycin SV occurred in the absence of microsomes, NADH or ferric-ATP. Stimulation occurred with other ferric complexes besides ferric-ATP, e.g. ferric-histidine, ferric-citrate, ferric-EDTA, and ferric-(NH4)2SO4. Rifamycin SV did not significantly increase the high rates of DNA strand cleavage found with NADPH as the microsomal reductant. The stimulation of NADH-dependent microsomal DNA strand cleavage was completely blocked by catalase, superoxide dismutase, GSH and a variety of hydroxyl-radical-scavenging agents, but not by anti-oxidants that prevent microsomal lipid peroxidation. Redox cycling agents, such as menadione and paraquat, in contrast with rifamycin SV, stimulated the NADPH-dependent reaction; menadione and rifamycin SV were superior to paraquat in stimulating the NADH-dependent reaction. These results indicate that rifamycin SV can, in the presence of an iron catalyst, increase microsomal production of reactive oxygen species which can cause DNA-strand cleavage. In contrast with other redox cycling agents, the stimulation by rifamycin SV is more pronounced with NADH than with NADPH as the

  4. Assessment of environmental 226Ra, 232Th and 40K concentrations in the region of elevated radiation background in Segamat District, Johor, Malaysia

    International Nuclear Information System (INIS)

    Saleh, Muneer Aziz; Ramli, Ahmad Termizi; Alajerami, Yasser; Aliyu, Abubakar Sadiq

    2013-01-01

    Extensive environmental survey and measurements of gamma radioactivity in the soil samples collected from Segamat District were conducted. Two gamma detectors were used for the measurements of background radiation in the area and the results were used in the computation of the mean external radiation dose rate and mean weighted dose rate, which are 276 nGy h −1 and 1.169 mSv y −1 , respectively. A high purity germanium (HPGe) detector was used in the assessment of activity concentrations of 232 Th, 226 Ra and 40 K. The results of the gamma spectrometry range from 11 ± 1 to 1210 ± 41 Bq kg −1 for 232 Th, 12 ± 1 to 968 ± 27 Bq kg −1 for 226 Ra, and 12 ± 2 to 2450 ± 86 Bq kg −1 for 40 K. Gross alpha and gross beta activity concentrations range from 170 ± 50 to 4360 ± 170 Bq kg −1 and 70 ± 20 to 4690 ± 90 Bq kg −1 , respectively. These results were used in the plotting of digital maps (using ARCGIS 9.3) for isodose. The results are compared with values giving in UNSCEAR 2000. -- Highlights: • Assessment of the activities in region of elevated radiation in Segamat District. • The average dose rate found to be six times higher than the world average. • The activity of 232 Th is six times world average. • The activity of 226 Ra is four times and 40 K is lower than world average. • A digital map plotted for isodose

  5. Predialing the number of cinegraphic frames enables an effective patient dose due to coronary angiography of 0.8 mSv

    International Nuclear Information System (INIS)

    Kuon, E.; Schmitt, M.; Dorn, C.; Pfahlberg, A.; Gefeller, O.; Dahm, J.B.

    2003-01-01

    Purpose: To investigate the effect of a new device for predialing the number of cinegraphic frame before each coronary angiography, with the objective of reducing the patient dose area product (DAP) from coronary angiography, which typically requires 1000 to 2350 cinegraphic frames. That DAP is high and stated to be between 15.6 to 106.3 Gy x cm 2 . Applying the accepted DAP-to-ED conversion factors, for the thoracic region of approximately 0.20 mSv/Gy x cm 2 , this corresponds to a mean effective dose (ED) in the range of 3.1 to 21.3 mSv. Material and Methods: For patients undergoing elective coronary angiography, we compared various parameters of radiation exposure obtained with judicious radiation reducing standard techniques (n=106) and with an additional new rotary switch for predialing the number of cinegraphic frames (n=106). Results: The patient radiation dose was significantly lower with the new device, with the mean DAP reduced to 5.5 from 9.1 Gy x cm 2 . The corresponding reducation of the mean DAP for left ventriculography and coronary angiography was 1.3 from 1.7, and 4.2 from 7.4 Gy x cm 2 , respectively. The number of cinegraphic frames was 98 vs. 184, whereas the number of cinegraphic runs and the fluoroscopy time were comparable. Conclusion: Predialing the cinegraphic frame number before each cinegraphic run enables a reduction of the patients effective dose from coronary angiography to 0.8 mSv, i.e. to 57% of the baseline value and far below typically reported values. (orig.) [de

  6. Radiation protection principles for radioiodine therapy

    International Nuclear Information System (INIS)

    Reiners, C.; Lassmann, M.

    1999-01-01

    In Germany, approximately 30,000 treatments with radioiodine are performed yearly on patients with benign or malignant thyroid diseases. These are carried out generally in specialized therapy wards which are equipped with radiation protection facilities. Ambulant (fractionated) radioiodine treatment is not permitted in Germany. More recently, the situation has been that the discharge of patients is permitted, when they have spent a stay of at least 48 hours in the ward without the dose rate exceeding 3.5 μSv/hour at 2 meters distance from them, corresponding to 1 mSv/year (this correlates to a residual activity in the body of the patient of 250 MBq). The radiation exposure of personnel in the therapy ward due to both external and internal exposure lies within a range of a few mSv per year. According to recent studies, the exposure to family members and close friends via external exposure, inhalation or incorporation does not exceed the effective dose of 1 mSv/year. This value has been laid down in a recommendation by the European Union as the dose constraint for children; for adults younger than 60 years of age, 3 mSv are recommended, for older persons 15 mSv. (orig.) [de

  7. Microwave-Irradiation-Assisted HVAC Filtration for Inactivation of Viral Aerosols (Postprint)

    Science.gov (United States)

    2012-02-01

    Baggiani, A. and Senesi, S. (2004). Effect of Microwave Radiation on Bacillus subtilis Spores . J. Appl. Microbiol. 97: 1220–1227. Damit, B., Lee, C.N...AFRL-RX-TY-TP-2012-0020 MICROWAVE-IRRADIATION-ASSISTED HVAC FILTRATION FOR INACTIVATION OF VIRAL AEROSOLS POSTPRINT Myung-Heui Woo and...12-APR-2011 -- 11-DEC-2011 Microwave Irradiation-Assisted HVAC Filtration for Inactivation of Viral Aerosols (POSTPRINT) FA8650-06-C-5913 0602102F

  8. Radiation dose to workers due to the inhalation of dust during granite fabrication

    International Nuclear Information System (INIS)

    Zwack, L M; Stewart, J H; McCarthy, J F; Allen, J G; McCarthy, W B

    2014-01-01

    There has been very little research conducted to determine internal radiation doses resulting from worker exposure to ionising radiation in granite fabrication shops. To address this issue, we estimated the effective radiation dose of granite workers in US fabrication shops who were exposed to the maximum respirable dust and silica concentrations allowed under current US regulations, and also to concentrations reported in the literature. Radiation doses were calculated using standard methods developed by the International Commission on Radiological Protection. The calculated internal doses were very low, and below both US occupational standards (50 mSv yr −1 ) and limits applicable to the general public (1 mSv yr −1 ). Workers exposed to respirable granite dust concentrations at the US Occupational Safety and Health Administration (OSHA) respirable dust permissible exposure limit (PEL) of 5 mg m −3 over a full year had an estimated radiation dose of 0.062 mSv yr −1 . Workers exposed to respirable granite dust concentrations at the OSHA silica PEL and at the American Conference of Governmental Industrial Hygienists Threshold Limit Value for a full year had expected radiation doses of 0.007 mSv yr −1 and 0.002 mSv yr −1 , respectively. Using data from studies of respirable granite dust and silica concentrations measured in granite fabrication shops, we calculated median expected radiation doses that ranged from <0.001 to 0.101 mSv yr −1 . (paper)

  9. Level of natural background radiation and dose to population in Heilongjiang province

    International Nuclear Information System (INIS)

    Liang Yicheng; Wang Lu; He Yongjiang

    1992-01-01

    The natural background radiation in Heilongjiang Province was measured and the population dose was estimated. The results showed that the population-weighted average values of the absorbed dose rate in air from cosmic ray ionization were 3.3 ± 10 -8 Gy·h -1 outdoors and 3.0 x 10 -8 Gy·h -1 indoors. The average values of radon in air were 11.3 Bq·m -3 outdoors and 20.8 Bq·m -3 indoors. The average concentrations of natural radionuclides U, Th, 226 Ra, and 40 K were 6.1 x 10 -2 , 1.1 x 10 -2 , 8.4 x 10 -2 , and 68.9 Bq·kg -1 respectively in food, and 4.8 x 10 -2 , 2.0 x 10 -4 , 1.2 x 10 -2 and 4.6 x 10 -2 Bq·L -1 respectively in drinking water. The total annual individual average effective dose equivalents from natural background radiation were about 2200 μSv. Among them the contributions of cosmic rays, terrestrial radiation, radon and thoron daughters exposure in air, internal exposure within the body were about 320, 630, 860, and 390 μSv, respectively

  10. Replicative intermediates in UV-irradiated Simian virus 40

    International Nuclear Information System (INIS)

    Clark, J.M.; Hanawalt, P.C.

    1984-01-01

    The authors have used Simian virus 40 (SV40) as a probe to study the replication of UV-damaged DNA in mammalian cells. Viral DNA replication in infected monkey kidney cells was synchronized by incubating a mutant of SV40 (tsA58) temperature-sensitive for the initiation of DNA synthesis at the restrictive temperature and then adding aphidicolin to temporarily inhibit DNA synthesis at the permissive temperature while permitting pre-replicative events to occur. After removal of the drug, the infected cells were irradiated at 100 J/m 2 (254 nm) to produce 6-7 pyrimidine dimers per SV40 genome, and returned to the restrictive temperature to prevent reinitiation of replication from the SV40 origin. Replicative intermediates (RI) were labeled with [ 3 H]thymidine. The size distribution of daughter DNA strands in RI isolated shortly after irradiation was skewed towards lengths less than the interdimer spacing in parental DNA; this bias persisted for at least 1 h after irradiation, but disappeared within 3 h by which time the size of the newly-synthesized DNA exceeded the interdimer distance. Evidence was obtained for the generation at late times after irradiation, of Form I molecules in which the daughter DNA strand contain dimers. Thus DNA strand exchange as well as trans-dimer synthesis may be involved in the generation of supercoiled Form I DNA from 0V-damaged SV40 replicative intermediates. (Auth.)

  11. Levels of external natural radiation and doses to population in Heilongjiang province

    International Nuclear Information System (INIS)

    Liang Yicheng; He Yongjiang; Wang Lu

    1985-01-01

    The external natural radiation level in Heilongjiang Province was measured by using China-made FD-71 scintillation radiometers and RSS-111 high pressure ionization chambers. The doses of external radiation to population were also calculated. The population-weighted average value of the absorbed dose rate from terrestrial γ-radiation was 7.2 x 10 -8 Gy.h -1 for outdoors, and 10.8 x 10 -8 Gy.h -1 for indoors. The population-weighted average absorbed dose rate in air from cosmic rays was 3.3 x 10 -8 Gy.h -1 . The annual population-weighted average effective dose equivalent and the annual collective effective dose equivalent from the environmental γ-radiation were 620 μSv and 20.1 x 10 3 man.Sv, respectively. The corresponding figures from cosmic rays were 260 μSv and 8.7 x 10 3 man.Sv, respectively

  12. An influence of occupational exposure on level of chromosome aberrations in nuclear power plant workers

    International Nuclear Information System (INIS)

    Birute Griciene; Grazina Slapsyte

    2007-01-01

    Complete text of publication follows. Objective. The workers of Ignalina Nuclear Power Plant (INPP) receive the highest occupational ionising radiation doses in Lithuania. Their occupational exposure results mainly from external low LET gamma radiation. Some workers receive additional internal and neutron exposure. Though exposure doses are generally low and don't exceed the annual dose limit, the higher doses are obtained during outages. The aim of the present study was to analyse chromosome aberration frequencies in lymphocytes of INPP workers exposed to the different types of ionising radiation. Methods. The blood sampling of 52 INPP male workers was performed in 2004-2006. For 29 workers radiation exposure resulted from the external gamma rays only. Their mean annual dose averaged over the 3-year period prior blood sampling was 11.7±8.7 mSv. The mean cumulative dose - 197.7±174.7 mSv. 15 workers had an intake of gamma radionuclides ( 60 Co, 137 Cs), contributing to the doses less than 0.1 mSv. Their mean cumulative dose - 278.2±191.9 mSv. The mean annual dose averaged over the 3-year period prior blood sampling was 11.8±5.3 mSv. For 8 subjects neutron doses below 0.2 mSv were recorded. Their mean annual dose averaged over the 3-year period prior blood sampling was 7.0±2.9 mSv. The mean cumulative dose was 241.8±93.0 mSv. Heparinized venous blood samples were taken and cultures were initiated according to the standard procedures. Phytohaemagglutinin (7.8 μg/ml) stimulated cultures were incubated at 37degC for 72 hours in RPMI 1640 medium supplemented with 12% heat-inactivated newborn calf serum, 40 μg/ml gentamycin. Colchicine was added to the culture during the initiation at a final concentration of 0,25 μg/ml. The harvested lymphocytes were treated with hypotonic KCl (0,075 M) and then fixed in methanol-glacial acetic acid (3:1). Flame-dried slides were stained with Giemsa, coded and scored blind. Generally 500 first-division cells per individual were

  13. Visible optical radiation generates bactericidal effect applicable for inactivation of health care associated germs demonstrated by inactivation of E. coli and B. subtilis using 405-nm and 460-nm light emitting diodes

    Science.gov (United States)

    Hönes, Katharina; Stangl, Felix; Sift, Michael; Hessling, Martin

    2015-07-01

    The Ulm University of Applied Sciences is investigating a technique using visible optical radiation (405 nm and 460 nm) to inactivate health-hazardous bacteria in water. A conceivable application could be point-of-use disinfection implementations in developing countries for safe drinking water supply. Another possible application field could be to provide sterile water in medical institutions like hospitals or dental surgeries where contaminated pipework or long-term disuse often results in higher germ concentrations. Optical radiation for disinfection is presently mostly used in UV wavelength ranges but the possibility of bacterial inactivation with visible light was so far generally disregarded. One of the advantages of visible light is, that instead of mercury arc lamps, light emitting diodes could be used, which are commercially available and therefore cost-efficient concerning the visible light spectrum. Furthermore they inherit a considerable longer life span than UV-C LEDs and are non-hazardous in contrast to mercury arc lamps. Above all there are specific germs, like Bacillus subtilis, which show an inactivation resistance to UV-C wavelengths. Due to the totally different deactivation mechanism even higher disinfection rates are reached, compared to Escherichia coli as a standard laboratory germ. By 460 nm a reduction of three log-levels appeared with Bacillus subtilis and a half log-level with Escherichia coli both at a dose of about 300 J/cm². By the more efficient wavelength of 405 nm four and a half log-levels are reached with Bacillus subtilis and one and a half log-level with Escherichia coli also both at a dose of about 300 J/cm². In addition the employed optical setup, which delivered a homogeneous illumination and skirts the need of a stirring technique to compensate irregularities, was an important improvement compared to previous published setups. Evaluated by optical simulation in ZEMAX® the designed optical element provided proven

  14. Sunlight inactivation of Escherichia coli in waste stabilization microcosms in a sahelian region (Ouagadougou, Burkina Faso).

    Science.gov (United States)

    Maïga, Ynoussa; Denyigba, Kokou; Wethe, Joseph; Ouattara, Aboubakar Sidiki

    2009-02-09

    Experiments on sunlight inactivation of Escherichia coli were conducted from November 2006 to June 2007 in eight outdoors microcosms with different depths filled with maturation pond wastewater in order to determine pond depth influence on sunlight inactivation of E. coli. The long-term aim was to maximize sunlight inactivation of waterborne pathogens in waste stabilization ponds (WSPs) in sahelian regions where number of sunny days enable longer exposure of wastewater to sunlight. The inactivation was followed during daylight from 8.00 h to 17.00 h and during the night. Sunlight inactivation rates (K(S)), as a function of cumulative global solar radiation (insolation), were 16 and 24 times higher than the corresponding dark inactivation (K(D)) rates, respectively in cold and warm season. In warm season, E. coli was inactivated far more rapidly. Inactivation of E. coli follows the evolution of radiation during the day. In shallow depth microcosms, E. coli was inactivated far more rapidly than in high depth microcosms. The physical chemical parameters [pH, dissolved oxygen (DO)] of microcosms water were higher in shallow depth microcosms than in high depth microcosms suggesting a synergistic effect of sunlight and these parameters to damage E. coli. To increase the efficiency of the elimination of waterborne bacteria, the use of maturation ponds with intermediate depths (0.4m) would be advisable in view of the high temperatures and thus evaporation recorded in sahelian regions.

  15. Radiation monitoring and actions in Finland after reactor accident in Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Paakkola, Olli [Finnish Centre for Radiation and Nuclear Safety, Surveillance Department, Helsinki (Finland)

    1986-07-01

    In the event of a radiation hazard, the authorities participating in radiation control, act in accordance with a guide issued by the Ministry of the Interior. The guide defines the notification and warning limits to be applied between the various bodies. The institutes taking part in radiation control are the Institute of Seismology, the Finnish Meteorological Institute, the Defence Forces, the Ministry of the Interior, and the Finnish Centre for Radiation and Nuclear Safety. The continuously operated radiation monitoring stations of the Defence Forces and the Ministry of the Interior are obliged to notify the other institutes participating in the control if the dose rate of external radiation reaches the value 0.07 mR/h (0,7 microSv/h) and all radiation monitoring stations are obliged to give a warning to the other bodies if the dose rate reaches the value 1 mR/h (10 microSv/h). The Finnish Centre for Radiation and Nuclear Safety has the duty to report exceptional findings and to warn the other institutes as deemed appropriate. According to the guide, population must be warned of a sudden radiation hazard at least when the dose rate has reached the value 200 microSv/h. An alarm for seeking immediate shelter must be given at least when the dose rate exceeds the value 2000 microSv/h.

  16. Radiation monitoring and actions in Finland after reactor accident in Chernobyl

    International Nuclear Information System (INIS)

    Paakkola, Olli

    1986-01-01

    In the event of a radiation hazard, the authorities participating in radiation control, act in accordance with a guide issued by the Ministry of the Interior. The guide defines the notification and warning limits to be applied between the various bodies. The institutes taking part in radiation control are the Institute of Seismology, the Finnish Meteorological Institute, the Defence Forces, the Ministry of the Interior, and the Finnish Centre for Radiation and Nuclear Safety. The continuously operated radiation monitoring stations of the Defence Forces and the Ministry of the Interior are obliged to notify the other institutes participating in the control if the dose rate of external radiation reaches the value 0.07 mR/h (0,7 microSv/h) and all radiation monitoring stations are obliged to give a warning to the other bodies if the dose rate reaches the value 1 mR/h (10 microSv/h). The Finnish Centre for Radiation and Nuclear Safety has the duty to report exceptional findings and to warn the other institutes as deemed appropriate. According to the guide, population must be warned of a sudden radiation hazard at least when the dose rate has reached the value 200 microSv/h. An alarm for seeking immediate shelter must be given at least when the dose rate exceeds the value 2000 microSv/h

  17. Estimated cumulative radiation dose received by diagnostic imaging during staging and treatment of operable Ewing sarcoma 2005-2012

    International Nuclear Information System (INIS)

    Johnsen, Boel; Fasmer, Kristine Eldevik; Boye, Kjetil; Rosendahl, Karen; Aukland, Stein Magnus; Trovik, Clement; Biermann, Martin

    2017-01-01

    Patients with Ewing sarcoma are subject to various diagnostic procedures that incur exposure to ionising radiation. To estimate the radiation doses received from all radiologic and nuclear imaging episodes during diagnosis and treatment, and to determine whether 18 F-fluorodeoxyglucose positron emission tomography - computed tomography ( 18 F-FDG PET-CT) is a major contributor of radiation. Twenty Ewing sarcoma patients diagnosed in Norway in 2005-2012 met the inclusion criteria (age <30 years, operable disease, uncomplicated chemotherapy and surgery, no metastasis or residual disease within a year of diagnosis). Radiation doses from all imaging during the first year were calculated for each patient. The mean estimated cumulative radiation dose for all patients was 34 mSv (range: 6-70), radiography accounting for 3 mSv (range: 0.2-12), CT for 13 mSv (range: 2-28) and nuclear medicine for 18 mSv (range: 2-47). For the patients examined with PET-CT, the mean estimated cumulative effective dose was 38 mSv, of which PET-CT accounted for 14 mSv (37%). There was large variation in number and type of examinations performed and also in estimated cumulative radiation dose. The mean radiation dose for patients examined with PET-CT was 23% higher than for patients not examined with PET-CT. (orig.)

  18. Simian virus 40, poliovirus vaccines, and human cancer: research progress versus media and public interests

    Science.gov (United States)

    Butel, J. S.

    2000-01-01

    From 1955 through early 1963, millions of people were inadvertently exposed to simian virus 40 (SV40) as a contaminant of poliovirus vaccines; the virus had been present in the monkey kidney cultures used to prepare the vaccines and had escaped detection. SV40 was discovered in 1960 and subsequently eliminated from poliovirus vaccines. This article reviews current knowledge about SV40 and considers public responses to reports in the media. SV40 is a potent tumour virus with broad tissue tropism that induces tumours in rodents and transforms cultured cells from many species. It is also an important laboratory model for basic studies of molecular processes in eukaryotic cells and mechanisms of neoplastic transformation. SV40 neutralizing antibodies have been detected in individuals not exposed to contaminated poliovirus vaccines. There have been many reports of detection of SV40 DNA in human tumours, especially mesotheliomas, brain tumours and osteosarcomas; and DNA sequence analyses have ruled out the possibility that the viral DNA in tumours was due to laboratory contamination or that the virus had been misidentified. However, additional studies are necessary to prove that SV40 is the cause of certain human cancers. A recently published review article evaluated the status of the field and received much media attention. The public response emphasized that there is great interest in the possibility of health risks today from vaccinations received in the past.

  19. Radionuclides in cigarettes may lead to carcinogenesis via p16INK4a inactivation

    International Nuclear Information System (INIS)

    Prueitt, Robyn L.; Goodman, Julie E.; Valberg, Peter A.

    2009-01-01

    It is widely accepted that tobacco smoke is responsible for the vast majority of lung cancers worldwide. There are many known and suspected carcinogens present in cigarette smoke, including α-emitting radioisotopes. Epidemiologic studies have shown that increased lung cancer risk is associated with exposure to ionizing radiation, and it is estimated that the majority of smoking-induced lung cancers may be at least partly attributable to the inhaled and deposited radiation dose from radioisotopes in the cigarette smoke itself. Recent research shows that silencing of the tumor suppressor gene p16 INK4a (p16) by promoter methylation plays a role in smoking-related lung cancer. Inactivation of p16 has also been associated with lung cancer incidence in radiation-exposed workers, suggesting that radionuclides in cigarette smoke may be acting with other compounds to cause smoking-induced lung cancer. We evaluated the mechanism of ionizing radiation as an accepted cause of lung cancer in terms of its dose from tobacco smoke and silencing of p16. Because both radiation and cigarette smoking are associated with inactivation of p16, and p16 inactivation has been shown to play a major role in carcinogenesis, ionizing radiation from cigarette smoke likely plays a role in lung cancer risk. How large a role it plays, relative to chemical carcinogens and other modes of action, remains to be elucidated

  20. Ultraviolet-irradiated simian virus 40 activates a mutator function in rat cells under conditions preventing viral DNA replication

    Energy Technology Data Exchange (ETDEWEB)

    Cornelis, J.; Su, Z.Z.; Dinsart, C.; Rommelaere, J. (Universite libre de Bruxelles, Rhode St Genese (Belgium))

    The UV-irradiated temperature-sensitive early SV40 mutant tsA209 is able to activate at the nonpermissive temperature the expression of mutator and recovery functions in rat cells. Unirradiated SV40 activates these functions only to a low extent. The expression of these mutator and recovery functions in SV40-infected cells was detected using the single-stranded DNA parvovirus H-1 as a probe. Because early SV40 mutants are defective in the initiation of viral DNA synthesis at the nonpermissive temperature, these results suggest that replication of UV-damaged DNA is not a prerequisite for the activation of mutator and recovery functions in mammalian cells. The expression of the mutator function is dose-dependent, i.e., the absolute number of UV-irradiated SV40 virions introduced per cell determines its level. Implications for the interpretation of mutation induction curves in the progeny of UV-irradiated SV40 in permissive host cells are discussed.

  1. Status of radiation dose and radioactive contamination due to the Fukushima accident

    International Nuclear Information System (INIS)

    Baba, Mamoru

    2016-01-01

    The accident at Fukushima Daiichi Nuclear Power Plant (NPP), March 2011, caused serious radioactive contamination over wide area in east Japan. Therefore, it is important to know the effect of the accident and the status of NPP. This paper provides a review on the status of radiation dose and radioactive contamination caused by the accident on the basis of publicized information. Monitoring of radiation dose and exposure dose of residents has been conducted extensively by the governments and various organizations. The effective dose of general residents due to the accident proved to be less than a mSv both for external and internal dose. The equivalent committed dose of thyroid was evaluated to be a few mSv in mean value and less than 50 mSv even for children. Monitoring of radioactivity concentration has been carried out on food ingredients, milk and tap water, and actual meal. These studies indicated the percentage of foods above the regulation standard was over 10% in 2011 but decreasing steadily with time. The internal dose due to foods proved to be tens of μSv and much less than that due to natural 40 K even in the Fukushima area and decreasing steadily, although high level concentration is still observed in wild plants, wild mushrooms, animals and some kind of fishes. According to extensive studies, not only the effect of the accident but also the pathway and countermeasures against radioactive contamination have been revealed, and they are applied very effectively for restoration of environment and reconstruction of the area

  2. Status of radiation dose and radioactive contamination due to the Fukushima accident

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Mamoru [Tohoku Univeristy, Sendai (Japan)

    2016-06-15

    The accident at Fukushima Daiichi Nuclear Power Plant (NPP), March 2011, caused serious radioactive contamination over wide area in east Japan. Therefore, it is important to know the effect of the accident and the status of NPP. This paper provides a review on the status of radiation dose and radioactive contamination caused by the accident on the basis of publicized information. Monitoring of radiation dose and exposure dose of residents has been conducted extensively by the governments and various organizations. The effective dose of general residents due to the accident proved to be less than a mSv both for external and internal dose. The equivalent committed dose of thyroid was evaluated to be a few mSv in mean value and less than 50 mSv even for children. Monitoring of radioactivity concentration has been carried out on food ingredients, milk and tap water, and actual meal. These studies indicated the percentage of foods above the regulation standard was over 10% in 2011 but decreasing steadily with time. The internal dose due to foods proved to be tens of μSv and much less than that due to natural {sup 40}K even in the Fukushima area and decreasing steadily, although high level concentration is still observed in wild plants, wild mushrooms, animals and some kind of fishes. According to extensive studies, not only the effect of the accident but also the pathway and countermeasures against radioactive contamination have been revealed, and they are applied very effectively for restoration of environment and reconstruction of the area.

  3. Occupational radiation doses among diagnostic radiation workers in South Korea, 1996-2006

    International Nuclear Information System (INIS)

    Lee, W. J.; Cha, E. S.; Ha, M.; Jin, Y. W.; Hwang, S. S.; Kong, K. A.; Lee, S. W.; Lee, H. K.; Lee, K. Y.; Kim, H. J.

    2009-01-01

    This study details the distribution and trends of doses of occupational radiation among diagnostic radiation workers by using the national dose registry between 1996 and 2006 by the Korea Food and Drug Administration. Dose measurements were collected quarterly by the use of thermoluminescent dosemeter personal monitors. A total of 61 732 workers were monitored, including 18 376 radiologic technologists (30%), 13 762 physicians (22%), 9858 dentists (16%) and 6114 dental hygienists (9.9%). The average annual effective doses of all monitored workers decreased from 1.75 to 0.80 mSv over the study period. Among all diagnostic radiation workers, radiologic technologists received both the highest effective and collective doses. Male radiologic technologists aged 30-49 y composed the majority of workers receiving more than 5 mSv in a quarter. More intensive monitoring of occupational radiation exposure and investigation into its health effects on diagnostic radiation workers are required in South Korea. (authors)

  4. Factors affecting the In Vitro inactivation of adolase by x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Quintiliani, M.; Boccacci, M.

    1962-08-15

    The influence of urea and of various protective compounds on the in vitro inactivation of aldolase by x rays was studied. Low concentrations of urea protect the enzyme from the inactivation, whereas high concentrations, able to induce an unfolding of the protein molecule, increase the degree inactivation by a given dose of radiation. Cysteamine, cystamine, aminoethyl-isothio-uronium, and glutathione, all protect the aldolase in solution from the inactivation by x rays. Cystamine is as protective as cysteamine, in equimolecular concentrations, when high inactivation levels are reached. No protection can be demonstrated when the aldolase, after incubation with the tested compounds, is precipitated and redissolved in a new medium before irradiation. Nevertheless, with S/sup 35/ labeled cystamine, it can be demonstrated that at least seven residues of cysteamine are bound to each aldolase molecule. The protective power of glutathione is reduced by a factor of about 0.2 in the presence of 4 M urea. The possible implications of these findings are discussed. (auth)

  5. Thermal and high pressure inactivation kinetics of blueberry peroxidase.

    Science.gov (United States)

    Terefe, Netsanet Shiferaw; Delon, Antoine; Versteeg, Cornelis

    2017-10-01

    This study for the first time investigated the stability and inactivation kinetics of blueberry peroxidase in model systems (McIlvaine buffer, pH=3.6, the typical pH of blueberry juice) during thermal (40-80°C) and combined high pressure-thermal processing (0.1-690MPa, 30-90°C). At 70-80°C, the thermal inactivation kinetics was best described by a biphasic model with ∼61% labile and ∼39% stable fractions at temperature between 70 and 75°C. High pressure inhibited the inactivation of the enzyme with no inactivation at pressures as high as 690MPa and temperatures less than 50°C. The inactivation kinetics of the enzyme at 60-70°C, and pressures higher than 500MPa was best described by a first order biphasic model with ∼25% labile fraction and 75% stable fraction. The activation energy values at atmospheric pressure were 548.6kJ/mol and 324.5kJ/mol respectively for the stable and the labile fractions. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  6. Radiation exposure of the radiologist's eye lens during CT-guided interventions.

    Science.gov (United States)

    Heusch, Philipp; Kröpil, Patric; Buchbender, Christian; Aissa, Joel; Lanzman, Rotem S; Heusner, Till A; Ewen, Klaus; Antoch, Gerald; Fürst, Günther

    2014-02-01

    In the past decade the number of computed tomography (CT)-guided procedures performed by interventional radiologists have increased, leading to a significantly higher radiation exposure of the interventionalist's eye lens. Because of growing concern that there is a stochastic effect for the development of lens opacification, eye lens dose reduction for operators and patients should be of maximal interest. To determine the interventionalist's equivalent eye lens dose during CT-guided interventions and to relate the results to the maximum of the recommended equivalent dose limit. During 89 CT-guided interventions (e.g. biopsies, drainage procedures, etc.) measurements of eye lens' radiation doses were obtained from a dedicated dosimeter system for scattered radiation. The sensor of the personal dosimeter system was clipped onto the side of the lead glasses which was located nearest to the CT gantry. After the procedure, radiation dose (µSv), dose rate (µSv/min) and the total exposure time (s) were recorded. For all 89 interventions, the median total exposure lens dose was 3.3 µSv (range, 0.03-218.9 µSv) for a median exposure time of 26.2 s (range, 1.1-94.0 s). The median dose rate was 13.9 µSv/min (range, 1.1-335.5 µSv/min). Estimating 50-200 CT-guided interventions per year performed by one interventionalist, the median dose of the eye lens of the interventional radiologist does not exceed the maximum of the ICRP-recommended equivalent eye lens dose limit of 20 mSv per year.

  7. Radiation Dose Measurements with Direction and from Patients Undergoing Nuclear Medicine Investigations

    International Nuclear Information System (INIS)

    AL-Shakhrah, I.

    2003-01-01

    Rdiologists and technologists are occasionally concerned about the radiation exposure that they may receive during the performance of routine diagnostic radiologic studies, that require close proximity to a patient who has recently had a radionuclide imaging procedure. This also impacts on other medical personnel including porters, nurses, pathologists, etc. This study was conducted in order to calculate the radiation exposure that one may anticipate receiving from a patient who has recently had a nuclear midicine procedure. Radiation dose rate (μSv/hr) was measured in 34 patients for four commonly performed nuclear medicine procedures (bone, liver/spleen, renal and thyroid) at the skin surface, 10,30,60,100, and at 150 cm from the patient, within 3 and 1hr ( 3 hrs for bone scan patients and 1 hr for the other three procedures ) postinjection, with a digital survey meter. The measurements were performed also for different sides of the patients ( anterior, posterior, left and right). For bone scans, a dose of 714.1 ± 96.2 MBq ( 19.3 ± 2.6mCi ) of technetium-99m-MDP ( 99 m Tc-MDP) resulted in a radiation exposure ( from posterior side of the patient )of ( 195±41) μSv/hr at the skin surface, (110±27) μSv/hr at 10cm, (51±10) μSv/hr at 30cm, (21±5) μSv/hr at 60cm, (10±2) μSv/hr at 1m, and (6±2) μSv/hr at 1.5m. Also for the bone, the radiation dose rate measurements obtained (from left side of the patient ) were 144±30) μSv/hr at the skin surface, ( 90±21) μSv/hr at 10cm, ( 36±8)μSv/hr at30cm, (15±3)μSv/hr at 60cm, (8±2)μSv/hr at 1 m,and ( 4±1)μSv/hr at 1.5m. It has been found that the variations in percentage (%) between posterior and left side mean measurments were 28.2, 18.2, 29.4, 25.0, 20.0 and 33.3 at the skin, 10cm,30cm,60cm, 100cm and 150 cm respectively. When we search for ''conservative'' values and concepts, concerning the radiation safety in nuclear medicine department , we believe that anterior and posterior sides values must be

  8. Identification of risk aversion factor for radiation workers in Korea

    International Nuclear Information System (INIS)

    Fadul, Abdulbagi; Na, Seong H.

    2016-01-01

    Radiation aversion factor reflects the degree of avoidance of radiation exposure which is considered a fundamental element in the optimization of radiation protection and a key factor in determining the real monetary value of the man-Sievert (Sv). This study provides an adjusted risk aversion factor, which was prescribed by the Korea Institute for Nuclear Safety (KINS), a regulatory body in Korea. Specifically, the Korea Hydro and Nuclear Power Co., Ltd. (KHNP) evaluated the monetary value of the man-Sv for Korean Nuclear Power Plants (NPPs) workers. This monetary value was assessed by the radiation aversion factor. Consequently, identifying the monetary value of the man-Sv in this study will enhance not only the effectiveness of optimization of radiation protection in Korea but also contribute to reduce doses to As Low As Reasonably Achievable (ALARA) when accounting for economic and societal aspects. The primary purpose of this study is to obtain the risk aversion factor for radiation workers in medical and industrial facilities in Korea. The secondary purpose is to evaluate the real monetary value of the man-Sv.These objectives will be accomplished by collecting data from surveys that consider a variety of socio-economic conditions. The value of 1.45 represents considerable avoidance of radiation risk for the majority of NDT radiographers due to familiarity and work experience with radiation hazards. On the other hand, the value 1.57 indicates that most of radiation medical practitioners, in particular, interventional radiologists have a strong will to avoid radiation risk. However, they will accept more risk with incremental salary increases. For international comparison, the concept of Purchasing Power Parity (PPP) should be adopted to obtain the alpha values in real term. Certainly, this monetary value of the man-Sv is expected to contribute effectively in optimization of radiation protection in both medical and industrial fields. The findings of this study

  9. Identification of risk aversion factor for radiation workers in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Fadul, Abdulbagi [KAIST, Daejeon (Korea, Republic of); Na, Seong H. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-10-15

    Radiation aversion factor reflects the degree of avoidance of radiation exposure which is considered a fundamental element in the optimization of radiation protection and a key factor in determining the real monetary value of the man-Sievert (Sv). This study provides an adjusted risk aversion factor, which was prescribed by the Korea Institute for Nuclear Safety (KINS), a regulatory body in Korea. Specifically, the Korea Hydro and Nuclear Power Co., Ltd. (KHNP) evaluated the monetary value of the man-Sv for Korean Nuclear Power Plants (NPPs) workers. This monetary value was assessed by the radiation aversion factor. Consequently, identifying the monetary value of the man-Sv in this study will enhance not only the effectiveness of optimization of radiation protection in Korea but also contribute to reduce doses to As Low As Reasonably Achievable (ALARA) when accounting for economic and societal aspects. The primary purpose of this study is to obtain the risk aversion factor for radiation workers in medical and industrial facilities in Korea. The secondary purpose is to evaluate the real monetary value of the man-Sv.These objectives will be accomplished by collecting data from surveys that consider a variety of socio-economic conditions. The value of 1.45 represents considerable avoidance of radiation risk for the majority of NDT radiographers due to familiarity and work experience with radiation hazards. On the other hand, the value 1.57 indicates that most of radiation medical practitioners, in particular, interventional radiologists have a strong will to avoid radiation risk. However, they will accept more risk with incremental salary increases. For international comparison, the concept of Purchasing Power Parity (PPP) should be adopted to obtain the alpha values in real term. Certainly, this monetary value of the man-Sv is expected to contribute effectively in optimization of radiation protection in both medical and industrial fields. The findings of this study

  10. Inactivation of Coxiella burnetti by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, G.H.; McCaul, T.F.; Williams, J.C.

    1989-01-01

    The gamma radiation inactivation kinetics for Coxiella burnetii at - 79 C were exponential. The radiation dose needed to reduce the number of infective C. burnetii by 90% varied from 0-64 to 1.2 kGy depending on the phase of hte micro-organism, purity of the culture and composition of suspending menstruum. The viability of preparations containing C. burnetti was completely abolished by 10 kGy without diminishing antigenicity or ability to elicit a protective immune response in vaccinated mice. Immunocytochemical examinations using monoclonal antibodies and electron microscopy demonstrated that radiation doses of 20 kGy did not alter cell-wall morphology or cell-surface antigenic epitopes.

  11. Cell extracts of propionic acid bacteria reactivate cells of Escherichia coli inactivated by ultraviolet radiation

    International Nuclear Information System (INIS)

    Vorob'eva, L.I.; Nikitenko, G.V.; Khodzhaev, E.Yu.; Ponomareva, G.M.

    1994-01-01

    Cell extracts of three Propionibacterium shermanii strains were shown to exert a reactivating effect on cells of E. coli AB 1157 inactivated by ultraviolet radiation. The reactivating effect was revealed after both preincubation and postincubation of the irradiated cells with the extracts. The effect increased with a decrease of the survival rate within the range of 1.8-0.006%. The protective factor (or factors) is dialyzable and thermolabile; it was detected both in the fraction of soluble proteins and in the fraction of nucleoproteins and nucleic acids. The protective properties of dialyzate disappear after incubation with proteinase K and trypsin, decrease after incubation with α-amylase, deoxyribonuclease-1, or ribonuclease, and do not change under the influence of lipase. The reactivating factor is believed to be of a polypeptide nature

  12. Natural radionuclides in the human body; Natuerliche Radionuklide im menschlichen Koerper

    Energy Technology Data Exchange (ETDEWEB)

    Voelkle, Hansruedi [Fribourg Univ. (Switzerland). Physikdept.

    2017-08-01

    Natural radionuclides in the human body produce worldwide a medium annual radiation exposure of 0.31 mSv. 0.17 mSv are due to potassium-40 (K-40) per year, 0.12 mSv per year are due to radionuclides from the uranium and thorium decay series, less than 0.02 mSv due to cosmogenic radionuclides. Natural radioactivity is therefore the largest exposure source, anthropogenic exposure is comparatively marginal.

  13. Simian virus 40 inhibits differentiation and maturation of rhesus macaque DC-SIGN+-dendritic cells

    Directory of Open Access Journals (Sweden)

    Changyong G

    2010-09-01

    Full Text Available Abstract Dendritic cells (DC are the initiators and modulators of the immune responses. Some species of pathogenic microorganisms have developed immune evasion strategies by controlling antigen presentation function of DC. Simian virus 40 (SV40 is a DNA tumor virus of rhesus monkey origin. It can induce cell transformation and tumorigenesis in many vertebrate species, but often causes no visible effects and persists as a latent infection in rhesus monkeys under natural conditions. To investigate the interaction between SV40 and rhesus monkey DC, rhesus monkey peripheral blood monocyte-derived DC were induced using recombinant human Interleukin-4 (rhIL-4 and infective SV40, the phenotype and function of DC-specific intracellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN+ DC were analyzed by flow cytometry (FCM and mixed lymphocyte reaction (MLR. Results showed that SV40 can down-regulate the expression of CD83 and CD86 on DC and impair DC-induced activation of T cell proliferation. These findings suggest that SV40 might also cause immune suppression by influencing differentiation and maturation of DC.

  14. Staff radiation exposure in radiation diagnostics

    International Nuclear Information System (INIS)

    Khakimova, N.U.; Malisheva, E.Yu.; Shosafarova, Sh.G.

    2010-01-01

    Present article is devoted to staff radiation exposure in radiation diagnostics. Data on staff radiation exposure obtained during 2005-2008 years was analyzed. It was found that average individual doses of staff of various occupations in Dushanbe city for 2008 year are at 0.29-2.16 mSv range. They are higher than the average health indicators but lower than maximum permissible dose. It was defined that paramedical personnel receives the highest doses among the various categories of staff.

  15. Radiation problems of Fukushima. Little exposure of residents

    International Nuclear Information System (INIS)

    Togasawa, Hidetoshi

    2012-01-01

    More than one and half year passed after Fukushima nuclear accident, radiation hazards, especially due to internal irradiation, were still public concern of people living within Fukushima prefecture and Tokyo metropolitan area. However according to several investigations, internal exposure was greatly lower than the level of health hazards due to internal radiation. In August 2012, Fukushima prefecture published internal dose rate of 26 persons was greater than 1 mSv (max 3 mSv) and others than 1 mSv based on whole body counters test results for 63366 residents after June 2011. Appropriate disclosure of exposure dose and related risks was required for risk communication. Target of internal exposure dose rate less than 1 mSv/year was almost attained and people with rather higher dose should be individually checked to reduce exposure. (T. Tanaka)

  16. Radiological impact of natural and artificial sources of ionizing radiation. Report UNSCEAR 2000

    International Nuclear Information System (INIS)

    Cancio, D.

    2001-01-01

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was established by the General Assembly in 1995. It has the mandate to assess the levels and effects of ionizing radiation. During the last years UNSCEAR has undertaken a broad review of the natural and artificial sources of ionizing radiation. The results of these evaluations have been presented in a Report to the General Assembly with Scientific Annexes including extensive data for the world community (Report UNSCEAR 2000). The greatest contribution to radiation exposure comes from natural background sources. There are considerable variation in the exposures of the population depending on the altitude and latitude, characteristics of the soil and diet and the construction and ventilation features of houses. The global annual average per caput is 2.4 mSv with typical range 1 to 10 mSv. The next largest component comes from medical radiation examinations and treatments with an annual average of 0.4 mSv ranging from 0.04 to 1.0 mSv depending on the level o f medical care. The man-made practices, activities, and events in which radionuclides are released to the environment are always of much concern, but usually they contribute quite low to radiation exposure to humans. Atmospheric testing caused the greatest releases but nowadays very low residual annual levels of exposures persist (0.005 mSv). Nuclear Power production is responsible for only very low exposure and may reach in the future an average annual level of 0.0002 mSv. (Author)

  17. Uranium, radium and 40K isotopes in bottled mineral waters from Outer Carpathians, Poland

    International Nuclear Information System (INIS)

    Kozlowska, B.; Walencik, A.; Dorda, J.; Przylibski, T.A.

    2007-01-01

    Radioactivity content in commercially bottled mineral waters from Outer Carpathians was investigated on the basis of 28 samples. Activity concentration results for radium isotopes 226,228 Ra, uranium isotopes 234,238 U and isotopic ratios 234 U/ 238 U were determined. The correlations between investigated isotopes and calculated potassium 40 K ions dissolved in water were carried out. The results show a correlation between TDS (total dissolved solids) values and dissolved radionuclides. High correlation coefficients were observed between total radium content and 40 K. The isotopic ratio of 234 U/ 238 U varies in the range from 1.6 to 7 in all investigated waters which means that there is no radioactive equilibrium between the parent nuclide 238 U and its daughter 234 U. The effective radiation dose coming from studied radium and uranium radionuclides consumed with mineral water from the Outer Carpathians obtained by a statistical Pole is equal to 4.3μSv/year (58 l/year water consumption) and do not exceed the permissible limit equal to 100μSv/year. Assuming 0.5 l consumption per day, i.e. 182.5 l/year, the effective dose is equal to 13.4μSv/year, what is still below the unit

  18. Evaluation of radiation dose to patients in intraoral dental radiography using Monte Carlo Method

    International Nuclear Information System (INIS)

    Park, Il; Kim, Kyeong Ho; Oh, Seung Chul; Song, Ji Young

    2016-01-01

    The use of dental radiographic examinations is common although radiation dose resulting from the dental radiography is relatively small. Therefore, it is required to evaluate radiation dose from the dental radiography for radiation safety purpose. The objectives of the present study were to develop dosimetry method for intraoral dental radiography using a Monte Carlo method based radiation transport code and to calculate organ doses and effective doses of patients from different types of intraoral radiographies. Radiological properties of dental radiography equipment were characterized for the evaluation of patient radiation dose. The properties including x-ray energy spectrum were simulated using MCNP code. Organ doses and effective doses to patients were calculated by MCNP simulation with computational adult phantoms. At the typical equipment settings (60 kVp, 7 mA, and 0.12 sec), the entrance air kerma was 1.79 mGy and the measured half value layer was 1.82 mm. The half value layer calculated by MCNP simulation was well agreed with the measurement values. Effective doses from intraoral radiographies ranged from 1 μSv for maxilla premolar to 3 μSv for maxilla incisor. Oral cavity layer (23⁓82 μSv) and salivary glands (10⁓68 μSv) received relatively high radiation dose. Thyroid also received high radiation dose (3⁓47 μSv) for examinations. The developed dosimetry method and evaluated radiation doses in this study can be utilized for policy making, patient dose management, and development of low-dose equipment. In addition, this study can ultimately contribute to decrease radiation dose to patients for radiation safety

  19. Evaluation of radiation dose to patients in intraoral dental radiography using Monte Carlo Method

    Energy Technology Data Exchange (ETDEWEB)

    Park, Il; Kim, Kyeong Ho; Oh, Seung Chul; Song, Ji Young [Dept. of Nuclear Engineering, Kyung Hee University, Yongin (Korea, Republic of)

    2016-11-15

    The use of dental radiographic examinations is common although radiation dose resulting from the dental radiography is relatively small. Therefore, it is required to evaluate radiation dose from the dental radiography for radiation safety purpose. The objectives of the present study were to develop dosimetry method for intraoral dental radiography using a Monte Carlo method based radiation transport code and to calculate organ doses and effective doses of patients from different types of intraoral radiographies. Radiological properties of dental radiography equipment were characterized for the evaluation of patient radiation dose. The properties including x-ray energy spectrum were simulated using MCNP code. Organ doses and effective doses to patients were calculated by MCNP simulation with computational adult phantoms. At the typical equipment settings (60 kVp, 7 mA, and 0.12 sec), the entrance air kerma was 1.79 mGy and the measured half value layer was 1.82 mm. The half value layer calculated by MCNP simulation was well agreed with the measurement values. Effective doses from intraoral radiographies ranged from 1 μSv for maxilla premolar to 3 μSv for maxilla incisor. Oral cavity layer (23⁓82 μSv) and salivary glands (10⁓68 μSv) received relatively high radiation dose. Thyroid also received high radiation dose (3⁓47 μSv) for examinations. The developed dosimetry method and evaluated radiation doses in this study can be utilized for policy making, patient dose management, and development of low-dose equipment. In addition, this study can ultimately contribute to decrease radiation dose to patients for radiation safety.

  20. Inactivation of Caliciviruses

    Directory of Open Access Journals (Sweden)

    Raymond Nims

    2013-03-01

    Full Text Available The Caliciviridae family of viruses contains clinically important human and animal pathogens, as well as vesivirus 2117, a known contaminant of biopharmaceutical manufacturing processes employing Chinese hamster cells. An extensive literature exists for inactivation of various animal caliciviruses, especially feline calicivirus and murine norovirus. The caliciviruses are susceptible to wet heat inactivation at temperatures in excess of 60 °C with contact times of 30 min or greater, to UV-C inactivation at fluence ≥30 mJ/cm2, to high pressure processing >200 MPa for >5 min at 4 °C, and to certain photodynamic inactivation approaches. The enteric caliciviruses (e.g.; noroviruses display resistance to inactivation by low pH, while the non-enteric species (e.g.; feline calicivirus are much more susceptible. The caliciviruses are inactivated by a variety of chemicals, including alcohols, oxidizing agents, aldehydes, and β-propiolactone. As with inactivation of viruses in general, inactivation of caliciviruses by the various approaches may be matrix-, temperature-, and/or contact time-dependent. The susceptibilities of the caliciviruses to the various physical and chemical inactivation approaches are generally similar to those displayed by other small, non-enveloped viruses, with the exception that the parvoviruses and circoviruses may require higher temperatures for inactivation, while these families appear to be more susceptible to UV-C inactivation than are the caliciviruses.

  1. Ionizing radiation as a source of both occupational and public exposure. Is there any difference between them? Conclusions for radiation protection practice

    International Nuclear Information System (INIS)

    Vassilev, G.

    2000-01-01

    The assessment of the radiation risk both from natural and occupational exposure is discussed, taking into account the values for the end of 20th century for Bulgaria. The natural background exposure in the country is in average of 2.3 mSv/a. The eternal exposure in different regions varies within the range of ±25%. The radon concentration in dwellings vary in wide range: from 2.5 to 250 Bq/m 3 at a geometrical mean of 22 Bq/m 3 (equilibrium equivalent concentration). Thus the natural exposure vary from 1.0 to 5 mSv/a. The occupational exposure in different fields is as follows: medicine - 1.0 mSv/a; science, education - 0.9 mSv/a; NPP workers - 2.0 mSv/a. Taking into account that this way the risk equalizes for each population group the following conclusions are made: necessity for rendering an account of the individual natural background exposure when occupational risk is assessed; building of an adequate national system for record and limitation of exposure my medical use of ionizing radiation; improvement of the system for limitation of the radon exposure; re-examination of dosimetry control for occupational exposure; reconsidering of the social compensation for radiation risk

  2. Specifications for Testing Procedures at Svåheia

    DEFF Research Database (Denmark)

    Margheritini, Lucia; Kofoed, Jens Peter

    This report is realized in order to define testing procedures of the SSG pilot in Svåheia location. This will be done by listing all the relevant parameters related to the structure performance.......This report is realized in order to define testing procedures of the SSG pilot in Svåheia location. This will be done by listing all the relevant parameters related to the structure performance....

  3. Cosmic radiation and air crew exposure

    International Nuclear Information System (INIS)

    Vukovic, B.; Lisjak, I.; Vekic, B.; Planinic, J.

    2005-01-01

    When the primary particles from space, mainly protons, enter the atmosphere, they interact with the air nuclei and induce cosmic-ray shower. When an aircraft is in the air, the radiation field within includes many types of radiation of large energy range; the field comprises mainly photons, electrons, positrons and neutrons. Cosmic radiation dose for crews of air crafts A 320 and ATR 42 was measured using TLD-100 (LiF: Mg, Ti) detectors and the Mini 6100 semiconductor dosimeter; radon concentration in the atmosphere was measured using the Alpha Guard radon detector. The total annual dose estimated for the A 320 aircraft crew, at altitudes up to 12000 meters, was 5.3 mSv (including natural radon radiation dose of 1.1 mSv).(author)

  4. Inactivation of bacterial spores by combination processes: ultraviolet plus gamma radiation. [Streptococcus faecium, micrococcus radiodurans, clostridium botulinum

    Energy Technology Data Exchange (ETDEWEB)

    Grecz, N; Durban, E

    1973-01-01

    Bacterial spores, viruses and some vegetative bacteria such as Streptococcus faecium and Micrococcus radiodurans are distinguished by high radiation resistance. In order to lay a theoretical basis for biomedical sterilization applications, we have investigated the combined action of uv and gamma rays. Spores of two strains of C. botulinum were selected, a highly radiation resistant strain, 33A having a D/sub 10/-value of 0.32 Mrad, and a relatively radiation sensitive strain, 51B having a D/sub 10/-value of 0.12 Mrad. Strain 33A exhibits an extensive initial ''shoulder'' in its uv as well as gamma ray survival curves; strain 51B shows only a slight shoulder. The shoulder in the gamma ray survival curve of spores of strain 33A could be reduced or completely eliminated by preirradiation with uv. Simultaneously the D/sub 10/-value for gamma inactivation of spores of 33A was reduced substantially. For example, the gamma resistance was reduced almost to half of its original D/sub 10/-value by uv-preirradiation for only one minute under an 8 watt GE germicidal lamp. The effect of uv-preirradiation on the radiation sensitive strain 51B was less pronounced. In fact, there was about seven fold higher positive interaction (synergism) between uv and gamma radiation in 33A spores than in 51B spores. The experiments suggest that interference with DNA repair enzymes in the radiation resistant strain are responsible for lethal synergism between uv and gamma radiation. A hypothesis is developed attempting to explain the combined effect of these two radiations in terms of a special summation of known DNA lesions in the cell. These observations emphasize the potential practical advantages of combining uv and gamma rays for effective sterilization of certain biomedical devices, drugs and biologicals.

  5. Natural background radiation in Canada

    International Nuclear Information System (INIS)

    Grasty, R.L.; Carson, J.M.; Charbonneau, B.W.; Holman, P.B.

    1984-01-01

    Published airborne gamma ray survey data from 33 areas of Canada were used to compile information on the average ground level exposure from natural radiation. The exposures at ground level were calculated from the surface concentrations of potassium, uranium and thorium. The highest levels of radioactivity were found in northern Canada and were generally related to granitic rocks; the lowest levels with the Athabasca sandstone. Summer outdoor exposure rates have a population-weighted average of 3.7 +- 2.3 μR.h -1 , of which 48 percent orginated from potassium, 43 percent from the thorium series and 9 percent from the uranium series. This low level of radioactivity, compared to worldwide data, has resulted from erosion of a geologically old continental crust in which radioactivity decreases with depth. When seasonal variations of soil moisture and snow cover are considered, the annual population-weighted average outdoor exposure rate decreases to 2.8 +- 1.7 μR.h -1 corresponding to an annual outdoor dose-equivalent of 150 +- 90 μSV. Factors increasing the annual outdoor dose-equivalent are cosmic radiation (320 +- 30 μSV) and the internal radioactivity of the body (190 μSV). Using the ratio between indoor and outdoor values for worldwide published data, the average annual Canadian whole-body dose-equivalent from all sources of natural radiation is estimated to be 690 +-130 μSV

  6. Method of inactivation of viral and bacterial blood contaminants

    International Nuclear Information System (INIS)

    Hackett, R.; Goodrich, R.P.; Van Borssum Waalkes, M.; Wong, V.A.

    1992-01-01

    A method is provided for inactivating viral and/or bacterial contamination in blood cellular matter, such as erythrocytes and platelets, or protein fractions. The cells or protein fractions are mixed with chemical sensitizers and irradiated with, for example, gamma or X-ray radiation

  7. Estimated cumulative radiation dose received by diagnostic imaging during staging and treatment of operable Ewing sarcoma 2005-2012

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, Boel [Haukeland University Hospital, Centre for Nuclear Medicine and PET, Department of Radiology, P.O. Box 1400, Bergen (Norway); Fasmer, Kristine Eldevik [Haukeland University Hospital, Department of Oncology, Medical Physics Section, Bergen (Norway); Boye, Kjetil [Norwegian Radium Hospital, Oslo University Hospital, Department of Oncology, Oslo (Norway); Rosendahl, Karen; Aukland, Stein Magnus [Haukeland University Hospital, Department of Radiology, Paediatric Section, Bergen (Norway); University of Bergen, Department of Clinical Medicine, Bergen (Norway); Trovik, Clement [University of Bergen, Department of Clinical Medicine, Bergen (Norway); Haukeland University Hospital, Department of Surgery, Orthopaedic Section, Bergen (Norway); Biermann, Martin [Haukeland University Hospital, Centre for Nuclear Medicine and PET, Department of Radiology, P.O. Box 1400, Bergen (Norway); University of Bergen, Department of Clinical Medicine, Bergen (Norway)

    2017-01-15

    Patients with Ewing sarcoma are subject to various diagnostic procedures that incur exposure to ionising radiation. To estimate the radiation doses received from all radiologic and nuclear imaging episodes during diagnosis and treatment, and to determine whether {sup 18}F-fluorodeoxyglucose positron emission tomography - computed tomography ({sup 18}F-FDG PET-CT) is a major contributor of radiation. Twenty Ewing sarcoma patients diagnosed in Norway in 2005-2012 met the inclusion criteria (age <30 years, operable disease, uncomplicated chemotherapy and surgery, no metastasis or residual disease within a year of diagnosis). Radiation doses from all imaging during the first year were calculated for each patient. The mean estimated cumulative radiation dose for all patients was 34 mSv (range: 6-70), radiography accounting for 3 mSv (range: 0.2-12), CT for 13 mSv (range: 2-28) and nuclear medicine for 18 mSv (range: 2-47). For the patients examined with PET-CT, the mean estimated cumulative effective dose was 38 mSv, of which PET-CT accounted for 14 mSv (37%). There was large variation in number and type of examinations performed and also in estimated cumulative radiation dose. The mean radiation dose for patients examined with PET-CT was 23% higher than for patients not examined with PET-CT. (orig.)

  8. Ionizing radiation dose due to the use of agricultural fertilizers

    International Nuclear Information System (INIS)

    Umisedo, Nancy Kuniko

    2007-01-01

    Among several agents that exist in the environment which can expose to different risks and effects, there is the ionizing radiation whose knowledge of dose is of importance to the effective control and prevention of possible damages to human beings and to the environment. The transfer of radionuclides from fertilizers to/and soils to the foodstuffs can result as an increment in the internal dose when they are consumed by the human beings. This work evaluates the contribution of fertilizers to the ionizing radiation dose in the environment and in the human being. Samples of fertilizers, soils and vegetables produced in fertilized soils were analysed through gamma spectrometry with the use of a hyper pure germanium detector. Measurements of ambient dose with thermoluminescent dosimeters were also performed. In the fertilized soil samples values of specific activities from 36 to 342 Bq/kg for K-40, from 42 to 142 Bq/kg for U-238 and from 36 to 107 Bq/kg for Th-232 were obtained. In the vegetables the values varied from 21 to 118 Bq/kg for K-40 and for the elements of uranium and thorium series the values were less than 2 Bq/kg. In fertilizers the maximum value of 5800 Bq/kg was obtained for K-40, 430 Bq/kg for U-238 and 230 Bq/kg for Th-232. The average values of soil to plant transfer factor were not significantly different among the types of vegetables. The annual committed effective dose of 0.882 μSv due to the ingestion of K-40 from the analysed vegetables is very small if compared to the reference value of 170 μv given by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000). The thermoluminescent dosimetry provided the annual ambient dose equivalent from 1.5 to 1.8 mSv without differences between cultivated and non cultivated fields. Through the results obtained, it was not observed a significant transfer of radionuclides from fertilizers to soils and to foodstuffs in the conditions adopted in this work and consequently there

  9. Radiation enhanced reactivation of nuclear replicating mammalian viruses

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Lytle, C.D.

    1977-01-01

    When CV-1 monkey kidney cells were UV-irradiated (0 to 18 J/m 2 ) or X-irradiated (0 to 10 krads) before infection with UV-irradiated simian adenovirus 7 (SA7) or simian virus 40 (SV40), increases in the infectivity of these nuclear replicating viruses as measured by plaque formation were observed. These radiation enhanced reactivations, UV enhanced reactivation (UVER) and X-ray enhanced reactivation (X-ray ER), occurred both when virus infection immediately followed irradiation of the cells (except for X-ray ER with SA7) and when virus infection was delayed until 3 to 5 days after cell irradiation. While there was little difference in the levels of reactivation of UV-irradiated SV40 between immediate and delayed infection, delayed infection resulted in higher levels of reactivation of SA7. X-ray enhanced reactivation of UV-irradiated Herpes simplex virus persisted for several days but did not increase. Thus, X-ray enhanced and UV enhanced reactivations of these mammalian viruses were relatively long-lived effects. Essentially no UVER or X-ray ER was found in CV-1 cells for either immediate or delayed infection with UV-irradiated vaccinia virus or poliovirus, both of which replicate in the cell cytoplasm. These results suggest UVER and X-ray ER in mammalian cells may be restricted to viruses which are replicated in the cell nucleus. (author)

  10. Workers radiation protection. Occupational exposure to ionizing radiations in France: 2015 results. 2016 Mission report

    International Nuclear Information System (INIS)

    2016-06-01

    National results of the individual monitoring of occupational exposure to ionizing radiation are reported for all civilian and military activities subject to authorization or declaration (i.e. medical and veterinary activities, nuclear industry, defence, non-nuclear industry and research), as well as for activities concerned by the enhanced exposure to natural radiation. 365 830 workers within activities subject to authorization or declaration were monitored by passive dosimetry in 2015, which represents an increase by 1.7 % compared to 2014. The average individual dose in 2015 was very close to the value in 2014. Furthermore, 14 138 workers received more than 1 mSv (i.e. the legal dose limit for the public), and 2 606 workers received more than 5 mSv. 2 workers received more than 20 mSv (i.e. the dose limit for the workers in the French regulation). As a result, the collective dose increased from 56.3 to 61.9 man.Sv (10 %), thus reaching the same level as in the years 2009 to 2013. Important differences are noticed according to the occupational activities: the average dose in the medical and veterinary field (which represents 62.4 % of the monitored workers) and that in the research field (3.6 % of the monitored workers) are less than 0.4 mSv; the average doses are higher in the nuclear field and in the non-nuclear industry (representing together 30.1 % of the monitored workers), respectively 1.17 mSv and 1.38 mSv. Concerning internal dosimetry, 279 877 individual examinations have been performed in 2015, 52 % of which are radio-toxicological analysis of excreta and 48 % are direct body counting. In 2015, 2 workers had a committed effective dose greater than or equal to 1 mSv and the maximum dose was 3 mSv. Data or trends relative to workers exposed to natural radioactivity are also dealt with in this report (air crews, personnel subjected to radon exposure). In particular, results of aircrew dosimetry are reported: in 2015, the average individual dose of 19 565

  11. Response of bacteria in wastewater sludge to moisture loss by evaporation and effect of moisture content on bacterial inactivation by ionizing radiation.

    OpenAIRE

    Ward, R L; Yeager, J G; Ashley, C S

    1981-01-01

    Two studies were carried out to determine the influence of moisture content of the survival of bacteria in raw wastewater sludge. The first study involved the effect of water loss by evaporation on the bacterial population. The second used these dewatered samples to measure the effects of moisture content on the inactivation of bacteria sludge by ionizing radiation. Both studies involved survival measurements of six representative fecally associated bacteria grown separately in sterilized slu...

  12. Measurement of background gamma radiation in the northern Marshall Islands.

    Science.gov (United States)

    Bordner, Autumn S; Crosswell, Danielle A; Katz, Ainsley O; Shah, Jill T; Zhang, Catherine R; Nikolic-Hughes, Ivana; Hughes, Emlyn W; Ruderman, Malvin A

    2016-06-21

    We report measurements of background gamma radiation levels on six islands in the northern Marshall Islands (Enewetak, Medren, and Runit onEnewetak Atoll; Bikini and Nam on Bikini Atoll; and Rongelap on Rongelap Atoll). Measurable excess radiation could be expected from the decay of (137)Cs produced by the US nuclear testing program there from 1946 to 1958. These recordings are of relevance to safety of human habitation and resettlement. We find low levels of gamma radiation for the settled island of Enewetak [mean = 7.6 millirem/year (mrem/y) = 0.076 millisievert/year (mSv/y)], larger levels of gamma radiation for the island of Rongelap (mean = 19.8 mrem/y = 0.198 mSv/y), and relatively high gamma radiation on the island of Bikini (mean = 184 mrem/y = 1.84 mSv/y). Distributions of gamma radiation levels are provided, and hot spots are discussed. We provide interpolated maps for four islands (Enewetak, Medren, Bikini, and Rongelap), and make comparisons to control measurements performed on the island of Majuro in the southern Marshall Islands, measurements made in Central Park in New York City, and the standard agreed upon by the United States and the Republic of the Marshall Islands (RMI) governments (100 mrem/y = 1 mSv/y). External gamma radiation levels on Bikini Island significantly exceed this standard (P = <0.01), and external gamma radiation levels on the other islands are below the standard. To determine conclusively whether these islands are safe for habitation, radiation exposure through additional pathways such as food ingestion must be considered.

  13. Progressive paralysis associated with diffuse astrocyte anaplasia in delta 202 mice homozygous for a transgene encoding the SV40 T antigen.

    Science.gov (United States)

    López-Revilla, Rubén; Soto-Zárate, Carlos; Ridaura, Cecilia; Chávez-Dueñas, Lucía; Paul, Dieter

    2004-03-01

    A convenient transgenic astrocytoma model in delta202 mice, homozygous for a construct encoding the early region of the SV40 virus genome, is described. In the offspring of crosses between delta202 mice heterozygous for the transgene nearly 60% were transgenic; one third of these developed progressive paralysis starting in the hindlimbs at approximately 35 days of age and died at 90 +/- 30 days of age. In affected mice proliferating-non-neuronal cells immunostained with antibodies to the GFAP, an astrocyte marker, whose number increased with age were found in the white matter of the brain, cerebellum and spinal cord, and progressive degeneration and necrosis of spinal motoneurons was observed that-may explain the paralysis. The early onset and reproducible time course of the neurological disease suggest that homozygous delta202 mice, whose proliferating astrocytes appear to damage spinal motoneurons, are a useful model to study astrocyte differentiation, function and tumorigenesis.

  14. Dose Rate of Environmental Gamma Radiation in Java Island

    International Nuclear Information System (INIS)

    Gatot Suhariyono; Buchori; Dadong Iskandar

    2007-01-01

    The dose rate Monitoring of environmental gamma radiation at some locations in Java Island in the year 2005 / 2006 has been carried out. The dose rate measurement of gamma radiation is carried out by using the peripheral of Portable Gamma of Ray Spectrometer with detector of NaI(Tl), Merck Exploranium, Model GR-130- MINISPEC, while to determine its geographic position is used by the GPS (Global Positioning System), made in German corporation of GPS III Plus type. The division of measurement region was conducted by dividing Java Island become 66 parts with same distance, except in Jepara area that will built PLTN (Nuclear Energy Power), distance between measurement points is more closed. The results of dose rate measurement are in 66 locations in Java Island the range of (19.24 ± 4.05) nSv/hour until (150.78 ± 12.26) nSv/hour with mean (51.93 ± 36.53) nSv/h. The lowest dose rate was in location of Garut, while highest dose rate was in Ujung Lemah Abang, Jepara location. The data can be used for base line data of dose rate of environmental gamma radiation in Indonesia, specially in Java Island. The mean level of gamma radiation in Java monitoring area (0.46 mSv / year) was still lower than worldwide average effective dose rate of terrestrial gamma rays 0.5 mSv / year (report of UNSCEAR, 2000). (author)

  15. Modification of radiation damage in CHO cells by hyperthermia at 40 and 450C

    International Nuclear Information System (INIS)

    Henle, K.J.; Leeper, D.B.

    1977-01-01

    Low hyperthermia at 40 0 C either before or after X irradiation did not alter the slope of the radiation dose-cell survival curve but reduced the D/sub q/ from 145 to 41 or to 0 rad for a pre- or postirradiation incubation period of 2 hr at 40 0 C, respectively. In contrast, hyperthermia at 45 0 C increased the slope of the radiation survival curve by a factor of 1.7 for a radiation pretreatment of 10 min at 45 0 C, but only by 1.3 for the same treatment immediately after irradiation. The corresponding D/sub q/'s were 262 and 138 rad, respectively. A combination of 45 and 40 0 C hyperthermia (10 min at 45 0 C + 2 hr at 40 0 C + X) resulted in a superposition of the individual effects of 45 or 40 0 C hyperthermia on the radiation survival curve. In addition, the radiation survival curve was shifted downward by a factor of three due to the potentiation of 45 0 C hyperthermia damage by postincubation at 40 0 C. Repair of sublethal radiation damage was completely suppressed during incubation at 40 following hyperthermia at 45 0 C. However, when cells were returned to 37 0 C, even after 6 hr at 40 following 45 0 C hyperthermia, the capacity to accumulate and repair sublethal radiation damage was immediately restored. These findings imply that the hyperthermia damage from low or high temperatures interacts differentially with radiation damage. Low hyperthermia at 40 0 C may affect principally the radiation repair system, whereas 45 0 C hyperthermia probably alters the radiation target more severely than the repair system

  16. Radiation dose of cone-beam computed tomography compared to conventional radiographs in orthodontics.

    Science.gov (United States)

    Signorelli, Luca; Patcas, Raphael; Peltomäki, Timo; Schätzle, Marc

    2016-01-01

    The aim of this study was to determine radiation doses of different cone-beam computed tomography (CBCT) scan modes in comparison to a conventional set of orthodontic radiographs (COR) by means of phantom dosimetry. Thermoluminescent dosimeter (TLD) chips (3 × 1 × 1 mm) were used on an adult male tissue-equivalent phantom to record the distribution of the absorbed radiation dose. Three different scanning modes (i.e., portrait, normal landscape, and fast scan landscape) were compared to CORs [i.e., conventional lateral (LC) and posteroanterior (PA) cephalograms and digital panoramic radiograph (OPG)]. The following radiation levels were measured: 131.7, 91, and 77 μSv in the portrait, normal landscape, and fast landscape modes, respectively. The overall effective dose for a COR was 35.81 μSv (PA: 8.90 μSv; OPG: 21.87 μSv; LC: 5.03 μSv). Although one CBCT scan may replace all CORs, one set of CORs still entails 2-4 times less radiation than one CBCT. Depending on the scan mode, the radiation dose of a CBCT is about 3-6 times an OPG, 8-14 times a PA, and 15-26 times a lateral LC. Finally, in order to fully reconstruct cephalograms including the cranial base and other important structures, the CBCT portrait mode must be chosen, rendering the difference in radiation exposure even clearer (131.7 vs. 35.81 μSv). Shielding radiation-sensitive organs can reduce the effective dose considerably. CBCT should not be recommended for use in all orthodontic patients as a substitute for a conventional set of radiographs. In CBCT, reducing the height of the field of view and shielding the thyroid are advisable methods and must be implemented to lower the exposure dose.

  17. Inactivation of Coxiella burnetii by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, G.H.; McCaul, T.F. (Army Medical Research Inst. of Infectious Diseases, Fort Detrick, Frederick, MD (USA)); Williams, J.C. (National Inst. of Allergy and Infectious Diseases, Bethesda, MD (USA))

    1989-12-01

    The gamma radiation inactivation kinetics for Coxiella burnetii at - 79{sup 0}C were exponential. The radiation dose needed to reduce the number of infective C. burnetii by 90% varied from 0.64 to 1.2 kGy depending on the phase of the micro-organism, purity of the culture and composition of suspending menstruum. The viability of preparations containing 10{sup 11} C. burnetii ml{sup -1} was completely abolished by 10 kGy without diminishing antigenicity or ability to elicit a protective immune response in vaccinated mice. Immunocytochemical examinations using monoclonal antibodies and electron microscopy demonstrated that radiation doses of 20 kGy did not alter cell-wall morphology or cell-surface antigenic epitopes. (author).

  18. Inactivation of Coxiella burnetii by gamma irradiation

    International Nuclear Information System (INIS)

    Scott, G.H.; McCaul, T.F.; Williams, J.C.

    1989-01-01

    The gamma radiation inactivation kinetics for Coxiella burnetii at - 79 0 C were exponential. The radiation dose needed to reduce the number of infective C. burnetii by 90% varied from 0.64 to 1.2 kGy depending on the phase of the micro-organism, purity of the culture and composition of suspending menstruum. The viability of preparations containing 10 11 C. burnetii ml -1 was completely abolished by 10 kGy without diminishing antigenicity or ability to elicit a protective immune response in vaccinated mice. Immunocytochemical examinations using monoclonal antibodies and electron microscopy demonstrated that radiation doses of 20 kGy did not alter cell-wall morphology or cell-surface antigenic epitopes. (author)

  19. Radiation

    International Nuclear Information System (INIS)

    Winther, J.F.; Ulbak, K.; Dreyer, L.; Pukkala, E.; Oesterlind, A.

    1997-01-01

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  20. Differential effects of simple repeating DNA sequences on gene expression from the SV40 early promoter.

    Science.gov (United States)

    Amirhaeri, S; Wohlrab, F; Wells, R D

    1995-02-17

    The influence of simple repeat sequences, cloned into different positions relative to the SV40 early promoter/enhancer, on the transient expression of the chloramphenicol acetyltransferase (CAT) gene was investigated. Insertion of (G)29.(C)29 in either orientation into the 5'-untranslated region of the CAT gene reduced expression in CV-1 cells 50-100 fold when compared with controls with random sequence inserts. Analysis of CAT-specific mRNA levels demonstrated that the effect was due to a reduction of CAT mRNA production rather than to posttranscriptional events. In contrast, insertion of the same insert in either orientation upstream of the promoter-enhancer or downstream of the gene stimulated gene expression 2-3-fold. These effects could be reversed by cotransfection of a competitor plasmid carrying (G)25.(C)25 sequences. The results suggest that a G.C-binding transcription factor modulates gene expression in this system and that promoter strength can be regulated by providing protein-binding sites in trans. Although constructs containing longer tracts of alternating (C-G), (T-G), or (A-T) sequences inhibited CAT expression when inserted in the 5'-untranslated region of the CAT gene, the amount of CAT mRNA was unaffected. Hence, these inhibitions must be due to posttranscriptional events, presumably at the level of translation. These effects of microsatellite sequences on gene expression are discussed with respect to recent data on related simple repeat sequences which cause several human genetic diseases.

  1. Radiation exposure profile and dose estimates to flyers en route Frankfurt to Mumbai

    International Nuclear Information System (INIS)

    Rao, D.D.; Hegde, A.G.

    2010-01-01

    The earth is continuously bombarded by the high energy radiation (galactic radiation) from solar system commonly known as cosmic radiation. Intensity of cosmic ray radiation exposures change with altitude and increases rapidly with the increase in altitude from the earth. Passenger and cargo flights fly at different altitudes and therefore the crew and passengers are exposed to radiation levels significantly higher than the average background levels on the earth. A typical commercial jet aircraft fly at an altitude of 30,000 - 40,000 feet (9-12 km) and at these heights radiation exposure rates increase by about 100 times from the background levels. European countries have guidelines and suggestions on radiation exposure to air crew members in sectors that may potentially expose them to levels exceeding 1 mSv per annum. The paper details the radiation exposure profile recorded in Frankfurt-Dubai-Mumbai sector and evaluation of average radiation exposure received by the flyers and air crew members

  2. A novel splice variant of supervillin, SV5, promotes carcinoma cell proliferation and cell migration

    International Nuclear Information System (INIS)

    Chen, Xueran; Yang, Haoran; Zhang, Shangrong; Wang, Zhen; Ye, Fang; Liang, Chaozhao; Wang, Hongzhi; Fang, Zhiyou

    2017-01-01

    Supervillin is an actin-associated protein that regulates actin dynamics by interacting with Myosin II, F-actin, and Cortactin to promote cell contractility and cell motility. Two splicing variants of human Supervillin (SV1 and SV4) have been reported in non-muscle cells; SV1 lacks 3 exons present in the larger isoform SV4. SV2, also called archvillin, is present in striated muscle; SV3, also called smooth muscle archvillin or SmAV, was cloned from smooth muscle. In the present study, we identify a novel splicing variant of Supervillin (SV5). SV5 contains a new splicing pattern. In the mouse tissues and cell lines examined, SV5 was predominantly expressed in skeletal and cardiac muscles and in proliferating cells, but was virtually undetectable in most normal tissues. Using RNAi and rescue experiments, we show here that SV5 displays altered functional properties in cancer cells, and regulates cell proliferation and cell migration.

  3. Natural radiation doses for cosmic and terrestrial components in Costa Rica

    International Nuclear Information System (INIS)

    Mora, Patricia; Picado, Esteban; Minato, Susumu

    2007-01-01

    A study of external natural radiation, cosmic and terrestrial components, was carried out with in situ measurements using NaI scintillation counters while driving along the roads in Costa Rica for the period July 2003-July 2005. The geographical distribution of the terrestrial air-absorbed dose rates and the total effective dose rates (including cosmic) are represented on contour maps. Information on the population density of the country permitted the calculation of the per capita doses. The average effective dose for the total cosmic component was 46.88±18.06 nSv h -1 and the average air-absorbed dose for the terrestrial component was 29.52±14.46 nGy h -1 . The average total effective dose rate (cosmic plus terrestrial components) was 0.60±0.18 mSv per year. The effective dose rate per capita was found to be 83.97 nSv h -1 which gives an annual dose of 0.74 mSv. Assuming the world average for the internal radiation component, the natural radiation dose for Costa Rica will be 2.29 mSv annually

  4. Radiation doses from radon and progeny in Irish houses

    International Nuclear Information System (INIS)

    McLaughlin, J.P.

    1985-08-01

    In the United Kingdom, the estimated average annual effective dose equivalent to members of the public from all sources is 2.4 mSv (240 mrem). 40% of this dose is contributed by exposure to radon, and it is not unreasonable to assume that the situation in Ireland is very similar. During 1982-84 a preliminary study of radon and penetrating radiation on 300 Irish houses showed seasonally averaged indoor radon concentrations in the range 3 Bq/m 3 of air to 700 bq/m 3 , with a median value of about 40 bq/m 3 . A national survey of indoor radon has now been undertaken; 3000 households, randomly selected from the electoral register are to be monitored and the result correlated with energy conservation practices. The final part of this document deals with the regulatory aspects of radon control and reviews the practices for reduction of indoor radon daughter doses presently in hand in Scandinavia. An appendix of radiation units and terms is also given

  5. Chronic low dose radiation exposure and oxidative stress in radiation workers

    International Nuclear Information System (INIS)

    Ali, S.S.; Bhatt, M.B.; Kulkarni, MM.; Rajan, R.; Singh, B.B.; Venkataraman, G.

    1996-01-01

    Free radicals have been implicated in the pathogenesis of several human diseases. In this study free radical stress due to low dose chronic radiation exposures of radiation workers was examined as a possible atherogenic risk factor. Data on lipid profiles, lipid peroxidation and reduced glutathione content in blood indicated an absence of correlation with radiation doses up to 125 mSv. (author). 13 refs., 1 fig

  6. Stimulation of NADH-dependent microsomal DNA strand cleavage by rifamycin SV.

    OpenAIRE

    Kukiełka, E; Cederbaum, A I

    1995-01-01

    Rifamycin SV is an antibiotic anti-bacterial agent used in the treatment of tuberculosis. This drug can autoxidize, especially in the presence of metals, and generate reactive oxygen species. A previous study indicated that rifamycin SV can increase NADH-dependent microsomal production of reactive oxygen species. The current study evaluated the ability of rifamycin SV to interact with iron and increase microsomal production of hydroxyl radical, as detected by conversion of supercoiled plasmid...

  7. Review of the controversy on risks from low levels of radiation

    International Nuclear Information System (INIS)

    Higson, D.

    2001-01-01

    The need for regulation of low levels of radiation exposure, and the estimation of risks from such exposures, are based on the assumption that risk is proportional to dose without a threshold, the 'linear no-threshold (LNT) hypothesis'. This assumption is not supported by scientific data. There is no clear evidence of harm from low levels of exposure, up to at least 20 mSv (acute dose) or total dose rates of at least 50 mSv per year. Even allowing for reasonable extrapolation from radiation levels at which harmful effects have been observed, the LNT assumption should not be used to estimate risks from doses less than 100 mSv. Laboratory and epidemiological evidence, and evolutionary expectations of biological effects from low level radiation, suggest that beneficial health effects (sometimes called 'radiation hormesis') are at least as likely as harmful effects from such exposures. Controversy on this matter strikes at the basis of radiation protection practice

  8. Development of direct reading dosimeters for the dose 0-3 mSv and 0-5 mSv ranges for personnel monitoring

    International Nuclear Information System (INIS)

    Gaikwad, P.V.; Shirkar, Y.B.; Patil, A.S.; Madgaonkar, P.P.; Kale, K.L.; Guhagarkar, H.V.; Gandhi, D.P.; Gupta, S.K.; Kothiyal, G.P.; Sahni, V.C.

    1998-01-01

    Direct reading dosimeters (DRDs) are widely used to measure cumulative dose received by personnel working at nuclear reactor sites or in other environment having x- and gamma rays. A DRD operates on the principle of gold leaf electroscope, and is a small, rugged, hermetically sealed, self reading type device easily carried by an individual in his pocket. The development of dosimeters suitable for the dose ranges 0-3 mSv and 0-5 mSv is reported

  9. Radiation protection measures for hot cell sanitation

    International Nuclear Information System (INIS)

    Berger, H.U.; Burck, W.; Dilger, H.

    1983-01-01

    The cell 5 of the Hot Cell Facility of the Kernforschungszentrum Karlsruhe GmbH (KfK) was to be restored and reequipped after 12 years of operation. The decontamination work was first done remotely controlled and afterwards by 38 persons entering the cell, which took about 2 months. The radiation protection methods and personal dosimetry systems are described. At the beginning of the work the γ-dose rate amounted up to 900 mSv/h. After completion of the remotely controlled decontamination work the γ-dose rate decreased to 1.5 mSv/h. At that time the (α+β-contamination was 10 5 Bq/cm 2 . Till the end of the work the removable activity dropped to 10 2 - 10 3 Bq/cm 2 for β-radiation, to 0.3 - 30 Bq/cm 2 for α-radiation and the local dose rate to about 0.03 mSv/h. During the work the accumulated collective doses were listed for breast, hand, head, gonads and foot. In the figure the development with the time of the doses for breast and hand is shown. During restoration work of the cell the accumulated collective whole-body dose amounted to 30 mSv. (orig.) [de

  10. NATURAL RADIOACTIVITY LEVEL AND ELEMENTAL COMPOSITION OF SOIL SAMPLES FROM A HIGH BACKGROUND RADIATION AREA ON EASTERN COAST OF INDIA (ODISHA).

    Science.gov (United States)

    Sahoo, S K; Kierepko, R; Sorimachi, A; Omori, Y; Ishikawa, T; Tokonami, S; Prasad, G; Gusain, G S; Ramola, R C

    2016-10-01

    A comprehensive study was carried out to determine the radioactivity concentration of soil samples from different sites of a high background radiation area in the eastern coast of India, Odisha state. The dose rate measured in situ varied from 0.25 to 1.2 µSv h -1 The gamma spectrometry measurements indicated Th series elements as the main contributors to the enhanced level of radiation and allowed the authors to find the mean level of the activity concentration (±SD) for 226 Ra, 228 Th and 40 K as 130±97, 1110±890 and 360±140 Bq kg -1 , respectively. Human exposure from radionuclides occurring outdoor was estimated based on the effective dose rate, which ranged from 0.14±0.02 to 2.15±0.26 mSv and was higher than the UNSCEAR annual worldwide average value 0.07 mSv. Additionally, X-ray fluorescence analysis provided information about the content of major elements in samples and indicated the significant amount of Ti (7.4±4.9 %) in soils. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Impact of a Disposable Sterile Radiation Shield on Operator Radiation Exposure During Percutaneous Coronary Intervention of Chronic Total Occlusions.

    Science.gov (United States)

    Shorrock, Deborah; Christopoulos, Georgios; Wosik, Jedrek; Kotsia, Anna; Rangan, Bavana; Abdullah, Shuaib; Cipher, Daisha; Banerjee, Subhash; Brilakis, Emmanouil S

    2015-07-01

    Daily radiation exposure over many years can adversely impact the health of medical professionals. Operator radiation exposure was recorded for 124 percutaneous coronary interventions (PCIs) performed at our institution between August 2011 and May 2013: 69 were chronic total occlusion (CTO)-PCIs and 55 were non-CTO PCIs. A disposable radiation protection sterile drape (Radpad; Worldwide Innovations & Technologies, Inc) was used in all CTO-PCI cases vs none of the non-CTO PCI cases. Operator radiation exposure was compared between CTO and non-CTO PCIs. Mean age was 64.6 ± 6.2 years and 99.2% of the patients were men. Compared with non-CTO PCI, patients undergoing CTO-PCI were more likely to have congestive heart failure, to be current smokers, and to have longer lesions, and less likely to have prior PCI and a saphenous vein graft target lesion. CTO-PCI cases had longer procedural time (median: 123 minutes [IQR, 85-192 minutes] vs 27 minutes [IQR, 20-44 minutes]; P<.001), fluoroscopy time (35 minutes [IQR, 19-54 minutes] vs 8 minutes [IQR, 5-16 minutes]; P<.001), number of stents placed (2.4 ± 1.5 vs 1.7 ± 0.9; P<.001), and patient air kerma radiation exposure (3.92 Gray [IQR, 2.48-5.86 Gray] vs 1.22 Gray [IQR, 0.74-1.90 Gray]; P<.001), as well as dose area product (267 Gray•cm² [IQR, 163-4.25 Gray•cm²] vs 84 Gray•cm² [IQR, 48-138 Gray•cm²]; P<.001). In spite of higher patient radiation exposure, operator radiation exposure was similar between the two groups (20 μSv [IQR, 9.5-31 μSv] vs 15 μSv [IQR, 7-23 μSv]; P=.07). Operator radiation exposure during CTO-PCI can be reduced to levels similar to less complicated cases with the use of a disposable sterile radiation protection shield.

  12. Ionizing radiation, genetic risks and radiation protection

    International Nuclear Information System (INIS)

    Sankaranarayanan, K.

    1992-01-01

    With one method of risk estimation, designed as the doubling dose method, the estimates of total genetic risk (i.e., over all generation) for a population continuously exposed at a rate of 0.01 Gy/generation of low LET irradiation are about 120 cases of Mendelian and chromosomal diseases/10 6 live births and about the same number of cases for multifactorial diseases (i.e., a total of 240 cases/10 6 ). These estimates provide the basis for risk coefficients for genetic effects estimated by ICRP (1991) in its Publication 60. These are: 1.0%/Sv for the general population (which is 40% of 240/10 6 /0.01 Gy), and 0.6%/Sv for radiation workers (which is 60% of that for the general population). The results of genetic studies carried out on the Japanese survivors of A-bombs have shown no significant adverse effects attributable to parental radiation exposures. The studies of Gardner and colleagues suggest that the risk of leukaemia in children born to male workers in the nuclear reprocessing facility in Sellafield, U.K., may be increased. However, this finding is at variance with the results from the Japanese studies and at present, does not lend itself to a simple interpretation based on radiobiological principles. In the light of recent advances in the molecular biology of naturally-occurring human Mendelian diseases and what we presently know about multifactorial diseases, arguments are advanced to support the thesis that (i) current risk estimates for Mendelian diseases may be conservative and (ii) an overall doubling dose for all adverse genetic effects may be higher than the 1 Gy currently used (i.e., the relative risks are probably lower). (author)

  13. The Efficiency of UVC Radiation in the Inactivation of Listeria monocytogenes on Beef-Agar Food Models

    Directory of Open Access Journals (Sweden)

    Christian James

    2015-01-01

    Full Text Available The aim of this study is to evaluate the eff ect of meat content and surface smoothness on the deactivation of Listeria monocytogenes in beef-agar food models achieved by shortwave ultraviolet (UVC light. Food models with various meat contents were made using chopped beef slices and agar solution. Prepared models together with a Listeria selective agar (LSA plate and a slice of cooked beef were inoculated with L. monocytogenes and then exposed to UVC light. Population of Listeria reduced to below the level of detection on the LSA plates. As the content of beef in the beef-agar models increased, more L. monocytogenes cells survived. Survival was greatest on the treated cooked slice of beef. To bett er understand the effect of surface irregularities, a white light interferometer was used to analyse the surface smoothness of beef-agar media and LSA plates. No correlation was observed between the surface roughness of seven out of nine types of produced beef-agar media and the degree of inactivation resulting from UVC radiation at the given dose, whereas, less bacterial cells were killed as beef content of the food models increased. The findings of the current study show that the chemical composition of the treated sample also plays an important role in pathogen resistance and survival, meaning that two samples with similar surface irregularities but diff erent chemical composition might produce very diff erent inactivation results when exposed to UVC light.

  14. Structure-based design of a disulfide-linked oligomeric form of the simian virus 40 (SV40) large T antigen DNA-binding domain

    International Nuclear Information System (INIS)

    Meinke, Gretchen; Phelan, Paul; Fradet-Turcotte, Amélie; Archambault, Jacques; Bullock, Peter A.

    2011-01-01

    With the aim of forming the ‘lock-washer’ conformation of the origin-binding domain of SV40 large T antigen in solution, using structure-based analysis an intermolecular disulfide bridge was engineered into the origin-binding domain to generate higher order oligomers in solution. The 1.7 Å resolution structure shows that the mutant forms a spiral in the crystal and has the de novo disulfide bond at the protein interface, although structural rearrangements at the interface are observed relative to the wild type. The modular multifunctional protein large T antigen (T-ag) from simian virus 40 orchestrates many of the events needed for replication of the viral double-stranded DNA genome. This protein assembles into single and double hexamers on specific DNA sequences located at the origin of replication. This complicated process begins when the origin-binding domain of large T antigen (T-ag ODB) binds the GAGGC sequences in the central region (site II) of the viral origin of replication. While many of the functions of purified T-ag OBD can be studied in isolation, it is primarily monomeric in solution and cannot assemble into hexamers. To overcome this limitation, the possibility of engineering intermolecular disulfide bonds in the origin-binding domain which could oligomerize in solution was investigated. A recent crystal structure of the wild-type T-ag OBD showed that this domain forms a left-handed spiral in the crystal with six subunits per turn. Therefore, we analyzed the protein interface of this structure and identified two residues that could potentially support an intermolecular disulfide bond if changed to cysteines. SDS–PAGE analysis established that the mutant T-ag OBD formed higher oligomeric products in a redox-dependent manner. In addition, the 1.7 Å resolution crystal structure of the engineered disulfide-linked T-ag OBD is reported, which establishes that oligomerization took place in the expected manner

  15. Computed tomography to diagnose coronary artery disease: A reduction in radiation dose increases applicability

    International Nuclear Information System (INIS)

    Gosling, O.; Morgan-Hughes, G.; Iyengar, S.; Strain, W.; Loader, R.; Shore, A.; Roobottom, C.

    2013-01-01

    Aim: To assess the effects of dose-saving algorithms on the radiation dose in an established computed tomography coronary angiography (CTCA) clinical service. Materials and methods: A 3 year retrospective analysis of all patients attending for a clinically indicated CTCA was performed. The effective dose was calculated using a cardiac-specific conversion factor [0.028 mSv(mGy·cm) −1 ]. Patients were stratified by the advent of new scanning technology and dose-saving protocols. Results: Between September 2007 and August 2010, 1736 examinations were performed. In the first 6 months, 150 examinations were performed with a mean effective dose of 29.6 mSv (99% CI 26.6–33 mSv). In March 2008 prospective electrocardiogram (ECG) gating was installed; reducing the effective dose to 13.6 mSv (99% CI 12.5–14.9 mSv). In March 2009, the scanner parameters were set to a minimal exposure time and 100 kV in patients with a body mass index (BMI) of <30. This reduced the mean dose to 7.4 mSv (99% CI 6.8–8 mSv). For the final six months the mean radiation dose for a cardiac scan was 5.9 mSv (99% CI 5.4–6.5 mSv) this figure incorporates all examinations performed irrespective of the protocol used. Conclusion: With the implementation of evidence-based protocols, the effective dose from cardiac CT has significantly reduced. As CTCA services develop dose-saving algorithms should be adopted to keep the radiation dose as low as reasonably practical

  16. Initiation of simian virus 40 DNA replication in vitro: Pulse-chase experiments identify the first labeled species as topologically unwound

    International Nuclear Information System (INIS)

    Bullock, P.A.; Seo, Yeon Soo; Hurwitz, J.

    1989-01-01

    A distinct unwound form of DNA containing the simian virus 40 (SV40) origin is produced in replication reactions carried out in mixtures containing crude fractions prepared from HeLa cells. This species, termed form U R , comigrates on chloroquine-containing agarose gels with the upper part of the previously described heterogeneous highly unwound circular DNA, form U. As with form U, formation of form U R is dependent upon the SV40 tumor (T) antigen. Pulse-chase experiments demonstrate that the first species to incorporate labeled deoxyribonucleotides comigrates with form U R . Restriction analyses of the products of the pulse-chase experiments show that initiation occurs at the SV40 origin and then proceeds outward in a bidirectional manner. These experiments establish form U R as the earliest detectable substrate for SV40 DNA replication and suggest that SV40 DNA replication initiates on an unwound species

  17. Protocol for Determining Ultraviolet Light Emitting Diode (UV-LED) Fluence for Microbial Inactivation Studies.

    Science.gov (United States)

    Kheyrandish, Ataollah; Mohseni, Madjid; Taghipour, Fariborz

    2018-06-15

    Determining fluence is essential to derive the inactivation kinetics of microorganisms and to design ultraviolet (UV) reactors for water disinfection. UV light emitting diodes (UV-LEDs) are emerging UV sources with various advantages compared to conventional UV lamps. Unlike conventional mercury lamps, no standard method is available to determine the average fluence of the UV-LEDs, and conventional methods used to determine the fluence for UV mercury lamps are not applicable to UV-LEDs due to the relatively low power output, polychromatic wavelength, and specific radiation profile of UV-LEDs. In this study, a method was developed to determine the average fluence inside a water suspension in a UV-LED experimental setup. In this method, the average fluence was estimated by measuring the irradiance at a few points for a collimated and uniform radiation on a Petri dish surface. New correction parameters were defined and proposed, and several of the existing parameters for determining the fluence of the UV mercury lamp apparatus were revised to measure and quantify the collimation and uniformity of the radiation. To study the effect of polychromatic output and radiation profile of the UV-LEDs, two UV-LEDs with peak wavelengths of 262 and 275 nm and different radiation profiles were selected as the representatives of typical UV-LEDs applied to microbial inactivation. The proper setup configuration for microorganism inactivation studies was also determined based on the defined correction factors.

  18. Susceptibility of Campylobacter jejuni and Yersinia enterocolitica to UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Butler, R.C.; Lund, V.; Carlson, D.A.

    1987-02-01

    Two enteric pathogens, Campylobacter jejuni and Yersinia enterocolitica serogroup O:3, together with Escherichia coli, were investigated for susceptibility to UV radiation at 254 nm. The UV dose required for a 3-log reduction (99.9% inactivation) of C. jejuni, Y. enterocolitica, and E. coli was 1.8, 2.7, and 5.0 mWs/cm2, respectively. Using E. coli as the basis for comparison, it appears that C. jejuni and Y. enterocolitica serogroup O:3 are more sensitive to UV than many of the pathogens associated with waterborne disease outbreaks and can be easily inactivated in most commercially available UV reactors. No association was found between the sensitivity of Y. enterocolitica to UV and the presence of a 40- to 50-megadalton virulence plasmid.

  19. Susceptibility of Campylobacter jejuni and Yersinia enterocolitica to UV radiation

    International Nuclear Information System (INIS)

    Butler, R.C.; Lund, V.; Carlson, D.A.

    1987-01-01

    Two enteric pathogens, Campylobacter jejuni and Yersinia enterocolitica serogroup O:3, together with Escherichia coli, were investigated for susceptibility to UV radiation at 254 nm. The UV dose required for a 3-log reduction (99.9% inactivation) of C. jejuni, Y. enterocolitica, and E. coli was 1.8, 2.7, and 5.0 mWs/cm2, respectively. Using E. coli as the basis for comparison, it appears that C. jejuni and Y. enterocolitica serogroup O:3 are more sensitive to UV than many of the pathogens associated with waterborne disease outbreaks and can be easily inactivated in most commercially available UV reactors. No association was found between the sensitivity of Y. enterocolitica to UV and the presence of a 40- to 50-megadalton virulence plasmid

  20. Inactivation of carbenicillin by some radioresistant mutant strains

    International Nuclear Information System (INIS)

    Zahiera, T.S.; Mahmoud, M.I.; Bashandy, A.A.

    1990-01-01

    Sensitivity test of five bacterial species to carbenicillin was performed microbiologically. The bacterial species were previously isolated from high level radiation environment. All the studied species could either highly decrease the antibiotic activity or even inactivate it completely. Detailed study of the inactivation of carbenicillin by the radioresistant mutant strains B. Laterosporus, B. firmus and M. roseus was performed, in the present study. Using high performace liquid chromatography technique. The gram-positive m. roseus mutant strain seemed to be the most active mutant in degrading the antibiotic. The left over of the antibiotic attained a value of 9% of the original amount after 14 day incubation of the antibiotic with this mutant strain, while the value of the left over reached 36% and 32% after the same period of incubation with the mutants B. laterosporus and B. firmus respectively. In the case of bacillus species, the degradation of the antibiotic started at the same moment when it was added to the bacterial cultures. This fact may indicate that the inactivation of the studied antibiotic by these bacillus species was due to extracellular enzymes extracted rapidly in the surrounding medium. In the case of M. roseus the inactivation process started later. after the addition of the antibiotic to the mutant culture

  1. LOW PRESSURE ULTRAVIOLET STUDIES FOR INACTIVATION OF GIARDIA MURIS CYSTS

    Science.gov (United States)

    This research was initiated to confirm and expand the current database for the inactivation of Giardia spp. using ultraviolet (UV) radiation. Initially, previous research that used in vitro excystation as the indicator for UV effectiveness was confirmed. Later, the in vitro excys...

  2. Radiation exposure for medical staff performing quantitative coronary perfusion PET with 13N-ammonia

    DEFF Research Database (Denmark)

    Kristoffersen, Ulrik Sloth; Borgwardt, Henrik Gutte; Skovgaard, Dorthe Charlotte

    2009-01-01

    with dipyridamole) and eight examinations consisted of three PET scans (additionally a scan after cold pressor testing). The two nuclear technologists and the physician attending the examinations were equipped with an electronic dosemeter over the chest and thermoluminescent dosimetry chips on the right index...... finger and wrist. RESULTS: The highest mean equivalent dose per examination for a staff member was 453 microSv (417-490 microSv) to the right index finger, 138 microSv (127-149 microSv) to the right wrist and 13 +/- 0.8 microSv to the chest. CONCLUSIONS: Myocardial perfusion PET with (13)N......-ammonia exposes the staff to radiation doses that are comparable to doses from (18)F-fluoro-deoxy-glucose scans and the annual doses are well within the recommended upper limits for radiation workers....

  3. Medical management of three workers following a radiation exposure incident

    International Nuclear Information System (INIS)

    House, R.A.; Sax, S.E.; Rumack, E.R.; Holness, D.L.

    1992-01-01

    The medical management of three individuals involved in an exposure incident to whole-body radiation at a nuclear generating plant of a Canadian electrical utility is described. The exposure incident resulted in the two highest whole-body radiation doses ever received in a single event by workers in a Canadian nuclear power plant. The individual whole-body doses (127.4 mSv, 92.0 mSv, 22.4 mSv) were below the threshold for acute radiation sickness but the exposures still presented medical management problems related to assessment and counseling. Serial blood counting and lymphocyte cytogenetic analysis to corroborate the physical dosimetry were performed. All three employees experienced somatic symptoms due to stress and one employee developed post-traumatic stress disorder. This incident indicates that there is a need in such radiation exposure accidents for early and continued counseling of exposed employees to minimize the risk of development of stress-related symptoms

  4. Medical management of three workers following a radiation exposure incident

    Energy Technology Data Exchange (ETDEWEB)

    House, R.A.; Sax, S.E.; Rumack, E.R.; Holness, D.L. (Department of Occupational and Environmental Health, St. Michael' s Hospital, Toronto, Ontario (Canada))

    1992-01-01

    The medical management of three individuals involved in an exposure incident to whole-body radiation at a nuclear generating plant of a Canadian electrical utility is described. The exposure incident resulted in the two highest whole-body radiation doses ever received in a single event by workers in a Canadian nuclear power plant. The individual whole-body doses (127.4 mSv, 92.0 mSv, 22.4 mSv) were below the threshold for acute radiation sickness but the exposures still presented medical management problems related to assessment and counseling. Serial blood counting and lymphocyte cytogenetic analysis to corroborate the physical dosimetry were performed. All three employees experienced somatic symptoms due to stress and one employee developed post-traumatic stress disorder. This incident indicates that there is a need in such radiation exposure accidents for early and continued counseling of exposed employees to minimize the risk of development of stress-related symptoms.

  5. The automatic radiation monitor distributed System SRM-256C

    International Nuclear Information System (INIS)

    Stetsenko, G.N.; Rastsvetalov, Y.N.; Yanovich, A.A.

    1996-01-01

    The Controlled and Supervised Areas (CSA) of UNK proton accelerator built in Protvino (IHEP, Russia), borrows the significant area (more than 15 sq.km). Submitted in work results of accounts show, that by major factors, influencing to a radioecological conditions in region at the expense of work UNK are: 1) the output of pulsing radiation on day-time surface; 2) the radionuclides receipts with drinking water; 3) the pollution of radioactive air from system of ventilation. At normal mode of UNK operation the equivalent dose rates on daytime surface of pulsing radiation will changes in limits from 0.5 mcSv/hours near overmines buildings up to 0.1 mcSv / hour on the CSA border. The average equivalent dose rates per year due to internal irradiation at use (intakes) of drinking water will not exceed 5 - 50 mcSv/years. The Maximum equivalent dose rates on day-time surface, caused by pollution of radioactive air does not exceed 0.01... 0.03 mcSv/hour in limits of CSA, and the average equivalent dose per year caused by internal irradiation does not exceed 0.05 mcSv/years. At emergency-free operation the maximum degree of the UNK influence in limits of CSA is estimated in terms of average equivalent dose per year at levels, not exceeding 0.05... 0.10 mSv/year. For maintenance of integral environmental monitoring of total external radiation levels in limits of CSA network of passive monitor stations will be developed

  6. Sensitivity of viruses to radiation sterilization

    International Nuclear Information System (INIS)

    Dziedzic Goclawska; A

    1999-01-01

    The hazard of infectious disease transmission with tissue allografts is a major concern in tissue banking practice. Microorganisms can be introduced into grafts during tissue collection, processing and storage, but even when all these procedures are performed under a septic conditions, the possibility of fungal, bacterial or viral disease transmission of donor origin can not be excluded. Therefore, in order to minimize the risk of infectious disease transmission, several steps should be undertaken, including a careful donor screening, proper tissue processing and sterilization of tissue allografts. The risk of transmission of viral infections such as hepatitis B, C, other viruses and particularly HIV with tissue allografts is of great significance and the search for sterilizing methods which inactivate and/or highly reduce viral infectivity continues. Sterilization of tissue allografts with ionizing radiation (introduced in the mid of 1950s) is increasingly used in tissue banking practice. The effectiveness of the radiation-sterilization procedure depends on the amount of energy transferred, the number of contaminating microorganisms and their resistance to ionizing radiation (initial contamination, bioburden). Usually, spores are more resistant than vegetative forms of bacteria, some fungi may be as resistant as bacterial spores, and viruses are, in general, more resistant than bacteria. Dita concerning effectiveness of ionizing radiation to inactivate viruses (e.g. such as HBV, HCV or HIV) in tissue allografts collected from cadavers are scarce. It has been found that the dose of irradiation needed to reduce HIV load by I log10 unit (D10) is about 4.0 kGy or even 5.6 kGy. The level of infectious HIV in plasma is usually evaluated by titration of tissue culture infective dose (TCID50/ml). Taking into consideration the recommended sterility assurance level (SAL) 10-6, assuming the HIV bioburden to be 103 TCID50/ml for the state of acute infection and D10 value of 4

  7. A proposal for a radiation protection scale to better communicate with the public

    International Nuclear Information System (INIS)

    Mueck, Konrad; Balonov, Michail; Bayer, Anton; Burkart, Klaus; Brunner, Hans H.; Drabova, Dana; Rousseau, Denys; Hu Zunsu

    2000-01-01

    A major problem in the communication of radiation protection experts with the public is misunderstanding of radiation protection concepts and the various units used in radiation protect which tend to confuse the public. Another problem to inability of the public to differentiate between low, medium and high doses and their possible implications. Also the public and the media are not able to comprehend the differences between units and subunits (Sv, mSv, μSv, etc.). Therefore, a simple, for the general citizen easily understandable scale for the radiation exposure of human beings is proposed which should assist in making radiation exposure values and their consequences to health more easily understandable for the general public. The logarithmic setup of the scale yields an easily understandable scale of integer numbers from 1 to 7 where the levels 0 - 3 of the scale describe the dose range of minuscule dose values below natural radiation exposure levels, level 4 the dose range of 1 - 10 mSv, i.e. the dose range of the natural radiation exposure, while level 6 and 7 define the dose range 0.1 to 1 Sv and above 1 Sv in which protective measures to reduce the dose are important or absolutely required to avoid significant effects for the concerned individuals. In the approach to facilitate the comprehension by less knowledgeable persons, the proposed radiation protection scale is comparable to other scales (INES-scale, RICHTER-scale) where events of a wide range from practically no consequences via observable effects to severe consequences are given in an understandable 'risk-scale'. In the opinion of the authors the scale would facilitate the comprehension of the public why for a given dose no action to reduce it is considered and for another dose level dose reduction measures are recommended or absolutely required. The radiation protection scale should also lead to easily understandable risk factors in an environment where radiation is considered by the public and the

  8. Photodynamic inactivation of conidia of the fungus Colletotrichum abscissum on Citrus sinensis plants with methylene blue under solar radiation.

    Science.gov (United States)

    Gonzales, Júlia C; Brancini, Guilherme T P; Rodrigues, Gabriela B; Silva-Junior, Geraldo José; Bachmann, Luciano; Wainwright, Mark; Braga, Gilberto Ú L

    2017-11-01

    Antimicrobial photodynamic treatment (APDT) is a promising light based approach to control diseases caused by plant-pathogenic fungi. In the present study, we evaluated the effects of APDT with the phenothiazinium photosensitizer methylene blue (MB) under solar radiation on the germination and viability of conidia of the pathogenic fungus Colletotricum abscissum (former Colletotrichum acutatum sensu lato). Experiments were performed both on petals and leaves of sweet orange (Citrus sinensis) in different seasons and weather conditions. Conidial suspensions were deposited on the leaves and petals surface, treated with the PS (25 or 50μM) and exposed to solar radiation for only 30min. The effects of APDT on conidia were evaluated by counting the colony forming units recovered from leaves and petals and by direct evaluating conidial germination on the surface of these plant organs after the treatment. To better understand the mechanistic of conidial photodynamic inactivation, the effect of APDT on the permeability of the conidial plasma membrane was assessed using the fluorescent probe propidium iodide (PI) together with flow cytometry and fluorescence microscopy. APDT with MB and solar exposure killed C. abscissum conidia and prevented their germination on both leaves and petals of citrus. Reduction of conidial viability was up to three orders of magnitude and a complete photodynamic inactivation was achieved in some of the treatments. APDT damaged the conidial plasma membrane and increased its permeability to PI. No damage to sweet orange flowers or leaves was observed after APDT. The demonstration of the efficacy of APDT on the plant host represents a further step towards the use of the method for control phytopathogens in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. The content of 226Ra, 210Pb, 210Po and 40K on tobacco of some cigarette brands were sold in Bandung, West Java

    International Nuclear Information System (INIS)

    Putu Sukmabuana

    2016-01-01

    This study on the measurements of 226 Ra, 210 Pb, 210 Po and 40 K natural radionuclides contained in tobacco smoke, in order to estimate the effective dose received by smoker has been carried out. The samples have been measured covering 14 brands of cigarettes are commonly sold and consumed in Indonesia. After the tobacco is dried and mashed, the concentration of 226 Ra, 210 Pb and 40 K counted using γ-ray spectrometry, for 80,000 seconds. It was obtained that the average concentration of 226 Ra was 4.18 ± 0.67 Bq/kg, for 210 Pb was 4.71 ± 0.82 Bq/kg, while the average concentration of 40 K was 26.50 ± 2.08 Bq/kg. 210 Po calculated based on radioactive equilibrium, the result was 4.09 ± 0.71 Bq/kg. By using a dose coefficients given by ICRP, the estimated annual effective dose received by the smoker was calculated. The average annual effective dose for 226 Ra was 80.46 ± 12.93 µSv/year, for 210 Pb was 28.47 ± 4.96 µSv/year, and 210 Po was 74.31 ± 12.96 µSv/year. Estimated effective dose for 40 K radionuclide can not be done because the dose coefficients for 40 K is not available in ICRP 71. By summing the average dose of 226 Ra, 210 Pb and 210 Po, obtained total effective dose estimated annual average was 183.24 µSv/year or around 14,5 % of the dose limit for radiation exposure by inhalation in the world (1260 µSv/year). In summary the effective dose above is still relatively small, but nevertheless when radioactive substances and chemicals in cigarette smoke enters the bloodstream it can affect the entire body. This is why smoking causes so many diseases, including cancer, heart disease and various lung diseases. (author)

  10. A comparative study of natural 40K content estimated through whole body counting and dietary intake around Narora Atomic Power Station

    International Nuclear Information System (INIS)

    Gautam, Y.P.; Dube, B.; Hegde, A.G.

    2005-01-01

    773 radiation workers at NAPS, aged 20 to 59 years, were monitored using Shadow Shield Whole Body Counting System having NaI (Tl) crystal coupled with NETS-3 1 K Multi Channel Analyser (MCA) to determine the 40 K activity in the body and assess internal dose due to naturally occurring 40 K. The data have been segregated to make analyses for vegetarian and non-vegetarian. The average annual dose from 40 K for the subjects is evaluated as 156.4 ± 36.1 mSv. Natural 40 K content in 463 environmental samples collected from Narora environ estimated using NaI(Tl) well type detector coupled with 1 K NETS-3 Multichannel analyser (MCA). Assessment of daily intake of natural 40 K has been estimated from average daily intake of dietary items and the associated 40 K activity. It works out to be 67.17 ± 16.28 Bq/d and that obtained through analysis of complete meal samples was 73.22 ± 9.78 Bq/ d. The average annual dose to a member of public of this region due to natural 40 K through ingestion route works out to be 152.12 ± 36.83 mSv/year. (author)

  11. Automated tube voltage selection for radiation dose and contrast medium reduction at coronary CT angiography using 3{sup rd} generation dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Schoepf, U.J. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Poole, Zachary B.; Varga-Szemes, Akos; De Cecco, Carlo N. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Canstein, Christian [Siemens Medical Solutions, Malvern, PA (United States); Caruso, Damiano [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Radiological Sciences, Oncology and Pathology, Rome (Italy); Bamberg, Fabian; Nikolaou, Konstantin [Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany)

    2016-10-15

    To investigate the relationship between automated tube voltage selection (ATVS) and body mass index (BMI) and its effect on image quality and radiation dose of coronary CT angiography (CCTA). We evaluated 272 patients who underwent CCTA with 3{sup rd} generation dual-source CT (DSCT). Prospectively ECG-triggered spiral acquisition was performed with automated tube current selection and advanced iterative reconstruction. Tube voltages were selected by ATVS (70-120 kV). BMI, effective dose (ED), and vascular attenuation in the coronary arteries were recorded. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Five-point scales were used for subjective image quality analysis. Image quality was rated good to excellent in 98.9 % of examinations without significant differences for proximal and distal attenuation (all p ≥.0516), whereas image noise was rated significantly higher at 70 kV compared to ≥100 kV (all p <.0266). However, no significant differences were observed in SNR or CNR at 70-120 kV (all p ≥.0829). Mean ED at 70-120 kV was 1.5 ± 1.2 mSv, 2.4 ± 1.5 mSv, 3.6 ± 2.7 mSv, 5.9 ± 4.0 mSv, 7.9 ± 4.2 mSv, and 10.7 ± 4.1 mSv, respectively (all p ≤.0414). Correlation analysis showed a moderate association between tube voltage and BMI (r =.639). ATVS allows individual tube voltage adaptation for CCTA performed with 3{sup rd} generation DSCT, resulting in significantly decreased radiation exposure while maintaining image quality. (orig.)

  12. Current worldwide nuclear cardiology practices and radiation exposure: results from the 65 country IAEA Nuclear Cardiology Protocols Cross-Sectional Study (INCAPS)

    Science.gov (United States)

    Einstein, Andrew J.; Pascual, Thomas N. B.; Mercuri, Mathew; Karthikeyan, Ganesan; Vitola, João V.; Mahmarian, John J.; Better, Nathan; Bouyoucef, Salah E.; Hee-Seung Bom, Henry; Lele, Vikram; Magboo, V. Peter C.; Alexánderson, Erick; Allam, Adel H.; Al-Mallah, Mouaz H.; Flotats, Albert; Jerome, Scott; Kaufmann, Philipp A.; Luxenburg, Osnat; Shaw, Leslee J.; Underwood, S. Richard; Rehani, Madan M.; Kashyap, Ravi; Paez, Diana; Dondi, Maurizio

    2015-01-01

    Aims To characterize patient radiation doses from nuclear myocardial perfusion imaging (MPI) and the use of radiation-optimizing ‘best practices’ worldwide, and to evaluate the relationship between laboratory use of best practices and patient radiation dose. Methods and results We conducted an observational cross-sectional study of protocols used for all 7911 MPI studies performed in 308 nuclear cardiology laboratories in 65 countries for a single week in March–April 2013. Eight ‘best practices’ relating to radiation exposure were identified a priori by an expert committee, and a radiation-related quality index (QI) devised indicating the number of best practices used by a laboratory. Patient radiation effective dose (ED) ranged between 0.8 and 35.6 mSv (median 10.0 mSv). Average laboratory ED ranged from 2.2 to 24.4 mSv (median 10.4 mSv); only 91 (30%) laboratories achieved the median ED ≤ 9 mSv recommended by guidelines. Laboratory QIs ranged from 2 to 8 (median 5). Both ED and QI differed significantly between laboratories, countries, and world regions. The lowest median ED (8.0 mSv), in Europe, coincided with high best-practice adherence (mean laboratory QI 6.2). The highest doses (median 12.1 mSv) and low QI (4.9) occurred in Latin America. In hierarchical regression modelling, patients undergoing MPI at laboratories following more ‘best practices’ had lower EDs. Conclusion Marked worldwide variation exists in radiation safety practices pertaining to MPI, with targeted EDs currently achieved in a minority of laboratories. The significant relationship between best-practice implementation and lower doses indicates numerous opportunities to reduce radiation exposure from MPI globally. PMID:25898845

  13. Medical radiation protection in next decade

    International Nuclear Information System (INIS)

    Rehani, M. M.; Vano, E.

    2011-01-01

    Interest in medical radiation protection today is the same as what it would have been almost a century ago. After many decades of relatively safe application of radiation in medicine, the recent spurt in over exposures, over-use of imaging and accidental exposures has created the need for stakeholders to join hands and contribute towards increasing radiation safety levels. Whether it be the need for technological developments to achieve sub-mSv CT scans, tracking of patient exposure history, accounting for repeated exposures of the same patient, specific consideration of requests for radiological examinations that deliver few mSv of dose, or utilization of regulatory approaches, radiological equipment will need to alert users whenever the radiation dose to the patient is above a defined value. The current decade will focus increasingly on carcinogenic effects in patients. (authors)

  14. Space Radiation Measurement on the Polar Route onboard the Korean Commercial Flights

    Directory of Open Access Journals (Sweden)

    Junga Hwang

    2010-03-01

    Full Text Available This study was performed by the policy research project of Ministry of Land, Transport and Maritime Affairs, which title is “Developing safety standards and management of space radiation on the polar route”. In this research, total six experiments were performed using Korean commercial flights (B747. Three of those are on the polar route and the other three are on the north pacific route. Space radiation exposure measured on the polar route is the average 84.7 uSv. The simulation result using CARI-6M program gives 84.9 uSv, which is very similar to measured value. For the departure flight using the north pacific route, the measured space radiation is the average 74.4 uSv. It seems that is not so different to use the polar route or not for the return flight because the higher latitude effect causing the increase of space radiation is compensated by the shortened flight time effect causing decreasing space radiation exposure.

  15. Long distance elementary measurement of the radiation dose ratio produced by neutron activation

    International Nuclear Information System (INIS)

    Zhou Changgeng; Lou Benchao; Wu Chunlei; Hu Yonghong; Li Yan

    2009-04-01

    The working principle and the structure and performances of a long distance controllable individual radiation dose ratio instrument are described. The radiation dose ratio produced by neutron activation is elementarily measured by using this instrument in the neutron generator hall with high neutron yield. When neutron yield arrives to 2 x 10 11 s -1 , the radiation dose ratio produced by neutron activation is 99.9 μSv/h in 1 h after the generator being stopped. The radiation dose ratio is reduced to 24.4 μSv/h in 39 h after the generator being stopped. When neutron yield is 3.2 x 10 10 s -1 , the radiation dose ratio produced by neutron activation is 21.9 μSv/h in 36 min, after the generator being stopped. The measurement results may provide reference for physical experimenters and neutron generator operators. (authors)

  16. Single- and dual-energy CT of the abdomen: comparison of radiation dose and image quality of 2nd and 3rd generation dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Wichmann, Julian L. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Hardie, Andrew D.; Felmly, Lloyd M.; Perry, Jonathan D.; Varga-Szemes, Akos; De Cecco, Carlo N. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Mangold, Stefanie [University Hospital of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Caruso, Damiano [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Radiological Sciences, Oncological and Pathological Sciences, Latina (Italy); Canstein, Christian [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Siemens Medical Solutions USA, Malvern, PA (United States); Vogl, Thomas J. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany)

    2017-02-15

    To compare single-energy (SECT) and dual-energy (DECT) abdominal CT examinations in matched patient cohorts regarding differences in radiation dose and image quality performed with second- and third-generation dual-source CT (DSCT). We retrospectively analysed 200 patients (100 male, 100 female; mean age 61.2 ± 13.5 years, mean body mass index 27.5 ± 3.8 kg/m{sup 2}) equally divided into four groups matched by gender and body mass index, who had undergone portal venous phase abdominal CT with second-generation (group A, 120-kV-SECT; group B, 80/140-kV-DECT) and third-generation DSCT (group C, 100-kV-SECT; group D, 90/150-kV-DECT). The radiation dose was normalised for 40-cm scan length. Dose-independent figure-of-merit (FOM) contrast-to-noise ratios (CNRs) were calculated for various organs and vessels. Subjective overall image quality and reader confidence were assessed. The effective normalised radiation dose was significantly lower (P < 0.001) in groups C (6.2 ± 2.0 mSv) and D (5.3 ± 1.9 mSv, P = 0.103) compared to groups A (8.8 ± 2.3 mSv) and B (9.7 ± 2.4 mSv, P = 0.102). Dose-independent FOM-CNR peaked for liver, kidney, and portal vein measurements (all P ≤ 0.0285) in group D. Subjective image quality and reader confidence were consistently rated as excellent in all groups (all ≥1.53 out of 5). With both DSCT generations, abdominal DECT can be routinely performed without radiation dose penalty compared to SECT, while third-generation DSCT shows improved dose efficiency. (orig.)

  17. The investigation of the Japanese black cattle as well as their rearing environment inside the 'difficult-to-return zone' due to Fukushima nuclear power plant disaster

    International Nuclear Information System (INIS)

    Okada, K.

    2016-01-01

    We are continuously investigating the effect of persistent exposure to low level radiation on Japanese Black cattle kept on 3 ranches as well as their rearing environment inside the 'difficult-to-return zone' due to Fukushima nuclear power plant disaster. The spatial radiation dose rate at 1 m above ground was 40 μSv/h in the spring of 2013 but it decreased to about 20 μSv/h after 1 year 7 months. Accumulated spatial radiation dose throughout the year of was 220 mSv and exposure dose of cattle throughout that year was 170 mSv. The effect of radiation exposure due to the nuclear power plant disaster has not been clearly recognized in cattle. (author)

  18. Transition in occupational radiation exposure monitoring methods in diagnostic and interventional radiology

    International Nuclear Information System (INIS)

    Loennroth, N.; Hirvonen-Kari, M.; Timonen, M.; Savolainen, S.; Kortesniemi, M.

    2008-01-01

    Radiation exposure monitoring is a traditional keystone of occupational radiation safety measures in medical imaging. The aim of this study was to review the data on occupational exposures in a large central university hospital radiology organisation and propose changes in the radiation worker categories and methods of exposure monitoring. An additional objective was to evaluate the development of electronic personal dosimeters and their potential in the digitised radiology environment. The personal equivalent dose of 267 radiation workers (116 radiologists and 151 radiographers) was monitored using personal dosimeters during the years 2006-2010. Accumulated exposure monitoring results exceeding the registration threshold were observed in the personal dosimeters of 73 workers (59 radiologists' doses ranged from 0.1 to 45.1 mSv; 14 radiographers' doses ranged from 0.1 to 1.3 mSv). The accumulated personal equivalent doses are generally very small, only a few angiography radiologists have doses >10 mSv per 5 y. The typical effective doses are -1 and the highest value was 0.3 mSv (single interventional radiologist). A revised categorisation of radiation workers based on the working profile of the radiologist and observed accumulated doses is justified. Occupational monitoring can be implemented mostly with group dosimeters. An active real-time dosimetry system is warranted to support radiation protection strategy where optimisation aspects, including improving working methods, are essential. (authors)

  19. The effective dose equivalent from external and internal radiation

    International Nuclear Information System (INIS)

    Mattsson, Soeren

    1989-01-01

    The various sources of low-level ionizing radiation are discussed and compared in terms of mean effective dose equivalent to man. For the most nonoccupationally exposed individuals, natural sources given the dominating contribution to the effective dose equivalent. The size of this contribution is strongly dependent on human activities. Natural sources contribution on average 2.4 mSV per year, of which half is due to irradiation of lungs and airways from short lived radon daughters present in indoor air. In Sweden this radon daughter contribution is considerably higher and contributes a mean of 3 mSv per year, thus giving a total contribution from natural radiation of about 4 mSV per year. In extreme cases, radon daughter contributions of several hundreds of mSv per year may be reached. Medical exposure, mainly diagnostic X-rays, contributes 0.4-1 mSv per year both in Sweden and as a world average. The testing of nuclear weapons in the atmosphere has given 1-2 mSv to each person in the world as a mean. The contribution from the routine operation of nuclear reactors is insignificant. The reactor accident in Chernobyl resulted in widely varying exposures of the European population. The average for Sweden is estimated to be 0.1 mSv during the first year and about 1 mSv during a 50-year period. For groups of Swedes who eat a considerable amount of game this contribution will be 10 times higher, and for the Lapps who breed reindeer in the most contaminated areas, typical values of 20-70 mSv and extreme values of about 1 Sv may be reached in 50 years. This means that the Chernobyl reactor accident for several years will be their dominating source of irradiation

  20. Assessment of terrestrial gamma radiation in Sudan

    International Nuclear Information System (INIS)

    Sam, A.K.; Ahamed, M.M.O.; El Khangi, F.A.; El Nigumi, Y.O.; Holm, E.

    1997-01-01

    Calculations of the external exposure due to γ radiation from the ground have been made from the results of the measurements of radionuclide activity concentrations in the soil at various locations in Sudan. The average exposure was found to be 45 nGy.h -1 , corresponding to the annual dose equivalent of 278 μSv.y -1 . With the exception of the Arkuri and Dumper areas in the western part of the country, the calculated exposure falls within the global wide range of outdoor radiation exposure given in the UNSCEAR publications. The nationwide average concentrations of 226 Ra, 238 U, 232 Th, 40 K and 137 Cs determined were 31.62, 20.11, 19.10, 280.29 and 4.12 Bq.kg -1 , respectively. This shows that there is little contamination due to fallout radioactivity at survey sites. (author)

  1. Assessment of environmental (226)Ra, (232)Th and (40)K concentrations in the region of elevated radiation background in Segamat District, Johor, Malaysia.

    Science.gov (United States)

    Saleh, Muneer Aziz; Ramli, Ahmad Termizi; Alajerami, Yasser; Aliyu, Abubakar Sadiq

    2013-10-01

    Extensive environmental survey and measurements of gamma radioactivity in the soil samples collected from Segamat District were conducted. Two gamma detectors were used for the measurements of background radiation in the area and the results were used in the computation of the mean external radiation dose rate and mean weighted dose rate, which are 276 nGy h(-1) and 1.169 mSv y(-1), respectively. A high purity germanium (HPGe) detector was used in the assessment of activity concentrations of (232)Th, (226)Ra and (40)K. The results of the gamma spectrometry range from 11 ± 1 to 1210 ± 41 Bq kg(-1) for (232)Th, 12 ± 1 to 968 ± 27 Bq kg(-1) for (226)Ra, and 12 ± 2 to 2450 ± 86 Bq kg(-1) for (40)K. Gross alpha and gross beta activity concentrations range from 170 ± 50 to 4360 ± 170 Bq kg(-1) and 70 ± 20 to 4690 ± 90 Bq kg(-1), respectively. These results were used in the plotting of digital maps (using ARCGIS 9.3) for isodose. The results are compared with values giving in UNSCEAR 2000. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Single-hit mechanism of tumour cell killing by radiation.

    Science.gov (United States)

    Chapman, J D

    2003-02-01

    To review the relative importance of the single-hit mechanism of radiation killing for tumour response to 1.8-2.0 Gy day(-1) fractions and to low dose-rate brachytherapy. Tumour cell killing by ionizing radiation is well described by the linear-quadratic equation that contains two independent components distinguished by dose kinetics. Analyses of tumour cell survival curves that contain six or more dose points usually provide good estimates of the alpha- and beta-inactivation coefficients. Superior estimates of tumour cell intrinsic radiosensitivity are obtained when synchronized populations are employed. The characteristics of single-hit inactivation of tumour cells are reviewed and compared with the characteristics of beta-inactivation. Potential molecular targets associated with single-hit inactivation are discussed along with strategies for potentiating cell killing by this mechanism. The single-hit mechanism of tumour cell killing shows no dependence on dose-rate and, consequently, no evidence of sublethal damage repair. It is uniquely potentiated by high linear-energy-transfer radiation, exhibits a smaller oxygen enhancement ratio and exhibits a larger indirect effect by hydroxyl radicals than the beta-mechanism. alpha-inactivation coefficients vary slightly throughout interphase but mitotic cells exhibit extremely high alpha-coefficients in the range of those observed for lymphocytes and some repair-deficient cells. Evidence is accumulating to suggest that chromatin in compacted form could be a radiation-hypersensitive target associated with single-hit radiation killing. Analyses of tumour cell survival curves demonstrate that it is the single-hit mechanism (alpha) that determines the majority of cell killing after doses of 2Gy and that this mechanism is highly variable between tumour cell lines. The characteristics of single-hit inactivation are qualitatively and quantitatively distinct from those of beta-inactivation. Compacted chromatin in tumour cells

  3. Radiation exposure assessment for Portsmouth Naval Shipyard health studies

    International Nuclear Information System (INIS)

    Daniels, R. D.; Taulbee, T. D.; Chen, P.

    2004-01-01

    Occupational radiation exposures of 13,475 civilian nuclear shipyard workers were investigated as part of a retrospective mortality study. Estimates of annual, cumulative and collective doses were tabulated for future dose-response analysis. Record sets were assembled and amended through range checks, examination of distributions and inspection. Methods were developed to adjust for administrative overestimates and dose from previous employment. Uncertainties from doses below the recording threshold were estimated. Low-dose protracted radiation exposures from submarine overhaul and repair predominated. Cumulative doses are best approximated by a hybrid log-normal distribution with arithmetic mean and median values of 20.59 and 3.24 mSv, respectively. The distribution is highly skewed with more than half the workers having cumulative doses 95% having doses <100 mSv. The maximum cumulative dose is estimated at 649.39 mSv from 15 person-years of exposure. The collective dose was 277.42 person-Sv with 96.8% attributed to employment at Portsmouth Naval Shipyard. (authors)

  4. SV2: accurate structural variation genotyping and de novo mutation detection from whole genomes.

    Science.gov (United States)

    Antaki, Danny; Brandler, William M; Sebat, Jonathan

    2018-05-15

    Structural variation (SV) detection from short-read whole genome sequencing is error prone, presenting significant challenges for population or family-based studies of disease. Here, we describe SV2, a machine-learning algorithm for genotyping deletions and duplications from paired-end sequencing data. SV2 can rapidly integrate variant calls from multiple structural variant discovery algorithms into a unified call set with high genotyping accuracy and capability to detect de novo mutations. SV2 is freely available on GitHub (https://github.com/dantaki/SV2). jsebat@ucsd.edu. Supplementary data are available at Bioinformatics online.

  5. Rat bone marrow progenitor cells transduced in situ by rSV40 vectors differentiate into multiple central nervous system cell lineages.

    Science.gov (United States)

    Louboutin, Jean-Pierre; Liu, Bianling; Reyes, Beverly A S; Van Bockstaele, Elisabeth J; Strayer, David S

    2006-12-01

    Using bone marrow-directed gene transfer, we tested whether bone marrow-derived cells may function as progenitors of central nervous system (CNS) cells in adult animals. SV40-derived gene delivery vectors were injected directly into femoral bone marrow, and we examined transgene expression in blood and brain for 0-16 months thereafter by immunostaining for FLAG epitope marker. An average of 5% of peripheral blood cells and 25% of femoral marrow cells were FLAG(+) throughout the study. CNS FLAG-expressing cells were mainly detected in the dentate gyrus (DG) and periventricular subependymal zone (PSZ). Although absent before 1 month and rare at 4 months, DG and PSZ FLAG(+) cells were abundant 16 months after bone marrow injection. Approximately 5% of DG cells expressed FLAG, including neurons (48.6%) and microglia (49.7%), and occasional astrocytes (1.6%), as determined by double immunostaining for FLAG and lineage markers. These data suggest that one or more populations of cells resident within adult bone marrow can migrate to the brain and differentiate into CNS-specific cells.

  6. Research of environmental radiation dose on the inside of residence next of uranium deposit in Espinharas, Paraiba, Brazil

    International Nuclear Information System (INIS)

    Dias Bezerra, Jairo; Dos Santos Amaral, Romilton; Araujo dos Santos Junior, Jose; Antonio da Silva, Alberto

    2015-01-01

    Humans are exposed to ionizing radiation, especially those natural sources originating from terrestrial radionuclides belonging to the radioactive series of 238 U and 233 Th, accompanied by the 40 K, which represents the major contribution to external and internal exposure. The increase of this dose in more than 40% in indoor environments is associated with building homes, close to areas with high levels of Natural Occurrences Radioactive Materials (NORM). The study area is located in the western region of the state of Paraiba and was chosen because it contains a major uranium deposits in Brazil, which has an average grade of 1,200 mg.kg -1 of U 3 O 8 . Were monitored 119 residences, in order to determine the effective doses in the air in indoor environments and the possible contribution of radon. For measure the doses, thermoluminescent dosimeters type LiF:Mg, Ti were used. The results obtained for effective dose rates, ranges from 0.71 to 2.07 mSv.y -1 , with an average value of 0.90 mSv.y -1 , getting these above the global reference value established by UNSCEAR that is 1.92 mSv.y -1 , should be investigated the condition of radioecological risk in indoor environments. (Author)

  7. Does iterative reconstruction lower CT radiation dose: evaluation of 15,000 examinations.

    Directory of Open Access Journals (Sweden)

    Peter B Noël

    Full Text Available PURPOSE: Evaluation of 15,000 computed tomography (CT examinations to investigate if iterative reconstruction (IR reduces sustainably radiation exposure. METHOD AND MATERIALS: Information from 15,000 CT examinations was collected, including all aspects of the exams such as scan parameter, patient information, and reconstruction instructions. The examinations were acquired between January 2010 and December 2012, while after 15 months a first generation IR algorithm was installed. To collect the necessary information from PACS, RIS, MPPS and structured reports a Dose Monitoring System was developed. To harvest all possible information an optical character recognition system was integrated, for example to collect information from the screenshot CT-dose report. The tool transfers all data to a database for further processing such as the calculation of effective dose and organ doses. To evaluate if IR provides a sustainable dose reduction, the effective dose values were statistically analyzed with respect to protocol type, diagnostic indication, and patient population. RESULTS: IR has the potential to reduce radiation dose significantly. Before clinical introduction of IR the average effective dose was 10.1±7.8mSv and with IR 8.9±7.1mSv (p*=0.01. Especially in CTA, with the possibility to use kV reduction protocols, such as in aortic CTAs (before IR: average14.2±7.8mSv; median11.4mSv /with IR:average9.9±7.4mSv; median7.4mSv, or pulmonary CTAs (before IR: average9.7±6.2mSV; median7.7mSv /with IR: average6.4±4.7mSv; median4.8mSv the dose reduction effect is significant(p*=0.01. On the contrary for unenhanced low-dose scans of the cranial (for example sinuses the reduction is not significant (before IR:average6.6±5.8mSv; median3.9mSv/with IR:average6.0±3.1mSV; median3.2mSv. CONCLUSION: The dose aspect remains a priority in CT research. Iterative reconstruction algorithms reduce sustainably and significantly radiation dose in the clinical routine

  8. Ionizing radiation measurements and assay of corresponding dose

    African Journals Online (AJOL)

    PUBLICATIONS1

    2014 Kwame Nkrumah University of Science and Technology (KNUST). Journal of Science and Technology, Vol. 34, No. 2 (2014) ... reasons related to the assessment or control of exposure to radiation or radioactive substances .... 15 mSv lens of eye; 50 mSv skin, hands, feet. Fig. 1: Geographical map of Nigeria showing ...

  9. Analysis of causes of radiation overexposures for radiation workers in industrial radiography

    International Nuclear Information System (INIS)

    Mahajan, J.M.; Massand, O.P.

    2001-01-01

    About 5500 radiation workers are monitored from industrial institutions in our country out of which 3600 radiation workers are working in industrial radiography institutions. These workers have a higher potential of receiving overexposure (equivalent dose 3 10 mSv) due to their nature of work. This paper presents analysis of overexposures and their causes for radiation workers working in industrial radiography institutions during the last seven years. (author)

  10. Optimization of radiation protection for the control of occupational exposures in Ghana

    International Nuclear Information System (INIS)

    Wortochi-Gordon, S.

    2009-06-01

    Investigation of the optimization of protection of occupational exposed workers (O.E.W.) in Ghana had been carried out across the three practices in the country namely medical applications, industrial radioisotope applications and research and education from 2002 to 2007. Annual effective doses and collective effective doses were estimated from dosimetry records from Radiation Protection Institute of those occupationally exposed from 2002 to 2007. The mean annual effective dose estimated for about 650 O.E.Ws per year ranged from 0.42±0.12mSv to 0.68±0.10mSv. The annual mean effective dose range is higher in comparison with the global values of 0.005mSv estimated by United Nations Scientific Committee on the effects of Atomic radiation (UNSCEAR 2008 Report). This implies that efforts should be made to institute ALARA culture in most practices in Ghana to be compatible with the global average. The collective effective dose for this same period estimated ranged from 0.26man.Sv to 0.47man.Sv. The annual mean collective effective dose range is much lower compared with other countries where large numbers of workers are occupationally exposed to ionizing radiation. A reference monetary value of the man-sievert was estimated using the human capital approach which provided a basis for estimating the cost of averting a unit collective effective dose of 1 man.Sv. This value could not be used for quantitative optimization since the mean annual doses for all the practices were below 1mSv (au).

  11. Radiation Exposure to Relatives of Patients Treated with Iodine-131 for Thyroid Cancer at Siriraj Hospital

    International Nuclear Information System (INIS)

    Tonnonchiang, S.; Sritongkul, N.; Chaudakshetrin, P.; Tuntawiroon, M.

    2012-01-01

    Thyroid carcinoma patients treated with I-131 are potential source of high radiation exposure to relatives who are knowingly and willingly exposed to ionizing radiation as a result of providing support and comfort to patients undergoing radionuclide therapy. The purpose of this study is to present the results of measurements of radiation doses to relatives who designated to care fornon self-supporting patients treated with radioiodine at Radionuclide Therapy Ward, Siriraj Hospital. Twenty caregivers of 20 patients underwent radioiodine therapy for thyroid cancers with a standard protocol were given specific instructions with regard to radiation safety and provided with electronic digital dosimeter (PDM 112) to continuously measure radiation dose received on the daily basis, during three days in the hospital. On the day of patients' release, in vivo bioassays were performed on caregivers to determine the thyroid uptake estimates. The 3-day accumulative doses to caregivers to patients receiving 5.55 GBq (n=11) and 7.4 GBq (n=9) of I-131 ranged from 37 to 333 μSv and 176 to 1920 μSv respectively depending on the extent and level of supports required. The thyroid uptake estimates in all caregivers were undetectable. Electronic dosimeters indicated a maximum whole-body effective dose of 1920 μSv was more than the public dose limit of 1 mSv but within the general dose constraint of 5 mSv. Radiation dose to caregivers of a non self-supporting hospitalized patient undergoing radioiodine therapy were well below the limits recommended by the ICRP and the IAEA. The patients can be comforted with confidence that dose to caregivers will be below the 5- mSv limit. This study provides guidance for medical practitioners to obtain practical radiation safety concerns associated with hospitalized patients receiving I-131 therapy especially when patients are comforted in the hospital ward by caregivers. (author)

  12. Radiation dose resulting from the releases of fly ash in the environment

    International Nuclear Information System (INIS)

    Koester, H.W.; Leenhouts, H.P.; Frissel, M.J.

    1986-06-01

    The radiological consequences from radioactivity in the emissions of coal fired power stations are evaluated for the Dutch population until the year 2030. The energy scenario for the Netherlands with the highest coal input considers an input of 55 Tg coal per year in 2030. The fly ash production is then 5.3 Tg, while 0.03 Tg fly ash will be released into the atmosphere. The radiation doses which result from the radionuclides present in the fly ash were calculated. Several pathways were considered, contribution of most of them were insignificant. However, the inhalation of fly ash may cause and H eff of 4.0 E-7 Sv.a -1 . The contribution caused by the ingestion of milk contaminated via depositions of fly ash on grass and soil may reach 0.8 E-7 Sv.a -1 . The report contains numerous calculations, references and a parameter analysis. (Auth.)

  13. Measures to reduce occupational radiation exposure in PET facilities from nurses' point of view

    International Nuclear Information System (INIS)

    Miyazawa, Keiko; Takahashi, Juri; Mochiduki, Yoshikazu

    2006-01-01

    In parallel with the increase in the number of institutions having PET facilities, the number of nurse working in these facilities has also increased, and the issue of occupational radiation exposure has assumed ever greater importance. In our clinic, since nurses have started to administer FDG intravenous injections, their annual radiation exposure has amounted to 4.8 - 7.1 mSv. To reduce their annual radiation exposure to less than 5 mSv, we identified sources of increased exposure and considered countermeasures based on this information. By implementing countermeasures such as improvements in daily working conditions and ways to avoid various troubles, it was possible to reduce the annual radiation exposure of all nurses to less than 5 mSv. Our experience demonstrates that to provide a working environment with a minimum of occupational radiation exposure, educational training and enhancement of knowledge and technical skills are vital. (author)

  14. The 1986 and 1988 UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) reports: Findings and implications

    International Nuclear Information System (INIS)

    Mettler, F.A.; Sinclair, W.K.; Anspaugh, L.; Edington, C.; Harley, J.H.; Ricks, R.C.; Selby, P.B.; Webster, E.W.; Wyckoff, H.O.

    1990-01-01

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has published a substantive series of reports concerning sources, effects, and risks of ionizing radiation. This article summarizes the highlights and conclusions from the most recent 1986 and 1988 reports. The present annual per person effective dose equivalent for the world's population is about 3 mSv. The majority of this (2.4 mSv) comes from natural background, and 0.4 to 1 mSv is from medical exposures. Other sources contribute less than 0.02 mSv annually. The worldwide collective effective dose equivalent annually is between 13 and 16 million person-Sv. The Committee assessed the collective effective dose equivalent to the population of the northern hemisphere from the reactor accident at Chernobyl and concluded that this is about 600,000 person-Sv. The Committee also reviewed risk estimates for radiation carcinogenesis which included the new Japanese dosimetry at Hiroshima and Nagasaki. These data indicate that risk coefficient estimates for high doses and high dose rate low-LET radiation in the Japanese population are approximately 3-10% Sv-1, depending on the projection model utilized. The Committee also indicated that, in calculation of such risks at low doses and low dose rates, a risk-reduction factor in the range of 2-10 may be considered

  15. Inactivation of E. Coli in Water Using Photocatalytic, Nanostructured Films Synthesized by Aerosol Routes

    Directory of Open Access Journals (Sweden)

    Pratim Biswas

    2013-03-01

    Full Text Available TiO2 nanostructured films were synthesized by an aerosol chemical vapor deposition (ACVD method with different controlled morphologies: columnar, granular, and branched structures for the photocatalytic inactivation of Escherichia coli (E. coli in water. Effects of film morphology and external applied voltage on inactivation rate were investigated. As-prepared films were characterized using scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffractometry (XRD, and UV-VIS. Photocatalytic and photoelectrochemical inactivation of E. coli using as-prepared TiO2 films were performed under irradiation of UVA light (note: UVA has a low efficiency to inactivate E. coli. Inactivation rate constants for each case were obtained from their respective inactivation curve through a 2 h incubation period. Photocatalytic inactivation rate constants of E. coli are 0.02/min (using columnar films, and 0.08/min (using branched films. The inactivation rate constant for the columnar film was enhanced by 330% by applied voltage on the film while that for the branched film was increased only by 30%. Photocatalytic microbial inactivation rate of the columnar and the branched films were also compared taking into account their different surface areas. Since the majority of the UV radiation that reaches the Earth’s surface is UVA, this study provides an opportunity to use sunlight to efficiently decontaminate drinking water.

  16. WE-AB-202-02: Incorporating Regional Ventilation Function in Predicting Radiation Fibrosis After Concurrent Chemoradiotherapy for Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lan, F; Jeudy, J; Tseng, H; Zhou, J; D’Souza, W; Zhang, H [University of Maryland, Baltimore, MD (United States); Senan, S; Sornsen de Koste, J van [VU University Medical Center, Amsterdam (Netherlands)

    2016-06-15

    Purpose: To investigate the incorporation of pre-therapy regional ventilation function in predicting radiation fibrosis (RF) in stage III non-small-cell lung cancer (NSCLC) patients treated with concurrent thoracic chemoradiotherapy. Methods: 37 stage III NSCLC patients were retrospectively studied. Patients received one cycle of cisplatin-gemcitabine, followed by two to three cycles of cisplatin-etoposide concurrently with involved-field thoracic radiotherapy between 46 and 66 Gy (2 Gy per fraction). Pre-therapy regional ventilation images of the lung were derived from 4DCT via a density-change-based image registration algorithm with mass correction. RF was evaluated at 6-months post-treatment using radiographic scoring based on airway dilation and volume loss. Three types of ipsilateral lung metrics were studied: (1) conventional dose-volume metrics (V20, V30, V40, and mean-lung-dose (MLD)), (2) dose-function metrics (fV20, fV30, fV40, and functional mean-lung-dose (fMLD) generated by combining regional ventilation and dose), and (3) dose-subvolume metrics (sV20, sV30, sV40, and subvolume mean-lung-dose (sMLD) defined as the dose-volume metrics computed on the sub-volume of the lung with at least 60% of the quantified maximum ventilation status). Receiver operating characteristic (ROC) curve analysis and logistic regression analysis were used to evaluate the predictability of these metrics for RF. Results: In predicting airway dilation, the area under the ROC curve (AUC) values for (V20, MLD), (fV20, fMLD), and (sV20, and sMLD) were (0.76, 0.70), (0.80, 0.74) and (0.82, 0.80), respectively. The logistic regression p-values were (0.09, 0.18), (0.02, 0.05) and (0.004, 0.006), respectively. With regard to volume loss, the corresponding AUC values for these metrics were (0.66, 0.57), (0.67, 0.61) and (0.71, 0.69), and p-values were (0.95, 0.90), (0.43, 0.64) and (0.08, 0.12), respectively. Conclusion: The inclusion of regional ventilation function improved

  17. Inactivation of catalase by free radicals derived from oxygen via gamma radiolysis

    International Nuclear Information System (INIS)

    Malhaire, J.P.; Gardes-Albert, M.; Ferradini, C.; Sabourault, D.; Ribiere, C.

    1991-01-01

    The inactivation of catalase (10 -5 mol/l) by OH· or OH·/O 2 - · free radicals, at pH 7.4, has been investigated using γ radiolysis with doses up to 9000 Gy. Maxima initial G-values of catalase inactivation have been determined. These values are inferior to those of the free radicals OH· and O 2 - · produced by water radiolysis. Nevertheless, the presence of O 2 /O 2 - · enhances the inactivation due to OH· radicals. The general shape of the inactivation curves as a function of the radiation dose is biphasic: an initial rapid phase (from 0 to ∼ 500 Gy) followed by a slow phase (from ∼ 500 to 9000 Gy). The addition of H 2 O 2 at the beginning of irradiation decreases the inactivation yield by OH· radicals. This phenomenon could be due to the formation of compound-I (catalase-H 2 O 2 ) which would be less sensitive towards OH· radicals than catalase. In the presence of 0.1 mol/l ethanol, catalase (5 x 10 -6 mol/l) is not inactived by O 2 - · and RO 2 · (from ethanol) radicals for an irradiation dose of 2000 Gy, implying a complete protecting effect by ethanol [fr

  18. Analysis of overexposure cases for female radiation workers in medical and research institutions in India

    International Nuclear Information System (INIS)

    Mahajan, J.M.; Massand, O.P.; Venkataraman, G.

    1996-01-01

    Radiation Protection Services Division, Bhabha Atomic Research Centre conducts country wide personnel monitoring service for 40,000 radiation workers, of which about 22,000 radiation workers are from industrial, medical and research institutions. The number of female radiation workers constitute about 5% of the total radiation workers monitored. Basis for control of occupational exposures of women are same as that for men except for pregnant women (foetus). Equivalent dose above 10 mSv in a service period is investigated as to the causes of exposure whether the exposure was really received by the worker (genuine) or only the monitoring badge received the exposure due to other reasons (non-genuine) and necessary remedial actions are taken. Analysis of overexposure cases in female radiation workers as a group has been done for the period of four years (1990-1993) and the conclusions are presented. (author). 2 refs., 4 tabs

  19. BOOK REVIEW: NCRP Report No. 160: Ionizing Radiation Exposure of the