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Sample records for murine radiation-induced acute

  1. Mapping of murine radiation-induced acute myeloid leukaemia susceptibility loci

    International Nuclear Information System (INIS)

    Darakhshan, F.

    2001-01-01

    Studies on radiation-induced AML have shown characteristic phenotypic variation in susceptibility amongst inbred mouse strains, suggesting the involvement of genetic factors in determining the development of AML post-irradiation exposure. The main objective of the present study therefore was to identify and map markers in linkage disequilibrium with gene variants associated with influencing susceptibility to radiation induced AML in mice. Given Chr 2 abnormalities are characteristic of AML in mice, this feature was exploited in an effort to overcome the long latency for AML development. Analysis of Chr 2 aberrations at 24 and 48 h following irradiation established a positive correlation between Chr 2 radiosensitivity and radiation-AML susceptibility thus validating the choice of substitute assay. The analysis also resulted in the identification of a further trait, additional to Chr 2 radiosensitivity, termed overall chromosome radiosensitivity. Genetic mapping of Chr 2 radiosensitivity using public domain microsatellite database information resulted in the definition of cluster regions on 7 different chromosomes. Further genotyping reduced the candidate regions to 3 specific regions of interest. A test of allelic association could not ascertain a conclusive link between markers at these regions and the Chr 2 radiosensitivity/radiation-AML susceptibility phenotype. However, a region on Chr 4 around D4Mit221 appears to be most strongly associated. Similar studies identified three chromosomal regions of interest (on Chrs 4, 8 and 16) associated with overall chromosome radiosensitivity trait. An independent mapping strategy using F3 RCS confirmed the likely involvement of two of the candidate Chr 2 radiosensitivity regions identified by the inbred analysis including that on Chr 4 and also highlighted phenotypic heterogeneity amongst resistant RC strains, suggesting the influence of multiple alleles in specific phenotypes. RFLP analysis of candidate genes, localised on

  2. microRNA Alterations Driving Acute and Late Stages of Radiation-Induced Fibrosis in a Murine Skin Model

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    Simone, Brittany A. [Department of Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College of Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Ly, David; Savage, Jason E. [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Hewitt, Stephen M. [Department of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Dan, Tu D. [Department of Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College of Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Ylaya, Kris [Department of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Shankavaram, Uma [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Lim, Meng; Jin, Lianjin [Department of Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College of Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Camphausen, Kevin [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Mitchell, James B. [Radiation Biology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Simone, Nicole L., E-mail: nicole.simone@jeffersonhospital.org [Department of Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College of Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States)

    2014-09-01

    Purpose: Although ionizing radiation is critical in treating cancer, radiation-induced fibrosis (RIF) can have a devastating impact on patients' quality of life. The molecular changes leading to radiation-induced fibrosis must be elucidated so that novel treatments can be designed. Methods and Materials: To determine whether microRNAs (miRs) could be responsible for RIF, the fibrotic process was induced in the right hind legs of 9-week old CH3 mice by a single-fraction dose of irradiation to 35 Gy, and the left leg served as an unirradiated control. Fibrosis was quantified by measurements of leg length compared with control leg length. By 120 days after irradiation, the irradiated legs were 20% (P=.013) shorter on average than were the control legs. Results: Tissue analysis was done on muscle, skin, and subcutaneous tissue from irradiated and control legs. Fibrosis was noted on both gross and histologic examination by use of a pentachrome stain. Microarrays were performed at various times after irradiation, including 7 days, 14 days, 50 days, 90 days, and 120 days after irradiation. miR-15a, miR-21, miR-30a, and miR-34a were the miRs with the most significant alteration by array with miR-34a, proving most significant on confirmation by reverse transcriptase polymerase chain reaction, c-Met, a known effector of fibrosis and downstream molecule of miR-34a, was evaluated by use of 2 cell lines: HCT116 and 1522. The cell lines were exposed to various stressors to induce miR changes, specifically ionizing radiation. Additionally, in vitro transfections with pre-miRs and anti-miRs confirmed the relationship of miR-34a and c-Met. Conclusions: Our data demonstrate an inverse relationship with miR-34a and c-Met; the upregulation of miR-34a in RIF causes inhibition of c-Met production. miRs may play a role in RIF; in particular, miR-34a should be investigated as a potential target to prevent or treat this devastating side effect of irradiation.

  3. Genomic rearrangement in radiation-induced murine myeloid leukemia

    International Nuclear Information System (INIS)

    Ishihara, Hiroshi

    1994-01-01

    After whole body irradiation of 3Gy X ray to C3H/He male mice, acute myeloid leukemia is induced at an incidence of 20 to 30% within 2 years. We have studied the mechanism of occurrence of this radiation-induced murine myeloid leukemia. Detection and isolation of genomic structural aberration which may be accumulated accompanied with leukemogenesis are helpful in analyzing the complicated molecular process from radiation damage to leukemogenesis. So, our research work was done in three phases. First, structures of previously characterized oncogenes and cytokine-related genes were analyzed, and abnormal structures of fms(protooncogene encoding M-CSF receptor gene)-related and myc-related genes were found in several leukemia cells. Additionally, genomic structural aberration of IL-3 gene was observed in some leukemia cells, so that construction of genomic libraries and cloning of the abnormal IL-3 genomic DNAs were performed to characterize the structure. Secondly, because the breakage of chromosome 2 that is frequently observed in myeloid leukemia locates in proximal position of IL-1 gene cluster in some cases, the copy number of IL-1 gene was determined and the gene was cloned. Lastly, the abnormal genome of leukemia cell was cloned by in-gel competence reassociation method. We discussed these findings and evaluated the analysis of the molecular process of leukemogenesis using these cloned genomic fragments. (author)

  4. Role of sphingolipids in murine radiation-induced lung injury: protection by sphingosine 1-phosphate analogs

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    Mathew, Biji; Jacobson, Jeffrey R.; Berdyshev, Evgeny; Huang, Yong; Sun, Xiaoguang; Zhao, Yutong; Gerhold, Lynnette M.; Siegler, Jessica; Evenoski, Carrie; Wang, Ting; Zhou, Tong; Zaidi, Rafe; Moreno-Vinasco, Liliana; Bittman, Robert; Chen, Chin Tu

    2011-01-01

    Clinically significant radiation-induced lung injury (RILI) is a common toxicity in patients administered thoracic radiotherapy. Although the molecular etiology is poorly understood, we previously characterized a murine model of RILI in which alterations in lung barrier integrity surfaced as a potentially important pathobiological event and genome-wide lung gene mRNA levels identified dysregulation of sphingolipid metabolic pathway genes. We hypothesized that sphingolipid signaling components...

  5. Role of sphingolipids in murine radiation-induced lung injury: protection by sphingosine 1-phosphate analogs

    Science.gov (United States)

    Mathew, Biji; Jacobson, Jeffrey R.; Berdyshev, Evgeny; Huang, Yong; Sun, Xiaoguang; Zhao, Yutong; Gerhold, Lynnette M.; Siegler, Jessica; Evenoski, Carrie; Wang, Ting; Zhou, Tong; Zaidi, Rafe; Moreno-Vinasco, Liliana; Bittman, Robert; Chen, Chin Tu; LaRiviere, Patrick J.; Sammani, Saad; Lussier, Yves A.; Dudek, Steven M.; Natarajan, Viswanathan; Weichselbaum, Ralph R.; Garcia, Joe G. N.

    2011-01-01

    Clinically significant radiation-induced lung injury (RILI) is a common toxicity in patients administered thoracic radiotherapy. Although the molecular etiology is poorly understood, we previously characterized a murine model of RILI in which alterations in lung barrier integrity surfaced as a potentially important pathobiological event and genome-wide lung gene mRNA levels identified dysregulation of sphingolipid metabolic pathway genes. We hypothesized that sphingolipid signaling components serve as modulators and novel therapeutic targets of RILI. Sphingolipid involvement in murine RILI was confirmed by radiation-induced increases in lung expression of sphingosine kinase (SphK) isoforms 1 and 2 and increases in the ratio of ceramide to sphingosine 1-phosphate (S1P) and dihydro-S1P (DHS1P) levels in plasma, bronchoalveolar lavage fluid, and lung tissue. Mice with a targeted deletion of SphK1 (SphK1−/−) or with reduced expression of S1P receptors (S1PR1+/−, S1PR2−/−, and S1PR3−/−) exhibited marked RILI susceptibility. Finally, studies of 3 potent vascular barrier-protective S1P analogs, FTY720, (S)-FTY720-phosphonate (fTyS), and SEW-2871, identified significant RILI attenuation and radiation-induced gene dysregulation by the phosphonate analog, fTyS (0.1 and 1 mg/kg i.p., 2×/wk) and to a lesser degree by SEW-2871 (1 mg/kg i.p., 2×/wk), compared with those in controls. These results support the targeting of S1P signaling as a novel therapeutic strategy in RILI.—Mathew, B., Jacobson, J. R., Berdyshev, E., Huang, Y., Sun, X., Zhao, Y., Gerhold, L. M., Siegler, J., Evenoski, C., Wang, T., Zhou, T., Zaidi, R., Moreno-Vinasco, L., Bittman, R., Chen, C. T., LaRiviere, P. J., Sammani, S., Lussier, Y. A., Dudek, S. M., Natarajan, V., Weichselbaum, R. R., Garcia, J. G. N. Role of sphingolipids in murine radiation-induced lung injury: protection by sphingosine 1-phosphate analogs. PMID:21712494

  6. Loss of Matrix Metalloproteinase-13 Attenuates Murine Radiation-Induced Pulmonary Fibrosis

    International Nuclear Information System (INIS)

    Flechsig, Paul; Hartenstein, Bettina; Teurich, Sybille; Dadrich, Monika; Hauser, Kai; Abdollahi, Amir; Groene, Hermann-Josef; Angel, Peter; Huber, Peter E.

    2010-01-01

    Purpose: Pulmonary fibrosis is a disorder of the lungs with limited treatment options. Matrix metalloproteinases (MMPs) constitute a family of proteases that degrade extracellular matrix with roles in fibrosis. Here we studied the role of MMP13 in a radiation-induced lung fibrosis model using a MMP13 knockout mouse. Methods and Materials: We investigated the role of MMP13 in lung fibrosis by investigating the effects of MMP13 deficiency in C57Bl/6 mice after 20-Gy thoracic irradiation (6-MV Linac). The morphologic results in histology were correlated with qualitative and quantitative results of volume computed tomography (VCT), magnetic resonance imaging (MRI), and clinical outcome. Results: We found that MMP13 deficient mice developed less pulmonary fibrosis than their wildtype counterparts, showed attenuated acute pulmonary inflammation (days after irradiation), and a reduction of inflammation during the later fibrogenic phase (5-6 months after irradiation). The reduced fibrosis in MMP13 deficient mice was evident in histology with reduced thickening of alveolar septi and reduced remodeling of the lung architecture in good correlation with reduced features of lung fibrosis in qualitative and quantitative VCT and MRI studies. The partial resistance of MMP13-deficient mice to fibrosis was associated with a tendency towards a prolonged mouse survival. Conclusions: Our data indicate that MMP13 has a role in the development of radiation-induced pulmonary fibrosis. Further, our findings suggest that MMP13 constitutes a potential drug target to attenuate radiation-induced lung fibrosis.

  7. Modulation of radiation-induced apoptosis and G{sub 2}/M block in murine T-lymphoma cells

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    Palayoor, S.T.; Macklis, R.M.; Bump, E.A.; Coleman, C.N. [Harvard Medical School, Boston, MA (United States)

    1995-03-01

    Radiation-induced apoptosis in lymphocyte-derived cell lines is characterized by endonucleolytic cleavage of cellular DNA within hours after radiation exposure. We have studied this phenomenon qualitatively (DNA gel electrophoresis) and quantitatively (diphenylamine reagent assay) in murine EL4 T-lymphoma cells exposed to {sup 137}Cs {gamma} irradiation. Fragmentation was discernible within 18-24 h after exposure. It increased with time and dose and reached a plateau after 8 Gy of {gamma} radiation. We studied the effect of several pharmacological agents on the radiation-induced G{sub 2}/M block and DNA fragmentation. The agents which reduced the radiation-induced G{sub 2}/M-phase arrest (caffeine, theobromine, theophylline and 2-aminopurine) enhanced the degree of DNA fragmentation at 24 h. In contrast, the agents which sustained the radiation-induced G{sub 2}/M-phase arrest (TPA, DBcAMP, IBMX and 3-aminobenzamide) inhibited the DNA fragmentation at 24 h. These studies on EL4 lymphoma cells are consistent with the hypothesis that cells with radiation-induced genetic damage are eliminated by apoptosis subsequent to a G{sub 2}/M block. Furthermore, it may be possible to modulate the process of radiation-induced apoptosis in lymphoma cells with pharmacological agents that modify the radiation-induced G{sub 2}/M block, and to use this effect in the treatment of patients with malignant disease. 59 refs., 7 figs.

  8. Modulation of radiation-induced apoptosis and G2/M block in murine T-lymphoma cells

    International Nuclear Information System (INIS)

    Palayoor, S.T.; Macklis, R.M.; Bump, E.A.; Coleman, C.N.

    1995-01-01

    Radiation-induced apoptosis in lymphocyte-derived cell lines is characterized by endonucleolytic cleavage of cellular DNA within hours after radiation exposure. We have studied this phenomenon qualitatively (DNA gel electrophoresis) and quantitatively (diphenylamine reagent assay) in murine EL4 T-lymphoma cells exposed to 137 Cs γ irradiation. Fragmentation was discernible within 18-24 h after exposure. It increased with time and dose and reached a plateau after 8 Gy of γ radiation. We studied the effect of several pharmacological agents on the radiation-induced G 2 /M block and DNA fragmentation. The agents which reduced the radiation-induced G 2 /M-phase arrest (caffeine, theobromine, theophylline and 2-aminopurine) enhanced the degree of DNA fragmentation at 24 h. In contrast, the agents which sustained the radiation-induced G 2 /M-phase arrest (TPA, DBcAMP, IBMX and 3-aminobenzamide) inhibited the DNA fragmentation at 24 h. These studies on EL4 lymphoma cells are consistent with the hypothesis that cells with radiation-induced genetic damage are eliminated by apoptosis subsequent to a G 2 /M block. Furthermore, it may be possible to modulate the process of radiation-induced apoptosis in lymphoma cells with pharmacological agents that modify the radiation-induced G 2 /M block, and to use this effect in the treatment of patients with malignant disease. 59 refs., 7 figs

  9. DNA copy number analysis from mice with radiation-induced acute myeloid leukemia

    Data.gov (United States)

    National Aeronautics and Space Administration — Certain mouse strains such as CBA C3H and RFM have high incidence of radiation-induced acute myeloid leukemia (AML). The data in this series wer generated by using...

  10. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    Science.gov (United States)

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  11. Radiation Induced Apoptosis of Murine Bone Marrow Cells Is Independent of Early Growth Response 1 (EGR1.

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    Karine Z Oben

    Full Text Available An understanding of how each individual 5q chromosome critical deleted region (CDR gene contributes to malignant transformation would foster the development of much needed targeted therapies for the treatment of therapy related myeloid neoplasms (t-MNs. Early Growth Response 1 (EGR1 is a key transcriptional regulator of myeloid differentiation located within the 5q chromosome CDR that has been shown to regulate HSC (hematopoietic stem cell quiescence as well as the master regulator of apoptosis-p53. Since resistance to apoptosis is a hallmark of malignant transformation, we investigated the role of EGR1 in apoptosis of bone marrow cells; a cell population from which myeloid malignancies arise. We evaluated radiation induced apoptosis of Egr1+/+ and Egr1-/- bone marrow cells in vitro and in vivo. EGR1 is not required for radiation induced apoptosis of murine bone marrow cells. Neither p53 mRNA (messenger RNA nor protein expression is regulated by EGR1 in these cells. Radiation induced apoptosis of bone marrow cells by double strand DNA breaks induced p53 activation. These results suggest EGR1 dependent signaling mechanisms do not contribute to aberrant apoptosis of malignant cells in myeloid malignancies.

  12. Investigations of antioxidant-mediated protection and mitigation of radiation-induced DNA damage and lipid peroxidation in murine skin.

    Science.gov (United States)

    Jelveh, Salomeh; Kaspler, Pavel; Bhogal, Nirmal; Mahmood, Javed; Lindsay, Patricia E; Okunieff, Paul; Doctrow, Susan R; Bristow, Robert G; Hill, Richard P

    2013-08-01

    Radioprotection and mitigation effects of the antioxidants, Eukarion (EUK)-207, curcumin, and the curcumin analogs D12 and D68, on radiation-induced DNA damage or lipid peroxidation in murine skin were investigated. These antioxidants were studied because they have been previously reported to protect or mitigate against radiation-induced skin reactions. DNA damage was assessed using two different assays. A cytokinesis-blocked micronucleus (MN) assay was performed on primary skin fibroblasts harvested from the skin of C3H/HeJ male mice 1 day, 1 week and 4 weeks after 5 Gy or 10 Gy irradiation. Local skin or whole body irradiation (100 kVp X-rays or caesium (Cs)-137 γ-rays respectively) was performed. DNA damage was further quantified in keratinocytes by immunofluorescence staining of γ-histone 2AX (γ-H2AX) foci in formalin-fixed skin harvested 1 hour or 1 day post-whole body irradiation. Radiation-induced lipid peroxidation in the skin was investigated at the same time points as the MN assay by measuring malondialdehyde (MDA) with a Thiobarbituric acid reactive substances (TBARS) assay. None of the studied antioxidants showed significant mitigation of skin DNA damage induced by local irradiation. However, when EUK-207 or curcumin were delivered before irradiation they provided some protection against DNA damage. In contrast, all the studied antioxidants demonstrated significant mitigating and protecting effects on radiation-induced lipid peroxidation at one or more of the three time points after local skin irradiation. Our results show no evidence for mitigation of DNA damage by the antioxidants studied in contrast to mitigation of lipid peroxidation. Since these agents have been reported to mitigate skin reactions following irradiation, the data suggest that changes in lipid peroxidation levels in skin may reflect developing skin reactions better than residual post-irradiation DNA damage in skin cells. Further direct comparison studies are required to confirm

  13. Modification of radiation-induced murine thymic lymphoma incidence by curcumin

    International Nuclear Information System (INIS)

    Dange, P.S.; Yadav, H.D.; Kumar, Vimalesh; Bhilwade, H.N.; Pandey, B.N.; Sarma, H.D.

    2017-01-01

    Curcumin is a known antioxidant, preventing radiation damage including carcinogenesis. However, concentration and feeding schedule of curcumin in modification of radiation induced thymic lymphoma incidence in vivo model has not been studied. We report here modification of incidence of γ-radiation-induced thymic lymphoma in mice fed with different doses of curcumin (0.05 to 1 %) in diet. Results: Female Swiss mice (6-8 weeks) fed with normal diet and exposed to 3 Gy whole body "6"0Co γ-irradiation (WBI) showed 85 % incidence of thymic lymphoma (TL) at 120 days post-irradiation. A concentration of 1 % curcumin was found the most effective in TL incidence prevention than other fed concentrations. The TL incidence was remarkably reduced when curcumin was fed to the mice before than after the radiation exposure. These results suggest modification of TL incidence by curcumin in irradiated mice involving DNA damage and apoptotic death mechanisms

  14. Radiation-induced acute myeloid leukaemia in mice

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    Bouffler, S.D.; Silver, A.R.J.; Cox, R. [National Radiological Protection Board, Chilton (United Kingdom)

    2000-07-01

    Ample epidemiological studies of human populations implicate ionizing radiation as a carcinogen and these quantitative studies provide the foundation for the core estimates of radiation cancer risk. The majority of the epidemiological data originate from situations of radiation exposure at high dose and high dose rate. The relevance of risk estimates based on such exposures to the more commonly encountered low dose and dose rate situation has been questioned frequently. Thus, there is a need to investigate and quantitate low dose and dose rate effects. A number of approaches may be considered, for example, very large scale epidemiology, very large scale animal experimentation; however, both of these present problems of a practical and/or ethical nature. A further possible approach is that of mechanistic modelling. This requires a fairly detailed understanding of neoplastic disease and how it develops post-irradiation. Many factors and variables have to be taken into consideration in mechanistic modelling approaches. Testing of mechanistic modelling schemes is best carried out using animal model systems. Acute myeloid leukaemia (AML) is a radiogenic cancer of significance in man and several good mouse models of the disease are available. Here, recent studies conducted at NRPB with the aim of elucidating the post-irradiation development of AML will be discussed. In particular three areas critical for developing a sound mechanistic model will be covered, definition of the initiating event; study of disease progression, this addresses the question of the frequency of conversion of initiated cells into the neoplastic state and the influence of genetic background on leukaemogenesis. (author)

  15. Lack of spontaneous and radiation-induced chromosome breakage at interstitial telomeric sites in murine scid cells.

    Science.gov (United States)

    Wong, H-P; Mozdarani, H; Finnegan, C; McIlrath, J; Bryant, P E; Slijepcevic, P

    2004-01-01

    Interstitial telomeric sites (ITSs) in chromosomes from DNA repair-proficient mammalian cells are sensitive to both spontaneous and radiation-induced chromosome breakage. Exact mechanisms of this chromosome breakage sensitivity are not known. To investigate factors that predispose ITSs to chromosome breakage we used murine scid cells. These cells lack functional DNA-PKcs, an enzyme involved in the repair of DNA double-strand breaks. Interestingly, our results revealed lack of both spontaneous and radiation-induced chromosome breakage at ITSs found in scid chromosomes. Therefore, it is possible that increased sensitivity of ITSs to chromosome breakage is associated with the functional DNA double-strand break repair machinery. To investigate if this is the case we used scid cells in which DNA-PKcs deficiency was corrected. Our results revealed complete disappearance of ITSs in scid cells with functional DNA-PKcs, presumably through chromosome breakage at ITSs, but their unchanged frequency in positive and negative control cells. Therefore, our results indicate that the functional DNA double-strand break machinery is required for elevated sensitivity of ITSs to chromosome breakage. Interestingly, we observed significant differences in mitotic chromosome condensation between scid cells and their counterparts with restored DNA-PKcs activity suggesting that lack of functional DNA-PKcs may cause a defect in chromatin organization. Increased condensation of mitotic chromosomes in the scid background was also confirmed in vivo. Therefore, our results indicate a previously unanticipated role of DNA-PKcs in chromatin organisation, which could contribute to the lack of ITS sensitivity to chromosome breakage in murine scid cells. Copyright 2003 S. Karger AG, Basel

  16. Therapy and prophylaxis of acute and late radiation-induced sequelae of the esophagus

    International Nuclear Information System (INIS)

    Zimmermann, F.B.; Geinitz, H.; Feldmann, H.J.

    1998-01-01

    Background: Radiation-induced esophagitis is a frequent acute side effect in curative and palliative radiotherapy of thoracal and cervical tumors. Late reactions are rare but might be severe. Methods: A resarch for reports on prophylactic and supportive therapies of radiation-induced esophagitis was performed (Medline, Cancerlit, and others). Results: Nutrition must be ensured and symptomatic relief of sequelae is important, especially in the case of dysphagia. The latter can be improved by topic or systemic analgetics. If esophageal spasm occurs, calcium antagonists might help. In case of gastro-esophageal reflux proton pump inhibitors should be used. There is no effective prophylactic measure for radiation esophagitis. Late side effects with clinical relevance are rare in conventional radiotherapy. Chronic ulcera, fistula or stenosis may develop. Before any treatment, a tumor infiltration of the esophagus should be excluded by biopsy. This can lead more often to late complications than radiation therapy itself. Nutrition should be ensured by endoscopic dilation, stent-implantation, or endoscopic percutaneous gastrostomy. Local injection of steroids might be used to avoid an early restenosis. Conclusions: An intensive symptomatic therapy of acute esophagitis is reasonable. Effective prophylaxis do not exist. Late radiation induced sequelae is rare. Therefore, a tumor recurrence should be excluded in cases of dysphagia. Securing nutrition by PEG, stent, or port is well in the fore. (orig.) [de

  17. High-dose radiation-induced meningioma following prophylactic cranial irradiation for acute lymphoblastic leukaemia

    International Nuclear Information System (INIS)

    Matsuda, Ryosuke; Nikaido, Yuji; Yamada, Tomonori; Mishima, Hideaki; Tamaki, Ryo

    2005-01-01

    A 12 year-old girl was treated with prophylactic cranial irradiation for acute lymphoblastic leukaemia (ALL). At the age of 39, she was admitted to our hospital for status epilepticus. Computed tomography demonstrated two, enhancing bilateral sided intracranial tumors. After surgery, this patient presented meningiomas which histologically, were of the meningothelial type. The high cure rate in childhood ALL, attributable to aggressive chemotherapy and prophylactic cranial irradiation, is capable of inducing secondary brain tumor. Twelve cases of high-dose radiation-induced meningioma following ALL are also reviewed. (author)

  18. High-dose radiation-induced meningioma following prophylactic cranial irradiation for acute lymphoblastic leukaemia

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    Matsuda, Ryosuke; Nikaido, Yuji; Yamada, Tomonori; Mishima, Hideaki; Tamaki, Ryo [National Hospital Organization Osaka Minami Medical Center, Kawachinagano (Japan)

    2005-03-01

    A 12 year-old girl was treated with prophylactic cranial irradiation for acute lymphoblastic leukaemia (ALL). At the age of 39, she was admitted to our hospital for status epilepticus. Computed tomography demonstrated two, enhancing bilateral sided intracranial tumors. After surgery, this patient presented meningiomas which histologically, were of the meningothelial type. The high cure rate in childhood ALL, attributable to aggressive chemotherapy and prophylactic cranial irradiation, is capable of inducing secondary brain tumor. Twelve cases of high-dose radiation-induced meningioma following ALL are also reviewed. (author)

  19. Scintigraphic and Endoscopic Evaluation of Radiation-induced Acute Gastrointestinal Syndrome in Micro-pig Model

    International Nuclear Information System (INIS)

    Lee, Seung-Sook; Kim, Kyung-Min; Kim, Jin; Jang, Won-Suk; Lee, Jung-Eun; Kim, Noo-Ri; Lee, Sun-Joo; Kim, Mi-Sook; Ji, Young-Hoon; Cheon, Gi-Jeong; Lim, Sang-Moo

    2007-01-01

    Micro-pig model can be served as a proper substitute for humans in studying acute radiation syndrome following radiation-exposure accidents, especially showing similar clinico-pathologic response of hematopoietic and gastrointestinal (GI) syndrome to human. Among acute GI syndrome induced by radiation, GI motility disturbance has not been studied, however, it would be important in a viewpoint of affecting infectious progression from GI tract. Here, we employed scintigraphy of GI transit time and sequential endoscopic examination and tissue sampling in micropigs followed by abdominal radiation exposure. The specific aims of this study are to evaluate objective evidence of GI motility disturbance by scintigraphic evaluation and to find corresponding clinicoapthologic changes in radiation-induced acute GI syndrome

  20. Expression of intracisternal A-particles in radiation-induced murine osteosarcomas

    International Nuclear Information System (INIS)

    Seidel, E.

    1989-01-01

    The expression of intracisternal A-type particles (IAPs) and the distribution of the corresponding type I and type II genes was investigated in radiation induced osteosarcomas of Balb/c, NMRI and CBA mice. The results can be summarized as follows: 1. Slot blot analysis showed that 9 out of 23 (i.e. 39%) of the examined tumours had enhanced IAP expression as compared to normal tissues. None of the CBA tumours were enhanced in IAP expression - only tumours of the strains Balb/c and NMRI expressed higher levels of IAP RNA. 2. Northern blot analysis of RNA from osteosarcomas revealed that the two IAP transcrips (7.2 kb and 5.4 kb) had the same mobility in these tissues as in normal tissue. Some tumours showed a higher level of expression of the 7.2 kb transcript as compared to normal tissues. This 7.2 kb transcript encodes the major structural protein p 73 of IAPs. 3. Hybridization of Southern blots of mouse DNA using the IAP type I specific probe revealed a unique fragment in three of the investigated Balb/c osteosarcomas. 4. Although it could not directly be shown that IAPs were involved in the genesis of osteosarcomas, the changes in IAP expression and the unique fragments suggest a possible correlation with tumour progression. In this light the level of IAP expression may serve as a marker for the degree of the malignancy of the tumour. (orig.) [de

  1. Radiation-induced alterations in murine lymphocyte homing patterns. I. Radiolabeling studies

    International Nuclear Information System (INIS)

    Crouse, D.A.; Feldbush, T.L.; Evans, T.C.

    1976-01-01

    In vitro x-irradiation of 51 Cr-labeled spleen, lymph node, bone marrow, or thymus cells was found to alter their subsequent in vivo distribution significantly in syngeneic BDF 1 mice. Irradiated cells demonstrated an increased distribution to the liver and a significantly lower retention in the lungs. Cells going to the lymph nodes or Peyer's patches showed a significant exposure-dependent decrease in homing following irradiation. Irradiated lymph node cells homed in greater numbers to the spleen and bone marrow, while irradiated cells from other sources showed no preferential distribution to the same tissues. Sampling host tissues at various times after irradiation and injection did not demonstrate any return to normal patterns of distribution. The alterations in lymphocyte homing observed after in vitro irradiation appear to be due to the elimination of a selective population of lymphocytes or membrane alterations of viable cells, and the detection of these homing changes is in turn dependent upon the relative numbers of various lymphoid subpopulations which are obtained from different cell sources. Radiation-induced alterations in the normal homing patterns of lymphoid cells may thus be of considerable importance in the evaluation of subsequent functional assays in recipient animals

  2. Murine liver implantation of radiation-induced fibrosarcoma: characterization with MR imaging, microangiography and histopathology

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    Wang, Huaijun; Keyzer, Frederik de; Jin, Lixin; Yu, Jie; Marchal, Guy; Ni, Yicheng [Catholic University of Leuven, Department of Radiology, University Hospitals, Leuven (Belgium); Putte, Marie van de; Witte, Peter de [K.U. Leuven, Laboratory for Pharmaceutical Biology, Faculty of Pharmaceutical Sciences, Leuven (Belgium); Chen, Feng [Catholic University of Leuven, Department of Radiology, University Hospitals, Leuven (Belgium); Southeast University, Department of Radiology, Zhong Da Hospital, Nanjing, Jiangsu Province (China)

    2008-07-15

    We sought to establish and characterize a mouse liver tumor model as a platform for preclinical assessment of new diagnostics and therapeutics. Radiation-induced fibrosarcoma (RIF-1) was intrahepatically implanted in 27 C3H/Km mice. Serial in vivo magnetic resonance imaging (MRI) with a clinical 1.5-T-magnet was performed using T1- (T1WI), T2- (T2WI), and diffusion-weighted sequences (DWI), dynamic contrast-enhanced MRI (DCE-MRI), and contrast-enhanced T1WI, and validated with postmortem microangiography and histopathology. Implantation procedure succeeded in 25 mice with 2 deaths from overdosed anesthesia or hypothermia. RIF-1 grew in 21 mice with volume doubling time of 2.55{+-}0.88 days and final size of 216.2{+-}150.4 mm{sup 3} at day 14. Three mice were found without tumor growth and one only with abdominal seeding. The intrahepatic RIF-1 was hypervascularized with negligible necrosis as shown on MRI, microangiography and histology. On DCE-MRI, maximal initial slope of contrast-time curve and volume transfer constant per unit volume of tissue, K, differed between the tumor and liver with only the former significantly lower in the tumor than in the liver (P<0.05). Liver implantation of RIF-1 in mice proves a feasible and reproducible model and appears promising for use to screen new diagnostics and therapeutics under noninvasive monitoring even with a clinical MRI system. (orig.)

  3. Murine liver implantation of radiation-induced fibrosarcoma: characterization with MR imaging, microangiography and histopathology

    International Nuclear Information System (INIS)

    Wang, Huaijun; Keyzer, Frederik de; Jin, Lixin; Yu, Jie; Marchal, Guy; Ni, Yicheng; Putte, Marie van de; Witte, Peter de; Chen, Feng

    2008-01-01

    We sought to establish and characterize a mouse liver tumor model as a platform for preclinical assessment of new diagnostics and therapeutics. Radiation-induced fibrosarcoma (RIF-1) was intrahepatically implanted in 27 C3H/Km mice. Serial in vivo magnetic resonance imaging (MRI) with a clinical 1.5-T-magnet was performed using T1- (T1WI), T2- (T2WI), and diffusion-weighted sequences (DWI), dynamic contrast-enhanced MRI (DCE-MRI), and contrast-enhanced T1WI, and validated with postmortem microangiography and histopathology. Implantation procedure succeeded in 25 mice with 2 deaths from overdosed anesthesia or hypothermia. RIF-1 grew in 21 mice with volume doubling time of 2.55±0.88 days and final size of 216.2±150.4 mm 3 at day 14. Three mice were found without tumor growth and one only with abdominal seeding. The intrahepatic RIF-1 was hypervascularized with negligible necrosis as shown on MRI, microangiography and histology. On DCE-MRI, maximal initial slope of contrast-time curve and volume transfer constant per unit volume of tissue, K, differed between the tumor and liver with only the former significantly lower in the tumor than in the liver (P<0.05). Liver implantation of RIF-1 in mice proves a feasible and reproducible model and appears promising for use to screen new diagnostics and therapeutics under noninvasive monitoring even with a clinical MRI system. (orig.)

  4. Spatially Fractionated Radiation Induces Cytotoxicity and Changes in Gene Expression in Bystander and Radiation Adjacent Murine Carcinoma Cells

    Science.gov (United States)

    Asur, Rajalakshmi S.; Sharma, Sunil; Chang, Ching-Wei; Penagaricano, Jose; Kommuru, Indira M.; Moros, Eduardo G.; Corry, Peter M.; Griffin, Robert J.

    2012-01-01

    Radiation-induced bystander effects have been extensively studied at low doses, since evidence of bystander induced cell killing and other effects on unirradiated cells were found to be predominant at doses up to 0.5 Gy. Therefore, few studies have examined bystander effects induced by exposure to higher doses of radiation, such as spatially fractionated radiation (GRID) treatment. In the present study, we evaluate the ability of GRID treatment to induce changes in GRID adjacent (bystander) regions, in two different murine carcinoma cell lines following exposure to a single irradiation dose of 10 Gy. Murine SCK mammary carcinoma cells and SCCVII squamous carcinoma cells were irradiated using a brass collimator to create a GRID pattern of nine circular fields 12 mm in diameter with a center-to-center distance of 18 mm. Similar to the typical clinical implementation of GRID, this is approximately a 50:50 ratio of direct and bystander exposure. We also performed experiments by irradiating separate cultures and transferring the medium to unirradiated bystander cultures. Clonogenic survival was evaluated in both cell lines to determine the occurrence of radiation-induced bystander effects. For the purpose of our study, we have defined bystander cells as GRID adjacent cells that received approximately 1 Gy scatter dose or unirradiated cells receiving conditioned medium from irradiated cells. We observed significant bystander killing of cells adjacent to the GRID irradiated regions compared to sham treated controls. We also observed bystander killing of SCK and SCCVII cells cultured in conditioned medium obtained from cells irradiated with 10 Gy. Therefore, our results confirm the occurrence of bystander effects following exposure to a high-dose of radiation and suggest that cell-to-cell contact is not required for these effects. In addition, the gene expression profile for DNA damage and cellular stress response signaling in SCCVII cells after GRID exposure was studied

  5. Biochemical analysis of murine leukemia viruses isolated from radiation-induced leukemias of strain BALB/c

    International Nuclear Information System (INIS)

    Ellis, R.W.; Hopkins, N.; Fleissner, E.

    1980-01-01

    Murine leukemia viruses isolated from radiation-induced BALB/c leukemias were characterized with respect to viral proteins and RNA. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the viral structural proteins revealed that for p12, p15, p30, and gp70, three to four electrophoretic variants of each could be detected. There was no correlation found between any of these mobilities and N- or B-tropism of the viruses. Proteins of all xenotropic viral isolates were identical in their gel electrophoretic profiles. The similar phenotypes of multiple viral clones from individual leukemias and of isolates grown in different cells suggest that the polymorphism of ecotropic viruses was generated in vivo rather than during in vitro virus growth. By two-dimensional fingerprinting of RNase T1-resistant oligonucleotides from 70S viral RNA, the previously reported association of N- and B-tropism with two distinct oligonucleotides was confirmed. The presence of two other oligonucleotides was correlated with positive and negative phenotypes of the virus-coded G/sub IX/ cell surface antigen. The RNAs of two B-tropic isolates with distinctive p15 and p12 phenotypes differed from the RNA of a prototype N-tropic virus by the absence of three oligonucleotides mapping in the 5' portion (gag region) of the prototype RNA. In addition, one small-plaque B-tropic virus displayed extensive changes in the RNA sequences associated with the env region of the prototype

  6. Properties of murine leukemia viruses produced by leukemic cells established from NIH Swiss mice with radiation-induced leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Okumoto, Masaaki; Nishikawa, Ryosuke; Takamori, Yasuhiko; Iwai, Yoshiaki; Iwai, Mineko [Radiation Center of Osaka Prefecture, Sakai (Japan); Imai, Shunsuke; Morimoto, Junji; Tsubura, Yoshihiko

    1984-06-01

    Three leukemic cell lines, designated NIH-RL1, NIH-RL2 and NFS-RL1, were established from spleen and thymuses of NIH Swiss and NFS mice with radiation-induced leukemia. The culture fluids of these cell lines contained RNA-dependent DNA polymerase (RDDP) activities associated with particles of buoyant density of 1.15-1.17 (g/cm/sup 3/). The divalent cation reqirement of these enzymes was characteristic for that of murine leukemia viruses. In competition radioimmunoassay, a major core protein, p30, was detected in culture fluid of each leukemic cell line. Competition curves of viral p30 produced by these cell lines revealed that these viruses were very similar to those of xenotropic viruses of NZB mice. These viruses were undetectable both by XC plaque assay using SC-1 cells as an indicator cell, and by mink S/sup +/L/sup -/ focus induction assay. These viruses also lacked productive infectivity to mink lung cells (CCL-64), and were nononcogenic in syngeneic mice when the viruses were intrathymically inoculated.

  7. A mathematical model for leukemogenesis of radiation-induced acute myeloid leukemia in C3H/He mice

    International Nuclear Information System (INIS)

    Kai, M.; Ban, N.

    2002-01-01

    We developed a mathematical model in leukemogenesis of acute myeloid leukemia(AML) in C3H/He mice irradiated. Our previous study indicated that the leukemogenesis of AML was associated with a deletion of chromosome 2 directly induced by acute radiation. We hypothesized that radiation-induced AML needs both inactivation of one allele of a causative gene directly induced by acute radiation and another mutational event at the other allele. We analyzed data using a two-stage stochastic model for carcinogenesis. Model fitting was based on the maximum likelihood method. Our model analysis suggested that a single exposure might induce the long-lasting delayed cell death of radiation-induced initiated cells, and that the incidence of AML may be determined through both radiation-induced initiation and persistent increase of delayed cell death of the initiated cell induced by radiation

  8. Radiation-induced chromosome aberrations in bone marrow cells leading to acute myeloid leukemia in mouse

    International Nuclear Information System (INIS)

    Nobuhiko Ban; Tomoko Kusama

    1996-01-01

    It is well known that radiation-induced acute myeloid leukemia (RI-AML) in mice is charaterized by deletion and/or rearrangement of chromosome 2. While chromosome 2 has been suspected to be a target of RI-AML, radiation-sensitive site of the chromosome might be implicated in the leukemogenesis. There were few cytogenetical studies, however, focusing on chromosomal rearrangements shortly after irradiation, and little was known about the frequency and pattern of chromosome 2 aberrations during the early period. In this study, metaphase samples were prepared from whole-body irradiated mice 24 hours after irradiation, most of the cells considered to be in the first mitotic stage. Distribution of chromosomal breakpoints on the metaphase samples were analyzed to study the relationship between chromosome aberrations and RI-AML. (author)

  9. Mammalian Target of Rapamycin Inhibition With Rapamycin Mitigates Radiation-Induced Pulmonary Fibrosis in a Murine Model

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eun Joo [Radiation Oncology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland (United States); Sowers, Anastasia; Thetford, Angela [Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland (United States); McKay-Corkum, Grace; Chung, Su I. [Radiation Oncology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland (United States); Mitchell, James B. [Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland (United States); Citrin, Deborah E., E-mail: citrind@mail.nih.gov [Radiation Oncology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland (United States)

    2016-11-15

    Purpose: Radiation-induced pulmonary fibrosis (RIPF) is a late toxicity of therapeutic radiation. Signaling of the mammalian target of rapamycin drives several processes implicated in RIPF, including inflammatory cytokine production, fibroblast proliferation, and epithelial senescence. We sought to determine if mammalian target of rapamycin inhibition with rapamycin would mitigate RIPF. Methods and Materials: C57BL/6NCr mice received a diet formulated with rapamycin (14 mg/kg food) or a control diet 2 days before and continuing for 16 weeks after exposure to 5 daily fractions of 6 Gy of thoracic irradiation. Fibrosis was assessed with Masson trichrome staining and hydroxyproline assay. Cytokine expression was evaluated by quantitative real-time polymerase chain reaction. Senescence was assessed by staining for β-galactosidase activity. Results: Administration of rapamycin extended the median survival of irradiated mice compared with the control diet from 116 days to 156 days (P=.006, log-rank test). Treatment with rapamycin reduced hydroxyproline content compared with the control diet (irradiation plus vehicle, 45.9 ± 11.8 μg per lung; irradiation plus rapamycin, 21.4 ± 6.0 μg per lung; P=.001) and reduced visible fibrotic foci. Rapamycin treatment attenuated interleukin 1β and transforming growth factor β induction in irradiated lungs compared with the control diet. Type II pneumocyte senescence after irradiation was reduced with rapamycin treatment at 16 weeks (3-fold reduction at 16 weeks, P<.001). Conclusions: Rapamycin protected against RIPF in a murine model. Rapamycin treatment reduced inflammatory cytokine expression, extracellular matrix production, and senescence in type II pneumocytes.

  10. Therapy and prophylaxis of acute and late radiation-induced sequelae of the esophagus

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, F.B.; Geinitz, H.; Feldmann, H.J. [Klinik und Poliklinik fuer Strahlentherapie und Radiologische Onkologie, Klinikum rechts der Isar, Muenchen (Germany)

    1998-11-01

    Background: Radiation-induced esophagitis is a frequent acute side effect in curative and palliative radiotherapy of thoracal and cervical tumors. Late reactions are rare but might be severe. Methods: A resarch for reports on prophylactic and supportive therapies of radiation-induced esophagitis was performed (Medline, Cancerlit, and others). Results: Nutrition must be ensured and symptomatic relief of sequelae is important, especially in the case of dysphagia. The latter can be improved by topic or systemic analgetics. If esophageal spasm occurs, calcium antagonists might help. In case of gastro-esophageal reflux proton pump inhibitors should be used. There is no effective prophylactic measure for radiation esophagitis. Late side effects with clinical relevance are rare in conventional radiotherapy. Chronic ulcera, fistula or stenosis may develop. Before any treatment, a tumor infiltration of the esophagus should be excluded by biopsy. This can lead more often to late complications than radiation therapy itself. Nutrition should be ensured by endoscopic dilation, stent-implantation, or endoscopic percutaneous gastrostomy. Local injection of steroids might be used to avoid an early restenosis. Conclusions: An intensive symptomatic therapy of acute esophagitis is reasonable. Effective prophylaxis do not exist. Late radiation induced sequelae is rare. Therefore, a tumor recurrenc e should be excluded in cases of dysphagia. Securing nutrition by PEG, stent, or port is well in the fore. (orig.) [Deutsch] Hintergrund: Die radiogene Oesophagitis ist eine haeufige akute Nebenwirkung bei kurativen wie palliativen Bestrahlungen thorakaler und zervikaler Tumoren. Spaete Gewebereaktionen sind selten, koennen aber schwerwiegend sein. Methode: Es wurde eine Literaturrecherche nach prophylaktischen und supportiven Therapien der radiogen verursachten Oesophagitis durchgefuehrt (Medline, Cancerlit und andere). Ergebnisse: Therapeutisch stehen die Sicherung der Ernaehrung und die

  11. Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

    International Nuclear Information System (INIS)

    Bouffler, S.D.; Breckon, G.; Cox, R.

    1996-01-01

    Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author)

  12. Protective effects of seabuckthorn pulp and seed oils against radiation-induced acute intestinal injury

    International Nuclear Information System (INIS)

    Shi, Jing; Wang, Lan; Lu, Yan; Ji, Yue; Wang, Yaqing; Dong, Ke; Kong, Xiangqing; Sun, Wei

    2017-01-01

    Radiation-induced gastrointestinal syndrome, including nausea, diarrhea and dehydration, contributes to morbidity and mortality after medical or industrial radiation exposure. No safe and effective radiation countermeasure has been approved for clinical therapy. In this study, we aimed to investigate the potential protective effects of seabuckthorn pulp and seed oils against radiation-induced acute intestinal injury. C57/BL6 mice were orally administered seabuckthorn pulp oil, seed oil and control olive oil once per day for 7 days before exposure to total-body X-ray irradiation of 7.5 Gy. Terminal deoxynucleotidyl transferase dUTP nick end labeling, quantitative real-time polymerase chain reaction and western blotting were used for the measurement of apoptotic cells and proteins, inflammation factors and mitogen-activated protein (MAP) kinases. Seabuckthorn oil pretreatment increased the post-radiation survival rate and reduced the damage area of the small intestine villi. Both the pulp and seed oil treatment significantly decreased the apoptotic cell numbers and cleaved caspase 3 expression. Seabuckthorn oil downregulated the mRNA level of inflammatory factors, including tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8. Both the pulp and seed oils elevated the level of phosphorylated extracellular-signal-regulated kinase and reduced the levels of phosphorylated c-Jun N-terminal kinase and p38. Palmitoleic acid (PLA) and alpha linolenic acid (ALA) are the predominant components of pulp oil and seed oil, respectively. Pretreatment with PLA and ALA increased the post-radiation survival time. In conclusion, seabuckthorn pulp and seed oils protect against mouse intestinal injury from high-dose radiation by reducing cell apoptosis and inflammation. ALA and PLA are promising natural radiation countermeasure candidates.

  13. Acute adaptive immune response correlates with late radiation-induced pulmonary fibrosis in mice

    International Nuclear Information System (INIS)

    Paun, Alexandra; Kunwar, Amit; Haston, Christina K

    2015-01-01

    The lung response to radiation exposure can involve an immediate or early reaction to the radiation challenge, including cell death and an initial immune reaction, and can be followed by a tissue injury response, of pneumonitis or fibrosis, to this acute reaction. Herein, we aimed to determine whether markers of the initial immune response, measured within days of radiation exposure, are correlated with the lung tissue injury responses occurring weeks later. Inbred strains of mice known to be susceptible (KK/HIJ, C57BL/6J, 129S1/SvImJ) or resistant (C3H/HeJ, A/J, AKR/J) to radiation-induced pulmonary fibrosis and to vary in time to onset of respiratory distress post thoracic irradiation (from 10–23 weeks) were studied. Mice were untreated (controls) or received 18 Gy whole thorax irradiation and were euthanized at 6 h, 1d or 7 d after radiation treatment. Pulmonary CD4+ lymphocytes, bronchoalveolar cell profile & cytokine level, and serum cytokine levels were assayed. Thoracic irradiation and inbred strain background significantly affected the numbers of CD4+ cells in the lungs and the bronchoalveolar lavage cell differential of exposed mice. At the 7 day timepoint greater numbers of pulmonary Th1 and Th17 lymphocytes and reduced lavage interleukin17 and interferonγ levels were significant predictors of late stage fibrosis. Lavage levels of interleukin-10, measured at the 7 day timepoint, were inversely correlated with fibrosis score (R = −0.80, p = 0.05), while serum levels of interleukin-17 in control mice significantly correlated with post irradiation survival time (R = 0.81, p = 0.04). Lavage macrophage, lymphocyte or neutrophil counts were not significantly correlated with either of fibrosis score or time to respiratory distress in the six mouse strains. Specific cytokine and lymphocyte levels, but not strain dependent lavage cell profiles, were predictive of later radiation-induced lung injury in this panel of inbred strains. The online version of this

  14. Study on bone marrow mesenchymal stem cells in repairing of radiation induced acute liver injury of rats

    International Nuclear Information System (INIS)

    Bao Yongxing; Lou Fan; Zhao Huarong; Zhu Huhu; Ma Yan; Wen Hao

    2010-01-01

    Objective: To investigate the role of mesenchymal stem cells in the repair of radiation induced liver injury. Methods: 12 female SD rats were irradiated with 20 Gy 6 MV X-rays on the right lobe of the liver, to establish the model of radiation induced liver injury. The rats were divided randomly into two groups as invention group and control group, and transplanted with 1 ml male mesenchymal suspension or 1 ml normal saline in 4 hours after radiotherapy. The morphological changes of liver were observed. The existence of sex determining gene Y(SRY) and the level of alpha-smooth muscle actin (a-SMA) were detected. Results: Some injury of right lobe liver in two groups were observed, and the injury degree of right lobe liver in intervention group were lower than that of control group. The amount of SRY positive cells in the right lobe liver of intervention group was higher than that in the left lobe liver (t = 3.77, P <0.05). The positive expression rate of a-SMA in right lobe liver of intervention group was lower than that of control group. Conclusions: Acute radiation induced liver injury could lead BMSCs' homing in order to decrease the degree of liver fibrosis. (authors)

  15. Gamma radiation induced oxidative stress and apoptosis inhibiting properties of bacterial secondary metabolite RK-IP-006.G in J774A.1 murine cell line

    International Nuclear Information System (INIS)

    Malhotra, Poonam; Gupta, Ashutosh K.; Singh, Praveen K.; Chhachhia, Neha; Singh, Shravan K.; Raj Kumar

    2014-01-01

    Redox imbalance due to radiation induced oxidation of vital bio-macromolecules activates inflammatory response cascade leading to cell death. In present study, bacterial secondary metabolite, RK-IP-006.G, was evaluated for its oxidative stress and apoptosis inhibiting activities in irradiated J774A.1 murine macrophage cell line. Radiation induced intracellular ROS generation and its inhibition upon RK-IP-006.G pretreatment was estimated using 2',7'dichlorodihydroflurescein diacetate (DCFDA). Modulation in mitochondrial membrane potential (MMP) in irradiated cells and its protection by RK-IP-006.G pretreatment was evaluated using Rhodamine-123. Modulation in protein expression in irradiated and RK-IP-006.G treated J774A.1 cells was assessed by SDS-PAGE. Compensatory effect of RK-IP-006.G treatment on TNF-α expression in irradiated cells was estimated using ELISA assay. APO-BrDU assay was performed to evaluate radiation-induced apoptosis in irradiated cells. Radiation-induced cell damage and protective ability of RK-IP-006.G was also evaluated using Differential Interference Contrast Microscopy. Results of the study indicated significant (p< 0.05) decrease in DCFDA fluorescence in irradiated cells that were pretreated (∼2h) with RK-IP-006.G (0.25 μg/ml) as compared to irradiated cells. Similarly, significant (p<0.05) decrease in MMP was observed in irradiated cells pretreated with RK-IP-006.G (0.25 μg/ml) as compared to only irradiated cells at 1 h time point. SDS-PAGE analysis clearly demonstrated up-regulation of some prominent proteins in irradiated cells pretreated with RK-IP-006.G at 2-4h after treatment as compared to irradiated control. Significant (p<0.05) down regulation in TNF-α expression was observed in irradiated cells that pretreated with RK-IP-006.G compared to irradiated controls. APO-BrDU assay revealed significant reduction in apoptosis in irradiated cells pretreated with RK-IP-006.G when compared to irradiated control. The findings

  16. The mouse small eye mutant, Del(2)Sey3H, which deletes the putative tumor suppressor region of the radiation-induced acute myeloid leukemia is susceptible to radiation

    International Nuclear Information System (INIS)

    Nitta, Yumiko; Yoshida, Kazuko; Tanaka, Kimio; Peters, Jo; Cattanach, Bruce M.

    2003-01-01

    Radiation-induced murine acute myeloid leukemia (AML) is characterized by the chromosome 2 deletions. Standing on the hypothesis that an AML suppressor gene would locate on the chromosome 2, a deletion-wide screen was performed on radiation-induced AMLs by the fluorescence in situ hybridization (FISH) method. The hemizugous deletion of the D2Mit15, a marker DNA at the 49.0cM region from the centromere, associated with the AMLs in 97 out of the 105 cases (92.4%). As the deletion region was close to the region of human WAGR syndrome (MIM194072), the mouse small eye mutants could be the animal model for radiation-induced AMLs. The mutant, Del(2)Sey3H (Sey3H) was found to delete around the 49.0cM region by the allelic loss mapping. The Sey3H showed high susceptibility to radiation to develop tumors including the myeloid leukemia with shorter latency. These finding support the existence of a putative tumor suppressor gene responsible for the radiation-leukemogenesis near the D2Mit15 region. (author)

  17. Inhibitory effect of magnesium sulfate on reaction of lipid hyperoxidation after radiation-induced acute brain injuries

    International Nuclear Information System (INIS)

    Wang Lili; Zhou Juying; Yu Zhiying; Qin Songbing; Xu Xiaoting; Li Li; Tu Yu

    2007-01-01

    Objective: To explore the protection of magnesium sulfate (MgSO 4 ) on radiation-induced acute brain injuries. Methods: 60 maturity Sprague-Dawley (SD) rats were randomly divided into 3 groups: blank control group, experimental control group and experimental-therapeutic group. The whole brain of SD rats of experimental control group and experimental-therapeutic group was irradiated to a dose of 20 Gy using 6 MeV electron. MgSO 4 was injected intraperitoneally into the rats of experimental-therapeutic group before and after irradiation for five times. At different time points ranging from the 1 d, 7 d, 14 d, 30 d after irradiation, the brain tissue were taken. The xanthine oxidase and colorimetric examination were used to measure the superoxide dismutase (SOD) and malonyldialdehyde (MDA) respectively in the rat brain respectively. Results: Compared with blank control group, the SOD in brain of experimental control group decreased significantly (P 4 used in early stage can inhibit the lipid peroxidation after radiation-induced acute brain injuries and alleviate the damage induced by free radicals to brain tissue. (authors)

  18. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hemopoietic injury

    International Nuclear Information System (INIS)

    Grande Azanedo, M.T.

    1988-01-01

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e. radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU- S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hemopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S) are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation. (Author)

  19. Bone marrow stem cells assuage radiation-induced damage in a murine model of distraction osteogenesis: A histomorphometric evaluation.

    Science.gov (United States)

    Zheutlin, Alexander R; Deshpande, Sagar S; Nelson, Noah S; Kang, Stephen Y; Gallagher, Kathleen K; Polyatskaya, Yekaterina; Rodriguez, Jose J; Donneys, Alexis; Ranganathan, Kavitha; Buchman, Steven R

    2016-05-01

    The purpose of this study is to determine if intraoperatively placed bone marrow stem cells (BMSCs) will permit successful osteocyte and mature bone regeneration in an isogenic murine model of distraction osteogenesis (DO) following radiation therapy (XRT). Lewis rats were split into three groups, DO only (Control), XRT followed by DO (xDO) and XRT followed by DO with intraoperatively placed BMSCs (xDO-BMSC). Coronal sections from the distraction site were obtained, stained and analyzed via statistical analysis with analysis of variance (ANOVA) and subsequent Tukey or Games-Howell post-hoc tests. Comparison of the xDO-BMSC and xDO groups demonstrated significantly improved osteocyte count (87.15 ± 10.19 vs. 67.88 ± 15.38, P = 0.00), and empty lacunae number (2.18 ± 0.79 vs 12.34 ± 6.61, P = 0.00). Quantitative analysis revealed a significant decrease in immature osteoid volume relative to total volume (P = 0.00) and improved the ratio of mature woven bone to immature osteoid (P = 0.02) in the xDO-BMSC compared with the xDO group. No significant differences were found between the Control and xDO-BMSC groups. In an isogenic murine model of DO, BMSC therapy assuaged XRT-induced cellular depletion, resulting in a significant improvement in histological and histomorphometric outcomes. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  20. Cell kinetics of hypoxic cells in a murine tumour in vivo: flow cytometric determination of the radiation-induced blockage of cell cycle progression

    International Nuclear Information System (INIS)

    Rutgers, D.H.; Niessen, D.P.P.; Linden, P.M. van der

    1987-01-01

    Cells from the small cell population of viable cells in the large necrotic centre of murine M8013 tumours were investigated with respect to their cell kinetics. Flow cytometry (FCM) of this part of subcutaneously transplanted tumours revealed the presence of tumour cells with G1,S and G2 + M phase DNA-contents. These severely hypoxic cells could have stopped cell cycle progression due to the nutritional deprivation, irrespective of their position within the cell cycle. Labelling methods, used to disclose the cell kinetics of this cell population, are hampered by the absence of a transport system in these large necrotic areas. Therefore FCM was used to monitor radiation induced changes in the cell cycle distribution. From this investigation it was concluded that hypoxic cells in the necrotic centre of the M8013 tumour progress through the cell cycle. As well as a cell population with a cell cycle time (Tsub(c)) of approximately 84 hr, a subpopulation with a Tsub(c) of approximately 21 hr occurred. (author)

  1. Treatment plan of acute radiation-induced skin injuries with special reference to an accidentally exposed case

    International Nuclear Information System (INIS)

    Yoshizawa, Yasuo; Kusama, Tomoko

    1977-01-01

    Description was made as to clinical cource of one case of acute radiation-induced skin injury and practical use of medical treatment plan for radiation-induced skin injuries. The accident occurred during the working (5 o'clock in the afternoon) on development of x-ray tube for x-ray fluorescent analysis apparatus. The condition of x-ray exposure was 50 KeV and 10 mA, and the window of x-ray tube was Be 0.3 mm in thickness. The exposure time was about 5 seconds, and the exposure dose on the palm of the right hand which was the maximum was estimated as 10,000 rads. In the next morning after the exposure, the patient complained of extension feeling and edema in the palm of the right hand, and redness and blister appeared. On 11 days after the exposure, blister and edematous swelling grew to the greatest, and pain was emphasized. On 15 days after the exposure, tendency of cure appeared, and on 20 days after, pigmentation became marked. Main symptoms of local findings of one year and half after the exposure were skin atrophy, dilatation of capillary vessels, and depigmentation. The strict local rest, the protection from stimulations outside, the use of medicines for external application in which additives were small in quantity, the frequent and detailed local observation and detailed life guidance were mentioned as basic policies in the early treatment. Avoidance of the skin dryness, local observation with proper frequency, protection from stimulations outside, and life guidance were mentioned as basic policies during the period while the symptoms were fixed. In case of acute exposure, the importance of early treatment and necessity of endeavour of preventing delayed disturbances such as chronic ulcer and carcinogenesis were mentioned. (Tsunoda, M.)

  2. The histopathological comparison of L-carnitine with amifostine for protective efficacy on radiation-induced acute small intestinal toxicity

    Directory of Open Access Journals (Sweden)

    Murat Caloglu

    2012-01-01

    Full Text Available Background: The aim of the study was to compare the protective efficacy of l-carnitine (LC to amifostine on radiation-induced acute small intestine damage. Materials and Methods: Thirty, 4-week-old Wistar albino rats were randomly assigned to four groups - Group 1: control (CONT, n = 6, Group 2: irradiation alone (RT, n = 8, Group 3: amifostine plus irradiation (AMI+RT, n = 8, and Group 4: l-Carnitine plus irradiation (LC+RT, n = 8. The rats in all groups were irradiated individually with a single dose of 20 Gy to the total abdomen, except those in CONT. LC (300 mg/kg or amifostine (200 mg/kg was used 30 min before irradiation. Histopathological analysis of small intestine was carried out after euthanasia. Results: Pretreatment with amifostine reduced the radiation-induced acute degenerative damage (P = 0.009 compared to the RT group. Pretreatment with LC did not obtain any significant difference compared to the RT group. The vascular damage significantly reduced in both of the AMI+RT (P = 0.003 and LC+RT group (P = 0.029 compared to the RT group. The overall damage score was significantly lower in the AMI+RT group than the RT group (P = 0.009. There was not any significant difference between the LC+RT and RT group. Conclusions: Amifostine has a marked radioprotective effect against all histopathological changes on small intestinal tissue while LC has limited effects which are mainly on vascular structure.

  3. Treatment plan of acute radiation-induced skin injuries with special reference to an accidentally exposed case

    Energy Technology Data Exchange (ETDEWEB)

    Yashizawa, Y; Kusama, T [Tokyo Univ. (Japan). Faculty of Medicine

    1977-05-01

    Description was made as to clinical cource of one case of acute radiation-induced skin injury and practical use of medical treatment plan for radiation-induced skin injuries. The accident occurred during the working (5 o'clock in the afternoon) on development of x-ray tube for x-ray fluorescent analysis apparatus. The condition of x-ray exposure was 50 KeV and 10 mA, and the window of x-ray tube was Be 0.3 mm in thickness. The exposure time was about 5 seconds, and the exposure dose on the palm of the right hand which was the maximum was estimated at 10,000 rads. In the next morning after the exposure, the patient complained of extension feeling and edema in the palm of the right hand, and redness and blister appeared. On 11 days after the exposure, blister and edematous swelling grew to the greatest, and pain was emphasized. On 15 days after the exposure, tendency of cure appeared, and on 20 days after, pigmentation became marked. Main symptoms of local findings of one year and half after the exposure were skin atrophy, dilatation of capillary vessels, and depigmentation. The strict local rest, the protection from stimulations outside, the use of medicines for external application in which additives were small in quantity, the frequent and detailed local observation and detailed life guidance were mentioned as basic policies in the early treatment. Avoidance of the skin dryness, local observation with proper frequency, protection from stimulations outside, and life guidance were mentioned as basic policies during the period while the symptoms were fixed. In case of acute exposure, the importance of early treatment and necessity of endeavour of preventing delayed disturbances such as chronic ulcer and carcinogenesis were mentioned.

  4. Identification of proteins that regulate radiation-induced apoptosis in murine tumors with wild type p53

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Jinsil; Oh, Hae Jin; Kim, Jiyoung; An, Jeung Hee; Kim, Wonwoo [Dept. of Radiation Oncology, Yonsei Univ. Medical College, Seoul (Korea, Republic of)

    2007-09-15

    In this study, we investigated the molecular factors determining the induction of apoptosis by radiation. Two murine tumors syngeneic to C3H/HeJ mice were used: an ovarian carcinoma OCa-I, and a hepatocarcinoma HCa-I. Both have wild type p53, but display distinctly different radiosensitivity in terms of specific growth delay (12.7 d in OCa-I and 0.3 d in HCa-I) and tumor cure dose 50% (52.6 Gy in OCa-I and >80 Gy in HCa-I). Eight-mm tumors on the thighs of mice were irradiated with 25 Gy and tumor samples were collected at regular time intervals after irradiation. The peak levels of apoptosis were 16.1{+-}0.6% in OCa-I and 0.2{+-}0.0% in HCa-I at 4 h after radiation, and this time point was used for subsequent proteomics analysis. Protein spots were identified by peptide mass fingerprinting with a focus on those related to apoptosis. In OCa-I tumors, radiation increased the expression of cytochrome c oxidase and Bcl2/adenovirus E1B-interacting 2 (Nip 2) protein higher than 3-fold. However in HCa-I, these two proteins showed no significant change. The results suggest that radiosensitivity in tumors with wild type p53 is regulated by a complex mechanism. Furthermore, these proteins could be molecular targets for a novel therapeutic strategy involving the regulation of radiosensitivity. (author)

  5. Identification of proteins that regulate radiation-induced apoptosis in murine tumors with wild type p53

    International Nuclear Information System (INIS)

    Seong, Jinsil; Oh, Hae Jin; Kim, Jiyoung; An, Jeung Hee; Kim, Wonwoo

    2007-01-01

    In this study, we investigated the molecular factors determining the induction of apoptosis by radiation. Two murine tumors syngeneic to C3H/HeJ mice were used: an ovarian carcinoma OCa-I, and a hepatocarcinoma HCa-I. Both have wild type p53, but display distinctly different radiosensitivity in terms of specific growth delay (12.7 d in OCa-I and 0.3 d in HCa-I) and tumor cure dose 50% (52.6 Gy in OCa-I and >80 Gy in HCa-I). Eight-mm tumors on the thighs of mice were irradiated with 25 Gy and tumor samples were collected at regular time intervals after irradiation. The peak levels of apoptosis were 16.1±0.6% in OCa-I and 0.2±0.0% in HCa-I at 4 h after radiation, and this time point was used for subsequent proteomics analysis. Protein spots were identified by peptide mass fingerprinting with a focus on those related to apoptosis. In OCa-I tumors, radiation increased the expression of cytochrome c oxidase and Bcl2/adenovirus E1B-interacting 2 (Nip 2) protein higher than 3-fold. However in HCa-I, these two proteins showed no significant change. The results suggest that radiosensitivity in tumors with wild type p53 is regulated by a complex mechanism. Furthermore, these proteins could be molecular targets for a novel therapeutic strategy involving the regulation of radiosensitivity. (author)

  6. Quantitative assay for the number of leukemic spleen colony forming unit in radiation-induced murine myeloid leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Nara, N [Tokyo Medical and Dental Univ. (Japan). School of Medicine; Bessho, M

    1981-11-01

    In mice with myelogenous leukemia, leukemic spleen colony forming units were assayed quantitatively. When 5 x 10/sup 3/ - 2 x 10/sup 4/ leukemic cells were transplanted to other mice of the same strain, a rectilinear relationship (p < 0.01) was found between the number of the cells transplanted and that of the colonies formed on the surface of the spleen. From these results, the authors considered that myelogenous leukemia in mice is an adequate model for acute myelogenous leukemia in human adults, and that the quantitative assay of the leukemic colony forming units can be used for sensitivity tests of antileukemic agents.

  7. Radiation-induced acute necrosis of the pancreatic islet and the diabetic syndrome in the golden hamster (Mesocricetus auratus)

    Energy Technology Data Exchange (ETDEWEB)

    Tsubouchi, S; Suzuki, H; Ariyoshi, H [Aichi Cancer Center, Nagoya (Japan); Matsuzawa, T [Tohoku Univ., Sendai (Japan). Research Inst. for Tuberculosis and Cancer

    1981-07-01

    Exposure of golden hamsters to 35 000 rad of X-rays induced acute and specific necrosis of the cells of the islets of Langerhans of the pancreas within 4 hours, whereas no other tissue revealed any drastic changes which would lead to a critical illness until 36 hours. Animals began to show the characteristic signs of diabetes, that is, hyperglycaemia, hyperkalaemia, ketonemia, and acidosis at 12 hours and these continued until death, 56+-8 hours later. These were accompanied by the disappearance of ..beta..-cell granules and a decrease of plasma insulin. Treatment of irradiated animals with injections of insulin resulted in a reduction in high blood glucose and the prolongation of survival time up to 5 days, which is comparable to the survival time when the cause of death is gastrointestinal. It is concluded that this radiation-induced diabetic syndrome resulted from acute necrosis of the cells of the islets of Langerhans, a previously unreported lethal effect of radiation in golden hamsters.

  8. Moist skin care can diminish acute radiation-induced skin toxicity

    International Nuclear Information System (INIS)

    Momm, F.; Weissenberger, C.; Bertelt, S.; Henke, M.

    2003-01-01

    Background: Radiation treatment may induce acute skin reactions. There are several methods of managing them. Validity of these methods, however, is not sufficiently studied. We therefore investigated, whether moist skin care with 3% urea lotion will reduce acute radiation skin toxicity. Patients and Methods: 88 patients with carcinomas of the head and neck undergoing radiotherapy with curative intent (mean total dose 60 Gy, range: 50-74 Gy) were evaluated weekly for acute skin reactions according to the RTOG-CTC score. In 63 patients, moist skin care with 3% urea lotion was performed. The control group consisted of 25 patients receiving conventional dry skin care. The incidence of grade I, II, and III reactions and the radiation dose at occurrence of a particular reaction were determined and statistically analyzed using the log-rank test. The dose-time relations of individual skin reactions are described. Results: At some point of time during radiotherapy, all patients suffered from acute skin reactions grade I, > 90% from grade II reactions. 50% of patients receiving moist skin care experienced grade I reactions at 26 Gy as compared to 22 Gy in control patients (p = 0.03). Grade II reactions occurred at 51 Gy versus 34 Gy (p = 0.006). Further, 22% of the patients treated with moist skin care suffered from acute skin toxicity grade III as compared to 56% of the controls (p = 0.0007). Conclusion: Moist skin care with 3% urea lotion delays the occurrence and reduces the grade of acute skin reactions in percutaneously irradiated patients with head and neck tumors. (orig.)

  9. Radiation-induced acute dysphagia. Prospective observational study on 42 head and neck cancer patients

    International Nuclear Information System (INIS)

    Alterio, D.; Gerardi, M.A.; Fodor, C.; Ciardo, D.; Ferrari, A.; Colangione, S.; Cella, L.; D'Avino, V.; Conson, M.; Palma, G.; Spoto, R.; Dicuonzo, S.; Jereczek-Fossa, B.A.; Zurlo, V.; Bruschini, R.; Sabbatini, A.; Valoriani, F.; Pacelli, R.; Maisonneuve, P.; Preda, L.; Cossu Rocca, M.; Rondi, E.; Orecchia, R.; Sanguineti, G.

    2017-01-01

    Acute toxicity in head and neck (H and N) cancer patients treated with definitive radiotherapy (RT) has a crucial role in compliance to treatments. The aim of this study was to correlate doses to swallowing-associated structures and acute dysphagia. We prospectively analyzed 42 H and N cancer patients treated with RT. Dysphagia (grade ≥ 3) and indication for percutaneous endoscopic gastrostomy (PEG) insertion were classified as acute toxicity. Ten swallowing-related structures were considered for the dosimetric analysis. The correlation between clinical information and the dose absorbed by the contoured structures was analyzed. Multivariate logistic regression method using resampling methods (bootstrapping) was applied to select model order and parameters for normal tissue complication probability (NTCP) modelling. A strong multiple correlation between dosimetric parameters was found. A two-variable model was suggested as the optimal order by bootstrap method. The optimal model (Rs = 0.452, p < 0.001) includes V 45 of the cervical esophagus (odds ratio [OR] = 1.016) and D mean of the cricopharyngeal muscle (OR = 1.057). The model area under the curve was 0.82 (95% confidence interval 0.69-0.95). Our results suggested that the absorbed dose to the cricopharyngeal muscle and cervical esophagus might play a relevant role in the development of acute RT-related dysphagia. (orig.) [de

  10. Immunomodulatory effects of high-protein diet with resveratrol supplementation on radiation-induced acute-phase inflammation in rats.

    Science.gov (United States)

    Kim, Kyoung-Ok; Park, HyunJin; Chun, Mison; Kim, Hyun-Sook

    2014-09-01

    We hypothesized that a high-protein diet and/or resveratrol supplementation will improve acute inflammatory responses in rats after receiving experimental abdominal radiation treatment (ART). Based on our previous study, the period of 10 days after ART was used as an acute inflammation model. Rats were exposed to a radiation dose of 17.5 Gy and were supplied with a control (C), 30% high-protein diet (HP), resveratrol supplementation (RES), or HP with RES diet ([HP+RES]). At day 10 after ART, we measured profiles of lipids, proteins, and immune cells in blood. The levels of clusters of differentiating 4(+) (CD4(+)) cells and regulatory T cells, serum proinflammatory cytokines, and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urine were also measured. ART caused significant disturbances of lipid profiles by increasing triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C), and decreasing high-density lipoprotein cholesterol. The proinflammatroy cytokine levels were also increased by ART. All the experimental diets (HP, RES, and [HP+RES]) significantly decreased levels of TG, monocytes, proinflammatory cytokines, and 8-OHdG, whereas the platelet counts were increased. In addition, the HP and [HP+RES] diets decreased the concentrations of plasma LDL-C and total cholesterol. Also, the HP and RES diets decreased regulatory T cells compared with those of the control diet in ART group. Further, the HP diet led to a significant recovery of white blood cell counts, as well as increased percentages of lymphocyte and decreased percentages of neutrophils. In summary, RES appeared to be significantly effective in minimizing radiation-induced damage to lipid metabolism and immune responses. Our study also demonstrated the importance of dietary protein intake in recovering from acute inflammation by radiation.

  11. Does granulocyte colony-stimulating factor exacerbate radiation-induced acute lung injury in rats?

    International Nuclear Information System (INIS)

    Miura, Gouji; Awaya, Hitomi; Matsumoto, Tsuneo; Tanaka, Nobuyuki; Matsunaga, Naofumi

    2000-01-01

    Radiation pneumonitis (RP) frequently occurs as a complication of thoracic irradiation. However, the mechanism of RP is not well known. Activated neutrophils are a possible pathogenesis of RP. Neutrophil activation induced by granulocyte colony-stimulating factor (G-CSF) may exacerbate RP. We studied the effects of recombinant human G-CSF on acute lung injury induced by thoracic irradiation using rats. Animals were divided into three groups: sham irradiation with saline control, irradiation alone, and irradiation with G-CSF. Actual irradiation was given as a single fraction of 16 Gy delivered to the right hemithorax. G-CSF at a dose of 12 μg/body was administered subcutaneously once a day from 14 to 18 days after actual irradiation. Lung injury was evaluated 21 days after irradiation by bronchoalveolar lavage (BAL) fluid findings and the lung wet/dry weight (W/D) ratio. Neutrophil and lymphocyte counts in BAL fluid and the W/D ratio were significantly increased in the irradiation alone and the irradiation with G-CSF groups compared with those of the sham irradiation+saline control group. However, there was no significant difference observed between the irradiation alone and irradiation with G-CSF groups. In conclusion, this study suggests that postradiation administration of G-CSF does not exacerbate acute lung injury induced by thoracic irradiation in rats. (author)

  12. Does granulocyte colony-stimulating factor exacerbate radiation-induced acute lung injury in rats?

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Gouji; Awaya, Hitomi; Matsumoto, Tsuneo; Tanaka, Nobuyuki; Matsunaga, Naofumi [Yamaguchi Univ., Ube (Japan). School of Medicine

    2000-08-01

    Radiation pneumonitis (RP) frequently occurs as a complication of thoracic irradiation. However, the mechanism of RP is not well known. Activated neutrophils are a possible pathogenesis of RP. Neutrophil activation induced by granulocyte colony-stimulating factor (G-CSF) may exacerbate RP. We studied the effects of recombinant human G-CSF on acute lung injury induced by thoracic irradiation using rats. Animals were divided into three groups: sham irradiation with saline control, irradiation alone, and irradiation with G-CSF. Actual irradiation was given as a single fraction of 16 Gy delivered to the right hemithorax. G-CSF at a dose of 12 {mu}g/body was administered subcutaneously once a day from 14 to 18 days after actual irradiation. Lung injury was evaluated 21 days after irradiation by bronchoalveolar lavage (BAL) fluid findings and the lung wet/dry weight (W/D) ratio. Neutrophil and lymphocyte counts in BAL fluid and the W/D ratio were significantly increased in the irradiation alone and the irradiation with G-CSF groups compared with those of the sham irradiation+saline control group. However, there was no significant difference observed between the irradiation alone and irradiation with G-CSF groups. In conclusion, this study suggests that postradiation administration of G-CSF does not exacerbate acute lung injury induced by thoracic irradiation in rats. (author)

  13. Feasibility of using optical coherence tomography to detect acute radiation-induced esophageal damage in small animal models

    Science.gov (United States)

    Jelvehgaran, Pouya; de Bruin, Daniel Martijn; Salguero, F. Javier; Borst, Gerben Roelof; Song, Ji-Ying; van Leeuwen, Ton G.; de Boer, Johannes F.; Alderliesten, Tanja; van Herk, Marcel

    2018-04-01

    Lung cancer survival is poor, and radiation therapy patients often suffer serious treatment side effects. The esophagus is particularly sensitive leading to acute radiation-induced esophageal damage (ARIED). We investigated the feasibility of optical coherence tomography (OCT) for minimally invasive imaging of the esophagus with high resolution (10 μm) to detect ARIED in mice. Thirty mice underwent cone-beam computed tomography imaging for initial setup assessment and dose planning followed by a single-dose delivery of 4.0, 10.0, 16.0, and 20.0 Gy on 5.0-mm spots, spaced 10.0 mm apart in the esophagus. They were repeatedly imaged using OCT up to three months postirradiation. We compared OCT findings with histopathology obtained three months postirradiation qualitatively and quantitatively using the contrast-to-background-noise ratio (CNR). Histopathology mostly showed inflammatory infiltration and edema at higher doses; OCT findings were in agreement with most of the histopathological reports. We were able to identify the ARIED on OCT as a change in tissue scattering and layer thickness. Our statistical analysis showed significant difference between the CNR values of healthy tissue, edema, and inflammatory infiltration. Overall, the average CNR for inflammatory infiltration and edema damages was 1.6-fold higher and 1.6-fold lower than for the healthy esophageal wall, respectively. Our results showed the potential role of OCT to detect and monitor the ARIED in mice, which may translate to humans.

  14. Endovascular treatment of radiation-induced petrous internal carotid artery aneurysm presenting with acute haemorrhage. A report of two cases

    International Nuclear Information System (INIS)

    Cheng, K.-M.; Chiu, H.-M.; Chan, C.-M.; Cheung, Y.-L.; Tang, K.-W.; Law, C.-K.

    2001-01-01

    Hemorrhage from rupture of petrous ICA aneurysm can be life threatening and emergency treatment is required. We report 2 cases of radiation-induced petrous internal carotid artery (ICA) aneurysm presenting with acute hemorrhage (epistaxis and otorrhagia) after radiotherapy (RT) for nasopharyngeal carcinoma (NPC). Both patients had a history of RT treatment for NPC. The first patient, a 54-year-old man, presented with sudden severe epistaxis and hemorrhagic shock. The second patient, a 35-year-old man, presented with episodes of severe otorrhagia. The first patient was immediately resuscitated. Obliteration of the aneurysm was performed by endovascular occlusion of the ICA with Guglielmi detachable coils and fibered platinum coils. For the second patient, the aneurysm was treated by deploying a self-expandable stent across the aneurysm neck. In an emergency situation, ruptured petrous ICA aneurysm can be treated with endovascular occlusion of the ICA with micro-coils if there is a good collateral blood flow. Alternatively, the aneurysm can be treated by deployment of a stent, which can induce stasis and eventual thrombosis of the aneurysm. (author)

  15. Radiation-induced acute dysphagia. Prospective observational study on 42 head and neck cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Alterio, D.; Gerardi, M.A.; Fodor, C.; Ciardo, D.; Ferrari, A.; Colangione, S. [European Institute of Oncology, Department of Radiotherapy, Milan (Italy); Cella, L.; D' Avino, V.; Conson, M.; Palma, G. [National Research Council (CNR), Institute of Biostructures and Bioimaging, Naples (Italy); Spoto, R.; Dicuonzo, S.; Jereczek-Fossa, B.A. [European Institute of Oncology, Department of Radiotherapy, Milan (Italy); University of Milan, Department of Oncology and Hemato-oncology, Milan (Italy); Zurlo, V.; Bruschini, R. [European Institute of Oncology, Division of Head and Neck Surgery, Milan (Italy); Sabbatini, A.; Valoriani, F. [European Institute of Oncology, Dietetic and Clinical Nutrition Unit, Milan (Italy); Pacelli, R. [National Research Council (CNR), Institute of Biostructures and Bioimaging, Naples (Italy); Federico II University School of Medicine, Department of Advanced Biomedical Sciences, Naples (Italy); Maisonneuve, P. [European Institute of Oncology, Department of Epidemiology and Statistics, Milan (Italy); Preda, L. [European Institute of Oncology, Department of Radiology, Milan (Italy); Cossu Rocca, M. [European Institute of Oncology, Division of Urogenital and Head and Neck Tumors, Department of Medical Oncology, Milan (Italy); Rondi, E. [European Institute of Oncology, Unit of Medical Physics, Milan (Italy); Orecchia, R. [European Institute of Oncology, Scientific Directorate, Milan (Italy); Sanguineti, G. [Istituto Tumori Regina Elena, Rome (Italy)

    2017-11-15

    Acute toxicity in head and neck (H and N) cancer patients treated with definitive radiotherapy (RT) has a crucial role in compliance to treatments. The aim of this study was to correlate doses to swallowing-associated structures and acute dysphagia. We prospectively analyzed 42 H and N cancer patients treated with RT. Dysphagia (grade ≥ 3) and indication for percutaneous endoscopic gastrostomy (PEG) insertion were classified as acute toxicity. Ten swallowing-related structures were considered for the dosimetric analysis. The correlation between clinical information and the dose absorbed by the contoured structures was analyzed. Multivariate logistic regression method using resampling methods (bootstrapping) was applied to select model order and parameters for normal tissue complication probability (NTCP) modelling. A strong multiple correlation between dosimetric parameters was found. A two-variable model was suggested as the optimal order by bootstrap method. The optimal model (Rs = 0.452, p < 0.001) includes V{sub 45} of the cervical esophagus (odds ratio [OR] = 1.016) and D{sub mean} of the cricopharyngeal muscle (OR = 1.057). The model area under the curve was 0.82 (95% confidence interval 0.69-0.95). Our results suggested that the absorbed dose to the cricopharyngeal muscle and cervical esophagus might play a relevant role in the development of acute RT-related dysphagia. (orig.) [German] Bei Kopf-Hals-Tumorpatienten, die mit einer kurativen Strahlentherapie (''radiation therapy'', RT) behandelt werden, spielt die Akuttoxizitaet eine entscheidende Rolle fuer die Patientencompliance bei der Behandlung. Ziel dieser Studie war es, die Dosen im Bereich des Schluckapparates mit der akuten Dysphagie zu korrelieren. Prospektiv analysiert wurden 42 mit einer RT behandelten Patienten. Eine Dysphagie III und/oder die Indikation fuer eine PEG(perkutane endoskopische Gastrostomie)-Anlage wurden als Akuttoxizitaet klassifiziert. Fuer die dosimetrische

  16. Updated assessment of the six-minute walk test as predictor of acute radiation-induced pneumonitis

    International Nuclear Information System (INIS)

    Mao Jingfang; Zhang Junan; Zhou Sumin; Das, Shiva; Hollis, Donna R.; Folz, Rodney J.; Wong, Terence Z.; Marks, Lawrence B.

    2007-01-01

    Purpose: To assess the utility of the 6-minute walk test (6MWT) as a predictor of symptomatic radiation-induced pneumonitis (RP). Methods: As part of a prospective trial to study radiation-induced lung injury, 53 patients receiving thoracic radiotherapy (RT) underwent a pre-RT 6MWT, pulmonary function tests (PFTs), and had ≥3-month follow-up for prospective assessment of Grade 2 or worse RP (requiring medications or worse). Dosimetric parameters (e.g., the percentage of lung receiving ≥30 Gy) were extracted from the lung dose-volume histogram. The correlations between the 6MWT and PFT results were assessed using Pearson's correlation. The receiver operating characteristic technique was used in patient subgroups to evaluate the predictive capacities for RP of the dosimetric parameters, 6MWT results, and PFT results, or the combination (using discriminant analysis) of all three metrics. ROCKIT software was used to compare the receiver operating characteristic areas between each predictive model. The association of the decline in 6MWT with the development of RP was evaluated using Fisher's exact test. Results: The pre-RT PFT and 6MWT results correlated weakly (r = 0.44-0.57, p ≤ 0.001), suggesting that they measure somewhat different physiologic functions. Of the 53 patients, 9 (17%) developed RP. The dose-volume histogram-based dosimetric parameters were the best single-metric model for predicting RP (e.g., percentage of lung receiving ≥30 Gy, receiver operating characteristic area 0.73, p = 0.03). Including the PFT or 6MWT results with the percentage of lung receiving ≥30 Gy did not improve the predictions. The predictive abilities of dosimetric-based models improved when the analysis was restricted to those patients whose tumors were not causing regional lung dysfunction. No correlation was found between the decline in the 6MWT result and the RP rate (p = 0.6). Conclusion: Although the PFTs and 6MWT are related to each other, the correlation coefficients

  17. Identification of biomarkers for radiation-induced acute intestinal symptoms (RIAISs) in cervical cancer patients by serum protein profiling

    International Nuclear Information System (INIS)

    Chai Yanlan; Wang Juan; Gao Ying

    2015-01-01

    Radiation-induced acute intestinal symptoms (RIAISs) are the most frequent complication of radiotherapy that causes great pain and limits the treatment efficacy. The aim of this study was to identify serum biomarkers of RIAISs in cervical cancer patients by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). Serum samples were collected from 66 cervical cancer patients prior to pelvic radiotherapy. In our study, RIAISs occurred in 11 patients. An additional 11 patients without RIAISs were selected as controls, whose age, stage, histological type and treatment methods were matched to RIAISs patients. The 22 sera were subsequently analyzed by SELDI-TOF MS, and the resulting protein profiles were evaluated to identify biomarkers using appropriate bioinformatics tools. Comparing the protein profiles of serum samples from the RIAIS group and the control group, it was found that 22 protein peaks were significantly different (P < 0.05), and six of these peaks with mass-to-charge (m/z) ratios of 7514.9, 4603.94, 6887.41, 2769.21, 3839.72 and 4215.7 were successfully identified. A decision tree model of biomarkers was constructed based on three biomarkers (m/z 1270.88, 1503.23 and 7514.90), which separated RIAIS-affected patients from the control group with an accuracy of 81%. This study suggests that serum proteomic analysis by SELDI-TOF MS can identify cervical cancer patients that are susceptible to RIAISs prior to pelvic radiotherapy. (author)

  18. A prospective phase II trial of EGCG in treatment of acute radiation-induced esophagitis for stage III lung cancer

    International Nuclear Information System (INIS)

    Zhao, Hanxi; Xie, Peng; Li, Xiaolin; Zhu, Wanqi; Sun, Xindong; Sun, Xiaorong; Chen, Xiaoting; Xing, Ligang; Yu, Jinming

    2015-01-01

    Background: Acute radiation-induced esophagitis (ARIE) is one of main toxicities complicated by thoracic radiotherapy, influencing patients’ quality of life and radiotherapy proceeding seriously. It is difficult to be cured rapidly so far. Our phase I trial preliminarily showed that EGCG may be a promising strategy in the treatment of ARIE. Materials and methods: We prospectively enrolled patients with stage III lung cancer from the Shandong Tumor Hospital & Institute in China from January 2013 to September 2014. All patients received concurrent or sequential chemo-radiotherapy, or radiotherapy only. EGCG was administrated once ARIE appeared. EGCG was given with the concentration of 440 μmol/L during radiotherapy and additionally two weeks after radiotherapy. RTOG score, dysphagia and pain related to esophagitis were recorded every week. Results: Thirty-seven patients with stage IIIA and IIIB lung cancer were enrolled in this trial. In comparison to the original, the RTOG score in the 1st, 2nd, 3rd, 4th, 5th week after EGCG prescription and the 1st, 2nd week after radiotherapy decreased significantly (P = 0.002, 0.000, 0.000, 0.001, 0.102, 0.000, 0.000, respectively). The pain score of each week was significantly lower than the baseline (P = 0.000, 0.000, 0.000, 0.000, 0.006, 0.000, 0.000, respectively). Conclusion: This trial confirmed that the oral administration of EGCG is an effective and safe method to deal with ARIE. A phase III randomized controlled trial is expected to further corroborate the consequence of EGCG in ARIE treatment

  19. Development of a murine model of acute radiation encephalopathy

    International Nuclear Information System (INIS)

    Xing Yigang; Tang Yamei; Liu Jun; Sun Ying

    2003-01-01

    Objective: To develop a murine model of acute radiation encephalopathy. Methods: A total of 40 rats were subjected to local γ-irradiation to the brain with the dosage of 7 Gy/d for 6 consecutive days. The amount of food intake, hairs and skin of irradiated field, body weight, general activities, CNS symptoms and signs were examined and recorded after irradiation. On day 3, 7, 14 and 30, the brain tissue was removed to observe histopathologic changes. Results: During the first two days after irradiation, the irradiated rats were agitated, and the amount of food intake decreased from day 2 onwards. No serious skin reaction to irradiation was observed. Survived rats had normal activities without any abnormal nervous signs. Histopathologic changes showed slight neuronal degeneration, smaller cell body, red-colored cytoplasm, disappearance of Nissl body, vacuolation, typical cell shrinkage, chromatin condensation and nuclear divergence. On the 14th and 30th days, hypochromatism, loose and reticular necrotic foci were found in some samples. Conclusion: The murine model of acute radiation encephalopathy is useful and practical in radiobiological studies

  20. The effect of Mepitel Film on acute radiation-induced skin reactions in head and neck cancer patients: a feasibility study.

    Science.gov (United States)

    Wooding, Hayley; Yan, Jing; Yuan, Ling; Chyou, Te-Yu; Gao, Shanbao; Ward, Iain; Herst, Patries M

    2018-01-01

    Mepitel Film significantly decreases acute radiation-induced skin reactions in breast cancer patients. Here we investigated the feasibility of using Mepitel Film in head and neck cancer patients (ACTRN12614000932662). Out of a total of 36 head and neck cancer patients from New Zealand (NZ) (n = 24) and China (n = 12) recruited between June 2015 and December 2016, 33 patients complied with protocol. Of these, 11 NZ patients followed a management protocol; 11 NZ patients and 11 Chinese patients followed a prophylactic protocol. An area of the neck receiving a homogenous radiation dose of > 35 Gy was divided into two equal halves; one half was randomized to Film and the other to either Sorbolene cream (NZ) or Biafine cream (China). Skin reaction severity was measured by Radiation Induced Skin Reaction Assessment Scale and expanded Radiation Therapy Oncology Group toxicity criteria. Skin dose was measured by thermoluminescent dosimeters or gafchromic film. Film decreased overall skin reaction severity (combined Radiation Induced Skin Reaction Assessment Scale score) by 29% and moist desquamation rates by 37% in the Chinese cohort and by 27 and 28%, respectively in the NZ cohort. Mepitel Film did not affect head movements but did not adhere well to the skin, particularly in males with heavy beard stubble, and caused itchiness, particularly in Chinese patients. Mepitel Film reduced acute radiation-induced skin reactions in our head and neck cancer patients, particularly in patients without heavy stubble. Advances in knowledge: This is the first study to confirm the feasibility of using Mepitel Film in head and neck cancer patients.

  1. The efficacy of octreotide in the therapy of acute radiation-induced diarrhea: a randomized controlled study

    International Nuclear Information System (INIS)

    Yavuz, Melek N.; Yavuz, A. Aydin; Aydin, Fazil; Can, Gamze; Kavgaci, Halil

    2002-01-01

    Purpose: Although the somatostatin analog octreotide is currently used in the treatment of chemotherapy-induced diarrhea and secretory diarrhea associated with various disorders, its role in the management of radiation enteritis is not well defined. We performed a randomized study that compared octreotide acetate with diphenoxylate hydrochloride plus atropine sulfate, the drug commonly used as therapy for acute radiation-induced diarrhea (ARID). Methods and Materials: Sixty-one patients with Grade 2 (four to six stools per day) or Grade 3 (≥ seven stools per day, National Cancer Institute Common Toxicity Criteria) diarrhea associated with pelvic radiotherapy were assigned randomly to receive octreotide s.c., 100 μg three times daily (n=33) or diphenoxylate and atropine orally, 2.5 mg four times daily (n = 28). Radiotherapy was delivered to all patients in a conventional manner, with high-energy photons in a total dose ≥45 Gy, which exceeds the tolerance of intestine. Overall, there was no significant difference in patient characteristics or radiotherapy applied between the two arms. Patients were evaluated daily for the primary study end point, resolution of diarrhea, as well as for interruption of pelvic radiotherapy. Results: Within 3 days, ARID completely resolved in 20 patients in the octreotide arm (2 within the first day, 11 within the second day, and 7 within the third day) vs. only 4 (all within the second day of therapy) in the diphenoxylate arm (p=0.002). On the diphenoxylate arm, 15/28 patients were required to discontinue pelvic radiotherapy; on the octreotide arm, 6/33 patients were required to discontinue pelvic radiotherapy for an average of 1.89±0.5 and 0.45±0.2 days, respectively (p=0.003). No side effects were observed in either arm. Three patients on the diphenoxylate arm and only 1 on the octreotide arm required further treatment for parenteral replenishment of fluids and electrolytes or other antidiarrheal treatments. Conclusion

  2. Radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Ohyama, Harumi

    1995-01-01

    Apoptosis is an active process of gene-directed cellular self-destruction that can be induced in many cell types via numerous physiological and pathological stimuli. We found that interphasedeath of thymocytes is a typical apoptosis showing the characteristic features of apoptosis including cell shrinkage, chromatin condensation and DNA degradation. Moderate dose of radiation induces extensive apoptosis in rapidly proliferating cell population such as the epithelium of intestinal crypt. Recent reports indicate that the ultimate form of radiation-induced mitotic death in several cells is also apoptosis. One of the hallmarks of apoptosis is the enzymatic internucleosomal degradation of chromatin DNA. We identified an endonuclease responsible for the radiation-induced DNA degradation in rat thymocytes. The death-sparing effects of interrupting RNA and protein synthesis suggested a cell genetic program for apoptosis. Apoptosis of thymocytes initiated by DNA damage, such as radiation and radio mimetic substance, absolutely requires the protein of p53 cancer suppresser gene. The cell death induced by glucocorticoid, or aging, has no such requirement. Expression of oncogene bcl-2 rescues cells from the apoptosis. Massive apoptosis in radiosensitive cells induced by higher dose radiation may be fatal. It is suggested that selective apoptotic elimination of cells would play an important role for protection against carcinogenesis and malformation through removal of cells with unrepaired radiation-induced DNA damages. Data to evaluate the significance of apoptosis in the radiation risk are still poor. Further research should be done in order to clarify the roles of the cell death on the acute and late effects of irradiation. (author)

  3. Regulatory T Cells Contribute to the Inhibition of Radiation-Induced Acute Lung Inflammation via Bee Venom Phospholipase A₂ in Mice.

    Science.gov (United States)

    Shin, Dasom; Lee, Gihyun; Sohn, Sung-Hwa; Park, Soojin; Jung, Kyung-Hwa; Lee, Ji Min; Yang, Jieun; Cho, Jaeho; Bae, Hyunsu

    2016-04-30

    Bee venom has long been used to treat various inflammatory diseases, such as rheumatoid arthritis and multiple sclerosis. Previously, we reported that bee venom phospholipase A₂ (bvPLA₂) has an anti-inflammatory effect through the induction of regulatory T cells. Radiotherapy is a common anti-cancer method, but often causes adverse effects, such as inflammation. This study was conducted to evaluate the protective effects of bvPLA₂ in radiation-induced acute lung inflammation. Mice were focally irradiated with 75 Gy of X-rays in the lung and administered bvPLA₂ six times after radiation. To evaluate the level of inflammation, the number of immune cells, mRNA level of inflammatory cytokine, and histological changes in the lung were measured. BvPLA₂ treatment reduced the accumulation of immune cells, such as macrophages, neutrophils, lymphocytes, and eosinophils. In addition, bvPLA₂ treatment decreased inflammasome-, chemokine-, cytokine- and fibrosis-related genes' mRNA expression. The histological results also demonstrated the attenuating effect of bvPLA₂ on radiation-induced lung inflammation. Furthermore, regulatory T cell depletion abolished the therapeutic effects of bvPLA₂ in radiation-induced pneumonitis, implicating the anti-inflammatory effects of bvPLA₂ are dependent upon regulatory T cells. These results support the therapeutic potential of bvPLA₂ in radiation pneumonitis and fibrosis treatments.

  4. Comparison of the protective roles of L-carnitine and amifostine against radiation-induced acute ovarian damage by histopathological and biochemical methods

    Directory of Open Access Journals (Sweden)

    Vuslat Yurut-Caloglu

    2015-01-01

    Full Text Available Purpose: The aim of this study was to compare the radioprotective efficacies of L-carnitine (LC and amifostine against radiation-induced acute ovarian damage. Materials and Methods: Forty-five, 3-month-old Wistar albino rats were randomly assigned to six groups. Control (CONT, n = 7; irradiation alone RT: radiation therapy (RT, n = 8; amifostine plus irradiation (AMI + RT, n = 8; LC plus irradiation (LC + RT, n = 8; LC and sham irradiation (LC, n = 7; and amifostine and sham irradiation (AMI, n = 7. The rats in the AMI + RT, LC + RT and RT groups were irradiated with a single dose of 20 Gy to the whole abdomen. LC (300 mg/kg and amifostine (200 mg/kg was given intraperitoneally 30 min before irradiation. Five days after irradiation, both antral follicles and corpus luteum in the right ovaries were counted, and tissue levels of malondialdehyde (MDA and advanced oxidation protein product (AOPP were measured. Results: Irradiation significantly decreased antral follicles and corpus luteum (P: 0.005 and P 0.05. The level of MDA and AOPP significantly increased after irradiation (P = 0.001 and P 0.005. The levels of both MDA and AOPP were also similar when LC + RT is compared with AMI + RT group (P > 0.005. Conclusions: L-carnitine and amifostine have a noteworthy and similar radioprotective effect against radiation-induced acute ovarian toxicity.

  5. Correlation of the acute oxidative stress markers with radiation induced late lung disease response of pneumonitis and/or fibrosis

    International Nuclear Information System (INIS)

    Kunwar, Amit

    2016-01-01

    Biomarkers which predict for the occurrence of radiation-induced lung responses of pneumonitis and/or fibrosis are largely unknown. Herein, we investigated whether markers of oxidative stress and intracellular antioxidants, measured within days of radiation exposure, correlated with the lung tissue injury response occurring weeks later. Inbred strains of mice (KK/HIJ, C57BL/6J, 129S1/SvImJ, C3H/HeJ, A/J, AKR/J, CBA/J, NZW/LacJ) known to differ in their susceptibility to radiation induced pulmonary fibrosis, and to vary in time to onset of respiratory distress post thoracic irradiation (from 10-23 weeks) were studied. Mice were unirradiated (controls) or received whole thorax irradiation (18 Gy) and were euthanized at 6h, 1d, 7d, 8w and upon presentation of respiratory distress. Pulmonary levels of antioxidants superoxide dismutase, catalase, glutathione peroxidase (GPx) and glutathione, and of oxidative damage (reactive oxygen species (ROS), 8-hydroxydeoxyguanosine (8-OHdG) and numbers of γH2AX foci), were assessed

  6. Peritoneal macrophages mediated delivery of chitosan/siRNA nanoparticle to the lesion site in a murine radiation-induced fibrosis model

    DEFF Research Database (Denmark)

    Nawroth, Isabel; Alsner, Jan; Deleuran, B.W.

    2013-01-01

    of chitosan/siRNA nanoparticles directed towards silencing TNF alpha in local macrophage populations, but the mechanism for the therapeutic effect at the lesion site remains unclear. Methods. Using the same murine RIF model we utilized an optical imaging technique and fluorescence microscopy to investigate...... the uptake of chitosan/fluorescently labeled siRNA nanoparticles by peritoneal macrophages and their subsequent migration to the inflamed tissue in the RIF model. Results. We observed strong accumulation of the fluorescent signal in the lesion site of the irradiated leg up to 24 hours using the optical...... imaging system. We further confirm by immunohistochemical staining that Cy3 labeled siRNA resides in macrophages of the irradiated leg. Conclusion. We provide a proof-of-concept for host macrophage trafficking towards the inflamed region in a murine RIF model, which thereby suggests that the chitosan...

  7. Curcumin protects against radiation-induced acute and chronic cutaneous toxicity in mice and decreases mRNA expression of inflammatory and fibrogenic cytokines

    International Nuclear Information System (INIS)

    Okunieff, Paul; Xu Jianhua; Hu Dongping; Liu Weimin; Zhang Lurong; Morrow, Gary; Pentland, Alice; Ryan, Julie L.; Ding, Ivan M.D.

    2006-01-01

    Purpose: To determine whether curcumin ameliorates acute and chronic radiation skin toxicity and to examine the expression of inflammatory cytokines (interleukin [IL]-1, IL-6, IL-18, IL-1Ra, tumor necrosis factor [TNF]-α, and lymphotoxin-β) or fibrogenic cytokines (transforming growth factor [TGF]-β) during the same acute and chronic phases. Methods and Materials: Curcumin was given intragastrically or intraperitoneally to C3H/HeN mice either: 5 days before radiation; 5 days after radiation; or both 5 days before and 5 days after radiation. The cutaneous damage was assessed at 15-21 days (acute) and 90 days (chronic) after a single 50 Gy radiation dose was given to the hind leg. Skin and muscle tissues were collected for measurement of cytokine mRNA. Results: Curcumin, administered before or after radiation, markedly reduced acute and chronic skin toxicity in mice (p < 0.05). Additionally, curcumin significantly decreased mRNA expression of early responding cytokines (IL-1 IL-6, IL-18, TNF-α, and lymphotoxin-β) and the fibrogenic cytokine, TGF-β, in cutaneous tissues at 21 days postradiation. Conclusion: Curcumin has a protective effect on radiation-induced cutaneous damage in mice, which is characterized by a downregulation of both inflammatory and fibrogenic cytokines in irradiated skin and muscle, particularly in the early phase after radiation. These results may provide the molecular basis for the application of curcumin in clinical radiation therapy

  8. Association of TGF-β1 and XPD polymorphisms with severe acute radiation-induced esophageal toxicity in locally advanced lung cancer patients treated with radiotherapy

    International Nuclear Information System (INIS)

    Zhang Li; Yang Ming; Bi Nan; Ji Wei; Wu Chen; Tan Wen; Zhao Lujun; Yu Dianke; Lin Dongxin; Wang Luhua

    2010-01-01

    Purpose: Radiation-induced esophageal toxicity (RIET) is a dose-limiting toxicity in lung cancer patients receiving radiotherapy. Accumulating evidence indicates that DNA repair and the cytokine pathways play essential roles in radiation-induced diseases. Genetic polymorphisms of genes in these pathways may affect gene function and/or gene expression and lead to different treatment-related esophageal toxicity. Materials and methods: This study investigated the association of 21 polymorphisms in 14 genes, with the occurrence of ≥grade 2 acute RIET. Genotypes were analyzed among 213 stage III lung cancer patients receiving radiotherapy. Results: We used Cox proportional hazard model to examine the effects of genotypes on ≥grade 2 acute RIET risk and Kaplan-Meier estimator to compare effects of different genotypes on such risk. Multivariate analysis showed that CT or TT genotype of TGF-β1-509C/T polymorphism was associated with a significantly higher RIET risk (adjusted hazard ratio [HR] = 2.47; 95% confidence interval (CI) = 1.17-5.24; P = 0.018, or HR = 3.86; 95% CI = 1.50-9.92; P = 0.005), respectively, compared with the CC genotype. Moreover, Lys/Gln+Gln/Gln genotypes of XPD Lys751Gln polymorphism were also associated with a significantly decreased RIET risk (adjusted HR = 0.55; 95% CI = 0.32-0.96; P = 0.030). Conclusions: This report, for the first time, examined the influence of inherited variation in the DNA repair and the cytokine pathways on RIET.

  9. A phase II randomized study of topical intrarectal administration of amifostine for the prevention of acute radiation-induced rectal toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Kouloulias, V.E. [Dept. of Radiation Oncology, Aretaieion Univ. Hospital, Univ. of Athens Medical School, Athens (Greece); Dept. of Electrical and Computer Engineering, National Technical Univ. of Athens, Athens (Greece); Center of Radiation Oncology, YGEIA Diagnostic and Therapeutic Center of Athens, Athens (Greece); Kouvaris, J.R.; Kokakis, J.D.; Antypas, C.; Mallas, E.; Vosdoganis, S.P.; Vlahos, L.J. [Dept. of Radiation Oncology, Aretaieion Univ. Hospital, Univ. of Athens Medical School, Athens (Greece); Pissakas, G. [Radiotherapy Dept., Agios Savvas Anticancer Hospital, Athens (Greece); Matsopoulos, G. [Dept. of Electrical and Computer Engineering, National Technical Univ. of Athens, Athens (Greece); Michopoulos, S. [Gastroenterology Unit, Alexandra General Hospital, Athens (Greece); Kostakopoulos, A. [Urology Dept., Sismanoglio Hospital, Univ. of Athens Medical School, Athens (Greece)

    2004-09-01

    Purpose: to investigate the cytoprotective effect of intrarectal amifostine administration on acute radiation-induced rectal toxicity. Patients and methods: 67 patients with T1b-2 NO MO prostate cancer were randomized to receive amifostine intrarectally (group A, n - 33) or not (group B, n = 34) before irradiation. Therapy was delivered using a four-field technique with three-dimensional conformal planning. In group A, 1,500 mg amifostine was administered intrarectally as an aqueous solution in a 40-ml enema. Two different toxicity scales were used: EORTC/RTOG rectal and urologic toxicity criteria along with a Subjective-RectoSigmoid (S-RS) scale based on the endoscopic terminology of the World Organization for Digestive Endoscopy. Objective measurements with rectosigmoidoscopy were performed at baseline and 1-2 days after the completion of radiotherapy. The area under curve for the time course of mucositis (RTOG criteria) during irradiation represented the mucositis index (MI). Results: intrarectal amifostine was feasible and well tolerated without any systemic or local side effects. According to the RTOG toxicity scale, five out of 33 patients showed grade 1 mucositis in group A versus 15 out of 34 patients with grade 1/2 in group B (p = 0.026). Mean rectal MI was 0.3 {+-} 0.1 in group A versus 2.2 {+-} 0.4 in group B (p < 0.001), while S-RS score was 3.9 {+-} 0.5 in group A versus 6.3 {+-} 0.7 in group B (p < 0.001). The incidence of urinary toxicity was the same in both groups. Conclusion: intrarectal administration of amifostine seems to have a cytoprotective efficacy in acute radiation-induced rectal mucositis. Further randomized studies are needed for definitive therapeutic decisions. (orig.)

  10. 8-prenylnaringenin and tamoxifen inhibit the shedding of irradiated epithelial cells and increase the latency period of radiation-induced oral mucositis. Cell culture and murine model

    Energy Technology Data Exchange (ETDEWEB)

    Ryck, Tine de; Impe, Annouchka van; Bracke, Marc E. [Ghent University, Laboratory of Experimental Cancer Research, Department Radiation Oncology and Experimental Cancer Research, Ghent (Belgium); Vanhoecke, Barbara W. [Ghent University, Laboratory of Experimental Cancer Research, Department Radiation Oncology and Experimental Cancer Research, Ghent (Belgium); Ghent University, Laboratory of Microbial Ecology and Technology (LabMET), Ghent (Belgium); Heyerick, Arne [Ghent University, Laboratory of Pharmacognosy and Phytochemistry, Ghent (Belgium); Vakaet, Luc; Neve, Wilfried de [Ghent University Hospital, Department of Radiation Oncology, Ghent (Belgium); Mueller, Doreen [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, Department of Radiotherapy and Radiation Oncology, OncoRay-National Center for Radiation Research in Oncology, Dresden (Germany); Schmidt, Margret [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, Department of Radiotherapy and Radiation Oncology, OncoRay-National Center for Radiation Research in Oncology, Dresden (Germany); German Cancer Consortium (DKTK) partner site Dresden and German Cancer Center (DKFZ), Heidelberg (Germany); Doerr, Wolfgang [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, Department of Radiotherapy and Radiation Oncology, OncoRay-National Center for Radiation Research in Oncology, Dresden (Germany); Medical University, Department of Radiation Oncology, CCC, and CD-Laboratory RadOnc, Vienna (Austria)

    2015-05-01

    The major component in the pathogenesis of oral radiation-induced mucositis is progressive epithelial hypoplasia and eventual ulceration. Irradiation inhibits cell proliferation, while cell loss at the surface continues. We conceived to slow down this desquamation by increasing intercellular adhesion, regulated by the E-cadherin/catenin complex. We investigated if 8-prenylnaringenin (8-PN) or tamoxifen (TAM) decrease the shedding of irradiated human buccal epithelial cells in vitro and thus delay the ulcerative phase of radiation-induced mucositis in vivo. In vitro, aggregates of buccal epithelial cells were irradiated and cultured in suspension for 11 days. 8-PN or TAM were investigated regarding their effect on cell shedding. In vivo, the lower tongue surface of mice was irradiated with graded single doses of 25 kV X-rays. The incidence, latency, and duration of the resulting mucosal ulcerations were analyzed after topical treatment with 8-PN, TAM or solvent. 8-PN or TAM prevented the volume reduction of the irradiated cell aggregates during the incubation period. This was the result of a higher residual cell number in the treated versus the untreated irradiated aggregates. In vivo, topical treatment with 8-PN or TAM significantly increased the latency of mucositis from 10.9 to 12.1 and 12.4 days respectively, while the ulcer incidence was unchanged. 8-PN and TAM prevent volume reduction of irradiated cell aggregates in suspension culture. In the tongues of mice, these compounds increase the latency period. This suggests a role for these compounds for the amelioration of radiation-induced mucositis in the treatment of head and neck tumors. (orig.) [German] Die wesentliche Komponente in der Pathogenese der radiogenen Mukositis ist eine progressive epitheliale Hypoplasie und letztendlich Ulzeration. Die Bestrahlung hemmt die Zellproliferation, waehrend der Zellverlust an der Oberflaeche fortbesteht. Wir versuchten, diese Desquamation durch eine Stimulation der

  11. 1,2,3,4,6-penta-ο-galloyl-β-D-glucose protects splenocytes against radiation-induced apoptosis in murine splenocytes

    International Nuclear Information System (INIS)

    Bing, So-Jin; Kim, Min-Ju; Park, Eunjin

    2010-01-01

    Antioxidant property and hematopoietic repair capacity are important characteristics of radioprotective agents. Some studies have demonstrated that 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), a molecule isolated from the waterlily, has antioxidant, hematopoietic repair, and anti-inflammatory activities. In this study, we try to determine whether PGG extracted from a lily, Nymphaea tetragona var. angusta, has radioprotective effects on splenocytes in vitro against 60 Co γ-ray irradiation with absorption doses of 2 Gy and 4 Gy. Results show that PGG treatment dramatically enhances the proliferation of splenocytes compared with irradiated but untreated controls. In addition, PGG treatment before irradiation protects the splenocytes from lethal effects of irradiation and decreases DNA damages as identified by the alkaline comet assay. PGG-treated cells also show less radiation-induced apoptosis. These cells have lower concentrations of the pro-apoptotic protein p53 and more of the antiapoptotic protein Bcl-2. The results presented in this study suggest that PGG has a cytoprotective effect on immune cells exposed to normally damaging amount of radiation. Thus, PGG could be an effective, non-toxic radioprotective agent. (author)

  12. Acute lethal toxicity following passive immunization for treatment of murine cryptococcosis.

    OpenAIRE

    Savoy, A C; Lupan, D M; Manalo, P B; Roberts, J S; Schlageter, A M; Weinhold, L C; Kozel, T R

    1997-01-01

    Passive immunization with monoclonal antibodies (MAbs) specific for the major capsular polysaccharide of Cryptococcus neoformans alters the course of murine cryptococcosis. During studies of passive immunization for treatment of murine cryptococcosis, we noted the occurrence of an acute, lethal toxicity. Toxicity was characterized by scratching, lethargy, respiratory distress, collapse, and death within 20 to 60 min after injection of antibody. The toxic effect was observed only in mice with ...

  13. Comparison of Radiation-Induced Bystander Effect in QU-DB Cells after Acute and Fractionated Irradiation: An In Vitro Study.

    Science.gov (United States)

    Soleymanifard, Shokouhozaman; Bahreyni Toossi, Mohammad Taghi; Kamran Samani, Roghayeh; Mohebbi, Shokoufeh

    2016-01-01

    Radiation effects induced in non-irradiated cells are termed radiation-induced bystander effects (RIBE). The present study intends to examine the RIBE response of QU-DB bystander cells to first, second and third radiation fractions and compare their cumulative outcome with an equal, single acute dose. This experimental study irradiated three groups of target cells for one, two and three times with(60)Co gamma rays. One hour after irradiation, we transferred their culture media to non-irradiated (bystander) cells. We used the cytokinesis block micronucleus assay to evaluate RIBE response in the bystander cells. The numbers of micronuclei generated in bystander cells were determined. RIBE response to single acute doses increased up to 4 Gy, then decreased, and finally at the 8 Gy dose disappeared. The second and third fractions induced RIBE in bystander cells, except when RIBE reached to the maximum level at the first fraction. We split the 4 Gy acute dose into two fractions, which decreased the RIBE response. However, fractionation of 6 Gy (into two fractions of 3 Gy or three fractions of 2 Gy) had no effect on RIBE response. When we split the 8 Gy acute dose into two fractions we observed RIBE, which had disappeared following the single 8 Gy dose. The impact of dose fractionation on RIBE induced in QU-DB cells de- pended on the RIBE dose-response relationship. Where RIBE increased proportion- ally with the dose, fractionation reduced the RIBE response. In contrast, at high dos- es where RIBE decreased proportionally with the dose, fractionation either did not change RIBE (at 6 Gy) or increased it (at 8 Gy).

  14. Acute Febrile Illness and Complications Due to Murine Typhus, Texas, USA1,2.

    Science.gov (United States)

    Afzal, Zeeshan; Kallumadanda, Sunand; Wang, Feng; Hemmige, Vagish; Musher, Daniel

    2017-08-01

    Murine typhus occurs relatively commonly in southern Texas, as well as in California. We reviewed records of 90 adults and children in whom murine typhus was diagnosed during a 3-year period in 2 hospitals in southern Texas, USA. Most patients lacked notable comorbidities; all were immunocompetent. Initial signs and symptoms included fever (99%), malaise (82%), headache (77%), fatigue (70%), myalgias (68%), and rash (39%). Complications, often severe, in 28% of patients included bronchiolitis, pneumonia, meningitis, septic shock, cholecystitis, pancreatitis, myositis, and rhabdomyolysis; the last 3 are previously unreported in murine typhus. Low serum albumin and elevated procalcitonin, consistent with bacterial sepsis, were observed in >70% of cases. Rash was more common in children; thrombocytopenia, hyponatremia, elevated hepatic transaminases, and complications were more frequent in adults. Murine typhus should be considered as a diagnostic possibility in cases of acute febrile illness in southern and even in more northern US states.

  15. Role of Vitamin C As A Potent Antioxidant in Acute Radiation Induced Liver Disease (RILD) Among Male Albino Rats

    International Nuclear Information System (INIS)

    Ezz El Arab, A.; Ayad, S.K.Y.; El Fouly, A.

    2012-01-01

    Recent studies demonstrated the role of vitamin C as antioxidant in alleviating organ damage caused by gamma irradiation. The present study was conducted to find out the effect of vitamin C on liver biochemical functions such as serum ALT, AST, albumin and bilirubin after experimental liver damage induced by gamma irradiation. Rats irradiated with gamma radiation were used as a model of liver injury terminating with necro inflammatory activity and acute hepatitis. Forty male albino rats were classified into 6 groups (G0-G5). G0 included 8 male albino rats that were divided to 2 subgroups (4 rats/subgroup). Both subgroups were exposed to gamma irradiation with 6 Gy as a single dose. The first subgroup was left for 3 weeks then serum and liver samples were collected while in the second subgroup, 2 rats were died and the remaining 2 rats were left for 6 weeks then serum and liver samples were collected. G1 was the negative control while in the rest groups, the whole body of rats was exposed to gamma irradiation of dose 8 Gy divided to 2 doses (4 Gy/one dose) at one week interval in between. G2 included 12 albino rats divided into 3 subgroups (4 rats/subgroup). The whole body of albino rats of G2 was exposed to 8 Gy gamma irradiation that divided as mentioned before. Serum and liver samples were collected after one day, two days and four days after last dose of irradiation. G3 also included 8 rats that were divided into 2 subgroups (4 rats/subgroup) and whole body was exposed to 8 Gy gamma irradiation that were divided as mentioned before. Serum and liver samples were collected after one week for one subgroup and 2 weeks for other subgroup after last dose of irradiation. The rest 2 groups (4 rats/group) were exposed to 8Gy gamma irradiation divided as before, but the rats in one group were orally supplemented with low dose of vitamin C. G4 and the others were supplemented with high dose of vitamin C for 2 weeks starting after last dose of irradiation (G5) then serum

  16. Effect of MgSO4 on the contents of Ca2+ in brain cell and NO in brain tissue of rats with radiation-induced acute brain injury

    International Nuclear Information System (INIS)

    Yuan Wenjia; Cui Fengmei; Liu Ping; He Chao; Tu Yu; Wang Lili

    2009-01-01

    The work is to explore the protection of magnesium sulfate(MgSO 4 ) on radiation-induced acute brain injury. Thirty six mature Sprague-Dawley(SD) rats were randomly divided into 3 groups of control, experimental control and experimental therapy group. The whole brains of SD rats of experimental control and experimental therapy group were irradiated with a dose of 20 Gy using 6 MeV electron beam. MgSO 4 was injected into the abdomen of experimental therapy rats group 1 day before, immediately and continue for 5 days after irradiation respectively. The brain tissues were taken on 3, 10, 17 and 24 d after irradiation. Ca 2+ content in brain cell was measured by laser scanning confocal microscopy, and the NO content in brain tissue was detected by the method of nitric acid reductase. Compared with the blank control group, the contents of Ca 2+ in brain cell and NO in brain tissue of the experimental control group increase (P 4 used in early stage can inhibit the contents of Ca 2+ in brain cell and NO in brain tissue after radiation-induced acute brain injury. It means that MgSO 4 has a protective effect on radiation-induced acute brain injury. (authors)

  17. TU-G-BRA-08: BEST IN PHYSICS (JOINT IMAGING-THERAPY): Hybrid PET-MRI Imaging of Acute Radiation Induced Cardiac Toxicity

    International Nuclear Information System (INIS)

    El-Sherif, O; Xhaferllari, I; Gaede, S; Sykes, J; Butler, J; Wisenberg, G; Prato, F

    2015-01-01

    Purpose: To identify the presence of low-dose radiation induced cardiac toxicity in a canine model using hybrid positron emission tomography (PET) and magnetic resonance imaging (MRI). Methods: Research ethics board approval was obtained for a longitudinal imaging study of 5 canines after cardiac irradiation. Animals were imaged at baseline, 1 week post cardiac irradiation, and 1 month post cardiac irradiation using a hybrid PET- MRI system (Biograph mMR, Siemens Healthcare). The imaging protocol was designed to assess acute changes in myocardial perfusion and inflammation. Myocardial perfusion imaging was performed using N13-ammonia tracer followed by a dynamic PET acquisition scan. A compartmental tracer kinetic model was used for absolute perfusion quantification. Myocardial inflammation imaging was performed using F18-fluorodeoxyglucose (FDG) tracer. The standard uptake value (SUV) over a region encompassing the whole heart was used to compare FDG scans. All animals received a simulation CT scan (GE Medical Systems) for radiation treatment planning. Radiation treatment plans were created using the Pinncale3 treatment planning system (Philips Radiation Oncology Systems) and designed to resemble the typical cardiac exposure during left-sided breast cancer radiotherapy. Cardiac irradiations were performed in a single fraction using a TrueBeam linear accelerator (Varian Medical Systems). Results: The delivered dose (mean ± standard deviation) to heart was 1.8±0.2 Gy. Reductions in myocardial stress perfusion relative to baseline were observed in 2 of the 5 animals 1 month post radiation. A global inflammatory response 1 month post radiation was observed in 4 of the 5 animals. The calculated SUV at 1 month post radiation was significantly higher (p=0.05) than the baseline SUV. Conclusion: Low doses of cardiac irradiation (< 2 Gy) may lead to myocardial perfusion defects and a global inflammatory response that can be detectable as early as 1 month post irradiation

  18. Application of 1H NMR spectroscopy-based metabonomics to feces of cervical cancer patients with radiation-induced acute intestinal symptoms.

    Science.gov (United States)

    Chai, Yanlan; Wang, Juan; Wang, Tao; Yang, Yunyi; Su, Jin; Shi, Fan; Wang, Jiquan; Zhou, Xi; He, Bin; Ma, Hailin; Liu, Zi

    2015-11-01

    Radiation-induced acute intestinal symptoms (RIAISs) are a common complication of radiotherapy for cervical cancer. The aim of this study was to use (1)H nuclear magnetic resonance ((1)H NMR) combined with chemometric analysis to develop a metabolic profile of patients with RIAISs. Fecal samples were collected from 66 patients with cervical cancer before and after pelvic radiotherapy. After radiotherapy, RIAISs occurred in eleven patients. We selected another 11 patients from participants without RIAISs whose age, stage, histological type and treatment methods are matched with RIAIS patients as the control group. (1)H NMR spectroscopy combined with multivariate pattern recognition analysis was used to generate metabolic profile data, as well as to establish a RIAIS-specific metabolic phenotype. Orthogonal partial least-squares discriminant analysis was used to distinguish samples between the pre- and post-radiotherapy RIAIS patients and between RIAIS patients and controls. Fecal samples from RIAIS patients after pelvic radiotherapy were characterized by increased concentrations of α-ketobutyrate, valine, uracil, tyrosine, trimethylamine N-oxide, phenylalanine, lysine, isoleucine, glutamine, creatinine, creatine, bile acids, aminohippurate, and alanine, accompanied by reduced concentrations of α-glucose, n-butyrate, methylamine, and ethanol relative to samples from RIAIS patients before pelvic radiotherapy, while in RIAIS patients relative to controls, trimethylamine, n-butyrate, fumarate and acetate were down-regulated and valine, TMAO, taurine, phenylalanine, lactate, isoleucine and creatinine were up-regulated. We obtained the metabolic profile of RIAIS patients from fecal samples using NMR-based metabonomics. This profile has the potential to be developed into a novel clinical tool for RIAIS diagnosis or therapeutic monitoring, and could contribute to an improved understanding of the disease mechanism. However, because of the limitations of methods, technique

  19. TU-G-BRA-08: BEST IN PHYSICS (JOINT IMAGING-THERAPY): Hybrid PET-MRI Imaging of Acute Radiation Induced Cardiac Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    El-Sherif, O; Xhaferllari, I; Gaede, S [Western Univeristy, London, ON (United Kingdom); London Regional Cancer Program, London, ON (United Kingdom); Sykes, J; Butler, J [Lawson Health Research Institute, London, ON (United Kingdom); Wisenberg, G; Prato, F [Western Univeristy, London, ON (United Kingdom); Lawson Health Research Institute, London, ON (United Kingdom)

    2015-06-15

    Purpose: To identify the presence of low-dose radiation induced cardiac toxicity in a canine model using hybrid positron emission tomography (PET) and magnetic resonance imaging (MRI). Methods: Research ethics board approval was obtained for a longitudinal imaging study of 5 canines after cardiac irradiation. Animals were imaged at baseline, 1 week post cardiac irradiation, and 1 month post cardiac irradiation using a hybrid PET- MRI system (Biograph mMR, Siemens Healthcare). The imaging protocol was designed to assess acute changes in myocardial perfusion and inflammation. Myocardial perfusion imaging was performed using N13-ammonia tracer followed by a dynamic PET acquisition scan. A compartmental tracer kinetic model was used for absolute perfusion quantification. Myocardial inflammation imaging was performed using F18-fluorodeoxyglucose (FDG) tracer. The standard uptake value (SUV) over a region encompassing the whole heart was used to compare FDG scans. All animals received a simulation CT scan (GE Medical Systems) for radiation treatment planning. Radiation treatment plans were created using the Pinncale3 treatment planning system (Philips Radiation Oncology Systems) and designed to resemble the typical cardiac exposure during left-sided breast cancer radiotherapy. Cardiac irradiations were performed in a single fraction using a TrueBeam linear accelerator (Varian Medical Systems). Results: The delivered dose (mean ± standard deviation) to heart was 1.8±0.2 Gy. Reductions in myocardial stress perfusion relative to baseline were observed in 2 of the 5 animals 1 month post radiation. A global inflammatory response 1 month post radiation was observed in 4 of the 5 animals. The calculated SUV at 1 month post radiation was significantly higher (p=0.05) than the baseline SUV. Conclusion: Low doses of cardiac irradiation (< 2 Gy) may lead to myocardial perfusion defects and a global inflammatory response that can be detectable as early as 1 month post irradiation

  20. Dosimetry analysis on radiation-induced acute esophagitis after three-dimensional conformal radiotherapy for non-small cell lung cancer

    International Nuclear Information System (INIS)

    ZZhu Shuchai; Cui Yanli; Li Juan; Liu Zhikun; Shen Wenbin; Su Jingwei; Wang Yuxiang

    2010-01-01

    Objective: To analyze the related factors with radiation-induced esophagitis after threedimensional conformal radiotherapy for non-small cell lung cancer (NSCLC), in order to explore the predictors for optimizing the treatment planning of NSCLC. Methods: From Aug 2000 to Dec 2004, 104 NSCLC patients received radiotherapy and were eligible for this study, 45 cases squamous cell carcinoma, 20 cases adenocarcinoma, 33 cases carrying with cancer cells by test and 6 case with no definitive pathologic feature.46 patients were treated with three dimensional conformal radiotherapy (3DCRT), the other 58 patients conventional radiotherapy (CRT) before later-course 3DCRT. All the patients received the prescribed dose between 60-78 Gy and the median dose 66 Gy. The correlation of the variables were evaluated by Spearman relationship analysis. The morbidity of radiation-induced esophagitis was analyzed by X 2 test. The multivariate effect on radiation-induced esophagitis was statistically processed by Logistic regression model. Results: In 104 patients, the morbidity of radiation- induced esophagitis was 46.2%, including 32 cases at grade 1, 15 cases at grade 2, 1 case at grade 3. Univariate analysis showed the maximal and mean dose of esophagus, the volume of esophagus irradiated, the values of V 40 , V 45 , V 50 , V 55 , V 60 , LETT 45 , LETT 50 , LETT 55 , LETT 60 for the esophagus were correlated with radiation-induced esophagitis. Logistic regression model showed that the maximum dose received by the esophagus was the independent factor of ≥ 2 grade radiation-induced esophagitis. Conclusions: The maxmal dose of esophagus received might be the important factor of radiation-induced esophagitis. (authors)

  1. Radiation-induced pneumothorax

    International Nuclear Information System (INIS)

    Epstein, D.M.; Littman, P.; Gefter, W.B.; Miller, W.T.; Raney, R.B. Jr.

    1983-01-01

    Pneumothorax is an uncommon complication of radiation therapy to the chest. The proposed pathogenesis is radiation-induced fibrosis promoting subpleural bleb formation that ruptures resulting in pneumothorax. We report on two young patients with primary sarcomas without pulmonary metastases who developed spontaneous pneumothorax after irradiation. Neither patient had antecedent radiographic evidence of pulmonary fibrosis

  2. Prevention of acute radiation-induced proctosigmoiditis by balsalazide: A randomized, double-blind, placebo controlled trial in prostate cancer patients

    International Nuclear Information System (INIS)

    Jahraus, Christopher D.; Bettenhausen, Doug Phar; Malik, Uzma M.B.B.S.; Sellitti, Marguerite; St Clair, William H.

    2005-01-01

    Purpose: A common complication of pelvic radiotherapy (RT) is acute radiation-induced proctosigmoiditis (RIPS), for which a multitude of therapies have been tried. The 5-aminosalicylates (5-ASA), which are traditionally used to treat inflammatory bowel disease, have been tested; however, all but one prior randomized attempt to limit or prevent RIPS with 5-ASA-type agents have failed. We sought to evaluate balsalazide, a new 5-ASA drug, for its potential to prevent or limit RIPS in patients undergoing RT for carcinoma of the prostate, as a representative sample of pelvic RT patients. Balsalazide has a unique delivery system in that 99% of ingested drug is delivered to and activated in the colon, a higher yield than all other oral agents currently available in this class. Furthermore, it lacks the antigenic sulfa moiety present in sulfasalazine, the only other 5-ASA with demonstrated benefit in this setting. Thus, it was deemed an ideal candidate for preventing or limiting RIPS. Methods and Materials: Eligible patients included prostate cancer patients, American Joint Committee on Cancer Stage T1-3, M0 being treated with external beam radiotherapy in University of Kentucky Department of Radiation Medicine. Between January 1, 2003 and July 1, 2004, 27 eligible patients were enrolled in the study. Patients were administered 2250 mg of balsalazide or an identical-appearing placebo twice daily beginning 5 days before RT and continuing for 2 weeks after completion. Toxicities were graded weekly according to National Cancer Institute Common Toxicity Criteria v. 2.0 for each of the following: proctitis, diarrhea, dysuria, weight loss, fatigue, nausea, and vomiting. A symptom index was formulated for each toxicity consisting of the toxicity's numeric grade multiplied by the number of days it was experienced, and summed for each grade experienced throughout the course of RT. Results: With the exception of nausea or vomiting, seen in 3 patients on balsalazide and 2 on placebo

  3. Effect of a prostaglandin - given rectally for prevention of radiation-induced acute proctitis - on late rectal toxicity. Results of phase III randomized, placebo-controlled, double-blind study

    International Nuclear Information System (INIS)

    Kertesz, Tereza; Herrmann, Markus K.A.; Christiansen, Hans; Hermann, Robert M.; Hess, Clemens F.; Hille, Andrea; Zapf, Antonia; Pradier, Olivier; Schmidberger, Heinz

    2009-01-01

    Background and purpose: to assess the late effect of a prostaglandin, given rectally during irradiation, on late rectal toxicity. In the acute treatment setting no significant differences in reducing the incidence of acute proctitis symptoms in patients receiving misoprostol, however, significantly more rectal bleeding had been reported. Patients and methods: a total of 100 patients who had undergone radiotherapy for prostate cancer had been entered into this phase III randomized, placebo-controlled, double-blind study with misoprostol or placebo suppositories. The toxicity was evaluated yearly after cessation of irradiation by the RTOG/LENT-SOMA scale. Results: the median follow-up was 50 months. 20 patients suffered from grade 1, four patients from grade 2 as well, and three patients only from grade 2 toxicity. Frequency, bleeding and urgency were the most commonly reported symptoms. In keeping with other studies and clinical experience, the symptoms peaked within the first 2 years with a median for grade 1 of 13 months and for grade 2 of 15 months. The presence of acute toxicity grade 2 showed a correlation with the development of any late toxicity (p = 0.03). Any acute rectal bleeding was significant correlated with any late rectal bleeding (p = 0.017). Conclusion: misoprostol given as once-daily suppository for prevention of acute radiation-induced proctitis does neither influence the incidence and severity of radiation-induced acute nor late rectal toxicity. Misoprostol has no negative impact on the incidence and severity of late rectal bleeding, in contrast to acute rectal bleeding. The routine clinical use of misoprostol suppositories cannot be recommended. (orig.)

  4. Effect of a prostaglandin - given rectally for prevention of radiation-induced acute proctitis - on late rectal toxicity. Results of phase III randomized, placebo-controlled, double-blind study

    Energy Technology Data Exchange (ETDEWEB)

    Kertesz, Tereza; Herrmann, Markus K.A.; Christiansen, Hans; Hermann, Robert M.; Hess, Clemens F.; Hille, Andrea [Dept. of Radiotherapy and Radiooncology, Univ. of Goettingen (Germany); Zapf, Antonia [Dept. of Medical Statistics, Univ. of Goettingen (Germany); Pradier, Olivier [Dept. of Radiotherapy and Radiooncology, Univ. of Brest (France); Schmidberger, Heinz [Dept. of Radiotherapy and Radiooncology, Univ. of Mainz (Germany)

    2009-09-15

    Background and purpose: to assess the late effect of a prostaglandin, given rectally during irradiation, on late rectal toxicity. In the acute treatment setting no significant differences in reducing the incidence of acute proctitis symptoms in patients receiving misoprostol, however, significantly more rectal bleeding had been reported. Patients and methods: a total of 100 patients who had undergone radiotherapy for prostate cancer had been entered into this phase III randomized, placebo-controlled, double-blind study with misoprostol or placebo suppositories. The toxicity was evaluated yearly after cessation of irradiation by the RTOG/LENT-SOMA scale. Results: the median follow-up was 50 months. 20 patients suffered from grade 1, four patients from grade 2 as well, and three patients only from grade 2 toxicity. Frequency, bleeding and urgency were the most commonly reported symptoms. In keeping with other studies and clinical experience, the symptoms peaked within the first 2 years with a median for grade 1 of 13 months and for grade 2 of 15 months. The presence of acute toxicity grade 2 showed a correlation with the development of any late toxicity (p = 0.03). Any acute rectal bleeding was significant correlated with any late rectal bleeding (p = 0.017). Conclusion: misoprostol given as once-daily suppository for prevention of acute radiation-induced proctitis does neither influence the incidence and severity of radiation-induced acute nor late rectal toxicity. Misoprostol has no negative impact on the incidence and severity of late rectal bleeding, in contrast to acute rectal bleeding. The routine clinical use of misoprostol suppositories cannot be recommended. (orig.)

  5. Radiation-induced myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Gaenshirt, H [Heidelberg Univ. (F.R. Germany). Neurologische Klinik

    1975-10-01

    12 cases of radiation-induced myelopathy after /sup 60/Co teletherapy are reported on. Among these were 10 thoracal lesions, one cerviothoracal lesion, and one lesion of the medulla oblongata. In 9 cases, Hodgkin's disease had been the primary disease, tow patients had been irradiated because of suspected vertebral metastases of cancer of the breast, and one patient had suffered from a glomus tumour of the petrous bone. The spinal doses had exceeded the tolerance doses recommended in the relevant literature. There was no close correlation between the radiation dose and the course of the disease. The latency periods between the end of the radiotherapy and the onset of the neurological symptons varied from 6 to 16 mouths and were very constant in 7 cases with 6 to 9 months. The segmental height of the lesion corresponded to the level of irradiation. The presenting symptons of radiation-induced myelopathy are buruing dysaesthesias and Brown-Sequard's paralysis which may develop into transverse lesion of the cord with paraplegia still accompanied by dissociated perception disorders. The disease developed intermittently. Disturbances of the bladder function are frequent. The fluid is normal in most cases. Myelographic examinations were made in 8 cases. 3 cases developed into stationary cases exhibiting. Brown-Sequard syndrome, while 9 patients developed transverse lesion of the cord with paraplegia. 3 patients have died; antopsy findings are given for two of these. In the pathogenesis of radiation-induced myelopathy, the vascular factor is assumed to be of decisive importance.

  6. Radiation-induced brain injury: A review

    Directory of Open Access Journals (Sweden)

    Michael eRobbins

    2012-07-01

    Full Text Available Approximately 100,000 primary and metastatic brain tumor patients/year in the US survive long enough (> 6 months to experience radiation-induced brain injury. Prior to 1970, the human brain was thought to be highly radioresistant; the acute CNS syndrome occurs after single doses > 30 Gy; white matter necrosis occurs at fractionated doses > 60 Gy. Although white matter necrosis is uncommon with modern techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become important, because they have profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenesis of radiation-induced cognitive impairment. Given its central role in memory and neurogenesis, the majority of these studies have focused on the hippocampus. Irradiating pediatric and young adult rodent brains leads to several hippocampal changes including neuroinflammation and a marked reduction in neurogenesis. These data have been interpreted to suggest that shielding the hippocampus will prevent clinical radiation-induced cognitive impairment. However, this interpretation may be overly simplistic. Studies using older rodents, that more closely match the adult human brain tumor population, indicate that, unlike pediatric and young adult rats, older rats fail to show a radiation-induced decrease in neurogenesis or a loss of mature neurons. Nevertheless, older rats still exhibit cognitive impairment. This occurs in the absence of demyelination and/or white matter necrosis similar to what is observed clinically, suggesting that more subtle molecular, cellular and/or microanatomic modifications are involved in this radiation-induced brain injury. Given that radiation-induced cognitive impairment likely reflects damage to both hippocampal- and non-hippocampal-dependent domains, there is a critical need to investigate the microanatomic and functional effects of radiation in various brain

  7. Can short-term administration of dexamethasone abrogate radiation-induced acute cytokine gene response in lung and modify subsequent molecular responses?

    International Nuclear Information System (INIS)

    Hong, J.-H.; Chiang, C.-S.; Tsao, C.-Y.; Lin, P.-Y.; Wu, C.-J.; McBride, William H.

    2001-01-01

    Purpose: To investigate the effects of short-term administration of dexamethasone (DEX) on radiation-induced responses in the mouse lung, focusing on expression of pro-inflammatory cytokine and related genes. Methods and Materials: At indicated times after thoracic irradiation and/or drug treatment, mRNA expression levels of cytokines (mTNF-α, mIL-1α, mIL-1β, mIL-2, mIL-3, mIL-4, mIL-5, mIL-6, mIFN-γ) and related genes in the lungs of C3H/HeN mice were measured by RNase protection assay. Results: Radiation-induced pro-inflammatory cytokine mRNA expression levels in lung peak at 6 h after thoracic irradiation. DEX (5 mg/kg) suppresses both basal cytokine mRNA levels and this early response when given immediately after irradiation. However, by 24 h, in mice treated with DEX alone or DEX plus radiation, there was a strong rebound effect that lasted up to 3 days. Modification of the early radiation-induced response by DEX did not change the second wave of cytokine gene expression in the lung that occurs at 1 to 2 weeks, suggesting that early cytokine gene induction might not determine subsequent molecular events. A single dose of DEX attenuated, but did not completely suppress, increases in cytokine mRNA levels induced by lipopolysaccharide (2.5 mg/kg) treatment, but, unlike with radiation, no significant rebound effect was seen. Five days of dexamethasone treatment in the pneumonitic phase also inhibited pro-inflammatory cytokine gene expression and, again, there was a rebound effect after withdrawal of the drug. Conclusions: Our findings suggest that short-term use of dexamethasone can temporarily suppress radiation-induced pro-inflammatory cytokine gene expression, but there may be a rebound after drug withdrawal and the drug does little to change the essence and course of the pneumonitic process

  8. Radiation-induced cancer

    International Nuclear Information System (INIS)

    Dutrillaux, B.; CEA Fontenay-aux-Roses, 92

    1998-01-01

    The induction of malignant diseases is one of the most concerning late effects of ionising radiation. A large amount of information has been collected form atomic bomb survivors, patients after therapeutic irradiation, occupational follow-up and accidentally exposed populations. Major uncertainties persist in the (very) low range i.e, population and workers radioprotection. A review of the biological mechanisms leading to cancer strongly suggests that the vast majority of radiation-induced malignancies arise as a consequence of recessive mutations can be unveiled by ageing, this process being possibly furthered by constitutional or acquired genomic instability. The individual risk is likely to be very low, probably because of the usual dose level. However, the magnitude of medical exposure and the reliance of our societies on nuclear industry are so high that irreproachable decision-making processes and standards for practice are inescapable. (author)

  9. Radiation induced oral mucositis

    Directory of Open Access Journals (Sweden)

    P S Satheesh Kumar

    2009-01-01

    Full Text Available Patients receiving radiotherapy or chemotherapy will receive some degree of oral mucositis The incidence of oral mucositis was especially high in patients: (i With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii who also received concomitant chemotherapy; (iii who received a total dose over 5,000 cGy; and (iv who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene

  10. Radiation induced pesticidal microbes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants.

  11. Radiation induced pesticidal microbes

    International Nuclear Information System (INIS)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S.

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants

  12. The Degree of Radiation-Induced DNA Strand Breaks Is Altered by Acute Sleep Deprivation and Psychological Stress and Is Associated with Cognitive Performance in Humans.

    Science.gov (United States)

    Moreno-Villanueva, Maria; von Scheven, Gudrun; Feiveson, Alan; Bürkle, Alexander; Wu, Honglu; Goel, Namni

    2018-03-27

    Sleep deprivation is associated with impaired immune responses, cancer, and morbidity and mortality, and can degrade cognitive performance, although individual differences exist in such responses. Sleep deprivation induces DNA strand breaks and DNA base oxidation in animals, and psychological stress is associated with increased DNA damage in humans. It remains unknown whether sleep deprivation or psychological stress in humans affects DNA damage response from environmental stressors, and whether these responses predict cognitive performance during sleep deprivation. Sixteen healthy adults (ages 29-52;mean age±SD, 36.4±7.1 years;7 women) participated in a 5-day experiment involving two 8 hour time-in-bed [TIB] baseline nights, followed by 39 hours total sleep deprivation (TSD), and two 8-10 hour TIB recovery nights. A modified Trier Social Stress Test was conducted on the day after TSD. Psychomotor Vigilance Tests measured behavioral attention. DNA damage was assessed in blood cells collected at 5 time points, and blood cells were irradiated ex-vivo. TSD, alone or in combination with psychological stress, did not induce significant increases in DNA damage. By contrast, radiation-induced DNA damage decreased significantly in response to TSD, but increased back to baseline when combined with psychological stress. Cognitively-vulnerable individuals had more radiation-induced DNA strand breaks before TSD, indicating their greater sensitivity to DNA damage from environmental stressors. Our results provide novel insights into the molecular consequences of sleep deprivation, psychological stress, and performance vulnerability. They are important for situations involving sleep loss, radiation exposure and cognitive deficits, including cancer therapy, environmental toxicology, and space medicine.

  13. Radiation-induced diploid spermatids in mice

    International Nuclear Information System (INIS)

    Hacker-Klom, U.; Heiden, Th.; Otto, F.J.; Goehde, W.; Mauro, F.

    1989-01-01

    Diploid elongated spermatids of mice were enriched by flow cytometry and cell sorting using a new type of sorter (Partec). The sorted abnormal spermatids were identified morphologically and by nuclear area integration. The radiation-induced increase in the frequency of diploid elongated spermatids was monitored with time following acute X-ray exposure of mice. Dose-response curves for acute 60 Co-gamma and 14 MeV neutron irradiations yielded an RBE value of 4.3 for the doubling of the control level. (author)

  14. Radiation-induced diploid spermatids in mice

    Energy Technology Data Exchange (ETDEWEB)

    Hacker-Klom, U; Heiden, Th; Otto, F J; Goehde, W; Mauro, F

    1989-05-01

    Diploid elongated spermatids of mice were enriched by flow cytometry and cell sorting using a new type of sorter (Partec). The sorted abnormal spermatids were identified morphologically and by nuclear area integration. The radiation-induced increase in the frequency of diploid elongated spermatids was monitored with time following acute X-ray exposure of mice. Dose-response curves for acute /sup 60/Co-gamma and 14 MeV neutron irradiations yielded an RBE value of 4.3 for the doubling of the control level. (author).

  15. Radiation-induced meningiomas in pediatric patients

    International Nuclear Information System (INIS)

    Moss, S.D.; Rockswold, G.L.; Chou, S.N.; Yock, D.; Berger, M.S.

    1988-01-01

    Radiation-induced meningiomas rarely have latency periods short enough from the time of irradiation to the clinical presentation of the tumor to present in the pediatric patient. Three cases of radiation-induced intracranial meningiomas in pediatric patients are presented. The first involved a meningioma of the right frontal region in a 10-year-old boy 6 years after the resection and irradiation of a 4th ventricular medulloblastoma. Review of our pediatric tumor cases produced a second case of a left temporal fossa meningioma presenting in a 15-year-old boy with a history of irradiation for retinoblastoma at age 3 years and a third case of a right frontoparietal meningioma in a 15-year-old girl after irradiation for acute lymphoblastic leukemia. Only three cases of meningiomas presenting in the pediatric age group after radiation therapy to the head were detected in our review of the literature

  16. The acute exposure effects of inhaled nickel nanoparticles on murine endothelial progenitor cells.

    Science.gov (United States)

    Liberda, Eric N; Cuevas, Azita K; Qu, Qingshan; Chen, Lung Chi

    2014-08-01

    The discovery of endothelial progenitor cells (EPCs) may help to explain observed cardiovascular effects associated with inhaled nickel nanoparticle exposures, such as increases in vascular inflammation, generation of reactive oxygen species, altered vasomotor tone and potentiated atherosclerosis in murine species. Following an acute whole body inhalation exposure to 500 µg/m(3) of nickel nanoparticles for 5 h, bone marrow EPCs from C57BL/6 mice were isolated. EPCs were harvested for their RNA or used in a variety of assays including chemotaxis, tube formation and proliferation. Gene expression was assessed for important receptors involved in EPC mobilization and homing using RT-PCR methods. EPCs, circulating endothelial progenitor cells (CEPCs), circulating endothelial cells (CECs) and endothelial microparticles (EMPs) were quantified on a BD FACSCalibur to examine endothelial damage and repair associated with the exposure. Acute exposure to inhaled nickel nanoparticles significantly increased both bone marrow EPCs as well as their levels in circulation (CEPCs). CECs were significantly elevated indicating that endothelial damage occurred due to the exposure. There was no significant difference in EMPs between the two groups. Tube formation and chemotaxis, but not proliferation, of bone marrow EPCs was impaired in the nickel nanoparticle exposed group. These results coincided with a decrease in the mRNA of receptors involved in EPC mobilization and homing. These data provide new insight into how an acute nickel nanoparticle exposure to half of the current Occupational Safety & Health Administration (OSHA) permissible exposure limit may adversely affect EPCs and exacerbate cardiovascular disease states.

  17. Rosiglitazone attenuates pulmonary fibrosis and radiation-induced intestinal damage

    International Nuclear Information System (INIS)

    Mangoni, M.; Gerini, C.; Sottili, M.; Cassani, S.; Stefania, G.; Biti, G.; Castiglione, F.; Vanzi, E.; Bottoncetti, A.; Pupi, A.

    2011-01-01

    Full text of publication follows: Purpose.-The aim of the study was to evaluate radioprotective effect of rosiglitazone (RGZ) on a murine model of late pulmonary damage and of acute intestinal damage. Methods.- Lung fibrosis: C57 mice were treated with the radiomimetic agent bleomycin, with or without rosiglitazone (5 mg/kg/day). To obtain an independent qualitative and quantitative measure for lung fibrosis we used high resolution CT, performed twice a week during the entire observation period. Hounsfield Units (HU) of section slides from the upper and lower lung region were determined. On day 31 lungs were collected for histological analysis. Acute intestinal damage: mice underwent 12 Gy total body irradiation with or without rosiglitazone. Mice were sacrificed 24 or 72 h after total body irradiation and ileum and colon were collected. Results.- Lung fibrosis: after bleomycin treatment, mice showed typical CT features of lung fibrosis, including irregular septal thickening and patchy peripheral reticular abnormalities. Accordingly, HU lung density was dramatically increased. Rosiglitazone markedly attenuated the radiological signs of fibrosis and strongly inhibited HU lung density increase (60% inhibition at the end of the observation period). Histological analysis revealed that in bleomycin-treated mice, fibrosis involved 50-55% of pulmonary parenchyma and caused an alteration of the alveolar structures in 10% of parenchyma, while in rosiglitazone-treated mice, fibrosis involved only 20-25% of pulmonary parenchyma, without alterations of the alveolar structures. Acute intestinal damage: 24 h after 12 Gy of total body irradiation intestinal mucosa showed villi shortening, mucosal thickness and crypt necrotic changes. Rosiglitazone showed a histological improvement of tissue structure, with villi and crypts normalization and oedema reduction. Conclusion.- These results demonstrate that rosiglitazone displays a protective effect on pulmonary fibrosis and radiation-induced

  18. Rosiglitazone attenuates pulmonary fibrosis and radiation-induced intestinal damage

    Energy Technology Data Exchange (ETDEWEB)

    Mangoni, M.; Gerini, C.; Sottili, M.; Cassani, S.; Stefania, G.; Biti, G. [Radiotherapy Unit, Clinical Physiopathology Department, University of Florence, Firenze (Italy); Castiglione, F. [Department of Human Pathology and Oncology, University of Florence, Firenze (Italy); Vanzi, E.; Bottoncetti, A.; Pupi, A. [Nuclear Medicine Unit, Clinical Physiopathology Department, University of Florence, Firenze (Italy)

    2011-10-15

    Full text of publication follows: Purpose.-The aim of the study was to evaluate radioprotective effect of rosiglitazone (RGZ) on a murine model of late pulmonary damage and of acute intestinal damage. Methods.- Lung fibrosis: C57 mice were treated with the radiomimetic agent bleomycin, with or without rosiglitazone (5 mg/kg/day). To obtain an independent qualitative and quantitative measure for lung fibrosis we used high resolution CT, performed twice a week during the entire observation period. Hounsfield Units (HU) of section slides from the upper and lower lung region were determined. On day 31 lungs were collected for histological analysis. Acute intestinal damage: mice underwent 12 Gy total body irradiation with or without rosiglitazone. Mice were sacrificed 24 or 72 h after total body irradiation and ileum and colon were collected. Results.- Lung fibrosis: after bleomycin treatment, mice showed typical CT features of lung fibrosis, including irregular septal thickening and patchy peripheral reticular abnormalities. Accordingly, HU lung density was dramatically increased. Rosiglitazone markedly attenuated the radiological signs of fibrosis and strongly inhibited HU lung density increase (60% inhibition at the end of the observation period). Histological analysis revealed that in bleomycin-treated mice, fibrosis involved 50-55% of pulmonary parenchyma and caused an alteration of the alveolar structures in 10% of parenchyma, while in rosiglitazone-treated mice, fibrosis involved only 20-25% of pulmonary parenchyma, without alterations of the alveolar structures. Acute intestinal damage: 24 h after 12 Gy of total body irradiation intestinal mucosa showed villi shortening, mucosal thickness and crypt necrotic changes. Rosiglitazone showed a histological improvement of tissue structure, with villi and crypts normalization and oedema reduction. Conclusion.- These results demonstrate that rosiglitazone displays a protective effect on pulmonary fibrosis and radiation-induced

  19. Acute lethal toxicity following passive immunization for treatment of murine cryptococcosis.

    Science.gov (United States)

    Savoy, A C; Lupan, D M; Manalo, P B; Roberts, J S; Schlageter, A M; Weinhold, L C; Kozel, T R

    1997-01-01

    Passive immunization with monoclonal antibodies (MAbs) specific for the major capsular polysaccharide of Cryptococcus neoformans alters the course of murine cryptococcosis. During studies of passive immunization for treatment of murine cryptococcosis, we noted the occurrence of an acute, lethal toxicity. Toxicity was characterized by scratching, lethargy, respiratory distress, collapse, and death within 20 to 60 min after injection of antibody. The toxic effect was observed only in mice with a cryptococcal infection and was reduced or absent in the early and late stages of disease. The clinical course and histopathology were consistent with those for shock. There was considerable variation between mouse strains in susceptibility to toxicity. Swiss Webster mice from the Charles River colony were most susceptible, followed by C3H/He, BALB/c, and C57BL/6 mice. DBA/2 mice and Swiss Webster mice from the Simonsen colony were resistant. Acute toxicity was mimicked by injection of preformed complexes of MAb and purified polysaccharide. The toxic effect was also produced by injection of MAbs into mice that were preloaded with polysaccharide. The toxic effect was not blocked by treatment of mice with chloropheniramine or anti-tumor necrosis factor alpha antibodies or by depletion of complement components via pretreatment with cobra venom factor. Toxicity was reduced by treatment of mice with high doses of epinephrine, dexamethasone, or chlorpromazine. Finally, the toxic effect was completely blocked by treatment of mice with the platelet-activating factor antagonist WEB 2170 BS or by pretreatment of mice with the liposome-encapsulated drug dichloromethylene diphosphonate, a procedure which depletes macrophages from the spleen and liver. PMID:9125564

  20. Radiation-induced cerebrovasculopathy

    International Nuclear Information System (INIS)

    Ikeyama, Yukihide; Abiko, Seisho; Kurokawa, Yasushi; Okamura, Tomomi; Watanabe, Kohsaku; Inoue, Shinichi; Fujii, Yasuhiro.

    1993-01-01

    We reported a patient who suffered from cerebrovasculopathy after irradiation therapy for astrocytoma located at the left temporal lobe. An eleven year-old boy who presented with headache and vomiting received partial removal of a tumor. Histological diagnosis of the tumor was astrocytoma (grade II). His preoperative cerebral angiograms showed mass sign solely, without stenosis or occlusion of the cerebral vessel. Postoperatively, he was treated with irradiation therapy involving the whole brain with a total of 30 Gy, and gamma knife therapy. Six months after irradiation, he started suffering from frequent cerebral ischemic attacks, but there was no regrowth of the tumor visible on CT scans. Cerebral angiograms were made again, and revealed multifocal stenoses in the bilateral internal carotid arteries, middle cerebral arteries, and the anterior cerebral artery. His symptoms did not improve after conservative treatment with steroids, calcium antagonist, or low molecular weight dextran. Although he received a superficial temporal artery-middle cerebral artery (STA-MCA) anastomoses bilaterally, multiple cerebral infarctions appeared. Although irradiation therapy is acceptable in patients with brain tumor, cerebrovasculopathy after irradiation should be considered as one of the most important complications, and the risk incurred by irradiation therapy should lead to more careful consideration and caution when treating intracranial brain tumors, especially in children. From our experience, the usefulness of bypass surgery for radiation-induced cerebrovasculopathy is still controversial. (author)

  1. Radiation induced nano structures

    International Nuclear Information System (INIS)

    Ibragimova, E.M.; Kalanov, M.U.; Khakimov, Z.

    2006-01-01

    Full text: Nanometer-size silicon clusters have been attracting much attention due to their technological importance, in particular, as promising building blocks for nano electronic and nano photonic systems. Particularly, silicon wires are of great of interest since they have potential for use in one-dimensional quantum wire high-speed field effect transistors and light-emitting devices with extremely low power consumption. Carbon and metal nano structures are studied very intensely due to wide possible applications. Radiation material sciences have been dealing with sub-micron objects for a long time. Under interaction of high energy particles and ionizing radiation with solids by elastic and inelastic mechanisms, at first point defects are created, then they form clusters, column defects, disordered regions (amorphous colloids) and finally precipitates of another crystal phase in the matrix. Such irradiation induced evolution of structure defects and phase transformations was observed by X-diffraction techniques in dielectric crystals of quartz and corundum, which exist in and crystal modifications. If there is no polymorphism, like in alkali halide crystals, then due to radiolysis halogen atoms are evaporated from the surface that results in non-stoichiometry or accumulated in the pores formed by metal vacancies in the sub-surface layer. Nano-pores are created by intensive high energy particles irradiation at first chaotically and then they are ordered and in part filled by inert gas. It is well-known mechanism of radiation induced swelling and embrittlement of metals and alloys, which is undesirable for construction materials for nuclear reactors. Possible solution of this problem may come from nano-structured materials, where there is neither swelling nor embrittlement at gas absorption due to very low density of the structure, while strength keeps high. This review considers experimental observations of radiation induced nano-inclusions in insulating

  2. Radiation-induced brain injury: A review

    Energy Technology Data Exchange (ETDEWEB)

    Greene-Schloesser, Dana; Robbins, Mike E.; Peiffer, Ann M.; Shaw, Edward G. [Department of Radiation Oncology, Wake Forest School of Medicine,, Winston-Salem, NC (United States); Brain Tumor Center of Excellence, Wake Forest School of Medicine,, Winston-Salem, NC (United States); Wheeler, Kenneth T. [Brain Tumor Center of Excellence, Wake Forest School of Medicine,, Winston-Salem, NC (United States); Department of Radiology, Wake Forest School of Medicine,, Winston-Salem, NC (United States); Chan, Michael D., E-mail: mrobbins@wakehealth.edu [Department of Radiation Oncology, Wake Forest School of Medicine,, Winston-Salem, NC (United States); Brain Tumor Center of Excellence, Wake Forest School of Medicine,, Winston-Salem, NC (United States)

    2012-07-19

    Approximately 100,000 primary and metastatic brain tumor patients/year in the US survive long enough (>6 months) to experience radiation-induced brain injury. Prior to 1970, the human brain was thought to be highly radioresistant; the acute CNS syndrome occurs after single doses >30 Gy; white matter necrosis occurs at fractionated doses >60 Gy. Although white matter necrosis is uncommon with modern techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become important, because they have profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenesis of radiation-induced cognitive impairment. Given its central role in memory and neurogenesis, the majority of these studies have focused on the hippocampus. Irradiating pediatric and young adult rodent brains leads to several hippocampal changes including neuroinflammation and a marked reduction in neurogenesis. These data have been interpreted to suggest that shielding the hippocampus will prevent clinical radiation-induced cognitive impairment. However, this interpretation may be overly simplistic. Studies using older rodents, that more closely match the adult human brain tumor population, indicate that, unlike pediatric and young adult rats, older rats fail to show a radiation-induced decrease in neurogenesis or a loss of mature neurons. Nevertheless, older rats still exhibit cognitive impairment. This occurs in the absence of demyelination and/or white matter necrosis similar to what is observed clinically, suggesting that more subtle molecular, cellular and/or microanatomic modifications are involved in this radiation-induced brain injury. Given that radiation-induced cognitive impairment likely reflects damage to both hippocampal- and non-hippocampal-dependent domains, there is a critical need to investigate the microanatomic and functional effects of radiation in various brain regions as well as their

  3. Radiation-induced brain injury: A review

    International Nuclear Information System (INIS)

    Greene-Schloesser, Dana; Robbins, Mike E.; Peiffer, Ann M.; Shaw, Edward G.; Wheeler, Kenneth T.; Chan, Michael D.

    2012-01-01

    Approximately 100,000 primary and metastatic brain tumor patients/year in the US survive long enough (>6 months) to experience radiation-induced brain injury. Prior to 1970, the human brain was thought to be highly radioresistant; the acute CNS syndrome occurs after single doses >30 Gy; white matter necrosis occurs at fractionated doses >60 Gy. Although white matter necrosis is uncommon with modern techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become important, because they have profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenesis of radiation-induced cognitive impairment. Given its central role in memory and neurogenesis, the majority of these studies have focused on the hippocampus. Irradiating pediatric and young adult rodent brains leads to several hippocampal changes including neuroinflammation and a marked reduction in neurogenesis. These data have been interpreted to suggest that shielding the hippocampus will prevent clinical radiation-induced cognitive impairment. However, this interpretation may be overly simplistic. Studies using older rodents, that more closely match the adult human brain tumor population, indicate that, unlike pediatric and young adult rats, older rats fail to show a radiation-induced decrease in neurogenesis or a loss of mature neurons. Nevertheless, older rats still exhibit cognitive impairment. This occurs in the absence of demyelination and/or white matter necrosis similar to what is observed clinically, suggesting that more subtle molecular, cellular and/or microanatomic modifications are involved in this radiation-induced brain injury. Given that radiation-induced cognitive impairment likely reflects damage to both hippocampal- and non-hippocampal-dependent domains, there is a critical need to investigate the microanatomic and functional effects of radiation in various brain regions as well as their

  4. Clinical and Epidemiological Characteristics of Scrub Typhus and Murine Typhus among Hospitalized Patients with Acute Undifferentiated Fever in Northern Vietnam

    Science.gov (United States)

    Hamaguchi, Sugihiro; Cuong, Ngo Chi; Tra, Doan Thu; Doan, Yen Hai; Shimizu, Kenta; Tuan, Nguyen Quang; Yoshida, Lay-Myint; Mai, Le Quynh; Duc-Anh, Dang; Ando, Shuji; Arikawa, Jiro; Parry, Christopher M.; Ariyoshi, Koya; Thuy, Pham Thanh

    2015-01-01

    A descriptive study on rickettsiosis was conducted at the largest referral hospital in Hanoi, Vietnam, to identify epidemiological and clinical characteristics of specific rickettsiosis. Between March 2001 and February 2003, we enrolled 579 patients with acute undifferentiated fever (AUF), excluding patients with malaria, dengue fever, and typhoid fever, and serologically tested for Orientia tsutsugamushi and Rickettsia typhi. Of the patients, 237 (40.9%) and 193 (33.3%) had scrub and murine typhus, respectively, and 149 (25.7%) had neither of them (non–scrub and murine typhus [non-ST/MT]). The proportion of murine typhus was highest among patients living in Hanoi whereas that of scrub typhus was highest in national or regional border areas. The presence of an eschar, dyspnea, hypotension, and lymphadenopathy was significantly associated with a diagnosis of scrub typhus (OR = 46.56, 10.90, 9.01, and 7.92, respectively). Patients with murine typhus were less likely to have these findings but more likely to have myalgia, rash, and relative bradycardia (OR = 1.60, 1.56, and 1.45, respectively). Scrub typhus and murine typhus were shown to be common causes of AUF in northern Vietnam although the occurrence of spotted fever group rickettsiae was not determined. Clinical and epidemiological information may help local clinicians make clinical diagnosis of specific rickettsioses in a resource-limited setting. PMID:25778504

  5. Human cardiac-derived adherent proliferating cells reduce murine acute Coxsackievirus B3-induced myocarditis.

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    Kapka Miteva

    Full Text Available BACKGROUND: Under conventional heart failure therapy, inflammatory cardiomyopathy typically has a progressive course, indicating a need for alternative therapeutic strategies to improve long-term outcomes. We recently isolated and identified novel cardiac-derived cells from human cardiac biopsies: cardiac-derived adherent proliferating cells (CAPs. They have similarities with mesenchymal stromal cells, which are known for their anti-apoptotic and immunomodulatory properties. We explored whether CAPs application could be a novel strategy to improve acute Coxsackievirus B3 (CVB3-induced myocarditis. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate the safety of our approach, we first analyzed the expression of the coxsackie- and adenovirus receptor (CAR and the co-receptor CD55 on CAPs, which are both required for effective CVB3 infectivity. We could demonstrate that CAPs only minimally express both receptors, which translates to minimal CVB3 copy numbers, and without viral particle release after CVB3 infection. Co-culture of CAPs with CVB3-infected HL-1 cardiomyocytes resulted in a reduction of CVB3-induced HL-1 apoptosis and viral progeny release. In addition, CAPs reduced CD4 and CD8 T cell proliferation. All CAPs-mediated protective effects were nitric oxide- and interleukin-10-dependent and required interferon-γ. In an acute murine model of CVB3-induced myocarditis, application of CAPs led to a decrease of cardiac apoptosis, cardiac CVB3 viral load and improved left ventricular contractility parameters. This was associated with a decline in cardiac mononuclear cell activity, an increase in T regulatory cells and T cell apoptosis, and an increase in left ventricular interleukin-10 and interferon-γ mRNA expression. CONCLUSIONS: We conclude that CAPs are a unique type of cardiac-derived cells and promising tools to improve acute CVB3-induced myocarditis.

  6. A report on radiation-induced gliomas

    International Nuclear Information System (INIS)

    Salvati, M.; Artico, M.; Caruso, R.; Rocchi, G.; Orlando, E.R.; Nucci, F.

    1991-01-01

    Radiation-induced gliomas are uncommon, with only 73 cases on record to date. The disease that most frequently occasioned radiation therapy has been acute lymphoblastic leukemia (ALL). Three more cases are added here, two after irradiation for ALL and one after irradiation for tinea capitis. In a review of the relevant literature, the authors stress the possibility that the ALL-glioma and the retinoblastoma-glioma links point to syndromes in their own right that may occur without radiation therapy.56 references

  7. Radiation induced liver disease: A clinical update

    International Nuclear Information System (INIS)

    Benson, R.; Madan, R.; Chander, S.; Kilambi, R.

    2016-01-01

    Radiation-induced liver disease (RILD) or radiation hepatitis is a sub-acute form of liver injury due to radiation. It is one of the most dreaded complications of radiation which prevents radiation dose escalation and re irradiation for hepatobiliary or upper gastrointestinal malignancies. This complication should be kept in mind whenever a patient is planned for irradiation of these malignancies. Although, incidence of RILD is decreasing due to better knowledge of liver tolerance, improved investigation modalities and modern radiation delivery techniques, treatment options are still limited. In this review article, we have focussed on pathophysiology, risk factors, prevention and management of RILD

  8. Prevention and treatment of acute radiation-induced skin reactions: a systematic review and meta-analysis of randomized controlled trials

    International Nuclear Information System (INIS)

    Chan, Raymond Javan; Webster, Joan; Chung, Bryan; Marquart, Louise; Ahmed, Muhtashimuddin; Garantziotis, Stuart

    2014-01-01

    Radiation-induced skin reaction (RISR) is a common side effect that affects the majority of cancer patients receiving radiation treatment. RISR is often characterised by swelling, redness, pigmentation, fibrosis, and ulceration, pain, warmth, burning, and itching of the skin. The aim of this systematic review was to assess the effects of interventions which aim to prevent or manage RISR in people with cancer. We searched the following databases up to November 2012: Cochrane Skin Group Specialised Register, CENTRAL (2012, Issue 11), MEDLINE (from 1946), EMBASE (from 1974), PsycINFO (from 1806), CINAHL (from 1981) and LILACS (from 1982). Randomized controlled trials evaluating interventions for preventing or managing RISR in cancer patients were included. The primary outcomes were development of RISR, and levels of RISR and symptom severity. Secondary outcomes were time taken to develop erythema or dry desquamation; quality of life; time taken to heal, a number of skin reaction and symptom severity measures; cost, participant satisfaction; ease of use and adverse effects. Where appropriate, we pooled results of randomized controlled trials using mean differences (MD) or odd ratios (OR) with 95% confidence intervals (CI). Forty-seven studies were included in this review. These evaluated six types of interventions (oral systemic medications; skin care practices; steroidal topical therapies; non-steroidal topical therapies; dressings and other). Findings from two meta-analyses demonstrated significant benefits of oral Wobe-Mugos E for preventing RISR (OR 0.13 (95% CI 0.05 to 0.38)) and limiting the maximal level of RISR (MD -0.92 (95% CI -1.36 to -0.48)). Another meta-analysis reported that wearing deodorant does not influence the development of RISR (OR 0.80 (95% CI 0.47 to 1.37)). Despite the high number of trials in this area, there is limited good, comparative research that provides definitive results suggesting the effectiveness of any single intervention for

  9. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hematopoietic injury. Estimulacion proliferativa de celulas madre hematopoyeticas de raton por actividades circulantes producidas durante la recuperacion de un dano hematopoyetico radioinducido

    Energy Technology Data Exchange (ETDEWEB)

    Grande Azanedo, M.T.

    1989-02-01

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e., radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU-S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hematopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation.

  10. Evaluation of late radiation-induced changes of the superficial microcirculation after acute β-irradiation. II. prognostic importance of the cutaneous doppler laser

    International Nuclear Information System (INIS)

    Lefaix, J.L.; Delanian, S.

    2000-01-01

    Objective. -The changes that occur in the tissular microcirculation after accidental acute irradiation account for some of the early effects of such irradiation, especially at the cutaneous level. The prognostic importance of the cutaneous laser doppler was tested in an experimental model of acute β-irradiation. Methods.-Ten pigs were given β-irradiation with a high single localized dose of 90 Sr/ 90 Y (32 or 64 Gy, 7 mg/cm 2 ) delivered to the flank, and were evaluated 2, 7, 14, 21 and 28 days thereafter. Each individual was its own control. The local microcirculation was measured in the resting state and during thermal stimulation at 42 deg. C, using a Periflux cutaneous Doppler laser with p413 probes. Three periods of six minutes each were continuously recorded: period 1 (P1) represented basal resting cutaneous perfusion, with the slope p corresponding to the increase in perfusion when two minutes of thermal stimulation at 42 deg. C began; P2 to plateau perfusion during this stimulation; and P3 to perfusion on the return to equilibrium. Results. -After acute β-irradiation in the pig, all the cutaneous microcirculation parameters measured (P1, p, P2 and P3) had risen at day 2 in the irradiated area by a factor of 2 to 4, depending on the dose (p < 0.001), compared to the adjacent control area. On the other hand, as from day 7, the resting and the stimulated microcirculation varied little, except for a reduction of the slope p by a factor of 2 (p < 0.05) after the strongest radiation dose. Conclusion. -After acute irradiation, the increase in the resting cutaneous microcirculation may correspond to immediate but transitory capillary vasodilatation that accompanies the initial erythema in accidental irradiation. The absence of vascular response to thermal stimulation seems to be a good means of reaching an early diagnosis of delayed cutaneous radiation necrosis. (authors)

  11. Control of radiation-induced diarrhea with cholestyramine

    International Nuclear Information System (INIS)

    Heusinkveld, R.S.; Manning, M.R.; Aristizabal, S.A.

    1978-01-01

    Cholestyramine is a non-absorbable ion-exchange resin which specifically binds bile salts. We have treated seven patients with acute or chronic radiation-induced diarrhea that was refractory to the usual methods of control with cholestyramine. In each case, the diarrhea was controlled with cholestyramine. This observation supports previous experimental work with animals which indicated that bile salts contribute to the genesis of radiation-induced diarrhea. Cholestyramine is well-tolerated, but should not be administered with certain oral medications. The results of this small series are preliminary, but point the way toward a more extensive clinical trial to define the usefulness of cholestyramine in the treatment of refractory acute or chronic radiation-induced diarrhea

  12. Murine model of acute myocarditis and cerebral cortical neuron edema induced by coxsackievirus B4

    Directory of Open Access Journals (Sweden)

    Zhao-Peng Dong

    2018-01-01

    Full Text Available Globally, coxsackievirus B4 (CV-B4 has been continuously isolated and evidence suggests an association with the development of pancreatitis and type I diabetes. In addition, CV-B4 is also associated with myocarditis and severe central nervous system (CNS complications, which remain poorly studied and understood. In the present study, we established an ICR mouse model of CV-B4 infection and examined whether CV-B4 infection resulted in a predisposition to myocarditis and CNS infection. We found high survival in both the treatment and control group, with no significant differences in clinical outcomes observed. However, pathological lesions were evident in both brain and heart tissue of the CV-B4-infected mice. In addition, high viral loads were found in the neural and cardiac tissues as early as 2 d postinfection. Expressions of IFN-γ and IL-6 in sera were significantly higher in CV-B4-infected mice compared to uninfected negative controls, suggesting the involvement of these cytokines in the development of histopathological lesions. Our murine model successfully reproduced the acute myocarditis and cerebral cortical neuron edema induced by CV-B4, and may be useful for the evaluation of vaccine candidates and potential antivirals against CV-B4 infection.

  13. Acute Noise Exposure Is Associated With Intrinsic Apoptosis in Murine Central Auditory Pathway

    Directory of Open Access Journals (Sweden)

    Moritz Gröschel

    2018-05-01

    Full Text Available Noise that is capable of inducing the hearing loss (NIHL has a strong impact on the inner ear structures and causes early and most obvious pathophysiological changes in the auditory periphery. Several studies indicated that intrinsic apoptotic cell death mechanisms are the key factors inducing cellular degeneration immediately after noise exposure and are maintained for days or even weeks. In addition, studies demonstrated several changes in the central auditory system following noise exposure, consistent with early apoptosis-related pathologies. To clarify the underlying mechanisms, the present study focused on the noise-induced gene and protein expression of the pro-apoptotic protease activating factor-1 (APAF1 and the anti-apoptotic B-cell lymphoma 2 related protein a1a (BCL2A1A in the cochlear nucleus (CN, inferior colliculus (IC and auditory cortex (AC of the murine central auditory pathway. The expression of Bcl2a1a mRNA was upregulated immediately after trauma in all tissues investigated, whereas the protein levels were significantly reduced at least in the auditory brainstem. Conversely, acute noise has decreased the expression of Apaf1 gene along the auditory pathway. The changes in APAF1 protein level were not statistically significant. It is tempting to speculate that the acoustic overstimulation leads to mitochondrial dysfunction and induction of apoptosis by regulation of proapoptotic and antiapoptotic proteins. The inverse expression pattern on the mRNA level of both genes might reflect a protective response to decrease cellular damage. Our results indicate the immediate presence of intrinsic apoptosis following noise trauma. This, in turn, may significantly contribute to the development of central structural deficits. Auditory pathway-specific inhibition of intrinsic apoptosis could be a therapeutic approach for the treatment of acute (noise-induced hearing loss to prevent irreversible neuronal injury in auditory brain structures

  14. Modeling the Risk of Radiation-Induced Acute Esophagitis for Combined Washington University and RTOG Trial 93-11 Lung Cancer Patients

    International Nuclear Information System (INIS)

    Huang, Ellen X.; Bradley, Jeffrey D.; El Naqa, Issam; Hope, Andrew J.; Lindsay, Patricia E.; Bosch, Walter R.; Matthews, John W.; Sause, William T.; Graham, Mary V.; Deasy, Joseph O.

    2012-01-01

    Purpose: To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non–small-cell lung cancer. Methods and Materials: The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose–volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. Results: The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior–inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 ∗ MED+1.50 ∗ ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Conclusions: Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis

  15. Modeling the Risk of Radiation-Induced Acute Esophagitis for Combined Washington University and RTOG Trial 93-11 Lung Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ellen X.; Bradley, Jeffrey D.; El Naqa, Issam [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO (United States); Hope, Andrew J.; Lindsay, Patricia E. [Princess Margaret Hospital, Toronto, ON (Canada); Bosch, Walter R.; Matthews, John W. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO (United States); Sause, William T. [Department of Radiation Oncology, LDS Hospital, Salt Lake City, UT (United States); Graham, Mary V. [Department of Radiation Oncology, Phelps County Regional Hospital, Rolla, MO (United States); Deasy, Joseph O., E-mail: deasyj@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-04-01

    Purpose: To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non-small-cell lung cancer. Methods and Materials: The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose-volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. Results: The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior-inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 Asterisk-Operator MED+1.50 Asterisk-Operator ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Conclusions: Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts

  16. Modeling the risk of radiation-induced acute esophagitis for combined Washington University and RTOG trial 93-11 lung cancer patients.

    Science.gov (United States)

    Huang, Ellen X; Bradley, Jeffrey D; El Naqa, Issam; Hope, Andrew J; Lindsay, Patricia E; Bosch, Walter R; Matthews, John W; Sause, William T; Graham, Mary V; Deasy, Joseph O

    2012-04-01

    To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non-small-cell lung cancer. The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose-volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior-inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 MED+1.50 ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis risk in combined-data WUSTL and RTOG 93-11 trial datasets. Copyright

  17. Effect of aging on airway remodeling and muscarinic receptors in a murine acute asthma model

    Directory of Open Access Journals (Sweden)

    Kang JY

    2013-10-01

    Full Text Available Ji Young Kang, Sook Young Lee, Chin Kook Rhee, Seung Joon Kim, Soon Seog Kwon, Young Kyoon KimDepartment of Internal Medicine, College of Medicine, Catholic University of Korea, Seoul, KoreaBackground and objectives: The influence of aging on the development of asthma has not been studied thoroughly. The aim of this study was to investigate age-related airway responses involving lung histology and expression of muscarinic receptors in a murine model of acute asthma. Methods: Female BALB/c mice at the ages of 6 weeks and 6, 9, and 12 months were sensitized and challenged with ovalbumin (OVA for 1 month (n = 8–12 per group. We analyzed inflammatory cells and T-helper (Th2 cytokines in bronchoalveolar lavage (BAL fluid and parameters of airway remodeling and expression of muscarinic receptors in lung tissue. Results: Among the OVA groups, total cell and eosinophil numbers in BAL fluid were significantly higher in the older (6-, 9-, and 12-month-old mice than in the young (6-week-old mice. Interleukin (IL 4 (IL-4 concentration increased, but IL-5 and IL-13 concentrations showed a decreased tendency, with age. IL-17 concentration tended to increase with age, which did not reach statistical significance. periodic acid-Schiff (PAS staining area, peribronchial collagen deposition, and area of α-smooth muscle staining were significantly higher in the 6-month older OVA group than in the young OVA group. The expression of the M3 and M2 muscarinic receptors tended to increase and decrease, respectively, with age. Conclusion: The aged mice showed an active and unique pattern not only on airway inflammation, but also on airway remodeling and expression of the muscarinic receptors during the development of acute asthma compared with the young mice. These findings suggest that the aging process affects the pathogenesis of acute asthma and age-specific approach might be more appropriate for better asthma control in a clinical practice.Keywords: aging, asthma

  18. Radiation-induced acute myeloid leukemia in the mouse: experimental observations in vivo with implications for hypotheses about the basis of carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Mole, R H

    1986-01-01

    Acute myeloid leukaemia induction by X- and ..gamma..-rays in 4 mouse strains follows the same dose-response aD/sup 2/esup(-lambdaD). The (dose)/sup 2/ interaction disappears within 3 days. AML appears earlier when syngeneic marrow cells are injected 3 days after irradiation, minimum latent period and final frequency remaining unchanged. Dose-responses for brief and protracted exposures are quite different for non-myeloid 'leukemia'. The results seem incompatible with a common model for initiation of both leukaemia categories and with orthodox concepts that initiation is a stable state and must be followed by multiple events over a period of time before cells express fully malignant behaviour.

  19. Radiation-induced acute myeloid leukemia in the mouse: experimental observations in vivo with implications for hypotheses about the basis of carcinogenesis

    International Nuclear Information System (INIS)

    Mole, R.H.

    1986-01-01

    Acute myeloid leukaemia induction by X- and γ-rays in 4 mouse strains follows the same dose-response aD 2 esup(-lambdaD). The (dose) 2 interaction disappears within 3 days. AML appears earlier when syngeneic marrow cells are injected 3 days after irradiation, minimum latent period and final frequency remaining unchanged. Dose-responses for brief and protracted exposures are quite different for non-myeloid 'leukemia'. The results seem incompatible with a common model for initiation of both leukaemia categories and with orthodox concepts that initiation is a stable state and must be followed by multiple events over a period of time before cells express fully malignant behaviour. (author)

  20. The use of human recombinant interleukins 1α- and 1β as an early therapy for the cases of an acute radiation-induced disease (experimental)

    International Nuclear Information System (INIS)

    Rogacheva, S.A.; Simbirtsev, A.S.

    1997-01-01

    Paper presents publications devoted to investigation: therapeutic efficiency of IL-1α interleukins during radio biologic experiment conducted using mice, as well as, IL-1α and IL-1β ones in experiments conducted on dogs. Mice were irradiated using 8.7, 9.0, 9.3 and 9.6 Gy doses, while dogs-using 3.15 Gy dose. Power of the absorbed dose constituted 158 c Gy/min. Recombinant IL-1α and IL-1β are shown to affect therapeutically at acute radiation. The optimal therapeutic dose of IL-1 for mice was a dose equal to 100.0 μgxkg -1 (rise of survival rate at CD 70 by 50%, while at CD 100 by 17%); for dogs - 1.0 μgxkg -1 (rise of survival rate at CD 100 at the background of antibacterial therapy up to 80%)

  1. Radiation-induced enteropathy

    Energy Technology Data Exchange (ETDEWEB)

    Sher, M.E.; Bauer, J. (Mount Sinai Hospital, New York, NY (USA))

    1990-02-01

    The incidence of chronic radiation enteritis appears to have risen in recent years due to the increasing utilization of radiotherapy for abdominal and pelvic malignancies. The etiology, pathogenesis, and management of radiation enteritis are discussed. Two case reports exemplify the progressive nature of the disease. Case 1 demonstrates the classical picture of multiple exacerbations and remissions of partial small bowel obstruction and the eventual need for surgical management ten years after radiation therapy. Case 2 presents the more severe sequelae of an acute perforation with a 14-yr latency period. Predisposing factors in the progression of radiation injury include excessive radiation, underlying cardiovascular disease, fixation of the bowel, and an asthenic habitus. In both cases, radiation injury was localized to a discrete segment of bowel; therefore, resection with a primary end-to-end anastomosis was performed. In addition, diseased bowel was eliminated and, therefore, would not cause further complications such as intractable bleeding or fistula formation. The review focuses on current knowledge which may be applied to the treatment and prevention of radiation enteritis.

  2. Thioredoxin mitigates radiation-induced hematopoietic stem cell injury in mice

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    Pasupathi Sundaramoorthy

    2017-11-01

    Full Text Available Abstract Background Radiation exposure poses a significant threat to public health. Hematopoietic injury is one of the major manifestations of acute radiation sickness. Protection and/or mitigation of hematopoietic stem cells (HSCs from radiation injury is an important goal in the development of medical countermeasure agents (MCM. We recently identified thioredoxin (TXN as a novel molecule that has marked protective and proliferative effects on HSCs. In the current study, we investigated the effectiveness of TXN in rescuing mice from a lethal dose of total body radiation (TBI and in enhancing hematopoietic reconstitution following a lethal dose of irradiation. Methods We used in-vivo and in-vitro methods to understand the biological and molecular mechanisms of TXN on radiation mitigation. BABL/c mice were used for the survival study and a flow cytometer was used to quantify the HSC population and cell senescence. A hematology analyzer was used for the peripheral blood cell count, including white blood cells (WBCs, red blood cells (RBCs, hemoglobin, and platelets. Colony forming unit (CFU assay was used to study the colongenic function of HSCs. Hematoxylin and eosin staining was used to determine the bone marrow cellularity. Senescence-associated β-galactosidase assay was used for cell senescence. Western blot analysis was used to evaluate the DNA damage and senescence protein expression. Immunofluorescence staining was used to measure the expression of γ-H2AX foci for DNA damage. Results We found that administration of TXN 24 h following irradiation significantly mitigates BALB/c mice from TBI-induced death: 70% of TXN-treated mice survived, whereas only 25% of saline-treated mice survived. TXN administration led to enhanced recovery of peripheral blood cell counts, bone marrow cellularity, and HSC population as measured by c-Kit+Sca-1+Lin– (KSL cells, SLAM + KSL cells and CFUs. TXN treatment reduced cell senescence and radiation-induced

  3. Radiation induced crosslinking of polytetrafluoroethylene

    International Nuclear Information System (INIS)

    Oshima, Akihiro; Tabata, Yoneho; Ikeda, Shigetoshi; Otsuhata, Kazushige; Kudoh, Hisaaki; Seguchi, Tadao.

    1995-01-01

    The Irradiation temperature effect on polytetrafluoroethylene (PTFE) from room temperature to 380degC was investigated by tensile test and thermal analysis. The behavior of tensile properties and changes of crystallinity on irradiation indicated the formation of a network structure in PTFE by radiation induced crosslinking in inert gas in the molten state just above the melting temperature of PTFE (327degC). The crosslinked PTFE showed a much improved radiation resistance in an atmospheric radiation field. (author)

  4. Radiation-induced chromosomal instability

    International Nuclear Information System (INIS)

    Ritter, S.

    1999-01-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/μm) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  5. Radiation-induced heart injury

    International Nuclear Information System (INIS)

    Suzuki, Yoshihiko; Niibe, Hideo

    1975-01-01

    In order to identify radiation-induced heart injury and to differentiate it from heart disease, an attempt was made to clarify post-irradiation heart injury by investigating the histological changes which occur during the internal between the irradiation and the time of demonstrable histological changes. A study was made of 83 autopsies in which most of the primary neoplasms were breast cancers, lung cancers and mediastinal tumors. In 43 of these autopsies the heart had been irradiated. Sixty eight dd-strain mice were also used for microautoradiographic study. Histological changes in the heart were observed in 27 of the 43 cases receiving irradiation. The limit of the tolerance dose to the heart for indicating histological changes was 1220 ret in humans. The latent period without histological changes was 2.7 months after initiation of radiation therapy. Greater heart injury was observed after re-irradiation or after the combined therapy of radiation and chemotherapy especially mitomycin (MMC). The histological findings after treatment with MMC were similar to those of radiation-induced heart injury. Results of the study indicate that the damage is secondary to radiation-induced changes of the vascula connective tissue. (Evans, G.)

  6. Radiation-induced lesions of the aorta

    Energy Technology Data Exchange (ETDEWEB)

    Doessing, M; Rasmussen, S [Medical Department C, Diakonissestiftelsen, Copenhagen (Denmark); Fischer-Hansen, B; Walbom-Joergensen, S

    1977-04-09

    A description is given of pathological changes detected in the aortic arch of a 21-year-old man. The patient died from an acute myocardial infarction 16 months after a dose of 3696 rads to a mantle field for Hodgkin's disease confined to the midcervical lymph nodes on the left side of the neck. Histological examination of the exposed part of the aortic arch showed the wall to be focally thickened owing to a pronounced fibrosis of the luminal third of the wall. The elastic lamellae in this area were reduced in number, broken up, and haphazardly arranged. The intima appeared normal. There was no leucocytic infiltration, no proliferation of vasa vasorum and no significant adventitial fibrosis. It is suggested that these noncharacteristic changes may have been early radiation-induced lesions which later might induce fibrotic scarring with perhaps clinically evident disease.

  7. Antibody blockade of IL-17 family cytokines in immunity to acute murine oral mucosal candidiasis.

    Science.gov (United States)

    Whibley, Natasha; Tritto, Elaine; Traggiai, Elisabetta; Kolbinger, Frank; Moulin, Pierre; Brees, Dominique; Coleman, Bianca M; Mamo, Anna J; Garg, Abhishek V; Jaycox, Jillian R; Siebenlist, Ulrich; Kammüller, Michael; Gaffen, Sarah L

    2016-06-01

    Antibodies targeting IL-17A or its receptor, IL-17RA, are approved to treat psoriasis and are being evaluated for other autoimmune conditions. Conversely, IL-17 signaling is critical for immunity to opportunistic mucosal infections caused by the commensal fungus Candida albicans, as mice and humans lacking the IL-17R experience chronic mucosal candidiasis. IL-17A, IL-17F, and IL-17AF bind the IL-17RA-IL-17RC heterodimeric complex and deliver qualitatively similar signals through the adaptor Act1. Here, we used a mouse model of acute oropharyngeal candidiasis to assess the impact of blocking IL-17 family cytokines compared with specific IL-17 cytokine gene knockout mice. Anti-IL-17A antibodies, which neutralize IL-17A and IL-17AF, caused elevated oral fungal loads, whereas anti-IL-17AF and anti-IL-17F antibodies did not. Notably, there was a cooperative effect of blocking IL-17A, IL-17AF, and IL-17F together. Termination of anti-IL-17A treatment was associated with rapid C. albicans clearance. IL-17F-deficient mice were fully resistant to oropharyngeal candidiasis, consistent with antibody blockade. However, IL-17A-deficient mice had lower fungal burdens than anti-IL-17A-treated mice. Act1-deficient mice were much more susceptible to oropharyngeal candidiasis than anti-IL-17A antibody-treated mice, yet anti-IL-17A and anti-IL-17RA treatment caused equivalent susceptibilities. Based on microarray analyses of the oral mucosa during infection, only a limited number of genes were associated with oropharyngeal candidiasis susceptibility. In sum, we conclude that IL-17A is the main cytokine mediator of immunity in murine oropharyngeal candidiasis, but a cooperative relationship among IL-17A, IL-17AF, and IL-17F exists in vivo. Susceptibility displays the following hierarchy: IL-17RA- or Act1-deficiency > anti-IL-17A + anti-IL-17F antibodies > anti-IL-17A or anti-IL-17RA antibodies > IL-17A deficiency. © Society for Leukocyte Biology.

  8. Models for radiation-induced tissue degeneration and conceptualization of rehabilitation of irradiated tissue by cell therapy

    International Nuclear Information System (INIS)

    Phulpin, Berengere

    2011-01-01

    Radiation therapy induced acute and late sequelae within healthy tissue included in the irradiated area. In general, lesions are characterized by ischemia, cell apoptosis and fibrosis. In this context, cell therapy using bone marrow mesenchymal stem cells (BMSC) might represent an attractive new therapeutic approach, based partly on their angiogenic ability and their involvement in the natural processes of tissue repair. The first part of this work consisted in the development of experimental mouse model of radio-induced tissue degeneration similar to that occurring after radiotherapy. The aim was to better understand the physiopathological mechanisms of radiation-induced tissue damage and to determine the best treatment strategy. The second part of this work investigated the feasibility of autologous BMSC therapy on the murine model of radiation previously established with emphasis on two pre-requisites: the retention of the injected cells within the target tissue and the evaluation of the graft on bone metabolism. This preclinical investigation in a mouse model constitutes an essential step allowing an evaluation of the benefit of cell therapy for the treatment of radiation-induced tissue injury. Data from these studies could allow the proposal of clinical studies [fr

  9. Acute administration of n-3 rich triglyceride emulsions provides cardioprotection in murine models after ischemia-reperfusion.

    Science.gov (United States)

    Zirpoli, Hylde; Abdillahi, Mariane; Quadri, Nosirudeen; Ananthakrishnan, Radha; Wang, Lingjie; Rosario, Rosa; Zhu, Zhengbin; Deckelbaum, Richard J; Ramasamy, Ravichandran

    2015-01-01

    Dietary n-3 fatty acids (FAs) may reduce cardiovascular disease risk. We questioned whether acute administration of n-3 rich triglyceride (TG) emulsions could preserve cardiac function and decrease injury after ischemia/reperfusion (I/R) insult. We used two different experimental models: in vivo, C57BL/6 mice were exposed to acute occlusion of the left anterior descending coronary artery (LAD), and ex-vivo, C57BL/6 murine hearts were perfused using Langendorff technique (LT). In the LAD model, mice treated with n-3 TG emulsion (1.5 g/kg body weight), immediately after ischemia and 1 h later during reperfusion, significantly reduced infarct size and maintained cardiac function (plevels, as a marker of injury, were significantly reduced by n-3 TG emulsion. To investigate the mechanisms by which n-3 FAs protects hearts from I/R injury, we investigated changes in key pathways linked to cardioprotection. In the ex-vivo model, we showed that n-3 FAs increased phosphorylation of AKT and GSK3β proteins (plevel and reduced an autophagy marker, Beclin-1 (pGSK3β inhibitor plus n-3 TG significantly inhibited LDH release. We conclude that acute n-3 TG injection during reperfusion provides cardioprotection. This may prove to be a novel acute adjunctive reperfusion therapy after treating patients with myocardial infarction.

  10. Intravenous immunoglobulin prevents murine antibody-mediated acute lung injury at the level of neutrophil reactive oxygen species (ROS production.

    Directory of Open Access Journals (Sweden)

    John W Semple

    Full Text Available Transfusion-related acute lung injury (TRALI is a leading cause of transfusion-associated mortality that can occur with any type of transfusion and is thought to be primarily due to donor antibodies activating pulmonary neutrophils in recipients. Recently, a large prospective case controlled clinical study of cardiac surgery patients demonstrated that despite implementation of male donors, a high incidence of TRALI still occurred and suggested a need for additional interventions in susceptible patient populations. To examine if intravenous immunoglobulin (IVIg may be effective, a murine model of antibody-mediated acute lung injury that approximates human TRALI was examined. When BALB/c mice were injected with the anti-major histocompatibility complex class I antibody 34-1-2s, mild shock (reduced rectal temperature and respiratory distress (dyspnea were observed and pre-treatment of the mice with 2 g/kg IVIg completely prevented these symptoms. To determine IVIg's usefulness to affect severe lung damage, SCID mice, previously shown to be hypersensitive to 34-1-2s were used. SCID mice treated with 34-1-2s underwent severe shock, lung damage (increased wet/dry ratios and 40% mortality within 2 hours. Treatment with 2 g/kg IVIg 18 hours before 34-1-2s administration completely protected the mice from all adverse events. Treatment with IVIg after symptoms began also reduced lung damage and mortality. While the prophylactic IVIg administration did not affect 34-1-2s-induced pulmonary neutrophil accumulation, bone marrow-derived neutrophils from the IVIg-treated mice displayed no spontaneous ROS production nor could they be stimulated in vitro with fMLP or 34-1-2s. These results suggest that IVIg prevents murine antibody-mediated acute lung injury at the level of neutrophil ROS production and thus, alleviating tissue damage.

  11. Moderate acute intake of de-alcoholized red wine, but not alcohol, is protective against radiation-induced DNA damage ex vivo -- results of a comparative in vivo intervention study in younger men.

    Science.gov (United States)

    Greenrod, W; Stockley, C S; Burcham, P; Abbey, M; Fenech, M

    2005-12-11

    Moderate intake of wine is associated with reduced risk of cardiovascular disease and possibly cancer however it remains unclear whether the potential health benefits of wine intake are due to alcohol or the non-alcoholic fraction of wine. We therefore tested the hypothesis that the non-alcoholic fraction of wine protects against genome damage induced by oxidative stress in a crossover intervention study involving six young adult males aged 21-26 years. The participants adhered to a low plant phenolic compound diet for 48 h prior to consuming 300 mL of complete red wine, de-alcoholized red wine or ethanol on separate occasions 1 week apart. Blood samples were collected 0.5, 1.0 and 2.0 h after beverage consumption. Baseline and radiation-induced genome damage was measured using the cytokinesis-block micronucleus assay and total plasma catechin concentration was measured. Consumption of de-alcoholized red wine significantly decreased the gamma radiation-induced DNA damage at 1 and 2 h post-consumption by 20%. In contrast alcohol tended to increase radiation-induced genome damage and complete wine protected against radiation-induced genome damage relative to alcohol. The observed effects were only weakly correlated with the concentration of total plasma catechin (R=-0.23). These preliminary data suggest that only the non-alcoholic fraction of red wine protects DNA from oxidative damage but this effect cannot be explained solely by plasma catechin.

  12. Moderate acute intake of de-alcoholised red wine, but not alcohol, is protective against radiation-induced DNA damage ex vivo-Results of a comparative in vivo intervention study in younger men

    Energy Technology Data Exchange (ETDEWEB)

    Greenrod, W. [CSIRO Health Sciences and Nutrition, Genome Health and Nutrigenomics Laboratory, PO Box 10041, Adelaide BC, SA 5000 (Australia); Department of Clinical and Experimental Pharmacology, University of Adelaide, South Australia (Australia); Stockley, C.S. [Australian Wine Research Institute, South Australia (Australia); Burcham, P. [Department of Clinical and Experimental Pharmacology, University of Adelaide, South Australia (Australia); Abbey, M. [CSIRO Health Sciences and Nutrition, Genome Health and Nutrigenomics Laboratory, PO Box 10041, Adelaide BC, SA 5000 (Australia); Fenech, M. [CSIRO Health Sciences and Nutrition, Genome Health and Nutrigenomics Laboratory, PO Box 10041, Adelaide BC, SA 5000 (Australia)]. E-mail: michael.fenech@hsn.csiro.au

    2005-12-11

    Moderate intake of wine is associated with reduced risk of cardiovascular disease and possibly cancer however it remains unclear whether the potential health benefits of wine intake are due to alcohol or the non-alcoholic fraction of wine. We therefore tested the hypothesis that the non-alcoholic fraction of wine protects against genome damage induced by oxidative stress in a crossover intervention study involving six young adult males aged 21-26 years. The participants adhered to a low plant phenolic compound diet for 48 h prior to consuming 300 mL of complete red wine, dealcoholised red wine or ethanol on separate occasions 1 week apart. Blood samples were collected 0.5, 1.0 and 2.0 h after beverage consumption. Baseline and radiation-induced genome damage was measured using the cytokinesis-block micronucleus assay and total plasma catechin concentration was measured. Consumption of dealcoholised red wine significantly decreased the gamma radiation-induced DNA damage at 1 and 2 h post-consumption by 20%. In contrast alcohol tended to increase radiation-induced genome damage and complete wine protected against radiation-induced genome damage relative to alcohol. The observed effects were only weakly correlated with the concentration of total plasma catechin (R = -0.23). These preliminary data suggest that only the non-alcoholic fraction of red wine protects DNA from oxidative damage but this effect cannot be explained solely by plasma catechin.

  13. Moderate acute intake of de-alcoholised red wine, but not alcohol, is protective against radiation-induced DNA damage ex vivo-Results of a comparative in vivo intervention study in younger men

    International Nuclear Information System (INIS)

    Greenrod, W.; Stockley, C.S.; Burcham, P.; Abbey, M.; Fenech, M.

    2005-01-01

    Moderate intake of wine is associated with reduced risk of cardiovascular disease and possibly cancer however it remains unclear whether the potential health benefits of wine intake are due to alcohol or the non-alcoholic fraction of wine. We therefore tested the hypothesis that the non-alcoholic fraction of wine protects against genome damage induced by oxidative stress in a crossover intervention study involving six young adult males aged 21-26 years. The participants adhered to a low plant phenolic compound diet for 48 h prior to consuming 300 mL of complete red wine, dealcoholised red wine or ethanol on separate occasions 1 week apart. Blood samples were collected 0.5, 1.0 and 2.0 h after beverage consumption. Baseline and radiation-induced genome damage was measured using the cytokinesis-block micronucleus assay and total plasma catechin concentration was measured. Consumption of dealcoholised red wine significantly decreased the gamma radiation-induced DNA damage at 1 and 2 h post-consumption by 20%. In contrast alcohol tended to increase radiation-induced genome damage and complete wine protected against radiation-induced genome damage relative to alcohol. The observed effects were only weakly correlated with the concentration of total plasma catechin (R = -0.23). These preliminary data suggest that only the non-alcoholic fraction of red wine protects DNA from oxidative damage but this effect cannot be explained solely by plasma catechin

  14. Acute administration of n-3 rich triglyceride emulsions provides cardioprotection in murine models after ischemia-reperfusion.

    Directory of Open Access Journals (Sweden)

    Hylde Zirpoli

    Full Text Available Dietary n-3 fatty acids (FAs may reduce cardiovascular disease risk. We questioned whether acute administration of n-3 rich triglyceride (TG emulsions could preserve cardiac function and decrease injury after ischemia/reperfusion (I/R insult. We used two different experimental models: in vivo, C57BL/6 mice were exposed to acute occlusion of the left anterior descending coronary artery (LAD, and ex-vivo, C57BL/6 murine hearts were perfused using Langendorff technique (LT. In the LAD model, mice treated with n-3 TG emulsion (1.5 g/kg body weight, immediately after ischemia and 1 h later during reperfusion, significantly reduced infarct size and maintained cardiac function (p<0.05. In the LT model, administration of n-3 TG emulsion (300 mg TG/100 ml during reperfusion significantly improved functional recovery (p<0.05. In both models, lactate dehydrogenase (LDH levels, as a marker of injury, were significantly reduced by n-3 TG emulsion. To investigate the mechanisms by which n-3 FAs protects hearts from I/R injury, we investigated changes in key pathways linked to cardioprotection. In the ex-vivo model, we showed that n-3 FAs increased phosphorylation of AKT and GSK3β proteins (p<0.05. Acute n-3 TG emulsion treatment also increased Bcl-2 protein level and reduced an autophagy marker, Beclin-1 (p<0.05. Additionally, cardioprotection by n-3 TG emulsion was linked to changes in PPARγ protein expression (p<0.05. Rosiglitazone and p-AKT inhibitor counteracted the positive effect of n-3 TG; GSK3β inhibitor plus n-3 TG significantly inhibited LDH release. We conclude that acute n-3 TG injection during reperfusion provides cardioprotection. This may prove to be a novel acute adjunctive reperfusion therapy after treating patients with myocardial infarction.

  15. Radiation-induced thermoacoustic imaging

    International Nuclear Information System (INIS)

    Bowen, T.

    1984-01-01

    This invention provides a new technique for obtaining information non-invasively on the composition and structures of a material or body by detecting radiation-induced thermoacoustic image features. This is accomplished by utilizing the acoustic wave generated by sudden thermal stress. The sudden thermal stress is induced by a pulse of radiation which deposits energy causing a rapid, but very small, rise of temperature (typically, ΔT approximately 10sup(-6) - 10sup(-5) deg C). The radiation may be ionizing radiation, such as high energy electrons, photons (x-rays), neutrons, or other charged particles or it may be non-ionizing radiation, such as R.F. and microwave electromagnetic radiation and ultrasonic radiation. The choice of radiation depends on the nature of the body to be imaged and the type of information desired

  16. In vivo T2* weighted MRI visualizes cardiac lesions in murine models of acute and chronic viral myocarditis.

    Directory of Open Access Journals (Sweden)

    Xavier Helluy

    Full Text Available Acute and chronic forms of myocarditis are mainly induced by virus infections. As a consequence of myocardial damage and inflammation dilated cardiomyopathy and chronic heart failure may develop. The gold standard for the diagnosis of myocarditis is endomyocardial biopsies which are required to determine the etiopathogenesis of cardiac inflammatory processes. However, new non-invasive MRI techniques hold great potential in visualizing cardiac non-ischemic inflammatory lesions at high spatial resolution, which could improve the investigation of the pathophysiology of viral myocarditis.Here we present the discovery of a novel endogenous T2* MRI contrast of myocardial lesions in murine models of acute and chronic CVB3 myocarditis. The evaluation of infected hearts ex vivo and in vivo by 3D T2w and T2*w MRI allowed direct localization of virus-induced myocardial lesions without any MRI tracer or contrast agent. T2*w weighted MRI is able to detect both small cardiac lesions of acute myocarditis and larger necrotic areas at later stages of chronic myocarditis, which was confirmed by spatial correlation of MRI hypointensity in myocardium with myocardial lesions histologically. Additional in vivo and ex vivo MRI analysis proved that the contrast mechanism was due to a strong paramagnetic tissue alteration in the vicinity of myocardial lesions, effectively pointing towards iron deposits as the primary contributor of contrast. The evaluation of the biological origin of the MR contrast by specific histological staining and transmission electron microscopy revealed that impaired iron metabolism primarily in mitochondria caused iron deposits within necrotic myocytes, which induces strong magnetic susceptibility in myocardial lesions and results in strong T2* contrast.This T2*w MRI technique provides a fast and sensitive diagnostic tool to determine the patterns and the severity of acute and chronic enteroviral myocarditis and the precise localization of

  17. In vivo T2* weighted MRI visualizes cardiac lesions in murine models of acute and chronic viral myocarditis

    Science.gov (United States)

    Helluy, Xavier; Sauter, Martina; Ye, Yu-Xiang; Lykowsky, Gunthard; Kreutner, Jakob; Yilmaz, Ali; Jahns, Roland; Boivin, Valerie; Kandolf, Reinhard; Jakob, Peter M.; Hiller, Karl-Heinz; Klingel, Karin

    2017-01-01

    Objective Acute and chronic forms of myocarditis are mainly induced by virus infections. As a consequence of myocardial damage and inflammation dilated cardiomyopathy and chronic heart failure may develop. The gold standard for the diagnosis of myocarditis is endomyocardial biopsies which are required to determine the etiopathogenesis of cardiac inflammatory processes. However, new non-invasive MRI techniques hold great potential in visualizing cardiac non-ischemic inflammatory lesions at high spatial resolution, which could improve the investigation of the pathophysiology of viral myocarditis. Results Here we present the discovery of a novel endogenous T2* MRI contrast of myocardial lesions in murine models of acute and chronic CVB3 myocarditis. The evaluation of infected hearts ex vivo and in vivo by 3D T2w and T2*w MRI allowed direct localization of virus-induced myocardial lesions without any MRI tracer or contrast agent. T2*w weighted MRI is able to detect both small cardiac lesions of acute myocarditis and larger necrotic areas at later stages of chronic myocarditis, which was confirmed by spatial correlation of MRI hypointensity in myocardium with myocardial lesions histologically. Additional in vivo and ex vivo MRI analysis proved that the contrast mechanism was due to a strong paramagnetic tissue alteration in the vicinity of myocardial lesions, effectively pointing towards iron deposits as the primary contributor of contrast. The evaluation of the biological origin of the MR contrast by specific histological staining and transmission electron microscopy revealed that impaired iron metabolism primarily in mitochondria caused iron deposits within necrotic myocytes, which induces strong magnetic susceptibility in myocardial lesions and results in strong T2* contrast. Conclusion This T2*w MRI technique provides a fast and sensitive diagnostic tool to determine the patterns and the severity of acute and chronic enteroviral myocarditis and the precise

  18. Spontaneous and radiation-induced leukemogenesis of the mouse small eye mutant, Pax6Sey3H

    International Nuclear Information System (INIS)

    Nitta, Yumiko; Satoh, Kenichi; Yoshida, Kazuko; Senba, Kei; Nakagata, Naomi; Peters, J.; Cattanach, B.M.

    2004-01-01

    Allelic loss on the chromosome 2 is associated with radiation-induced murine acute myeloid leukemia. However, the gene, which contributes mainly to the leukemogenesis has not yet been identified. Expecting any predisposition to acute myeloid leukemia, we performed a radiation leukemogenesis experiment with Pax6 SeY3H , one of the small eye mutants carrying a congenital hemizygosity of the chromosome 2 middle region. A deletion mapping of Pax6 SeY3H with 50 sequence-tagged site (STS) markers indicated that the deleted segment extended between the 106.00 and 111.47 Mb site from the centromere with a length of 5.47 Mb. In the deleted segment, 6 known and 17 novel genes were located. Pax6 SeY3H mutants that crossed back into C3H/He did not develop myeloid leukemia spontaneously, but they did when exposed to gamma-rays. The final incidence of myeloid leukemia in mutants (25.8%) was as high as that in normal sibs (21.4%). Survival curves of leukemia-bearing mutants shifted toward the left (p=0.043 by the Log rank test). F1 hybrids of Pax6 SeY3H with JF1 were less susceptible to radiation than Pax6 SeY3H onto C3H/He in regard to survival (p=0.003 and p<0.00001 for mutants and normal sibs, respectively, by a test of the difference between two proportions). Congenital deletion of the 5.47 Mb segment at the middle region on chromosome 2 alone did not trigger myeloid stem cells to expand clonally in vivo; however, the deletion shortcut the latency of radiation-induced myeloid leukemia. (author)

  19. Radiation induced sulfur dioxide removal

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    2000-01-01

    The biggest source of air pollution is the combustion of fossil fuels, were pollutants such as particulate, sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), and volatile organic compounds (VOC) are emitted. Among these pollutants, sulfur dioxide plays the main role in acidification of the environment. The mechanism of sulfur dioxide transformation in the environment is partly photochemical. This is not direct photooxidation, however, but oxidation through formed radicals. Heterogenic reactions play an important role in this transformation as well; therefore, observations from environmental chemistry can be used in air pollution control engineering. One of the most promising technologies for desulfurization of the flue gases (and simultaneous denitrification) is radiation technology with an electron accelerator application. Contrary to the nitrogen oxides (NO x ) removal processes, which is based on pure radiation induced reactions, sulfur dioxide removal depends on two pathways: a thermochemical reaction in the presence of ammonia/water vapor and a radiation set of radiochemical reactions. The mechanism of these reactions and the consequent technological parameters of the process are discussed in this paper. The industrial application of this radiation technology is being implemented in an industrial pilot plant operated by INCT at EPS Kaweczyn. A full-scale industrial plant is currently in operation in China, and two others are under development in Japan and Poland. (author)

  20. Radiation-induced instability of human genome

    International Nuclear Information System (INIS)

    Ryabchenko, N.N.; Demina, Eh.A.

    2014-01-01

    A brief review is dedicated to the phenomenon of radiation-induced genomic instability where the increased level of genomic changes in the offspring of irradiated cells is characteristic. Particular attention is paid to the problems of genomic instability induced by the low-dose radiation, role of the bystander effect in formation of radiation-induced instability, and its relationship with individual radiosensitivity. We believe that in accordance with the paradigm of modern radiobiology the increased human individual radiosensitivity can be formed due to the genome instability onset and is a significant risk factor for radiation-induced cancer

  1. Radiation-Induced Differentiation in Human Lung Fibroblast

    International Nuclear Information System (INIS)

    Park, Sa-Rah; Ahn, Ji-Yeon; Han, Young-Soo; Shim, Jie-Young; Yun, Yeon-Sook; Song, Jie-Young

    2007-01-01

    One of the most common tumors in many countries is lung cancer and patients with lung cancer may take radiotherapy. Although radiotherapy may have its own advantages, it can also induce serious problems such as acute radiation pneumonitis and pulmonary fibrosis. Pulmonary fibrosis is characterized by excessive production of α-SMA and accumulation of extracellular matrix (ECM) such as collagen and fibronectin. There has been a great amount of research about fibrosis but the exact mechanism causing the reaction is not elucidated especially in radiation-induced fibrosis. Until now it has been known that several factors such as transforming growth factor (TGF-β), tumor necrosis factor (TNF), interleukin (IL)-1, IL-6, platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) are related to fibrosis. Among them TGF-β with Smad signaling is known to be the main stream and other signaling molecules such as MAPK, ERK and JNK (3) also participates in the process. In addition to those above factors, it is thought that more diverse and complicate mechanisms may involve in the radiationinduced fibrosis. Therefore, to investigate the underlying mechanisms in radiation induced fibrosis, first of all, we confirmed whether radiation induces trans differentiation in human normal lung fibroblasts. Here, we suggest that not only TGF-β but also radiation can induce trans differentiation in human lung fibroblast WI-38 and IMR-90

  2. Mechanisms of decreased intestinal epithelial proliferation and increased apoptosis in murine acute lung injury.

    Science.gov (United States)

    Husain, Kareem D; Stromberg, Paul E; Woolsey, Cheryl A; Turnbull, Isaiah R; Dunne, W Michael; Javadi, Pardis; Buchman, Timothy G; Karl, Irene E; Hotchkiss, Richard S; Coopersmith, Craig M

    2005-10-01

    The aim of this study was to determine the effects of acute lung injury on the gut epithelium and examine mechanisms underlying changes in crypt proliferation and apoptosis. The relationship between severity and timing of lung injury to intestinal pathology was also examined. Randomized, controlled study. University research laboratory. Genetically inbred mice. Following induction of acute lung injury, gut epithelial proliferation and apoptosis were assessed in a) C3H/HeN wild-type and C3H/HeJ mice, which lack functional Toll-like receptor 4 (n = 17); b) C57Bl/6 mice that received monoclonal anti-tumor necrosis factor-alpha or control antibody (n = 22); and c) C57Bl/6 wild-type and transgenic mice that overexpress Bcl-2 in their gut epithelium (n = 21). Intestinal epithelial proliferation and death were also examined in animals with differing degrees of lung inflammation (n = 24) as well as in a time course analysis following a fixed injury (n = 18). Acute lung injury caused decreased proliferation and increased apoptosis in crypt epithelial cells in all animals studied. C3H/HeJ mice had higher levels of proliferation than C3H/HeN animals without additional changes in apoptosis. Anti-tumor necrosis factor-alpha antibody had no effect on gut epithelial proliferation or death. Overexpression of Bcl-2 did not change proliferation despite decreasing gut apoptosis. Proliferation and apoptosis were not correlated to severity of lung injury, as gut alterations were lost in mice with more severe acute lung injury. Changes in both gut epithelial proliferation and death were apparent within 12 hrs, but proliferation was decreased 36 hrs following acute lung injury while apoptosis returned to normal. Acute lung injury causes disparate effects on crypt proliferation and apoptosis, which occur, at least in part, through differing mechanisms involving Toll-like receptor 4 and Bcl-2. Severity of lung injury does not correlate with perturbations in proliferation or death in the

  3. Better flocculants by radiation induced polymerization

    International Nuclear Information System (INIS)

    Laizier, J.; Gaussens, G.

    1978-01-01

    The use of radiation induced polymerization should theoritically allow to prepare better flocculants. The testings of several products prepared by such a process shows that better properties are indeed obtained: better efficiencies, lower amounts needed, better overall properties [fr

  4. Contribution of radiation-induced, nitric oxide-mediated bystander effect to radiation-induced adaptive response.

    Science.gov (United States)

    Matsumoto, H.; Ohnishi, T.

    There has been a recent upsurge of interest in radiation-induced adaptive response and bystander effect which are specific modes in stress response to low-dose low-dose rate radiation Recently we found that the accumulation of inducible nitric oxide NO synthase iNOS in wt p53 cells was induced by chronic irradiation with gamma rays followed by acute irradiation with X-rays but not by each one resulting in an increase in nitrite concentrations of medium It is suggested that the accumulation of iNOS may be due to the depression of acute irradiation-induced p53 functions by pre-chronic irradiation In addition we found that the radiosensitivity of wt p53 cells against acute irradiation with X-rays was reduced after chronic irradiation with gamma rays This reduction of radiosensitivity of wt p53 cells was nearly completely suppressed by the addition of NO scavenger carboxy-PTIO to the medium This reduction of radiosensitivity of wt p53 cells is just radiation-induced adaptive response suggesting that NO-mediated bystander effect may considerably contribute to adaptive response induced by radiation

  5. Influence of Acute High Glucose on Protein Abundance Changes in Murine Glomerular Mesangial Cells

    Directory of Open Access Journals (Sweden)

    Michelle T. Barati

    2016-01-01

    Full Text Available The effects of acute exposure to high glucose levels as experienced by glomerular mesangial cells in postprandial conditions and states such as in prediabetes were investigated using proteomic methods. Two-dimensional gel electrophoresis and matrix assisted laser desorption ionization time of flight mass spectrometry methods were used to identify protein expression patterns in immortalized rat mesangial cells altered by 2 h high glucose (HG growth conditions as compared to isoosmotic/normal glucose control (NG⁎ conditions. Unique protein expression changes at 2 h HG treatment were measured for 51 protein spots. These proteins could be broadly grouped into two categories: (1 proteins involved in cell survival/cell signaling and (2 proteins involved in stress response. Immunoblot experiments for a protein belonging to both categories, prohibitin (PHB, supported a trend for increased total expression as well as significant increases in an acidic PHB isoform. Additional studies confirmed the regulation of proteasomal subunit alpha-type 2 and the endoplasmic reticulum chaperone and oxidoreductase PDI (protein disulfide isomerase, suggesting altered ER protein folding capacity and proteasomal function in response to acute HG. We conclude that short term high glucose induces subtle changes in protein abundances suggesting posttranslational modifications and regulation of pathways involved in proteostasis.

  6. Safety and efficacy of the immunosuppressive agent 6-tioguanine in murine model of acute and chronic colitis

    Directory of Open Access Journals (Sweden)

    van Bodegraven Adriaan A

    2011-05-01

    Full Text Available Abstract Background Oral thiopurines are effective and widely used in treatment of inflammatory bowel disease (IBD in humans, although their use is limited due the development of adverse events. Here, we examine the efficacy and toxicity of oral treatment with 6-tioguanine (6-TG and azathioprine (AZA in a murine model of IBD. Methods We induced acute or chronic colitis in BALB/c mice by one or four cycles of 3% dextran sulphate sodium (DSS, respectively. Mice were treated by daily gavages of various dosages of 6-tioguanine, azathioprine, or by phosphate buffered saline (PBS starting the first day of DSS or after two cycles of DSS, respectively. We monitored the efficacy and toxicity by measuring the weight change and serum alanine aminotransferase (ALT activity and by disease severity and histology, at the end of the experiment. Moreover, we measured cytokine production after colon fragment cultivation by enzyme-linked immunoabsorbent assay and numbers of apoptotic cells in the spleen by flow cytometry. Results 6-TG is effective in the treatment of acute DSS-induced colitis in a dose-dependent manner and 40 μg of 6-TG is significantly more effective in the treatment of acute colitis than both AZA and PBS. This effect is accompanied by decrease of IL-6 and IFN-γ production in colon. We did not observe histological abnormalities in liver samples from control (PBS or 6-TG treated mice. However, liver samples from most mice treated with AZA showed mild, yet distinct signs of hepatotoxicity. In chronic colitis, all thiopurine derivatives improved colitis, 20 μg of 6-TG per dose was superior. High doses of 6-TG led to significant weight loss at the end of the therapy, but none of the thiopurine derivatives increased levels of serum ALT. Both thiopurine derivatives reduced the proportion of apoptotic T helper cells, but a high production of both IL-6 and TGF-β was observed only in colon of AZA-treated mice. Conclusions Use of 6-TG in the treatment

  7. PAI-1-dependent endothelial cell death determines severity of radiation-induced intestinal injury.

    Directory of Open Access Journals (Sweden)

    Rym Abderrahmani

    Full Text Available Normal tissue toxicity still remains a dose-limiting factor in clinical radiation therapy. Recently, plasminogen activator inhibitor type 1 (SERPINE1/PAI-1 was reported as an essential mediator of late radiation-induced intestinal injury. However, it is not clear whether PAI-1 plays a role in acute radiation-induced intestinal damage and we hypothesized that PAI-1 may play a role in the endothelium radiosensitivity. In vivo, in a model of radiation enteropathy in PAI-1 -/- mice, apoptosis of radiosensitive compartments, epithelial and microvascular endothelium was quantified. In vitro, the role of PAI-1 in the radiation-induced endothelial cells (ECs death was investigated. The level of apoptotic ECs is lower in PAI-1 -/- compared with Wt mice after irradiation. This is associated with a conserved microvascular density and consequently with a better mucosal integrity in PAI-1 -/- mice. In vitro, irradiation rapidly stimulates PAI-1 expression in ECs and radiation sensitivity is increased in ECs that stably overexpress PAI-1, whereas PAI-1 knockdown increases EC survival after irradiation. Moreover, ECs prepared from PAI-1 -/- mice are more resistant to radiation-induced cell death than Wt ECs and this is associated with activation of the Akt pathway. This study demonstrates that PAI-1 plays a key role in radiation-induced EC death in the intestine and suggests that this contributes strongly to the progression of radiation-induced intestinal injury.

  8. 3 cases of radiation-induced sarcoma

    International Nuclear Information System (INIS)

    Shiba, Keiichiro; Fukuma, Hisatoshi; Beppu, Yasuo; Hirota, Teruyuki; Shinohara, Norio.

    1982-01-01

    Criteria for the diagnosis of radiation-induced sarcoma have been previously described. All cases must have a history of irradiation and the second neoplasm must have arisen in the area of the radiation field. A latent period of several years must have elapsed after irradiation before clinical evidence of a second malignant neoplasm. Most important thing is that, all suspected cases must have been proved histologically. We have experienced 3 cases of radiation-induced sarcoma, they were 42-years-old man who developed an osteosarcoma of the lumbar spine at the field of postoperative irradiation for seminoma 7 years previously, 69-years-old woman who developed a malignant fibrous histiocytoma of the buttock at the field of radical radiation for uterine carcinoma 7 years previously and 59-years-old woman who developed an extraskeletal osteosarcoma of the abdominal wall at the field of postoperative irradiation for uterine sarcoma 7 years previously. The last case is very rare and only 8 cases of radiation-induced extraskeletal osteosarcoma have been reported. Since there has been a definite trend in the treatment of cancer toward employing radiation for more favorable cases, in addition to technical improvements in the administration of radiotherapy and more modern equipment, survival data may have been altered considerably in many malignant tumors. Accordingly, more radiation-induced tumors may be encountered in the future. The clinical presentation and histopathology of these radiation-induced sarcomas are presented with a review of the literature. (author)

  9. Radiation-induced centers in inorganic glasses

    International Nuclear Information System (INIS)

    Brekhovskikh, S.M.; Tyul'nin, V.A.

    1988-01-01

    The nature, structure and formation mechanisms of radiation-induced colour centers, EPR, luminescence, generated ionizing radiation in nonorganic oxide glasses are considered. Experimental material covering both fundamental aspects of radiation physics and glass chemistry, and aspects intimately connected with the creation of new materials with the given radiation-spectral characteristics, with possibilities to prepare radiation-stable and radiation-sensitive glasses is systematized and generalized. Considerable attention is paid to the detection of radiation-induced center binding with composition, glass structures redox conditions for their synthesis. Some new possibilities of practical application of glasses with radiation-induced centers, in particular, to record optical information are reflected in the paper

  10. MRI-based assessment of liver perfusion and hepatocyte injury in the murine model of acute hepatitis.

    Science.gov (United States)

    Byk, Katarzyna; Jasinski, Krzysztof; Bartel, Zaneta; Jasztal, Agnieszka; Sitek, Barbara; Tomanek, Boguslaw; Chlopicki, Stefan; Skorka, Tomasz

    2016-12-01

    To assess alterations in perfusion and liver function in the concanavalin A (ConA)-induced mouse model of acute liver failure (ALF) using two magnetic resonance imaging (MRI)-based methods: dynamic contrast-enhanced MRI (DCE-MRI) with Gd-EOB-DTPA contrast agent and arterial spin labelling (ASL). BALB/c mice were studied using a 9.4 T MRI system. The IntraGateFLASH TM and FAIR-EPI pulse sequences were used for optimum mouse abdomen imaging. The average perfusion values for the liver of the control and ConA group were equal to 245 ± 20 and 200 ± 32 ml/min/100 g (p = 0.008, respectively). DCE-MRI showed that the time to the peak of the image enhancement was 6.14 ± 1.07 min and 9.72 ± 1.69 min in the control and ConA group (p < 0.001, respectively), while the rate of the contrast wash-out in the control and ConA group was 0.037 ± 0.008 and 0.021 ± 0.008 min -1 (p = 0.004, respectively). These results were consistent with hepatocyte injury in the ConA-treated mice as confirmed by histopathological staining. Both the ASL and DCE-MRI techniques represent a reliable methodology to assess alterations in liver perfusion and hepatocyte integrity in murine hepatitis.

  11. Radiation-induced heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Stroobandt, R; Knieriem, H J; De Wolf, L; Joossens, J V

    1975-01-01

    A 45-year old woman underwent a radical mastectomy in 1965 for carcinoma of the left breast with metastasis in the left axillar lymph nodes. Fifty per cent of the heart received 4,000 rads during postoperative X-ray therapy. Patient developed radiopneumonia and symptoms of acute pericarditis in 1967. Constrictive pericarditis developed gradually from 1972 on. A pericardiectomy was performed in June 1974 and a thickened pericardium could be removed. Light and electron microscopic examination of a surgical biopsy of the left ventricular epi-myocardium revealed epicardial fibrosis, interstitial fibrosis of the myocardium and perivascular fibrosis. The diagnosis of post-radiation pericarditis was made. The myocardial involvement may be responsible for the subsequent clinical course.

  12. Radiation-induced linking reactions in polyethylene

    International Nuclear Information System (INIS)

    Zoepfl, F.J.

    1983-01-01

    Three types of measurements are reported relating to chemical reactions in polyethylene induced by ionizing radiation: 1) viscometric and low-angle laser light scattering measurements to determine the effect of a radical scavenger on the yield of links; 2) calorimetric measurements to determine the effect of radiation-induced linking on the melting behavior of polyethylene; and 3) high-resolution solution carbon 13 nuclear magnetic resonance (NMR) spectrometry measurements to determine the nature of the links and the method of their formation. The NMR results present the first direct detection of radiation-induced long-chain branching (Y links) in polyethylene, and place an apparent upper limit on the yield of H-shaped crosslinks that are formed when polyethylene is irradiated to low absorbed doses. The effect of radiation-induced linking on the melting behavior of polyethylene was examined using differential scanning calorimetry (DSC). It was found that radiation-induced links do not change the heat of fusion of polythylene crystals, but decrease the melt entropy and increase the fold surface free energy per unit area of the crystals. The carbon 13 NMR results demonstrate that long-chain branches (Y links) are formed much more frequently than H-shaped crosslinks at low absorbed doses. The Y links are produced by reactions of alkyl free radicals with terminal vinyl groups in polyethylene

  13. Mechanisms of transient radiation-induced creep

    International Nuclear Information System (INIS)

    Pyatiletov, Yu.S.

    1981-01-01

    Radiation-induced creep at the transient stage is investigated for metals. The situation, when several possible creep mechanisms operate simultaneously is studied. Among them revealed are those which give the main contribution and determine thereby the creep behaviour. The time dependence of creep rate and its relation to the smelling rate is obtained. The results satisfactorily agree with the available experimental data [ru

  14. Reducing radiation induced emesis in abdominal radiotherapy

    International Nuclear Information System (INIS)

    Griffin, K.

    1994-01-01

    In patients with seminoma testes, a comparison was made between radiation induced emesis suffered by patients receiving 'dogleg' radiotherapy with those suffered by patients who received para-aortic radiotherapy. The same comparisons were made between the effects suffered by those patients who received the anti-emetic, Ondansetron, and those suffered by patients who received conventional anti-emetics. (UK)

  15. Sequential activation of proteases in radiation induced apoptosis

    International Nuclear Information System (INIS)

    Watters, D.; Waterhouse, N.

    1997-01-01

    Full text: Significant advances have been made in recent years in unraveling the molecular mechanisms of apoptosis particularly in relation to Fas- and TNF-mediated cell death, however there are considerable gaps in our knowledge of the processes involved in apoptosis induced by ionizing radiation. We have used the degradation of specific proteolytic targets in a pair of isogenic Burkitt's Iymphoma cells lines (BL30A, sensitive and BL30K resistant) to study the sequence of events in the execution of radiation-induced apoptosis. Fodrin can be cleaved to fragments of 150 kDa and 120 kDa. In the case of Fas-mediated apoptosis both cleavages are inhibited by the caspase inhibitor zVAD-fmk at 10 μM, a concentration which inhibits all the hallmarks of apoptosis. However in radiation-induced apoptosis, inhibition of the clevage of fodrin to the 150 kDa fragment requires 100 μM zVAD-fink while apoptosis itself is inhibited at 10 μM. This suggests that different enzymes are responsible for the generation of the 150 kDa fragment in the two models of apoptosis. Fodrin has been reported to be cleaved by μ-calpain to a 150 kDa fragment however, the involvement of μ-calpain in apoptosis has not yet been established. In murine fodrin there is a caspase cleavage site within 1 kDa of the calpain cleavage site. In vitro studies using purified enzymes showed that only caspase-3 and μ-calpain could cleave fodrin in untreated cell extracts to the same sized fragments as seen during apoptosis in vivo. We provide evidence for the early activation of μ-calpain after ionizing radiation in the sensitive BL30A cell line, and show that the time course of μ-calpain activation parallels that of the appearance of the 150 kDa fragment. Caspase-3 is activated much later and is likely to be responsible for the generation of the 120 kDa fragment. μ-Calpain was not activated in the resistant cell line. Based on these results we propose a model for the proteolytic cascade in radiation-induced

  16. Allopurinol gel mitigates radiation-induced mucositis and dermatitis

    International Nuclear Information System (INIS)

    Kitagawa, Junichi; Nasu, Masanori; Okumura, Hayato; Matsumoto, Shigeji; Shibata, Akihiko; Makino, Kimiko; Terada, Hiroshi

    2008-01-01

    It has not been verified whether allopurinol application is beneficial in decreasing the severity of radiation-induced oral mucositis and dermatitis. Rats were divided into 4 groups and received 15 Gy irradiation on the left whisker pad. Group 1 received only irradiation. Group 2 was maintained by applying allopurinol/carrageenan-mixed gel (allopurinol gel) continuously from 2 days before to 20 days after irradiation. Group 3 had allopurinol gel applied for 20 days after radiation. Group 4 was maintained by applying carrageenan gel continuously from 2 days before to 20 days after irradiation. The intra oral mucosal and acute skin reactions were assessed daily using mucositis and skin score systems. The escape thresholds for mechanical stimulation to the left whisker pad were measured daily. In addition, the irradiated tissues at the endpoint of this study were compared with naive tissue. Escape threshold in group 2 was significantly higher than that in group 1, and mucositis and skin scores were much improved compared with those of group 1. Concerning escape threshold, mucositis and skin scores in group 3 began to improve 10 days after irradiation. Group 4 showed severe symptoms of mucositis and dermatitis to the same extent as that observed in group 1. In the histopathological study, the tissues of group 1 showed severe inflammatory reactions, compared with those of group 2. These results suggest that allopurinol gel application can mitigate inflammation reactions associated with radiation-induced oral mucositis and dermatitis. (author)

  17. ROS Mediates Radiation-Induced Differentiation in Human Lung Fibroblast

    International Nuclear Information System (INIS)

    Park, Sa Rah; Ahn, Ji Yeon; Kim, Mi Hyeung; Lim, Min Jin; Yun, Yeon Sook; Song, Jie Young

    2009-01-01

    One of the most common tumors worldwide is lung cancer and the number of patients with lung cancer received radiotherapy is increasing rapidly. Although radiotherapy may have lots of advantages, it can also induce serious adverse effects such as acute radiation pneumonitis and pulmonary fibrosis. Pulmonary fibrosis is characterized by excessive production of smooth muscle actin-alpha (a-SMA) and accumulation of extracellular matrix (ECM) such as collagen and fibronectin. There has been a great amount of research about fibrosis but the exact mechanism causing the reaction is not elucidated especially in radiation-induced fibrosis. Until now it has been known that several factors such as transforming growth factor (TGF-b), tumor necrosis factor (TNF), IL-6, platelet-derived growth factor (PDGF) and reactive oxygen species are related to fibrosis. It is also reported that reactive oxygen species (ROS) can be induced by radiation and can act as a second messenger in various signaling pathways. Therefore we focused on the role of ROS in radiation induced fibrosis. Here, we suggest that irradiation generate ROS mainly through NOX4, result in differentiation of lung fibroblast into myofibroblast

  18. Changes in peroxidases associated with radiation-induced sprout inhibition in garlic (Allium sativum L.)

    International Nuclear Information System (INIS)

    Croci, C.A.; Curvetto, N.R.; Orioli, G.A.; Arguello, J.A.

    1991-01-01

    The effects of an acute dose of γ-rays (10 Gy) to post-dormant garlic cloves on inner sprout growth and changes in peroxidases and soluble proteins were evaluated up to 100 days of storage in darkness at 19±1 0 C and 42±2% relative humidity. Radiation-induced inhibition of sprout growth became evident after 25 days of treatment and was synchronous with a marked increase in peroxidase activity. Thin-layer isoelectric focusing revealed that radiation induced an increase in the number of anodic peroxidase isoenzymes at 100 days, suggesting modifications in the vascularization process. Neither the soluble protein content nor the protein pattern were affected by irradiation. These results are discussed in terms of a possible mediating effect of peroxidase on radiation-induced sprout inhibition in garlic. (author)

  19. Changes in peroxidases associated with radiation-induced sprout inhibition in garlic (Allium sativum L. )

    Energy Technology Data Exchange (ETDEWEB)

    Croci, C.A.; Curvetto, N.R.; Orioli, G.A. (Universidad Nacional del Sur, Bahia Blanca (Argentina)); Arguello, J.A. (Universidad Nacional de Cordoba (Argentina). Dept. de Biologia Aplicada)

    1991-02-01

    The effects of an acute dose of {gamma}-rays (10 Gy) to post-dormant garlic cloves on inner sprout growth and changes in peroxidases and soluble proteins were evaluated up to 100 days of storage in darkness at 19+-1{sup 0}C and 42+-2% relative humidity. Radiation-induced inhibition of sprout growth became evident after 25 days of treatment and was synchronous with a marked increase in peroxidase activity. Thin-layer isoelectric focusing revealed that radiation induced an increase in the number of anodic peroxidase isoenzymes at 100 days, suggesting modifications in the vascularization process. Neither the soluble protein content nor the protein pattern were affected by irradiation. These results are discussed in terms of a possible mediating effect of peroxidase on radiation-induced sprout inhibition in garlic. (author).

  20. Receptor for advanced glycation end-products and World Trade Center particulate induced lung function loss: A case-cohort study and murine model of acute particulate exposure.

    Science.gov (United States)

    Caraher, Erin J; Kwon, Sophia; Haider, Syed H; Crowley, George; Lee, Audrey; Ebrahim, Minah; Zhang, Liqun; Chen, Lung-Chi; Gordon, Terry; Liu, Mengling; Prezant, David J; Schmidt, Ann Marie; Nolan, Anna

    2017-01-01

    World Trade Center-particulate matter(WTC-PM) exposure and metabolic-risk are associated with WTC-Lung Injury(WTC-LI). The receptor for advanced glycation end-products (RAGE) is most highly expressed in the lung, mediates metabolic risk, and single-nucleotide polymorphisms at the AGER-locus predict forced expiratory volume(FEV). Our objectives were to test the hypotheses that RAGE is a biomarker of WTC-LI in the FDNY-cohort and that loss of RAGE in a murine model would protect against acute PM-induced lung disease. We know from previous work that early intense exposure at the time of the WTC collapse was most predictive of WTC-LI therefore we utilized a murine model of intense acute PM-exposure to determine if loss of RAGE is protective and to identify signaling/cytokine intermediates. This study builds on a continuing effort to identify serum biomarkers that predict the development of WTC-LI. A case-cohort design was used to analyze a focused cohort of male never-smokers with normal pre-9/11 lung function. Odds of developing WTC-LI increased by 1.2, 1.8 and 1.0 in firefighters with soluble RAGE (sRAGE)≥97pg/mL, CRP≥2.4mg/L, and MMP-9≤397ng/mL, respectively, assessed in a multivariate logistic regression model (ROCAUC of 0.72). Wild type(WT) and RAGE-deficient(Ager-/-) mice were exposed to PM or PBS-control by oropharyngeal aspiration. Lung function, airway hyperreactivity, bronchoalveolar lavage, histology, transcription factors and plasma/BAL cytokines were quantified. WT-PM mice had decreased FEV and compliance, and increased airway resistance and methacholine reactivity after 24-hours. Decreased IFN-γ and increased LPA were observed in WT-PM mice; similar findings have been reported for firefighters who eventually develop WTC-LI. In the murine model, lack of RAGE was protective from loss of lung function and airway hyperreactivity and was associated with modulation of MAP kinases. We conclude that in a multivariate adjusted model increased sRAGE is

  1. Receptor for advanced glycation end-products and World Trade Center particulate induced lung function loss: A case-cohort study and murine model of acute particulate exposure.

    Directory of Open Access Journals (Sweden)

    Erin J Caraher

    Full Text Available World Trade Center-particulate matter(WTC-PM exposure and metabolic-risk are associated with WTC-Lung Injury(WTC-LI. The receptor for advanced glycation end-products (RAGE is most highly expressed in the lung, mediates metabolic risk, and single-nucleotide polymorphisms at the AGER-locus predict forced expiratory volume(FEV. Our objectives were to test the hypotheses that RAGE is a biomarker of WTC-LI in the FDNY-cohort and that loss of RAGE in a murine model would protect against acute PM-induced lung disease. We know from previous work that early intense exposure at the time of the WTC collapse was most predictive of WTC-LI therefore we utilized a murine model of intense acute PM-exposure to determine if loss of RAGE is protective and to identify signaling/cytokine intermediates. This study builds on a continuing effort to identify serum biomarkers that predict the development of WTC-LI. A case-cohort design was used to analyze a focused cohort of male never-smokers with normal pre-9/11 lung function. Odds of developing WTC-LI increased by 1.2, 1.8 and 1.0 in firefighters with soluble RAGE (sRAGE≥97pg/mL, CRP≥2.4mg/L, and MMP-9≤397ng/mL, respectively, assessed in a multivariate logistic regression model (ROCAUC of 0.72. Wild type(WT and RAGE-deficient(Ager-/- mice were exposed to PM or PBS-control by oropharyngeal aspiration. Lung function, airway hyperreactivity, bronchoalveolar lavage, histology, transcription factors and plasma/BAL cytokines were quantified. WT-PM mice had decreased FEV and compliance, and increased airway resistance and methacholine reactivity after 24-hours. Decreased IFN-γ and increased LPA were observed in WT-PM mice; similar findings have been reported for firefighters who eventually develop WTC-LI. In the murine model, lack of RAGE was protective from loss of lung function and airway hyperreactivity and was associated with modulation of MAP kinases. We conclude that in a multivariate adjusted model increased s

  2. Search for the lowest irradiation dose from literatures on radiation-induced breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizawa, Y; Kusama, T [Tokyo Univ. (Japan). Faculty of Medicine

    1975-12-01

    A survey of past case reports concerning radiation-induced breast cancer was carried out in order to find the lowest irradiation dose. The search of literature published since 1951 revealed 10 cases of radiation-induced breast cancer. Only 5 cases had precise descriptions of the irradiation dose. The lowest irradiation dose was estimated at 1470 rads in the case of external X-ray irradiation for tuberous angioma. All of cases of radiation-induced breast cancer had received radiation for the treatment of nonmalignant tumors, such as pulmonary tuberculosis, mastitis, and tuberous angioma. There also were three statistical studies. The first concerned atomic bomb survivors, the second, pulmoanry tuberculous patients subjected to frequent fluoroscopies, and the third, patients of acute post partum mastitis. These statistical studies had revealed a significant increase in the incidence of breast cancer in the irradiated group, but there was little information about the lowest irradiation dose. It was noticed that radiation-induced breast cancer was more numerous in the upper inner quadrant of the breast. Most histopathological findings of radiation-induced breast cancer involved duct cell carcinoma. The latent period was about 15 years.

  3. Bile acids in radiation-induced diarrhea

    International Nuclear Information System (INIS)

    Arlow, F.L.; Dekovich, A.A.; Priest, R.J.; Beher, W.T.

    1987-01-01

    Radiation-induced bowel disease manifested by debilitating diarrhea is an unfortunate consequence of therapeutic irradiation for pelvic malignancies. Although the mechanism for this diarrhea is not well understood, many believe it is the result of damage to small bowel mucosa and subsequent bile acid malabsorption. Excess amounts of bile acids, especially the dihydroxy components, are known to induce water and electrolyte secretion and increase bowel motility. We have directly measured individual and total bile acids in the stool samples of 11 patients with radiation-induced diarrhea and have found bile acids elevated two to six times normal in eight of them. Our patients with diarrhea and increased bile acids in their stools had prompt improvement when given cholestyramine. They had fewer stools and returned to a more normal life-style

  4. Radiation-induced conductivity of polynaphthoyl benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Tiutnev, A P; Berlin, A M; Saenko, V S; Rusanov, A L; Korshak, V V

    1985-01-01

    The nonstationary radiation-induced conductivity of polynaphthoyl benzimidazole, synthesized by single-stage high-temperature catalytic polycondensation, is investigated experimentally. It is shown that the radiation-induced conductivity of this material is characterized by an anomalous (non-Gaussian) transfer of excess charge carriers. The activation energy of the delayed component (0.1 ms after pulse termination) is determined to be 0.12 eV; the volt-ampere characteristic of this component is nonlinear, with the coefficient of nonlinearity increasing with the intensity of the external electric field. Experimental results are interpreted on the basis of the phenomenological theory of jump conductivity proposed by Zviagin. 15 references.

  5. Ionizing radiation induced malignancies in man

    International Nuclear Information System (INIS)

    Dutrillaux, B.

    1997-01-01

    Using data on gene and chromosome alterations in human cancers, it is proposed that most radiation induced cancers are a consequence of recessive mutations of tumor suppressor genes. This explains the long delay between radiation exposure and the cancer onset. As a consequence, radiation induced cancers belong to groups of tumors where no specific translocations (forming or activating oncogenes) but multiple unbalanced chromosome rearrangements (deletions unmasking recessive mutations) exist. This explains why osteosarcomas, malignant fibrous histiocytoma, chondrosarcomas are frequently induced, but not liposarcoma, Ewing sarcomas and rhabdomyosarcomas, among others. A single exception confirms this rule: papillary thyroid cancer, frequently induced in exposed children, in which structural rearrangements frequently form a RET/PTC3 fusion gene. This fusion gene is the results of the inversion of a short segment of chromosome 10, and it is assumed that such rearrangement (small para-centric inversion) can easily occur after exposure to radiations, at contrast with translocations between to genes belonging to different chromosomes. (author)

  6. Radiation-induced degradation of pollutants

    International Nuclear Information System (INIS)

    Proksch, E.

    1988-01-01

    This article outlines the fundamentals of radiation-induced degradation of noxious substances in drinking water and waste water and discusses the relevant literature. Radiation methods present a number of advantages and disadvantages, which should carefully be considered in each case. In many cases, there seems to be merit in combining the radiation method with other techniques, as e.g. ozone treatement and biodegradation. 30 refs., 3 figs. (Author)

  7. Radiation induced glioblastoma. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Naoki; Kayama, Takamasa; Sakurada, Kaori; Saino, Makoto; Kuroki, Akira [Yamagata Univ. (Japan). School of Medicine

    2000-05-01

    We report a surgical case of a 54-year-old woman with a radiation induced glioblastoma. At the age of 34, the patient was diagnosed to have a non-functioning pituitary adenoma. It was partially removed followed by 50 Gy focal irradiation with a 5 x 5 cm lateral opposed field. Twenty years later, she suffered from rapidly increasing symptoms such as aphasia and right hemiparesis. MRI showed a large mass lesion in the left temporal lobe as well as small mass lesions in the brain stem and the right medial temporal lobe. These lesions situated within the irradiated field. Magnetic resonance spectroscopy revealed relatively high lactate signal and decreased N-acetyl aspartate, choline, creatine and phosphocreatine signals. Increased lactate signal meant anaerobic metabolism that suggested the existence of a rapidly growing malignant tumor. Thus, we planned surgical removal of the left temporal lesion with the diagnosis of a radiation induced malignant glioma. The histological examination revealed a glioblastoma with radiation necrosis. MIB-1 staining index was 65%. Postoperatively, her symptoms improved, but she died from pneumonia 1 month after the surgery. A autopsy was obtained. The lesion of the left temporal lobe was found to have continuity to the lesion in the midbrain, the pons and the right temporal lobe as well. High MIB-1 staining index suggested that a radiation induced glioblastoma had high proliferative potential comparing with a de novo and secondary glioblastoma. (author)

  8. Radiation-induced cancers in man

    International Nuclear Information System (INIS)

    Hirose, Fumio

    1978-01-01

    Radiation-induced cancers in man were divided into three groups, a group in which cancers occurred after atomic bomb exposure, a group in which cancers occurred in radiologists and other medical specialists, and a group in which cancers occurred after exposure to diagnostic radiation, and they were summarized. In atomic bomb survivors leukemia, thyroid cancer, salivary gland cancer, lung cancer, and breast cancer occurred so frequently. In addition to them, mortality ratios by malignant lymphoma, stomach cancer, esophageal cancer, and by cancer of urinary tract were increased. The incidence of leukemia was decreased in those who treated radiation owing to the development of the protection of occupational exposure, and the incidence of radiation-induced cancers was decreased in patients owing to the improvement of therapy. However, a new problem has arisen as to the occurrence of cancers after medical exposure, such as various histological types of cancers after the treatment of skin diseases on the head, and breast cancer after the treatment of pneumothorax. Dose-to-effect relation, hereditary factors, effect of age, immunological influences and endocrine actions were also studied in each radiation-induced cancer. (Ichikawa, K.)

  9. Radiation-induced heart injury. Radiopathological study

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Y; Niibe, H [Gunma Univ., Maebashi (Japan). School of Medicine

    1975-11-01

    In order to identify radiation-induced heart injury and to differentiate it from heart disease, an attempt was made to clarify post-irradiation heart injury by investigating the histological changes which occur during the interval between the irradiation and the time of demonstrable histological changes. A study was made of 83 autopsies in which most of the primary neoplasms were breast cancers, lung cancers and mediastinal tumors. In 43 of these autopsies the heart had been irradiated. Sixty eight dd-strain mice were also used for microautoradiographic study. Histological changes in the heart were observed in 27 of the 43 cases receiving irradiation. The limit of the tolerance dose to the heart for indicating histological changes was 1220 ret in humans. The latent period without histological changes was 2.7 months after initiation of radiation therapy. Greater heart injury was observed after re-irradiation or after the combined therapy of radiation and chemotherapy especially mitomycin (MMC). The histological findings after treatment with MMC were similar to those of radiation-induced heart injury. Results of the study indicate that the damage is secondary to radiation-induced changes of the vascula connective tissue.

  10. Genetic alterations during radiation-induced carcinogenesis

    International Nuclear Information System (INIS)

    Kodama, Seiji

    1995-01-01

    This paper reviews radiation-induced genetic alterations and its carcinogenesis, focusing on the previous in vitro assay outcome. A colony formation assay using Syrian hamster fetal cells and focus formation assay using mouse C3H10T1/2 cells are currently available to find malignant transformation of cells. Such in vitro assays has proposed the hypothesis that radiation-induced carcinogenesis arises from at least two-stage processes; i.e., that an early step induced by irradiation plays an important role in promoting the potential to cause the subsequent mutation. A type of genetic instability induced by radiation results in a persistently elevated frequency of spontaneous mutations, so-called the phenomenon of delayed reproductive death. One possible mechanism by which genetic instability arises has been shown to be due to the development of abnormality in the gene group involved in the maintenance mechanism of genome stability. Another possibility has also been shown to stem from the loss of telomere (the extremities of a chromosome). The importance of search for radiation-induced genetic instability is emphasized in view of the elucidation of carcinogenesis. (N.K.)

  11. Radiation-induced cancers in man

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, F [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

    1978-07-01

    Radiation-induced cancers in man were divided into three groups, a group in which cancers occurred after atomic bomb exposure, a group in which cancers occurred in radiologists and other medical specialists, and a group in which cancers occurred after exposure to diagnostic radiation, and they were summarized. In atomic bomb survivors leukemia, thyroid cancer, salivary gland cancer, lung cancer, and breast cancer occurred so frequently. In addition to them, mortality ratios by malignant lymphoma, stomach cancer, esophageal cancer, and by cancer of urinary tract were increased. The incidence of leukemia was decreased in those who treated radiation owing to the development of the protection of occupational exposure, and the incidence of radiation-induced cancers was decreased in patients owing to the improvement of therapy. However, a new problem has arisen as to the occurrence of cancers after medical exposure, such as various histological types of cancers after the treatment of skin diseases on the head, and breast cancer after the treatment of pneumothorax. Dose-to-effect relation, hereditary factors, effect of age, immunological influences and endocrine actions were also studied in each radiation-induced cancer.

  12. Probabilistic methodology for estimating radiation-induced cancer risk

    International Nuclear Information System (INIS)

    Dunning, D.E. Jr.; Leggett, R.W.; Williams, L.R.

    1981-01-01

    The RICRAC computer code was developed at Oak Ridge National Laboratory to provide a versatile and convenient methodology for radiation risk assessment. The code allows as input essentially any dose pattern commonly encountered in risk assessments for either acute or chronic exposures, and it includes consideration of the age structure of the exposed population. Results produced by the analysis include the probability of one or more radiation-induced cancer deaths in a specified population, expected numbers of deaths, and expected years of life lost as a result of premature fatalities. These calculatons include consideration of competing risks of death from all other causes. The program also generates a probability frequency distribution of the expected number of cancers in any specified cohort resulting from a given radiation dose. The methods may be applied to any specified population and dose scenario

  13. DNA Double-Strand Break Analysis by {gamma}-H2AX Foci: A Useful Method for Determining the Overreactors to Radiation-Induced Acute Reactions Among Head-and-Neck Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Goutham, Hassan Venkatesh; Mumbrekar, Kamalesh Dattaram [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India); Vadhiraja, Bejadi Manjunath [Manipal Hospital, Bangalore, Karnataka (India); Fernandes, Donald Jerard; Sharan, Krishna [Department of Radiotherapy and Oncology, Shiridi Sai Baba Cancer Hospital and Research Centre, Kasturba Hospital, Manipal, Karnataka (India); Kanive Parashiva, Guruprasad; Kapaettu, Satyamoorthy [Division of Biotechnology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India); Bola Sadashiva, Satish Rao, E-mail: satishraomlsc@gmail.com [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India)

    2012-12-01

    Purpose: Interindividual variability in normal tissue toxicity during radiation therapy is a limiting factor for successful treatment. Predicting the risk of developing acute reactions before initiation of radiation therapy may have the benefit of opting for altered radiation therapy regimens to achieve minimal adverse effects with improved tumor cure. Methods and Materials: DNA double-strand break (DSB) induction and its repair kinetics in lymphocytes of head-and-neck cancer patients undergoing chemoradiation therapy was analyzed by counting {gamma}-H2AX foci, neutral comet assay, and a modified version of neutral filter elution assay. Acute normal tissue reactions were assessed by Radiation Therapy Oncology Group criteria. Results: The correlation between residual DSBs and the severity of acute reactions demonstrated that residual {gamma}-H2AX foci in head-and-neck cancer patients increased with the severity of oral mucositis and skin reaction. Conclusions: Our results suggest that {gamma}-H2AX analysis may have predictive implications for identifying the overreactors to mucositis and skin reactions among head-and-neck cancer patients prior to initiation of radiation therapy.

  14. Radiation-induced apoptosis in F9 teratocarcinoma cells

    International Nuclear Information System (INIS)

    Langley, R.E.; Palayoor, S.T.; Coleman, C.N.; Bump, E.A.

    1994-01-01

    We have found that F9 murine teratocarcinoma cells undergo morphological changes and internucleosomal DNA fragmentation characteristic of apoptosis after exposure to ionizing radiation. We studied the time course, radiation dose-response, and the effects of protein and RNA synthesis inhibitors on this process. The response is dose dependent in the range 2-12 Gy. Internucleosomal DNA fragmentation can be detected as early as 6 h postirradiation and is maximal by 48 h. Cycloheximide, a protein synthesis inhibitor, and 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole, an RNA synthesis inhibitor, both induced internucleosomal DNA fragmentation in the unirradiated cells and enhanced radiation-induced DNA fragmentation. F9 cells can be induced to differentiate into cells resembling endoderm with retinoic acid. After irradiation, differentiated F9 cells exhibit less DNA fragmentation than stem cells. This indicates that ionizing radiation can induce apoptosis in non-lymphoid tumours. We suggest that embryonic tumour cells may be particularly susceptible to agents that induce apoptosis. (Author)

  15. Radiation-induced apoptosis in F9 teratocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Langley, R E; Palayoor, S T; Coleman, C N; Bump, E A [Joint Center for Radiation Therapy and Dana Farber Cancer Inst., Boston (United States)

    1994-05-01

    We have found that F9 murine teratocarcinoma cells undergo morphological changes and internucleosomal DNA fragmentation characteristic of apoptosis after exposure to ionizing radiation. We studied the time course, radiation dose-response, and the effects of protein and RNA synthesis inhibitors on this process. The response is dose dependent in the range 2-12 Gy. Internucleosomal DNA fragmentation can be detected as early as 6 h postirradiation and is maximal by 48 h. Cycloheximide, a protein synthesis inhibitor, and 5,6-dichloro-1-[beta]-D-ribofuranosylbenzimidazole, an RNA synthesis inhibitor, both induced internucleosomal DNA fragmentation in the unirradiated cells and enhanced radiation-induced DNA fragmentation. F9 cells can be induced to differentiate into cells resembling endoderm with retinoic acid. After irradiation, differentiated F9 cells exhibit less DNA fragmentation than stem cells. This indicates that ionizing radiation can induce apoptosis in non-lymphoid tumours. We suggest that embryonic tumour cells may be particularly susceptible to agents that induce apoptosis. (Author).

  16. The nature and principles of the radiation-induced cancerogenesis

    International Nuclear Information System (INIS)

    Lips'ka, A.YI.; Serkyiz, Ya.Yi.

    2004-01-01

    The paper represents the analysis of the authors and literary data concerning the nature and principles of the radiation-induced neoplasms. The mechanisms of the radiation-induced cancerogenesis development are not clear understood. The experimental data altogether do not allow developing the mathematical model of the radiation-induced cancerogenesis at the molecular level. This model has to take into account all necessary indices including radiation factor and the state of the organism. The general principles of the radiation-induced cancerogenesis have been formulated in the present review. It is possible to use these principles in order to predict and calculate the risks of the radiation-induced neoplasms

  17. Radiation-induced gene expression in human subcutaneous fibroblasts is predictive of radiation-induced fibrosis

    DEFF Research Database (Denmark)

    Rødningen, Olaug Kristin; Børresen-Dale, Anne-Lise; Alsner, Jan

    2008-01-01

    BACKGROUND AND PURPOSE: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last...... years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. MATERIALS AND METHODS: Fibroblast cell lines from 31 individuals......-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. RESULTS: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF...

  18. Vitamin D Deficiency Is Associated With the Severity of Radiation-Induced Proctitis in Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Ghorbanzadeh-Moghaddam, Amir [Medical Student' s Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Gholamrezaei, Ali, E-mail: Gholamrezaei@med.mui.ac.ir [Medical Student' s Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Poursina Hakim Research Institution, Isfahan (Iran, Islamic Republic of); Hemati, Simin [Department of Radiotherapy Oncology, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of)

    2015-07-01

    Purpose: Radiation-induced injury to normal tissues is a common complication of radiation therapy in cancer patients. Considering the role of vitamin D in mucosal barrier hemostasis and inflammatory responses, we investigated whether vitamin D deficiency is associated with the severity of radiation-induced acute proctitis in cancer patients. Methods and Materials: This prospective observational study was conducted in cancer patients referred for pelvic radiation therapy. Serum concentration of 25-hydroxyvitamin D was measured before radiation therapy. Vitamin D deficiency was defined as 25-hydroxyvitamin D concentrations of <35 nmol/L and <40 nmol/L in male and female patients, respectively, based on available normative data. Acute proctitis was assessed after 5 weeks of radiation therapy (total received radiation dose of 50 Gy) and graded from 0 to 4 using Radiation Therapy Oncology Group (RTOG) criteria. Results: Ninety-eight patients (57.1% male) with a mean age of 62.8 ± 9.1 years were studied. Vitamin D deficiency was found in 57 patients (58.1%). Symptoms of acute proctitis occurred in 72 patients (73.4%) after radiation therapy. RTOG grade was significantly higher in patients with vitamin D deficiency than in normal cases (median [interquartile range] of 2 [0.5-3] vs 1 [0-2], P=.037). Vitamin D deficiency was associated with RTOG grade of ≥2, independent of possible confounding factors; odds ratio (95% confidence interval) = 3.07 (1.27-7.50), P=.013. Conclusions: Vitamin D deficiency is associated with increased severity of radiation-induced acute proctitis. Investigating the underlying mechanisms of this association and evaluating the effectiveness of vitamin D therapy in preventing radiation-induced acute proctitis is warranted.

  19. Vitamin D Deficiency Is Associated With the Severity of Radiation-Induced Proctitis in Cancer Patients

    International Nuclear Information System (INIS)

    Ghorbanzadeh-Moghaddam, Amir; Gholamrezaei, Ali; Hemati, Simin

    2015-01-01

    Purpose: Radiation-induced injury to normal tissues is a common complication of radiation therapy in cancer patients. Considering the role of vitamin D in mucosal barrier hemostasis and inflammatory responses, we investigated whether vitamin D deficiency is associated with the severity of radiation-induced acute proctitis in cancer patients. Methods and Materials: This prospective observational study was conducted in cancer patients referred for pelvic radiation therapy. Serum concentration of 25-hydroxyvitamin D was measured before radiation therapy. Vitamin D deficiency was defined as 25-hydroxyvitamin D concentrations of <35 nmol/L and <40 nmol/L in male and female patients, respectively, based on available normative data. Acute proctitis was assessed after 5 weeks of radiation therapy (total received radiation dose of 50 Gy) and graded from 0 to 4 using Radiation Therapy Oncology Group (RTOG) criteria. Results: Ninety-eight patients (57.1% male) with a mean age of 62.8 ± 9.1 years were studied. Vitamin D deficiency was found in 57 patients (58.1%). Symptoms of acute proctitis occurred in 72 patients (73.4%) after radiation therapy. RTOG grade was significantly higher in patients with vitamin D deficiency than in normal cases (median [interquartile range] of 2 [0.5-3] vs 1 [0-2], P=.037). Vitamin D deficiency was associated with RTOG grade of ≥2, independent of possible confounding factors; odds ratio (95% confidence interval) = 3.07 (1.27-7.50), P=.013. Conclusions: Vitamin D deficiency is associated with increased severity of radiation-induced acute proctitis. Investigating the underlying mechanisms of this association and evaluating the effectiveness of vitamin D therapy in preventing radiation-induced acute proctitis is warranted

  20. Understanding the role of p53 in adaptive response to radiation-induced germline mutations

    International Nuclear Information System (INIS)

    Langlois, N.L.; Quinn, J.S.; Somers, C.M.; Boreham, D.R.; Mitchel, R.E.J.

    2003-01-01

    Full text: Radiation-induced adaptive response is now a widely studied area of radiation biology. Studies have demonstrated reduced levels of radiation-induced biological damage when an 'adaptive dose' is given before a higher 'challenge dose' compared to when the challenge dose is given alone. It has been shown in some systems to be a result of inducible cellular repair systems. The adaptive response has been clearly demonstrated in many model systems, however its impact on heritable effects in the mammalian germline has never been studied. Expanded Simple Tandem Repeat (ESTR) loci have been used as markers demonstrating that induced heritable mutations in mice follow a dose-response relationship. Recent data in our laboratory show preliminary evidence of radiation-induced adaptive response suppressing germline mutations at ESTR loci in wild type mice. The frequency of heritable mutations was significantly reduced when a priming dose of 0.1 Gy was given 24 hours prior to a 1 Gy acute challenging dose. We are now conducting a follow-up study to attempt to understand the mechanism of this adaptive response. P53 is known to play a significant role in governing apoptosis, DNA repair and cancer induction. In order to determine what function p53 has in the adaptive response for heritable mutations, we have mated radiation treated Trp53+/- male mice (C57Bl) to untreated, normal females (C57Bl). Using DNA fingerprinting, we are investigating the rate of inherited radiation-induced mutations on pre- and post-meiotic radiation-treated gametocytes by examining mutation frequencies in offspring DNA. If p53 is integral in the mechanism of adaptive response, we should not see an adaptive response in radiation-induced heritable mutations in these mice. This research is significant in that it will provide insight to understanding the mechanism behind radiation-induced adaptive response in the mammalian germline

  1. Radiation-induced cerebrovascular disease in children

    International Nuclear Information System (INIS)

    Wright, T.L.; Bresnan, M.J.

    1976-01-01

    Radiation-induced internal carotid artery occlusion has not been well recognized previously as a cause of childhood cerebrovascular disease. A child who had received radiation as a neonate for a hemangioma involving the left orbit at the age of 6 years experienced a recurrent right-sided paresis, vascular headaches, and speech difficulties. Angiography showed a hypoplastic left carotid artery with occlusion of both the anterior and middle cerebral arteries. Collateral vessels bypassed the occluded-stenotic segments. Review of the literature showed two additional cases of large vessel occlusion in childhood associated with anastomatic telangiectatic vessel development following early radiation therapy of facial hemangioma

  2. Radiation induced peroxidation in model lipid systems

    International Nuclear Information System (INIS)

    Dahlan, K.Z.B.H.M.

    1981-08-01

    In the studies of radiation induced lipid peroxidation, lecithin-liposomes and aqueous micellar solutions of sodium linoleate (or linoleic acid) have been used as models of lipid membrane systems. The liposomes and aqueous linoleate micelles were irradiated in the presence of O 2 and N 2 O/O 2 (80/20 v/v). The peroxidation was initiated using gamma radiation from 60 Co radiation source and was monitored by measuring the increase in absorbance of conjugated diene at 232 nm and by the thiobarbituric acid (TBA) test. The oxidation products were also identified by GLC and GLC-MS analysis. (author)

  3. Radiation-induced damage of membranes

    International Nuclear Information System (INIS)

    Yonei, Shuji

    1977-01-01

    An outline of membranous structure was stated, and radiation-induced damage of membranes were surveyed. By irradiation, permeability of membranes, especially passive transportation mechanism, was damaged, and glycoprotein in the surface layers of cells and the surface layer structures were changed. The intramembranous damage was induced by decrease of electrophoresis of nuclear mambranes and a quantitative change of cytochrome P450 of microsomal membranes of the liver, and peroxidation of membranous lipid and SH substitute damage of membranous protein were mentioned as the mechanism of membranous damage. Recovery of membranous damage depends on radiation dose and temperature, and membranous damage participates largely in proliferation death. (tsunoda, M.)

  4. Radiation-induced sensitisation of stainless steels

    International Nuclear Information System (INIS)

    Norris, D.I.R.

    1987-01-01

    The book contains the proceedings of a symposium on radiation-induced sensitization of stainless steels, which took place at Berkeley, United Kingdom, 1986. The purpose of the symposium was to examine the mechanism leading to inter-granular corrosion of 20%Cr/25% Ni/Nb stainless steel cladding of AGR fuel following irradiation. Nine papers are presented, of which three are theoretical, two papers are based upon corrosion studies of 20%Cr/25%Ni/Nb steel, and the remaining are concerned with compositional redistribution and its measurement. (U.K.)

  5. Injection profiles with radiation induced copolymers

    International Nuclear Information System (INIS)

    Knight, B.L.; Rhudy, J.S.; Gogarty, W.B.

    1976-01-01

    The injectivity profile of a heterogeneous formation and/or vertical conformance is improved by injecting an aqueous solution into the formation, the solution containing a polymer obtained as a product of radiation-induced polymerization of acrylamide and/or methacrylamide and acrylic acid, methacrylic acid, and/or alkali metal salts thereof. The polymerization is preferably carried out in a 10 to 60 percent aqueous solution with gamma radiation; the aqueous monomer solution preferably contains 25 to 99 percent acrylamide and 1 to 75 percent sodium acrylate. Immiscible, miscible, or miscible-like displacing processes can be used in conjunction with this invention. 20 claims

  6. TH-E-BRF-09: Gaussian Mixture Model Analysis of Radiation-Induced Parotid-Gland Injury: An Ultrasound Study of Acute and Late Xerostomia in Head-And-Neck Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, T [Department of Radiation Oncology and Winship Cancer Institute, Emory Univ, Atlanta, GA (United States); Yu, D; Beitler, J; Curran, W; Yang, X [Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA (United States); Tridandapani, S [Department of Radiology and Imaging Sciences and Winship Cancer Institute, Emory University, Atlanta, GA (United States); Bruner, D [School of Nursing and Winship Cancer Institute, Emory Univesity, Atlanta, GA (United States)

    2014-06-15

    Purpose: Xerostomia (dry mouth), secondary to parotid-gland injury, is a distressing side-effect in head-and-neck radiotherapy (RT). This study's purpose is to develop a novel ultrasound technique to quantitatively evaluate post-RT parotid-gland injury. Methods: Recent ultrasound studies have shown that healthy parotid glands exhibit homogeneous echotexture, whereas post-RT parotid glands are often heterogeneous, with multiple hypoechoic (inflammation) or hyperechoic (fibrosis) regions. We propose to use a Gaussian mixture model to analyze the ultrasonic echo-histogram of the parotid glands. An IRB-approved clinical study was conducted: (1) control-group: 13 healthy-volunteers, served as the control; (2) acutetoxicity group − 20 patients (mean age: 62.5 ± 8.9 years, follow-up: 2.0±0.8 months); and (3) late-toxicity group − 18 patients (mean age: 60.7 ± 7.3 years, follow-up: 20.1±10.4 months). All patients experienced RTOG grade 1 or 2 salivary-gland toxicity. Each participant underwent an ultrasound scan (10 MHz) of the bilateral parotid glands. An echo-intensity histogram was derived for each parotid and a Gaussian mixture model was used to fit the histogram using expectation maximization (EM) algorithm. The quality of the fitting was evaluated with the R-squared value. Results: (1) Controlgroup: all parotid glands fitted well with one Gaussian component, with a mean intensity of 79.8±4.9 (R-squared>0.96). (2) Acute-toxicity group: 37 of the 40 post-RT parotid glands fitted well with two Gaussian components, with a mean intensity of 42.9±7.4, 73.3±12.2 (R-squared>0.95). (3) Latetoxicity group: 32 of the 36 post-RT parotid fitted well with 3 Gaussian components, with mean intensities of 49.7±7.6, 77.2±8.7, and 118.6±11.8 (R-squared>0.98). Conclusion: RT-associated parotid-gland injury is common in head-and-neck RT, but challenging to assess. This work has demonstrated that the Gaussian mixture model of the echo-histogram could quantify acute and

  7. TH-E-BRF-09: Gaussian Mixture Model Analysis of Radiation-Induced Parotid-Gland Injury: An Ultrasound Study of Acute and Late Xerostomia in Head-And-Neck Radiotherapy

    International Nuclear Information System (INIS)

    Liu, T; Yu, D; Beitler, J; Curran, W; Yang, X; Tridandapani, S; Bruner, D

    2014-01-01

    Purpose: Xerostomia (dry mouth), secondary to parotid-gland injury, is a distressing side-effect in head-and-neck radiotherapy (RT). This study's purpose is to develop a novel ultrasound technique to quantitatively evaluate post-RT parotid-gland injury. Methods: Recent ultrasound studies have shown that healthy parotid glands exhibit homogeneous echotexture, whereas post-RT parotid glands are often heterogeneous, with multiple hypoechoic (inflammation) or hyperechoic (fibrosis) regions. We propose to use a Gaussian mixture model to analyze the ultrasonic echo-histogram of the parotid glands. An IRB-approved clinical study was conducted: (1) control-group: 13 healthy-volunteers, served as the control; (2) acutetoxicity group − 20 patients (mean age: 62.5 ± 8.9 years, follow-up: 2.0±0.8 months); and (3) late-toxicity group − 18 patients (mean age: 60.7 ± 7.3 years, follow-up: 20.1±10.4 months). All patients experienced RTOG grade 1 or 2 salivary-gland toxicity. Each participant underwent an ultrasound scan (10 MHz) of the bilateral parotid glands. An echo-intensity histogram was derived for each parotid and a Gaussian mixture model was used to fit the histogram using expectation maximization (EM) algorithm. The quality of the fitting was evaluated with the R-squared value. Results: (1) Controlgroup: all parotid glands fitted well with one Gaussian component, with a mean intensity of 79.8±4.9 (R-squared>0.96). (2) Acute-toxicity group: 37 of the 40 post-RT parotid glands fitted well with two Gaussian components, with a mean intensity of 42.9±7.4, 73.3±12.2 (R-squared>0.95). (3) Latetoxicity group: 32 of the 36 post-RT parotid fitted well with 3 Gaussian components, with mean intensities of 49.7±7.6, 77.2±8.7, and 118.6±11.8 (R-squared>0.98). Conclusion: RT-associated parotid-gland injury is common in head-and-neck RT, but challenging to assess. This work has demonstrated that the Gaussian mixture model of the echo-histogram could quantify acute and

  8. Phase II study assessing the effectiveness of Biafine cream as a prophylactic agent for radiation-induced acute skin toxicity to the breast in women undergoing radiotherapy with concomitant CMF chemotherapy

    International Nuclear Information System (INIS)

    Szumacher, Ewa; Wighton, Anne; Franssen, Edmee; Chow, Edward; Tsao, May; Ackerman, Ida; Andersson, Lourdes; Kim, John; Wojcicka, Anna; Ung, Yee; Sixel, Katharina; Hayter, Charles

    2001-01-01

    Purpose: To assess the efficacy of Biafine cream in preventing Grade 2 acute radiation dermatitis, according to the National Cancer Institute of Canada skin radiation toxicity criteria in patients undergoing concomitant adjuvant chemotherapy and radiotherapy to the breast. Methods and Materials: Sixty patients participated in this study. Patients were treated with a lumpectomy followed by concomitant chemotherapy and radiotherapy to the breast. Biafine cream was applied daily, starting on the first day and ending 2 weeks post-radiotherapy. Patients underwent weekly skin assessments throughout radiotherapy and at 2 and 4 weeks after treatment. Outcome measures were assessed using a Skin Assessment Questionnaire that was scored according to the National Cancer Institute of Canada skin radiation toxicity criteria and a self-administered questionnaire that evaluated skin symptoms. Results: The maximum skin toxicity observed during the course of treatment was as follows: less than Grade 2 toxicity, 15% (9 patients); Grade 2, 83% (50 patients); Grade 3, 2% (1 patient); Grade 4, 0% (0 patients). The majority of the radiation dermatitis was observed after 3 weeks of radiotherapy. Conclusion: The majority of patients who underwent concomitant chemo- and radiotherapy for breast cancer developed Grade 2 radiation dermatitis with the use of Biafine cream. However, no treatment delays or interruptions were observed because of skin toxicity

  9. Radiation-induced thyroid cancer after radiotherapy for childhood cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jiravova, M. [Department of Nuclear Medicine and Endocrinology, Faculty Hospital Motol, Uk, Prague (Czech Republic)

    2012-07-01

    Full text of the publication follows: The thyroid gland in children is among the most sensitive organs to the carcinogenic effects of ionizing radiation, and very young children are at especially high risk. Due to extreme sensitivity of the thyroid gland in children, there is a risk of radiation - induced thyroid cancer even when the thyroid gland is outside the irradiated field. Increased incidence of thyroid cancer has been noted following radiotherapy not only for childhood Hodgkin disease (majority of observed patients), but also for non-Hodgkin lymphoma, neuroblastoma, Wilms tumor, acute lymphocytic leukemia and tumors of the central nervous system also. Radiation-induced tumors begin to appear 5-10 years after irradiation and excess risk persists for decades, perhaps for the remainder of life. The incidence of thyroid cancer is two- to threefold higher among females than males. Most of the thyroid cancers that occur in association with irradiation are of the papillary type, for which the cure rate is high if tumors are detected early. Our Department in co-operation with Department of Children Hematology and Oncology Charles University Second Faculty of Medicine and Faculty Hospital Motol monitors patients after therapy for cancer in childhood for the long term period. The monitoring is focused on detection of thyroid disorders that occur as last consequences of oncology therapy, especially early detection of nodular changes in thyroid gland and thyroid carcinogenesis. The survey presents two patients observed in our department that were diagnosed with the papillary thyroid carcinoma which occurred 15 and more years after radiotherapy for childhood cancer. After total thyroidectomy they underwent therapy with radioiodine. After radiotherapy it is necessary to pursue a long-term following and assure interdisciplinary co-operation which enables early detection of last consequences of radiotherapy, especially the most serious ones as secondary carcinogenesis

  10. Simulating Space Radiation-Induced Breast Tumor Incidence Using Automata.

    Science.gov (United States)

    Heuskin, A C; Osseiran, A I; Tang, J; Costes, S V

    2016-07-01

    Estimating cancer risk from space radiation has been an ongoing challenge for decades primarily because most of the reported epidemiological data on radiation-induced risks are derived from studies of atomic bomb survivors who were exposed to an acute dose of gamma rays instead of chronic high-LET cosmic radiation. In this study, we introduce a formalism using cellular automata to model the long-term effects of ionizing radiation in human breast for different radiation qualities. We first validated and tuned parameters for an automata-based two-stage clonal expansion model simulating the age dependence of spontaneous breast cancer incidence in an unexposed U.S. We then tested the impact of radiation perturbation in the model by modifying parameters to reflect both targeted and nontargeted radiation effects. Targeted effects (TE) reflect the immediate impact of radiation on a cell's DNA with classic end points being gene mutations and cell death. They are well known and are directly derived from experimental data. In contrast, nontargeted effects (NTE) are persistent and affect both damaged and undamaged cells, are nonlinear with dose and are not well characterized in the literature. In this study, we introduced TE in our model and compared predictions against epidemiologic data of the atomic bomb survivor cohort. TE alone are not sufficient for inducing enough cancer. NTE independent of dose and lasting ∼100 days postirradiation need to be added to accurately predict dose dependence of breast cancer induced by gamma rays. Finally, by integrating experimental relative biological effectiveness (RBE) for TE and keeping NTE (i.e., radiation-induced genomic instability) constant with dose and LET, the model predicts that RBE for breast cancer induced by cosmic radiation would be maximum at 220 keV/μm. This approach lays the groundwork for further investigation into the impact of chronic low-dose exposure, inter-individual variation and more complex space radiation

  11. Study on radiation-inducible genes

    International Nuclear Information System (INIS)

    Lim, Sang Yong; Kim, Dong Ho; Joe, Min Ho; Song, Hyu Npa

    2012-01-01

    Transcription of previously identified radiation-inducible genes, uscA and cyoA, was examined responding to radiation. The putative promoter regions of both genes were cloned into pRS415 vector containing lacZ, and the core promoter region necessary for radiation response were determined through promoter deletion method. To investigate the role of uscA, which is assumed to be small RNA related with radiation response, a deletion mutant strain of uscA was constructed. However, uscA deletion did not affect bacterial survival against radiation exposure. The use of bacteria as anticancer agents has attracted interest. In this study, we tried to develop tumor targeting bacteria in which the radiation-inducible promoter activate a transgene encoding a cytotoxic protein. For outward secretion of anticancer protein produced inside bacteria, the N-terminal 140 amino acid of SspH1 was found to function as a secretion signal peptide. To create an attenuated tumor-targeting bacteria, Salmonella ptsI mutant strain was constructed, and we found that its virulence decreased. Finally, the tumor-targeting ability of ptsI mutant was verified by the use of in-vivo imaging analysis

  12. Study on radiation-inducible genes

    International Nuclear Information System (INIS)

    Lim, Sang Yong; Kim, Dong Ho; Joe, Min Ho; Park, Hae Jun; Song, Hyu Npa

    2012-01-01

    Radiation-inducible genes of E. coli, which is a model strain for bacterial study, and Salmonella, which is a typical strain for pathogenic bacteria were compared through omic analysis. Heat shock response genes and prophage genes were induced by radiation in Salmonella, not in E. coli. Among prophage genes tested, STM2628 showed the highest activation by radiation, and approximately 1 kb promoter region was turned out to be necessary for radiation response. To screen an artificial promoter showing activation by 2 Gy, the high-throughput screening method using fluorescent MUG substrate was established. The use of bacteria as anticancer agents has attracted interest. In this study, we tried to develop tumor targeting bacteria in which the radiation-inducible promoter activate a transgene encoding a cytotoxic protein. To do this, a tumor-targeting hfq Salmonella mutant strain was constructed, and we found that its virulence decreased. For outward secretion of anticancer protein produced inside bacteria, the signal peptide of SspH1 was determined and the signal peptide was proven to be able to secrete an anticancer protein. Tumor xenograft mouse model was secured, which can be used for efficiency evaluation of bacterial tumor therapy

  13. Study of radiation-induced chromosomal aberrations

    International Nuclear Information System (INIS)

    Wolfring, E.

    2004-06-01

    A method for determining chromosomal aberrations was established for the purpose of examining the relative biological effectiveness (RBE) of photon radiation with respect to mammary epithelium cells. Cells were exposed to 25 kV X-radiation and to 200 kV X-radiation for comparison and the resulting concentrations of chromosomal aberrations were compared. The RBE M value for radiation-induced fragmentation was found to be 4.2 ± 2.4, while the RBE M value for radiation-induced generation of dicentric chromosomes was found to be 0.5 ± 0.5. In addition to the evaluation of chromosomal aberrations the number of cell cycles undergone by the cells was monitored by means of BrDU staining. As expected, the proportion of cells which underwent more than one cell cycle following exposure to 5 Gy was very low in both cases, amounting to 1.9% (25 kV) and 3.2 (200 kV). Non-radiated cells yielded control values of 26.0% and 12.6%, suggesting variations in external conditions from day to day

  14. Radiation- induced aneuploidy in mammalian germ cells

    International Nuclear Information System (INIS)

    Tease, C.

    1989-01-01

    The ability of ionizing radiation to induce aneuploidy in mammalian germ cells has been investigated experimentally in the laboratory mouse using a variety of cytogenetic and genetic methods. These studies have provided unambiguous evidence of induced nondisjunction in both male and female germ cells when the effect of irradiation is screened in meiotic cells or preimplantation embryos. In contrast, however, cytogenetic analyses of post-implantation embryos and genetic assays for induced chromosome gains have not found a significant radiation effect. These apparently contradictory findings may be reconciled if (a) radiation induces tertiary rather than primary trisomy, or (b) induces embryo-lethal genetic damage, such as deletions, in addition to numerical anomalies. Either or both of these explanations may account for the apparent loss during gestation of radiation-induced trisomic embryos. Extrapolating from the information so far available, it seems unlikely that environmental exposure to low doses if low dose rate radiation will result in a detectable increase in the rate of aneuploidy in the human population. (author)

  15. Study on radiation-inducible genes

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Yong; Kim, Dong Ho; Joe, Min Ho; Park, Hae Jun; Song, Hyu Npa

    2012-01-15

    Radiation-inducible genes of E. coli, which is a model strain for bacterial study, and Salmonella, which is a typical strain for pathogenic bacteria were compared through omic analysis. Heat shock response genes and prophage genes were induced by radiation in Salmonella, not in E. coli. Among prophage genes tested, STM2628 showed the highest activation by radiation, and approximately 1 kb promoter region was turned out to be necessary for radiation response. To screen an artificial promoter showing activation by 2 Gy, the high-throughput screening method using fluorescent MUG substrate was established. The use of bacteria as anticancer agents has attracted interest. In this study, we tried to develop tumor targeting bacteria in which the radiation-inducible promoter activate a transgene encoding a cytotoxic protein. To do this, a tumor-targeting hfq Salmonella mutant strain was constructed, and we found that its virulence decreased. For outward secretion of anticancer protein produced inside bacteria, the signal peptide of SspH1 was determined and the signal peptide was proven to be able to secrete an anticancer protein. Tumor xenograft mouse model was secured, which can be used for efficiency evaluation of bacterial tumor therapy.

  16. Study on radiation-inducible genes

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Yong; Kim, Dong Ho; Joe, Min Ho; Song, Hyu Npa

    2012-01-15

    Transcription of previously identified radiation-inducible genes, uscA and cyoA, was examined responding to radiation. The putative promoter regions of both genes were cloned into pRS415 vector containing lacZ, and the core promoter region necessary for radiation response were determined through promoter deletion method. To investigate the role of uscA, which is assumed to be small RNA related with radiation response, a deletion mutant strain of uscA was constructed. However, uscA deletion did not affect bacterial survival against radiation exposure. The use of bacteria as anticancer agents has attracted interest. In this study, we tried to develop tumor targeting bacteria in which the radiation-inducible promoter activate a transgene encoding a cytotoxic protein. For outward secretion of anticancer protein produced inside bacteria, the N-terminal 140 amino acid of SspH1 was found to function as a secretion signal peptide. To create an attenuated tumor-targeting bacteria, Salmonella ptsI mutant strain was constructed, and we found that its virulence decreased. Finally, the tumor-targeting ability of ptsI mutant was verified by the use of in-vivo imaging analysis.

  17. Cell kinetic studies on radiation induced leukemogenesis

    International Nuclear Information System (INIS)

    Nakao, Isamu; Suzuki, Gen; Imai, Yasufumi; Kawase, Yoshiko; Nose, Masako; Hirashima, Kunitake; Bessho, Masami

    1989-01-01

    The purpose of this study was threefold: (1) to determine the clonal origin of radiation-induced thymic lymphoma in mice with cellular mosaicism for phosphoglycerate kinase; (2) to determine the incidence and latent period of myeloid leukemia and thymic lymphoma induced by whole-body exposure to median doses (3.0 Gy or less) in RFM/MsNrs-2 mice; and (3) to examine the influence of human recombinant interleukin-2 (hrIL-2). Thymic lymphoma was of a single cell origin. The incidence of radiation-induced myeloid leukemia and thymic lymphoma in RFM mice increased in a dose dependent fashion. Mean latent periods of both myeloid leukemia and thymic lymphoma after irradiation became shorter in proportion to radiation doses. When hrIL-2 was injected to RFM mice receiving 3.0 Gy, mean survivals were shorter in thymoma-bearing mice than the control mice. This suggested that hrIL-2 shortens the promotion step of thymoma. Administration of hrIL-2 failed to alter the incidence of myeloid leukemia or the mean survival of mice having myeloid leukemia, indicating that the protocol of hrIL-2 administration was not so sufficient as to alter the myeloid leukemogenesis. (Namekawa, K)

  18. Radiation induced genetic damage in Aspergillus nidulans

    International Nuclear Information System (INIS)

    Georgiou, J.T.

    1984-01-01

    The mechanism by which ionizing radiation induces genetic damage in haploid and diploid conidia of Aspergillus nidulans was investigated. Although the linear dose-response curves obtained following low LET irradiation implied a 'single-hit' action of radiation, high LET radiations were much more efficient than low LET radiations, which suggests the involvement of a multiple target system. It was found that the RBE values for non-disjunction and mitotic crossing-over were very different. Unlike mitotic crossing-over, the RBE values for non-disjunction were much greater than for cell killing. This suggests that non-disjunction is a particularly sensitive genetical endpoint that is brought about by damage to a small, probably non-DNA target. Radiosensitisers were used to study whether radiation acts at the level of the DNA or some other cellular component. The sensitisation to electrons and/or X-rays by oxygen, and two nitroimidazoles (metronidazole and misonidazole) was examined for radiation induced non-disjunction, mitotic crossing-over, gene conversion, point mutation and cell killing. It was found that these compounds sensitised the cells considerably more to genetic damage than to cell killing. (author)

  19. Radiation-induced brain damage in children

    International Nuclear Information System (INIS)

    Oi, Shizuo; Kokunai, Takashi; Ijichi, Akihiro; Matsumoto, Satoshi; Raimondi, A.J.

    1990-01-01

    The nature and sequence of the radiation-induced changes in the brain were studied postmortem in 34 children with glioma, 22 of whom underwent central nervous system radiation therapy. Twenty received whole-brain or whole-neuroaxis radiation at a total mean dosage of 4063 cGy. Brain tissue alternations were analyzed histologically by means of various staining methods, including immunohistochemical techniques. The histological features of irradiated brains were compared with those of non-irradiated brains. Microscopic findings included demyelination (seven cases), focal necrosis (six cases), cortical atrophy (four cases), endothelial proliferation (four cases), and telangiectatic vascular proliferation with vascular thickening and oozing of a thick fluid (one case). Such findings were rare in non-irradiated patients. Demyelination was observed earliest in a patient who died 5 months after radiation therapy and was more common after 9 months. Focal necrosis was first observed 9 months post-irradiation but was more advanced and extensive after 1 year. Calcified foci were found only after 60 months. Various vascular changes such as vascular thickening and thrombosis suggested ischemic insult to the brain as a late effect of radiation injury. The results of this study suggest that the immature brain may be more sensitive to radiation than is the adult brain, and that the manifestations of radiation-induced injury depend on the time elapsed after irradiation. (author)

  20. Radiation-induced bystander effects: Are they good bad or both?

    International Nuclear Information System (INIS)

    Le Guen, B.; Lallemand, J.; Averbeck, D.; Chetioui, A.; Gardes-Albert, M.; Mothersill, C.; Gourmelon, P.; Benderitter, M.; Chevillard, S.; Martin, M.; Verrelle, P.

    2004-01-01

    The different contributions are as follow: the current events on the cellular responses to irradiation ( part one and two); From physico-chemistry to radiobiology: new knowledge (part one and two); Radiation-induced bystander effects: are they good bad or both; recognition of the multi visceral failure in the acute irradiation syndrome; integrated approach of the tissue carcinogenesis: differential effect sane tissue-tumoral tissue; differential diagnosis of thyroid cancers by the transcriptoma analysis. (N.C.)

  1. Three cases of radiation-induced cancer in oral regions

    International Nuclear Information System (INIS)

    Kawamura, Hiroshi; Shinoki, Kunihiko; Endo, Yoshitaka; Fujita, Yasushi; Hayashi, Susumu

    1985-01-01

    Three cases of radiation-induced cancer in the oral regions were reported with relation to radiation therapy. One was the general radiation-induced cancer following radiotherapy for the hemangioma. The other two cases, which belonged in the B-1 group of Sakai and his coworker's diagnostic criteria for radiation-induced cancer, were those occurring after radiotherapy for the malignant tumors. Due to the relatively high dosage exposure by the patient in the radiotherapy it is necessary to look out the latency of the radiation-induced cancer. After radiotherapy, careful and periodical observation is important for immediate treatment in an early stage for the radiation-induced cancer to have a favorable prognosis. In addition careful observation of the changes after radiotherapy helps in discovering the precancerous lesions from the therapy. For the radiation-induced cancer, surgical treatment would be the best, however, radiation therapy is also effective in certain cases. (author)

  2. Gene expression profiling distinguishes between spontaneous and radiation-induced rat mammary carcinomas

    International Nuclear Information System (INIS)

    Imaoka, Tatsuhiko; Nishimura, Mayumi; Kakinuma, Shizuko; Shimada, Yoshiya; Yamashita, Satoshi; Ushijima, Toshikazu

    2008-01-01

    The ability to distinguish between spontaneous and radiation-induced cancers in humans is expected to improve the resolution of estimated risk from low dose radiation. Mammary carcinomas were obtained from Sprague-Dawley rats that were either untreated (n=45) or acutely γ-irradiated (1 Gy; n=20) at seven weeks of age. Gene expression profiles of three spontaneous and four radiation-induced carcinomas, as well as those of normal mammary glands, were analyzed by microarrays. Differential expression of identified genes of interest was then verified by quantitative polymerase chain reaction (qPCR). Cluster analysis of global gene expression suggested that spontaneous carcinomas were distinguished from a heterogeneous population of radiation-induced carcinomas, though most gene expressions were common. We identified 50 genes that had different expression levels between spontaneous and radiogenic carcinomas. We then selected 18 genes for confirmation of the microarray data by qPCR analysis and obtained the following results: high expression of Plg, Pgr and Wnt4 was characteristic to all spontaneous carcinomas; Tnfsf11, Fgf10, Agtr1a, S100A9 and Pou3f3 showed high expression in a subset of radiation-induced carcinomas; and increased Gp2, Areg and Igf2 expression, as well as decreased expression of Ca3 and noncoding RNA Mg1, were common to all carcinomas. Thus, gene expression analysis distinguished between spontaneous and radiogenic carcinomas, suggesting possible differences in their carcinogenic mechanism. (author)

  3. In vivo evidence for an endothelium-dependent mechanism in radiation-induced normal tissue injury

    Science.gov (United States)

    Rannou, Emilie; François, Agnès; Toullec, Aurore; Guipaud, Olivier; Buard, Valérie; Tarlet, Georges; Mintet, Elodie; Jaillet, Cyprien; Iruela-Arispe, Maria Luisa; Benderitter, Marc; Sabourin, Jean-Christophe; Milliat, Fabien

    2015-01-01

    The pathophysiological mechanism involved in side effects of radiation therapy, and especially the role of the endothelium remains unclear. Previous results showed that plasminogen activator inhibitor-type 1 (PAI-1) contributes to radiation-induced intestinal injury and suggested that this role could be driven by an endothelium-dependent mechanism. We investigated whether endothelial-specific PAI-1 deletion could affect radiation-induced intestinal injury. We created a mouse model with a specific deletion of PAI-1 in the endothelium (PAI-1KOendo) by a Cre-LoxP system. In a model of radiation enteropathy, survival and intestinal radiation injury were followed as well as intestinal gene transcriptional profile and inflammatory cells intestinal infiltration. Irradiated PAI-1KOendo mice exhibited increased survival, reduced acute enteritis severity and attenuated late fibrosis compared with irradiated PAI-1flx/flx mice. Double E-cadherin/TUNEL labeling confirmed a reduced epithelial cell apoptosis in irradiated PAI-1KOendo. High-throughput gene expression combined with bioinformatic analyses revealed a putative involvement of macrophages. We observed a decrease in CD68+cells in irradiated intestinal tissues from PAI-1KOendo mice as well as modifications associated with M1/M2 polarization. This work shows that PAI-1 plays a role in radiation-induced intestinal injury by an endothelium-dependent mechanism and demonstrates in vivo that the endothelium is directly involved in the progression of radiation-induced enteritis. PMID:26510580

  4. Survival Fraction at 2 Gy and γH2AX Expression Kinetics in Peripheral Blood Lymphocytes From Cancer Patients: Relationship With Acute Radiation-Induced Toxicities

    Energy Technology Data Exchange (ETDEWEB)

    Pouliliou, Stamatia E. [Department of Radiotherapy/Oncology, Radiobiology and Radiopathology Unit, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Lialiaris, Theodoros S. [Department of Medical Genetics, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Dimitriou, Thespis [Department of Anatomy, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Giatromanolaki, Alexandra [Department of Pathology, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Papazoglou, Dimitrios [Department of Internal Medicine, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Pappa, Aglaia [Department of Molecular Biology and Genetics, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Pistevou, Kyriaki [Department of Radiotherapy/Oncology, Aristotle University of Thessalonica, Thessalonica (Greece); Kalamida, Dimitra [Department of Radiotherapy/Oncology, Radiobiology and Radiopathology Unit, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece); Koukourakis, Michael I., E-mail: targ@her.forthnet.gr [Department of Radiotherapy/Oncology, Radiobiology and Radiopathology Unit, School of Health Sciences, Democritus University of Thrace, Alexandroupolis (Greece)

    2015-07-01

    Purpose: Predictive assays for acute radiation toxicities would be clinically relevant in radiation oncology. We prospectively examined the predictive role of the survival fraction at 2 Gy (SF2) and of γH2AX (double-strand break [DSB] DNA marker) expression kinetics in peripheral blood mononuclear cells (PBMCs) from cancer patients before radiation therapy. Methods and Materials: SF2 was measured with Trypan Blue assay in the PBMCs from 89 cancer patients undergoing radiation therapy at 4 hours (SF2{sub [4h]}) and 24 hours (SF2{sub [24h]}) after ex vivo irradiation. Using Western blot analysis and band densitometry, we further assessed the expression of γH2AX in PBMC DNA at 0 hours, 30 minutes, and 4 hours (33 patients) and 0 hour, 4 hours, and 24 hours (56 patients), following ex vivo irradiation with 2 Gy. Appropriate ratios were used to characterize each patient, and these were retrospectively correlated with early radiation therapy toxicity grade. Results: The SF2{sub (4h)} was inversely correlated with the toxicity grade (P=.006). The γH2AX-ratio{sub (30min)} (band density of irradiated/non-irradiated cells at 30 minutes) revealed, similarly, a significant inverse association (P=.0001). The DSB DNA repair rate from 30 minutes to 4 hours, calculated as the relative RγH2AX-ratio (γH2AX-ratio{sub (4h)}/γH2AX-ratio{sub (30min)}) showed a significant direct association with high toxicity grade (P=.01). Conclusions: Our results suggest that SF2 is a significant radiation sensitivity index for patients undergoing radiation therapy. γH2AX Western blot densitometry analysis provided 2 important markers of normal tissue radiation sensitivity. Low γH2AX expression at 30 minutes was linked with high toxicity grade, suggesting that poor γH2AX repair activity within a time frame of 30 minutes after irradiation predicts for poor radiation tolerance. On the other hand, rapid γH2AX content restoration at 4 hours after irradiation, compatible with

  5. Survival Fraction at 2 Gy and γH2AX Expression Kinetics in Peripheral Blood Lymphocytes From Cancer Patients: Relationship With Acute Radiation-Induced Toxicities

    International Nuclear Information System (INIS)

    Pouliliou, Stamatia E.; Lialiaris, Theodoros S.; Dimitriou, Thespis; Giatromanolaki, Alexandra; Papazoglou, Dimitrios; Pappa, Aglaia; Pistevou, Kyriaki; Kalamida, Dimitra; Koukourakis, Michael I.

    2015-01-01

    Purpose: Predictive assays for acute radiation toxicities would be clinically relevant in radiation oncology. We prospectively examined the predictive role of the survival fraction at 2 Gy (SF2) and of γH2AX (double-strand break [DSB] DNA marker) expression kinetics in peripheral blood mononuclear cells (PBMCs) from cancer patients before radiation therapy. Methods and Materials: SF2 was measured with Trypan Blue assay in the PBMCs from 89 cancer patients undergoing radiation therapy at 4 hours (SF2 [4h] ) and 24 hours (SF2 [24h] ) after ex vivo irradiation. Using Western blot analysis and band densitometry, we further assessed the expression of γH2AX in PBMC DNA at 0 hours, 30 minutes, and 4 hours (33 patients) and 0 hour, 4 hours, and 24 hours (56 patients), following ex vivo irradiation with 2 Gy. Appropriate ratios were used to characterize each patient, and these were retrospectively correlated with early radiation therapy toxicity grade. Results: The SF2 (4h) was inversely correlated with the toxicity grade (P=.006). The γH2AX-ratio (30min) (band density of irradiated/non-irradiated cells at 30 minutes) revealed, similarly, a significant inverse association (P=.0001). The DSB DNA repair rate from 30 minutes to 4 hours, calculated as the relative RγH2AX-ratio (γH2AX-ratio (4h) /γH2AX-ratio (30min) ) showed a significant direct association with high toxicity grade (P=.01). Conclusions: Our results suggest that SF2 is a significant radiation sensitivity index for patients undergoing radiation therapy. γH2AX Western blot densitometry analysis provided 2 important markers of normal tissue radiation sensitivity. Low γH2AX expression at 30 minutes was linked with high toxicity grade, suggesting that poor γH2AX repair activity within a time frame of 30 minutes after irradiation predicts for poor radiation tolerance. On the other hand, rapid γH2AX content restoration at 4 hours after irradiation, compatible with efficient DSB repair ability

  6. Radiation-Induced Bystander Response: Mechanism and Clinical Implications

    Science.gov (United States)

    Suzuki, Keiji; Yamashita, Shunichi

    2014-01-01

    Significance: Absorption of energy from ionizing radiation (IR) to the genetic material in the cell gives rise to damage to DNA in a dose-dependent manner. There are two types of DNA damage; by a high dose (causing acute or deterministic effects) and by a low dose (related to chronic or stochastic effects), both of which induce different health effects. Among radiation effects, acute cutaneous radiation syndrome results from cell killing as a consequence of high-dose exposure. Recent advances: Recent advances in radiation biology and oncology have demonstrated that bystander effects, which are emerged in cells that have never been exposed, but neighboring irradiated cells, are also involved in radiation effects. Bystander effects are now recognized as an indispensable component of tissue response related to deleterious effects of IR. Critical issues: Evidence has indicated that nonapoptotic premature senescence is commonly observed in various tissues and organs. Senesced cells were found to secrete various proteins, including cytokines, chemokines, and growth factors, most of which are equivalent to those identified as bystander factors. Secreted factors could trigger cell proliferation, angiogenesis, cell migration, inflammatory response, etc., which provide a tissue microenvironment assisting tissue repair and remodeling. Future directions: Understandings of the mechanisms and physiological relevance of radiation-induced bystander effects are quite essential for the beneficial control of wound healing and care. Further studies should extend our knowledge of the mechanisms of bystander effects and mode of cell death in response to IR. PMID:24761341

  7. Protective Effect of HSP25 on Radiation Induced Tissue Damage

    International Nuclear Information System (INIS)

    Lee, Hae-June; Lee, Yoon-Jin; Kwon, Hee-Choong; Bae, Sang-Woo; Lee, Yun-Sil; Kim, Sung Ho

    2007-01-01

    Control of cancer by irradiation therapy alone or in conjunction with combination chemotherapy is often limited by organ specific toxicity. Ionizing irradiation toxicity is initiated by damage to normal tissue near the tumor target and within the transit volume of radiotherapy beams. Irradiation-induced cellular, tissue, and organ damage is mediated by acute effects, which can be dose limiting. A latent period follows recovery from the acute reaction, then chronic irradiation fibrosis (late effects) pose a second cause of organ failure. HSP25/27 has been suggested to protect cells against apoptotic cell death triggered by hyperthermia, ionizing radiation, oxidative stress, Fas ligand, and cytotoxic drugs. And several mechanisms have been proposed to account for HSP27-mediated apoptotic protection. However radioprotective effect of HSP25/27 in vivo system has not yet been evaluated. The aim of this study was to evaluate the potential of exogenous HSP25 expression, as delivered by adenoviral vectors, to protect animal from radiation induced tissue damage

  8. Role of neurotensin in radiation-induced hypothermia in rats

    International Nuclear Information System (INIS)

    Kandasamy, S.B.; Hunt, W.A.; Harris, A.H.

    1991-01-01

    The role of neurotensin in radiation-induced hypothermia was examined. Intracerebroventricular (ICV) administration of neurotensin produced dose-dependent hypothermia. Histamine appears to mediate neurotensin-induced hypothermia because the mast cell stabilizer disodium cromoglycate and antihistamines blocked the hypothermic effects of neurotensin. An ICV pretreatment with neurotensin antibody attenuated neurotensin-induced hypothermia, but did not attenuate radiation-induced hypothermia, suggesting that radiation-induced hypothermia was not mediated by neurotensin

  9. Murine strain differences and the effects of zinc on cadmium concentrations in tissues after acute cadmium exposure

    Energy Technology Data Exchange (ETDEWEB)

    King, L.M. [ARS USDA, Germplasm and Gamete Physiology Lab., Beltsville, MD (United States); Anderson, M.B. [Dept. of Anatomy, Tulane Univ. School of Medicine, New Orleans, LA (United States); Sikka, S.C. [Dept. of Urology, Tulane Univ. School of Medicine, New Orleans, LA (United States); George, W.J. [Dept. of Pharmacology, Tulane Univ. School of Medicine, New Orleans, LA (United States)

    1998-10-01

    The role of strain differences in cadmium tissue distribution was studied using sensitive (129/J) and resistant (A/J) mice. These murine strains have previously been shown to differ in their susceptibility to cadmium-induced testicular toxicity. Cadmium concentration was measured in testis, epididymis, seminal vesicle, liver, and kidney at 24 h after cadmium chloride exposure (4, 10, and 20 {mu}mol/kg CdCl{sub 2}). The 129/J mice exhibited a significant increase in cadmium concentration in testis, epididymis, and seminal vesicle at all cadmium doses used, compared to A/J mice. However, cadmium concentrations in liver and kidney were not different between the strains, at any dose, indicating that cadmium uptake is similar in these organs at 24 h. These murine strains demonstrate similar hepatic and renal cadmium uptake but significantly different cadmium accumulation in the reproductive organs at 24 h. The mechanism of the protective effect of zinc on cadmium toxicity was studied by assessing the impact of zinc acetate (ZnAc) treatment on cadmium concentrations in 129/J mice after 24 h. Zinc pretreatment (250 {mu}mol/kg ZnAc), given 24 h prior to 20 {mu}mol/kg CdCl{sub 2} administration, significantly decreased the amount of cadmium in the testis, epididymis, and seminal vesicle of 129/J mice, and significantly increased the cadmium content of the liver after 24 h. Cadmium levels in the kidney were unaffected at this time. Zinc pretreatment also prevented the cadmium-induced decrease in testicular sperm concentration and epididymal sperm motility seen in 129/J mice. These findings suggest that the differences in the two murine strains may be attributed partly to the differential accumulation of cadmium in murine gonads. This may be caused by strain differences in the specificity of cadmium transport mechanisms. The protective role of zinc in cadmium-induced testicular toxicity in the sensitive strain may be due to an interference in the cadmium uptake by susceptible

  10. Radiation-induced bone neoplasma in facial cranium

    Energy Technology Data Exchange (ETDEWEB)

    Zomer-Drozda, J; Buraczewska-Lipinska, H; Buraczewski, J [Instytut Onkologii, Warsaw (Poland)

    1976-01-01

    Radiation-induced bone neoplasms in the region of facial cranium account for about 40% of all radiation-induced tumours of bones, although the number of cases with lesions irradiated in this area is proportionally much lower than the number of cases treated with radiotherapy in other parts of the body. Four personal cases of radiation-induced tumours with complicated course are reported. Attention is called to the value of radiological investigations in the diagnosis of bone diseases and in differential diagnosis of radiation-induced tumours of bones.

  11. Possible mechanisms of chromosomal aberrations: VII. Comparative dynamics of sister chromatid disjunction and realization of radiation-induced chromosomal aberrations during mitosis

    International Nuclear Information System (INIS)

    Lebedeva, L.I.; Akhmamet'eva, E.M.

    1994-01-01

    An increase in radiation-induced chromosomal aberrations during c-metaphase sister chromatid disjunction was demonstrated in murine bone marrow cells exposed to a total γ-irradiation at 0.5 Gy. Caffeine (Cf) treatment during mitosis partially suppressed the chromatid disjunction rate and increased the number of radiation-induced aberrations in this mitosis. Nalidixic acid (NA) treatment of c-metaphase cells completely suppressed chromatid disjunction and the realization of induced aberrations. Topoisomerase 2 was assumed to be involved during mitosis in both processes

  12. Radiation-induced creep and swelling

    International Nuclear Information System (INIS)

    Heald, P.T.

    1977-01-01

    The physical basis for radiation induced creep and swelling is reviewed. The interactions between the point defects and dislocations are recalled since these interactions are ultimately responsible for the observable deformation phenomena. Both the size misfit interaction and the induced inhomogeneity interaction are considered since the former gives rise to irradiation swelling while the latter, which depends on both internal and external stresses, results in irradiation creep. The defect kinetics leading to the deformation processes are discussed in terms of chemical rate theory. The rate equations for the spatially averaged interstitial and vacancy concentrations are expressed in terms of the microstructural sink strengths and the solution of these equations leads to general expressions for the deformation rates

  13. Studies on radiation-induced graft polymerization

    International Nuclear Information System (INIS)

    Omichi, Hideki

    1978-09-01

    Radiation-induced graft polymerization is used extensively to improve physical properties of polymers, but few processes are now commercialized. The reason for this is partly inadequate basic research on the reaction and partly the difficulty in developing the grafting process with large radiation source. Firstly, new techniques are proposed of studying kinetics of the graft polymerization in heterogeneous system. Based on the grafting yield, the molecular weight of graft chains, and the amount of radicals given by ESR and activation analysis, kinetic parameters are obtained and the reaction mechanism of grafting process is discussed. Secondly, the development of grafting process of poly (vinyl chloride)-butadiene is described. By study of the reaction, process design, construction and operation of the pilot plant, and economic analysis of the process, this process with 60 Co gamma ray sources is shown to be industrially promising. (author)

  14. Radiation-induced emulsion polymerization of tetrafluoroethylene

    International Nuclear Information System (INIS)

    Suwa, Takeshi

    1979-10-01

    The radiation-induced emulsifier-free emulsion polymerization of tetrafluoroethylene (TFE) has been studied at initial pressure 2 - 25 kg/cm 2 and temperature 30 0 - 110 0 C for dose rate 0.57 x 10 4 - 3.0 x 10 4 rad/hr. Polytetrafluoroethylene (PTFE), a hydrophobic polymer, forms as a stable latex in the absence of an emulsifier. Stability of the latex is governed by the dose rate/TFE pressure ratio; it increases with sufficient TFE monomer. PTFE particles produced in this polymerization system are stable due to the carboxyl end groups and adsorption of OH - and HF on the particles. PTFE latex of molecular weight higher than 2 x 10 7 is obtained by addition of a radical scavenger such as hydroquinone. The molecular weight of PTFE can be measured from the heat of crystallization conveniently with high reliability, which was found in the course of study on the melting and crystallization behavior. (author)

  15. Radiation-induced mutations and plant breeding

    International Nuclear Information System (INIS)

    Naqvi, S.H.M.

    1985-01-01

    Ionizing radiation could cause genetic changes in an organism and could modify gene linkages. The induction of mutation through radiation is random and the probability of getting the desired genetic change is low but can be increased by manipulating different parameters such as dose rate, physical conditions under which the material has been irradiated, etc. Induced mutations have been used as a supplement to conventional plant breeding, particularly for creating genetic variability for specific characters such as improved plant structure, pest and disease resistance, and desired changes in maturity period; more than 200 varieties of crop plants have been developed by this technique. The Pakistan Atomic Energy Commission has used this technique fruitfully to evolve better germplasm in cotton, rice, chickpea, wheat and mungbean; some of the mutants have become popular commercial varieties. This paper describes some uses of radiation induced mutations and the results achieved in Pakistan so far

  16. Radiation-induced mutations in mammals

    International Nuclear Information System (INIS)

    Ehling, U.H.

    1993-01-01

    The aims of the proposed project are to provide a better basis for extrapolation of animal data to man. Genetic endpoint, strain and species comparisons are made, which will provide critical experimental data regarding strategies in extrapolating laboratory animal data to man. Experiments were conducted to systematically compare the spontaneous and radiation-induced mutation rates for recessive specific-locus, dominant cataract and enzyme activity alleles in the mouse as well as a comparison of the mutation rate in the mouse and hamster for dominant cataract and enzyme activity alleles. The comparison of the radiation-dose response for recessive specific-locus and dominant cataract mutations are extended. Selected mutations are characterized at the genetic, biochemical and molecular levels. (R.P.) 5 refs., 3 tabs

  17. Radiation-induced mutation at minisatellite loci

    International Nuclear Information System (INIS)

    Dubrova, Y.E.; Nesterov, V.N.; Krouchinsky, N.G.

    1997-01-01

    We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of γ-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure 137 Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed

  18. Ionizing radiation-induced cell death

    International Nuclear Information System (INIS)

    Szumiel, I.

    1994-01-01

    Selected aspects of radiation-induced cell death, connected with signal transduction pathways are reviewed. Cell death is defined as insufficiency of the cellular signal transducing system to maintain the cell's physiological functions. The insufficiency may be due to impaired signal reception and/or transduction, lack or erroneous transcription activation, and eventual cellular ''misexpression'' of the signal. The molecular basis of this insufficiency would be damage to genomic (but also other cellular) structures and closing of specific signalling pathways or opening of others (like those leading to apoptosis). I describe experimental data that suggest an important role of RAS/NFI and p53/p105 Rb proteins in cell cycle control-coupled responses to DNA damage. (Author)

  19. An integrated model for radiation induced cancer

    International Nuclear Information System (INIS)

    Hall, E.J.; Varma, M.

    1994-01-01

    Risk estimates for radiation induced cancer are based on epidemiological data, principally the Japanese A bomb survivors. These estimates for radiation are better known than for any other environmental pollutant, but they do not relate directly to exposure to low doses and low dose rate. Recent rapid advances in molecular genetics, coupled with steady gains in cellular biology, radiation physics and chemistry led to the notion that the time may not be far off when it may be possible to arrive at human cancer risk estimates entirely from laboratory data. Whether risk estimates based on laboratory data will ever replace estimates based on epidemiological studies is an open question. What is clear is that laboratory data can supplement the present risk estimates by providing information on the relative effectiveness of high LET radiations, the importance of dose rate and dose protraction, and by identifying subpopulations which are unusually sensitive or resistant to radiation carcinogenesis. (author)

  20. Radiation-induced segregation in model alloys

    Science.gov (United States)

    Ezawa, T.; Wakai, E.; Oshima, R.

    2000-12-01

    The dependence of the size factor of solutes on radiation-induced segregation (RIS) was studied. Ni-Si, Ni-Co, Ni-Cu, Ni-Mn, Ni-Pd, and Ni-Nb binary solid solution alloys were irradiated with electrons in a high voltage electron microscope at the same irradiation conditions. A focused beam and a grain boundary were utilized to generate a flow of point defects to cause RIS. From the concentration profile obtained by an energy dispersive X-ray analysis, the amount of RIS was calculated. The amount of RIS decreased as the size of the solute increased up to about 10%. However, as the size increased further, the amount of RIS increased. This result shows that RIS is not simply determined by the size effect rule.

  1. Radiation-induced grafting onto wool

    International Nuclear Information System (INIS)

    Muller-Schulte, D.

    1979-10-01

    Radiation-induced grafting tests were done on single wool fibres. Different vinyl monomers were used for this purpose and they were grafted in twenty different solvents which were selected for their swelling effiency and solvent parameters. The tests were done once with and once without the addition of water. The presence of water causes the polymer uptake to increase considerably. Formic acid/methanol and methanol were found to be the most suitable solvent systems, as they have the highest hydrogen-bond interaction effiency. The moisture uptake of wool depends on the hydrophily and hydrophoby of the grafted polymers. The single-fibre tests serve as a basis for analogous grafting tests on wool fabrics. The permanent- press was improved by graftng with hydrophoric polymers and polymers with a high glass-transition temperature [af

  2. Radiation-induced electron migration along DNA

    International Nuclear Information System (INIS)

    Fuciarelli, A.F.; Sisk, E.C.; Miller, J.H.; Zimbrick, J.D.

    1994-04-01

    Radiation-induced electron migration along DNA is a mechanism by which randomly produced stochastic energy deposition events can lead to nonrandom types of damage along DNA manifested distal to the sites of the initial energy deposition. Electron migration along DNA is significantly influenced by the DNA base sequence and DNA conformation. Migration along 7 base pairs in oligonucleotides containing guanine bases was observed for oligonucleotides irradiated in solution which compares to average migration distances of 6 to 10 bases for Escherichia coli DNA irradiated in solution and 5.5 base pairs for Escherichia coli DNA irradiated in cells. Evidence also suggests that electron migration can occur preferentially in the 5' to 3' direction along DNA. Our continued efforts will provide information regarding the contribution of electron transfer along DNA to formation of locally multiply damaged sites created in DNA by exposure to ionizing radiation

  3. Acute and chronic in vivo effects of exposure to nicotine and propylene glycol from an E-cigarette on mucociliary clearance in a murine model.

    Science.gov (United States)

    Laube, Beth L; Afshar-Mohajer, Nima; Koehler, Kirsten; Chen, Gang; Lazarus, Philip; Collaco, Joseph M; McGrath-Morrow, Sharon A

    2017-04-01

    To determine the effect of an acute (1 week) and chronic (3 weeks) exposure to E-cigarette (E-cig) emissions on mucociliary clearance (MCC) in murine lungs. C57BL/6 male mice (age 10.5 ± 2.4 weeks) were exposed for 20 min/day to E-cigarette aerosol generated by a Joyetech 510-T ® E-cig containing either 0% nicotine (N)/propylene glycol (PG) for 1 week (n = 6), or 3 weeks (n = 9), or 2.4% N/PG for one week (n = 6), or 3 weeks (n = 9), followed by measurement of MCC. Control mice (n = 15) were not exposed to PG alone, or N/PG. MCC was assessed by gamma camera following aspiration of 99m technetium aerosol and was expressed as the amount of radioactivity removed from both lungs over 6 hours (MCC6hrs). Venous blood was assayed for cotinine levels in control mice and in mice exposed for 3-weeks to PG alone and N/PG. MCC6hrs in control mice and in mice acutely exposed to PG alone and N/PG was similar, averaging (±1 standard deviation) 8.6 ± 5.2%, 7.5 ± 2.8% and 11.2 ± 5.9%, respectively. In contrast, chronic exposure to PG alone stimulated MCC6hrs (17.2 ± 8.0)% and this stimulation was significantly blunted following chronic exposure to N/PG (8.7 ± 4.6)% (p < .05). Serum cotinine levels were <0.5 ng/ml in control mice and in mice exposed to PG alone, whereas, N/PG exposed mice averaged 14.6 ± 12.0 ng/ml. In this murine model, a chronic, daily, 20 min-exposure to N/PG, but not an acute exposure, slowed MCC, compared to exposure to PG alone and led to systemic absorption of nicotine.

  4. Radiation-induced premature menopause: a misconception

    International Nuclear Information System (INIS)

    Madsen, Berit L.; Giudice, Linda; Donaldson, Sarah S.

    1995-01-01

    Purpose: To disprove the common view that women who have undergone irradiation to fields excluding the pelvis are at risk for radiation-induced premature menopause, we reviewed menstrual function and fertility among women treated with subtotal lymphoid irradiation for Hodgkin's Disease. Methods and Materials: Treatment and follow-up records of all women less than age 50 at the time of diagnosis of Stage I or II supradiaphragmatic Hodgkin's Disease, treated with subtotal lymphoid irradiation alone and enrolled in radiotherapy trials from 1967 to 1985, were reviewed. In addition, patients were surveyed regarding their menstrual status and fertility history. Results: Thirty-six women, aged 10 to 40 years, with normal menstrual function at the time of Hodgkin's diagnosis, were identified. Mean follow-up was 14 years, with a range of 1.25-22.75 years. The average radiation dose to mantle and paraaortic fields was 40-44 Gy; the calculated scatter radiation dose to the pelvis at the ovaries was 3.2 Gy. There were 38 pregnancies in 18 women; all offspring are normal. One of 36 women (2.7%) experienced premature menopause. The reported rate of premature menopause in women who have not undergone irradiation is 1-3%; not significantly different than the rate in our study. There is a syndrome whereby antibodies to several endocrine organs occur (including the ovary), which is associated with premature ovarian failure. This syndrome may be associated with prior radiation to the thyroid, such as that given by mantle-irradiation for Hodgkin's Disease. We report such a case. Conclusion: There is little risk of premature menopause in women treated with radiation fields that exclude the pelvis. Women with presumed radiation-induced premature menopause warrant an evaluation to exclude other causes of ovarian failure, such as autoimmune disorders

  5. Radiation induced diffusion as a method to protect surface

    International Nuclear Information System (INIS)

    Baumvol, I.J.R.

    1980-01-01

    Radiation induced diffusion forms a coating adeherent and without interface on the surface of metalic substrates. This coating improves the behaviour of metal to corrosion and abrasion. The effect of radiation induced diffusion of tin and calcium on pure iron surface is described and analyzed in this work. (author) [pt

  6. Radiation induced changes in the airway - anaesthetic implications ...

    African Journals Online (AJOL)

    Radiation induced changes in the airway - anaesthetic implications: case report. Mallika Balakrishnan, Renju Kuriakose, Rachel Cherian Koshy. Abstract. Radiation induces a variety of changes in the airway that can potentially lead to difficult intubation. Osteoradionecrosis (ORN) of the mandible, a severe consequence of ...

  7. Radiation-induced xerostomia in a patient with nasopharyngeal ...

    African Journals Online (AJOL)

    OBJECTIVE: This study reports a case of radiation-induced xerstomia in a patient with nasopharyngeal cancer, to emphasize the need for prompt oral care to prevent untoward effects of xerostomia and to improve patients' quality of life. CASE REPORT: A 60 year old man diagnosed of radiation-induced xerostomia, after 6 ...

  8. Effect of heme oxygenase-1 on radiation-induced skin injury

    International Nuclear Information System (INIS)

    Song Chuanjun; Meng Xingjun; Xie Ling; Chen Qing; Zhou Jundong; Zhang Shuyu; Wu Jinchang

    2012-01-01

    Objective: To investigate the effect of heme oxygenase-1 (HO-1) on the acute radiation-induced skin injury by gene transfer. Methods: Thirty-three male SD rats were randomly divided into three groups as PBS-injected group, Ad-EGFP-injected group and Ad-HO-1-injected group (n=11). In each group, three rats were used for determining the expression of target gene and the other rats were irradiated on the buttock skin with 40 Gy electron beam generated by a linear accelerator. Immediately after irradiation, rats were administered with a subcutaneous injection of PBS, Ad-EGFP or Ad-HO-1, respectively. Subsequently, the skin reactions were measured twice a week using the semi-quantitative skin injury scale. Results: The strong positive expression of HO-1 was observed in subcutaneous dermal tissue after injection of Ad-HO-1. Compared to the PBS-injected group or the Ad-EGFP-injected group, a significant mitigation of skin injury was observed in Ad-HO-1-injected mice 14 d after irradiation (q=0.000-0.030, P<0.05). Conclusions: HO-1 could significantly mitigate radiation-induced acute skin injury and Ad-HO-1 could be used to treat radiation-induced skin injury. (authors)

  9. Epidemiology of Acute Q Fever, Scrub Typhus, and Murine Typhus, and Identification of Their Clinical Characteristics Compared to Patients with Acute Febrile Illness in Southern Taiwan

    Directory of Open Access Journals (Sweden)

    Chung-Hsu Lai

    2009-05-01

    Conclusion: In southern Taiwan, acute Q fever is the most common rickettsiosis. QSM diseases should be suspected in febrile patients who present with relative bradycardia, hepatomegaly, and elevated serum aminotransferases, but without leukocytosis.

  10. Radiation-induced cancer in Japan

    International Nuclear Information System (INIS)

    Yamashita, Shoji; Sekizuka, Eiichi; Yamashita, Hisao; Takami, Akira; Kubo, Atsushi

    2001-01-01

    Results of two questionnaire surveys on radiation-induced malignant tumors conducted in 1977 and 1984 in Japan are briefly summarized. A total of 234 universities and general hospitals (139 in 1977, and 95 in 1984) responded and provided data from 1945 to 1977 and from 1978 to 1984. The number of patients with benign disease who developed secondary malignant tumors following radiation therapy was 150 in the first survey (1977) and 86 in the second survey (1984). The underlying benign diseases of these patients included tuberculous lymphadenitis, skin disease, hemangioma, and thyroid disease, and the most frequent radiation-induced malignant tumors in these patients were malignant tumors of the pharynx (80), cancer of the larynx (26), malignant tumors of the thyroid gland (22), cancer of the esophagus (219), and skin cancer (21). In patients with head and neck diseases the highest correlation between underlying benign disease and radiation-induced malignant tumors was between cervical tuberculous lymphadenitis and tumors of the pharynx (67 patients), followed by cancer of the larynx (19), and malignant tumors of the thyroid gland (11). There were also correlations between thyroid disease and malignant tumors of the thyroid gland (8 patients), hemangioma and skin cancer (7), and skin disease and skin cancer (8). The ratio of the observed values to predicted values (O/E ratio) in these patients was highest for cancer of the pharynx (118), followed by cancer of the parotid gland (42), skin cancer (31), cancer of the esophagus (22), malignant tumors of the thyroid gland (21), and cancer of the larynx (16). The number of patients with malignant tumors who developed secondary malignant tumors following radiation therapy was 140 in 1977 and 108 in 1984, and the underlying malignant tumors in these patients included tumors of the uterus (106), breast (32), and head and neck (80). The most frequent secondary malignant tumors were soft tissue tumors, followed by leukemia, and

  11. Evaluating the role of mitochondrial DNA variation to the genetic predisposition to radiation-induced toxicity

    International Nuclear Information System (INIS)

    Fachal, Laura; Mosquera-Miguel, Ana; Gómez-Caamaño, Antonio; Sánchez-García, Manuel; Calvo, Patricia; Lobato-Busto, Ramón; Salas, Antonio; Vega, Ana

    2014-01-01

    Background and purpose: Mitochondrial DNA common variants have been reported to be associated with the development of radiation-induced toxicity. Using a large cohort of patients, we aimed to validate these findings by investigating the potential role of common European mitochondrial DNA SNPs (mtSNPs) to the development of radio-toxicity. Material and methods: Overall acute and late toxicity data were assessed in a cohort of 606 prostate cancer patients by means of Standardized Total Average Toxicity (STAT) score. We carried out association tests between radiation toxicity and a selection of 15 mtSNPs (and the haplogroups defined by them). Results: Statistically significant association between mtSNPs and haplogroups with toxicity could not be validated in our Spanish cohort. Conclusions: The present study suggests that the mtDNA common variants analyzed are not associated with clinically relevant increases in risk of overall radiation-induced toxicity in prostate cancer patients

  12. A case showing effective radiotherapy for a radiation-induced glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, Kimiko; Inamura, Takanori; Nakamizo, Akira; Ikezaki, Kiyonobu; Inoha, Satoshi; Nakamura, Kazumasa; Matsuzaki, Akinobu; Fukui, Masashi [Kyushu Univ., Fukuoka (Japan). Graduate School of Medical Sciences

    2001-07-01

    Radiation-induced glioblastoma is usually resistant to all treatments. We report a case with radiation-induced glioblastoma, in which radiotherapy was remarkably effective. A 14-year-old female with a history of acute lymphoblastic leukemia, at the age of 7, underwent 15 Gy of radiotherapy to the whole brain. She was admitted to our department due to the development of headache and nausea. Magnetic resonance imaging showed an irregularly enhanced mass in the left frontal lobe. Partial removal of the mass was performed and histological examination showed it to be glioblastoma with a high MIB-1 index. The patient underwent 40 Gy of local radiotherapy and chemotherapy with ACNU and Interferon-{beta} for 2 years. The residual tumor disappeared after the radiotherapy, and her status is still ''complete remission'', 29 months after the onset. (author)

  13. Sucralfate protects intestinal epithelial cells from radiation-induced apoptosis in rats

    International Nuclear Information System (INIS)

    Matsuu-Matsuyama, Mutsumi; Shichijo, Kazuko; Okaichi, Kumio

    2006-01-01

    Radiotherapy for malignant pelvic disease is often followed by acute radiation colitis (ARC). It has been reported that sucralfate treatment has a protective effect against ARC, though the mechanisms of action are unknown. The effects of sucralfate on X-ray radiation-induced apoptosis was studied at 4 Gy in the colonic crypt cells of rats. Sucralfate enemas given prior to radiation resulted in the following: reduction in number of apoptotic colonic crypt cells; reduction in number of caspase-3 positive cells; decreases in p53 accumulation and p21 expression; decreases of Bax/Bcl-2 ratio. The protective effects of sucralfate against ARC may be partially due to the suppression of radiation-induced apoptosis by way of p53 in the colon and the protection of the colonic epithelial stem cell region. (author)

  14. Radiation induced chromosome aberrations and interphase DNA geometry

    International Nuclear Information System (INIS)

    Nasazzi, N.; Di Giorgio, M.; Otero, D.

    1995-01-01

    Ionizing radiation induces DNA double strand breaks (DSBs) and their interaction and illegitimate recombination produces chromosome aberrations. Stable chromosome aberrations comprise inter-chromosomal events (translocations) and intra-chromosomal events (inversions). Assuming DSBs induction and interaction is completely random and neglecting proximity effects, the expected ratio of translocations to inversions is F=86, based on chromosome arm lengths. We analyzed the number of translocations and inversions using G-banding, in 16 lymphocyte cultures from blood samples acutely irradiated with γ-rays (dose range: 0.5Gy-3Gy). Our results give F=13.5, significantly smaller than F=86. Literature data show similar small F values but strongly spread. The excess of inversions could be explained by a 'proximity effect', it means that more proximate DSBs have an extra probability of interaction. Therefore, it is possible to postulate a special chromosome arrangement during irradiation and the subsequent interval. We propose a model where individual chromosomes show spherical confinement with some degree of overlapping and DSBs induction proportional to cross section. We assume a DSBs interaction probability function with cut-off length = 1 μ. We propose that large spread in F data could be due to temporal variation in overlapping and spatial chromosome confinement. (author). 14 refs

  15. Radiation induced early delayed changes in mice brain: a 1h MRS and behavioral evaluation study

    International Nuclear Information System (INIS)

    Gupta, Mamta; Rana, Poonam; Haridas, Seenu; Manda, Kailash; Hemanth Kumar, B.S.; Khushu, Subash

    2014-01-01

    Radiation induced CNS injury can be classified as acute, early delayed and late delayed. Most of the studies suggest that acute injury is reversible whereas early delayed and late delayed injury is irreversible leading to metabolic and cognitive impairment. Extensive research has been carried out on cranial radiation induced early and late delayed changes, there are no reports on whole body radiation induced early and delayed changes. The present study was designed to observe early delayed effects of radiation during whole body radiation exposure. A total of 20 C57 male mice were divided in two groups of 10 animals each. One group was exposed to a dose of 5 Gy whole body radiation through Tele 60 Co irradiation facility with source operating at 2.496 Gy/min, while other group served as sham irradiated control. Behavioral and MR spectroscopy was carried out 3 months post irradiation. Behavioral parameters such as locomotor activity and working memory were evaluated first then followed by MR spectroscopy at 7T animal MRI system. For MRS, voxel was localised in the cortex-hippocampus region of mouse brain. MR spectra were acquired using PRESS sequence, FID was processed using LC model for quantitation. The data showed impaired cognitive functions and altered metabolite levels during early delayed phase of whole body radiation induced injury. In behavioural experiments, there was a significant impairment in the cognitive as well as exploratory functions at 3 months post irradiation in irradiated group as compared to controls. MRS results explained changes in mI, glutamine and glx levels in irradiated animals compared to controls. Altered mI level has been found to be associated with reduced cognitive abilities in many brain disorders including MCI and Alzheimer's disease. The findings of this study suggest that whole body radiation exposure may have long lasting effect on the cognitive performance. (author)

  16. Gamma Radiation-Induced Template Polymerization Technique

    International Nuclear Information System (INIS)

    Siyam, T.

    2005-01-01

    Gamma radiation induced copolymerization of acrylamide sodiumacrylate (AM-AANa) in the presence and absence of the polymer additive was studied at low monomer concentration(1.4M/l). The results showed that the exponents of the dose rate for the polymerization rate was found to be 1.3 and 1.4 in the absence and in the presence of the polymer additive respectively. The molecular weight of the formed polymer increased by addition of the polymer to the system. In the presence of the polymer the comonomers polymerize on the added polymer. In the absence of the added polymer the comonomers polymerize according to the copolymerization process at the initial stage of the copolymerization. While at high conversion the residual comonomers polymerize on the formed macromolecular chains of the produced polymer. These studies showed that the copolymerization in the presence of added polymer is completely template copolymerization while in the absence of the polymer the copolymerization process is only template process with a high conversion

  17. Radiation-Induced Mutation and Crop Improvement

    International Nuclear Information System (INIS)

    Lee, Y. I.; Song, H. S.; Kim, J. S.; Shin, I. C.; Lee, S. J.

    1987-01-01

    Radiation induced mutations have not only been used directly as a cultivar in crop plants, but also indirectly as a genetic resource that is essential to conventional plant breeding. M 1 plant survivals of three rice cultivars treated with gamma rays of 200-350 Gy varied from 30-40%. The survival of the Sawing variety was less sensitive to radiation, but its fertility was more sensitive in comparison with Seomjin and Sponging. Various dwarf or semi-dwarf mutants and early=matured mutants have been selected in the M 2 and M 3 generations of the three rice cultivars irradiated with gamma rays. Other desirable mutants also have been selected, such as high-yielding, high-tailoring and disease-resistant. The genetic nature of most of the selected short calm and earliness mutants was fixed in M 2 or M 3 generations. Dwarfism of IEAR 308 and Monogynol 10 were found to have a single recessive gene. However, the dwarf of IEAR 308 has a recessive deficit phenomenon. The highest genetic heritability of plant height was observed in the cross combination of Monogynol 10 Χ Pawling

  18. Radiation induced mutations for breeding of sorghum

    Energy Technology Data Exchange (ETDEWEB)

    Bretaudeau, A [Rural Polytechnic Inst., Katibougou, Koulikoro (Mali)

    1997-07-01

    Several sorghum cultivars of Mali were irradiated with different doses of gamma rays and compared with the Caudatum types. Radio-sensitivity studies suggested that the local types were less sensitive to radiation than the introduced types. Whereas the local varieties survived dose of 300 Gy, in Caudatum types, seed germination and growth were significantly reduced at 200 Gy. Several agronomically important mutants were obtained among the progeny of the local types. Some of the mutants were shorter and had improved panicle characteristics. Radiation-induced variation was observed in several characters such as plant height, resistance to lodging, plant architecture, drought tolerance, panicle length and compactness, seed size and color, seed quality (viterous or floury) and protein content, glume color and structure, flowering data (early and late maturity), and tillering capacity. One mutant was drought tolerant. Promising mutants were selected and are presently under evaluation in the National List Trials to confirm their potential and future release. Selected variants have been also crossed with local types to obtain promising material. (author). 8 refs, 2 tabs.

  19. Operative treatment of radiation-induced fistulae

    International Nuclear Information System (INIS)

    Balslev, I.; Harling, H.

    1987-01-01

    Out of 136 patients with radiation-induced intestinal complications, 45 had fistulae. Twenty-eight patients had rectovaginal fistulae while the remainder had a total of 13 different types of fistulae. Thirty-seven patients were treated operatively and eight were treated conservatively. Thirty-three patients were submitted to operation for rectal fistulae. Of these, 28 were treated by defunctioning colostomy, three were treated by Hartmann's method and resection and primary anastomosis was carried out in two patients. In the course of the period of observation, 35% of the patients developed new radiation damage. The frequency in the basic material without fistulae was 21% (0.05< p<0.10). Following establishment of defunctioning colostomy on account of rectovaginal fistulae in 25 patients, eight patients developed new fistulae, Significantly more patients with fistulae died of recurrence as compared with patients with other lesions (p<0.01). Defunctioning colostomy in the treatment of rectal fistula is a reasonable form of treatment in elderly patients and in case of recurrence. Younger patients should be assessed in a special department in view of the possibility of a sphincter-preserving procedure following resection of the rectum and restorative anastomosis. (author)

  20. Operative treatment of radiation-induced fistulae

    Energy Technology Data Exchange (ETDEWEB)

    Balslev, I.; Harling, H.

    1987-01-01

    Out of 136 patients with radiation-induced intestinal complications, 45 had fistulae. Twenty-eight patients had rectovaginal fistulae while the remainder had a total of 13 different types of fistulae. Thirty-seven patients were treated operatively and eight were treated conservatively. Thirty-three patients were submitted to operation for rectal fistulae. Of these, 28 were treated by defunctioning colostomy, three were treated by Hartmann's method and resection and primary anastomosis was carried out in two patients. In the course of the period of observation, 35% of the patients developed new radiation damage. The frequency in the basic material without fistulae was 21% (0.05

  1. Radiation-induced cancer in laryngectomized patients

    International Nuclear Information System (INIS)

    Miyahara, Hiroshi; Tsuruta, Yoshihiro; Sato, Takeo; Yoshino, Kunitoshi; Umatani, Katunori

    1991-01-01

    Three patients developed hypopharyngo-cervical esophageal carcinoma, 6.5, 13, and 12 years after total laryngectomy. The first patient had received irradiation (60 Gy) for hypopharyngeal carcinoma. The recurrent tumor was removed with total pharyngolaryngoesophagectomy and reconstruction was performed with a local skin flap. After 6 years and 6 months, she developed progressive dysphagia. A new cervical esophageal skin cancer was diagnosed by pharyngoesophagography and treated. The second patient had had total laryngectomy for laryngeal carcinoma and received irradiation (100 Gy) post-operatively. After 13 years, he developed progressive dysphagia. Pharyngoesophagography revealed cervical esophageal carcinoma. The third patient had received irradiation for laryngeal carcinoma (60 Gy) and underwent total laryngectomy because of recurrence. After 12 years she developed dysphagia, and was treated for hypopharyngeal carcinoma. These three patients seemed to have radiation-induced carcinoma. Patients treated with total laryngectomy and irradiation who later complain of progressive dysphagia should be examined carefully to differentiate between postoperative stenosis due to scarring and a new carcinoma. (author)

  2. Radiation induced mutations for breeding of sorghum

    International Nuclear Information System (INIS)

    Bretaudeau, A.

    1997-01-01

    Several sorghum cultivars of Mali were irradiated with different doses of gamma rays and compared with the Caudatum types. Radio-sensitivity studies suggested that the local types were less sensitive to radiation than the introduced types. Whereas the local varieties survived dose of 300 Gy, in Caudatum types, seed germination and growth were significantly reduced at 200 Gy. Several agronomically important mutants were obtained among the progeny of the local types. Some of the mutants were shorter and had improved panicle characteristics. Radiation-induced variation was observed in several characters such as plant height, resistance to lodging, plant architecture, drought tolerance, panicle length and compactness, seed size and color, seed quality (viterous or floury) and protein content, glume color and structure, flowering data (early and late maturity), and tillering capacity. One mutant was drought tolerant. Promising mutants were selected and are presently under evaluation in the National List Trials to confirm their potential and future release. Selected variants have been also crossed with local types to obtain promising material. (author). 8 refs, 2 tabs

  3. Radiation-induced cranial nerve palsy

    International Nuclear Information System (INIS)

    Berger, P.S.; Bataini, J.P.

    1977-01-01

    Twenty-five patients with 35 cranial nerve palsies were seen at the Fondation Curie during follow-up after radical radiotherapy for head and neck tumors. The twelfth nerve was involved in 19 cases, the tenth in nine, and the eleventh in five; the fifth and second nerves were involved once each and in the same patient. The twelfth nerve was involved alone in 16 patients and the tenth nerve alone in three, with multiple nerves involved in the remaining six patients. The palsy was noted from 12 to 145 months after diagnosis of the tumor. The latency period could be correlated with dose so that the least square fit equation representing NSD vs delay is NSD = 2598--Delay (in months) x 4.6, with a correlation coefficient of -0.58. The distinction between tumor recurrence and radiation-induced nerve palsy is critical. It can often be inferred from the latency period but must be confirmed by observation over a period of time

  4. Ionizing radiation induces stemness in cancer cells.

    Directory of Open Access Journals (Sweden)

    Laura Ghisolfi

    Full Text Available The cancer stem cell (CSC model posits the presence of a small number of CSCs in the heterogeneous cancer cell population that are ultimately responsible for tumor initiation, as well as cancer recurrence and metastasis. CSCs have been isolated from a variety of human cancers and are able to generate a hierarchical and heterogeneous cancer cell population. CSCs are also resistant to conventional chemo- and radio-therapies. Here we report that ionizing radiation can induce stem cell-like properties in heterogeneous cancer cells. Exposure of non-stem cancer cells to ionizing radiation enhanced spherogenesis, and this was accompanied by upregulation of the pluripotency genes Sox2 and Oct3/4. Knockdown of Sox2 or Oct3/4 inhibited radiation-induced spherogenesis and increased cellular sensitivity to radiation. These data demonstrate that ionizing radiation can activate stemness pathways in heterogeneous cancer cells, resulting in the enrichment of a CSC subpopulation with higher resistance to radiotherapy.

  5. Radiation-induced valvular heart disease.

    Science.gov (United States)

    Gujral, Dorothy M; Lloyd, Guy; Bhattacharyya, Sanjeev

    2016-02-15

    Radiation to the mediastinum is a key component of treatment with curative intent for a range of cancers including Hodgkin's lymphoma and breast cancer. Exposure to radiation is associated with a risk of radiation-induced heart valve damage characterised by valve fibrosis and calcification. There is a latent interval of 10-20 years between radiation exposure and development of clinically significant heart valve disease. Risk is related to radiation dose received, interval from exposure and use of concomitant chemotherapy. Long-term outlook and the risk of valve surgery are related to the effects of radiation on mediastinal structures including pulmonary fibrosis and pericardial constriction. Dose prediction models to predict the risk of heart valve disease in the future and newer radiation techniques to reduce the radiation dose to the heart are being developed. Surveillance strategies for this cohort of cancer survivors at risk of developing significant heart valve complications are required. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  6. Pathology of radiation induced lung damage

    International Nuclear Information System (INIS)

    Kawabata, Yoshinori; Murata, Yoshihiko; Ogata, Hideo; Katagiri, Shiro; Sugita, Hironobu; Iwai, Kazuo; Sakurai, Isamu.

    1985-01-01

    We examined pathological findings of radiation induced lung damage. Twenty-three cases are chosen from our hospital autopsy cases for 9 years, which fulfil strict criteria of radiation lung damage. Lung damage could be classified into 3 groups : 1) interstitial pneumonia type (9 cases), 2) intermediate pneumonia type (8 cases), and 3) alveolar pneumonia type (6 cases), according to the degree of intra-luminal exudation. These classification is well correlated with clinical findings. Pathological alveolar pneumonia type corresponds to symptomatic, radiologic ground glass pneumonic shadow. And pathologic interstitial type corresponds to clinical asymptomatic, radiologic reticulo-nodular shadow. From the clinico-pathological view point these classification is reasonable one. Radiation affects many lung structures and showed characteristic feature of repair. Elastofibrosis of the alveolar wall is observed in every cases, obstructive bronchiolitis are observed in 5 cases, and obstructive bronchiolitis in 9 cases. They are remarkable additional findings. Thickening of the interlobular septum, broncho-vascular connective tissue, and pleural layer are observed in every cases together with vascular lesions. (author)

  7. Radiation-induced ηe-modes

    International Nuclear Information System (INIS)

    Shukla, P.K.; Yu, M.Y.

    1990-01-01

    Impurity radiation in a plasma can cause not only static instabilities, but also dynamic instabilities related to the drift and acoustic waves. Radiative instabilities are of much interest because they are associated with relatively high frequency and short wavelength fluctuations, which have been suspected to be responsible for anomalous electron energy transport in tokamak edge plasmas. In this paper, we consider radiation-induced η e instabilities, taking into account electrostatic effects as well as density and temperature inhomogeneities. Also included are the effects of finite gyroradius and dissipation. It is found that the latter can cause strong linear coupling between the modes of interest. The resulting instabilities can have larger growth rates than the static radiative instability. Analytical expressions for the growth rates and instability regimes are given for the limiting cases of practical interest. In particular, it is shown that the η e -mode can couple to both radiation and dissipation to cause resistive instabilities. The parameter regimes of the original radiative as well as the dissipative modes are thereby broadened and shifted because of the interaction. (author) 3 refs

  8. Effects of Pharmacological Inhibition and Genetic Deficiency of Plasminogen Activator Inhibitor-1 in Radiation-Induced Intestinal Injury

    International Nuclear Information System (INIS)

    Abderrahmani, Rym; Francois, Agnes; Buard, Valerie; Benderitter, Marc; Sabourin, Jean-Christophe; Crandall, David L.; Milliat, Fabien

    2009-01-01

    Purpose: To investigate effects of plasminogen activator inhibitor 1 (PAI-1) genetic deficiency and pharmacological PAI-1 inhibition with PAI-039 in a mouse model of radiation-induced enteropathy. Methods and Materials: Wild-type (Wt) and PAI-1 -/- knockout mice received a single dose of 19 Gy to an exteriorized localized intestinal segment. Sham and irradiated Wt mice were treated orally with 1 mg/g of PAI-039. Histological modifications were quantified using a radiation injury score. Moreover, intestinal gene expression was monitored by real-time PCR. Results: At 3 days after irradiation, PAI-039 abolished the radiation-induced increase in the plasma active form of PAI-1 and limited the radiation-induced gene expression of transforming growth factor β1 (TGF-β1), CTGF, PAI-1, and COL1A2. Moreover, PAI-039 conferred temporary protection against early lethality. PAI-039 treatment limited the radiation-induced increase of CTGF and PAI-1 at 2 weeks after irradiation but had no effect at 6 weeks. Radiation injuries were less severe in PAI-1 -/- mice than in Wt mice, and despite the beneficial effect, 3 days after irradiation, PAI-039 had no effects on microscopic radiation injuries compared to untreated Wt mice. Conclusions: A genetic deficiency of PAI-1 is associated with amelioration of late radiation enteropathy. Pharmacological inhibition of PAI-1 by PAI-039 positively impacts the early, acute phase increase in plasma PAI-1 and the associated radiation-induced gene expression of inflammatory/extracellular matrix proteins. Since PAI-039 has been shown to inhibit the active form of PAI-1, as opposed to the complete loss of PAI-1 in the knockout animals, these data suggest that a PAI-1 inhibitor could be beneficial in treating radiation-induced tissue injury in acute settings where PAI-1 is elevated.

  9. Genome wide transcriptome profiling of a murine acute melioidosis model reveals new insights into how Burkholderia pseudomallei overcomes host innate immunity

    Directory of Open Access Journals (Sweden)

    Nathan Sheila

    2010-11-01

    Full Text Available Abstract Background At present, very little is known about how Burkholderia pseudomallei (B. pseudomallei interacts with its host to elicit melioidosis symptoms. We established a murine acute-phase melioidosis model and used DNA microarray technology to investigate the global host/pathogen interaction. We compared the transcriptome of infected liver and spleen with uninfected tissues over an infection period of 42 hr to identify genes whose expression is altered in response to an acute infection. Results Viable B. pseudomallei cells were consistently detected in the blood, liver and spleen during the 42 hr course of infection. Microarray analysis of the liver and spleen over this time course demonstrated that genes involved in immune response, stress response, cell cycle regulation, proteasomal degradation, cellular metabolism and signal transduction pathways were differentially regulated. Up regulation of toll-like receptor 2 (TLR2 gene expression suggested that a TLR2-mediated signalling pathway is responsible for recognition and initiation of an inflammatory response to the acute B. pseudomallei infection. Most of the highly elevated inflammatory genes are a cohort of "core host immune response" genes commonly seen in general inflammation infections. Concomitant to this initial inflammatory response, we observed an increase in transcripts associated with cell-death, caspase activation and peptidoglysis that ultimately promote tissue injury in the host. The complement system responsible for restoring host cellular homeostasis and eliminating intracellular bacteria was activated only after 24 hr post-infection. However, at this time point, diverse host nutrient metabolic and cellular pathways including glycolysis, fatty acid metabolism and tricarboxylic acid (TCA cycle were repressed. Conclusions This detailed picture of the host transcriptional response during acute melioidosis highlights a broad range of innate immune mechanisms that are

  10. Regulatory T Cells Promote β-Catenin–Mediated Epithelium-to-Mesenchyme Transition During Radiation-Induced Pulmonary Fibrosis

    International Nuclear Information System (INIS)

    Xiong, Shanshan; Pan, Xiujie; Xu, Long; Yang, Zhihua; Guo, Renfeng; Gu, Yongqing; Li, Ruoxi; Wang, Qianjun; Xiao, Fengjun; Du, Li; Zhou, Pingkun; Zhu, Maoxiang

    2015-01-01

    Purpose: Radiation-induced pulmonary fibrosis results from thoracic radiation therapy and severely limits radiation therapy approaches. CD4 + CD25 + FoxP3 + regulatory T cells (Tregs) as well as epithelium-to-mesenchyme transition (EMT) cells are involved in pulmonary fibrosis induced by multiple factors. However, the mechanisms of Tregs and EMT cells in irradiation-induced pulmonary fibrosis remain unclear. In the present study, we investigated the influence of Tregs on EMT in radiation-induced pulmonary fibrosis. Methods and Materials: Mice thoraxes were irradiated (20 Gy), and Tregs were depleted by intraperitoneal injection of a monoclonal anti-CD25 antibody 2 hours after irradiation and every 7 days thereafter. Mice were treated on days 3, 7, and 14 and 1, 3, and 6 months post irradiation. The effectiveness of Treg depletion was assayed via flow cytometry. EMT and β-catenin in lung tissues were detected by immunohistochemistry. Tregs isolated from murine spleens were cultured with mouse lung epithelial (MLE) 12 cells, and short interfering RNA (siRNA) knockdown of β-catenin in MLE 12 cells was used to explore the effects of Tregs on EMT and β-catenin via flow cytometry and Western blotting. Results: Anti-CD25 antibody treatment depleted Tregs efficiently, attenuated the process of radiation-induced pulmonary fibrosis, hindered EMT, and reduced β-catenin accumulation in lung epithelial cells in vivo. The coculture of Tregs with irradiated MLE 12 cells showed that Tregs could promote EMT in MLE 12 cells and that the effect of Tregs on EMT was partially abrogated by β-catenin knockdown in vitro. Conclusions: Tregs can promote EMT in accelerating radiation-induced pulmonary fibrosis. This process is partially mediated through β-catenin. Our study suggests a new mechanism for EMT, promoted by Tregs, that accelerates radiation-induced pulmonary fibrosis

  11. Regulatory T Cells Promote β-Catenin–Mediated Epithelium-to-Mesenchyme Transition During Radiation-Induced Pulmonary Fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Shanshan; Pan, Xiujie; Xu, Long; Yang, Zhihua [Beijing Institute of Radiation Medicine, Beijing (China); Guo, Renfeng [Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan (United States); Gu, Yongqing; Li, Ruoxi; Wang, Qianjun; Xiao, Fengjun; Du, Li; Zhou, Pingkun [Beijing Institute of Radiation Medicine, Beijing (China); Zhu, Maoxiang, E-mail: zhumx@nic.bmi.ac.cn [Beijing Institute of Radiation Medicine, Beijing (China)

    2015-10-01

    Purpose: Radiation-induced pulmonary fibrosis results from thoracic radiation therapy and severely limits radiation therapy approaches. CD4{sup +}CD25{sup +}FoxP3{sup +} regulatory T cells (Tregs) as well as epithelium-to-mesenchyme transition (EMT) cells are involved in pulmonary fibrosis induced by multiple factors. However, the mechanisms of Tregs and EMT cells in irradiation-induced pulmonary fibrosis remain unclear. In the present study, we investigated the influence of Tregs on EMT in radiation-induced pulmonary fibrosis. Methods and Materials: Mice thoraxes were irradiated (20 Gy), and Tregs were depleted by intraperitoneal injection of a monoclonal anti-CD25 antibody 2 hours after irradiation and every 7 days thereafter. Mice were treated on days 3, 7, and 14 and 1, 3, and 6 months post irradiation. The effectiveness of Treg depletion was assayed via flow cytometry. EMT and β-catenin in lung tissues were detected by immunohistochemistry. Tregs isolated from murine spleens were cultured with mouse lung epithelial (MLE) 12 cells, and short interfering RNA (siRNA) knockdown of β-catenin in MLE 12 cells was used to explore the effects of Tregs on EMT and β-catenin via flow cytometry and Western blotting. Results: Anti-CD25 antibody treatment depleted Tregs efficiently, attenuated the process of radiation-induced pulmonary fibrosis, hindered EMT, and reduced β-catenin accumulation in lung epithelial cells in vivo. The coculture of Tregs with irradiated MLE 12 cells showed that Tregs could promote EMT in MLE 12 cells and that the effect of Tregs on EMT was partially abrogated by β-catenin knockdown in vitro. Conclusions: Tregs can promote EMT in accelerating radiation-induced pulmonary fibrosis. This process is partially mediated through β-catenin. Our study suggests a new mechanism for EMT, promoted by Tregs, that accelerates radiation-induced pulmonary fibrosis.

  12. Radiation-Induced Alopecia after Endovascular Embolization under Fluoroscopy

    Directory of Open Access Journals (Sweden)

    Vipawee Ounsakul

    2016-01-01

    Full Text Available Radiation-induced alopecia after fluoroscopically guided procedures is becoming more common due to an increasing use of endovascular procedures. It is characterized by geometric shapes of nonscarring alopecia related to the area of radiation. We report a case of a 46-year-old man presenting with asymptomatic, sharply demarcated rectangular, nonscarring alopecic patch on the occipital scalp following cerebral angiography with fistula embolization under fluoroscopy. His presentations were compatible with radiation-induced alopecia. Herein, we also report a novel scalp dermoscopic finding of blue-grey dots in a target pattern around yellow dots and follicles, which we detected in the lesion of radiation-induced alopecia.

  13. Acemannan (a polysaccharides of Aloe vera gel) protects against radiation induced mortality by modulation of immunosuppression

    International Nuclear Information System (INIS)

    Kumar, Sumit; Tiku, Ashu Bhan

    2014-01-01

    Acemannan (poly-acetylated mannose) is an active component of Aloe vera gel and has been reported to have anticancerous, antimicrobial and shown to stimulate the development and proliferation of the hematopoietic cells. The anticancerous properties of acemannan have been attributed to the modulation of immune system rather then cytotoxicity. Therefore objective of the present study was to evaluate radioprotective efficacy of acemannan against radiation induced immune suppression using Swiss albino mice as a model system. For In-vivo studies mice were treated for 7 days orally prior to irradiation (5 Gy). Animals were sacrificed at different time point to study the effect on cellular proliferation, DNA damage, apoptosis and ROS level, cytokines level, antioxidant enzymes, nitric oxide and protein expression. For survival studies mice were treated with acemannan for 7 days pre or post irradiation and survival was monitored for 30 days. Acemannan showed a significant induction of proliferation of splenocytes in radiation treated groups. Beside a decrease in radiation induced ROS and DNA damage resulted in the reduction of apoptosis in murine splenocytes. Acemannan restored the antioxidant enzyme level (catalase, SOD, DTD and GST) and maintained the proper redox status via GSH, in irradiated mice. Further acemannan was shown to induce the hematopoiesis (peripheral lymphocytes cells, spleen colony cells, spleen index) by increasing the level of the pro-hematopoiesis cytokines (IL-1, TNF-α). Being an immunomodulator, acemannan reduced the level of the inflammation (IL-6, nitric oxide). Also the multiple mechanisms operational at cellular and molecule levelled to the reduction of radiation induced mortality of mice in both pre and post-irradiation studies. On the basis of the above results it can be concluded that radioprotective effects of the acemannan was due to its immunomodulatory activity and could have application for radio-therapeutic purposes. (author)

  14. Protective effects of acemannan against radiation induced damage in Swiss albino mice

    International Nuclear Information System (INIS)

    Kumar, Sumit; Tiku, Ashu Bhan

    2013-01-01

    Aloe vera is one of the well known medicinal plant and posses a large no. of beneficial bioactive components like Anthraquinone, C-glycosides, anthrones, emodin, acemannan etc. Acemannan (poly-acetylated mannose) is one of the active component present in aloe vera gel and has anticancerous and antimicrobial properties. It has also been reported to have wound healing properties and has role as immunomodulator. The objective of the present study was to evaluate protective efficacy of acemannan against radiation induced damage in in-vitro and in in-vivo using murine splenocytes and Swiss albino mice as a model system. In vitro studies were done using primary mouse splenocytes cultures and effect of radiation on cell proliferation, viability, ROS, DNA damage and apoptosis were studies using MTT, trypan blue, DCFDA, single cell gel electrophoresis and ladder assay respectively. For in-vivo studies mice were pretreated with different doses of drug for 7 days followed by irradiation (5 Gy). Twenty four hours post-irradiation mice was sacrificed to observe the activity of antioxidant enzymes and level of protein expression. Acemannan showed a significant induction of proliferation of splenocytes in radiation treated groups both in in-vitro and in in-vivo. Beside a decrease in radiation induced ROS and DNA damage was observed in in-vitro system. Acemannan treatment was able to reduce the radiation induced apoptosis by about 50% both in in-vitro and in in-vivo. In in-vivo acemannan helps in the restoration of the antioxidant enzyme level (catalase, SOD, DTD and GST) besides maintaining the proper redox status via GSH, in irradiated mice. In our studies a dose of 50 mg/kg body wt of acemannan showed the best protective effects. On the basis of the above results it could be concluded that acemannan may have radioprotective potential. (author)

  15. Delayed Radiation-Induced Vasculitic Leukoencephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, Philipp J. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Faculty of Medicine, University of Heidelberg, Heidelberg (Germany); Park, Henry S. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Knisely, Jonathan P.S. [Department of Radiation Medicine, North Shore University Hospital, Manhasset, New York (United States); Chiang, Veronica L. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Vortmeyer, Alexander O., E-mail: alexander.vortmeyer@yale.edu [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States)

    2012-05-01

    Purpose: Recently, single-fraction, high-dosed focused radiation therapy such as that administered by Gamma Knife radiosurgery has been used increasingly for the treatment of metastatic brain cancer. Radiation therapy to the brain can cause delayed leukoencephalopathy, which carries its own significant morbidity and mortality. While radiosurgery-induced leukoencephalopathy is known to be clinically different from that following fractionated radiation, pathological differences are not well characterized. In this study, we aimed to integrate novel radiographic and histopathologic observations to gain a conceptual understanding of radiosurgery-induced leukoencephalopathy. Methods and Materials: We examined resected tissues of 10 patients treated at Yale New Haven Hospital between January 1, 2009, and June 30, 2010, for brain metastases that had been previously treated with Gamma Knife radiosurgery, who subsequently required surgical management of a symptomatic regrowing lesion. None of the patients showed pathological evidence of tumor recurrence. Clinical and magnetic resonance imaging data for each of the 10 patients were then studied retrospectively. Results: We provide evidence to show that radiosurgery-induced leukoencephalopathy may present as an advancing process that extends beyond the original high-dose radiation field. Neuropathologic examination of the resected tissue revealed traditionally known leukoencephalopathic changes including demyelination, coagulation necrosis, and vascular sclerosis. Unexpectedly, small and medium-sized vessels revealed transmural T-cell infiltration indicative of active vasculitis. Conclusions: We propose that the presence of a vasculitic component in association with radiation-induced leukoencephalopathy may facilitate the progressive nature of the condition. It may also explain the resemblance of delayed leukoencephalopathy with recurring tumor on virtually all imaging modalities used for posttreatment follow-up.

  16. A case of radiation induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ozawa, Kazuyoshi; Tsuchikawa, Kohzo; Sato, Akira; Kato, Joji (Nippon Dental Univ., Niigata (Japan). School of Dentistry at Niigata)

    1994-06-01

    A case of carcinoma on the right buccal mucosa is presented. The case was suspected to have been induced by irradiation therapy for a carcinoma on the left buccal mucosa. An external radiotherapy, 6-MeV Linac, had been done for the carcinoma on the left buccal mucosa in a 55-year-old female, with single lateral direction from the left to the right in 1977. In 1985, a papillary lesion on the right buccal mucosa was detected, and histological examination revealed a papilloma without atypism. In 1991, as an ulcer on the right upper buccal fold as well as three papillary lesions in the central portion of the right buccal mucosa were found, the patient was referred to our clinic. Microscopical findings were consistent with the early invasive carcinomas. A surgical excision of these whole lesions and skin graft were completed. The criteria of this case for the suspicion of radiation-induced carcinoma were as follows. There was a long latent period of 14 years. The previous dose of irradiation, 60 Gy, was sufficient. The right buccal mucosa was involved in the radiation field. A severe scar on the left cheek resulted from the previous irradiation. Anatomically, there is no evidence of the secondary carcinoma on the right buccal mucosa with the primary carcinoma on the left buccal mucosa. No evidence for recurrence of the tumors on both sides of buccal mucosa has been detected so far. Further observations will be necessary to detect other tumors in the irradiated field later on. (author).

  17. Radiation-induced carotid artery atherosclerosis

    International Nuclear Information System (INIS)

    Gujral, Dorothy M.; Chahal, Navtej; Senior, Roxy; Harrington, Kevin J.; Nutting, Christopher M.

    2014-01-01

    Purpose: Carotid arteries frequently receive significant doses of radiation as collateral structures in the treatment of malignant diseases. Vascular injury following treatment may result in carotid artery stenosis (CAS) and increased risk of stroke and transient ischaemic attack (TIA). This systematic review examines the effect of radiotherapy (RT) on the carotid arteries, looking at the incidence of stroke in patients receiving neck radiotherapy. In addition, we consider possible surrogate endpoints such as CAS and carotid intima-medial thickness (CIMT) and summarise the evidence for radiation-induced carotid atherosclerosis. Materials and methods: From 853 references, 34 articles met the criteria for inclusion in this systematic review. These papers described 9 studies investigating the incidence of stroke/TIA in irradiated patients, 11 looking at CAS, and 14 examining CIMT. Results: The majority of studies utilised suboptimally-matched controls for each endpoint. The relative risk of stroke in irradiated patients ranged from 1.12 in patients with breast cancer to 5.6 in patients treated for head and neck cancer. The prevalence of CAS was increased by 16–55%, with the more modest increase seen in a study using matched controls. CIMT was increased in irradiated carotid arteries by 18–40%. Only two matched-control studies demonstrated a significant increase in CIMT of 36% and 22% (p = 0.003 and <0.001, respectively). Early prospective data demonstrated a significant increase in CIMT in irradiated arteries at 1 and 2 years after RT (p < 0.001 and <0.01, respectively). Conclusions: The incidence of stroke was significantly increased in patients receiving RT to the neck. There was a consistent difference in CAS and CIMT between irradiated and unirradiated carotid arteries. Future studies should optimise control groups

  18. Ferulic acid ameliorates radiation induced duodenal inflammation

    International Nuclear Information System (INIS)

    Das, Ujjal; Manna, Krishnendu; Sengupta, Aaveri; Biswas, Sushobhan; Chakrabarty, Arpita; Dey, Sanjit

    2016-01-01

    Ionizing radiation creates oxidative stress followed by inflammation through reactive oxygen species (ROS) and altering the status of redox sensitive enzymes. In the current study we aimed to evaluate the effect of ferulic acid (FA) on increasing doses of ionizing radiation mediated oxidative stress and inflammation using in vivo murine duodenum. To delineate the hypothesis we exposed mice with 2.5, 5 and 10 Gy gamma radiation doses in presence and absence of the (FA). FA was administered orally at a fixed dose of 50mg/ kg bw for 5 days before radiation exposure. Different techniques such as biochemical assays, immune blot, and microscopic analysis for histopathology, flow cytometry and scanning electron microscopy were employed to achieve the goal

  19. Hazard of the radiation induced thyroid cancer

    International Nuclear Information System (INIS)

    Buglova, Ye.Ye.

    2001-01-01

    The level of thyroid cancer in Belarus before Chernobyl accident was low and made in different age and sex groups 0,03-2,5 (male) and 0,1-3,9 (female) per 100000 correspondingly. Different risk factors, which can influence the thyroid cancer development, are being taken into account. They are the factors of environment (strong external irradiation, long-time irradiation for medical purposes or in result of disaster), endo gen factors (hormonal, reproductive, genetic predisposition), some medicinal preparations and other. The protective effect of vegetable and fish consumption was found out. Among the factors of thyroid cancer development one of the most important is radiation. There is a point of view, which assumes that one of the reasons of thyroid cancer cases increase among the population of developed countries is increase of radiation induced thyroid cancer. The results of first research testify the influence of radiation factor on thyroid cancer development. During the period 1920 -1960 in the USA X-ray therapy was applied for the treatment of different good-quality diseases. Thyroid got in the zone of irradiation during the complex treatment with using of radiation. The results of the research of 1970 revealed that 70% of children with thyroid cancer were exposed to radiation in children's age. The subsequent researches of by-effects from the side of a thyroid at beam therapy of various diseases alongside with the results of the estimation of consequences of inhabitants of Hiroshima and Nagasaki irradiation owing to nuclear bombardment have shown the influence of irradiation of a thyroid on cancer development. High quantity of radio-epidemiological researches was directed to the studying of the consequences of thyroid external irradiation at young age. In all carried out researches the quantity of observed thyroid cancer cases among irradiated people has exceeded number of expected. The influence of thyroid internal irradiation by I-131 at young age was

  20. Indomethacin attenuation of radiation-induced hyperthermia does not modify radiation-induced motor hypoactivity

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, J.L.; Kandasamy, S.B.; Harris, A.H.; Davis, H.D.; Landauer, M.R. [Armed Forces Radiobiology Research Inst., Bethesda, MD (United States)

    1996-09-01

    Exposure of rats to 5-10 Gy of ionizing radiation produces hyperthermia and reduces motor activity. Previous studies suggested that radiation-induced hyperthermia results from a relatively direct action on the brain and is mediated by prostaglandins. To test the hypothesis that hypoactivity may be, in part, a thermoregulatory response to this elevation in body temperature, adult male rats were given indomethacin (0.0, 0.5, 1.0, and 3.0 mg/kg, intraperitoneally), a blocker of prostaglandin synthesis, and were either irradiated (LINAC 18.6 MeV (nominal) high-energy electrons, 10 Gy at 10 Gy/min, 2.8 {mu}sec pulses at 2 Hz) or sham-irradiated. The locomotor activity of all rats was then measured for 30 min in a photocell monitor for distance traveled and number of vertical movements. Rectal temperatures of irradiated rats administered vehicle only were elevated by 0.9{+-}0.2degC at the beginning and the end of the activity session. Although indomethacin, at the two higher doses tested, attenuated the hyperthermia in irradiated rats by 52-75%, it did not attenuate radiation-induced reductions in motor activity. These results indicate that motor hypoactivity after exposure to 10 Gy of high-energy electrons is not due to elevated body temperature or to the increased synthesis of prostaglandins. (author)

  1. Indomethacin attenuation of radiation-induced hyperthermia does not modify radiation-induced motor hypoactivity

    International Nuclear Information System (INIS)

    Ferguson, J.L.; Kandasamy, S.B.; Harris, A.H.; Davis, H.D.; Landauer, M.R.

    1996-01-01

    Exposure of rats to 5-10 Gy of ionizing radiation produces hyperthermia and reduces motor activity. Previous studies suggested that radiation-induced hyperthermia results from a relatively direct action on the brain and is mediated by prostaglandins. To test the hypothesis that hypoactivity may be, in part, a thermoregulatory response to this elevation in body temperature, adult male rats were given indomethacin (0.0, 0.5, 1.0, and 3.0 mg/kg, intraperitoneally), a blocker of prostaglandin synthesis, and were either irradiated (LINAC 18.6 MeV (nominal) high-energy electrons, 10 Gy at 10 Gy/min, 2.8 μsec pulses at 2 Hz) or sham-irradiated. The locomotor activity of all rats was then measured for 30 min in a photocell monitor for distance traveled and number of vertical movements. Rectal temperatures of irradiated rats administered vehicle only were elevated by 0.9±0.2degC at the beginning and the end of the activity session. Although indomethacin, at the two higher doses tested, attenuated the hyperthermia in irradiated rats by 52-75%, it did not attenuate radiation-induced reductions in motor activity. These results indicate that motor hypoactivity after exposure to 10 Gy of high-energy electrons is not due to elevated body temperature or to the increased synthesis of prostaglandins. (author)

  2. Novel features of radiation-induced segregation and radiation-induced precipitation in austenitic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Z., E-mail: zjiao@umich.edu [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Was, G.S. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States)

    2011-02-15

    Three stainless steel alloys, high-purity 304 (HP304), high-purity 304 with high Si (HP304 + Si) and commercial purity 304 (CP304), were irradiated with 2 MeV protons to a dose of 5 dpa at 360 deg. C and subsequently examined using atom probe tomography (APT) and scanning transmission electron microscopy-energy dispersive X-ray spectrometry (STEM-EDS). Several novel features of radiation-induced segregation and radiation-induced precipitation were observed. There is a significant variation in the composition of enriched and depleted elements in the grain boundary plane and along the dislocation loop core. Boron segregation to the grain boundary prior to irradiation is not affected by the irradiation. Phosphorus segregation is enhanced by irradiation. Carbon depletes at the grain boundary and may be affected by co-segregation with Cr. APT and STEM-EDS measurements are in excellent agreement for almost all the elements studied. The segregation behavior of elements at dislocations mirrors that at the grain boundary, but at a lower magnitude, except for Si. Ni/Si-rich clusters formed in irradiated HP304 + Si and CP304 are probably the precursors of {gamma}' or other Si- and Ni-rich phases. Copper depletion was observed at both the grain boundary and the dislocation loops. Regions adjacent to the depleted zones were sites for Cu cluster formation, which were also spatially correlated with Ni/Si-rich clusters.

  3. Characterization of a Novel Radiation-Induced Sarcoma Cell Line

    Czech Academy of Sciences Publication Activity Database

    Lang, J.; Zhu, W.Z.; Nokes, B.; Sheth, S.G.; Novák, Petr; Fuchs, L.; Watts, G.; Futscher, B. W.; Mineyev, N.; Ring, A.

    2015-01-01

    Roč. 111, č. 6 (2015), s. 669-682 ISSN 0022-4790 Institutional support: RVO:60077344 Keywords : Sarcoma * radiation-induced * breast * cancer Subject RIV: FD - Oncology ; Hematology Impact factor: 3.151, year: 2015

  4. Radiation induced changes in the airway - anaesthetic implications

    African Journals Online (AJOL)

    Adele

    CASE REPORT. Southern African Journal of Anaesthesia & Analgesia - May 2004. 19. Radiation ... Summary: Radiation induces a variety of changes in the airway that can potentially lead to difficult intubation. ... Mask holding and ventilation is.

  5. Image Guidance and Assessment of Radiation Induced Gene Therapy

    National Research Council Canada - National Science Library

    Pelizzari, Charles

    2004-01-01

    Image guidance and assessment techniques are being developed for combined radiation/gene therapy, which utilizes a radiation-inducible gene promoter to cause expression of tumor necrosis factor alpha...

  6. A case of radiation-induced osteosarcoma of the maxilla

    International Nuclear Information System (INIS)

    Tanaka, Rie; Asato, Ryo; Tanaka, Shinzo; Hiratsuka, Yasuyuki; Ito, Juichi

    2003-01-01

    Radiation-induced osteosarcoma in the head and neck region is very rare. A 68-year-old female, who had been treated with radiation for malignant lymphoma of the right maxillary sinus, presented with right cheek swelling. Imaging examinations demonstrated a huge mass occupying the right nasal cavity and paranasal sinuses. Total maxillectomy was performed, and the tumor was histologically diagnosed as osteosarcoma. Diagnosis and treatment for radiation-induced osteosarcoma in the head and neck is discussed. (author)

  7. A case of radiation-induced osteosarcoma of the maxilla

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Rie [Shimada City Hospital, Shizuoka (Japan); Asato, Ryo; Tanaka, Shinzo; Hiratsuka, Yasuyuki; Ito, Juichi [Kyoto Univ. (Japan). Faculty of Medicine

    2003-02-01

    Radiation-induced osteosarcoma in the head and neck region is very rare. A 68-year-old female, who had been treated with radiation for malignant lymphoma of the right maxillary sinus, presented with right cheek swelling. Imaging examinations demonstrated a huge mass occupying the right nasal cavity and paranasal sinuses. Total maxillectomy was performed, and the tumor was histologically diagnosed as osteosarcoma. Diagnosis and treatment for radiation-induced osteosarcoma in the head and neck is discussed. (author)

  8. Radiation-induced neuropathies: collateral damage of improved cancer prognosis

    International Nuclear Information System (INIS)

    Pradat, Pierre-Francois; Maisonobe, Thierry; Psimaras, Dimitri; Lenglet, Timothee; Porcher, Raphael; Lefaix, J.L.; Delenian, S.

    2012-01-01

    Because of the improvement of cancer prognosis, long-term damages of treatments become a medical and public health problem. Among the iatrogenic complications, neurological impairment is crucial to consider since motor disability and pain have a considerable impact on quality of life of long cancer survivors. However, radiation-induced neuropathies have not been the focus of great attention. The objective of this paper is to provide an updated review about the radiation-induced lesions of the peripheral nerve system. Radiation-induced neuropathies are characterized by their heterogeneity in both symptoms and disease course. Signs and symptoms depend on the affected structures of the peripheral nerve system (nerve roots, nerve plexus or nerve trunks). Early-onset complications are often transient and late complications are usually progressive and associated with a poor prognosis. The most frequent and well known is delayed radiation-induced brachial plexopathy, which may follow breast cancer irradiation. Radiation-induced lumbosacral radiculoplexopathy is characterized by pure or predominant lower motor neuron signs. They can be misdiagnosed, confused with amyotrophic lateral sclerosis (ALS) or with leptomeningeal metastases since nodular MRI enhancement of the nerve roots of the cauda equina and increased cerebrospinal fluid protein content can be observed. In the absence of specific markers of the link with radiotherapy, the diagnosis of post-radiation neuropathy may be difficult. Recently, a posteriori conformal radiotherapy with 3D dosimetric reconstitution has been developed to link a precise anatomical site to unexpected excess irradiation. The importance of early diagnosis of radiation-induced neuropathies is underscored by the emergence of new disease-modifying treatments. Although the pathophysiology is not fully understood, it is already possible to target radiation-induced fibrosis but also associated factors such as ischemia, oxidative stress and

  9. Surgical techniques in radiation induced temporal lobe necrosis in nasopharyngeal carcinoma patients.

    Science.gov (United States)

    Alfotih, Gobran Taha Ahmed; Zheng, Mei Guang; Cai, Wang Qing; Xu, Xin Ke; Hu, Zhen; Li, Fang Cheng

    2016-01-01

    Radiation induced brain injury ranges from acute reversible edema to late, irreversible radiation necrosis. Radiation induced temporal lobe necrosis is associated with permanent neurological deficits and occasionally progresses to death. We present our experience with surgery on radiation induced temporal lobe necrosis (RTLN) in nasopharyngeal carcinoma (NPC) patients with special consideration of clinical presentation, surgical technique, and outcomes. This retrospective study includes 12 patients with RTLN treated by the senior author between January 2010 and December 2014. Patients initially sought medical treatment due to headache; other symptoms were hearing loss, visual deterioration, seizure, hemiparesis, vertigo, memory loss and agnosia. A temporal approach through a linear incision was performed for all cases. RTLN was found in one side in 7 patients, and bilaterally in 5. 4 patients underwent resection of necrotic tissue bilaterally and 8 patients on one side. No death occurred in this series of cases. There were no post-operative complications, except 1 patient who developed aseptic meningitis. All 12 patients were free from headache. No seizure occurred in patients with preoperative epilepsy. Other symptoms such as hemiparesis and vertigo improved in all patients. Memory loss, agnosia and hearing loss did not change post-operatively in all cases. The follow-up MR images demonstrated no recurrence of necrotic lesions in all 12 patients. Neurosurgical intervention through a temporal approach with linear incision is warranted in patients with radiation induced temporal lobe necrosis with significant symptoms and signs of increased intracranial pressure, minimum space occupying effect on imaging, or neurological deterioration despite conservative management. Copyright © 2016 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  10. Mitigation of radiation-induced lung fibrosis by angiotensin converting enzyme inhibitors

    International Nuclear Information System (INIS)

    Kma, Lakhan; Gao, Feng; Jacobs, Elizabeth R.; Medhora, Meetha; Fish, Brian L.; Moulder, John E.

    2014-01-01

    The aim of this study was to test the mitigating potential of angiotensin converting enzyme inhibitors (ACEi) against radiation-induced pulmonary fibrosis, which could result from accidental exposure or radiological terrorism. Rats (WAG/RijCmcr) were exposed to a single dose of 13 Gy of X-irradiation to the whole thorax, at the dose rate of 1.43 Gy/min. Three structurally-different ACEi's, captopril (145-207 mg/m 2 /day), enalapril (19-28 mg/m 2 /day) and fosinopril (19-28 mg/m 2 /day) were administered in drinking water beginning 1 week after whole thoracic irradiation. Rats that survived acute pneumonitis (6-12 weeks) were accessed monthly after irradiation for the effects on lung structure and function. Endpoints included breathing rate, wet:dry weight ratio, collagen content and histolopathological studies. Treatment with captopril or enalapril, but not fosinopril, beginning 1 week after 13 Gy X-irradiation improved survival of rats. Mortality of 30-35% was observed with administration of captopril or enalapril compared to 70% for 13 Gy alone. All three ACEi's attenuated radiation-induced lung fibrosis at 7 months after irradiation based on histological indices and measurement of lung collagen. After whole-thoracic irradiation, ACEi's mitigate radiation induced pulmonary fibrosis based on histological and biochemical endpoints. These treatments were effective even when administration was not started until one week after irradiation. Our findings support the therapeutic potential of ACEi's against chronic radiation induced lung injury. (author)

  11. Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

    Science.gov (United States)

    Bednarz, Bryan; Besemer, Abigail

    2017-09-01

    The use of radionuclide therapy in the clinical setting is expected to increase significantly over the next decade. There is an important need to understand the radiation-induced second cancer risk associated with these procedures. In this study the radiation-induced cancer risk in five radionuclide therapy patients was investigated. These patients underwent serial SPECT imaging scans following injection as part of a clinical trial testing the efficacy of a 131Iodine-labeled radiopharmaceutical. Using these datasets the committed absorbed doses to multiple sensitive structures were calculated using RAPID, which is a novel Monte Carlo-based 3D dosimetry platform developed for personalized dosimetry. The excess relative risk (ERR) for radiation-induced cancer in these structures was then derived from these dose estimates following the recommendations set forth in the BEIR VII report. The radiation-induced leukemia ERR was highest among all sites considered reaching a maximum value of approximately 4.5. The radiation-induced cancer risk in the kidneys, liver and spleen ranged between 0.3 and 1.3. The lifetime attributable risks (LARs) were also calculated, which ranged from 30 to 1700 cancers per 100,000 persons and were highest for leukemia and the liver for both males and females followed by radiation-induced spleen and kidney cancer. The risks associated with radionuclide therapy are similar to the risk associated with external beam radiation therapy.

  12. Acute cardiac support with intravenous milrinone promotes recovery from early brain injury in a murine model of severe subarachnoid haemorrhage.

    Science.gov (United States)

    Mutoh, Tomoko; Mutoh, Tatsushi; Nakamura, Kazuhiro; Yamamoto, Yukiko; Tsuru, Yoshiharu; Tsubone, Hirokazu; Ishikawa, Tatsuya; Taki, Yasuyuki

    2017-04-01

    Early brain injury/ischaemia (EBI) is a serious complication early after subarachnoid haemorrhage (SAH) that contributes to development of delayed cerebral ischaemia (DCI). This study aimed to determine the role of inotropic cardiac support using milrinone (MIL) on restoring acute cerebral hypoperfusion attributable to EBI and improving outcomes after experimental SAH. Forty-three male C57BL/6 mice were assigned to either sham surgery (SAH-sham), SAH induced by endovascular perforation plus postconditioning with 2% isoflurane (Control), or SAH plus isoflurane combined with MIL with and without hypoxia-inducible factor inhibitor (HIF-I) pretreatment. Cardiac output (CO) during intravenous MIL infusion (0.25-0.75 μg/kg/min) between 1.5 and 2.5 hours after SAH induction was monitored with Doppler echocardiography. Magnetic resonance imaging (MRI)-continuous arterial spin labelling was used for quantitative cerebral blood flow (CBF) measurements. Neurobehavioral function was assessed daily by neurological score and open field test. DCI was analyzed 3 days later by determining infarction on MRI. Mild reduction of cardiac output (CO) and global cerebral blood flow (CBF) depression were notable early after SAH. MIL increased CO in a dose-dependent manner (P<.001), which was accompanied by improved hypoperfusion, incidence of DCI and functional recovery than Control (P<.05). The neuroprotective effects afforded by MIL or Control were attenuated by hypoxia-inducible factor (HIF) inhibition (P<.05). These results suggest that MIL improves acute hypoperfusion by its inotropic effect, leading to neurobehavioral improvement in mice after severe SAH, in which HIF may be acting as a critical mediator. © 2017 John Wiley & Sons Australia, Ltd.

  13. Synthesis, DNA Cleavage Activity, Cytotoxicity, Acetylcholinesterase Inhibition, and Acute Murine Toxicity of Redox-Active Ruthenium(II) Polypyridyl Complexes.

    Science.gov (United States)

    Alatrash, Nagham; Narh, Eugenia S; Yadav, Abhishek; Kim, Mahn-Jong; Janaratne, Thamara; Gabriel, James; MacDonnell, Frederick M

    2017-07-06

    Four mononuclear [(L-L) 2 Ru(tatpp)] 2+ and two dinuclear [(L-L) 2 Ru(tatpp)Ru(L-L) 2 ] 4+ ruthenium(II) polypyridyl complexes (RPCs) containing the 9,11,20,22-tetraazatetrapyrido[3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]pentacene (tatpp) ligand were synthesized, in which L-L is a chelating diamine ligand such as 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 3,4,7,8-tetramethyl-1,10-phenanthroline (Me 4 phen) or 4,7-diphenyl-1,10-phenanthroline (Ph 2 phen). These Ru-tatpp analogues all undergo reduction reactions with modest reducing agents, such as glutathione (GSH), at pH 7. These, plus several structurally related but non-redox-active RPCs, were screened for DNA cleavage activity, cytotoxicity, acetylcholinesterase (AChE) inhibition, and acute mouse toxicity, and their activities were examined with respect to redox activity and lipophilicity. All of the redox-active RPCs show single-strand DNA cleavage in the presence of GSH, whereas none of the non-redox-active RPCs do. Low-micromolar cytotoxicity (IC 50 ) against malignant H358, CCL228, and MCF7 cultured cell lines was mainly restricted to the redox-active RPCs; however, they were substantially less toxic toward nonmalignant MCF10 cells. The IC 50 values for AChE inhibition in cell-free assays and the acute toxicity of RPCs in mice revealed that whereas most RPCs show potent inhibitory action against AChE (IC 50 values <15 μm), Ru-tatpp complexes as a class are surprisingly well tolerated in animals relative to other RPCs. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Hyperbaric oxygenation was effective in a case of radiation-induced optic neuropathy

    International Nuclear Information System (INIS)

    Saitoh, Ayumi; Dake, Yoshinori; Amemiya, Tsugio

    1995-01-01

    A 68-year-old female underwent radiation treatment followed by surgical extirpation for olfactory neuroblastoma in the left ethmoidal sinus. Acute optic neuropathy developed 16 months later in her left eye. The visual acuity was reduced to finger counting at 30 cm. Treatment with systemic corticosteroid and hyperbaric oxygenation for 2 months resulted in improvement in fundus findings and improvement of visual acuity to 0.5. The findings show the potential effectiveness of hyperbaric oxygen therapy for radiation-induced optic neuropathy. (author)

  15. Hyperbaric oxygenation was effective in a case of radiation-induced optic neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, Ayumi; Dake, Yoshinori; Amemiya, Tsugio [Nagasaki Univ. (Japan). School of Medicine

    1995-03-01

    A 68-year-old female underwent radiation treatment followed by surgical extirpation for olfactory neuroblastoma in the left ethmoidal sinus. Acute optic neuropathy developed 16 months later in her left eye. The visual acuity was reduced to finger counting at 30 cm. Treatment with systemic corticosteroid and hyperbaric oxygenation for 2 months resulted in improvement in fundus findings and improvement of visual acuity to 0.5. The findings show the potential effectiveness of hyperbaric oxygen therapy for radiation-induced optic neuropathy. (author).

  16. Radiation-induced gastrointestinal toxicity. Pathophysiologie, approaches to treatment and prophylaxis

    International Nuclear Information System (INIS)

    Classen, J.; Belka, C.; Paulsen, F.; Budach, W.; Hoffmann, W.; Bamberg, M.

    1998-01-01

    Background: Gastrointestinal toxicity is frequently observed during radiotherapy of malignancies in the abdomen and pelvis. The proposed pathophysiology of radiation enteritis is complex and a variety of different treatment strategies have been suggested for the management of acute radiation-induced diarrhea. Material and methods: Data are presented from an extensive review of the current literature. Results: Radiation-induced diarrhea results from a variety of different pathophysiological mechanisms including malabsorption of bile salts and lactose, imbalances in local bacterial flora and changes in the intestinal patterns of motility. Up to date acute radiation diarrhea is predominantly treated symptomatically using opioide derivates (loperamide) or adsorbants of bile salts such as smectite. Clinical trials have been performed using L. acidophilus, smectite or sucralfate for diarrhea prophylaxis with moderate reduction of acute symptoms. Conclusions: Further evaluation of strategies for diarrhea prophylaxis is warranted. Due to the complex nature of radiation enteritis a multimodal approach taking into account alterations in intestinal motility patterns, malabsorption of bile salts and an imbalance of mucosal bacterial flora may offer new perspectives. (orig.) [de

  17. Characterization of the local immune response to cyst antigens during the acute and elimination phases of primary murine giardiasis.

    Science.gov (United States)

    Abdul-Wahid, Aws; Faubert, Gaétan

    2008-05-01

    During the course of a giardial infection, the host's immune system is presented with a variety of Giardia antigens as trophozoites differentiate, through encysting cells, to form the infective cysts. Previous studies examining the host's immune response during giardial infections have focused on trophozoite-derived antigens (Ags). In this study, we were interested to determine if the host's immune system reacts to cyst Ags during the acute and elimination phases, when there is cyst shedding. For this purpose, we used antigenic extracts from trophozoites (Troph), encysting cells (ENC), and purified giardial cyst walls (PCW), as well as purified recombinant cyst wall protein 2 (rCWP2). Comparative analysis of the parasite extracts using SDS-PAGE analysis and surface-enhanced laser desorption/ionization time of flight mass spectrometry resulted in the detection of 175 protein entities, of which 26 were Troph-specific proteins, 17 ENC-specific proteins, and 31 were PCW-specific proteins. On the other hand, we detected 34 proteins shared between Troph and ENC, 19 proteins that were shared between ENC and PCW, and 29 proteins that were common to Troph and PCW. Finally, we detected 19 proteins that were shared by all three extract samples. BALB/c mice were infected with 10(5)Giardia muris cysts and sacrificed either at the acute or elimination phases of infection (days 12 and 40, respectively), and lymphocytes were isolated from the Peyer's patches (PP). Using flow cytometry, we detected significant increases in the number of PP-derived CD4(+) and CD19(+), but not CD8(+) lymphocytes. Quantification of the number of mucosal IL-4 and IFN-gamma secreting T-lymphocytes by enzyme-linked immunosorbent spot assay showed that these cells reacted by secreting similar levels of IL-4 and IFN-gamma, regardless of the Ag or the phase of infection. Analysis of intestinal humoral immune responses by ELISA resulted in the detection of Ag-specific IgA and IgG intestinal antibodies

  18. Interleukin-1 beta gene deregulation associated with chromosomal rearrangement: A candidate initiating event for murine radiation-myeloid leukemogenesis

    International Nuclear Information System (INIS)

    Silver, A.; Boultwood, J.; Breckon, G.; Masson, W.; Adam, J.; Shaw, A.R.; Cox, R.

    1989-01-01

    The incidence of acute myeloid leukemia (AML) in CBA/H mice following exposure to single acute doses of ionizing radiation has previously been determined. A high proportion of these AMLs are characterized by rearrangement of murine chromosome 2 in the C2 and/or E5-F regions, and there is evidence that these events are a direct consequence of radiation damage to multipotential hemopoietic cells. Using a combination of in situ chromosome hybridization and mRNA analyses, we show that the cytokine gene interleukin-1 beta (IL-1 beta) is encoded in the chromosome 2 F region and is translocated in a chromosome 2---2 rearrangement in an x-ray-induced AML (N36). Also, IL-1 beta is specifically deregulated in N36 and in two other chromosome 2-rearranged AMLs but not in a fourth, which has two cytogenetically normal chromosome 2 copies. We suggest that radiation-induced specific chromosome 2 rearrangement associated with IL-1 beta deregulation may initiate murine leukemogenesis through the uncoupling of normal proliferative control mechanisms in multipotential hemopoietic cells

  19. IL-35 mitigates murine acute graft-versus-host disease with retention of graft-versus-leukemia effects.

    Science.gov (United States)

    Liu, Y; Wu, Y; Wang, Y; Cai, Y; Hu, B; Bao, G; Fang, H; Zhao, L; Ma, S; Cheng, Q; Song, Y; Liu, Y; Zhu, Z; Chang, H; Yu, X; Sun, A; Zhang, Y; Vignali, D A A; Wu, D; Liu, H

    2015-04-01

    IL-35 is a newly discovered inhibitory cytokine secreted by regulatory T cells (Tregs) and may have therapeutic potential in several inflammatory disorders. Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation and caused by donor T cells and inflammatory cytokines. The role of IL-35 in aGVHD is still unknown. Here we demonstrate that IL-35 overexpression suppresses CD4(+) effector T-cell activation, leading to a reduction in alloreactive T-cell responses and aGVHD severity. It also leads to the expansion of CD4(+)Foxp3(+) Tregs in the aGVHD target organs. Furthermore, IL-35 overexpression results in a selective decrease in the frequency of Th1 cells and an increase of IL-10-producing CD4(+) T cells in aGVHD target tissues. Serum levels of TNF-α, IFN-γ, IL-6, IL-22 and IL-23 decrease and IL-10 increases in response to IL-35. Most importantly, IL-35 preserves graft-versus-leukemia effect. Finally, aGVHD grade 2-4 patients have decreased serum IL-35 levels comparing with time-matched patients with aGVHD grade 0-1. Our findings indicate that IL-35 has an important role in reducing aGVHD through promoting the expansion of Tregs and repressing Th1 responses, and should be investigated as the therapeutic strategy for aGVHD.

  20. Inflammatory early events associated to the role of P2X7 receptor in acute murine toxoplasmosis.

    Science.gov (United States)

    Corrêa, Gladys; Almeida Lindenberg, Carolina de; Moreira-Souza, Aline Cristina de Abreu; Savio, Luiz Eduardo Baggio; Takiya, Christina Maeda; Marques-da-Silva, Camila; Vommaro, Rossiane Claudia; Coutinho-Silva, Robson

    2017-04-01

    Activation of the purinergic P2X7 receptor by extracellular ATP (eATP) potentiates proinflammatory responses during infections by intracellular pathogens. Extracellular ATP triggers an antimicrobial response in macrophages infected with Toxoplasma gondii in vitro, suggesting that purinergic signaling may stimulate host defense mechanisms against toxoplasmosis. Here, we provide in vivo evidence in support of this hypothesis, by showing that P2X7 -/- mice are more susceptible than P2X7 +/+ mice to acute infection by the RH strain of T. gondii, and that this phenomenon is associated with a deficient proinflammatory response. Four days post-infection, peritoneal washes from infected P2X7 -/- mice had no or little increase in the levels of the proinflammatory cytokines IL-12, IL-1β, IFN-γ, and TNF-α, whose levels increased markedly in samples from infected P2X7 +/+ mice. Infected P2X7 -/- mice displayed an increase in organ weight and histological alterations in some of the 'shock organs' in toxoplasmosis - the liver, spleen and mesenteric lymph nodes. The liver of infected P2X7 -/- mice had smaller granulomas, but increased parasite load/granuloma. Our results confirm that the P2X7 receptor is involved in containing T. gondii spread in vivo, by stimulating inflammation. Copyright © 2016 Elsevier GmbH. All rights reserved.

  1. Characterization of radiation-induced Apoptosis in rodent cell lines

    International Nuclear Information System (INIS)

    Guo, Min; Chen, Changhu; Ling, C.C.

    1997-01-01

    For REC:myc(ch1), Rat1 and Rat1:myc b cells, we determined the events in the development of radiation-induced apoptosis to be in the following order: cell division followed by chromatin condensation, membrane blebbing, loss of adhesion and the uptake of vital dye. Experimental data which were obtained using 4 He ions of well defined energies and which compared the dependence of apoptosis and clonogenic survival on 4 He range strongly suggested that in our cells both apoptosis and loss of clonogenic survival resulted from radiation damage to the cell nucleus. Corroboratory evidence was that BrdU incorporation sensitized these cells to radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc b cells, we concluded that radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc b cells, we concluded that radiation-induced apoptosis contributed to the overall radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis during late S and G 2 phases reduced the relative radioresistance observed for clonogenic survival during late S and G 2 phases. 30 refs., 8 figs

  2. Trans-generational radiation-induced chromosomal instability in the female enhances the action of chemical mutagens

    International Nuclear Information System (INIS)

    Camats, Nuria; Garcia, Francisca; Parrilla, Juan Jose; Calaf, Joaquim; Martin, Miguel; Caldes, Montserrat Garcia

    2008-01-01

    Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 metaphases from foetal tissues from the foetal offspring of X-irradiated female rats (5 Gy, acute dose) were analysed. The study's results showed that there is radiation-induced genomic instability: the number of aberrant metaphases and the breaks per total metaphases studied increased and were found to be statistically significant (p ≤ 0.05), with regard to the control group. In order to identify how this trans-generational, radiation-induced chromosomal instability could influence the chromosomal behaviour of the offspring of irradiated rat females in front of a chemical agent (aphidicolin), a total of 2481 metaphases were studied. The observed results showed that there is an enhancement of the action of the chemical agent: chromosomal breaks per aberrant metaphases show significant differences (p ≤ 0.05) in the X-ray- and aphidicolin-treated group as regards the aphidicolin-treated group. In conclusion, our findings indicate that there is trans-generational, radiation-induced chromosomal instability in the foetal cells

  3. Trans-generational radiation-induced chromosomal instability in the female enhances the action of chemical mutagens

    Energy Technology Data Exchange (ETDEWEB)

    Camats, Nuria [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Garcia, Francisca [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Parrilla, Juan Jose [Servicio de Ginecologia y Obstetricia, Hospital Universitario Virgen de la Arrixaca, 30120 El Palmar, Murcia (Spain); Calaf, Joaquim [Servei de Ginecologia i Obstetricia, Hospital Universitari de la Santa Creu i Sant Pau, 08025 Barcelona (Spain); Martin, Miguel [Departament de Pediatria, d' Obstetricia i Ginecologia i de Medicina Preventiva, Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Caldes, Montserrat Garcia [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Barcelona (Spain)], E-mail: Montserrat.Garcia.Caldes@uab.es

    2008-04-02

    Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 metaphases from foetal tissues from the foetal offspring of X-irradiated female rats (5 Gy, acute dose) were analysed. The study's results showed that there is radiation-induced genomic instability: the number of aberrant metaphases and the breaks per total metaphases studied increased and were found to be statistically significant (p {<=} 0.05), with regard to the control group. In order to identify how this trans-generational, radiation-induced chromosomal instability could influence the chromosomal behaviour of the offspring of irradiated rat females in front of a chemical agent (aphidicolin), a total of 2481 metaphases were studied. The observed results showed that there is an enhancement of the action of the chemical agent: chromosomal breaks per aberrant metaphases show significant differences (p {<=} 0.05) in the X-ray- and aphidicolin-treated group as regards the aphidicolin-treated group. In conclusion, our findings indicate that there is trans-generational, radiation-induced chromosomal instability in the foetal

  4. Physiological noise in murine solid tumours using T2*-weighted gradient-echo imaging: a marker of tumour acute hypoxia?

    International Nuclear Information System (INIS)

    Baudelet, Christine; Ansiaux, Reginald; Jordan, Benedicte F; Havaux, Xavier; Macq, Benoit; Gallez, Bernard

    2004-01-01

    with no contrast enhancement as the result of vessel functional impairment. Furthermore, transient fluctuations appeared to occur preferentially in neoangiogenic hyperpermeable vessels. The present study suggests that spontaneous T2*-weighted GRE fluctuations are very likely to be related to the spontaneous fluctuations in blood flow and oxygenation associated with the pathophysiology of acute hypoxia in tumours. The disadvantage of the T2*-weighted GRE MRI technique is the complexity of signal interpretation with regard to pO 2 changes. Compared to established techniques such as intravital microscopy or histological assessments, the major advantage of the MRI technique lies in its capacity to provide simultaneously both temporal and detailed spatial information on spontaneous fluctuations throughout the tumour

  5. Radiation-induced bystander effects: Are they good bad or both?; Les nouvelles orientations en radiobiologie et radiopathologie

    Energy Technology Data Exchange (ETDEWEB)

    Le Guen, B.; Lallemand, J. [Electricite de France (EDF), 75 - Paris (France); Averbeck, D. [Institut Curie, 75 - Paris (France); Chetioui, A. [Paris-6 Univ., 75 (France); Gardes-Albert, M. [Paris-5 Univ., 75 (France); Mothersill, C. [Mc Master Univ., Hamilton (Canada); Gourmelon, P.; Benderitter, M. [Institut de Radioprotection et de Surete Nucleaire, 92 - Clamart (France); Chevillard, S.; Martin, M. [CEA Fontenay-aux-Roses, Dir. des sciences du vivant, 92 (France); Verrelle, P. [Centre Jean-Perrin, 63 - Clermont-Ferrand (France)

    2004-07-01

    The different contributions are as follow: the current events on the cellular responses to irradiation ( part one and two); From physico-chemistry to radiobiology: new knowledge (part one and two); Radiation-induced bystander effects: are they good bad or both; recognition of the multi visceral failure in the acute irradiation syndrome; integrated approach of the tissue carcinogenesis: differential effect sane tissue-tumoral tissue; differential diagnosis of thyroid cancers by the transcriptoma analysis. (N.C.)

  6. Role of endothelium in radiation-induced normal tissue damages

    International Nuclear Information System (INIS)

    Milliat, F.

    2007-05-01

    More than half of cancers are treated with radiation therapy alone or in combination with surgery and/or chemotherapy. The goal of radiation therapy is to deliver enough ionising radiation to destroy cancer cells without exceeding the level that the surrounding healthy cells can tolerate. Unfortunately, radiation-induced normal tissue injury is still a dose limiting factor in the treatment of cancer with radiotherapy. The knowledge of normal tissue radiobiology is needed to determine molecular mechanisms involved in normal tissue pathogenic pathways in order to identify therapeutic targets and develop strategies to prevent and /or reduce side effects of radiation therapy. The endothelium is known to play a critical role in radiation-induced injury. Our work shows that endothelial cells promote vascular smooth muscle cell proliferation, migration and fibro-genic phenotype after irradiation. Moreover, we demonstrate for the first time the importance of PAI-1 in radiation-induced normal tissue damage suggesting that PAI-1 may represent a molecular target to limit injury following radiotherapy. We describe a new role for the TGF-b/Smad pathway in the pathogenesis of radiation-induced damages. TGF-b/Smad pathway is involved in the fibro-genic phenotype of VSMC induced by irradiated EC as well as in the radiation-induced PAI-1 expression in endothelial cells. (author)

  7. Radiation-induced camptocormia and dropped head syndrome. Review and case report of radiation-induced movement disorders

    International Nuclear Information System (INIS)

    Seidel, Clemens; Kuhnt, Thomas; Kortmann, Rolf-Dieter; Hering, Kathrin

    2015-01-01

    In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.) [de

  8. Involvement of ERK-Nrf-2 signaling in ionizing radiation induced cell death in normal and tumor cells.

    Directory of Open Access Journals (Sweden)

    Raghavendra S Patwardhan

    Full Text Available Prolonged oxidative stress favors tumorigenic environment and inflammation. Oxidative stress may trigger redox adaptation mechanism(s in tumor cells but not normal cells. This may increase levels of intracellular antioxidants and establish a new redox homeostasis. Nrf-2, a master regulator of battery of antioxidant genes is constitutively activated in many tumor cells. Here we show that, murine T cell lymphoma EL-4 cells show constitutive and inducible radioresistance via activation of Nrf-2/ERK pathway. EL-4 cells contained lower levels of ROS than their normal counterpart murine splenic lymphocytes. In response to radiation, the thiol redox circuits, GSH and thioredoxin were modified in EL-4 cells. Pharmacological inhibitors of ERK and Nrf-2 significantly enhanced radiosensitivity and reduced clonogenic potential of EL-4 cells. Unirradiated lymphoma cells showed nuclear accumulation of Nrf-2, upregulation of its dependent genes and protein levels. Interestingly, MEK inhibitor abrogated its nuclear translocation suggesting role of ERK in basal and radiation induced Nrf-2 activation in tumor cells. Double knockdown of ERK and Nrf-2 resulted in higher sensitivity to radiation induced cell death as compared to individual knockdown cells. Importantly, NF-kB which is reported to be constitutively active in many tumors was not present at basal levels in EL-4 cells and its inhibition did not influence radiosensitivity of EL-4 cells. Thus our results reveal that, tumor cells which are subjected to heightened oxidative stress employ master regulator cellular redox homeostasis Nrf-2 for prevention of radiation induced cell death. Our study reveals the molecular basis of tumor radioresistance and highlights role of Nrf-2 and ERK.

  9. Prophylactic role of melatonin against radiation induced damage in mouse cerebellum with special reference to Purkinje cells

    Energy Technology Data Exchange (ETDEWEB)

    Sisodia, Rashmi; Kumari, Seema; Verma, Rajesh Kumar; Bhatia, A L [Neurobiology Laboratory, Department of Zoology, University of Rajasthan, Jaipur 302004 (India)

    2006-06-15

    Melatonin, a hormone with a proven antioxidative efficacy, crosses all morphophysiological barriers, including the blood-brain barrier, and distributes throughout the cell. The present study is an attempt to investigate the prophylactic influence of a chronic low level of melatonin against an acute radiation induced oxidative stress in the cerebellum of Swiss albino mice, with special reference to Purkinje cells. After 15 days of treatment the mice were sacrificed at various intervals from 1 to 30 days. Biochemical parameters included lipid peroxidation (LPO) and glutathione (GSH) levels as the endpoints. The quantitative study included alterations in number and volume of Purkinje cells. Swiss albino mice were orally administered a very low dose of melatonin (0.25 mg/mouse/day) for 15 consecutive days before single exposure to 4 Gy gamma radiation. Melatonin checked the augmented levels of LPO, by approximately 55%, by day 30 day post-exposure. Radiation induced depleted levels of GSH could be raised by 68.9% by day 30 post-exposure. Radiation exposure resulted in a reduction of the volume of Purkinje cells and their total number. The administration of melatonin significantly protected against the radiation induced decreases in Purkinje cell volume and number. Results indicate the antioxidative properties of melatonin resulting in its prophylactic property against radiation induced biochemical and cellular alterations in the cerebellum. The findings support the idea that melatonin may be used as an anti-irradiation drug due to its potent free radical scavenging and antioxidative efficacy.

  10. Effect of dose on radiation-induced conductivity in polymers

    International Nuclear Information System (INIS)

    Tyutnev, A.P.; Saenko, V.S.; Pozhidaev, E.D.; Ikhsanov, R.Sh.

    2007-01-01

    Numerical simulation of radiation-induced conductivity in polymers upon long-term irradiation on the basis of the generalized Rose-Fowler-Vaisberg model, which allows for both dipolar carrier transport and generation of radiation traps during irradiation, was performed. The unusual properties of radiation-induced conductivity, such as the appearance of a maximum on current transients, the absence of a steady state, and a substantial difference between these curves for the first and subsequent irradiation, are rationalized in terms of the formation of free radicals, the major feature of radiolysis in the chemical aspect. This interpretation does not require the involvement of degradation or crosslinking processes, unlike other interpretations that appear in the literature. With the use of low-density polyethylene as an example, it was shown that radiation-induced conductivity both upon pulse and continuous irradiation can satisfactorily be described with the unified set of parameters of the generalized Rose-Fowler-Vaisberg model [ru

  11. Membrane phospholipids and radiation-induced death of mammalian cells

    International Nuclear Information System (INIS)

    Wolters, H.

    1987-01-01

    Radiation-induced cell killing is generally believed to be a consequence of residual DNA damage or damage that is mis-repaired. However, besides this DNA damage, damage to other molecules or structures of the cell may be involved in the killing. Especially membranes have been suggested as a determinant in cellular radiosensitivity. In this thesis experiments are described, dealing with the possible involvement of membranes in radiation-induced killing of mammalian cells. A general treatise of membrane structure is followed by information concerning deleterious effects of radiation on membranes. Consequences of damage to structure and function of membranes are reviewed. Thereafter evidence relating to the possible involvement of membranes in radiation-induced cell killing is presented. (Auth.)

  12. Mechanistic issues for modeling radiation-induced segregation

    International Nuclear Information System (INIS)

    Simonen, E.P.; Bruemmer, S.M.

    1993-03-01

    Model calculations of radiation-induced chromium depletion and radiation-induced nickel enrichment at grain boundaries are compared to measured depletions and enrichments. The model is calibrated to fit chromium depletion in commercial purity 304 stainless steel irradiated in boiling water reactor (BWR) environments. Predicted chromium depletion profiles and the dose dependence of chromium concentration at grain boundaries are in accord with measured trends. Evaluation of chromium and nickel profiles in three neutron, and two ion, irradiation environments reveal significant inconsistencies between measurements and predictions

  13. Radiation-induced radical ions in calcium sulfite

    Science.gov (United States)

    Bogushevich, S. E.

    2006-07-01

    We have used EPR to study the effect of γ radiation on calcium sulfite. We have observed and identified the radiation-induced radical ions SO 2 - (iso) with g = 2.0055 and SO 2 - (orth-1) with g1 = 2.0093, g2 = 2.0051, g3 = 2.0020, identical to the initial and thermally induced SO 2 - respectively, SO 3 - (iso) with g = 2.0031 and SO 3 - (axial) with g⊥ = 2.0040, g∥ = 2.0023, identical to mechanically induced SO 3 - . We have established the participation of radiation-induced radical ions SO 3 - in formation of post-radiation SO 2 - .

  14. Radiation induced ionic polymerisation and grafting of vinyl monomers

    International Nuclear Information System (INIS)

    Stannett, V.T.

    1981-01-01

    Some special aspects of the radiation induced ionic polymerisation and grafting of vinyl monomers will be described. In particular the effects of solvents on the cationic polymerisation of the vinyl ethers will be discussed in detail. The unequivocal free ion nature of the polymerisation makes such information of considerable general interest. Estimates of the propagation rate constants with free cation polymerisation in solvents of different dielectric constants and solvation powers will be presented. Finally, some observations on the radiation induced graft polymerisation of ethyl vinyl ether to poly(vinyl chloride) and to polypropylene will be presented. (author)

  15. Radiation-induced osteosarcoma of the calvaria; Case report

    Energy Technology Data Exchange (ETDEWEB)

    Sugita, Yasuo; Shigemori, Minoru; Miyagi, Jun; Ochiai, Satoshi; Lee, Souichi; Watanabe, Toshinori; Abe, Hitoshi; Morimatsu, Minoru [Kurume Univ., Fukuoka (Japan). School of Medicine

    1992-01-01

    The authors report a case of radiation-induced calvarial osteosarcoma. A 58-year-old female received subtotal removal of the pituitary adenoma and 5000 rads postoperative irradiation. Seven years later, an osteoblastic osteosarcoma occurred in the frontotemporal region. She received total tumor removal and chemotherapy. However, computed tomography subsequently revealed multiple small lesions at the margin of the bone flap. A chest x-ray film demonstrated lung metastasis. Local recurrence and lung metastasis require careful attention in radiation-induced osteosarcoma patients. (author).

  16. Radiation induced mitotic delay and stimulation of growth

    International Nuclear Information System (INIS)

    Feldmann, A.

    1974-01-01

    The mechanisms responsible for the radiation induced mitotic delay and stimulation of growth are discussed in connection with the results of studies in Lemna minor and Lepidium sativum. The action of temperature seems to be of major importance. As many authors suggest that various chemical agents and slight intoxications also affect mitosis in a way similar to that induced by ionizing radiation, the radiation induced stimulation has lost its specific character and approaches might be found for further investigations of this phenomenon. (MG) [de

  17. Radiation-induced void swelling in metals and alloys

    International Nuclear Information System (INIS)

    Zelinskij, V.F.; Neklyudov, I.M.; Ozhigov, L.S.; Reznichenko, Eh.A.; Rozhkov, V.V.; Chernyaeva, T.T.

    1979-01-01

    Main regularities in the development of radiation-induced void swelling are considered. Special attention is paid to consideration of a possibility to obtain information on material behaviour under conditions of reactor irradiation proceeding from the data of simulation experiments and to methods of rate control, for the processes which occur in material during irradiation and further annealing by the way of rationalized alloying, of thermomechanical treatment and programmed change of irradiation conditions under operation. Problems of initiation and growth of voids in irradiated materials are discussed as well as the ways to decrease the rate of radiation-induced void swelling

  18. Lovastatin attenuates ionizing radiation-induced normal tissue damage in vivo

    International Nuclear Information System (INIS)

    Ostrau, Christian; Huelsenbeck, Johannes; Herzog, Melanie; Schad, Arno; Torzewski, Michael; Lackner, Karl J.; Fritz, Gerhard

    2009-01-01

    Background and purpose: HMG-CoA-reductase inhibitors (statins) are widely used lipid-lowering drugs. Moreover, they have pleiotropic effects on cellular stress responses, proliferation and apoptosis in vitro. Here, we investigated whether lovastatin attenuates acute and subchronic ionizing radiation-induced normal tissue toxicity in vivo. Materials and methods: Four hours to 24 h after total body irradiation (6 Gy) of Balb/c mice, acute pro-inflammatory and pro-fibrotic responses were analyzed. To comprise subchronic radiation toxicity, mice were irradiated twice with 2.5 Gy and analyses were performed 3 weeks after the first radiation treatment. Molecular markers of inflammation and fibrosis as well as organ toxicities were measured. Results: Lovastatin attenuated IR-induced activation of NF-κB, mRNA expression of cell adhesion molecules and mRNA expression of pro-inflammatory and pro-fibrotic marker genes (i.e. TNFα, IL-6, TGFβ, CTGF, and type I and type III collagen) in a tissue- and time-dependent manner. γH2AX phosphorylation stimulated by IR was not affected by lovastatin, indicating that the statin has no major impact on the induction of DNA damage in vivo. Radiation-induced thrombopenia was significantly alleviated by lovastatin. Conclusions: Lovastatin inhibits both acute and subchronic IR-induced pro-inflammatory and pro-fibrotic responses and cell death in normal tissue in vivo. Therefore, lovastatin might be useful for selectively attenuating acute and subchronic normal tissue damage caused by radiotherapy.

  19. Radiation induced mutations in Phaseolus vulgaris L

    International Nuclear Information System (INIS)

    Al-Rubeai, M.A.F.

    1982-01-01

    A selection of various macro- and micro-mutations was undertaken in the M2 generation of Phaseolus vulgaris cultivars after seed exposure to acute gamma radiation doses of 2.5, 5, 7, 10 and 15 Kr. The chlorophyll mutation was positively correlated with dose. Nevertheless, the highest frequency was at 7 Kr. Several interesting morphological mutants were observed. There were dwarf, stiff stem, shiny small leaf, narrow leaf and green giant mutants. Two selected micromutants were superior in seed yield capacity to their parents. The high yields were related to the high number of pods per plant. In 'The Prince' (seed color: red with beige marbling) several mutants with seeds of black color marbled with beige were selected. These seeds gave M3 segregants exhibiting a range of seed colors including white. Many of these M3 plants were short, early flowering and highly sterile. The work demonstrated that the pigmentation character can readily be changed, and confirmed that the variability induced by radiation can be exploited to obtain desirable mutations. (Author) [pt

  20. Radiation-induced nitric oxide mitigates tumor hypoxia and radioresistance in a murine SCCVII tumor model

    International Nuclear Information System (INIS)

    Nagane, Masaki; Yasui, Hironobu; Yamamori, Tohru; Zhao, Songji; Kuge, Yuji; Tamaki, Nagara; Kameya, Hiromi; Nakamura, Hideo; Fujii, Hirotada; Inanami, Osamu

    2013-01-01

    Highlights: •IR-induced NO increased tissue perfusion and pO 2 . •IR increased NO production in tumors without changes in the mRNA and protein levels of NOS isoforms. •NOS activity assay showed that IR upregulated eNOS activity in tumors. •IR-induced NO decreased tumor hypoxia and altered tumor radiosensitivity. -- Abstract: Tumor hypoxia, which occurs mainly as a result of inadequate tissue perfusion in solid tumors, is a well-known challenge for successful radiotherapy. Recent evidence suggests that ionizing radiation (IR) upregulates nitric oxide (NO) production and that IR-induced NO has the potential to increase intratumoral circulation. However, the kinetics of NO production and the responsible isoforms for NO synthase in tumors exposed to IR remain unclear. In this study, we aimed to elucidate the mechanism by which IR stimulates NO production in tumors and the effect of IR-induced NO on tumor radiosensitivity. Hoechst33342 perfusion assay and electron spin resonance oxymetry showed that IR increased tissue perfusion and pO 2 in tumor tissue. Immunohistochemical analysis using two different hypoxic probes showed that IR decreased hypoxic regions in tumors; treatment with a nitric oxide synthase (NOS) inhibitor, L-NAME, abrogated the effects of IR. Moreover, IR increased endothelial NOS (eNOS) activity without affecting its mRNA or protein expression levels in SCCVII-transplanted tumors. Tumor growth delay assay showed that L-NAME decreased the anti-tumor effect of fractionated radiation (10 Gy × 2). These results suggested that IR increased eNOS activity and subsequent tissue perfusion in tumors. Increases in intratumoral circulation simultaneously decreased tumor hypoxia. As a result, IR-induced NO increased tumor radiosensitivity. Our study provides a new insight into the NO-dependent mechanism for efficient fractionated radiotherapy

  1. Poor outcome in radiation-induced constrictive pericarditis

    International Nuclear Information System (INIS)

    Karram, T.; Rinkevitch, D.; Markiewicz, W.

    1993-01-01

    The purpose was to compare the outcome of patients with radiation-induced constrictive pericarditis versus patients with constiction due to another etiology. Twenty patients with constrictive pericarditis were seen during 1975-1986 at a single medical center. Six had radiation-induced constrictive pericarditis (Group A). The etiology was idiopathic in ten subjects and secondary to carcinomatous encasement, chronic renal failure, purulent infection and tuberculosis in one patient each (Group B, N = 14). Meang age was 53.4 ± 15.5 years. Extensive pericardiectomy was performed in 3/6 Group A and 13/14 Group B patients. All Group A patients died, 4 weeks - 11 years post-diagnosis (median = 10 months). Two Group A patients died suddenly, one died post-operatively of respiratory failure, another of pneumonia and two of recurrent carcinoma. Thirteen Group B patients are alive (median follow-up = 72 months). The only death in this group was due to metastatic cancer. The poor outcome with radiation-induced constriction is probably multi-factorial. Poor surgical outcome is to be expected in patients with evidence of recurrent tumor, high-dose irradiation, pulmonary fibrosis or associated radiation-induced myocardinal, valvular or coronary damage

  2. Homoeologous chromatin exchange in a radiation-induced gene transfer

    International Nuclear Information System (INIS)

    Dvorak, J.; Knott, D.R.

    1977-01-01

    Some of the ionizing-radiation-induced translocations between alien and wheat chromosomes show no deleterious effects and are transmitted normally through the pollen. Translocations of this type will be called ''compensating''. In one such compensating translocation, designated T4, it was found that chromatin in the long arm of wheat chromosome 7D was replaced with homoeologous chromatin of the Agropyron chromosome

  3. Radiation-induced vascular lesions of the skin: an overview

    NARCIS (Netherlands)

    Flucke, U.E.; Requena, L.; Mentzel, T.

    2013-01-01

    Radiation-induced cutaneous vascular neoplasms occur infrequently and comprise benign, so-called atypical vascular lesions (AVL) and angiosarcomas (AS), often being high-grade malignant tumors. Both arise most frequently within previously irradiated skin in breast-conserving-treated mammary cancer

  4. Radiation-induced nitration of organic compounds in aqueous solutions

    International Nuclear Information System (INIS)

    Ershov, B.G.; Gordeev, A.V.; Bykov, G.L.

    2009-01-01

    Radiation-induced nitration of organic compounds in aqueous solutions was studied. It was found that γ-irradiation of solutions containing acetic and nitric acid and/or their salts gives nitromethane. Dependences of the product yield on the absorbed dose and the contents of components were established. The mechanism of radiation nitration involving radicals is discussed. (author)

  5. Seven cases of radiation-induced cutaneous squamous cell carcinoma

    International Nuclear Information System (INIS)

    Sugita, Kazunari; Yamamoto, Osamu; Suenaga, Yoshinori

    2000-01-01

    We report 7 cases of radiation-induced skin cancer. The diagnosis was based on the history of radiotherapy for benign skin diseases (5 cases) and of occupational exposures to medical doctors (2 cases). All cases were squamous cell carcinomas which arose from chronic radiodermatitis. The estimated latent period of these tumors ranged from 6 to 64 years, with an average of 29.9 years. After surgical treatments of the lesions, no local recurrences were observed in all cases. Benign skin diseases had sometimes been treated with low-energy radiation before the 1960s. Considering the estimated latent period, the peak time point of developing risk of radiation-induced skin cancer by such treatment has been already passed, however, the danger of it should not be ignored in future. In association with multiplicity of radiation usage, occupational exposure of radiation may develop the risk of occurrence of skin cancer in future. Therefore, we should recognize that radiation-induced skin cancer is not in the past. In the cases of chronic skin diseases showing warty keratotic growth, erosion and ulcer, we should include chronic radio-dermatitis in the differential diagnosis. It is necessary to recall all patients about the history of radiotherapy or radiation exposure. Rapid histopathological examination is mandatory because of the suspicion of radiation-induced skin cancer. (author)

  6. Radiation-induced hondrosarcoma - a clinical case from our practice

    International Nuclear Information System (INIS)

    Marinova, L.; Georgiev, R.; Mihaylova, I.

    2013-01-01

    We present a clinical case of radiation - induced occipital extracerebral chondrosarcoma in 36 years old young man. The patient had undergone two brain operations 8 years ago due to oligodendroglioma in the left temporo - parietal area. These surgical interventions were partial and subtotal tumor extirpation, followed by local radiotherapy to the brain to a total dose of 56Gy. The necessity of immunohistochemistry (IHH) analysis for pathologic differential diagnosis in high grade brain and peripheral tumors was discussed. In this particular case a precise differential diagnosis between peripheral chondrosarcoma and Ewing sarcoma/pPNET is needed. important risk factors for the development of radiation-induced brain tumors and chondrosarcoma, extremely rarely diagnosed, was discussed. A very accurate precising of the treatment radiation dose is needed in young patients with malignant brain tumors, not only in the surrounding healthy brain tissues, but also in other tissues, such as skin, subcutaneous layer and bone. The exceeding of the radiation dose in the bone above 45-50 Gy, increases the risk of radiation - induced sarcoma with latent period over 8 years. Key words: Hondrosarcoma. Radiotherapy. Radiation-induced Sarcoma. Complex Treatment. Immunohistochemistry

  7. Dose rate effectiveness in radiation-induced teratogenesis in mice

    International Nuclear Information System (INIS)

    Kato, F.; Ootsuyama, A.; Norimura, T.

    2000-01-01

    To investigate the role of p53 gene in tissue repair of teratogenic injury, we compared incidence of radiation-induced malformations in homozygous p53(-/-) mice, heterozygous p53(+/-) mice and wild-type p53(+/+) mice. After X-irradiation with 2 Gy at high dose rate on 9.5 days of gestation, p53(-/-) mice showed higher incidences of anomalies and higher resistance to prenatal deaths than p53(+/+) mice. This reciprocal relationship of radiosensitivity to anomalies and deaths supports the notion that embryos or fetuses have a p53-dependent 'guardian' that aborts cells bearing radiation-induced teratogenic DNA damage. In fact, after X-irradiation, the number of apoptotic cells was greatly increased in p53(+/+) fetuses but not in p53(-/-) fetuses. The same dose of γ-ray exposure at low dose rate on 9.5-10.5 day of gestation produced significant reduction of radiation-induced malformation in p53(+/+) and p53(+/-) mice, remained teratogenic for p53(-/-) mice. These results suggest that complete elimination of teratogenic damage from irradiated tissues requires the concerted cooperation of two mechanisms; proficient DNA repair and the p53-dependent apoptotic tissue repair. When concerted DNA repair and apoptosis functions efficiently, there is a threshold dose-rate for radiation-induced malformations. (author)

  8. Kinetics of radiation-induced segregation in ternary alloys

    International Nuclear Information System (INIS)

    Lam, N.O.; Kumar, A.; Wiedersich, H.

    1982-01-01

    Model calculations of radiation-induced segregation in ternary alloys have been performed, using a simple theory. The theoretical model describes the coupling between the fluxes of radiation-induced defects and alloying elements in an alloy A-B-C by partitioning the defect fluxes into those occurring via A-, B-, and C-atoms, and the atom fluxes into those taking place via vacancies and interstitials. The defect and atom fluxes can be expressed in terms of concentrations and concentration gradients of all the species present. With reasonable simplifications, the radiation-induced segregation problem can be cast into a system of four coupled partial-differential equations, which can be solved numerically for appropriate initial and boundary conditions. Model calculations have been performed for ternary solid solutions intended to be representative of Fe-Cr-Ni and Ni-Al-Si alloys under various irradiation conditions. The dependence of segregation on both the alloy properties and the irradiation variables, e.g., temperature and displacement rate, was calculated. The sample calculations are in good qualitative agreement with the general trends of radiation-induced segregation observed experimentally

  9. Seven cases of radiation-induced cutaneous squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sugita, Kazunari; Yamamoto, Osamu; Suenaga, Yoshinori [Univ. of Occupational and Environmental Health, Kitakyushu, Fukuoka (Japan). School of Medicine

    2000-09-01

    We report 7 cases of radiation-induced skin cancer. The diagnosis was based on the history of radiotherapy for benign skin diseases (5 cases) and of occupational exposures to medical doctors (2 cases). All cases were squamous cell carcinomas which arose from chronic radiodermatitis. The estimated latent period of these tumors ranged from 6 to 64 years, with an average of 29.9 years. After surgical treatments of the lesions, no local recurrences were observed in all cases. Benign skin diseases had sometimes been treated with low-energy radiation before the 1960s. Considering the estimated latent period, the peak time point of developing risk of radiation-induced skin cancer by such treatment has been already passed, however, the danger of it should not be ignored in future. In association with multiplicity of radiation usage, occupational exposure of radiation may develop the risk of occurrence of skin cancer in future. Therefore, we should recognize that radiation-induced skin cancer is not in the past. In the cases of chronic skin diseases showing warty keratotic growth, erosion and ulcer, we should include chronic radio-dermatitis in the differential diagnosis. It is necessary to recall all patients about the history of radiotherapy or radiation exposure. Rapid histopathological examination is mandatory because of the suspicion of radiation-induced skin cancer. (author)

  10. Poor outcome in radiation-induced constrictive pericarditis

    Energy Technology Data Exchange (ETDEWEB)

    Karram, T.; Rinkevitch, D.; Markiewicz, W. (Technion Medical School, Haifa (Israel))

    1993-01-15

    The purpose was to compare the outcome of patients with radiation-induced constrictive pericarditis versus patients with constiction due to another etiology. Twenty patients with constrictive pericarditis were seen during 1975-1986 at a single medical center. Six had radiation-induced constrictive pericarditis (Group A). The etiology was idiopathic in ten subjects and secondary to carcinomatous encasement, chronic renal failure, purulent infection and tuberculosis in one patient each (Group B, N = 14). Meang age was 53.4 [+-] 15.5 years. Extensive pericardiectomy was performed in 3/6 Group A and 13/14 Group B patients. All Group A patients died, 4 weeks - 11 years post-diagnosis (median = 10 months). Two Group A patients died suddenly, one died post-operatively of respiratory failure, another of pneumonia and two of recurrent carcinoma. Thirteen Group B patients are alive (median follow-up = 72 months). The only death in this group was due to metastatic cancer. The poor outcome with radiation-induced constriction is probably multi-factorial. Poor surgical outcome is to be expected in patients with evidence of recurrent tumor, high-dose irradiation, pulmonary fibrosis or associated radiation-induced myocardinal, valvular or coronary damage.

  11. Homoeologous chromatin exchange in a radiation-induced gene transfer

    Energy Technology Data Exchange (ETDEWEB)

    Dvorak, J; Knott, D R [Department of Crop Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

    1977-03-01

    Some of the ionizing-radiation-induced translocations between alien and wheat chromosomes show no deleterious effects and are transmitted normally through the pollen. Translocations of this type will be called ''compensating''. In one such compensating translocation, designated T4, it was found that chromatin in the long arm of wheat chromosome 7D was replaced with homologous chromatin of the Agropyron chromosome.

  12. Radiation-induced augmentation of the immune response

    International Nuclear Information System (INIS)

    Anderson, R.E.; Lefkovits, I.; Troup, G.M.

    1980-01-01

    Radiation-induced augmentation of the immune response has been shown to occur both in vivo and in vitro. Evidence is presented to implicate injury to an extremely radiosensitive T cell in the expression of this phenomenon. Experiments are outlined which could be employed to support or reflect this hypothesis

  13. Preparation of polymer microspheres by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Naka, Y.; Yamamoto, Y.; Yoshida, Y.; Tagawa, S.

    1995-01-01

    Cross-liking monomer, diethylene glycol dimethacrylate gives microspheres from organic solution by radiation-induced polymerization. /One of the remarkable result is that the number of the microspheres is not changing during the polymerization. Ethyl methacrylate, maleic anhydride, styrene and acrylamide are used as comonomers. These comonomers give the microspheres in the range of 0 to 0.4 as mol fractions. (author)

  14. Nicaraven attenuates radiation-induced injury in hematopoietic stem/progenitor cells in mice.

    Directory of Open Access Journals (Sweden)

    Miho Kawakatsu

    Full Text Available Nicaraven, a chemically synthesized hydroxyl radical-specific scavenger, has been demonstrated to protect against ischemia-reperfusion injury in various organs. We investigated whether nicaraven can attenuate radiation-induced injury in hematopoietic stem/progenitor cells, which is the conmen complication of radiotherapy and one of the major causes of death in sub-acute phase after accidental exposure to high dose radiation. C57BL/6 mice were exposed to 1 Gy γ-ray radiation daily for 5 days in succession (a total of 5 Gy, and given nicaraven or a placebo after each exposure. The mice were sacrificed 2 days after the last radiation treatment, and the protective effects and relevant mechanisms of nicaraven in hematopoietic stem/progenitor cells with radiation-induced damage were investigated by ex vivo examination. We found that post-radiation administration of nicaraven significantly increased the number, improved the colony-forming capacity, and decreased the DNA damage of hematopoietic stem/progenitor cells. The urinary levels of 8-oxo-2'-deoxyguanosine, a marker of DNA oxidation, were significantly lower in mice that were given nicaraven compared with those that received a placebo treatment, although the levels of intracellular and mitochondrial reactive oxygen species in the bone marrow cells did not differ significantly between the two groups. Interestingly, compared with the placebo treatment, the administration of nicaraven significantly decreased the levels of the inflammatory cytokines IL-6 and TNF-α in the plasma of mice. Our data suggest that nicaraven effectively diminished the effects of radiation-induced injury in hematopoietic stem/progenitor cells, which is likely associated with the anti-oxidative and anti-inflammatory properties of this compound.

  15. Specitic gene alterations in radiation-induced tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Joo Mee; Kang, Chang Mo; Lee, Seung Sook; Cho, Chul Koo; Bae, Sang Woo; Lee, Su Jae; Lee, Yun Sil [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2004-07-01

    To identify a set of genes involved in the development of radiation-induced tumorigenesis, we used DNA microarrays consisting of 1,176 mouse genes and compared expression profiles of radioresistant cells, designated NIH3T3-R1 and -R4. These cells were tumorigenic in a nude mouse grafting system, as compared to the parental NIH3T3 cells. Expressions of MDM2, CDK6 and CDC25B were found to increase more than 3-fold. Entactin protein levels were downregulated in NIH3T3-R1 and -R4 cells. Changes in expression genes were confirmed by reverse transcription-PCR or western blotting. When these genes were transfected to NIH3T3 cells, the CDC25B and MDM2 overexpressing NIH3T3 cells showed radioresistance, while 2 CDK6 overexpressing cells did not. In the case of entactin overexpressing NIH3T3-R1 or R-4 cells were still radioresistant. Furthermore, the CDC25B and MDM2 overexpressing cells grafted to nude mice, were tumorigenic. NIH3T3-R1 and R4 cells showed increased radiation-induced apoptosis, accompanied by faster growth rate, rather than and earlier radiation-induced G2/M phase arrest, suggesting that the radioresistance of NIH3T3-R1 and R4 cells was due to faster growth rate, rather than induction of apoptosis. In the case of MDM2 and CDC25B overexpressing cells, similar phenomena, such as increased apoptosis and faster growth rate, were shown. The above results, therefore, demonstrate involvement of CDC25B and MDM2 overexpression in radiation-induced tumorigenesis and provide novel targets for detection of radiation-induced carcinogenesis.

  16. The effects of cysteamine on the radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Choi, Young Min; Cho, Heung Lae; Park, Chang Gyo; Lee, Hyung Sik; Hur, Won Joo

    2000-01-01

    To investigate the pathways of radiation induced apoptosis and the effect of cysteamine (β-mercaptoethylamine), as a radioprotector, on it. HL-60 cells were assigned to control, irradiated, and cysteamine (1 mM, 10 mM) pretreated groups. Irradiation was given in a single fraction of 10 Gy (6 MV x-ray) and cysteamine was administered 1 hour before irradiation. The activities of caspase-8 were measured in control and irradiated group to evaiuate its relation to the radiation induced apoptosis. To evaluate the role of cysteamine in radiation induced apoptosis, the number of viable cells, the expression and activity or caspase-3, and the expression of poly (ADP-ribose) polymerase (PARP) were measured and compared after irradiating the HL cells with cysteamine pretreatment or not. The intracellular caspase-8 activity, known to be related to the death receptor induced apoptosis, was not affected by irradiation( p>0.05). The number of viable cells began to decrease from 6 hours after irradiation (p>0.05), but the number of viable cells in 1 mM cysteamine pretreated group was not decreased after irradiation and was similar to those in the control group. In caspase-3 analyses, known as apoptosis executioner, its expression was not different but its activity was increased by irradialion(p>0.05). However, this increase of activity was suppressed by the pretreatment of 1 mM cysteamine. The cleavage of PARP, thought to be resulted from caspase-3 activation, occurred, after irradiation, which was attenuated by the pretreatment of 1 mM cysteamine. These results show that radiation induced apoptotic process is somewhat different from death receptor induced one and the pretreatment of 1 mM cysteamine has a tendency to decrease the radiation-induced apoptosis in HL-60 cells

  17. Radiation-induced cancers of the head and neck, (3)

    International Nuclear Information System (INIS)

    Umatani, Katsunori; Satoh, Takeo; Yoshino, Kunitoshi; Takagi, Tadashi; Fujii, Takashi; Hatta, Chihiro; Maetani, Chikahide; Lu, Bo

    1989-01-01

    This paper discusses twenty patients with radiation-induced cancers of the head and neck treated in the Department of Otorhinolaryngology, the Center for Adult Diseases, Osaka, from January 1979 to December 1985. The most common site of radiation-induced cancers was the hypopharynx and cervical esophagus (70%). We found synchronous double cancers in 2 out of the 20 patients (10%). One patient had hypopharyngeal cancer and thyroid cancer, and the other had oropharyngeal cancer and thyroid cancer. All of the laryngeal cancers were in the supraglottic area. Cancer of the hypopharynx and cervical esophagus occurred more frequently in females (1:3.7 males-females ratio). Half of the patients (10/20) had received irradiation for tuberculous cervical adenitis and 8 patients had been irradiated for malignant tumors. The averaged latent period in the patients who had irradiated for benign conditions was 37.4 years, and that for malignant diseases was 16.0 years. Therefore the latent period of the former was 2.3 times as long as that of the latter. The incidence of radiation-induced cancers in all the patients who had the cancer of the hypopharynx and cervical esophagus was 9% and that of the laryngeal cancer was 0.7%. The incidence of radiation-induced cancers in the hypopharynx and cervical esophagus remarkably differed from that in the larynx. However, it was suggested that the larynx was as resistant to radiation induction as the hypopharynx. Six of the 20 patients (30%) had radiation-induced thyroid tumors. Among them, the incidence of cancers was 33%. (author)

  18. Protective effect of Asparagus racemosus root extract against lethal total - body electron beam radiation induced damage in Swiss albino mice

    International Nuclear Information System (INIS)

    Sharmila, K.P.; Bhandary, B. Satheesh Kumar; Suchetha Kumari, N.; Bhat, Vadish S.; Shetty, Jayaram; Peter, Alex John; Jose, Jerish M.; Fernandes, Ronald

    2016-01-01

    To investigate the protective effect of Asparagus Racemosus Root ethanolic extract (ARE) in Swiss albino mice against acute lethal total - body Electron beam irradiation. Swiss Albino mice were used for the assessment of radiation induced sickness and 30 day survival analysis. Survival studies were determined using the Kaplan-Meier survival curves. The maximum survival was observed in the experimental mice pretreated with 200 mg/kg.b.wt. of ARE which also reduced the radiation sickness characteristics. This dose was considered as an optimal dose for radioprotection. Treatment of mice with ARE before irradiation delayed the onset of mortality as compared with the untreated irradiated controls. Present findings demonstrate the potential of ARE in mitigating radiation-induced mortality, which may be attributed to its free radical scavenging and increased antioxidant potential

  19. Development and Characterization of VEGF165-Chitosan Nanoparticles for the Treatment of Radiation-Induced Skin Injury in Rats

    Directory of Open Access Journals (Sweden)

    Daojiang Yu

    2016-10-01

    Full Text Available Radiation-induced skin injury, which remains a serious concern in radiation therapy, is currently believed to be the result of vascular endothelial cell injury and apoptosis. Here, we established a model of acute radiation-induced skin injury and compared the effect of different vascular growth factors on skin healing by observing the changes of microcirculation and cell apoptosis. Vascular endothelial growth factor (VEGF was more effective at inhibiting apoptosis and preventing injury progression than other factors. A new strategy for improving the bioavailability of vascular growth factors was developed by loading VEGF with chitosan nanoparticles. The VEGF-chitosan nanoparticles showed a protective effect on vascular endothelial cells, improved the local microcirculation, and delayed the development of radioactive skin damage.

  20. Radiation-induced camptocormia and dropped head syndrome. Review and case report of radiation-induced movement disorders

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Clemens; Kuhnt, Thomas; Kortmann, Rolf-Dieter; Hering, Kathrin [Leipzig University, Department of Radiotherapy and Radiation Oncology, Leipzig (Germany)

    2015-10-15

    In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.) [German] In den letzten Jahren haben Bewegungsstoerungen von Wirbelsaeule und paraspinaler Muskulatur in

  1. A study of radiation-induced cerebral vascular injury in nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis.

    Directory of Open Access Journals (Sweden)

    Jianhong Ye

    Full Text Available To investigate radiation-induced carotid and cerebral vascular injury and its relationship with radiation-induced temporal lobe necrosis in nasopharyngeal carcinoma (NPC patients.Fifty eight NPC patients with radiation-induced temporal lobe necrosis (TLN were recruited in the study. Duplex ultrasonography was used to scan bilateral carotid arterials to evaluate the intima-media thickness (IMT and occurrence of plaque formation. Flow velocities of bilateral middle cerebral arteries (MCAs, internal carotid arteries (ICAs and basal artery (BA were estimated through Transcranial Color Doppler (TCD. The results were compared with data from 33 patients who were free from radiation-induced temporal lobe necrosis after radiotherapy and 29 healthy individuals.Significant differences in IMT, occurrence of plaques of ICAs and flow velocities of both MCAs and ICAs were found between patients after radiotherapy and healthy individuals (p<0.05. IMT had positive correlation with post radiation interval (p = 0.049. Compared with results from patients without radiation-induced TLN, the mean IMT was significantly thicker in patients with TLN (p<0.001. Plaques were more common in patients with TLN than patients without TLN (p = 0.038. In addition, flow velocities of MCAs and ICAs in patients with TLN were much faster (p<0.001, p<0.001. Among patients with unilateral TLN, flow velocity of MCAs was significantly different between ipsilateral and contralateral sides to the lesion (p = 0.001.Thickening of IMT, occurrence of plaque formation and hemodynamic abnormality are more common in patients after radiotherapy, especially in those with TLN, compared with healthy individuals.

  2. Botulinum Toxin Confers Radioprotection in Murine Salivary Glands

    Energy Technology Data Exchange (ETDEWEB)

    Zeidan, Youssef H., E-mail: zeidan@miami.edu [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Xiao, Nan; Cao, Hongbin [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Kong, Christina [Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California (United States); Department of Pathology, Stanford University School of Medicine, Stanford, California (United States); Le, Quynh-Thu; Sirjani, Davud [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States)

    2016-04-01

    Purpose: Xerostomia is a common radiation sequela, which has a negative impact on the quality of life of patients with head and neck cancer. Current treatment strategies offer only partial relief. Botulinum toxins (BTX) have been successfully used in treating a variety of radiation sequelae such as cystitis, proctitis, fibrosis, and facial pain. The purpose of this study was to evaluate the effect of BTX on radiation-induced salivary gland damage. Methods and Materials: We used a previously established model for murine salivary gland irradiation (IR). The submandibular glands (SMGs) of C5BL/6 mice (n=6/group) were injected with saline or BTX 72 hours before receiving 15 Gy of focal irradiation. Saliva flow was measured 3, 7, and 28 days after treatment. The SMGs were collected for immunohistochemistry, confocal microscopy, and Western blotting. A cytokine array consisting of 40 different mouse cytokines was used to evaluate cytokine profiles after radiation treatment. Results: Irradiated mice showed a 50% reduction in saliva flow after 3 days, whereas mice preinjected with BTX had 25% reduction in saliva flow (P<.05). Cell death detected by TUNEL staining was similar in SMG sections of both groups. However, neutrophil infiltrate, detected by myeloperoxidase staining, was 3-fold lower for the BTX treated mice. A cytokine array showed a 2-fold upregulation of LPS-induced chemokine (LIX/CXCL5) 3 days after IR. BTX pretreatment reduced LIX levels by 40%. At 4 weeks after IR, the saline (control) group showed a 40% reduction in basal SMG weight, compared with 20% in the BTX group. Histologically, BTX-pretreated glands showed relative preservation of acinar structures after radiation. Conclusions: These data suggest that BTX pretreatment ameliorates radiation-induced saliva dysfunction. Moreover, we demonstrate a novel role for CXCL5 in the acute phase of salivary gland damage after radiation. These results carry important clinical implications for the treatment of

  3. Treatment of Radiation Induced Biological Changes by Bone Marrow Transplantation

    International Nuclear Information System (INIS)

    El-Missiry, M.A.; Shehata, G.; Roushdy, H.M; Fayed, Th.A.

    1999-01-01

    Preventing the propagation of radiation induced oxidative damage has been a subject of considerable investigations. The ultimate goal of the present study is to use bone marrow cells to ameliorate or to treat the radiation sickness. Transplantation of bone marrow cell has shown promising results in the present experimental radiation treatment. In this report, suspension of bone marrow cells was injected into rats 12 h. after exposure to 4.5 Gy whole body gamma irradiation. Significant results were recorded on the successful control of the radiation induced disorders in a number of biochemical parameters including certain enzymatic and nonenzymatic antioxidants (superoxide dismutase and glutathione) and certain parameters related to kidney function including creatinine, urea as well as Atpase Activity in blood serum, urine and kidney tissue

  4. A case of radiation-induced cancer of the hypopharynx

    International Nuclear Information System (INIS)

    Miyamoto, Kouji; Shimizu, Yukio; Yura, Jirou; Itoh, Yasufumi; Ikeda, Tsuneko; Outsubo, Toshio; Saitou, Hitoshi

    2001-01-01

    We report a case of radiation-induced cancer of the hypopharynx in a 65-year-old woman. The patient had received radiation treatment for Basedow's disease for several years starting at the age of 10 years. On June 26, 1993, she was examined at our hospital because of hoarseness and dysphagia. On July 22, right lobectomy was performed for suspected thyroid cancer. During this operation, endoscopy revealed hypopharyngeal cancer. Twenty-two days after surgery, total pharyngolaryngectomy and total esophagectomy were performed and a pharyngogastrostomy and a permanent tracheostomy were created. Histologic examination revealed moderately differentiated squamous cell cancer. This case was diagnosed as radiation-induced caner according to the diagnostic criteria of Sakai. (author)

  5. Radiation Induced Color Centers in a La Doped PWO Crystal

    CERN Document Server

    Deng, Qun

    1998-01-01

    This report presents result of a study on radiation induced color center densities in a La doped lead tungstate ( PWO) crystal. The creation and annihilation constants of radiation induced color centers were determined by using transmittance data measured for a PWO sample before and during Co-60 gamma ray irradiation at a dose rate of 15 rad/hr. Following a model of color center kinetics, these constants were used to calculate color center densities under irradiations at 100 rad/hr. The result was found to be in a good agreement with experimental data, indicating that this model of color center kinetics can be used to predict behavior of PWO crystals under irradiation.

  6. Depleted uranium and radiation - induced lung cancer and leukaemia

    International Nuclear Information System (INIS)

    Mould, R.F.

    2002-01-01

    Reports of leukaemias and other cancers among servicemen who took part in the 1991 Gulf war or in the more recent operations in the Balkans are of continuing interest, as is the possibility, however slight, that depleted uranium (DU) is one of the causative factors. This commentary includes the results of a UK epidemiological study on the mortality of Gulf war veterans and , although not containing information on DU exposure, gives data on overall levels of mortality and therefore carries more weight than anecdotal reports. Also included are brief summaries on radiation-induced lung cancer in uranium workers as well as radiation-induced leukaemia in Japanese atomic bomb survivors and patients ankylosing spondylitis treated using x-rays. This commentary concludes with a critique of Iraqi cancer statistics as well as giving information on environmental contamination in Kosovo and the use of DU ammunition. (author)

  7. Caffeine Markedly Enhanced Radiation-Induced Bystander Effects

    International Nuclear Information System (INIS)

    Jiang Erkang; Wu Lijun

    2009-01-01

    In this paper it is shown that incubation with 2 mM caffeine enhanced significantly the MN (micronucleus) formation in both the 1 cGy α-particle irradiated and non-irradiated bystander regions. Moreover, caffeine treatment made the non-irradiated bystander cells more sensitive to damage signals. Treated by c-PTIO(2-(4-carboxy-phenyl)- 4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), a nitric oxide (NO) scavenger, the MN frequencies were effectively inhibited, showing that nitric oxide might be very important in mediating the enhanced damage. These results indicated that caffeine enhanced the low dose α-particle radiation-induced damage in irradiated and non-irradiated bystander regions, and therefore it is important to investigate the relationship between the radiosensitizer and radiation-induced bystander effects (RIBE). (ion beam bioengineering)

  8. Computer modelling of radiation-induced bystander effect

    International Nuclear Information System (INIS)

    Khvostunov, Igor K.; Nikjoo, Hooshang

    2002-01-01

    Radiation-induced genomic instability and bystander effects are now well established consequences of exposure of living cells to ionising radiation. It has been observed that cells not directly hit by radiation tracks may still exhibit radiation effects. We present a quantitative modelling of the radiation-induced bystander effect based on a diffusion model of spreading the bystander signal. The model assumes the bystander factor to be a protein of low molecular weight, given out by the hit cell, diffusing in the medium and reacting with non-hit cells. The model calculations successfully predict the results of cell survival in an irradiated conditioned medium. The model predicts the shape of dose-effect relationship for cell survival and oncogenic transformation induced by broad-beam and micro-beam irradiation by alpha-particles. (author)

  9. Radiation induced sarcomas of bone following therapeutic radiation

    International Nuclear Information System (INIS)

    Kim, J.H.; Chu, F.C.H.; Woodward, H.Q.; Huvos, A.

    1983-01-01

    Because of new therapeutic trends of multi-modality and the importance of late effects, we have updated our series of radiation induced bone sarcomas seen at Memorial Sloan-Kettering Cancer Center over the past four decades. A total of 37 cases of bone sarcoma arising from normal bone in the irradiated field was analyzed. The median for latent period from irradiation to diagnosis of bone sarcoma was 11 years with a minimum latent period of four years. The median radiation dose for the bone sarcoma was 6000 rad in 6 weeks with a minimum total radiation dose of 3000 rad in 3 weeks. We have found nine patients who developed bone sarcomas in the radiation field after successful treatment of Hodgkin's disease. Criteria for radiation induced bone sarcomas and the magnitude of the risk of bone sarcomas are briefly discussed

  10. Radiation-induced soft-tissue and bone sarcoma

    International Nuclear Information System (INIS)

    Kim, J.H.; Chu, F.C.; Woodard, H.Q.; Melamed, R.; Huvos, A.; Cantin, J.

    1978-01-01

    From the records of Memorial Hospital of the past 50 years, 47 cases with an established diagnosis of radiation-induced sarcoma were identified and divided into two groups: the first included 20 cases of soft-tissue sarcoma arising from irradiated tissues, and the second comprised 27 cases of bone sarcoma arising from normal bones in the irradiated field. Medians for the latent periods from irradiation to diagnosis of bone and soft-tissue sarcoma were 11 and 12, years, respectively. In bone sarcomas, the latent period was longer after larger radiation doses and children appeared to be more susceptible to cancer induction than adults. Criteria for establishing the diagnosis of radiation-induced sarcoma and the magnitude of the risk of bone sarcoma are discussed

  11. Radiation-induced tritium labelling and product analysis

    Energy Technology Data Exchange (ETDEWEB)

    Peng, C.T. (California Univ., San Francisco, CA (United States). Dept. of Pharmaceutical Chemistry)

    1993-05-01

    By-products formed in radiation-induced tritium labelling are identified by co-chromatography with authentic samples or by structure prediction using a quantitative structure-retention index relationship. The by-products, formed from labelling of steroids, polynuclear aromatic hydrocarbons, 7-membered heterocyclic ring structures, 1,4-benzodiazepines, 1-haloalkanes, etc. with activated tritium and adsorbed tritium, are shown to be specifically labelled and anticipated products from known chemical reactions. From analyses of the by-products, one can conclude that the hydrogen abstraction by tritium atoms and the substitution by tritium ions are the mechanisms of labelling. Classification of the tritium labelling methods, on the basis of the type of tritium reagent, clearly shows the active role played by tritium atoms and ions in radiation-induced methods. (author).

  12. Radiation induced graft copolymerization of acrylamide onto poly (3-hydroxybutyrate)

    International Nuclear Information System (INIS)

    Gonzalez Torres, Maykel; Rapado Paneque, Manuel; Paredes Zaldivar, Mayte; Altanes Valentin, Sonia; Barrera Gonzalez, Gisela

    2008-01-01

    The graft copolymer poly (3-hydroxybutyrate)-g- polyacrylamide [P (HB-g-AAm)] was synthesized by radiation induced graft copolymerization of acrylamide onto poly (3-hydroxybutyrate). The study was conducted by the simultaneous irradiation method. The structure of [P (HB-g-AAm)] was identified by Fourier Transform Infrared (FTIR) spectroscopy. Thermal behavior of the graft copolymer was also studied by Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). From the results it was found that FTIR studies showed new signals (stretching -N-H) as strong evidence of grafting. The grafting degree was found to be 10 % and the thermodynamic parameter obtained from the DSC thermogram of plain PHB and the graft copolymer varied showing decrease in the material crystallinity and increase in the glass transition temperature. These results demonstrate that the radiation induced graft copolymerization reaction of acrylamide onto PHB was successively achieved. (Author)

  13. A case of radiation-induced cancer of the hypopharynx

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Kouji; Shimizu, Yukio; Yura, Jirou; Itoh, Yasufumi; Ikeda, Tsuneko [Matsunami General Hospital, Kasamatsu, Gifu (Japan); Outsubo, Toshio; Saitou, Hitoshi

    2001-06-01

    We report a case of radiation-induced cancer of the hypopharynx in a 65-year-old woman. The patient had received radiation treatment for Basedow's disease for several years starting at the age of 10 years. On June 26, 1993, she was examined at our hospital because of hoarseness and dysphagia. On July 22, right lobectomy was performed for suspected thyroid cancer. During this operation, endoscopy revealed hypopharyngeal cancer. Twenty-two days after surgery, total pharyngolaryngectomy and total esophagectomy were performed and a pharyngogastrostomy and a permanent tracheostomy were created. Histologic examination revealed moderately differentiated squamous cell cancer. This case was diagnosed as radiation-induced caner according to the diagnostic criteria of Sakai. (author)

  14. Radiation-induced malignant tumours: a specific cytogenetic profile?

    International Nuclear Information System (INIS)

    Chauveinc, L.; Gaboriaux, G.; Dutrillaux, A. M.; Dutrillaux, B.; Chauveinc, L.; Ricoul, M.; Sabatier, L.; Dutrillaux, B.

    1997-01-01

    To date, there is no criterion enabling to determine the spontaneous or radio-induced origin of malignant tumour occurring in a previously irradiated patient. Biological studies are rare. The cytogenetic data which could be found in the literature for eleven radio-induced tumours suggest that aneuploidies and polyclonality are frequent events. We studied, by R-Banding cytogenetic technique, five patients with short-term cultures (3 cases), short and long-term cultures (1 case) and xeno-grafting on nude pattern a high rate of balanced translocations, numerous random break points and a polyclonal evolution (10 clones). All other tumours, including the xeno-grafting sarcoma, had a monoclonal profile with complex karyotypes, hypo-diploid formulas and many deletions. These results show that the mechanism of radiation-induced tumours frequently involves chromosomes losses and deletions. The most likely explanation is that these alterations unmask radiation induced recessive mutations of tumour suppressor genes. (authors)

  15. Radiation induced DNA damage and repair in mutagenesis

    International Nuclear Information System (INIS)

    Strniste, G.F.; Chen, D.J.; Okinaka, R.T.

    1987-01-01

    The central theme in cellular radiobiological research has been the mechanisms of radiation action and the physiological response of cells to this action. Considerable effort has been directed toward the characterization of radiation-induced DNA damage and the correlation of this damage to cellular genetic change that is expressed as mutation or initiating events leading to cellular transformation and ultimately carcinogenesis. In addition, there has been a significant advancement in their understanding of the role of DNA repair in the process of mutation leading to genetic change in cells. There is extensive literature concerning studies that address radiation action in both procaryotic and eucaryotic systems. This brief report will make no attempt to summarize this voluminous data but will focus on recent results from their laboratory of experiments in which they have examined, at both the cellular and molecular levels, the process of ionizing radiation-induced mutagenesis in cultured human cells

  16. Ubiquitin-dependent system controls radiation induced apoptosis

    International Nuclear Information System (INIS)

    Delic, J.; Magdelenat, H.; Glaisner, S.; Magdelenat, H.; Maciorowski, Z.

    1997-01-01

    The selective proteolytic pathway, dependent upon 'N-end rule' protein recognition/ubiquitination and on the subsequent proteasome dependent processing of ubiquitin conjugates, operates in apoptosis induced by γ-irradiation. The proteasome inhibitor peptide aldehyde, MG132, efficiently induced apoptosis and was also able (at doses lower than those required for apoptosis induction) to potentiate apoptosis induced by DNA damage. Its specificity is suggested by the induction of the ubiquitin (UbB and UbC) and E1 (ubiquitin activating enzyme) genes and by an altered ubiquitination pattern. More selectively, a di-peptide competitor of the 'N-end rule' of ubiquitin dependent protein processing inhibited radiation induced apoptosis. This inhibition is also followed by an altered ubiquitination pattern and by activation of Poly (ADP-ribose) polymerase (PARP). These data strongly suggest that early apoptosis radiation induced events are controlled by ubiquitin-dependent proteolytic processing. (author)

  17. 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

  18. Platelet-derived growth factor (PDGF)-signaling mediates radiation-induced apoptosis in human prostate cancer cells with loss of p53 function

    International Nuclear Information System (INIS)

    Kim, Harold E.; Han, Sue J.; Kasza, Thomas; Han, Richard; Choi, Hyeong-Seon; Palmer, Kenneth C.; Kim, Hyeong-Reh C.

    1997-01-01

    Platelet-derived growth factor (PDGF) signals a diversity of cellular responses in vitro, including cell proliferation, survival, transformation, and chemotaxis. PDGF functions as a 'competence factor' to induce a set of early response genes expressed in G 1 including p21 WAF1/CIP1 , a functional mediator of the tumor suppressor gene p53 in G 1 /S checkpoint. For PDGF-stimulated cells to progress beyond G 1 and transit the cell cycle completely, progression factors in serum such as insulin and IGF-1 are required. We have recently shown a novel role of PDGF in inducing apoptosis in growth-arrested murine fibroblasts. The PDGF-induced apoptosis is rescued by insulin, suggesting that G 1 /S checkpoint is a critical determinant for PDGF-induced apoptosis. Because recent studies suggest that radiation-induced signal transduction pathways interact with growth factor-mediated signaling pathways, we have investigated whether activation of the PDGF-signaling facilitates the radiation-induced apoptosis in the absence of functional p53. For this study we have used the 125-IL cell line, a mutant p53-containing, highly metastatic, and hormone-unresponsive human prostate carcinoma cell line. PDGF signaling is constitutively activated by transfection with a p28 v-sis expression vector, which was previously shown to activate PDGF α- and β- receptors. Although the basal level of p21 WAF1/CIP1 expression and radiation-induced apoptosis were not detectable in control 125-IL cells as would be predicted in mutant p53-containing cells, activation of PDGF-signaling induced expression of p21 WAF1/CIP1 and radiation-induced apoptosis. Our study suggests that the level of 'competence' growth factors including PDGF may be one of the critical determinants for radiation-induced apoptosis, especially in cells with loss of p53 function at the site of radiotherapy in vivo

  19. Regulation of radiation-induced protein kinase Cδ activation in radiation-induced apoptosis differs between radiosensitive and radioresistant mouse thymic lymphoma cell lines

    International Nuclear Information System (INIS)

    Nakajima, Tetsuo; Yukawa, Osami; Tsuji, Hideo; Ohyama, Harumi; Wang, Bing; Tatsumi, Kouichi; Hayata, Isamu; Hama-Inaba, Hiroko

    2006-01-01

    Protein kinase Cδ (PKCδ) has an important role in radiation-induced apoptosis. The expression and function of PKCδ in radiation-induced apoptosis were assessed in a radiation-sensitive mouse thymic lymphoma cell line, 3SBH5, and its radioresistant variant, XR223. Rottlerin, a PKCδ-specific inhibitor, completely abolished radiation-induced apoptosis in 3SBH5. Radiation-induced PKCδ activation correlated with the degradation of PKCδ, indicating that PKCδ activation through degradation is involved in radiation-induced apoptosis in radiosensitive 3SBH5. In radioresistant XR223, radiation-induced PKCδ activation was lower than that in radiosensitive 3SBH5. Cytosol PKCδ levels in 3SBH5 decreased markedly after irradiation, while those in XR223 did not. There was no apparent change after irradiation in the membrane fractions of either cell type. In addition, basal cytosol PKCδ levels in XR223 were higher than those in 3SBH5. These results suggest that the radioresistance in XR223 to radiation-induced apoptosis is due to a difference in the regulation of radiation-induced PKCδ activation compared to that of 3SBH5. On the other hand, Atm -/- mouse thymic lymphoma cells were more radioresistant to radiation-induced apoptosis than wild-type mouse thymic lymphoma cells. Irradiated wild-type cells, but not Atm -/- cells, had decreased PKCδ levels, indicating that the Atm protein is involved in radiation-induced apoptosis through the induction of PKCδ degradation. The decreased Atm protein levels induced by treatment with Atm small interfering RNA had no effect on radiation-induced apoptosis in 3SBH5 cells. These results suggest that the regulation of radiation-induced PKCδ activation, which is distinct from the Atm-mediated cascade, determines radiation sensitivity in radiosensitive 3SBH5 cells

  20. Study of radiation induced structural changes in nitrile rubber

    International Nuclear Information System (INIS)

    Cardona, F.; Hill, D.J.T.; Pomery, P.J.; Whittaker, A.K.

    1996-01-01

    Full text: Copolymers of butadiene (BD) and acrylonitrile (AN) (NBR rubber), have become important commercial material. NBR rubbers are part of a larger classification of products often referred to as special-purpose rubbers. Oil resistance is the most important property of nitrile rubbers, and refer to the ability of the vulcanised product to retain its original physical properties such as modulus, tensile strength, abrasion resistance and dimensions, while in contact with oils and fuels. Despite these reported advantages very few studies have been conducted on the radiation yields and structural changes in nitrile rubbers during exposure to high energy radiation. In this study we are investigating the stability against gamma and UV radiation, to different doses in vacuum, of butadiene, acrylonitrile and NBR copolymers with different composition ratio BD/AN. The mechanism of radiation induced structural changes is being investigated using experimental techniques such as ESR, NMR (Solid-state), FT-IR, RAMAN and UV spectroscopy. Also is being investigated the effect of irradiation on the mechanical properties of stressed and unstressed samples by TGA, DSC, DMA, Instron and Creep Test measurements. So far the main effect have been a marked radiation-induced loss of unsaturation in the butadiene units, cis to trans isomerization and formation of crosslink structures (intermolecular and intramolecular). One of the main challenges in the studies of NBR polymers is to observe directly the crosslinks produces by the radiation induced chemical reactions. IR spectroscopy is unsuitable because of the low molar absorbity of the peaks related to intermolecular crosslinking and the overlapping of the peaks (1630-1670 cm-1) related to intramolecular crosslinking (cyclization), with conjugated and nonconjugated (-C=C-; -C=N-) double bonds. A. K. Whittaker has shown that crosslink structures in PBD can be detected and measured directly using solid-state 13 C NMR. This technique

  1. Heavy-ion radiation induced bystander effect in mice

    Science.gov (United States)

    Liang, Shujian; Sun, Yeqing; Zhang, Meng; Wang, Wei; Cui, Changna

    2012-07-01

    Radiation-induced bystander effect is defined as the induction of damage in neighboring non-hit cells by signals released from directly-irradiated cells. Recently, Low dose of high LET radiation induced bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. Genomic, epigenetic, metabolomics and proteomics play significant roles in regulating heavy-ion radiation stress responses in mice. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male mice head were exposed to 2000mGy dose of 12C heavy-ion radiation and the distant organ liver was detected on 1h, 6h, 12h and 24h after radiation, respectively. MSAP was used to monitor the level of polymorphic DNA methylation changes. The results show that heavy-ion irradiate mouse head can induce liver DNA methylation changes significantly. The percent of DNA methylation changes are time-dependent and highest at 6h after radiation. We also prove that the hypo-methylation changes on 1h and 6h after irradiation. But the expression level of DNA methyltransferase DNMT3a is not changed. UPLC/Synapt HDMS G2 was employed to detect the proteomics of bystander liver 1h after irradiation. 64 proteins are found significantly different between treatment and control group. GO process show that six of 64 which were unique in irradiation group are associated with apoptosis and DNA damage response. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in distant organ liver. Moreover, our findings are important to understand the molecular mechanism of radiation induced bystander effects in vivo.

  2. [The occupational radiation-induced cataract in five industrial radiographers].

    Science.gov (United States)

    Benzarti Mezni, A; Loukil, I; Hriz, N; Kallel, K; Mlaiki, N; Ben Jemaâ, A

    2012-04-01

    The industrial uses of ionizing radiation in Tunisia are expanding, especially in industry and most particularly in the nondestructive testing of welds. Thus workers operating in the non-destructive testing of welds may develop a radiation-induced cataract varying in time to onset depending on the dose. To describe the characteristics of the radiation-induced cataract in patients exposed to ionizing radiation, determine the risk factors of radiation-induced cataracts. This was an anamnestic, clinical, and environmental study of five cases of radiation-induced cataract in workers employed in non-destructive testing of welds. This series of five cases had a mean age of 30.2 years and 5.53 years of work experience, ranging from 14 months to 15 years. All the patients were male and industrial radiographers specialized in nondestructive testing of welds. The average duration of exposure to ionizing radiation was 5.53 years. None of the patients had worn protective gear such as eye goggles. The ophthalmic check-up for the five special industrial radiographers showed punctuate opacities in three cases, punctiform opacities in one eye in one case, and phacosclerosis with bilateral lens multiple crystalline stromal opacities in a case of micro-lens opacities in both eyes with opalescence of both eyes in one case. These cataracts had been declared as occupational diseases. The value of a specialized ophthalmologic surveillance among these workers and the early diagnosis of lens opacities must be emphasized. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  3. Radiation-induced transient absorption in single mode optical fibers

    International Nuclear Information System (INIS)

    Looney, L.D.; Lyons, P.B.

    1988-01-01

    This paper reviews the measurements conducted by the Los Alamos National Laboratory in support of these NATO efforts wherein radiation-induced transient absorption was measured over time ranges from a few ns to several μs for two single mode fibers. Experimental conditions were varied to provide data for future development of standarized test conditions for single mode fibers. 8 refs., 11 figs

  4. Radiation-induced morphea of the breast: a case report

    Directory of Open Access Journals (Sweden)

    Cheah Nellie LC

    2008-04-01

    Full Text Available Abstract Radiation-induced morphea (RIM of the breast is a rare complication of radiotherapy. It is disfiguring, painful and defeats the purpose of achieving a good cosmesis in breast-conservation surgery. This report describes a severe case of RIM in a breast cancer patient together with photographic illustrations of the serial changes over time and histopathology slides. A review of the literature is provided.

  5. Radiation-induced trioxane postpolymerization in the liquid phase

    International Nuclear Information System (INIS)

    Kapustina, I.B.; Starchenko, T.V.

    1979-01-01

    Radiation-induced trioxane postpolymerization in the presence of maleic anhydride and different solvents in the liquid phase has been studied. It has been found that addition of small quantities of different solvents inhibits the trioxane polymerization process both in the presence of maleic anhydride and in the absence of it. Trioxane postpolymerization in a solvent-nonsolvent mixture gives fibrous polyoxymethylene with high molecular mass and high yield

  6. Radiation induced structural changes in alpha-copper-zinc alloys

    International Nuclear Information System (INIS)

    Schuele, W.; Gieb, M.

    1991-01-01

    During irradiation of alpha-copper-zinc alloys with high energy electrons and protons a decrease of the electrical resistivity due to an increase of the degree of short range order is observed through radiation enhanced diffusion followed by an increase of the electrical resistivity through the formation of radiation induced interstitial clusters. The initial formation rate of interstitial clusters increases about linearly with the displacement rate for electron and proton irradiation. The largest initial formation rate is found between 60 and 130 0 C becoming negligibly small above 158 0 C and decreases drastically below 60 0 C. The dynamic steady state interstitial cluster concentration increases with decreasing irradiation temperature in the investigated temperature range between 158 and 40 0 C. Above 158 0 C the formation rate of interstitial clusters is negligibly small. Thus the transition temperature for radiation induced interstitial cluster formation is 158 0 C, depending mainly on the migration activation energy of vacancies. The radiation induced interstitial clusters are precipitates in those alloys in which the diffusion rate of the undersized component atoms via an interstitialcy diffusion mechanism is larger than that of the other atoms

  7. Protection against radiation-induced performance decrement in mice

    International Nuclear Information System (INIS)

    Mukherjee, S.K.; Pant, Kanchan; Goel, H.C.; Jain, Viney

    1997-01-01

    Recognizing that there is lack of information on the effects of low-level ionizing radiations and the modifying role of radioprotectors, an attempt has been made in this study to explore the relationship between impairment of spatial learning and low level of radiation exposure. A radial arm maze was utilised to evaluate radiation-induced behavioural alterations and performance decrement in mice. Immediately after whole body exposure to gamma radiation (absorbed dose, 1 Gy) significant perturbations in the learned behaviour of the animals were observed. The regular control movement became irregular and the food consumption time was reduced appreciably (40%). Recovery took place in four days. If diltiazem (7 mg/kg b.w.), a Ca 2+ channel blocker and a radioprotector, was administered i.p. 20-30 min prior to irradiation, radiation-induced behavioural abnormalities were reduced. Mechanisms underlying protection by diltiazem against radiation-induced performance decrement observed in the present study need to be investigated. (author). 23 refs., 2 figs

  8. Radiation-induced grain boundary segregation in austenitic stainless steels

    International Nuclear Information System (INIS)

    Bruemmer, S.M.; Charlot, L.A.; Vetrano, J.S.; Simonen, E.P.

    1994-11-01

    Radiation-induced segregation (RIS) to grain boundaries in Fe-Ni-Cr-Si stainless alloys has been measured as a function of irradiation temperature and dose. Heavy-ion irradiation was used to produce damage levels from 1 to 20 displacements per atom (dpa) at temperatures from 175 to 550 degrees C. Measured Fe, Ni, and Cr segregation increased sharply with irradiation dose (from G to 5 dpa) and temperature (from 175 to about 350 degrees C). However, grain boundary concentrations did not change significantly as dose or temperatures were further increased. Although interfacial compositions were similar, the width of radiation-induced enrichment or depletion profiles increased consistently with increasing dose or temperature. Impurity segregation (Si and P) was also measured, but only Si enrichment appeared to be radiation-induced. Grain boundary Si peaked at levels approaching 10 at% after irradiation doses to 10 dpa at an intermediate temperature of 325 degrees C. No evidence of grain boundary silicide precipitation was detected after irradiation at any temperature. Equilibrium segregation of P was measured in the high-P alloys, but interfacial concentration did not increase with irradiation exposure. Comparisons to reported RIS in neutron-irradiated stainless steels revealed similar grain boundary compositional changes for both major alloying and impurity elements

  9. Radiation-induced tumors of the nervous system

    International Nuclear Information System (INIS)

    Bernstein, M.; Laperriere, N.

    1991-01-01

    Therapeutic and nontherapeutic ionizing radiation has long been recognized as a putative carcinogenic agent, but the evidence that radiation causes tumors is circumstantial at worst and statistically significant at best. There are no distinct histological, biochemical, cytogenetic, or clinical criteria that can be used to determine if an individual tumor was caused directly by previous irradiation of the anatomic area. Additional supportive evidence for radiation-induced tumors includes a position correlation between radiation dose and tumor incidence (usually in the low dose range) and experimental induction of the same neoplasm in appropriate animal models. even if these criteria are fulfilled, coincidental development of a second tumor can never be discounted in an individual patient, particularly if there is an underlying diathesis to develop multiple tumors of different histology, such as in Recklinghausen's disease, or if there is an strong family history for the development of neoplastic disease. In this paper, the authors critically evaluate the available evidence to support the hypothesis that radiation induces tumors in the nervous system. The current concepts of radiation carcinogenesis are discussed and are followed by a discussion of animal data and clinical experience in humans. Finally, a brief discussion on treatment of radiation-induced nervous system tumors is presented

  10. Challenges in Clinical Management of Radiation-Induced Illnesses in Exploration Spaceflight

    Science.gov (United States)

    Blue, Rebecca; Chancellor, Jeffery; Suresh, Rahul; Carnell, Lisa; Reyes, David; Nowadly, Craig; Antonsen, Erik

    2018-01-01

    Historical solar particle events (SPEs) provide context for some understanding of acute radiation exposure risk to astronauts traveling outside of low Earth orbit. Modeling of potential doses delivered to exploration crewmembers anticipates limited radiation-induced health impacts, including prodromal symptoms of nausea, emesis, and fatigue, but suggests that more severe clinical manifestations are unlikely. Recent large animal-model research in space-analogs closely mimicking SPEs has identified coagulopathic events independent of the hematopoietic sequelae of higher radiation doses, similar in manifestation to disseminated intravascular coagulation (DIC). We explored the challenges of clinical management of radiation-related clinical manifestations, using currently accepted modeling techniques and anticipated physiological sequelae, to identify medical capabilities needed to successfully manage SPE-induced radiation illnesses during exploration spaceflight.

  11. Radiation-Induced Organizing Pneumonia: A Characteristic Disease that Requires Symptom-Oriented Management.

    Science.gov (United States)

    Otani, Keisuke; Seo, Yuji; Ogawa, Kazuhiko

    2017-01-27

    Radiation-induced organizing pneumonia (RIOP) is an inflammatory lung disease that is occasionally observed after irradiation to the breast. It is a type of secondary organizing pneumonia that is characterized by infiltrates outside the irradiated volume that are sometimes migratory. Corticosteroids work acutely, but relapse of pneumonia is often experienced. Management of RIOP should simply be symptom-oriented, and the use of corticosteroids should be limited to severe symptoms from the perspective not only of cost-effectiveness but also of cancer treatment. Once steroid therapy is started, it takes a long time to stop it due to frequent relapses. We review RIOP from the perspective of its diagnosis, epidemiology, molecular pathogenesis, and patient management.

  12. Experimental study of the occurence and properties of C-type retroviruses in radiation-induced osteosarcomas in mice

    International Nuclear Information System (INIS)

    Erfle, V.

    1981-01-01

    In the radiation induced osteosarcomas of the C 3 Hx101/F 1 -mouse C-type virus particles had been found regularly with a density of 1.16 g/cm 3 , with high molecular RNA, a reverse transcriptase and the murine group-specific antigen p 30. Osteosarcomas of the NMRI-mouse, however, had only p 30 protein and so-called intra-cisternal A-type particles. After 'in vitro' cultivation retroviruses had been liberated from the osteosarcoma cells of the C 3 Hx101/F 1 -mice as well as from the NMRI-mice type C. During the tumour latency period a virus expression of the C-type retroviruses had been found for a certain period in the first month after irradiation of the bone tissue had begun; then followed an antibody-reaction which continued to persist until the 8th month. Another virus expression was observed in the skeleton during the period when the osteosarcomas appeared. This virus expression was accompanied by a decrease in antibodies and a temporary increase of the viral p 30 protein in the serum. The viruses which had been isolated from the radiation induced osteosarcomas showed the properties which are typical for ecotropic C-type retroviruses of mice. After infection of new-born mice these viruses produced fibrosarcomas (C 3 Hx 101/F 1 -mice) or lymphomas and osteomas (NMRI-mice). The results make it obvious that the endogenetic C-type retroviruses participate in the formation of radiation-induced sarcomas in mice. (orig./MG) [de

  13. Efficacy of wheat germ oil in modulating radiation-induced heart damage in rats

    International Nuclear Information System (INIS)

    Said, U.Z.; Azab, Kh.Sh.

    2006-01-01

    Wheat Germ oil is a natural unrefined vegetable oil. It is an excellent source of vitamin E, octacosanol, linoleic and linolenic essential fatty acids, which may be beneficial in neutralizing the free oxygen radicals. This study was designed to investigate the cardio-protective efficacy of wheat germ oil, on radiation-induced oxidative damage in rat's heart. Wheat germ oil was supplemented by gavage to rats at a dose of 81 mg/ kg body wt for 10 successive days pre- and 7 successive days post-exposure to 7 Gy (single dose) of whole body gamma irradiation. The dose of wheat germ oil is equivalent to daily human nutritional supplementation quantity. The results revealed that whole body ?-irradiation of rats produced significant alterations in blood cells picture. The erythrocyte, leucocyte, platelet counts and hemoglobin levels decreased after irradiation. Also, radiation-induced biochemical disorders manifested by significant elevation in xanthine oxidase activity (XO) and thiobarbituric acid reactive substances (TBARS) level, with decrease in reduced glutathione (GSH) content in heart tissues, indicating depression in the antioxidant status. Serum lipid profile as total cholesterol, high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and triglycerides levels (TG) were significantly higher than normal control rats. Radiation exposure produced a significant rise in the activities of serum markers for heart damage as creatine phosphokinase (CPK), aspartate aminotransferase (AST) and lactic dehydrogenase (LDH) indicating acute cardiac toxicity. Moreover, the obtained results revealed abnormal electrophoretic pattern of LDH isoenzymes in the 7th day after exposure to gamma rays. Three bands only appear on the agarose film comparing with 4 bands in normal control rats. The rats that received wheat germ oil supplement showed significantly less severe damage and remarkable improvement in all of the measured parameters when compared to

  14. Radiation-induced pseudotumor following therapy for soft tissue sarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Lacey F.; Kransdorf, Mark J. [Mayo Clinic, Department of Radiology, Jacksonville, FL (United States); Buskirk, Steven J. [Mayo Clinic, Department of Radiation Oncology, Jacksonville, FL (United States); O' Connor, Mary I. [Mayo Clinic, Department of Orthopedic Surgery, Jacksonville, FL (United States); Menke, David M. [Mayo Clinic, Department of Pathology, Jacksonville, FL (United States)

    2009-06-15

    The purpose of this study was to describe the prevalence and imaging appearance of radiation induced pseudotumors in patients following radiation therapy for extremity soft tissue sarcomas. We retrospectively reviewed the serial magnetic resonance (MR) images of 24 patients following radiation therapy for extremity soft tissue sarcomas. A total of 208 exams were reviewed (mean, 8.7 exams per patient) and included all available studies following the start of radiation therapy. Exams were analyzed for the identification of focal signal abnormalities within the surgical bed suggesting local tumor recurrence. Histopathologic correlation was available in nine patients suspected of having local tumor recurrence. Additional information recorded included patient demographics, tumor type and location, radiation type, and dose. The study group consisted of 12 men and 12 women, having an average age of 63 years (range, 39-88 years). Primary tumors were malignant fibrous histiocytoma (n = 13), leiomyosarcoma (n = 6), liposarcoma (n = 3), synovial sarcoma (n = 1), and extraskeletal chondrosarcoma (n = 1). All lesions were high-grade sarcomas, except for two myxoid liposarcomas. Average patient radiation dose was 5,658 cGy (range, 4,500-8,040 cGy). Average follow-up time was 63 months (range, 3-204 months). Focal signal abnormalities suggesting local recurrence were seen in nine (38%) patients. Three of the nine patients with these signal abnormalities were surgically proven to have radiation-induced pseudotumor. The pseudotumors developed between 11 and 61 months following the initiation of radiation therapy (mean, 38 months), with an average radiation dose of 5,527 cGy (range, 5,040-6,500 cGy). MR imaging demonstrated a relatively ill-defined ovoid focus of abnormal signal and intense heterogeneous enhancement with little or no associated mass effect. MR imaging of radiation-induced pseudotumor typically demonstrates a relatively ill-defined ovoid mass-like focus of intense

  15. Effect of Fenugreek (Trigonella Foenum-Graecum) Supplementation on Radiation-Induced Oxidative Stress in Liver and Kidney of Rats

    Energy Technology Data Exchange (ETDEWEB)

    EI-Tawil, G A [Radiation Biology Department, National Centre for Radiation Research and Technology (NCRRT), Atomic Energy Authority, Cairo (Egypt)

    2009-07-01

    Whole body exposure to ionizing radiation provokes oxidative damage, organ dysfunction and metabolic disturbances. Fenugreek (Trigonella foenumgraecum L. Leguminosae), one of the oldest medicinal plants rich in polyphenolic compounds is known to possess antioxidant properties. The present study was designed to determine the possible protective effect of fenugreek, against {gamma}-radiation-induced oxidative stress in liver and kidney tissues of rats. In parallel, the alteration in the activity of serum alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), as markers of liver function, creatinine and urea levels as markers of kidney function. In addition, serum glucose and insulin levels were determined as markers for carbohydrate metabolism. Irradiated rats were whole body exposed to 3.5 Gy (Acute dose) {gamma}-radiations. Fenugreek-treated irradiated rats received 1g fenugreek seed powder/kg body weight/day, by gavages, during 7 days before irradiation. Animals were sacrificed on the 1 sl day after irradiation. The results obtained demonstrated that exposure to ionizing radiation induced significant decreases in SOD and CAT activities and GSH content associated to significant increase of TBARS levels in liver and kidney. Fenugreek treatment has significantly attenuated radiation-induced oxidative stress in both tissues, which was substantiated by the significant amelioration of serum ALP, AST and ALT activities, creatinine, urea, glucose, and insulin levels. It could be concluded that fenugreek would protect from oxidative damage and metabolic disturbances induced by ionizing irradiation.

  16. Effect of Fenugreek (Trigonella Foenum-Graecum) Supplementation on Radiation-Induced Oxidative Stress in Liver and Kidney of Rats

    International Nuclear Information System (INIS)

    EI-Tawil, G.A.

    2009-01-01

    Whole body exposure to ionizing radiation provokes oxidative damage, organ dysfunction and metabolic disturbances. Fenugreek (Trigonella foenumgraecum L. Leguminosae), one of the oldest medicinal plants rich in polyphenolic compounds is known to possess antioxidant properties. The present study was designed to determine the possible protective effect of fenugreek, against γ-radiation-induced oxidative stress in liver and kidney tissues of rats. In parallel, the alteration in the activity of serum alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), as markers of liver function, creatinine and urea levels as markers of kidney function. In addition, serum glucose and insulin levels were determined as markers for carbohydrate metabolism. Irradiated rats were whole body exposed to 3.5 Gy (Acute dose) γ-radiations. Fenugreek-treated irradiated rats received 1g fenugreek seed powder/kg body weight/day, by gavages, during 7 days before irradiation. Animals were sacrificed on the 1 sl day after irradiation. The results obtained demonstrated that exposure to ionizing radiation induced significant decreases in SOD and CAT activities and GSH content associated to significant increase of TBARS levels in liver and kidney. Fenugreek treatment has significantly attenuated radiation-induced oxidative stress in both tissues, which was substantiated by the significant amelioration of serum ALP, AST and ALT activities, creatinine, urea, glucose, and insulin levels. It could be concluded that fenugreek would protect from oxidative damage and metabolic disturbances induced by ionizing irradiation

  17. The Development of Countermeasures for Space Radiation Induced Adverse Health Effects

    Science.gov (United States)

    Kennedy, Ann

    human trials necessary to demonstrate "efficacy" for a beneficial effect on the long term adverse health effects of radiation, such as the development of cancer, cataracts, etc., is expected to take particularly long periods of time. To avoid the long time delay in the development of new drugs as countermeasures for radiation induced adverse health effects, the NSBRI Center for Acute Radiation Research (CARR) is currently focused on the use of drugs that have already been approved for human use by the FDA. Currently there are no approved countermeasures for external radiation exposure by the US Army or by NASA. The appropriate medications for symptoms of the Acute Radiation Syndrome (ARS) due to exposure to solar particle event (SPE) radiation are unknown, but there are medications appropriate for ARS symptoms caused by exposure to conventional ra-diation. The Armed Forces Radiobiology Research Institute (AFRRI) has medical guidelines for ARS medications (http://www.afrri.usuhs.mil/outreach/guidance.htm#policies), as does the US Dept. of Health and Human Services (the REMM (Radiation Event Medical Manage-ment) site (http://www.remm.nlm.gov). Supportive care when ARS symptoms develop include the administration of antimicrobial agents (which can include systemic antibiotics [especially those directed at gram-negative bacteria]), antiemetic agents, antidiarrheal agents, fluids, elec-trolytes, analgesic agents and topical burn creams (Waselenko, J.K. et al. Ann. Intern. Med. 140: 1037, 2004). For nausea and vomiting, serotonin receptor antagonists (5HT3 receptor antagonists) are very effective prophylaxis. There are two drugs that have been approved by the FDA (Zofran and Kytril) for radiation induced nausea and vomiting. Kytril (granisetron) is preferred by the US Army and is currently maintained in the US National Stockpile. Both of these drugs are known to stop retching and vomiting when given either before or after irradi-ation, even when vomiting and/or retching are

  18. Relationship between radiation induced activation of DNA repair genes and radiation induced apoptosis in human cell line A431

    International Nuclear Information System (INIS)

    Bom, Hee Seung; Min, Jung Jun; Kim, Kyung Keun; Choi, Keun Hee

    2000-01-01

    The purpose of this study was to evaluate the relationship between radiation-induced acivation of DNA repair genes and radiation induced apoptosis in A431 cell line. Five and 25 Gys of gamma radiation were given to A431 cells by a Cs-137 cell irradiator. Apoptosis was evaluated by flow cytometry using annexin V-fluorescein isothiocyanate and propidium iodide staining. The expression of DNA repair genes was evaluated by both Northern and Western blot analyses. The number of apoptotic cells increased with the increased radiation dose. It increased most significantly at 12 hours after irradiation. Expression of p53, p21, and ℎRAD50 reached the highest level at 12 hours after 5 Gy irradiation. In response to 25 Gy irradiation, ℎRAD50 and p21 were expressed maximally at 12 hours, but p53 and GADD45 genes showed the highest expression level after 12 hours. Induction of apoptosis and DNA repair by ionizing radiation were closely correlated. The peak time of inducing apoptosis and DNA repair was 12 hours in this study model. ℎRAD50, a recently discovered DNA repair gene, was also associated with radiation-induced apoptosis.=20

  19. Effect of aqueous extract of saffron (crocus sativus L.) against gamma radiation-induced skeletal muscles damage in rats

    International Nuclear Information System (INIS)

    El-Tahawy, N.A; Said, U.Z

    2010-01-01

    Muscular strength is important in sport as well as in daily activities. Reactive oxygen species (ROS) and oxidative damage are the most important factors in radiation-induced acute damage to muscle tissue. Saffron, obtained from dried stigmas of Crocus sativus L. (Iridaceae), is a highly valued spice, commonly used in flavouring and food colouring in different parts of the world and is known to possess the richest source of carotenoids. The present study was designed to investigate the efficacy of an aqueous extract of saffron to protect against radiation-induced oxidative damage in rat's skeletal muscle. Saffron was supplemented orally, via gavages to rats at a dose of 80 mg/ kg body wt/ day for 2 week pre- and 1 week post-exposure to 5 Gy (one shot dose) of whole body gamma-irradiation. Animals were sacrificed 1, 2 and 3 weeks post radiation exposure. The results revealed that whole body gamma-irradiation of rats induce oxidative stress in skeletal muscles obvious by significant elevation in the level of thiobarbituric acid reactive substances associated with significant decreases in superoxide dismutase and catalase activities. Also, radiation-induces skeletal muscles damage evidenced by significant decreases in the level of pyruvic acid, creatine phosphokinase, glutamate dehydrogenase and glucose-6-phosphate dehydrogenase activities as well as significant increases in lactic acid, total iron, and copper and calcium levels. Saffron treated-irradiated rats showed significantly less severe damage and remarkable improvement in all the measured parameters, compared to irradiated rats. It could be concluded that saffron by attenuating radiation-induced oxidative stress might play a role in maintaining skeletal muscle integrity.

  20. Construction of radiation - induced metastasis model in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Kuk; Jang, Su Jin; Kang, Sung Wook; Kim, Jae Sung; Hwang, Sang Gu; Kang, Joo Hyun [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2011-05-15

    In treatment of cancer, distant metastases are important limiting factor because an estimated 50% of all cancer patients will develop metastases, and the metastases are major causing of cancer treatment failure. Recently a few reports indicated {gamma}-radiation induced an increase of invasiveness of several cancer cells. In this study, we had tried to show the possibility that radiation could also induce metastasis in vivo system. To prove our hypothesis, we constructed primary tumor by using C6-TL transfectant cell line expressing HSV1-tk and firefly luciferase (fLuc), and then {gamma}-radiation was treated to xenografts locally. Treatment of {gamma}-radiation to primary C6-TL xenografts of mice reduced size of xenografts and elongated survival of mice than those of mock control mice. But we also show that {gamma}-radiation treatment was followed by the growth of dormant metastases in various organs including lung and intestine after 2-4 weeks of {gamma}-radiation treatment. When bioluminescence imaging indicated growth of tumor in organs in mice, we sacrificed the mice and repeat acquired bioluminescence imaging after repeatedly. These images presented tumor growth locations exactly in organs. Because metastatic tumor candidates have morphology of foci, biopsies were performed for histological analysis or PCR analysis to confirm metastases. In most foci, histological analysis indicated several features of typical cancer tissue and PCR analysis showed present of fLuc gene in metastases. Detection of fLuc gene in metastases indicated these foci were originated from primary C6-TL xenografts, and the results suggest that {gamma}-radiation could promote metastasis in vivo as well as in vitro system. Although we need to understand changes of intracellular signaling or physiological phenomena of the radiation-induced metastasis yet, these results also imply that {gamma}-radiation treatment only to cancer patients need to pay attention carefully, and development of new

  1. Radioprotective effects of melatonin on radiation-induced cataract

    International Nuclear Information System (INIS)

    Karslioglu, Ie.; Ertekin, M.V.; Taysi, S.; Kocer, Ie.; Sezen, O.; Koc, M.; Bakan, N.; Gepdiremen, A.

    2005-01-01

    One of the mechanisms proposed to explain lens opacification is the oxidation of crystallins, either by radiation or reactive oxygen species (ROS). It has been shown that melatonin has both an anti-peroxidative effect on several tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant role of melatonin (5 mg/kg/day) against radiation-induced cataract in the lens after total-cranium irradiation of rats with a single dose of 5 Gy. Sprague-Dawley rats were divided into four groups. Control group received neither melatonin nor irradiation. Irradiated rats (IR) and melatonin+irradiated rats (IR+Mel) groups were exposed to total cranium irradiation of 5 Gy in a single dose by using a cobalt-60 teletherapy unit. IR+Mel and melatonin (Mel) groups were administered 5 mg/kg melatonin daily by intraperitoneal injections during ten days. Chylack's cataract classification was used in this study. At the end of the 10 th day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes i.e. the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation level (malondialdehyde (MDA)). Irradiation significantly increased the MDA level, as an end product of lipid peroxidation, and also significantly decreased SOD and GSH-Px activity, emphasizing the generation of increased oxidative stress. Rats injected with melatonin only did not cause cataract formation. Melatonin supplementation with irradiation significantly increased the activity of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose enhanced cataract formation, and melatonin supplementation protected the lenses from radiation-induced cataract formation. Our results suggest that supplementing cancer patients with adjuvant therapy of melatonin may reduce patients suffering from toxic therapeutic regimens such as chemotherapy and/or radiotherapy and may provide

  2. Radiation-induced erectile dysfunction: Recent advances and future directions

    Directory of Open Access Journals (Sweden)

    Javed Mahmood, PhD

    2016-07-01

    Full Text Available Prostate cancer is one of the most prevalent cancers and the second leading cause of cancer-related deaths in men in the United States. A large number of patients undergo radiation therapy (RT as a standard care of treatment; however, RT causes erectile dysfunction (radiation-induced erectile dysfunction; RiED because of late side effects after RT that significantly affects quality of life of prostate cancer patients. Within 5 years of RT, approximately 50% of patients could develop RiED. Based on the past and current research findings and number of publications from our group, the precise mechanism of RiED is under exploration in detail. Recent investigations have shown prostate RT induces significant morphologic arterial damage with aberrant alterations in internal pudendal arterial tone. Prostatic RT also reduces motor function in the cavernous nerve which may attribute to axonal degeneration may contributing to RiED. Furthermore, the advances in radiogenomics such as radiation induced somatic mutation identification, copy number variation and genome-wide association studies has significantly facilitated identification of biomarkers that could be used to monitoring radiation-induced late toxicity and damage to the nerves; thus, genomic- and proteomic-based biomarkers could greatly improve treatment and minimize arterial tissue and nerve damage. Further, advanced technologies such as proton beam therapy that precisely target tumor and significantly reduce off-target damage to vital organs and healthy tissues. In this review, we summarize recent advances in RiED research and novel treatment modalities for RiED. We also discuss the possible molecular mechanism involved in the development of RiED in prostate cancer patients. Further, we discuss various readily available methods as well as novel strategies such as stem cell therapies, shockwave therapy, nerve grafting with tissue engineering, and nutritional supplementations might be used to

  3. Radiation-induced rhabdomyosarcomatous transformation of a recurrent meningeal haemangiopericytoma

    International Nuclear Information System (INIS)

    Ka Kit Leung, G.; Chun Kit Lee, W.; Nicholls, J.M.

    2007-01-01

    A 53-year-old woman presented in 1979 with a posterior fossa meningeal haemangiopericytoma (HPC) for which she underwent surgical resection and post-operative radiotherapy. Repeated tumor recurrences occurred 18 years afterwards which were treated with resections and stereotactic radiotherapy. Surgery for tumor recurrence in 2005 revealed features of rhabdomyosarcomatous transformation. To our knowledge, this is the first reported case of rhabdomyosarcomatous transformation within a HPC which was likely to be radiation-induced, and was associated with relentless disease progression more than 20 years after the initial presentation. (author)

  4. Segregation effect of radiation induced crosslinking of HDPE: morphology change

    International Nuclear Information System (INIS)

    Deng Pengyang; Zhong Xiaoguang

    2000-01-01

    Scanning Electronic Microscopy has been used to study morphology of pure gel; sol-gel blend and sol-gel segregation samples of radiation induced crosslinking of HDPE. The results show that the morphology of segregation sample is the same as that of pure gel and different from that of sol-gel blend. This kind of morphology change proves that the sol-gel blend have occurred a liquid---solid phase segregation in the melting state. The liquid phase (sol) will naturally immersed in the network of the gel. (author)

  5. Radiation-induced hyperprolactinaemia in a treated acromegalic

    International Nuclear Information System (INIS)

    Shalet, S.M.; MacFarlane, I.A.; Beardwell, C.G.

    1979-01-01

    A 31-year-old acromegalic was normoprolactinaemic after partial removal of her pituitary tumour. The post-operative external pituitary irradiation lowered the mean growth hormone (GH) level from 75 mU/l to less than 1 mU/l within 2 years. However, at the same time hyperprolactinaemia developed. These changes in the GH and prolactin levels were confirmed 3 and 4 years after irradiation. The cause of the hyperprolactinaemia was radiation-induced hypothalamic damage. Therefore it is suggested that similar damage may occur in patients receiving external pituitary irradiation for 'prolactinomas' and that this mechanism may contribute to the persistent hyperprolactinaemia observed in such patients. (author)

  6. The effect of caffeine on radiation-induced division delay

    International Nuclear Information System (INIS)

    Snyder, M.H.; Kimler, B.F.; Leeper, D.B.

    1977-01-01

    Caffeine (100 μg/ml) was added to monolayer cultures of Chinese hamster ovary cells coincident with 60 Co γ-irradiation (75 to 300 rad). The results indicated that caffeine (at concentrations that did not perturb cell-cycle progression as monitored by the mitotic selection technique) exerted a protective effect against radiation-induced division delay. This protection consisted of an increase in the number of cells that were refractory to the radiation insult, as well as a decrease in the average time that non-refractory cells were delayed before they recovered their ability to progress through the cell cycle. (U.K.)

  7. Tissue culture regeneration and radiation induced mutagenesis in banana

    International Nuclear Information System (INIS)

    Kulkarni, V.M.; Ganapathi, T.R.

    2009-01-01

    Radiation induced mutagenesis is an important tool for banana genetic improvement. At BARC, protocols for shoo-tip multiplication of commercial banana varieties have been developed and transferred to user agencies for commercial production. Excellent embryogenic cell suspensions were established in banana cvs. Rasthali and Rajeli, and were maintained at low temperatures for long-term storage. Normal plantlets were successfully regenerated from these cell suspensions. The cell suspensions and shoot-tip cultures were gamma-irradiated for mutagenesis. The mutagenized populations were field screened and a few interesting mutants have been isolated. The existence of genetic variation was confirmed using DNA markers. Further evaluation of these mutants is in progress. (author)

  8. Radiation-induced glycoside bond breaking in cellulose methyl ethers

    International Nuclear Information System (INIS)

    Petryaev, E.P.; Boltromeyuk, V.V.; Kovalenko, N.I.; Shadyro, O.I.

    1988-01-01

    Radiation-induced destruction of cellulose methyl ethers of different degree of esterification in aqueous solutions with and without acceptors: (N 2 O, O 2 , H 2 O + , Co(2), Cu(2)) is investigated. It is established that OH radicals make main contribution into radiolytic transformations of cellulose ethers in aqueous solutions. Reactions of radicals with free valency on carbon atoms containing secondary nonsubstituted hydroxyl groups lead also to glycoside bond breaking besides the reaction of β-fragmentation and hydrolysis of radicals with an unpaired electron localized near C 1 , C 4 , C 5 aroms

  9. Management of radiation-induced accelerated carotid atherosclerosis

    International Nuclear Information System (INIS)

    Loftus, C.M.; Biller, J.; Hart, M.N.; Cornell, S.H.; Hiratzka, L.F.

    1987-01-01

    Patients with long survival following cervical irradiation are at risk for accelerated carotid atherosclerosis. The neurologic presentation in these patients mimics naturally occurring atheromatous disease, but patients often present at younger ages and with less concurrent coronary or systemic vascular disease. Hypercholesterolemia also contributes to this accelerated arteriosclerosis. Angiographic findings in this disorder include disproportionate involvement of the distal common carotid artery and unusually long carotid lesions. Pathologic findings include destruction of the internal elastic lamina and replacement of the normal intima and media with fibrous tissue. This article describes two surgical patients with radiation-induced accelerated carotid atherosclerosis who typify the presentation and characteristics of this disease

  10. Effect of electrodes in the radiation induced conductivity for polymers

    International Nuclear Information System (INIS)

    Gregorio Filho, R.; Gross, B.

    1988-01-01

    Samples of PET with 23 μm thickness were exposed to continuous X-rays and the radiation-induced conductivity (RIC) as a function of time were measured, using electrodes of evaporated aluminum and gold. The results showed that the use of higher atomic number metal electrodes increase the received dose rate by sample, without almost modifying the time evolution of the RIC or its dependence with the applied electric field intensity. It is also showed that this increase is caused by the electrode placed in the face of the sample where the radiation strikes, as well as by the one placed in the oposite face. (author) [pt

  11. Radiation-induced attenuation in integrated optical materials

    International Nuclear Information System (INIS)

    Evans, B.D.

    1989-01-01

    This paper reports that three materials commonly employed in opto-electronic integrated circuits evaluated for radiation-induced optical attenuation in the range 300 nm to 3000 nm. These include optically clear epoxy and crystalline lithium niobate after Co-60 exposure and crystalline tellurium dioxide after mixed gamma/fast-neutron exposure. In all these materials, however, induced loss was restricted to shorter wavelengths; attenuation induced at the telecommunications windows near 850, 1300 and 1550 nm was <0.1 dB/cm

  12. Radiation-induced cationic curing of vinyl ethers

    International Nuclear Information System (INIS)

    Lapin, S.C.

    1992-01-01

    Recently there has been an increasing interest in nonacrylate radiation-curable coatings. Vinyl ethers are particularly reactive under cationic polymerization reaction conditions. The high efficiency of the photoacid initiators combined with the high reactivity of vinyl ether monomers makes this a potentially very useful system. This chapter discusses the preparation of vinyl ethers, introduces vinyl ether-functional monomers and oligomers, describes radiation-induced cationic polymerization of vinyl ethers, and discusses various coating systems. Throughout the chapter, an emphasis is placed on radiation-curable coating applications. 64 refs., 5 figs., 11 tabs

  13. Immobilization of yeast cells by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Fujimura, T.; Kaetsu, I.

    1982-01-01

    Radiation-induced polymerization method was applied to the immobilization of yeast cells. The effects of irradiation, cooling and monomer, which are neccessary for polymerization, were recovered completely by subsequent aerobical incubation of yeast cells. The ethanol productive in immobilized yeast cells increased with the increase of aerobical incubation period. The growth of yeast cells in immobilized yeast cells was indicated. The maximum ethanol productivity in immobilized yeast cell system was around three times as much as that in free yeast cell system. (orig.)

  14. Radiation-induced life-shortening and premature aging

    International Nuclear Information System (INIS)

    Walburg, H.E. Jr.

    1975-01-01

    Data from a number of studies on irradiated laboratory animals showed that almost none of the characteristic lesions associated with senescence that were studied adequately reflects a radiation effect analogous to premature aging. In fact, most of the age-related changes showed no effect of radiation at all, and many of those that did (for example, graying of hair, sterility, cataract formation) did not appear to be due to similar mechanisms. It is concluded that, in the light of more recent information, the hypothesis of radiation-induced premature aging requires reassessment. (80 references) (CH)

  15. Delayed radiation-induced necrosis of the brain stem

    International Nuclear Information System (INIS)

    Yukawa, Osamu; Kodama, Yasunori; Kyoda, Jun; Yuki, Kiyoshi; Taniguchi, Eiji; Katayama, Shoichi; Hiroi, Tadashi; Uozumi, Toru.

    1993-01-01

    A 46-year-old man had surgery for a mixed glioma of the frontotemporal lobe. Postoperatively he received 50 Gy of irradiation. Sixteen months later he developed left hemiparesis and left facial palsy. MRI revealed lesion brain stem and basal ganglia. Despite chemotherapy and an additional 50 Gy dose, the patient deteriorated. Autopsy revealed a wide spread radiation-induced necrosis in the right cerebral hemisphere, midbrain and pons. In radiation therapy, great care must be taken to protect the normal brain tissue. (author)

  16. Facial reconstruction for radiation-induced skin cancer

    International Nuclear Information System (INIS)

    Panje, W.R.; Dobleman, T.J.

    1990-01-01

    Radiation-induced skin cancers can be difficult to diagnose and treat. Typically, a patient who has received orthovoltage radiotherapy for disorders such as acne, eczema, tinea capitis, skin tuberculosis, and skin cancer can expect that aggressive skin cancers and chronic radiodermatitis may develop subsequently. Cryptic facial cancers can lead to metastases and death. Prophylactic widefield excision of previously irradiated facial skin that has been subject to multiple recurrent skin cancers is suggested as a method of deterring future cutaneous malignancy and metastases. The use of tissue expanders and full-thickness skin grafts offers an expedient and successful method of subsequent reconstruction

  17. Radiation-induced invagination of the nuclear envelope

    International Nuclear Information System (INIS)

    Szekely, J.G.; Copps, T.P.; Morash, B.D.

    1980-01-01

    Using electron microscopy, we have measured radiation-induced invagination of the nuclear envelope of Chinese hamster V-79 and mouse L cells to produce a quantifiable radiation endpoint on a membrane system. In the dose ranges measured (800 to 3000 rad in L cells and 1270 to 5700 rad in V-79 cells), the amount of invagination increased with dose and continued to develop in intact cells for up to 72 hr after the original population was irradiated. Small vacuoles, which sometimes appeared in the nuclei of L cells, were also more numerous in irradiated cells and increased with dose and incubation time in a similar fashion to invagination development

  18. Weak-beam electron microscopy of radiation-induced segregation

    International Nuclear Information System (INIS)

    Saka, H.

    1983-01-01

    The segregation of solute atoms to dislocations during irradiation by 1 MeV electrons in a HVEM was studied by measuring the dissociation width of extended dislocations in Cu-5.1 at.%Si, Cu-5.3 at.%Ge, Ag-9.4 at.% In and Ag-9.6 at.%Al alloys. 'Weak-beam' electron microscopy was used. In Cu-Si (oversized solute), Cu-Ge (oversize) and Ag-Al (undersize), solute enrichment was observed near dislocations, while in Ag-In (oversize) solute depletion was observed. The results are discussed in terms of current mechanisms for radiation-induced segregation. (author)

  19. Use of radiation-induced polymers in cement slurries

    International Nuclear Information System (INIS)

    Knight, B.L.; Rhudy, J.S.; Gogarty, W.B.

    1976-01-01

    Water loss from cement slurries is reduced by incorporating within a cement slurry a polymer obtained as a product of radiation-induced polymerization of acrylamide and/or methacrylamide and acrylic acid, methacrylic acid, and/or alkali metal salts thereof. The polymerization is preferably carried out in 10-60 percent aqueous monomer solution with gamma radiation. The aqueous monomer solution preferably contains 25-99 percent acrylamide and 75-1 percent sodium acrylate. The polymer can be present in concentration of about 0.001 to about 3.0 weight percent, based on the aqueous phase of the slurry

  20. Radiation-induced O-glycoside bond scission in carbohydrates

    International Nuclear Information System (INIS)

    Kisel', R.M.

    2005-01-01

    Regularities in formation of products resulting from O-glycoside bond cleavage on radiolysis of aqueous solutions of (-methyl-D-glucopyranoside (I), 3-O-methylglucopyranose (II), maltose and lactose were studied. Oxygen and quinones were shown to inhibit radiation-induced homolytic destruction processes taking place in glycosides. The data obtained in this study enabled the authors to demonstrate an important role played by fragmentation reaction of C-2 radicals generated from the starting substances in formation of final radiolysis products. (authors)

  1. 'Like new': plastic wastes regeneration by radiation induced grafting

    International Nuclear Information System (INIS)

    Laizier, J.; Gaussens, G.; Lemaire, F.

    1978-01-01

    The reclaiming and the recycling of plastic wastes is made especially difficult when those wastes are a mixture of various plastics; this is due to the incompatibility of the polymers. The radiation induced grafting allows to overcome this incompatibility. Results are given which shows that, for various mixtures of reclaimed polyethylene, PVC and polystyrene, an improvement of the properties of the processed blends is obtained by grafting the mixtures of wastes by a suitable polymer; the obtained properties of those regenerated plastic blends are enough attractive from the technical point of view to open a market to those products with a reasonable economical value [fr

  2. Alteration of the digestive motility linked with radiation-induced inflammatory processes in rats

    International Nuclear Information System (INIS)

    Picard, C.

    2000-12-01

    Exposure to ionizing radiation, whether accidental or for medical reasons, may lead to gastro-intestinal injury, characterized by nausea, vomiting, diarrhea and abdominal cramps. The aetiology of radiation-induced diarrhea remains to date unclear. In this study, we have investigated the acute effects of a 10 Gy abdominal irradiation on rat digestive functions. The objective of the first study was to evaluate the role of sensory afferent neurons, capsaicin-sensitive, on morphological changes and the inflammatory response following exposure. Three days after irradiation, we observed an inflammatory response characterized by neutrophils infiltration and mast cells de-granulation. No effect of capsaicin pre-treatment was seen on these parameters. However, neutrophils infiltration was increased as early as one day after irradiation in capsaicin-treated rats. No difference in severity of diarrhea was observed after denervation nor in morphological changes. These data demonstrate that abdominal irradiation results in diarrhea concomitant with an inflammatory response, and that sensory innervation does not play a major protective role. The objective of the rest of the work was in the first instance to characterize radiation-induced alterations of intestinal and colonic motility leading to diarrhea and secondly to evaluate the role of serotonin in such disorders. Perturbations in intestinal (MMC) and colonic (LSB) motor profiles were observed from the first day onwards. Migrating motor complexes (MMC) were completely disrupted at three days at the same time as the onset of diarrhea. In addition to inhibition of LSB, colonic fluid absorptive capacity was decreased and serotonin colonic tissue levels were increased three days after irradiation. Radiation-induced diarrhea was reduced by treatment with an antagonist of 5-HT 3 receptors, granisetron, as were alterations of colonic motility and serotonin tissue levels. However, this treatment did not significantly ameliorate

  3. Radiation-induced oesophagitis in lung cancer patients. Is susceptibility for neutropenia a risk factor?

    Energy Technology Data Exchange (ETDEWEB)

    Ruysscher, D. de [MAASTRO Clinic, Maastricht (Netherlands). Dept. of Radiation Oncology; Meerbeeck, J. van [Ghent Univ. Hospital (Belgium). Dept. of Respiratory Medicine; Vandecasteele, K. [Ghent Univ. Hospital (BE). Dept. of Radiation Oncology] (and others)

    2012-07-15

    Background: Radiation-induced oesophagitis is a major side effect of concurrent chemotherapy and radiotherapy. A strong association between neutropenia and oesophagitis was previously shown, but external validation and further elucidation of the possible mechanisms are lacking. Methods and patients: A total of 119 patients were included at two institutions. The concurrent group comprised 34 SCLC patients treated with concurrent carboplatin and etoposide, and concurrent chest irradiation, and 36 NSCLC patients with concurrent cisplatin and etoposide, and concurrent radiotherapy, while the sequential group comprised 49 NSCLC patients received sequential cisplatin and gemcitabine, and radiotherapy. Results: Severe neutropenia was very frequent during concurrent chemoradiation (grade: 4 41.4%) and during induction chemotherapy in sequentially treated patients (grade 4: 30.6%), but not during radiotherapy (only 4% grade 1). In the concurrent group, the odds ratios of grade 3 oesophagitis vs. neutropenia were the following: grade 2 vs. grade 0/1: 5.60 (95% CI 1.55-20.26), p = 0.009; grade 3 vs. grade 0/1: 10.40 (95% CI 3.19-33.95); p = 0.0001; grade 4 vs. grade 0/1: 12.60 (95% CI 4.36-36.43); p < 0.00001. There was no correlation between the occurrence of neutropenia during induction chemotherapy and acute oesophagitis during or after radiotherapy alone. In the univariate analysis, total radiation dose (p < 0.001), overall treatment time of radiotherapy (p < 0.001), mean oesophageal dose (p = 0.038) and neutropenia (p < 0.001) were significantly associated with the development of oesophagitis. In a multivariate analysis, only neutropenia remained significant (p = 0.023). Conclusion: We confirm that neutropenia is independently correlated with oesophagitis in concurrent chemoradiation, but that the susceptibility for chemotherapy-induced neutropenia is not associated with radiation-induced oesophagitis. Further studies focusing on the underlying mechanisms are thus

  4. Effect of Sucralfate on Radiation-induced Esophageal Changes in Rat

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Ki Mun; Chai, Gyu Young [Gyeongsang National Univ., Jinju (Korea, Republic of); Yoon, Sei Chul [The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2001-12-15

    The study was designed to evaluate the response of sucralfate against the esophageal damage of rat by irradiation. Sixty Sprague-Dawley rats weighing 200-250 gm were divided into six groups including only sucralfate group, the group of 10 Gy or 20 Gy radiation alone, the groups of 10 Gy or 20 Gy radiation-sucralfate combination, and control. Each group was sacrificed at 3, 7, 14 and 28 days after irradiation. For evaluation of the radiation-induced esophageal lesions, there were examined the change of body weight, barium-esophagogram and histopathologic findings. Mean body weight gain was decreased in the groups with 10 Gy or 20 Gy radiation alone and 10 Gy or 20 Gy radiation-sucralfate combination as comparing with control (p=0.03, p=0.02, p=0.04, p=0.02), but there was no difference between the groups of 10 Gy or 20 Gy radiation alone and the groups of 10 Gy or 20 Gy radiation-sucralfate combination. In the 20 Gy and 20 Gy radiation alone groups, barium esophagograms showed diffuse narrowing and stiffness through the entire esophagus from 7 days after irradiation, but there was similar pattern of esophagograms between the groups of 10 Gy radiation-sucralfate combination and the control. Histopathologic lesion scores of 10 Gy and 20 Gy radiation groups were significantly higher than the control (p=0.03, p=0.008). In the 10 Gy radiation group, there were significantly higher lesion scores ar 3 and 7 days after irradiation as comparing with those in the group of radiation-sucralfate combination (p=0.04, p=0.03). These results suggest that sucralfate might be played as a role of protection from acute radiation-induced esophagitis within the limit of tolerable radiation doses.

  5. Effect of Sucralfate on Radiation-induced Esophageal Changes in Rat

    International Nuclear Information System (INIS)

    Kang, Ki Mun; Chai, Gyu Young; Yoon, Sei Chul

    2001-01-01

    The study was designed to evaluate the response of sucralfate against the esophageal damage of rat by irradiation. Sixty Sprague-Dawley rats weighing 200-250 gm were divided into six groups including only sucralfate group, the group of 10 Gy or 20 Gy radiation alone, the groups of 10 Gy or 20 Gy radiation-sucralfate combination, and control. Each group was sacrificed at 3, 7, 14 and 28 days after irradiation. For evaluation of the radiation-induced esophageal lesions, there were examined the change of body weight, barium-esophagogram and histopathologic findings. Mean body weight gain was decreased in the groups with 10 Gy or 20 Gy radiation alone and 10 Gy or 20 Gy radiation-sucralfate combination as comparing with control (p=0.03, p=0.02, p=0.04, p=0.02), but there was no difference between the groups of 10 Gy or 20 Gy radiation alone and the groups of 10 Gy or 20 Gy radiation-sucralfate combination. In the 20 Gy and 20 Gy radiation alone groups, barium esophagograms showed diffuse narrowing and stiffness through the entire esophagus from 7 days after irradiation, but there was similar pattern of esophagograms between the groups of 10 Gy radiation-sucralfate combination and the control. Histopathologic lesion scores of 10 Gy and 20 Gy radiation groups were significantly higher than the control (p=0.03, p=0.008). In the 10 Gy radiation group, there were significantly higher lesion scores ar 3 and 7 days after irradiation as comparing with those in the group of radiation-sucralfate combination (p=0.04, p=0.03). These results suggest that sucralfate might be played as a role of protection from acute radiation-induced esophagitis within the limit of tolerable radiation doses

  6. Bone marrow stromal cell transplantation mitigates radiation-induced gastrointestinal syndrome in mice.

    Directory of Open Access Journals (Sweden)

    Subhrajit Saha

    Full Text Available Nuclear accidents and terrorism presents a serious threat for mass casualty. While bone-marrow transplantation might mitigate hematopoietic syndrome, currently there are no approved medical countermeasures to alleviate radiation-induced gastrointestinal syndrome (RIGS, resulting from direct cytocidal effects on intestinal stem cells (ISC and crypt stromal cells. We examined whether bone marrow-derived adherent stromal cell transplantation (BMSCT could restitute irradiated intestinal stem cells niche and mitigate radiation-induced gastrointestinal syndrome.Autologous bone marrow was cultured in mesenchymal basal medium and adherent cells were harvested for transplantation to C57Bl6 mice, 24 and 72 hours after lethal whole body irradiation (10.4 Gy or abdominal irradiation (16-20 Gy in a single fraction. Mesenchymal, endothelial and myeloid population were characterized by flow cytometry. Intestinal crypt regeneration and absorptive function was assessed by histopathology and xylose absorption assay, respectively. In contrast to 100% mortality in irradiated controls, BMSCT mitigated RIGS and rescued mice from radiation lethality after 18 Gy of abdominal irradiation or 10.4 Gy whole body irradiation with 100% survival (p<0.0007 and p<0.0009 respectively beyond 25 days. Transplantation of enriched myeloid and non-myeloid fractions failed to improve survival. BMASCT induced ISC regeneration, restitution of the ISC niche and xylose absorption. Serum levels of intestinal radioprotective factors, such as, R-Spondin1, KGF, PDGF and FGF2, and anti-inflammatory cytokines were elevated, while inflammatory cytokines were down regulated.Mitigation of lethal intestinal injury, following high doses of irradiation, can be achieved by intravenous transplantation of marrow-derived stromal cells, including mesenchymal, endothelial and macrophage cell population. BMASCT increases blood levels of intestinal growth factors and induces regeneration of the irradiated

  7. Radiation-induced oesophagitis in lung cancer patients. Is susceptibility for neutropenia a risk factor?

    International Nuclear Information System (INIS)

    Ruysscher, D. de; Meerbeeck, J. van; Vandecasteele, K.

    2012-01-01

    Background: Radiation-induced oesophagitis is a major side effect of concurrent chemotherapy and radiotherapy. A strong association between neutropenia and oesophagitis was previously shown, but external validation and further elucidation of the possible mechanisms are lacking. Methods and patients: A total of 119 patients were included at two institutions. The concurrent group comprised 34 SCLC patients treated with concurrent carboplatin and etoposide, and concurrent chest irradiation, and 36 NSCLC patients with concurrent cisplatin and etoposide, and concurrent radiotherapy, while the sequential group comprised 49 NSCLC patients received sequential cisplatin and gemcitabine, and radiotherapy. Results: Severe neutropenia was very frequent during concurrent chemoradiation (grade: 4 41.4%) and during induction chemotherapy in sequentially treated patients (grade 4: 30.6%), but not during radiotherapy (only 4% grade 1). In the concurrent group, the odds ratios of grade 3 oesophagitis vs. neutropenia were the following: grade 2 vs. grade 0/1: 5.60 (95% CI 1.55-20.26), p = 0.009; grade 3 vs. grade 0/1: 10.40 (95% CI 3.19-33.95); p = 0.0001; grade 4 vs. grade 0/1: 12.60 (95% CI 4.36-36.43); p < 0.00001. There was no correlation between the occurrence of neutropenia during induction chemotherapy and acute oesophagitis during or after radiotherapy alone. In the univariate analysis, total radiation dose (p < 0.001), overall treatment time of radiotherapy (p < 0.001), mean oesophageal dose (p = 0.038) and neutropenia (p < 0.001) were significantly associated with the development of oesophagitis. In a multivariate analysis, only neutropenia remained significant (p = 0.023). Conclusion: We confirm that neutropenia is independently correlated with oesophagitis in concurrent chemoradiation, but that the susceptibility for chemotherapy-induced neutropenia is not associated with radiation-induced oesophagitis. Further studies focusing on the underlying mechanisms are thus

  8. Sestrin2 protects the myocardium against radiation-induced damage

    International Nuclear Information System (INIS)

    Zeng, Yue-Can; Chi, Feng; Xing, Rui; Gao, Song; Chen, Jia-Jia; Duan, Qiong-Yu; Sun, Yu-Nan; Niu, Nan; Tang, Mei-Yue; Wu, Rong; Zeng, Jing; Wang, Hong-Mei

    2016-01-01

    The purpose of this study was to investigate the role of Sestrin2 in response to radiation-induced injury to the heart and on the cardiomyopathy development in the mouse. Mice with genetic deletion of the Sestrin2 (Sestrin2 knockout mice [Sestrin2 KO]) and treatment with irradiation (22 or 15 Gy) were used as independent approaches to determine the role of Sestrin2. Echocardiography (before and after isoproterenol challenge) and left ventricular (LV) catheterization were performed to evaluate changes in LV dimensions and function. Masson's trichrome was used to assess myocardial fibrosis. Immunohistochemistry and Western blot were used to detect the capillary density. After 22 or 15 Gy irradiation, the LV ejection fraction (EF) was impaired in wt mice at 1 week and 4 months after irradiation when compared with sham irradiation. Compared to wt mice, Sestrin2 KO mice had significant reduction in reduced LVEF at 1 week and 4 months after irradiation. A significant increase in LV end-diastolic pressure and myocardial fibrosis and a significant decrease in capillary density were observed in irradiation-wt mice, as well as in irradiation-Sestrin2 KO mice. Sestrin2 involved in the regulation of cardiomyopathy (such as myocardial fibrosis) after irradiation. Overexpression of Sestrin2 might be useful in limiting radiation-induced myocardial injury. (orig.)

  9. Radiation-induced segregation in Cu-Au alloys

    International Nuclear Information System (INIS)

    Hashimoto, T.; Rehn, L.E.; Okamoto, P.R.

    1987-01-01

    Radiation-induced segregation in a Cu-lat.% Au alloy was investigated using in-situ Rutherford backscattering spectrometry. Irradiation with 1.8-MeV helium produced nonequilibrium gold atom depletion in the near surface region. The amount of segregation was measured as a function of dose, dose rate, and temperature. Segregation was observed in the temperature range between about 300 and 500 0 C. For a calculated dose rate of 3.9 x 10/sup -5/ dpa/s, the radiation-induced segregation rate peaked near 400 0 C. Theoretical analysis based on the Johnson-Lam model predicted that the amount of segregation would be directly proportional to dose at the early stage of irradiation, would deviate from linearity with a continuously decreasing slope of intermediate doses, and finally approach a constant value after high doses. The analysis also predicted that the segregation rate would vary as the - 1/4th power of the dose rate at constant dose in the low temperature region. These predictions were all verified experimentally. A procedure for extracting relative defect production efficiencies from similar measurements is discussed

  10. Radiation-induced electron migration in nucleic acids

    International Nuclear Information System (INIS)

    Fuciarelli, A.F.; Sisk, E.C.; Miller, J.H.; Zimbrick, J.D.

    1994-01-01

    Radiation-induced electron migration along DNA is a mechanism by which randomly produced stochastic energy deposition events can lead to non-random types of damage along DNA manifested distal to the sites of the initial energy deposition. Radiation-induced electron migration in nucleic acids has been examined using oligonucleotides containing 5-bromouracil (5-BrU). Interaction of 5-BrU with solvated electrons results in release of bromide ions and formation of uracil-5-yl radicals. Monitoring either bromide ion release or uracil formation provides an opportunity to study electron migration processes in model nucleic acid systems. Using this approach we have discovered that electron migration along oligonucleotides is significantly influenced by the base sequence and strandedness. Migration along 7 base pairs in oligonucleotides containing guanine bases was observed for oligonucleotides irradiated in solution, which compares with mean migration distances of 6-10 bp for Escherichia coli DNA irradiated in solution and 5.5 bp for E. coli DNA irradiated in cells. Evidence also suggests that electron migration can occur preferentially in the 5' to 3' direction along a double-stranded oligonucleotide containing a region of purine bases adjacent to the 5-BrU moiety. Our continued efforts will provide information regarding the contribution of electron transfer along DNA to formation of locally multiply damaged sites created in DNA by exposure to ionizing radiation. (Author)

  11. Improvement of boiling heat transfer by radiation induced boiling enhancement

    International Nuclear Information System (INIS)

    Imai, Yasuyuki; Okamoto, Koji; Madarame, Haruki; Takamasa, Tomoji

    2003-01-01

    For nuclear reactor systems, the critical heat flux (CHF) data is very important because it limits reactor efficiency. Improvement of CHF requires that the cooling liquid can contact the heating surface, or a high-wettability, highly hydrophilic heating surface, even if a vapor bubble layer is generated on the surface. In our previous study, we confirmed that the surface wettability changed significantly or that highly hydrophilic conditions were achieved, after irradiation of 60 Co gamma ray, by the Radiation Induced Surface Activation (RISA) phenomenon. To delineate the effect of RISA on boiling phenomena, surface wettability in a high-temperature environment and critical heat flux (CHF) of metal oxides irradiated by gamma rays were investigated. A CHF experiment in the pool boiling condition was carried out under atmospheric pressure. The heating test section made of titanium was 0.2 mm in thickness, 3 mm in height, and 60 mm in length. Oxidation of the surface was carried out by plasma jetting for 40 seconds. The test section was irradiated by 60 Co gamma ray with predetermined radiation intensity and period. The CHF of oxidized titanium was improved up to 100 percent after 800 kGy 60 Co gamma ray irradiation. We call this effect Radiation Induced Boiling Enhancement (RIBE). Before we conducted the CHF experiment, contact angles of the test pieces were measured to show the relationship between wettability and CHF. The CHF in the present experiment increases will surface wettability in the same manner as shown by Liaw and Dhir's results. (author)

  12. Ionizing radiation induced conductivity in Mylar (PET) and Kapton (Polyimide)

    International Nuclear Information System (INIS)

    Gregorio Filho, R.

    1986-01-01

    The extensive results of measurements of the prompt and delayed radiation-induced conductivity of samples of PET and Kapton are presented. Experimental parameters, such as the effective energy of the radiation, the exposure rate, the total dose, the value of the applied electric field, the nature of the electrodes, and the ambiental conditions were changed within wide limits. We also report measurement of thermally stimulated currents for non-irradiated and for irradiated samples which allowed us to investigate the trap-structure of the materials. Measurements of photo-Compton currents with different electrode materials and sample thicknesses gave information about the relation between the nature of the electrodes and the amplitudes of the currents. Based on the generalized rate theory of radiation-induced conduction we developed a theoretical model which includes the effect of the applied electric field on the carrier generation yield (geminate recombination, Onsager effect). Comparison of experimental and theoretical curves allowed us to determine the values of the main conduction parameters, such as carrier mobility, recombination coefficient, trap densities, for the materials under investigation. (Author) [pt

  13. Radiation-induced mucositis pain in laryngeal cancer

    International Nuclear Information System (INIS)

    Takahashi, Atsuhito; Shoji, Kazuhiko; Iki, Takehiro; Mizuta, Masanobu; Matsubara, Mami

    2009-01-01

    Radiation therapy in those with head and neck malignancies often triggers painful mucositis poorly controlled by nonsteroidal antiinflammatory drugs (NSAIDs). To better understand how radiation-induced pain develops over time, we studied the numerical rating scale (NRS 0-5) pain scores from 32 persons undergoing radiation therapy of 60-72 Gy for newly diagnosed laryngeal cancer. The degree of mucositis was evaluated using Common Terminology Criteria for Adverse Events version3.0 (CTCAE v3.0). We divided the 32 into a conventional fractionation (CF) group of 14 and a hyperfractionation (HF) group of 18, and further divided laryngeal cancer into a small-field group of 23 and a large-field group of 9. The mucositis pain course was similar in CF and HF, but mucositis pain was severer in the HF group, which also required more NSAIDs. Those in the large-field group had severer pain and mucositis and required more NSAIDs than those in the small-field group. We therefore concluded that small/large-field radiation therapy, rather fractionation type, was related to the incidence of radiation-induced mucositis pain. (author)

  14. Protection from ionizing radiation induced damages by phytoceuticals and nutraceuticals

    International Nuclear Information System (INIS)

    Nair, C.K.K.

    2012-01-01

    Exposure of living systems to ionizing radiation cause a variety of damages to DNA and membranes due to generation of free radicals and reactive oxygen species. The radiation induced lesions in the cellular DNA are mainly strand breaks, damage to sugar moiety, alterations and elimination of bases, cross links of the intra and inter strand type and cross links to proteins while peroxidation of the lipids and oxidation of proteins constitute the major lesions in the membranes. The radioprotectors elicit their action by various mechanisms such as i) by suppressing the formation of reactive species, ii) detoxification of radiation induced species, iii) target stabilization and iv) enhancing the repair and recovery processes. The radioprotective compounds are of importance in medical, industrial, environmental, military and space science applications. Radiation protection might offer a tactical advantage on the battlefield in the event of a nuclear warfare. Radioprotectors might reduce the cancer risk to populations exposed to radiations directly or indirectly through industrial and military applications. The antioxidant and radioprotective properties a few of these agents under in vitro and in vivo conditions in animal models will be discussed

  15. Sestrin2 protects the myocardium against radiation-induced damage

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Yue-Can; Chi, Feng; Xing, Rui; Gao, Song; Chen, Jia-Jia; Duan, Qiong-Yu; Sun, Yu-Nan; Niu, Nan; Tang, Mei-Yue; Wu, Rong [Shengjing Hospital of China Medical University, Department of Medical Oncology, Cancer Center, Shenyang (China); Zeng, Jing [University of Washington School of Medicine, Department of Radiation Oncology, Seattle, WA (United States); Wang, Hong-Mei [Nanfang Hospital of Southern Medical University, Department of Radiation Oncology, Guangzhou (China)

    2016-05-15

    The purpose of this study was to investigate the role of Sestrin2 in response to radiation-induced injury to the heart and on the cardiomyopathy development in the mouse. Mice with genetic deletion of the Sestrin2 (Sestrin2 knockout mice [Sestrin2 KO]) and treatment with irradiation (22 or 15 Gy) were used as independent approaches to determine the role of Sestrin2. Echocardiography (before and after isoproterenol challenge) and left ventricular (LV) catheterization were performed to evaluate changes in LV dimensions and function. Masson's trichrome was used to assess myocardial fibrosis. Immunohistochemistry and Western blot were used to detect the capillary density. After 22 or 15 Gy irradiation, the LV ejection fraction (EF) was impaired in wt mice at 1 week and 4 months after irradiation when compared with sham irradiation. Compared to wt mice, Sestrin2 KO mice had significant reduction in reduced LVEF at 1 week and 4 months after irradiation. A significant increase in LV end-diastolic pressure and myocardial fibrosis and a significant decrease in capillary density were observed in irradiation-wt mice, as well as in irradiation-Sestrin2 KO mice. Sestrin2 involved in the regulation of cardiomyopathy (such as myocardial fibrosis) after irradiation. Overexpression of Sestrin2 might be useful in limiting radiation-induced myocardial injury. (orig.)

  16. Radiation-induced segregation in binary and ternary alloys

    International Nuclear Information System (INIS)

    Okamoto, P.R.; Rehn, L.E.

    1979-01-01

    A review is given of our current knowledge of radiation-induced segregation of major and minor elements in simple binary and ternary alloys as derived from experimental techniques such as Auger electron spectroscopy, secondary-ion mass spectroscopy, ion-backscattering, infrared emissivity measurements and transmission electron microscopy. Measurements of the temperature, dose and dose-rate dependences as well as of the effects of such materials variables as solute solubility, solute misfit and initial solute concentration has proved particularly valuable in understanding the mechanisms of segregation. The interpretation of these data in terms of current theoretical models which link solute segregation behavior to defect-solute binding interactions and/or to the relative diffusion rates of solute and solvent atoms the interstitial and vacancy migration mechanisms has, in general, been fairly successful and has provided considerable insight into the highly interrelated phenomena of solute-defect trapping, solute segregation, phase stability and void swelling. Specific examples in selected fcc, bcc and hcp alloy systems are discussed with particular emphasis given to the effects of radiation-induced segregation on the phase stability of single-phase and two-phase binary alloys and simple Fe-Cr-Ni alloys. (Auth.)

  17. Neurolysis and myocutaneous flap for radiation induced brachial plexus neuropathy

    International Nuclear Information System (INIS)

    Hirachi, Kazuhiko; Minami, Akio; Kato, Hiroyuki; Nishio, Yasuhiko; Ohnishi, Nobuki

    1998-01-01

    Surgical treatment for radiation induced brachial plexus neuropathy is difficult. We followed 9 patients of radiation induced brachial plexus neuropathy who were surgically treated with neurolysis and myocutaneous flap coverage. Their ages ranged from 29 to 72 years old. Their diagnoses were breast cancer in 6 patients, lingual cancer in 1, thyroid cancer in 1 and malignant lymphoma in 1. Total dose of radiation ranged from 44 to 240 Gy. Interval from radiation therapy to our surgery ranged from 1 to 18 years (mean 6.7 years). Chief complaints were dysesthesia in 9 patients, motor weakness in 7 patients and dullach in scar formation of radiated skin in 7 patients. Preoperative neural functions were slight palsy in 1, moderate palsy in 5 and complete palsy in 3. In surgical treatment, neurolysis of the brachial plexus was done and it was covered by latissimus dorsi myocutaneous flap. We evaluated about dysesthesia and motor recovery after treatment for neuropathy. Follow up periods ranged from 1 to 11 years (average in 5 years). Dysesthesia improved in 6 patients and got worse in 3 patients. Motor weakness recovered in only 2 patients and got worse in 7 patients. From our results, intolerable dysesthesia which was first complaint of these patients improved. But motor function had not recovered. Our treatment was thought to be effective for extraneural factor like an compression neuropathy by scar formation and poor vascularity. But it was not effective for intraneural damage by radiation therapy. (author)

  18. Treatment of a radiation-induced brachial plexopathy

    International Nuclear Information System (INIS)

    Tanaka, Ichirou; Harashina, Takao; Inoue, Takeo; Ueda, Kouichi; Hatoko, Mituo; Shidara, Yukinobu; Ito, Yoshiyasu.

    1990-01-01

    A radiation-induced brachial plexopathy after a mastectomy causes severe pain and numbness, as well as motor and sensory disorders. Severe pain is often resistant to analgesic blocks, and in most instances, the effect of neurolysis is only temporary. We have treated two such patients with microsurgical neurolysis and then have covered the nerve by transferred muscles. In one case, the exposed brachial plexus was covered with a pedicled latissimus dorsi muscle flap, and in the other, with a free rectus abdominis muscle flap. Pain and numbness were markedly improved in these two patients soon after the surgery, and the improvement in the sensory function also was relatively satisfactory. In one case, the motor function also improved. These patients have had no recurrence of pain or numbness for 4 years and 2 months and 4 years and 7 months after surgery, respectively. Further, their sensory and motor disorders did not advance. Surgical indications for a radiation-induced brachial plexopathy remain controversial, since the operation does not always ensure a marked improvement in the sensory and motor functions. Further, the operation is ineffective for patients with advanced nerve degeneration. Taking these factors into consideration, the preoperative predication of beneficial effects from this surgery is difficult. Despite our limited experience, however, our surgical method has been thought to be effective because it achieves a marked improvement in the numbness and pain experienced in the arms, which are usually the patients' chief complaints. (author)

  19. Improvement of boiling heat transfer by radiation induced boiling enhancement

    International Nuclear Information System (INIS)

    Imai, Y.; Okamoto, K.; Madarame, H.; Takamasa, T.

    2003-01-01

    For nuclear reactor systems, the Critical Heat Flux (CHF) data is very important because it limits reactor efficiency. Improvement of CHF requires that the cooling liquid can contact the heating surface, or a high-wettability, highly hydrophilic heating surface, even if a vapor bubble layer is generated on the surface. In our previous study, we confirmed that the surface wettability changed significantly or that highly hydrophilic conditions were achieved, after irradiation of 60Co gamma ray, by the Radiation Induced Surface Activation (RISA) phenomenon. To delineate the effect of RISA on boiling phenomena, surface wettability in a high-temperature environment and Critical Heat Flux (CHF) of metal oxides irradiated by gamma rays were investigated. A CHF experiment in the pool boiling condition was carried out under atmospheric pressure. The heating test section made of titanium was 0.2mm in thickness, 3mm in height, and 60mm in length. Oxidation of the surfaces was carried out by plasma jetting for 40 seconds. The test section was irradiated by 60Co gamma ray with predetermined radiation intensity and period. The CHF of oxidized titanium was improved up to 100 percent after 800kGy 60Co gamma ray irradiation. We call this effect Radiation Induced Boiling Enhancement (RIBE). Before we conducted the CHF experiment, contact angles of the test pieces were measured to show the relationship between wettability and CHF. The CHF in the present experiment increases with surface wettability in the same manner as shown by Liaw and Dhir's results

  20. Inhibition of radiation-induced polyuria by histamine receptor antagonists

    Energy Technology Data Exchange (ETDEWEB)

    Donlon, M.A.; Melia, J.A.; Helgeson, E.A.; Wolfe, W.W.

    1986-03-01

    In previous studies the authors have demonstrated that gamma radiation results in polyuria, which is preceded by polydypsia. This suggests that the increased thirst elicited by radiation causes increased urinary volume (UV). Histamine, which is released following radiation exposure, also elicits drinking by nonirradiated rats when administered exogenously. In this study the authors have investigated both the role of water deprivation and the effect of histamine receptor antagonists (HRA) on radiation-induced polyuria. Sprague-Dawley rats were housed individually in metabolic cages. Water was allowed ad libitum except in deprivation experiments where water was removed for 24 hr immediately following radiation. Cimetidine (CIM), an H2 HRA, and dexbromopheniramine (DXB), an H1 HRA, were administered i.p. (16 and 1 mg/kg, respectively) 30 min prior to irradiation (950 rads from a cobalt source). UV was determined at 24-hr intervals for 3 days preceding irradiation and 24 hr postirradiation. UV in DXB treated rats was significantly reduced 24 hr postirradiation (CON = 427 +/- 54%; DXB = 247 +/- 39% of preirradiated CON) compared to postirradiation control values. CIM did not affect postirradiation UV. These data suggest that radiation-induced polyuria is caused by polydypsia which is, in part, mediated by histamine induced by an H1 receptor.

  1. Inhibition of radiation-induced polyuria by histamine receptor antagonists

    International Nuclear Information System (INIS)

    Donlon, M.A.; Melia, J.A.; Helgeson, E.A.; Wolfe, W.W.

    1986-01-01

    In previous studies the authors have demonstrated that gamma radiation results in polyuria, which is preceded by polydypsia. This suggests that the increased thirst elicited by radiation causes increased urinary volume (UV). Histamine, which is released following radiation exposure, also elicits drinking by nonirradiated rats when administered exogenously. In this study the authors have investigated both the role of water deprivation and the effect of histamine receptor antagonists (HRA) on radiation-induced polyuria. Sprague-Dawley rats were housed individually in metabolic cages. Water was allowed ad libitum except in deprivation experiments where water was removed for 24 hr immediately following radiation. Cimetidine (CIM), an H2 HRA, and dexbromopheniramine (DXB), an H1 HRA, were administered i.p. (16 and 1 mg/kg, respectively) 30 min prior to irradiation (950 rads from a cobalt source). UV was determined at 24-hr intervals for 3 days preceding irradiation and 24 hr postirradiation. UV in DXB treated rats was significantly reduced 24 hr postirradiation (CON = 427 +/- 54%; DXB = 247 +/- 39% of preirradiated CON) compared to postirradiation control values. CIM did not affect postirradiation UV. These data suggest that radiation-induced polyuria is caused by polydypsia which is, in part, mediated by histamine induced by an H1 receptor

  2. Radiation-Induced Correlation between Molecules Nearby Metallic Antenna Array

    Directory of Open Access Journals (Sweden)

    Yoshiki Osaka

    2015-01-01

    Full Text Available We theoretically investigate optical absorption of molecules embedded nearby metallic antennas by using discrete dipole approximation method. It is found that the spectral peak of the absorption is shifted due to the radiation-induced correlation between the molecules. The most distinguishing feature of our work is to show that the shift is largely enhanced even when the individual molecules couple with localized surface plasmons near the different antennas. Specifically, we first consider the case that two sets of dimeric gold blocks with a spacing of a few nanometers are arranged and reveal that the intensity and spectral peak of the optical absorption strongly depend on the position of the molecules. In addition, when the dimeric blocks and the molecules are periodically arranged, the peak shift is found to increase up to ~1.2 meV (300 GHz. Because the radiation-induced correlation is essential for collective photon emission, our result implies the possibility of plasmon-assisted superfluorescence in designed antenna-molecule complex systems.

  3. Radiation-induced skin carcinomas of the head and neck

    International Nuclear Information System (INIS)

    Ron, E.; Modan, B.; Preston, D.; Alfandary, E.; Stovall, M.; Boice, J.D. Jr.

    1991-01-01

    Radiation exposures to the scalp during childhood for tinea capitis were associated with a fourfold increase in skin cancer, primarily basal cell carcinomas, and a threefold increase in benign skin tumors. Malignant melanoma, however, was not significantly elevated. Overall, 80 neoplasms were identified from an extensive search of the pathology logs of all major hospitals in Israel and computer linkage with the national cancer registry. Radiation dose to the scalp was computed for over 10,000 persons irradiated for ringworm (mean 7 Gy), and incidence rates were contrasted with those observed in 16,000 matched comparison subjects. The relative risk of radiogenic skin cancer did not differ significantly between men or women or by time since exposure; however, risk was greatest following exposures in early childhood. After adjusting for sex, ethnic origin, and attained age, the estimated excess relative risk was 0.7 per Gy and the average excess risk over the current follow-up was 0.31/10(4) PY-Gy. The risk per Gy of radiation-induced skin cancer was intermediate between the high risk found among whites and no risk found among blacks in a similar study conducted in New York City. This finding suggests the role that subsequent exposure to uv radiation likely plays in the expression of a potential radiation-induced skin malignancy

  4. [Biomarkers of radiation-induced DNA repair processes].

    Science.gov (United States)

    Vallard, Alexis; Rancoule, Chloé; Guy, Jean-Baptiste; Espenel, Sophie; Sauvaigo, Sylvie; Rodriguez-Lafrasse, Claire; Magné, Nicolas

    2017-11-01

    The identification of DNA repair biomarkers is of paramount importance. Indeed, it is the first step in the process of modulating radiosensitivity and radioresistance. Unlike tools of detection and measurement of DNA damage, DNA repair biomarkers highlight the variations of DNA damage responses, depending on the dose and the dose rate. The aim of the present review is to describe the main biomarkers of radiation-induced DNA repair. We will focus on double strand breaks (DSB), because of their major role in radiation-induced cell death. The most important DNA repair biomarkers are DNA damage signaling proteins, with ATM, DNA-PKcs, 53BP1 and γ-H2AX. They can be analyzed either using immunostaining, or using lived cell imaging. However, to date, these techniques are still time and money consuming. The development of "omics" technologies should lead the way to new (and usable in daily routine) DNA repair biomarkers. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  5. Radiation-induced recurrent intestinal pseudo-obstruction

    International Nuclear Information System (INIS)

    Conklin, J.L.; Anuras, S.

    1981-01-01

    The syndrome of intestinal pseudo-obstruction is a complex of signs and symptoms of intestinal obstruction without evidence of mechanical obstruction of the intestinal lumen. A patient with radiation-induced intestinal pseudoobstruction is described. The patient is a 74-year old woman with a history of chronic diarrhea, recurrent episodes of crampy abdominal pain, nausea and vomiting since receiving a 13,000 rad radiation dose to the pelvis in 1954. She has been hospitalized on many occasions for symptoms and signs of bowel obstruction. Upper gastrointestinal contrast roentgenograms with small bowel follow-through done during these episodes revealed multiple dilated loops of small bowel with no obstructing lesion. Barium enemas revealed no obstructing lesion. Each episode resolved with conservative therapy. Other secondary causes for intestinal pseudo-obstruction were ruled out in our patient. She gave no history of familial gastrointestinal disorders. Although postirradiation motility abnormalities have been demonstrated experimentally this is the first report of radiation induced intestinal pseudo-obstruction

  6. Radiation induced effects in the developing central nervous system

    International Nuclear Information System (INIS)

    Gisone, P.; Dubner, D.; Michelin, S.C.; Perez, M.R. Del

    1997-01-01

    The embryo and the human foetus are particularly sensitive to ionizing radiation and this sensitivity presents various qualitative and quantitative functional changes during intra-uterine development. Apart from radiation induced carcinogenesis, the most serious consequence of prenatal exposure in human beings is severe mental retardation. The principal data on radiation effects on human beings in the development of the central nervous system come form epidemiological studies carried out in individuals exposed in utero during the atomic explosion at Hiroshima and Nagasaki. These observations demonstrate the existence of a time of maximum radiosensitivity between the weeks 8 and 15 of the gestational period, a period in which the proliferation and neuronal migration takes place. Determination of the characteristics of dose-response relationship and the possible existence of a threshold dose of radiation effects on the development of the central nervous system is relevant to radiation protection against low dose radiation and the establishment of dose limits for occupational exposure and the public. Studies were conducted on the generation of nitrous-oxide and its relation with the production of active species of oxygen in brains of exposed rats in utero exposed to doses of up to 1 Gy during their maximum radiosensitivity. The possible role of the mechanism of radiation induced damage in the development of the central nervous system is discussed

  7. Radiation-induced grafting of styrene on polypropylene pellets

    International Nuclear Information System (INIS)

    Souza, Camila P.; Ferreira, Henrique P.; Parra, Duclerc F.; Lugao, Ademar B.

    2009-01-01

    The changes of radiation-induced in polypropylene (PP) pellets exposed to gamma irradiation in inert atmosphere were investigated in correlation with the applied doses (10 and 50 kGy). Also, results from the grafting of styrene onto PP pellets using simultaneous irradiation at the same doses are presented. The grafting reaction was carried out using toluene as solvent, under nitrogen atmosphere and at room temperature. The properties of the irradiated and grafted PP pellets were studied using Melt Flow Index, thermal analysis (TG and DSC), and ATR-IR. The degree of grafting (DOG) for the grafted pellets was gravimetrically determined. The results showed that radiation-induced graft polymerization on pellets were successfully obtained and the influence of dose irradiated did not change the thermal properties in spite of the increase in the MFI and consequently this increase in the viscosity results an decrease the molecular mass. The MFI for grafted pellets was not achievable because the high degree of viscosity of polymer, even arising the test temperature, the polymer was not flow enough. (author)

  8. Radiation-induced polymerization and radiation effect on polymers

    International Nuclear Information System (INIS)

    Seguchi, Tadao

    1977-12-01

    The processes of radiation-induced polymerization of monomers and also radiation effects on polymers have been studied by instrumental analyses of electron spin resonance (ESR), nuclear magnetic resonance (NMR) and electron microscopy. In radiation-induced polymerization, graft-copolymerization and absorbed state polymerization were taken up. For graft-copolymerization, monomers such as methylmethacrylate and butadiene were made to react with irradiated polyethylene, and behaviors of the initiating radicals and propagating radicals were followed under the reaction by ESR. For absorbed state polymerization, acrylonitrile/zeolite and methylmethacrylate/zeolite were chosen. Absorbed monomers were irradiated at 77 0 K and polymerized at room temperature. Active species and the concentrations were measured by ESR and the yields of polymer were observed by NMR. In radiation effect on polymers, polyvinylfluoride, polyvinylidenfluoride and polytetrafluoroethylene were taken up. Active species trapped in the polymer matrixes were identified and decay and reactivity of the species were also studied. On the basis of information from the electron microscopy and x-ray analysis, radiation effects on these polymers are described. In polytetrafluoroethylene produced by radiation polymerization, the relation between morphology and polymerization conditions and also the process of crystallization during polymerization were studied. (auth.)

  9. Characterization of radiation-induced emesis in the ferret

    International Nuclear Information System (INIS)

    King, G.L.

    1988-01-01

    Forty-eight ferrets (Mustela putorius furo) were individually head-shielded and radiated with bilateral 60 Co gamma radiation at 100 cGy min-1 at doses ranging between 49 and 601 cGy. The emetic threshold was observed at 69 cGy, the ED50 was calculated at 77 cGy, and 100% incidence of emesis occurred at 201 cGy. With increasing doses of radiation, the latency to first emesis after radiation decreased dramatically, whereas the duration of the prodromal period increased. Two other sets of experiments suggest that dopaminergic mechanisms play a minor role in radiation-induced emesis in the ferret. Twenty-two animals were injected either intravenously or subcutaneously with 30 to 300 micrograms/kg of apomorphine. Fewer than 50% of the animals vomited to 300 micrograms/kg apomorphine; central dopaminergic receptor activation was apparent at all doses. Another eight animals received 1 mg/kg domperidone prior to either 201 (n = 4) or 401 (n = 4) cGy radiation and their emetic responses were compared with NaCl-injected-irradiated controls (n = 8). At 201 cGy, domperidone significantly reduced only the total time in emetic behavior. At 401 cGy, domperidone had no salutary effect on radiation-induced emesis. The emetic responses of the ferret to radiation and apomorphine are compared with these responses in other vomiting species

  10. Origin of specific chromosome aberration in radiation-induced leukemia

    International Nuclear Information System (INIS)

    Ban, Nobuhiko; Kai, Michiaki; Masuno, Yoko

    2005-01-01

    The theme in the title is discussed from the four aspects of specific chromosome aberration (sAb) patterns in radiation-induced leukemia (RIL), possibility for radiation to induce the sAb in RIL, any evidence for participation of delayed aberration to form sAb and the proportion of such healthy humans as having the specifically rearranged genome. Data of sAb observed in leukemia of 25 A-bomb survivors and of 38 patients post radiotherapy of cancers give a rather common pattern. However, many inconsistent results are obtained for sAb in patients post radiotherapy, A-bomb survivors, residents living in radio-contaminated houses in Taipei, in vitro exposure, and Chernobyl residents. At present, any clear evidence is available neither for sAb derived from the delayed aberration nor for estimating the proportion with the specifically rearranged gene. As above, it is unlikely that radiation induces such a translocation abnormality as BCR-ABL specifically seen in leukemia, and this aspect will be important for studies on the genesis of RIL and its risk assessment. (S.I.)

  11. Radiation induced segregation and point defects in binary copper alloys

    International Nuclear Information System (INIS)

    Monteiro, W.A.

    1984-01-01

    Considerable progress, both theoretical and experimental, has been made in establishing and understanding the influence of factors such as temperature, time, displacement rate dependence and the effect of initial solute misfit on radiation induced solute diffusion and segregation. During irradiation, the composition of the alloy changes locally, due to defect flux driven non-equilibrium segregation near sinks such as voids, external surfaces and grain boundaries. This change in composition could influence properties and phenomena such as ductility, corrosion resistance, stress corrosion cracking, sputtering and blistering of materials used in thermo-nuclear reactors. In this work, the effect of 1 MeV electron irradiation on the initiation and development of segregation and defect diffusion in binary copper alloys has been studied in situ, with the aid of a high voltage electron microscope. The binary copper alloys had Be, Pt and Sn as alloying elements which had atomic radii less than, similar and greater than that of copper, respectively. It has been observed that in a wide irradiation temperature range, stabilization and growth of dislocation loops took place in Cu-Sn and Cu-Pt alloys. Whereas in the Cu-Be alloy, radiation induced precipitates formed and transformed to the stable γ phase. (Author) [pt

  12. International Activities in Radiation-Induced Carcinogenesis. Survey Paper

    Energy Technology Data Exchange (ETDEWEB)

    Komarov, E. [World Health Organization, Geneva (Switzerland)

    1969-11-15

    During the past 10 years special attention has been paid to the problem of late effects of radiation and in particular to radiation-induced carcinogenesis and leukaemogenesis. In the UNSCEAR report of 1958-1962 this.problem was mentioned as being of considerable importance from the point of view of estimation of risk to the population from environmental radiation. In 1964 a special report was prepared by UNSCEAR on radiation- induced carcinogenesis. In the ICRP publication No. 8, a chapter dealing with assessment of somatic risks discussed the problem of leukaemia and other neoplasms and particularly stressed the problem of thyroid carcinoma-and bone sarcoma. WHO panels of experts discussed the problem in 1960-1966 and made some recommendations for international activity in this field. In spite of the amount of scientific attention that has been given in recent years to experimental radiobiology in animals and lower forms, it has become abundantly clear that information directly applicable to humans is woefully inadequate and that there is a desperate need for carefully collected data from man on which to base public health planning and day to day work in radiation protection. This has long been recognized in the technical program of WHO in the emphasis given to the practical importance of epidemiology in human radiobiology and the degree to which it depends upon international collaboration.

  13. Individual repair of radiation-induced DNA double-strand breaks in lymphocytes. Implications for radiation-induced dermatitis in breast cancer

    International Nuclear Information System (INIS)

    Melchior, Patrick Wilhelm

    2011-01-01

    Purpose: Adjuvant 'whole breast radiotherapy' (WBRT) is the standard of care after breast conserving surgery in women with breast cancer. Throughout different cancer stages the addition of WBRT leads to significantly improved rates of freedom from local failure and overall survival. WBRT is generally well tolerated. A 5-10%-rate of severe acute or long-term side effects is commonly observed. For both radiation-mediated tumor-cell-elimination and induction of side effects, DNA-double-strand-breaks (DSB) presumably play the decisive role. The intensity of normal tissue reactions in radiotherapy can, in part, be attributed to the intrinsic DSB repair-capacity. In this study in vivo and in vitro experiments are carried through in order to assess DSB repair-kinetics in blood lymphocytes of women with breast cancer. These findings are to be correlated with the degree of radiation-induced normal tissue toxicity. Patients and Methods: Eighteen patients with breast cancer, in whom WBRT was indicated, were examined. A total WBRT dose of 50 Gy (single dose 2 Gy) with an additional boost-radiotherapy to the initial tumor-region to a total dose of 60-66 Gy was administered. DSB repair was determined by means of counting γ-H2AX foci in blood lymphocytes at predefined points in time, i.e. before and 0.5 h; 2.5 h; 5 h and 24 h after in vivo irradiation (1st fraction of WBRT) and before and 0.5 h; 2.5 h and 5 h after in vitro irradiation with increasing radiation doses in the range of 10 - 500 mGy. Acute normal tissue toxicity was scored on the basis of a modified RTOG-classification (main aspects were erythema and dry or moist skin desquamation). Results: DSB repair-halflife-times did not differ between patients with a higher or lower than average incidence of acute side effects. In patients with 'above average' side effects larger irradiation volumes were treated (volume surrounded by the 50%-isodose). Adjusted for these, no single patients showed elevated residual γ-H2AX foci

  14. Clinical and Functional Assays of Radiosensitivity and Radiation-Induced Second Cancer

    Directory of Open Access Journals (Sweden)

    Mohammad Habash

    2017-10-01

    Full Text Available Whilst the near instantaneous physical interaction of radiation energy with living cells leaves little opportunity for inter-individual variation in the initial yield of DNA damage, all the downstream processes in how damage is recognized, repaired or resolved and therefore the ultimate fate of cells can vary across the population. In the clinic, this variability is observed most readily as rare extreme sensitivity to radiotherapy with acute and late tissue toxic reactions. Though some radiosensitivity can be anticipated in individuals with known genetic predispositions manifest through recognizable phenotypes and clinical presentations, others exhibit unexpected radiosensitivity which nevertheless has an underlying genetic cause. Currently, functional assays for cellular radiosensitivity represent a strategy to identify patients with potential radiosensitivity before radiotherapy begins, without needing to discover or evaluate the impact of the precise genetic determinants. Yet, some of the genes responsible for extreme radiosensitivity would also be expected to confer susceptibility to radiation-induced cancer, which can be considered another late adverse event associated with radiotherapy. Here, the utility of functional assays of radiosensitivity for identifying individuals susceptible to radiotherapy-induced second cancer is discussed, considering both the common mechanisms and important differences between stochastic radiation carcinogenesis and the range of deterministic acute and late toxic effects of radiotherapy.

  15. The Protective Role of Ginkgo Biloba against Radiation Induced Injury on Rat Gastro-intestinal Tract

    International Nuclear Information System (INIS)

    El-Ghazaly, M.A.; Gharib, O.A.; El-Sheikh, M.M.; Khayyal, M.T.

    2015-01-01

    Ginkgo Biloba extract (EGb 761) is an antioxidant substance exhibits a wide variety of biological activities. The present study was performed to evaluate oxidative stress and inflammatory parameters of gastrointestinal injury induced by exposing rats to acute doses of γ-rays and the potential value of EGb 761 in preventing changes in these parameters. Male albino rats were treated orally with the extract in a dose of 100 mg/ kg for 7 successive days before whole body exposure to acute radiation levels of 2 and 6 Gray (Gy). Control groups were run concurrently. The rats were sacrificed 3 days after irradiation. Various inflammatory mediators and biochemical parameters were determined in the stomach and intestine. Both tissues were also examined histopathologically. Exposure to radiation led to dose dependent changes in the level of oxidative stress biomarkers (elevation of thiobarbituric acid reactive substance (TBARS) and nitrite associated with a glutathione (GSH) decrease as well as in the level of inflammatory parameters (elevation of Tumour necrosis factorα (TNF-α) and myeloperoxidase (MPO) associated with depletion of prostaglandin E 2 (PGE 2 ). Pre-treatment with EGb 761 protected against the changes in both oxidative stress biomarkers and inflammatory mediators. EGb 761 exerted a protective effect against the radiation induced gastrointestinal damage, possibly through its anti-inflammatory and anti-oxidant properties.

  16. Effectiveness of the herbal medicine daikenchuto for radiation-induced enteritis.

    Science.gov (United States)

    Takeda, Takashi; Kamiura, Shouji; Kimura, Tadashi

    2008-07-01

    Radiation-induced enteritis is a serious clinical problem for which there is currently no recommended standard management. Daikenchuto (DKT) is a Japanese herbal medicine that has been used to treat adhesive bowel obstruction in Japan. This report describes a patient with radiation-induced enteritis whose clinical symptoms were much improved by treatment with DKT. The patient was administered DKT, a traditional Japanese herbal formula, orally (2.5 g 3 times daily). Abdominal distention was evaluated objectively with computed tomography. Gastrointestinal symptoms associated with radiation-induced enteritis were controlled successfully with DKT treatment. DKT treatment may be useful for the management of radiation-induced enteritis.

  17. Radiation-induced Pulmonary Damage in Lung Cancer Patients

    International Nuclear Information System (INIS)

    Chung, Su Mi; Choi, Ihl Bohng; Kang, Mi Mun; Kim, In Ah; Shinn, Kyung Sub

    1993-01-01

    Purpose: A retrospective analysis was performed to evaluate the incidence of radiation induced lung damage after the radiation therapy for the patients with carcinoma of the lung. Method and Materials: Sixty-six patients with lung cancer (squamous cell carcinoma 27, adenocarcinoma 14, large cell carcinoma 2, small cell carcinoma 13, unknown 10) were treated with definitive, postoperative or palliative radiation therapy with or without chemotherapy between July 1987 and December 1991. There were 50 males and 16 females with median age of 63 years(range: 33-80 years). Total lung doses ranged from 500 to 6,660 cGy (median 3960 cGy) given in 2 to 38 fractions (median 20) over a range of 2 to 150 days (median 40 days) using 6 MV or 15 MV linear accelerator. To represent different fractionation schedules of equivalent biological effect, the estimated single dose(ED) model, ED=D·N-0.377·T-0.058 was used in which D was the lung dose in cGy, N was the number of fractions, and T was the overall treatment time in days. The range of ED was 370 to 1357. The endpoint was a visible increase in lung density within the irradiated volume on chest X-ray as observed independently by three diagnostic radiologists. Patients were grouped according to ED, treatment duration, treatment modality and age, and the percent incidence of pulmonary damage for each group was determined. Result: In 40 of 66 patients, radiation induced change was seen on chest radiographs between 11 days and 314 days after initiation of radiation therapy. The incidence of radiation pneumonitis was increased according to increased ED, which was statistically significant (p=0.001). Roentgenographic charges consistent with radiation pneumonitis were seen in 100% of patients receiving radiotherapy after lobectomy or pneumonectomy, which was not statistically significant. In 32 patients who also received chemotherapy, there was no difference in the incidence of radiation induced charge between the group with radiation

  18. Hereditary Factors Involved in Radiation-Induced Leukaemogenesis

    International Nuclear Information System (INIS)

    Duplan, J.F.

    1969-01-01

    The hereditary factors involved in radiation-induced leukaemogenesis were studied in pure AKR and C57BL strains, their first-generation hybrids and their back-crosses. It is known that the heredity of spontaneous lymphoid leukaemias is attributable to hereditary factors, of which only some are chromosomal, and the same situation can be considered to exist as regards the heredity of radiation-induced leukoses. In order to identify the various chromosomal and non-chromosomal factors concerned, three types of experiment were conducted with the pure strains and with each of the crosses, intended to evaluate (a) the incidence of spontaneous lymphoid leukoses, (b) the incidence of radiation-induced leukoses and (c) the inhibition of radioleukaemo- genesis by the injection of isogenic haematopoietic cells. The results show that the main non-chromosomal factor is the leukaemogenic Gross virus (VG) in the case of the AKR strain and the radioleukaemia virus (VRL) in that of the C57BL strain; these two agents are transmitted by the mother to her progeny. The VG may be responsible for radioleukaemias as well as for spontaneous leukoses, but the VRL does not produce spontaneous leukaemias even in back-crosses possessing a substantial fraction of the AKR genome, which is particularly conducive to leukaemogenesis. Restoration using C57BL bone marrow brings about a distinct inhibition of leukaemogenesis in all animals deriving from crossings for which this material is histocompatible; AKR marrow, however, never exhibits any restorative activity. Three hypotheses may be put forward to explain these results. The first is that C57BL bone marrow contains many more precursor elements than AKR marrow, these cells being necessary for inhibition of the leukaemogenic process. The second hypothesis is that the AKR strain lacks a factor which is essential for the utilization of these precursors. Finally the third hypothesis, which seems the least probable, is that AKR cells are much more

  19. Effect of pH on radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Chang, W. Song; Park, Heon J.; Lyons, John C.; Auger, Elizabeth A.; Lee, Hyung-Sik

    1996-01-01

    Purpose/Objective: The effect of environmental pH on the radiation-induced apoptosis in tumor cells in vitro was investigated. Materials and Methods: SCK mammary adenocarcinoma cells of A/J mice were irradiated with γ-rays using a 137 Cs irradiator and incubated in media of different pHs. After incubation at 37 degree sign C for 24-120 hrs., the extent of apoptosis was determined using agarose gel electrophoresis of DNA, in situ TUNEL staining, flow cytometry, and release of 3 H from 3 H-thymidine labeled cells. The membrane integrity, using the trypan blue exclusion method, and the clonogenicity of the cells were also determined. Results: Irradiation with 2-12 Gy of γ-rays induced apoptosis in pH 7.5 medium within 48 hrs. The radiation-induced apoptosis progressively declined as the medium pH was lowered so that little apoptosis occurred in 48 hrs. after irradiation with 12 Gy in pH 6.6 medium. However, when the cells were irradiated and incubated for 48 hrs. in pH 6.6 medium and then medium was replaced with pH 7.5 medium, apoptosis promptly occurred. Apoptosis also occurred even in pH 6.6 medium when the cells were irradiated and maintained in pH 7.5 medium for 8 hrs. or longer post-irradiation before incubation in pH 6.6 medium. Conclusion: An acidic environment markedly suppresses radiation-induced apoptosis probably by suppressing the expression of initial signals responsible for irradiation-induced apoptosis. Indications are that the signals persist in an acidic environment and trigger apoptosis when the environmental acidity is eased. Our results suggest that the acidic environment in human tumors may inhibit the apoptosis after irradiation. However, apoptosis may be triggered when reoxygenation occurs after irradiation, and thus, the intratumor environment becomes less acidic after irradiation. Not only the change in pO 2 but the change in pH during the course of fractionated radiotherapy may greatly influence the outcome of the treatment

  20. Radiation-induced apoptosis in undifferentiated cells of the developing brain as a biological defense mechanism

    International Nuclear Information System (INIS)

    Inouye, Minioru; Tamaru, Masao.

    1994-01-01

    Undifferentiated neural (UN) cells of the developing mammalian brain are highly sensitive to the lethal effects of ionizing radiation. Nuclear and cytoplasmic condensation, transglutaminase activation, and internucleosomal DNA cleavage reveal radiation-induced cell death in the ventricular zone of the cerebral mantle and external granular layer of the cerebellum to be due to apoptosis. A statistically significant increase of cell mortality can be induced by 0.03 Gy X-irradiation, and the mortality increases linearly with increasing doses. It is not changed by split doses, probably because of the very slow repair of cellular damage and a lack of adaptive response. Although extensive apoptosis in the UN cell population results in microcephaly and mental retardation, it possesses the ability to recover from a considerable cell loss and to form the normal structure of the central nervous system. The number of cell deaths needed to induce tissue adnormalities in the adult murine brain rises in the range of 15-25% of the germinal cell population; with the threshold doses at about 0.3 Gy for cerebral anomalies and 1 Gy for cerebellar abnormalities. Threshold level is similarly suggested in prenatally exposed A-bomb survivors. High radiosensitivity of UN cells is assumed to be a manifestation of the ability of the cell to commit suicide when injured. Repeated replication of DNA and extensive gene expression are required in future proliferation and differentiation. Once an abnormality in DNA was induced and fixed in the UN cell, it would be greatly amplified and prove a danger in producing malformations and tumors. These cells would thus commit suicide for the benefit of the individual to eliminate their acquired genetic abnormalities rather than make DNA repair. UN cells in the developing brain are highly radiosensitive and readily involved in apoptosis. Paradoxically, however, this may be to protect individuals against teratogenesis and tumorigenesis. (J.P.N.)

  1. Radiation-induced apoptosis in undifferentiated cells of the developing brain as a biological defense mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Inouye, Minioru [Nagoya Univ. (Japan). Research Inst. of Environmental Medicine; Tamaru, Masao

    1994-12-31

    Undifferentiated neural (UN) cells of the developing mammalian brain are highly sensitive to the lethal effects of ionizing radiation. Nuclear and cytoplasmic condensation, transglutaminase activation, and internucleosomal DNA cleavage reveal radiation-induced cell death in the ventricular zone of the cerebral mantle and external granular layer of the cerebellum to be due to apoptosis. A statistically significant increase of cell mortality can be induced by 0.03 Gy X-irradiation, and the mortality increases linearly with increasing doses. It is not changed by split doses, probably because of the very slow repair of cellular damage and a lack of adaptive response. Although extensive apoptosis in the UN cell population results in microcephaly and mental retardation, it possesses the ability to recover from a considerable cell loss and to form the normal structure of the central nervous system. The number of cell deaths needed to induce tissue adnormalities in the adult murine brain rises in the range of 15-25% of the germinal cell population; with the threshold doses at about 0.3 Gy for cerebral anomalies and 1 Gy for cerebellar abnormalities. Threshold level is similarly suggested in prenatally exposed A-bomb survivors. High radiosensitivity of UN cells is assumed to be a manifestation of the ability of the cell to commit suicide when injured. Repeated replication of DNA and extensive gene expression are required in future proliferation and differentiation. Once an abnormality in DNA was induced and fixed in the UN cell, it would be greatly amplified and prove a danger in producing malformations and tumors. These cells would thus commit suicide for the benefit of the individual to eliminate their acquired genetic abnormalities rather than make DNA repair. UN cells in the developing brain are highly radiosensitive and readily involved in apoptosis. Paradoxically, however, this may be to protect individuals against teratogenesis and tumorigenesis. (J.P.N.).

  2. Sucralfate gel as a radioprotector against radiation induced dermatitis in a hypo-fractionated schedule: a non-randomized study.

    Science.gov (United States)

    Kouloulias, V; Asimakopoulos, C; Tolia, M; Filippou, G; Platoni, K; Dilvoi, M; Beli, I; Georgakopoulos, J; Patatoukas, G; Kelekis, N

    2013-04-01

    External beam radiotherapy with high doses provokes many acute skin reactions, such as erythema and moist desquamation. Many topical preparations are used in radiation oncology departments in the skin care. Sucralfate humid gel, a colloidal physical form of the anti-ulcer drug sucralfate, promotes epithelial regeneration and activates cell proliferation. Based on this knowledge, we performed a non-randomized clinical trial to evaluate the efficacy of topical sucralfate gel in 30 breast cancer patients receiving postoperative accelerated hypofractionated photon beam therapy. The comparison was performed with 30 patients as historical controls. The acute reaction of the skin was significantly lower in the group receiving the sucralfate gel (p<0.05, Mann Whitney test), while 90% of the patients had no evidence of radiation induced skin toxicity. There was no sucralfate gel related toxicity reported by any patient in this study. More patients in a randomized way are needed for more definite results.

  3. Proteome analysis of Radiation-induced pulmonary fibrosis

    International Nuclear Information System (INIS)

    Song, Jie Young; Lim, Hee Soon; Kim, Hyung Doo; Shim, Ji Young; Han, Young Soo; Son, Hyeog Jin Son; Yun, Yeon Sook

    2005-01-01

    Pulmonary fibrosis is perhaps the most universal late effect of organ damage after both chemical insult and irradiation in the treatment of lung cancer. The use chemotherapy and radiation therapy, alone or combined, can be associated with clinically significant pulmonary toxicity, which leads to pneumonia and pulmonary fibrosis. It is also reported that about 100,000 people in the United States are suffered from pulmonary fibrosis. Therefore, pulmonary fibrosis will be more focused by medicinal researchers. Because current therapies, aimed at inhibiting pulmonary inflammation that often precedes fibrosis, are effective only in a minority of suffered patients, novel therapeutic methods are highly needed. Some researchers have used bleomycininduced pulmonary fibrosis as a basis for looking at the molecular mechanisms of fibrosis, and total gene expression was monitored using genomics method. However, radiation-induced pulmonary fibrosis has not been fully focused and investigated. Here, we have analyzed changes in gene expression in response to γ- irradiation by using proteomic analysis

  4. Acupuncture treatment of patients with radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Blom, M.; Dawidson, I.; Johnson, G.; Angmar-Maansson, B.; Fernberg, J.-O.

    1996-01-01

    Xerostomia is a common and usually irreversible side effect in patients receiving radiation therapy (>50 Gy) for head and neck cancer. Of 38 patients with radiation-induced xerostomia, 20 in the experimental group were treated with classical acupuncture and 18 patients in the control group received superficial acupuncture as placebo. Within both groups the patients showed significantly increased salivary flow rates after the acupuncture treatment. In the experimental group 68% and in the control group 50% of the patients had increased salivary flow rates at the end of the observation period. Among those patients who had had all their salivary glands irradiated, 50% in both groups showed increased salivary flow rates (>20%) by the end of the observation period of 1 year. The study indicates that among the patients who had increased salivary flow rates already after the first 12 acupuncture sessions, the majority had high probability of continual improvement after the completion of acupuncture treatment. (Author)

  5. Acupuncture treatment of patients with radiation-induced xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Blom, M.; Dawidson, I.; Johnson, G.; Angmar-Maansson, B. [Karolinska Inst., Huddinge (Sweden). Dept. of Cardiology; Fernberg, J.-O. [Karolinska Hospital, Stockholm (Sweden). Dept. of General Oncology

    1996-05-01

    Xerostomia is a common and usually irreversible side effect in patients receiving radiation therapy (>50 Gy) for head and neck cancer. Of 38 patients with radiation-induced xerostomia, 20 in the experimental group were treated with classical acupuncture and 18 patients in the control group received superficial acupuncture as placebo. Within both groups the patients showed significantly increased salivary flow rates after the acupuncture treatment. In the experimental group 68% and in the control group 50% of the patients had increased salivary flow rates at the end of the observation period. Among those patients who had had all their salivary glands irradiated, 50% in both groups showed increased salivary flow rates (>20%) by the end of the observation period of 1 year. The study indicates that among the patients who had increased salivary flow rates already after the first 12 acupuncture sessions, the majority had high probability of continual improvement after the completion of acupuncture treatment. (Author).

  6. Contribution of bystander effects in radiation induced genotoxicity

    International Nuclear Information System (INIS)

    Zhou, H.; Persaud, R.; Gillispie, J.; Randers-Pehrson, G.; Hei, T.K.; Suzuki, Masao

    2005-01-01

    The controversial use of a linear, no threshold extrapolation model for low dose risk assessment is based on the accepted dogma that the deleterious effects of ionizing radiation such as mutagenesis and carcinogenesis are attributable mainly to direct damage to DNA. However, this extrapolation was challenged by the recent reports on the bystander phenomenon. The bystander effect contributes to this debate by implying that the biological effects of low doses, where not all cells are traversed by a charged particle, are amplified by the transfer of factors to un-irradiated neighbors. This interested phenomenon implies that a linear extrapolation of risks from high to low doses may underestimate rather than over estimate low dose risks. Together with some radiation-induced phenomena such as adaptive response and genomic instability, the radiobiological response at low doses is likely to be a complex interplay among many factors. (author)

  7. Radiation-induced degradation of 4-chloroaniline in aqueous solution

    International Nuclear Information System (INIS)

    Sanchez, M.; Wolfger, H.; Getoff, N.

    2002-01-01

    The radiation-induced decomposition of 4-chloroaniline (4-ClA) was studied under steady-state conditions using aqueous solutions saturated with air, pure oxygen, N 2 O, argon and argon in the presence of t-Butanol. Using HPLC-method, the initial G-values of the substrate degradation as well as of a number of radiolytic products were determined. The formation of aminophenols, chlorophenols, aniline and phenol in addition to chloride, ammonia, formaldehyde and mixture of aldehydes as well as carboxylic acids was studied as a function of absorbed dose. Based on the experimental data, probable reaction mechanisms for the degradation of 4-ClA by γ-rays and the formation of the identified products are presented

  8. Radiation-induced decomposition of anion exchange resins

    International Nuclear Information System (INIS)

    Baidak, Aliaksandr; LaVerne, Jay A.

    2010-01-01

    Radiation-induced degradation of the strongly basic anion exchange resin Amberlite TM IRA400 in NO 3 - , Cl - and OH - forms has been studied. The research focused on the formation of molecular hydrogen in the gamma-radiolysis of water slurries of these quaternary ammonium resins with varying water content. Extended studies with various electron scavengers (NO 3 - , N 2 O and O 2 ) prove an important role of e solv - in the formation of H 2 from these resins. An excess production of H 2 in these systems at about 85% water weight fraction was found to be due to trimethylamine, dimethylamine and other compounds that leach from the resin to the aqueous phase. Irradiations with 5 MeV 4 He ions were performed to simulate the effects of α-particles.

  9. Structure and radiation induced swelling of steels and alloys

    International Nuclear Information System (INIS)

    Parshin, A.M.

    1983-01-01

    Regularities of vacancy void formation and radiation induced swelling of austenitic chromium-nickel steels and alloyse ferritic steels as well as titanium α-alloys under radiation by light and heavy ions and neutrons are considered. Possible methods for preparation of alloys with increased resistance to radiation swelling are described. Accounting for investigations into ferritic steels and α-alloys of titanium the basic way of weakening vacancy smelling is development of continuous homogeneous decomposition of solid solution using alloying with vividly expressed incubation period at a certain volumetric dilatation as well as decompositions of the type of ordering, K-state, lamination of solid solutions, etc. Additional alloying of solid solutions is also shown to be necessary for increasing recrystallization temperature of cold-deformed steel

  10. Radiation-induced degradation of chlorophenols in aqueous solution

    International Nuclear Information System (INIS)

    Hu Jun; Wang Jianlong

    2005-01-01

    Radiation processing is a promising technology for applications in environmental protection, which includes wastewater treatment, micro-polluted drinking water treatment and the treatment of industrial wastewater containing various toxic and nonbiodegradable pollutants, municipal sewage and sludge disinfection, and flue gas desulfuration, etc. The paper reviews manly the recent progresses in radiolysis of chlorinated phenols in aqueous solution. Advantages and existing problems of the method in this particular application ar discussed. Mechanisms of radiation-induced degradation of chlorophenols, and the factors affecting the degradation efficiency, are discussed, too. It is concluded that combined approaches, such ozone oxidation and other methods, are of great help to the radiation processing application, in terms of lowering down the dose and increasing the efficient of pollutant removal. (authors)

  11. Radiation-induced spindle cell sarcoma: A rare case report

    Directory of Open Access Journals (Sweden)

    Khan Mubeen

    2009-01-01

    Full Text Available Ionizing radiation has been known to induce malignant transformation in human beings. Radiation-induced sarcomas are a late sequel of radiation therapy. Most sarcomas have been reported to occur after exposure to a radiation dose of 55 Gray (Gy and above, with a dose ranging from 16 to 112 Gys. Spindle cell sarcomas, arising after radiotherapy given to treat the carcinoma of head and neck region is a very uncommon sequel. This is a rare case report of spindle cell sarcoma of left maxilla, in a 24-year-old male, occurring as a late complication of radiotherapy with Cobalt-60 given for the treatment of retinoblastoma of the left eye 21 years back.

  12. Induction, development, and inhibition of radiation-induced macrobodies

    International Nuclear Information System (INIS)

    Adam, W.J.; Grunewald, R.

    1975-01-01

    Coleus shoots were exposed to 100,000 R of γ radiation and the fine structure of the apical meristems was examined. Meristems were fixed at various postirradiation times. An ultrastructural body was found associated with irradiated tissue, bound by a single membrane, containing dense osmiophilic bodies, and usually associated with radiation-induced vacuoles. The development of these new bodies, and the effects of both dose rate and light during the postirradiation period on their development were examined. Reduction of the dose rate by a factor of two inhibited the formation of these macrobodies through the 24 hour postirradiation period. Meristems kept in the dark during the 24 hour postirradiation period had macrobodies similar in form to the macrobodies from the meristems of the 16 hour postirradiation period which were exposed to light. Superlethal doses were used to achieve these results. Similarities between our results and those achieved with lower lethal doses are discussed

  13. Controlled release of biofunctional substances by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Yoshida, M.; Kumakura, M.; Kaetsu, I.

    1978-01-01

    The controlled release of potassium chloride from flat circular matrices made by radiation-induced polymerization of a glass-forming monomer at low temperatures has been studied. The water-particle phase content formed in a poly(diethylene glycol dimethacrylate) matrix was controlled by the addition of polyethylene glycol 600. The dispersed water-particle phase content in the matrix was estimated directly and by scanning electron microscopic observations. The release of potassium chloride from the matrix increased linearly with the square root of time. The water content of the matrix had an important effect on the release rate which increases roughly in proportion to water content. This effect can be attributed to the apparent increase of the rate of drug diffusion. (author)

  14. Controlled release of biofunctional substances by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Yoshida, M.; Kumakura, M.; Kaetsu, I.

    1978-01-01

    The release behaviour of a drug from flat circular capsules obtained by radiation-induced polymerization at low temperatures and with different hydrophilic properties has been studied. The effect of various factors on release property was investigated. The release process could be divided into three parts, an initial quick release stage, stationary state release stage and a retarded release stage. Release behaviour in the stationary state was examined using Noyes-Whitney and Higuchi equations. It was shown that the hydrophilic property of polymer matrix expressed by water content was the most important effect on diffusion and release rate. Rigidity of the polymer may also affect diffusivity. The first quick release step could be attributed to rapid dissolution of drug in the matrix surface due to polymer swelling. (author)

  15. Liv. 52 protection against radiation induced lesions in mammalian liver

    International Nuclear Information System (INIS)

    Saini, M.R.; Saini, N.

    1985-01-01

    Effect of Liv. 52 on mammalian liver was studied after whole-body exposure to 5.5 Gy of 60 Co gamma radiation. It was found that the drug protected the organ against radiation-induced changes. The protective effect was manifested in the form of early recovery as indicated by the absence of pathological changes like cytoplasmic degranulation, loss of nulei from many cells and abnormal architecture at 10 days and restoration of normal structure by 4 weeks. Liv. 52 may neutralize the peroxides formed from water molecules after irradiation which are toxic and cause the damage to the organ. Thus it seems that the drug may act as detoxicating agent. (author)

  16. Radiatively induced breaking of conformal symmetry in a superpotential

    International Nuclear Information System (INIS)

    Arbuzov, A.B.; Cirilo-Lombardo, D.J.

    2016-01-01

    Radiatively induced symmetry breaking is considered for a toy model with one scalar and one fermion field unified in a superfield. It is shown that the classical quartic self-interaction of the superfield possesses a quantum infrared singularity. Application of the Coleman–Weinberg mechanism for effective potential leads to the appearance of condensates and masses for both scalar and fermion components. That induces a spontaneous breaking of the initial classical symmetries: the supersymmetry and the conformal one. The energy scales for the scalar and fermion condensates appear to be of the same order, while the renormalization scale is many orders of magnitude higher. A possibility to relate the considered toy model to conformal symmetry breaking in the Standard Model is discussed.

  17. Radiation-induced malignant tumors of skin and their histogenesis

    International Nuclear Information System (INIS)

    Li Guomin; Chen Yunchi; Yang Yejing

    1987-01-01

    Seven cases of radiation-induced malignant tumors and 60 cases of chronic radiation damage of skin are reported. Severe hyperplasia, false epitheliomatoid hyperpiasia and atypical proliferation of epithelia and atypical proliferation of fibrohistocytes were the main changes found in chronic radiation damage of skin. The development of malignant tumors from chronic radiation damage of skin can be divided into 4 periods: necrotic and degenerative change period, benign proliferative period, atypical proliferative period and malignant change period. The incidence of hyperplastic changes of skin is related to the time elapse after irradiation and the integrated dose of radiation. The longer the duration after irradiation and the larger the integrated dose are, the higher will be the incidence of hyperplastic changes

  18. Radiation induced phosphorus segregation in austenitic and ferritic alloys

    International Nuclear Information System (INIS)

    Brimhall, J.L.; Baer, D.R.; Jones, R.H.

    1984-01-01

    The radiation induced surface segregation (RIS) of phosphorus in stainless steel attained a maximum at a dose of 0.8 dpa then decreased continually with dose. This decrease in the surface segregation of phosphorus at high dose levels has been attributed to removal of the phosphorus layer by ion sputtering. Phosphorus is not replenished since essentially all of the phosphorus within the irradiation zone has been segregated to the surface. Sputter removal can explain the previously reported absence of phosphorus segregation in ferritic alloys irradiated at high dosessup(1,2) (>1 dpa) since irradiation of ferritic alloys to low doses has shown measurable RIS. This sputtering phenomenon places an inherent limitation to the heavy ion irradiation technique for the study of surface segregation of impurity elements. The magnitude of the segregation in ferritics is still much less than in stainless steel which can be related to the low damage accumulation in these alloys. (orig.)

  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. Radiation-induced formation of cavities in amorphous germanium

    International Nuclear Information System (INIS)

    Wang, L.M.; Birtcher, R.C.

    1989-01-01

    Prethinned polycrystalline Ge TEM samples were irradiated with 1.5 MeV Kr + ions at room temperature while structural and morphological changes were observed in situ in the Argonne High Voltage Electron Microscope-Tandem Facility. After a Kr + dose of 1.2x10 14 ions/cm 2 , the irradiated Ge was completely amorphized. A high density of small void-like cavities was observed after a Kr + dose of 7x10 14 ions/cm 2 . With increasing Kr + ion dose, these cavities grew into large holes transforming the irradiated Ge into a sponge-like porous material after 8.5x10 15 ions/cm 2 . The radiation-induced nucleation of void-like cavities in amorphous material is astonishing, and the final structure of the irradiated Ge with enormous surface area may have potential applications

  1. Radiation-induced polymerization for the immobilization of penicillin acylase

    International Nuclear Information System (INIS)

    Boccu, E.; Carenza, M.; Lora, S.; Palma, G.; Veronese, F.M.

    1987-01-01

    The immobilization of Escherichia coli penicillin acylase was investigated by radiation-induced polymerization of 2-hydroxyethyl methacrylate at low temperature. A leak-proof composite that does not swell in water was obtained by adding the cross-linking agent trimethylolpropane trimethacrylate to the monomer-aqueous enzyme mixture. Penicillin acylase, which was immobilized with greater than 70% yield, possessed a higher Km value toward the substrate 6-nitro-3-phenylacetamidobenzoic acid than the free enzyme form (Km = 1.7 X 10(-5) and 1 X 10(-5) M, respectively). The structural stability of immobilized penicillin acylase, as assessed by heat, guanidinium chloride, and pH denaturation profiles, was very similar to that of the free-enzyme form, thus suggesting that penicillin acylase was entrapped in its native state into aqueous free spaces of the polymer matrix

  2. Distraction osteogenesis of radiation-induced orbitozygomatic hypoplasia.

    Science.gov (United States)

    Grover, Ramon; Murray, Dylan; Fialkov, Jeffrey A

    2008-05-01

    In the last decade, the application of distraction osteogenesis to the craniofacial skeleton has grown to include not only deformities of the mandible, but of the midface, palate, dentoalveolar region, and calvarium. A major advantage of distraction osteogenesis lies in the simultaneous soft tissue histogenesis that accompanies the bony distraction process, allowing for potentially lower relapse rates and improved cosmesis. Although this may seem appropriately suited to irradiation-induced deformities of both hard and soft tissues, there is little in the literature as to the efficacy of this technique in patients who have received radiotherapy. To introduce an effective application of this technology, and highlight some advantages and disadvantages of its application in the irradiated craniofacial skeleton, we present a case of distraction osteogenesis of the orbitozygomatic complex in a patient with radiation induced orbitozygomatic hypoplasia.

  3. Radiation-induced bilateral common carotid artery stenosis

    International Nuclear Information System (INIS)

    Kobayashi, Nobuaki; Nakagawa, Yoku; Tashiro, Kunio; Abe, Hiroshi

    1986-01-01

    A case of radiation-induced bilateral common carotid artery stenosis is reported. This 60 years old housewife was hospitalized in 1982 because of sudden onset of mild left hemiparesis. Twenty-five years ago, she underwent radiation therapy of approximately 5,000 rads to the anterior cervical region because of thyroid cancer. Angiograms in 1982 revealed bilateral common carotid artery stenosis, especially in the right common carotid artery, the legion of which were included within the field of radiation performed in 1952. Right thromboendarterectomy was performed in 1983. At operation, slight periarterial fibrosis with calcified arteriosclerotic change was found, and dissection between the thickened intima and the media was not so difficult. Histological change of resected thromboendarterium was similar to the one observed in the pure arteriosclerotic disease. (author)

  4. A review of radiation-induced demagnetization of permanent magnets

    Science.gov (United States)

    Samin, Adib J.

    2018-05-01

    Radiation-induced demagnetization of permanent magnets is important for a number of applications including space missions, particle accelerators and robots designed to carry out rescue missions at nuclear accidents where magnet failure can lead to serious consequences. This topic has been studied by several investigators over the past three decades and in this work, a review of the available literature is conducted and some general conclusions and trends are presented. In short, it can be gleaned that magnetism loss is dependent on the type of radiation, the energy of the incoming particle and the overall dose or fluence. Furthermore, magnetism loss also shows a dependence on the type of the irradiated magnet, the coercivity of the magnet, the demagnetizing field and the temperature of irradiation.

  5. Molecular analysis of radiation-induced mutations in vitro

    International Nuclear Information System (INIS)

    Kronenberg, A.

    1996-01-01

    This review will focus on the nature of specific locus mutations detected in mammalian cells exposed in vitro to different types of ionizing radiations. Ionizing radiation has been shown to produce a wide variety of heritable alterations in DNA. These range from single base pair substitutions to stable loss or translocation of large portions of whole chromosomes. Data will be reviewed for certain test systems that reveal different mutation spectra. Techniques for the analysis of molecular alterations include applications of the polymerase chain reaction, some of which may be coupled with DNA sequence analysis, and a variety of hybridization-based techniques. The complexity of large scale rearrangements is approached with cytogenetic techniques including high resolution banding and various applications of the fluorescence in situ hybridization (FISH) technique. Radiation-induced mutant frequencies and mutation spectra are a function of the linkage constraints on the recovery of viable mutants for a given locus and test system. 44 refs

  6. Kinetics of radiation-induced precipitation at the alloy surface

    Science.gov (United States)

    Lam, N. Q.; Nguyen, T.; Leaf, G. K.; Yip, S.

    1988-05-01

    Radiation-induced precipitation of a new phase at the surface of an alloy during irradiation at elevated temperatures was studied with the aid of a kinetic model of segregation. The preferential coupling of solute atoms with the defect fluxes gives rise to a strong solute enrichment at the surface, which, if surpassing the solute solubility limit, leads to the formation of a precipitate layer. The moving precipitate/matrix interface was accommodated by means of a mathematical scheme that transforms spatial coordinates into a reference frame in which the boundaries are immobile. Sample calculations were performed for precipitation of the γ'-Ni 3Si layer on Ni-Si alloys undergoing electron irradiation. The dependences of the precipitation kinetics on the defect-production rate, irradiation temperature, internal defect sink concentration and alloy composition were investigated systematically.

  7. Radiation induced defects and thermoluminescence mechanism in aluminum oxide

    Energy Technology Data Exchange (ETDEWEB)

    Atobe, K.; Kobayashi, T.; Awata, T. [Naruto Univ. of Education, Tokushima (Japan); Okada, M. [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst; Nakagawa, M. [Kagawa Univ., Faculty of Education, Takamatsu, Kagawa (Japan)

    2001-01-01

    The thermoluminescence of the irradiated aluminum oxides were measured to study the radiation induced defects and their behaviors. Neutron and {gamma}-ray irradiation were performed for a shingle crystal of the high purity aluminum oxide. The thermoluminescence glow curve and its activation energy were measured. The spectroscopy measurement on the thermoluminescence and the absorption are also carried out. The observed 430 and 340 nm peaks are discussed relating to the F{sup +} and F centers, respectively. Activation state of the F center transits to 3P state through 1P state by emitting phonons. Trapped electron on 3P state emits phonon of 2.9 eV (430 nm) during transition to the ground state. The above reaction can be written by the equation. F{sup +} + e {yields} (F){sup *} {yields} F + h{nu}(2.9 eV, 470 nm). (Katsuta, H.)

  8. Radiation induced crystallinity damage in poly(L-lactic acid)

    CERN Document Server

    Kantoglu, O

    2002-01-01

    The radiation-induced crystallinity damage in poly(L-lactic acid) (PLLA) in the presence of air and in vacuum, is studied. From the heat of fusion enthalpy values of gamma irradiated samples, some changes on the thermal properties were determined. To identify these changes, first the glass transition temperature (T sub g) of L-lactic acid polymers irradiated to various doses in air and vacuum have been investigated and it is found that it is independent of irradiation atmosphere and dose. The fraction of damaged units of PLLA per unit of absorbed energy has been measured. For this purpose, SAXS and differential scanning calorimetry methods were used, and the radiation yield of number of damaged units (G(-u)) is found to be 0.74 and 0.58 for PLLA samples irradiated in vacuum and air, respectively.

  9. Factors that modify risks of radiation-induced cancer

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1988-11-01

    The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors)

  10. Radiation induced mutant crop varieties: accomplishment and societal deployment

    International Nuclear Information System (INIS)

    D'Souza, S.F.

    2009-01-01

    One of the peaceful applications of atomic energy is in the field of agriculture. It finds application in crop improvement, crop nutrition, crop protection and food preservation. Genetic improvement of crop plants is a continuous endeavor. Success of a crop improvement programme depends on the availability of large genetic variability, which a plant breeder can combine to generate new varieties. In nature, occurrence of natural variability in the form of spontaneous mutations is extremely low (roughly 10 -6 ), which can be enhanced to several fold (approximately 10 -3 ) by using ionizing radiations or chemical mutagens. Radiation induced genetic variability in crop plants is a valuable resource from which plant breeder can select and combine different desired characteristics to produce better crop varieties. Crop improvement programmes at Bhabha Atomic Research Centre (BARC) envisage radiation based induced mutagenesis along with recombination breeding in country's important cereals (rice and wheat), oilseeds (groundnut, mustard, soybean and sunflower), grain legumes (blackgram, mungbean, pigeonpea and cowpea), banana and sugarcane

  11. Binding of radiation-induced phenylalanine radicals to DNA

    International Nuclear Information System (INIS)

    Schans, G.P. van der; Rijn, C.J.S. van; Bleichrodt, J.F.

    1975-11-01

    When an aqueous solution of double-stranded DNA of bacteriophage PM2 containing phenylalanine and saturated with N 2 O is irradiated with γ-rays, radiation-induced phenylalanine radicals are bound covalently. Under the conditions used about 25 phenylalanine molecules may be bound per lethal hit. Also for single-stranded PM2 DNA, most of the phenylalanine radicals bound are non-lethal. Evidence is presented that in double-stranded DNA an appreciable fraction of the single-strand breaks is induced by phenylalanine radicals. Radiation products of phenylalanine and the phenylalanine bound to the DNA decrease the sensitivity of the DNA to the induction of single-strand breaks. There are indications that the high efficiency of protection by radiation products of phenylalanine is due to their positive charge, which will result in a relatively high concentration of these compounds in the vicinity of the negatively charged DNA molecules

  12. Radiation-induced bone tumours in the guinea-pig

    International Nuclear Information System (INIS)

    Knowles, J.F.

    1981-01-01

    A remarkably high proportion of guinea-pigs given localized irradiations of 20 Gy x-rays developed bone tumours, 46% of all irradiated with 20 Gy and 86% of those that survived at least a year. Untreated controls were not included in the present experiment, but the authors refer to an earlier experiment using guinea-pigs from the same colony where no bone tumour occurred in 69 unirradiated animals followed for their natural life span i.e. up to 87 months. It is concluded that the author's strain of guinea-pig (details given in a previous paper, Int. J. Radiol. Biol., 40, 265) is particularly prone to radiation-induced bone tumours. Their possible value for investigating processes associated with radiation induction of bone tumours is further enhanced by their relatively large size and long life span (up to 7 years). (U.K.)

  13. Gamma radiation induced and natural variability for nodulation in legumes

    Energy Technology Data Exchange (ETDEWEB)

    Maherchandani, N; Rana, O P.S. [Haryana Agricultural Univ., Hissar (India). Dept. of Genetics

    1977-09-01

    Gamma radiation induced variability for nodulation was studied in 112 M4 mutant lines of cowpea variety C-15-2. Ten lines superior in nodulation to the original variety have been identified. Natural variability for nodulation and plant growth was investigated in 75 genotypes of chickpea. A number of genotype were found to be superior to cultivated variety C-235 for nodulation characters. Nodule characters were found to be related to dry matter accumulation but not to grain yield. Another experiment on 10 varieties of chick pea conducted under aseptic conditions revealed that host genotypes showed specificity for Rhizobial strains and different Rhizobial strains differed in their effectiveness on different host genotypes. H 551 and H 355 were the most responsive varieties.

  14. Non-radiation induced signals in TL dosimetry

    International Nuclear Information System (INIS)

    German, U.; Weinstein, M.

    2002-01-01

    One source of background signals, which are non-radiation related, is the reader system and it includes dark current, external contaminants and electronic spikes. These factors can induce signals equivalent to several hundredths of mSv. Mostly, the effects are minimised by proper design of the TLD reader, but some effects are dependent on proper operation of the system. The other main group of background signals originate in the TL crystal and is due to tribothermoluminescence, dirt, chemical reactions and stimulation by visible or UV light. These factors can have a significant contribution, equivalent to over several mSv, depending on whether the crystal is bare or protected by PTFE. Working in clean environments, monitoring continuously the glow curve and performing glow curve deconvolution are suggested to minimise non-radiation induced spurious signals. (author)

  15. Radiological-morphological synopsis of radiation-induced lung fibrosis

    International Nuclear Information System (INIS)

    Bublitz, G.

    1977-01-01

    As delayed radiation damage after treatment of bronchial carcinoma and mamma carcinoma, fibroses occur as a reaction of the tissues. They have become a clinical-functional syndrome because of their uniform clinicaL-radiological symptomatology and pathophysiology. Pulmonary fibrosis as delayed radiation damage has a special importance with its two different radiation effects on connective tissue: a) on existing structures, b) delayed alterations of the connective tissue. As seen from experiments on lungs of men and rats, radiation-induced alterations can be measured by testing the different solubilities of the collagen types. In addition to the pathologically disordered collagen production, 9 weeks after the irradiation the radiation fibrosis leads to an isolated increase of insoluble collagen corresponding to the formation of metabolism-resistant fibrils. (MG) [de

  16. Radiation-induced crosslinking of poly(vinylidene fluoride)

    International Nuclear Information System (INIS)

    Makuuchi, Keizo

    1977-07-01

    The factors influencing radiation-induced crosslinking efficiency of poly(vinylidene fluoride) (PVdF) have been studied. Results of the basic research on irradiation conditions (dose rate and atmosphere) and initial physical properties of PVdF (structure of molecular chain and molecular mobility of chain segment) showed that crosslinking efficiency is raised in irradiation at high temperature above 50 0 C under vacuum in the presence of an absorbent for the evolved hydrogen fluoride. The crosslinking reaction is also accelerated with irregular molecular structure such as head-to-head bond in main chain. High crosslinking efficiency is obtained by addition of a polyfunctional monomer having good solubility with PVdF. Mechanical properties of PVdF, the strength at high temperature near the melting point in particular, are improved by crosslinking in the presence of a polyfunctional monomer. (auth.)

  17. Studies on radiation induced changes in bovine hemoglobin type A

    International Nuclear Information System (INIS)

    Wdzieczak, J.; Duda, W.; Leyko, W.

    1978-01-01

    In this paper the structural and functional changes of gamma irradiated bovine hemoglobin are presented. Aqueous solutions/1%/of HbO 2 were irradiated in air with doses ranging from 1 to 4 Mrad. Isoelectric focusing indicated change of the charge of irradiated hemoglobin. The isoelectric point of hemoglobin was displaced towards more acid values with increasing doses, up from 1 Mrad. Fingerprint analysis and peptide column chromatography of irradiated hemoglobin demonstrated disturbances increasing with the dose. These changes were confirmed by amino acid analysis which showed that Cys, Met, Trp, His, Pro and Tyr residues were destroyed or modified following irradiation. At doses exceeding 1 Mrad the irradiated solutions of hemoglobin showed a decrease of heme-heme interaction and an increase of affinity for oxygen. Differences observed in oxygen-dissociation curves seem to be correlated with the radiation induced destruction of amino acid residues which are responsible for the functional properties of hemoglobin. (auth.)

  18. Radiation-induced DNA damage and cellular lethality

    International Nuclear Information System (INIS)

    Sakai, K.; Okada, S.

    1984-01-01

    Radiation-induced DNA scissions and their repair were investigated in mammalian cells using an alkaline separation method. DNA breaks in mouse L5178Y cells and Chinese hamster V79 cells were grouped into three in terms of their repair profile; fast-reparable breaks (FRBs; T1/2 = 5 min), slow-reparable breaks (SRBs; T1/2 = 70 min) and non-reparable breaks (NRBs). The three types of DNA lesions were studied under conditions where cellular radiosensitivity was modified. The authors obtained the following results: 1. Cell cycle fluctuation: L5178Y showed maximum sensitivity at M and G/sub 1/-S boundary, and minimum sensitivity at G/sub 1/ and late S. Cycle dependency was not found for FRBs or SRBs, but NRBs showed bimodal fluctuation with peaks at M and G/sub 1/-S, and with bottoms at G/sub 1/ and late S. 2. Different sensitivity of L5178Y and V79: L5178Y cells were more sensitive to X-rays (D/sub ο/ = 0.9 Gy) than V79 (D/sub ο/ = 1.8 Gy). The amount of FRBs or SRBs was identical in the two cell lines. However, the amount of NRBs in L5178Y was greater than that in V79. 3. Split dose irradiation: The time interval between two doses resulted in a gradual decrease of NRBs. The time course of the decrease was similar to the split dose recovery in terms of cell death. The parallel relationship between NRBs and cell killing implies that NRBs could play an important role in radiation-induced cell death

  19. Association of single nucleotide polymorphisms with radiation-induced esophagitis

    International Nuclear Information System (INIS)

    Zhang Li; Wang Lvhua; Yang Ming; Ji Wei; Zhao Lujun; Yang Weizhi; Zhou Zongmei; Ou Guangfei; Lin Dongxin

    2008-01-01

    Objective: To evaluate the relationship between single nucleotide polymorphism(SNP) of candidate genes and radiation-induced esophagitis (RIE) in patients with lung cancer. Methods: Between Jan. 2004 and Aug. 2006, 170 patients with pathologically diagnosed lung cancer were enrolled in this study. The total target dose was 45-70 Gy (median 60 Gy). One hundred and thirty-two patients were treated with three-dimensional conformal radiotherapy(3DCRT) and 38 with two-dimensional radiotherapy(2DRT). Forty-one patients received radiotherapy alone, 78 received sequential chemoradiotherapy and 51 received concurrent chemoradiotherapy. Thirty-seven SNPs in 20 DNA repair genes were analyzed by using PCR- based restricted fragment length polymorphism (RFLP). These genes were apoptosis and inflammatory cytokine genes including ATM, ERCC1, XRCC3, XRCCI, XPD, XPC, XPG, NBS1, STK15, ZNF350, ADPRT, TP53, FAS, FASL, CYP2D6*4, CASPASE8, COX2,TGF-β, CD14 and ACE. The endpoint was grade ≥2 R I E. Results: Forty of the 170 patients developed grade ≥2 R I E, including 36 in grade 2 and 4 in grade 3. Univariate analysis revealed that radiation technique and concurrent chemoradiotherapy were statistically significant relatives to the incidence of R I E (P=0.032, 0.049), and both of them had the trend associating with the esophagitis (P=0.072, 0.094). An increased incidence of esophagitis was observed associating with the TGF-β 1 -509T and XPD 751Lys/Lys genotypes (χ 2 =5.65, P=0.017; χ 2 =3.84, P=0.048) in multivariate analysis. Conclusions: Genetic polymorphisms in TGF-β 1 gene and XPD gene have a significant association with radiation-induced esophagitis. (authors)

  20. Ion beam induced luminescence: Relevance to radiation induced bystander effects

    Science.gov (United States)

    Ahmad, S. B.; McNeill, F. E.; Byun, S. H.; Prestwich, W. V.; Seymour, C.; Mothersill, C. E.

    2012-10-01

    The aim of this work is quantify the light emitted as a result of charged particle interaction in materials which may be of relevance to radiation induced "bystander effects" studies. We have developed a system which employs single photon counting to measure the light emitted from samples irradiated under vacuum by a charged particle beam. The system uses a fast photomultiplier tube with a peak cathode response at 420 nm. It has been tested in a proof-of-principle experiment using polystyrene targets. Light output, as a result of irradiation, was measured. The luminescence yield appears to have a non-linear behavior with the incident ion fluence: it rises exponentially to an asymptotic value. The target was irradiated with beam energies varying from 1 to 2 MeV and showed saturation at or before an incident fluence rate of 3 × 1013 H+/cm2 s. The average saturation value for the photon output was found to be 40 × 106 cps. Some measurements were performed using filters to study the emission at specific wavelengths. In the case of filtered light measurements, the photon output was found to saturate at 28 × 103, 10 × 106, and 35 × 106 cps for wavelengths of 280 ± 5 nm, 320 ± 5 nm and 340 ± 5 nm respectively. The light output reaches a maximum value because of damage induced in the polymer. Our measurements indicate a "damage cross section" of the order of 10-14 cm2. The average radiant intensity was found to increase at wavelengths of 280 and 320 nm when the proton energy was increased. This was not found to occur at 340 nm. In conclusion, the light emission at specific wavelengths was found to depend upon the incident proton fluence and the proton energy. The wavelengths of the emitted light measured in this study have significance for the understanding of radiation induced bystander effects.

  1. Defense mechanisms against radiation induced teratogenic damage in mice

    International Nuclear Information System (INIS)

    Kato, F.; Ootsuyama, A.; Nomoto, S.; Norimura, T.

    2002-01-01

    Experimental studies with mice have established that fetuses at midgestational stage are highly susceptible to malformation at high, but not low, doses of radiation. When DNA damage is produced by a small amount of radiation, it is efficiently eliminated by DNA repair. However, DNA repair is not perfect. There must be defense mechanisms other than DNA repair. In order to elucidate the essential role of p53 gene in apoptotic tissue repair, we compared the incidence of radiation-induced malformations and deaths (deaths after day 10) in wild-type p53 (+/+) mice and null p53 (-/-) mice. For p53 (+/+) mice, an X-ray dose of 2 Gy given at a high dose-rate (450 mGy/min) to fetuses at 9.5 days of gestation was highly lethal and considerably teratogenic whereas it was only slightly lethal but highly teratogenic for p53 (-/-) fetuses. This reciprocal relationship of radiosensitivity to malformations and deaths supports the notion that fetal tissues have a p53 -dependent idguardianln of the tissue that aborts cells bearing radiation-induced teratogenic DNA damage. When an equal dose of 2 Gy given at a 400-fold lower dose-rate (1.2 mGy/min), this dose became not teratogenic for p53 (+/+) fetuses exhibiting p53 -dependent apoptosis, whereas this dose remained teratogenic for p53 (-/-) fetuses unable to carry out apoptosis. Furthermore, when the dose was divided into two equal dose fractions (1+1 Gy) at high dose rate, separated by 24 hours, the incidences of malformations were equal with control level for p53 (+/+), but higher for p53 (-/-) mice. Hence, complete elimination of teratogenic damage from irradiated tissues requires a concerted cooperation of two mechanisms; proficient DNA repair and p53-dependent apoptotic tissue repair

  2. Effect of salidroside on radiation-induced bone marrow adipogenesis

    International Nuclear Information System (INIS)

    Zhu Jincan; Chen Xiaoyu; Liu Chengcheng; Zhu Aizhen; Liu Shantao; Liu Gexiu

    2014-01-01

    Objective: To investigate the potential and underlying molecular mechanism of salidroside in ameliorating radiation-induced bone marrow adipogenesis and stimulating hematopoiesis. Methods: The female BALB/c mice aged 6-7 weeks were randomly divided into normal control group, radiation group and salidroside group. The radiation group and salidroside group were irradiated with 6.0 Gy of "6"0Co γ-rays. The salidroside group was intraperitoneally injected with 30 mg·kg"-"1·d"-"1 salidroside at 12 h and then every day until 8th d after radiation. The normal control group and radiation group were treated with equal volume of saline as control of salidroside. At 14 d after radiation, the mice weight, peripheral blood count, femur bone marrow histology, and the proportion of adipocyte area were measured, and the expressions of PPAR-γ and FABP4 were detected by q-PCR. Results: After irradiation, the numbers of white blood cells, hemoglobin and platelet in peripheral blood were reduced obviously, and the percentage of adipocyte area was increased significantly. Compared with mice in the radiation group, salidroside inhibited adipogenesis and reduced the proportion of adipocyte area (t = 13.31, P < 0.05) by reducing the expressions of PPAR-γ and FABP4 (t = 8.64, 13.19, P < 0.05). The number of white blood cells was partly recovered at 7 d after irradiation (t = 5.80, P < 0.05). Both white blood cells and hemoglobinin in peripheral blood of the salidroside group were higher than those in the radiation group at 14 d after irradiation. Conclusions: Salidroside could inhibit radiation-induced bone marrow adipogenesis and regulate bone marrow microenvironment, thereby promotes hematopoietic recovery in mice after radiation injury. (authors)

  3. Radiation-induced apoptosis of lymphocytes in peripheral blood

    International Nuclear Information System (INIS)

    Oh, Yoon Kyeong; Lee, Tae Bum; Nam, Taek Keun; Kee, Keun Hong; Choi, Cheol Hee

    2003-01-01

    This study quantitatively evaluated the apoptosis in human peripheral blood lymphocytes using flow cytometry, and investigated the possibility of using this method, with a small amount of blood, and the time and dose dependence of radiation-induced apoptosis. Peripheral blood lymphocytes were isolated from the heparinized venous blood of 11 healthy volunteers, 8 men and 3 women, with each 10 ml of blood being divided into 15 samples. The blood lymphocytes were irradiated using a linear accelerator at a dose rate of 2.4 Gy/min, to deliver doses of 0.5, 1, 2 and 5 Gy. The control samples, and irradiated cells, were maintained in culture medium for 24, 48 and 72 hours following the irradiation. The number of apoptotic cells after the in vitro X-irradiation was measured by flow cytometry after incubation periods of 24, 48 and 72 hours. We also observed the apoptotic cells using a DNA fragmentation assay and electron microscopy. The rate of spontaneous apoptosis increased in relation to the time interval following irradiation (1.761±0.161, 3.563±0.564, 11.098±2.849, at 24, 48, and 72 hours). The apoptotic cells also increased in the samples irradiated with 0.5, 1, 2 and 5 Gy, in a radiation dose and time interval after irradiation manner, with the apoptosis being too great at 72 hours after irradiation. The dose-response curves were characterized by an initial steep increase in the number of apoptotic cells for irradiation doses below 2 Gy, with a flattening of the curves as the dose approached towards 5 Gy. The flow cytometric assay technique yielded adequate data, and required less than 1 mL of blood. The time and dose dependence of the radiation-induced apoptosis, was also shown. It is suggested that the adequate time interval required for the evaluation of apoptosis would be 24 to 48 hours after blood sampling

  4. Radiation-induced brachial plexus neuropathy in breast cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, N.K.; Pfeiffer, P.; Mondrup, K.; Rose, C. (Odense Univ. Hospital (Denmark). Dept. of Neurology Odense Univ. Hospital (Denmark). Dept. of Clinical Neurophysiology Odense Univ. Hospital (Denmark). Dept. of Oncology R)

    1990-01-01

    The incidence and latency period of radiation-induced brachial plexopathy (RBP) were assessed in 79 breast cancer patients by a neurological follow-up examination at least 60 months (range 67-130 months) after the primary treatment. All patients were treated primarily with simple mastectomy, axillary nodal sampling and radiotherapy (RT). Postoperatively, pre- and postmenopausal patients were randomly allocated chemotherapy for antiestrogen treatment. All patients were recurrence-free at time of examination. Clinically, 35% (25-47%) of the patients had RBP; 19% (11-29%) had definite RBP, i.e. were physically disabled, and 16% (9-26%) had probable RBP. Fifty percent (31-69%) had affection of the entire plexus, 18% (7-35%) of the upper trunk only, and 4% (1-18%) of the lower trunk. In 28% (14-48%) of cases assessment of a definite level was not possible. RBP was more common after radiotherapy and chemotherapy (42%) than after radiotherapy alone (26%) but the difference was not statistically significant (p = 0.10). The incidence of definite RBP was significantly higher in the younger age group (p = 0.02). This could be due to more extensive axillary surgery but also to the fact that chemotherapy was given to most premenopausal patients. In most patients with RBP the symptoms began during or immediately after radiotherapy, and were thus without significant latency. Chemotherapy might enhance the radiation-induced effect on nerve tissue, thus diminishing the latency period. Lymphedema was present in 22% (14-32%), especially in the older patients, and not associated with the development of RBP. In conclusion, the damaging effect of RT on peripheral nerve tissue was documented. Since no successful treatment is available, restricted use of RT to the brachial plexus is warranted, especially when administered concomitantly with cytotoxic therapy. (orig.).

  5. Genetic analysis of radiation-induced mouse thymic lymphomas

    International Nuclear Information System (INIS)

    Kominami, R.; Wakabayashi, Y.; Niwa, O.

    2003-01-01

    Mouse thymic lymphomas are one of the classic models of radiation-induced malignancies, and the model has been used for the study of genes involved in carcinogenesis. ras oncogenes are the first isolate which undergoes mutations in 10 to 30 % of lymphomas, and p16INK4a and p19ARF in the INK4a-ARF locus are also frequently inactivated. In our previous study, the inactivation of Ikaros, a key regurator of lymphoid system, was found in those lymphomas, and it was suggested that there are other responsible genes yet to be discovered. On the other hand, genetic predisposition to radiation-induced lymphoma often differs in different strains, and this reflects the presence of low penetrance genes that can modify the impact of a given mutation. Little study of such modifiers or susceptibility genes has been performed, either. Recent availability of databases on mouse genome information and the power of mouse genetic system underline usefulness of the lymphoma model in search for novel genes involved, which may provide clues to molecular mechanisms of development of the radiogenic lymphoma and also genes involved in human lymphomas and other malignancies. Accordingly, we have carried out positional cloning for the two different types of tumor-related genes. In this symposium, our current progress is presented that includes genetic mapping of susceptibility/ resistance loci on mouse chromosomes 4, 5 and 19, and also functional analysis of a novel tumor suppressor gene, Rit1/Bcl11b, that has been isolated from allelic loss (LOH) mapping and sequence analysis for γ -ray induced mouse thymic lymphomas

  6. Radiation induces aerobic glycolysis through reactive oxygen species

    International Nuclear Information System (INIS)

    Zhong, Jim; Rajaram, Narasimhan; Brizel, David M.; Frees, Amy E.; Ramanujam, Nirmala; Batinic-Haberle, Ines; Dewhirst, Mark W.

    2013-01-01

    Background and purpose: Although radiation induced reoxygenation has been thought to increase radiosensitivity, we have shown that its associated oxidative stress can have radioprotective effects, including stabilization of the transcription factor hypoxia inducible factor 1 (HIF-1). HIF-1 is known to regulate many of the glycolytic enzymes, thereby promoting aerobic glycolysis, which is known to promote treatment resistance. Thus, we hypothesized that reoxygenation after radiation would increase glycolysis. We previously showed that blockade of oxidative stress using a superoxide dismutase (SOD) mimic during reoxygenation can downregulate HIF-1 activity. Here we tested whether concurrent use of this drug with radiotherapy would reduce the switch to a glycolytic phenotype. Materials and methods: 40 mice with skin fold window chambers implanted with 4T1 mammary carcinomas were randomized into (1) no treatment, (2) radiation alone, (3) SOD mimic alone, and (4) SOD mimic with concurrent radiation. All mice were imaged on the ninth day following tumor implantation (30 h following radiation treatment) following injection of a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Hemoglobin saturation was measured by using hyperspectral imaging to quantify oxygenation state. Results: Mice treated with radiation showed significantly higher 2-NBDG fluorescence compared to controls (p = 0.007). Hemoglobin saturation analysis demonstrated reoxygenation following radiation, coinciding with the observed increase in glycolysis. The concurrent use of the SOD mimic with radiation demonstrated a significant reduction in 2-NBDG fluorescence compared to effects seen after radiation alone, while having no effect on reoxygenation. Conclusions: Radiation induces an increase in tumor glucose demand approximately 30 h following therapy during reoxygenation. The use of an SOD mimic can prevent the increase in aerobic glycolysis when used

  7. Effect of small dose of radiation on induction of apoptosis in murine tumors

    International Nuclear Information System (INIS)

    Seong, Jin Sil; Pyo, Hong Ryull; Chung, Eun Ji; Kim, Sung Hee; Suh, Chang Ok

    1999-01-01

    To investigate the presence of adaptive response by low dose radiation in murine tumors in relation to radiation induced apoptosis as well as related mechanism. Syngeneic murine tumors, OCa-1 and HCa-l, were given 0.05 Gy pretreatment followed by therapeutic dose of 25 Gy radiation. Induction of apoptosis was analyzed for each treatment group. Regulating molecules of apoptosis. p53, Bcl-2, Sax, Bel-X, were also analyzed by Western blotting. In 0.05 Gy pretreatment group of OCa-l, 25 Gy-induced apoptosis per 1000 cells was 229, which was estimated at 30% lower level than the expected (p<0.05). In contrast, this reduction in radiation induced apoptosis was not seen in HCa-1. In the expression of apoptosis regulating molecules, p53 increased in both tumors in response to radiation. Bcl-2 and Bax did not show significant change in both tumors however, the expression of Bcl-2 surpassed that of Bax in 0.05 Gy pretreatment group of OCa-1. Bcl-X was not expressed in OCa-1. In HCa-l, ScI-X showed increased expression even with 0.05 Gy. Adaptive response by low dose radiation is shown in one murine tumor, OCa-I, in relation to radiation induced apoptosis. Apoptosis regulating molecules including Bcl-2/Bax and Bcl-X, appear to related. This study shows an evidence that adaptive response is present, but not a generalized phenomenon in vivo

  8. Radiation-induced signaling results in mitochondrial impairment in mouse heart at 4 weeks after exposure to X-rays.

    Science.gov (United States)

    Barjaktarovic, Zarko; Schmaltz, Dominik; Shyla, Alena; Azimzadeh, Omid; Schulz, Sabine; Haagen, Julia; Dörr, Wolfgang; Sarioglu, Hakan; Schäfer, Alexander; Atkinson, Michael J; Zischka, Hans; Tapio, Soile

    2011-01-01

    Radiation therapy treatment of breast cancer, Hodgkin's disease or childhood cancers expose the heart to high local radiation doses, causing an increased risk of cardiovascular disease in the survivors decades after the treatment. The mechanisms that underlie the radiation damage remain poorly understood so far. Previous data show that impairment of mitochondrial oxidative metabolism is directly linked to the development of cardiovascular disease. In this study, the radiation-induced in vivo effects on cardiac mitochondrial proteome and function were investigated. C57BL/6N mice were exposed to local irradiation of the heart with doses of 0.2 Gy or 2 Gy (X-ray, 200 kV) at the age of eight weeks, the control mice were sham-irradiated. After four weeks the cardiac mitochondria were isolated and tested for proteomic and functional alterations. Two complementary proteomics approaches using both peptide and protein quantification strategies showed radiation-induced deregulation of 25 proteins in total. Three main biological categories were affected: the oxidative phophorylation, the pyruvate metabolism, and the cytoskeletal structure. The mitochondria exposed to high-dose irradiation showed functional impairment reflected as partial deactivation of Complex I (32%) and Complex III (11%), decreased succinate-driven respiratory capacity (13%), increased level of reactive oxygen species and enhanced oxidation of mitochondrial proteins. The changes in the pyruvate metabolism and structural proteins were seen with both low and high radiation doses. This is the first study showing the biological alterations in the murine heart mitochondria several weeks after the exposure to low- and high-dose of ionizing radiation. Our results show that doses, equivalent to a single dose in radiotherapy, cause long-lasting changes in mitochondrial oxidative metabolism and mitochondria-associated cytoskeleton. This prompts us to propose that these first pathological changes lead to an increased

  9. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    Energy Technology Data Exchange (ETDEWEB)

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R., E-mail: akennedy@mail.med.upenn.edu

    2014-03-15

    Purpose: The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events, as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials: Ferrets were exposed to 0 to 2 Gy of whole-body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results: The lethal dose of radiation to 50% of the population (LD{sub 50}) of the ferrets was established at ∼1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 postirradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early time points postirradiation when coagulopathies were present and becoming progressively more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions: Data presented here provide evidence that death at the LD{sub 50} in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is due solely to the cell-killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals.

  10. Involvement of prostaglandins and histamine in radiation-induced temperature responses in rats

    International Nuclear Information System (INIS)

    Kandasamy, S.B.; Hunt, W.A.

    1990-01-01

    Exposure of rats to 1-15 Gy of gamma radiation induced hyperthermia, whereas exposure to 20-150 Gy produced hypothermia. Since radiation exposure induced the release of prostaglandins (PGs) and histamine, the role of PGs and histamine in radiation-induced temperature changes was examined. Radiation-induced hyper- and hypothermia were antagonized by pretreatment with indomethacin, a cyclooxygenase inhibitor. Intracerebroventricular administration of PGE2 and PGD2 induced hyper- and hypothermia, respectively. Administration of SC-19220, a specific PGE2 antagonist, attenuated PGE2- and radiation-induced hyperthermia, but it did not antagonize PGD2- or radiation-induced hypothermia. Consistent with an apparent role of histamine in hypothermia, administration of disodium cromoglycate (a mast cell stabilizer), mepyramine (H1-receptor antagonist), or cimetidine (H2-receptor antagonist) attenuated PGD2- and radiation-induced hypothermia. These results suggest that radiation-induced hyperthermia is mediated via PGE2 and that radiation-induced hypothermia is mediated by another PG, possibly PGD2, via histamine

  11. The effect of ethanol on the γ radiation induced polymerization of styrene

    International Nuclear Information System (INIS)

    Zhang Xujia; Ha Hongfei; Wu Jilan

    1990-01-01

    The γ radiation induced polymerization of styrene in the presence of ethanol was studied at dose rate of 5 x 10 17 eV/ml min. The result showed that the radiation induced polymerization of styrene was sensitized by ethanol. The experimental results were in agreement with the theoretical calculation of WAS equation. The mechanism of sensitization was proposed as proton transfer reaction

  12. Radiation-Induced Changes in Normal-Appearing White Matter in Patients With Cerebral Tumors: A Diffusion Tensor Imaging Study

    International Nuclear Information System (INIS)

    Nagesh, Vijaya; Tsien, Christina I.; Chenevert, Thomas L.; Ross, Brian D.; Lawrence, Theodore S.; Junick, Larry; Cao Yue

    2008-01-01

    Purpose: To quantify the radiation-induced changes in normal-appearing white matter before, during, and after radiotherapy (RT) in cerebral tumor patients. Methods and Materials: Twenty-five patients with low-grade glioma, high-grade glioma, or benign tumor treated with RT were studied using diffusion tensor magnetic resonance imaging. The biologically corrected doses ranged from 50 to 81 Gy. The temporal changes were assessed before, during, and to 45 weeks after the start of RT. The mean diffusivity of water ( ), fractional anisotropy of diffusion, diffusivity perpendicular (λ perpendicular ) and parallel (λ parallel ) to white matter fibers were calculated in normal-appearing genu and splenium of the corpus callosum. Results: In the genu and splenium, fractional anisotropy decreased and , λ parallel , λ -perpendicular increased linearly and significantly with time (p -perpendicular had increased ∼30% in the genu and splenium, and λ parallel had increased 5% in the genu and 9% in the splenium, suggesting that demyelination is predominant. The increases in λ perpendicular and λ parallel were dose dependent, starting at 3 weeks and continuing to 32 weeks from the start of RT. The dose-dependent increase in λ perpendicular and λ parallel was not sustained after 32 weeks, indicating the transition from focal to diffuse effects. Conclusion: The acute and subacute changes in normal-appearing white matter fibers indicate radiation-induced demyelination and mild structural degradation of axonal fibers. The structural changes after RT are progressive, with early dose-dependent demyelination and subsequent diffuse dose-independent demyelination and mild axonal degradation. Diffusion tensor magnetic resonance imaging is potentially a biomarker for the assessment of radiation-induced white matter injury

  13. Use of Human Cadaveric Mesenchymal Stem Cells for Cell Therapy of a Chronic Radiation-Induced Skin Lesion: A Case Report

    International Nuclear Information System (INIS)

    Portas, M.; Coppola, A.; Mansilla, E.; Drago, H.; Dubner, D.; Radl, A.; Di Giorgio, M.

    2016-01-01

    Acute and late radiation-induced injury on skin and subcutaneous tissues are associated with substantial morbidity in radiation therapy, interventional procedures and also are of concern in the context of nuclear or radiological accidents. Pathogenesis is initiated by depletion of acutely responding epithelial tissues and damage to vascular endothelial micro-vessels. Efforts for medical management of severe radiation-induced lesions have been made. Nevertheless, the development of strategies to promote wound healing, including stem cell therapy, is required. From 1997 to 2014, over 248 patients were referred to the Radio-pathology Committee of Hospital de Quemados del Gobierno de la Ciudad de Buenos Aires (Burns Hospital) for the diagnosis and therapy of radiation-induced localized lesions. As part of the strategies for the management of severe cases, there is an ongoing research and development protocol on 'Translational Clinical Trial phases I/II to evaluate the safety and efficacy of adult mesenchymal stem cells from bone marrow for the treatment of large burns and radiological lesions'. The object of this work was to describe the actions carried out by the Radio-pathology Committee of the Burns Hospital in a chronic case with more than 30 years of evolution without positive response to conventional treatments. The approach involved the evaluation of the tissular compromise of the lesion, the prognosis and the personalized treatment, including regenerative therapy. (authors)

  14. Use of Human Cadaveric Mesenchymal Stem Cells for Cell Therapy of a Chronic Radiation-Induced Skin Lesion: A Case Report.

    Science.gov (United States)

    Portas, M; Mansilla, E; Drago, H; Dubner, D; Radl, A; Coppola, A; Di Giorgio, M

    2016-09-01

    Acute and late radiation-induced injury on skin and subcutaneous tissues are associated with substantial morbidity in radiation therapy, interventional procedures and also are of concern in the context of nuclear or radiological accidents. Pathogenesis is initiated by depletio