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Sample records for accidental radiation-induced hematopoietic

  1. Therapeutic strategies for the treatment of accidental radiation-induced hematopoietic syndrome

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    Bertho, J.M.; Frick, J.; Demarquay, C.; Prat, M.; Dudoignon, N.; Thierry, D.; Gourmelon, P. [Institut de Radioprotection et de Surete Nucleaire (IRSN) DRPH/SRBE, LTCRA, 92 - Fontenay aux Roses (France)

    2006-07-01

    The hematopoietic syndrome induced by large field high dose accidental irradiation remains difficult to treat, mainly due to the heterogeneity of irradiation. As a result, there always remains an area of active hematopoiesis that was partly protected from irradiation. The choice of a therapeutic strategy thus must be based upon the estimate of radiation damage to the bone marrow. This can be achieved by the use of biological indicators of damage to specific organs. With this respect, we recently showed that the follow up of Flt3 ligand concentration in the blood allowed a direct evaluation of residual hematopoiesis soon after irradiation in animal models as well as in humans. Nevertheless, the possible therapeutic strategies available for the treatment of radiation-induced hematopoietic syndrome are limited to the choice between either stem cell transplantation or supportive care. Recently, the use of autologous cell therapy was proposed. The principle is to harvest the hematopoietic cells surviving to irradiation, to expand these cells in vitro and to re inject these cells to the patient. This is based upon the existence of a residual hematopoiesis and on the possibility to expand in vitro irradiated hematopoietic cells. Experimental work in a non human primate model of high-dose, heterogeneous irradiation showed that it was possible to harvest surviving hematopoietic cells after irradiation and to amplify these cells in vitro. However, the therapeutic efficiency of the reinjected cells was limited by the occurrence of a combined disease, implicating the lungs, the kidney and the liver, but also a severe vascular damage. Such a multiple organ disease syndrome induced by ionizing radiations was already observed in two radiation accidents, the Tokai MURA accident and the Neshvish accident. In an attempt to accelerate the hematopoietic recovery, we combined autologous cell therapy with G-CSF injections in the same model of heterogeneous irradiation with non human

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

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    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.

  3. Mitigation of radiation induced hematopoietic injury via regulation of Nrf-2 and increasing hematopoietic stem cells

    International Nuclear Information System (INIS)

    Patwardhan, R.S.; Sharma, Deepak; Checker, Rahul; Santosh Kumar, S.

    2014-01-01

    Therapeutic doses of ionizing radiation (IR) that can be delivered to tumors are restricted due to radiation induced damage to surrounding normal tissues thereby limiting the effectiveness of radiotherapy. Strategies to develop agents that selectively protect normal cells yielded limited success in the past. There is pressing need to develop safe, syndrome specific and effective radiation countermeasures to prevent or mitigate the harmful consequences of radiation exposure. Survival of bone marrow stem cells (HSCs) play a key role in protecting against IR induced hematopoietic injury. Many studies have shown manipulation of HSC frequency and/or survival as principal mechanism of radioprotection. It is known that, Nrf-2 plays crucial role in HSC survival and maintenance under oxidative stress conditions. In the present study, we have investigated the radioprotective ability of a flavonoid baicalein (5,6,7-trihydroxyflavone), extracted from the root of Scutellaria baicalensis Georgi, a medicinal plant traditionally used in Oriental medicine. There are numerous reports showing anti-inflammatory, anti-apoptotic, anti-oxidant, anti-cancer, anti-microbial, anti-mutagenic and neuroprotective properties of baicalein. Based on these reports, we have investigated the ability of baicalein to protect against radiation induced hematopoietic injury. Baicalein administration to mice protected against WBI induced mortality. Interestingly, the stem cell frequency increased in bone marrow cells obtained from baicalein administered mice as compared to vehicle treated mice. Baicalein treatment led to increased phospho-Nrf-2 levels in lineage negative BM-MNC. Administration of mice with Nrf-2 inhibitor prior to baicalein treatment led to significant abrogation of radioprotective ability of baicalein. This result suggests that, Nrf-2 may be playing a key role in baicalein mediated radioprotection. Here, we have shown that baicalein administration augments stem cell frequency, induces

  4. Ionizing radiation induces apoptosis in hematopoietic stem and progenitor cells

    International Nuclear Information System (INIS)

    Meng, A.; Zhou, D.; Geiger, H.; Zant, G.V.

    2003-01-01

    The aims of this study was to determine if ionizing radiation (IR) induces apoptosis in hematopoietic stem (HSC) and progenitor cells. Lin-cells were isolated from mouse bone marrow (BM) and pretreated with vehicle or 100 μM z-VAD 1 h prior to exposure to 4 Gy IR. The apoptotic and/or necrotic responses of these cells to IR were analyzed by measuring the annexin V and/or 7-AAD staining in HSC and progenitor populations using flow cytometry, and hematopoietic function of these cells was determined by CAFC assay. Exposure of Lin-cells to IR selectively decreased the numbers of HSC and progenitors in association with an increase in apoptosis in a time-dependent manner. Pretreatment of Lin- cells with z-VAD significantly inhibited IR-induced apoptosis and the decrease in the numbers of HSC and progenitors. However, IR alone or in combination with z-VAD did not lead to a significant increase in necrotic cell death in either HSC or progenitors. In addition, pretreatment of BM cells with z-VAD significantly attenuated IR-induced reduction in the frequencies of day-7, -28 and -35 CAFC. Exposure of HSC and progenitors to IR induces apoptosis. The induction of HSC and progenitor apoptosis contributes to IR-induced suppression of their hematopoietic function

  5. Administration of interleukin-6 stimulates multilineage hematopoiesis and accelerates recovery from radiation-induced hematopoietic depression

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    Patchen, M.L.; MacVittie, T.J.; Williams, J.L.; Schwartz, G.N.; Souza, L.M. (Armed Forces Radiobiology Research Institute, Bethesda, MD (USA))

    1991-02-01

    Hematopoietic depression and subsequent susceptibility to potentially lethal opportunistic infections are well-documented phenomena following radiotherapy. Methods to therapeutically mitigate radiation-induced myelosuppression could offer great clinical value. In vivo studies have demonstrated that interleukin-6 (IL-6) stimulates pluripotent hematopoietic stem cell (CFU-s), granulocyte-macrophage progenitor cell (GM-CFC), and erythroid progenitor cell (CFU-e) proliferation in normal mice. Based on these results, the ability of IL-6 to stimulate hematopoietic regeneration following radiation-induced hematopoietic injury was also evaluated. C3H/HeN female mice were exposed to 6.5 Gy 60Co radiation and subcutaneously administered either saline or IL-6 on days 1 through 3 or 1 through 6 postexposure. On days 7, 10, 14, 17, and 22, femoral and splenic CFU-s, GM-CFC, and CFU-e contents and peripheral blood white cell, red cell, and platelet counts were determined. Compared with saline treatment, both 3-day and 6-day IL-6 treatments accelerated hematopoietic recovery; 6-day treatment produced the greater effects. For example, compared with normal control values (N), femoral and splenic CFU-s numbers in IL-6-treated mice 17 days postirradiation were 27% N and 136% N versus 2% N and 10% N in saline-treated mice. At the same time, bone marrow and splenic GM-CFC values were 58% N and 473% N versus 6% N and 196% N in saline-treated mice; bone marrow and splenic CFU-e numbers were 91% N and 250% N versus 31% N and 130% N in saline-treated mice; and peripheral blood white cell, red cell, and platelet values were 210% N, 60% N, and 24% N versus 18% N, 39% N, and 7% N in saline-treated mice. These studies demonstrate that therapeutically administered IL-6 can effectively accelerate multilineage hematopoietic recovery following radiation-induced hematopoietic injury.

  6. 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

  7. Mitigation of radiation-induced hematopoietic injury via regulation of cellular MAPK/phosphatase levels and increasing hematopoietic stem cells.

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    Patwardhan, R S; Sharma, Deepak; Checker, Rahul; Sandur, Santosh K

    2014-03-01

    Here we describe a novel strategy for mitigation of ionizing radiation-induced hematopoietic syndrome by suppressing the activity of MKP3, resulting in ERK activation and enhanced abundance of hematopoietic stem cells, using the antioxidant flavonoid baicalein (5,6,7-trihydroxyflavone). It offered complete protection to mouse splenic lymphocytes against radiation-induced cell death. Inhibitors of ERK and Nrf-2 could significantly abrogate baicalein-mediated radioprotection in lymphocytes. Baicalein inhibited phosphatase MKP3 and thereby enhanced phosphorylation of ERK and its downstream proteins such as Elk and Nrf-2. It also increased the nuclear levels of Nrf-2 and the mRNA levels of its dependent genes. Importantly, baicalein administration to mice before radiation exposure led to significant recovery of loss of bone marrow cellularity and also inhibited cell death. Administration of baicalein increased the hematopoietic stem cell frequency as measured by side-population assay and also by antibody staining. Further, baicalein offered significant protection against whole-body irradiation (WBI; 7.5Gy)-induced mortality in mice. Interestingly, we found that baicalein works by activating the same target molecules ERK and Nrf-2 both in vitro and in vivo. Finally, administration of all-trans-retinoic acid (inhibitor of Nrf-2) significantly abrogated baicalein-mediated protection against WBI-induced mortality in mice. Thus, in contrast to the generalized conception of antioxidants acting as radioprotectors, we provide a rationale that antioxidants exhibit pleiotropic effects through the activation of multiple cellular signaling pathways. © 2013 Elsevier Inc. All rights reserved.

  8. Therapeutic approaches of hematopoietic syndrome after serious accidental global irradiation. Ex vivo expansion interest of hematopoietic cells

    International Nuclear Information System (INIS)

    Thierry, D.

    1994-01-01

    Aplasia is one of the main syndrome, appearing after one global accidental irradiation by one ionizing radiation source. The hematopoietic syndrome is characterized by a peripheric blood cell number fall; the cell marrow is reduced too

  9. Protective effects of parathyroid hormone on radiation-induced hematopoietic damage in mice

    International Nuclear Information System (INIS)

    Feng Xiaoqing; Hu Zhiyong; Liu Huaqing; Ding Xiaofei; Li Bingyan; Zhang Zengli

    2011-01-01

    Objective: To study the protective effects of parathyroid hormone (PTH) on radiation-induced hematopoietic damage in mice. Methods: A total of sixty male C57 mice were irradiated by 60 Co γ-rays to induce hematopoietic injuries, and then the mice were randomly divided into PTH and control group.The PTH-treated group was treated with PTH (80 μg· kg -1 · d -1 ) intraperitoneally everyday. The control group was given equivalent volume saline. Peripheral blood cell number, bone marrow mononuclear cell number,granulocyte-macrophage colony forming units (CFU-GM) and CD34 positive cells in bone marrow were detected. Results: With the whole post-irradiation period, the WBC and bone marrow mononuclear cell numbers in PTH-treated mice were significantly higher than those in saline-treated mice (t=6.32, 9.19, 11.18, 7.44 and 4.42, P<0.05). The RBC numbers in PTH-treated mice were significantly higher than those in control mice at 10 d, 15 d and 20 d post-irradiation (t =6.48, 3.66 and 4.98, P<0.05). The PLT numbers in PTH-treated mice were significantly higher than those in control group at 5 and 30 d post-irradiation (t=2.57 and 3.10, P<0.05). PTH increased CD34 positive cell and CFU-GM numbers in bone marrow after irradiation (t=16.12, 7.82 and 20.00, P<0.05). Conclusions: PTH could improve the hematopoietic recovery after irradiation. (authors)

  10. Indications of hematopoietic stem cell transplantations and therapeutic strategies of accidental irradiations

    International Nuclear Information System (INIS)

    2003-01-01

    Produced by a group of experts, this document first discusses the issue of accidental irradiations in terms of medical management. They notably outline the peculiar characteristics of these irradiations with respect to therapeutic irradiations. They agreed on general principles regarding casualty sorting criteria and process, and their medical treatment (systematic hematopoiesis stimulation, allogeneic transplantation of hematopoietic stem cells). They discuss some practical aspects of these issues: casualty sorting within a therapeutic perspective (actions to be performed within 48 hours), therapeutic strategies (support therapy, use of cytokines, and therapy by hematopoietic stem cell transplant). They state a set of recommendations regarding the taking into care and diagnosis, therapeutic strategies, research perspectives, and teaching

  11. Rapid detection of radiation-induced chromosomal aberrations in lymphocytes and hematopoietic progenitor cells by mFISH

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    Greulich, K.M.; Rhein, A.P.; Brueckner, M.; Molls, M. [Department of Radiation Oncology, Technical University of Munich, Ismaninger Strasse 22, D-81675 Munich (Germany); Kreja, L. [Institute for Occupational, Social and Environmental Medicine, University of Ulm, Ulm (Germany); Heinze, B. [Department of Medical Genetics, University of Ulm, Ulm (Germany); Weier, H.-U.G. [Life Sciences Division, E.O. Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Fuchs, P. [Vysis GmbH, Bergisch-Gladbach (Germany)

    2000-07-20

    Structural chromosome aberrations (SCAs) are sensitive indicators of a preceding exposure of the hematopoietic system to ionizing radiation. Cytogenetic investigations have therefore become routine tools for an assessment of absorbed radiation doses and their biological effects after occupational exposure or radiation accidents. Due to its speed and ease of use, fluorescence in situ hybridization (FISH) with whole chromosome painting (WCP) probes has become a method of choice to visualize SCAs. Until recently, this technique was limited to a rather small number of chromosomes, which could be tested simultaneously. As a result, only a fraction of the structural aberrations present in a sample could be detected and the overall dose effect had to be calculated by extrapolation. The recent introduction of two genome-wide screening techniques in tumor research, i.e., Spectral Karyotyping (SKY) and multicolor FISH (mFISH) now allows the detection of translocations involving any two non-homologous chromosomes. The present study was prompted by our desire to bring the power of mFISH to bear for the rapid identification of radiation-induced SCAs. We chose two model systems to investigate the utility of mFISH: lymphocytes that were exposed in vitro to 3 Gy photons and single hematopoietic progenitor cell colonies isolated from a Chernobyl victim 9 years after in vivo exposure to 5.4 Sv. In lymphocytes, we found up to 15 different chromosomes involved in rearrangements indicating complex radiation effects. Stable aberrations detected in hematopoietic cell colonies, on the other hand, showed involvement of up to three different chromosomes. These results demonstrated that mFISH is a rapid and powerful approach to detect and characterize radiation-induced SCAs in the hemopoietic system. The application of mFISH is expected to result in a more detailed and, thus, more informative picture of radiation effects. Eventually, this technique will allow researchers to rapidly delineate

  12. Rutin-Enriched Extract from Coriandrum sativum L. Ameliorates Ionizing Radiation-Induced Hematopoietic Injury.

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    Han, Xiaodan; Xue, Xiaolei; Zhao, Yu; Li, Yuan; Liu, Weili; Zhang, Junling; Fan, Saijun

    2017-04-29

    Hematopoietic injury is a major cause of mortality in radiation accidents and a primary side effect in patients undergoing radiotherapy. Ionizing radiation (IR)-induced myelosuppression is largely attributed to the injury of hematopoietic stem and progenitor cells (HSPCs). Coriander is a culinary herb with multiple pharmacological effects and has been widely used in traditional medicine. In this study, flavonoids were identified as the main component of coriander extract with rutin being the leading compound (rutin-enriched coriander extract; RE-CE). We evaluated the radioprotective effect of RE-CE against IR-induced HSPCs injury. Results showed that RE-CE treatment markedly improved survival, ameliorated organ injuries and myelosuppression, elevated HSPCs frequency, and promoted differentiation and proliferation of HSPCs in irradiated mice. The protective role of RE-CE in hematopoietic injury is probably attributed to its anti-apoptotic and anti-DNA damage effect in irradiated HSPCs. Moreover, these changes were associated with reduced reactive oxygen species (ROS) and enhanced antioxidant enzymatic activities in irradiated HSPCs. Collectively, these findings demonstrate that RE-CE is able to ameliorate IR-induced hematopoietic injury partly by reducing IR-induced oxidative stress.

  13. Umbelliferone suppresses radiation induced DNA damage and apoptosis in hematopoietic cells of mice

    International Nuclear Information System (INIS)

    Jayakumar, S.; Bhilwade, H.N.; Chaubey, R.C.

    2012-01-01

    Radiotherapy is one of the major modes of treatment for different types of cancers. But the success of radiotherapy is limited by injury to the normal cells. Protection of the normal cells from radiation damage by radioprotectors can increase therapeutic efficiency. These radioprotectors can also be used during nuclear emergency situations. Umbelliferone (UMB) is a wide spread natural product of the coumarin family. It occurs in many plants from the Apiaceae family. In the present study radioprotective effect of UMB was investigated in vitro and in vivo. Anti genotoxic effect of Umbelliferone was tested by treating the splenic lymphocytes with various doses of UMB (6.5 μM - 50 μM) prior to radiation (6Gy) exposure. After the radiation exposure, extent of DNA damage was assessed by comet assay at 5 mm and two hours after radiation exposure. At both the time points, it was observed that the pretreatment of UMB reduced the radiation induced DNA damage to a significant extent in comparison to radiation control. UMB pretreatment also significantly reduced the radiation induced apoptosis enumerated by propidium iodide staining assay. Results of clonogenic survival assay using intestinal cell line showed that pretreatment with UMB significantly protected against radiation induced loss of colony forming units. To assess the anti genotoxic role of umbelliferone in vivo two different doses of UMB (20 mg/Kg and 40 mg/Kg of body weight) were injected into Swiss mice or with vehicle and exposed to radiation. Thirty minutes after the radiation comet assay was performed in peripheral leukocytes. Frequency of micro nucleated erythrocytes was scored in bone marrow cells. It was observed that UMB alone did not cause any significant increase in DNA damage in comparison to control. Animals which are exposed to radiation alone showed significant increase in DNA damage and micronuclei frequency. But animals treated with UMB prior to the radiation exposure showed significant decrease

  14. Catalase inhibits ionizing radiation-induced apoptosis in hematopoietic stem and progenitor cells.

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    Xiao, Xia; Luo, Hongmei; Vanek, Kenneth N; LaRue, Amanda C; Schulte, Bradley A; Wang, Gavin Y

    2015-06-01

    Hematologic toxicity is a major cause of mortality in radiation emergency scenarios and a primary side effect concern in patients undergoing chemo-radiotherapy. Therefore, there is a critical need for the development of novel and more effective approaches to manage this side effect. Catalase is a potent antioxidant enzyme that coverts hydrogen peroxide into hydrogen and water. In this study, we evaluated the efficacy of catalase as a protectant against ionizing radiation (IR)-induced toxicity in hematopoietic stem and progenitor cells (HSPCs). The results revealed that catalase treatment markedly inhibits IR-induced apoptosis in murine hematopoietic stem cells and hematopoietic progenitor cells. Subsequent colony-forming cell and cobble-stone area-forming cell assays showed that catalase-treated HSPCs can not only survive irradiation-induced apoptosis but also have higher clonogenic capacity, compared with vehicle-treated cells. Moreover, transplantation of catalase-treated irradiated HSPCs results in high levels of multi-lineage and long-term engraftments, whereas vehicle-treated irradiated HSPCs exhibit very limited hematopoiesis reconstituting capacity. Mechanistically, catalase treatment attenuates IR-induced DNA double-strand breaks and inhibits reactive oxygen species. Unexpectedly, we found that the radioprotective effect of catalase is associated with activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway and pharmacological inhibition of STAT3 abolishes the protective activity of catalase, suggesting that catalase may protect HSPCs against IR-induced toxicity via promoting STAT3 activation. Collectively, these results demonstrate a previously unrecognized mechanism by which catalase inhibits IR-induced DNA damage and apoptosis in HSPCs.

  15. The hematopoietic syndrome induced by an accidental radiation: evaluation and treatments; Le syndrome h atopoietique induit par une irradiation accidentelle: evaluation et traitements possibles

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    Bertho, J.M. [Institut de Radioprotection et de Surete Nucleaire (IRSN/DRPH/SRBE), Lab. de Therapie Cellulaire et de Radioprotection Accidentelle 92 - Fontenay-aux-Roses (France)

    2006-04-15

    The accidental radiation-induced hematopoietic syndrome remains difficult to treat, mainly due to the heterogeneity of irradiation. As a result, there always remains an area of active hematopoiesis that was partly protected from irradiation. The choice of a therapeutic strategy must be based upon the estimate of radiation damage to the bone marrow. This can be achieved by the use of biological indicators of radiation dose or damage such as the follow up of Flt3 ligand concentration in the blood. The possible therapeutic strategies remain limited, either stem cell transplantation or supportive care. A new approach based upon autologous cell therapy was proposed and the results highlighted new insight about the radiation-induced multiple organ disease syndrome. Other recent results from our lab suggested that among the possible therapeutic strategies, the stimulation of residual hematopoiesis by the mean of cytokines such as G-CSF is one of the most interesting strategies. These new data highlight the notion of residual hematopoiesis but also the fact that regulation mechanisms of residual hematopoiesis are not well understood. (author)

  16. Protection of Radiation-Induced Damage to the Hematopoietic System, Small Intestine and Salivary Glands in Rats by JNJ7777120 Compound, a Histamine H4 Ligand

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    Martinel Lamas, Diego J.; Carabajal, Eliana; Prestifilippo, Juan P.; Rossi, Luis; Elverdin, Juan C.; Merani, Susana; Bergoc, Rosa M.; Rivera, Elena S.; Medina, Vanina A.

    2013-01-01

    Based on previous data on the histamine radioprotective effect on highly radiosensitive tissues, in the present work we aimed at investigating the radioprotective potential of the H4R ligand, JNJ7777120, on ionizing radiation-induced injury and genotoxic damage in small intestine, salivary glands and hematopoietic tissue. For that purpose, rats were divided into 4 groups. JNJ7777120 and JNJ7777120-irradiated groups received a daily subcutaneous JNJ7777120 injection (10 mg/kg) starting 24 h be...

  17. 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.)

  18. The potential benefits of nicaraven to protect against radiation-induced injury in hematopoietic stem/progenitor cells with relative low dose exposures

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    Ali, Haytham [Department of Stem Cell Biology, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Department of Medical Physiology and Cell Biology, Qena Faculty of Medicine, South Valley University (Egypt); Galal, Omima [Department of Medical Physiology and Cell Biology, Qena Faculty of Medicine, South Valley University (Egypt); Urata, Yoshishige; Goto, Shinji; Guo, Chang-Ying; Luo, Lan [Department of Stem Cell Biology, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Abdelrahim, Eman [Department of Medical Histology, Qena Faculty of Medicine, South Valley University (Egypt); Ono, Yusuke [Department of Stem Cell Biology, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Mostafa, Emtethal [Department of Medical Physiology and Cell Biology, Qena Faculty of Medicine, South Valley University (Egypt); Li, Tao-Sheng, E-mail: litaoshe@nagasaki-u.ac.jp [Department of Stem Cell Biology, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan)

    2014-09-26

    Highlights: • Nicaraven mitigated the radiation-induced reduction of c-kit{sup +} stem cells. • Nicaraven enhanced the function of hematopoietic stem/progenitor cells. • Complex mechanisms involved in the protection of nicaraven to radiation injury. - Abstract: Nicaraven, a hydroxyl radical-specific scavenger has been demonstrated to attenuate radiation injury in hematopoietic stem cells with 5 Gy γ-ray exposures. We explored the effect and related mechanisms of nicaraven for protecting radiation injury induced by sequential exposures to a relatively lower dose γ-ray. C57BL/6 mice were given nicaraven or placebo within 30 min before exposure to 50 mGy γ-ray daily for 30 days in sequences (cumulative dose of 1.5 Gy). Mice were victimized 24 h after the last radiation exposure, and the number, function and oxidative stress of hematopoietic stem cells were quantitatively estimated. We also compared the gene expression in these purified stem cells from mice received nicaraven and placebo treatment. Nicaraven increased the number of c-kit{sup +} stem/progenitor cells in bone marrow and peripheral blood, with a recovery rate around 60–90% of age-matched non-irradiated healthy mice. The potency of colony forming from hematopoietic stem/progenitor cells as indicator of function was completely protected with nicaraven treatment. Furthermore, nicaraven treatment changed the expression of many genes associated to DNA repair, inflammatory response, and immunomodulation in c-kit{sup +} stem/progenitor cells. Nicaraven effectively protected against damages of hematopoietic stem/progenitor cells induced by sequential exposures to a relatively low dose radiation, via complex mechanisms.

  19. The potential benefits of nicaraven to protect against radiation-induced injury in hematopoietic stem/progenitor cells with relative low dose exposures

    International Nuclear Information System (INIS)

    Ali, Haytham; Galal, Omima; Urata, Yoshishige; Goto, Shinji; Guo, Chang-Ying; Luo, Lan; Abdelrahim, Eman; Ono, Yusuke; Mostafa, Emtethal; Li, Tao-Sheng

    2014-01-01

    Highlights: • Nicaraven mitigated the radiation-induced reduction of c-kit + stem cells. • Nicaraven enhanced the function of hematopoietic stem/progenitor cells. • Complex mechanisms involved in the protection of nicaraven to radiation injury. - Abstract: Nicaraven, a hydroxyl radical-specific scavenger has been demonstrated to attenuate radiation injury in hematopoietic stem cells with 5 Gy γ-ray exposures. We explored the effect and related mechanisms of nicaraven for protecting radiation injury induced by sequential exposures to a relatively lower dose γ-ray. C57BL/6 mice were given nicaraven or placebo within 30 min before exposure to 50 mGy γ-ray daily for 30 days in sequences (cumulative dose of 1.5 Gy). Mice were victimized 24 h after the last radiation exposure, and the number, function and oxidative stress of hematopoietic stem cells were quantitatively estimated. We also compared the gene expression in these purified stem cells from mice received nicaraven and placebo treatment. Nicaraven increased the number of c-kit + stem/progenitor cells in bone marrow and peripheral blood, with a recovery rate around 60–90% of age-matched non-irradiated healthy mice. The potency of colony forming from hematopoietic stem/progenitor cells as indicator of function was completely protected with nicaraven treatment. Furthermore, nicaraven treatment changed the expression of many genes associated to DNA repair, inflammatory response, and immunomodulation in c-kit + stem/progenitor cells. Nicaraven effectively protected against damages of hematopoietic stem/progenitor cells induced by sequential exposures to a relatively low dose radiation, via complex mechanisms

  20. Rescuing Self: Transient Isolation and Autologous Transplantation of Bone Marrow Mitigates Radiation-Induced Hematopoietic Syndrome and Mortality in Mice.

    Science.gov (United States)

    Ghosh, Subhajit; Indracanti, Namita; Joshi, Jayadev; Indraganti, Prem Kumar

    2017-01-01

    The inflamed bone marrow niche shortly after total body irradiation (TBI) is known to contribute to loss of hematopoietic stem cells in terms of their number and function. In this study, autologous bone marrow transfer (AL-BMT) was evaluated as a strategy for mitigating hematopoietic form of the acute radiation syndrome by timing the collection phase (2 h after irradiation) and reinfusion (24 h after irradiation) using mice as a model system. Collection of bone marrow (BM) cells (0.5 × 10 6 total marrow cells) 2 h after lethal TBI rescued different subclasses of hematopoietic stem and progenitor cells (HSPCs) from the detrimental inflammatory and damaging milieu in vivo . Cryopreservation of collected graft and its reinfusion 24 h after TBI significantly rescued mice from lethal effects of irradiation (65% survival against 0% in TBI group on day 30th) and hematopoietic depression. Transient hypometabolic state (HMS) induced 2 h after TBI effectively preserved the functional status of HSPCs and improved hematopoietic recovery even when BM was collected 8 h after TBI. Homing studies suggested that AL-BMT yielded similar percentages for different subsets of HSPCs when compared to syngeneic bone marrow transfer. The results suggest that the timing of collection, and reinfusion of graft is crucial for the success of AL-BMT.

  1. The study on the preparation of rhIL-6 and its effects on recovery of mice from radiation-induced hematopoietic aplasia

    International Nuclear Information System (INIS)

    Yang Jicheng; Zhang Yun; Sheng Weihua

    1997-08-01

    The E coil highly expressing rhIL-6 constructed by our department was fermented and rhIL-6 products were extracted and purified. The specific activity of the purified rhIL-6 products reached 4.83 x 10 8 IU/mg. The rhIL-6 products were used to treat BALB/c mice injured by 60 Co irradiation for six days (2 μg/big/each). The results showed that the bleeding time, coagulation time and prothrombin time of the rhIL-6 treatment group were significantly shorter than those of the control group (P<0.01), the platelet count and WBC increased by 130% and 165% in the treatment group as compared with the control, the numbers of CFU-Mix cultured in vitro and CFU-s in spleen were significantly higher than those in the control group (P<0.01). These results suggest that rhIL-6 exerts beneficial effects on the recovery of mice from radiation-induced injuries of hematopoietic stem/progenitor cells, and thus helps recovery from radiation injury of bone marrow and hematopoietic function. (17 refs., 4 figs., 5 tabs.)

  2. New experimental approach to treatment of radiation-induced bone marrow aplasia: ex vivo expansion of hematopoietic cells; Nouvelle approche experimentale du traitement de l`aplasie medullaire radio-induite

    Energy Technology Data Exchange (ETDEWEB)

    Herodin, F.; Mathieu, J.; Drouet, M.; Grenier, N.; Grange, L.; Bourin, P.; Vetillard, J.; Thierry, D.; Mestries, J.C.

    1995-12-31

    The management of bone marrow aplasia secondary to accidental exposure to high doses of ionizing radiations requires new therapeutic protocols in addition to cytokine therapy. The in vitro incubation of hematopoietic stem and progenitor cells from irradiated nonhuman primates with negative and positive regulators of hematopoiesis may lead to helpful products of transfusion. (author).

  3. The potential benefits of nicaraven to protect against radiation-induced injury in hematopoietic stem/progenitor cells with relative low dose exposures.

    Science.gov (United States)

    Ali, Haytham; Galal, Omima; Urata, Yoshishige; Goto, Shinji; Guo, Chang-Ying; Luo, Lan; Abdelrahim, Eman; Ono, Yusuke; Mostafa, Emtethal; Li, Tao-Sheng

    2014-09-26

    Nicaraven, a hydroxyl radical-specific scavenger has been demonstrated to attenuate radiation injury in hematopoietic stem cells with 5Gy γ-ray exposures. We explored the effect and related mechanisms of nicaraven for protecting radiation injury induced by sequential exposures to a relatively lower dose γ-ray. C57BL/6 mice were given nicaraven or placebo within 30min before exposure to 50mGy γ-ray daily for 30days in sequences (cumulative dose of 1.5Gy). Mice were victimized 24h after the last radiation exposure, and the number, function and oxidative stress of hematopoietic stem cells were quantitatively estimated. We also compared the gene expression in these purified stem cells from mice received nicaraven and placebo treatment. Nicaraven increased the number of c-kit(+) stem/progenitor cells in bone marrow and peripheral blood, with a recovery rate around 60-90% of age-matched non-irradiated healthy mice. The potency of colony forming from hematopoietic stem/progenitor cells as indicator of function was completely protected with nicaraven treatment. Furthermore, nicaraven treatment changed the expression of many genes associated to DNA repair, inflammatory response, and immunomodulation in c-kit(+) stem/progenitor cells. Nicaraven effectively protected against damages of hematopoietic stem/progenitor cells induced by sequential exposures to a relatively low dose radiation, via complex mechanisms. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. 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.

  5. Increased radiosensitivity and radiation-induced apoptosis in SRC-3 knockout mice

    International Nuclear Information System (INIS)

    Jin Jie; Wang Yu; Xu Yang; Chen Shilei; Wang Junping; Ran Xinze; Su Yongping; Wang Jin

    2014-01-01

    Steroid receptor coactivator-3 (SRC-3), a multifunctional transcriptional coactivator, plays an important role in regulation of cell apoptosis in chemoresistant cancer cells. However, its role in radiation-induced apoptosis in hematopoietic cells is still unclear. In this study, we used SRC-3 knockout (SRC-3 -/- ) mice to assess the role of SRC-3 in radiation-induced hematopoietic injury in vivo. After a range of doses of irradiation, SRC-3 -/- mice exhibited lower counts of peripheral blood cells and bone marrow (BM) mononuclear cells and excessive BM depression, which resulted in a significantly higher mortality compared with wildtype mice. Moreover, BM mononuclear cells obtained from SRC-3 -/- mice showed a remarkable increase in radiation-induced apoptosis. Collectively, our data demonstrate that SRC-3 plays a role in radiation-induced apoptosis of BM hematopoietic cells. Regulation of SRC-3 might influence the radiosensitivity of hematopoietic cells, which highlights a potential therapeutic target for radiation-induced hematopoietic injury. (author)

  6. Combined Administration of Recombinant Human Megakaryocyte Growth and Development Factor and Granulocyte Colony-Stimulating Factor Enhances Multilineage Hematopoietic Reconstitution in Nonhuman Primates after Radiation-Induced Marrow Aplasia

    National Research Council Canada - National Science Library

    Farese, Ann M; Hunt, Pamela; Grab, Lisa B; MacVittie, Thomas J

    1996-01-01

    ... the combined administration of PEG-rMGDF and r-methionyl human granulocyte colonystimulating factor "r-metHuG-CSF" on hematopoietic reconstitution after 700 cGy 60Co gamma, total body irradiation in nonhuman primates...

  7. 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.

  8. 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

  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 Genomic Instability

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, William F.

    2011-03-01

    Radiation induced genomic instability can be observed in the progeny of irradiated cells multiple generations after irradiation of parental cells. The phenotype is well established both in vivo (Morgan 2003) and in vitro (Morgan 2003), and may be critical in radiation carcinogenesis (Little 2000, Huang et al. 2003). Instability can be induced by both the deposition of energy in irradiated cells as well as by signals transmitted by irradiated (targeted) cells to non-irradiated (non-targeted) cells (Kadhim et al. 1992, Lorimore et al. 1998). Thus both targeted and non-targeted cells can pass on the legacy of radiation to their progeny. However the radiation induced events and cellular processes that respond to both targeted and non-targeted radiation effects that lead to the unstable phenotype remain elusive. The cell system we have used to study radiation induced genomic instability utilizes human hamster GM10115 cells. These cells have a single copy of human chromosome 4 in a background of hamster chromosomes. Instability is evaluated in the clonal progeny of irradiated cells and a clone is considered unstable if it contains three or more metaphase sub-populations involving unique rearrangements of the human chromosome (Marder and Morgan 1993). Many of these unstable clones have been maintained in culture for many years and have been extensively characterized. As initially described by Clutton et al., (Clutton et al. 1996) many of our unstable clones exhibit persistently elevated levels of reactive oxygen species (Limoli et al. 2003), which appear to be due dysfunctional mitochondria (Kim et al. 2006, Kim et al. 2006). Interestingly, but perhaps not surprisingly, our unstable clones do not demonstrate a “mutator phenotype” (Limoli et al. 1997), but they do continue to rearrange their genomes for many years. The limiting factor with this system is the target – the human chromosome. While some clones demonstrate amplification of this chromosome and thus lend

  11. 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)

  12. 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

  13. Accidental Hypothermia,

    Science.gov (United States)

    1988-03-03

    eczema, and exfoliative dermat i t i s. Hypothermia with hypernatremic dehydration is seen in congenital larellar ichthyosis . 1 69 r* Burns, and...hypothermia in congenital lamellar ichthyosis . Ped Derm 1985; 3: 65-68. 170. Georgitis WJ, Hofeldt FD: Myxedema coma and cardiac arrest. JAMA 1982; 247: 980...implications of experimental studies. Alaska Med 1973; 15: 48-52. 184. Grice KA, Bettley FR: Skin water loss and accidental hypothermia in psoriasis, ichthyosis

  14. 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)

  15. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    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/{mu}m) 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.)

  16. 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.)

  17. Accidental Innovation

    DEFF Research Database (Denmark)

    Austin, Robert D.; Devin, Lee; Sullivan, Erin E.

    2012-01-01

    Historical accounts of human achievement suggest that accidents can play an important role in innovation. In this paper, we seek to contribute to an understanding of how digital systems might support valuable unpredictability in innovation processes by examining how innovators who obtain value from...... they incorporate accidents into their deliberate processes and arranged surroundings. By comparing makers working in varied conditions, we identify specific factors (e.g., technologies, characteristics of technologies) that appear to support accidental innovation. We show that makers in certain specified...... conditions not only remain open to accident but also intentionally design their processes and surroundings to invite and exploit valuable accidents. Based on these findings, we offer advice for the design of digital systems to support innovation processes that can access valuable unpredictability....

  18. Radiation-induced cardiovascular effects

    Science.gov (United States)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  19. Radiation-induced heterophase polymerizations

    International Nuclear Information System (INIS)

    Carenza, M.; Palma, G.

    1985-01-01

    Investigations were carried out on the morphology of particles produced in the early stages of radiation-induced heterophase polymerization of acrylonitrile in quiescent conditions over a wide temperature range both in bulk and with addition of a solvent or a comonomer. The data were compared with the corresponding data obtained in the polymerization of vinyl chloride, producing an amorphous polymer, taking into account also the kinetic behaviours of the two polymerization systems. The particle morphologies in the two systems were quite similar at low polymerization temperatures but there were considerable differences when higher temperatures were involved. This change was interpreted on the basis of differences in compatability between the liquid phase and the polymer particle phase for the two systems. In order to account for the two different kinetic behaviours, a two-phase polymerization model was formulated and also a polymerization model in which the surface of the polymer particles was the locus of polymerization. (author)

  20. Experimental radiation-induced leukemia

    International Nuclear Information System (INIS)

    Upton, A.C.

    1977-01-01

    Of the various neoplasms induced by ionizing radiation in human and animal populations, leukemias and lymphomas were among the first to receive systematic study and have remained under intensive investigation up to the present time. The reticular tissue neoplasm that has been the most thoroughly studied is a lymphoma of the thymus which characteristically predominates in whole- bodyirradiated mice. Thanks to intensive research on this tumor, much is now known about its pathogenesis. The purpose of this report is to review the knowledge of pathogenesis of other types of radiation-induced leukemias and lymphomas, in an effort to assess the extent to which the comparative data for all such diseases can be integrated into a single unifying framework

  1. Particle radiation-induced genetic damage in vivo

    International Nuclear Information System (INIS)

    Chang, P.Y.; Bakke, J.; Lin, S.

    2003-01-01

    Full text: Assessment of radiation-induced alterations in the genomic is important to determine both short and long-term effects after exposure. Transgenic mouse mutation model systems, based on the insertion of specific target genes into the genome of every cell of the animals, provide a rapid and efficient means to obtain statistically reliable results on the frequencies of mutations in all tissues without requiring prior drug selection and clonal expansion of the target cells. We are using the plasmid-based lacZ transgenic mouse model system to measure the dose- and temporal-dependent particle-radiation induced responses. We measured cytogenetic damage to the hematopoietic system as well as mutations in the transgene in both the brain and spleen tissues after an acute dose of 250 MeV/amu protons or 1 GeV/amu iron ions. The level of peripheral blood micronucleated reticulocytes (MN-RET) increased dramatically within 48 h after whole body exposure for both proton or iron irradiated animals and returned to control levels within 1 week after treatment suggesting that these severely damaged transient cell populations are rapidly eliminated from the body. Mutation frequencies (MF) of the lacZ transgene increased as a function of proton dose in the spleen and brain tissues at 1, 8 and 16 wks post irradiation. We demonstrated that the MF of the lacZ target transgene was responsive to low doses of protons with significant increases in the MF (p 0.5 Gy iron ions. The overall magnitude of induction of lacZ MF in the brain is lower than that of the spleen, suggesting that radiation-induced genetic effects are tissue-specific, and tissue physiology plays a role in determining the late effects after particle radiation. This work was supported by NASA/NSBRI NCC 9-58-163

  2. Novel Radiomitigator for Radiation-Induced Bone Loss

    Science.gov (United States)

    Schreurs, A-S; Shirazi-fard, Y.; Terada, M.; Alwood, J. S.; Steczina, S.; Medina, C.; Tahimic, C. G. T.; Globus, R. K.

    2016-01-01

    Radiation-induced bone loss can occur with radiotherapy patients, accidental radiation exposure and during long-term spaceflight. Bone loss due to radiation is due to an early increase in oxidative stress, inflammation and bone resorption, resulting in an imbalance in bone remodeling. Furthermore, exposure to high-Linear Energy Transfer (LET) radiation will impair the bone forming progenitors and reduce bone formation. Radiation can be classified as high-LET or low-LET based on the amount of energy released. Dried Plum (DP) diet prevents bone loss in mice exposed to total body irradiation with both low-LET and high-LET radiation. DP prevents the early radiation-induced bone resorption, but furthermore, we show that DP protects the bone forming osteoblast progenitors from high-LET radiation. These results provide insight that DP re-balances the bone remodeling by preventing resorption and protecting the bone formation capacity. This data is important considering that most of the current osteoporosis treatments only block the bone resorption but do not protect bone formation. In addition, DP seems to act on both the oxidative stress and inflammation pathways. Finally, we have preliminary data showing the potential of DP to be radio-protective at a systemic effect and could possible protect other tissues at risk of total body-irradiation such as skin, brain and heart.

  3. Radiation-induced parotid cancer

    International Nuclear Information System (INIS)

    Walker, M.J.; Chaudhuri, P.K.; Wood, D.C.; Das Gupta, T.K.

    1981-01-01

    A retrospective analysis of 72 cases of primary malignant tumors of the parotid gland treated at the University of Illinois Hospital, Chicago, from 1950 through 1978 revealed that six of these had developed from two to 24 years after irradiation of the head or neck for various benign and malignant neoplastic conditions. At the time of irradiation, ages ranged from 7 to 73 years; the sex distribution was equal. From our findings and those in 26 cases reported by various other authors, the following criteria are proposed for the designation of a parotid tumor as being radiation induced: (1) well-documented radiation exposure; (2) part of irradiation must incorporate the gland in which the cancer subseqently arises; (3) exposure to a minimum of 300 rads; and (4) minimum latent period of two years. In view of the widespread use in the past of heat and neck irradiation of benign neoplastic disease, the surgeon should be aware of this possible link with parotid gland tumor

  4. 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

  5. Radiation-Induced Liver Toxicity.

    Science.gov (United States)

    Munoz-Schuffenegger, Pablo; Ng, Sylvia; Dawson, Laura A

    2017-10-01

    The advent of highly conformal radiation therapy (RT) has defined a new role for RT in the treatment of both primary and metastatic liver cancer. Despite major advances in how RT is delivered, radiation-induced liver disease (RILD) remains a concern. Classic RILD, characterized by anicteric ascites and hepatomegaly, is unlikely to occur if treating to doses of ≤30Gy in 2Gy per fraction in patients with baseline Child-Pugh A liver function. On the other hand, nonclassic RILD is a spectrum of liver toxicity, including a general decline in liver function and elevation of liver enzymes. It is less well defined and less predictable, especially in patients with underlying liver disease. Scoring and quantifying RILD remains a challenge. The Child-Pugh score has been the most consistently used parameter. Other scoring systems such as the albumin-bilirubin score provide further discrimination in patients with hepatocellular carcinoma, although their value in patients treated with RT remains to be established. Many serum and imaging biomarkers of liver function are currently being investigated, and they will provide further useful information in the future for local and global liver function assessment, for planning optimization, and for treatment adaptation. To date, no pharmacological therapies have provided consistent results in mitigating RILD once it has manifested clinically. Numerous promising treatment strategies including TGFβ inhibition, Hedgehog inhibition, CXCR4 inhibition, hepatocyte transplantation, and bone marrow-derived stromal cell therapy, have potential to be helpful in the treatment of RILD in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Radiation-induced carcinoma of the penis

    International Nuclear Information System (INIS)

    Wells, A.D.; Pryor, J.P.

    1986-01-01

    Two patients with carcinoma of the penis were treated with interstitial radiation. They were cured of their disease for 17 and 21 years respectively and then developed radiation-induced tumours. (author)

  7. Radiation Induced Bystander Effect in vivo

    OpenAIRE

    Chai, Yunfei; Hei K. Tom

    2009-01-01

    Radiation-induced bystander effect is defined as the induction of biological effects in cells that are not directly traversed by radiation, but merely in the presence of cells that are. Although radiation induced bystander effects have been well defined in a variety of in vitro models using a range of endpoints including clonogenic survival, mutations, neoplastic transformation, apoptosis, micronucleus, chromosomal aberrations and DNA double strand breaks, the mechanism(s) as well as the pres...

  8. Radiation-Induced Vaccination to Breast Cancer

    Science.gov (United States)

    2015-10-01

    Award Number: W81XWH-11-1-0531 TITLE: Radiation-Induced Vaccination to Breast Cancer PRINCIPAL INVESTIGATOR: William H. McBride CONTRACTING...FORM TO THE ABOVE ADDRESS. 1. REPORT DATE 2. REPORT TYPE Annual 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Radiation-Induced Vaccination to...determine abscopal responses that are hypothesized to be due to RT- induced vaccination . RT was started 10 days after the first and 3rd dose of

  9. Radiation Induced Vaccination to Breast Cancer

    Science.gov (United States)

    2016-12-01

    Award Number: W81XWH-11-1-0531 TITLE: Radiation-Induced Vaccination to Breast Cancer PRINCIPAL INVESTIGATOR: William H. McBride CONTRACTING...TITLE AND SUBTITLE Radiation-Induced Vaccination to Breast Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11-1-0531 5c. PROGRAM ELEMENT NUMBER 6...therapy to generate an in situ tumor vaccine and abscopal effects at distant tumor sites (13), giving some rationale for this attempt to examine this

  10. Protective effect of Kit signaling for melanocyte stem cells against radiation-induced genotoxic stress.

    Science.gov (United States)

    Aoki, Hitomi; Hara, Akira; Motohashi, Tsutomu; Kunisada, Takahiro

    2011-09-01

    Radiation-induced hair graying is caused by irreversible defects in the self-renewal and/or development of follicular melanocyte stem cells in the hair follicles. Kit signaling is an essential growth and differentiation signaling pathway for various cell lineages including melanocytes, and its radioprotective effects have been shown in hematopoietic cells. However, it is uncertain whether Kit signaling exerts a radioprotective effect for melanocytes. In this study, we found that various loss-of-function mutations of Kit facilitate radiation-induced hair graying. In contrast, transgenic mice expressing the ligand for Kit (Kitl) in the epidermis have significantly reduced levels of radiation-induced hair graying. The X-ray doses used did not show a systemic lethal effect, indicating that the in vivo radiosensitivity of Kit mutants is mainly caused by the damaged melanocyte stem cell population. X-ray-damaged melanocyte stem cells seemed to take the fate of ectopically pigmented melanocytes in the bulge regions of hair follicles in vivo. Endothelin 3, another growth and differentiation factor for melanocytes, showed a lesser radioprotective effect compared with Kitl. These results indicate the prevention of radiation-induced hair graying by Kit signaling.

  11. 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 60 Co 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)

  12. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Directory of Open Access Journals (Sweden)

    Dörr Harald

    2011-11-01

    Full Text Available Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

  13. 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.

  14. The effects of radioprotective agents on the radiation-induced DNA single strand breaks

    International Nuclear Information System (INIS)

    Rhiu, Sung Ryul; Ko, Kyung Hwan; Jung, In Yong; Cho, Chul Ku; Kim, Tae Hwan; Park, Woo Wiun; Kim, Sung Ho; Ji, Young Hoon; Kim, Kyung Jung; Bang, Hio Chang; Jung, Young Suk; Choi, Moon Sik

    1992-04-01

    With the increased use of atomic energy in science, industry, medicine and public power production, the probability of nuclear accidents certainly appears to be on the increase. Therefore, early medical diagnosis and first-aid are needed urgently to establish an efficient treatment. We carried out the studies of radiation protector such as DDC, MEA, WR-2721 and variety of decontaminator with a view to establishing the protective measure and diagnostic standards for safety of worker and neighbors living around the radiation area in case of occurring the accidental contamination. In this experiment, we examined radiation-induced DNA single strand breaks as one of the study on molecular biology of the response of cells to radiation because an understanding of the radiation-induced damage in molecular level would add to our knowledge of radiation protection and treatment. (Author)

  15. 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

  16. 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

  17. Radiation-induced leukemias in ankylosing spondylitis

    International Nuclear Information System (INIS)

    Toolis, F.; Potter, B.; Allan, N.C.; Langlands, A.O.

    1981-01-01

    Three cases of leukemia occurred in patients with ankylosing spondylitis treated by radiotherapy. In each case, the leukemic process exhibited bizarre features suggesting that radiation is likely to induce atypical forms of leukemia possessing unusual attributes not shared by spontaneously developing leukemia. The likely distinctive aspects of radiation-induced leukemia are discussed

  18. 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

  19. 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

  20. Accidental Bowel Leakage

    Science.gov (United States)

    ... nerve stimulation, injections, and surgery. What types of lifestyle changes can help treat accidental bowel leakage? Having ... Journal Clinical Updates Practice Management Coding Health Info Technology Professional Liability Managing Your Practice Patient Safety & Quality ...

  1. 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

  2. Radiation induced peroxidative damage: mechanism and significance

    International Nuclear Information System (INIS)

    Agrawal, Anjali; Kale, R.K.

    2001-01-01

    An interest has been generated in free radicals after the discovery of superoxide dismutase. These free radicals cause a number of diseases and are involved in the detrimental effect of ionizing radiation. Efforts have been made to understand their role in damage and death of the cell using lipid peroxidation process. Lipid peroxidation is an important effect of radiation on membranes, which apart from DNA, are critical targets of radiation action. This paper addresses the basic mechanism of radiation induced lipid peroxidation. Various factors, which determine the mode and magnitude of lipid peroxidation, are also discussed. Lipid peroxidation is shown to have importance in understanding the modifications of radiation effects. Efforts are made to show similarities between radiolytic and non-radiolytic lipid peroxidation. Recent findings related to the close link between radiation-induced lipid peroxidation and apoptosis are likely to open new avenues for future research and to develop new approaches for radio modification of biological effects. (author)

  3. 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)

  4. 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

  5. Radiation induced transformation of CO in cyclohexane

    International Nuclear Information System (INIS)

    Lugovoi, Y.M.; Park, H.-R.; Getoff, N.

    1989-01-01

    The radiation induced incorporation of CO in cyclohexane leads to formation of: bicyclohexylketone (G i = 2.40), α,α-bicyclohexyldiketone (G i = 0.90), cyclohexanone (G i = 0.24), cyclohexanol (G i = 0.20), cyclohexanecarboxylic acid (G i 0.10), in addition to bicyclohexyl (G i = 1.30) and polymers. The G i -values are strongly dependent on the CO-concentration in the solution. Probable reaction mechanisms are presented. (author)

  6. Modifying factors of radiation induced myeloid leukemia of C3H/He mouse

    International Nuclear Information System (INIS)

    Yoshida, Kazuko; Nishimura, Mayumi; Nemoto, Kumie; Seki, Masatoshi

    1989-01-01

    The first experiment examined modifying factors, such as adrenocortical hormones, inflammatory reaction, and surgical stress, for radiation induced myeloid leukemia in C3H/He mice. The incidence of myeloid leukemia was not affected by a solitary subcutaneous injection of one mg of prednisolone acetate (predonine), but increased significantly by whole body irradiation, immediately followed by predonine. Augumentated effects of predonine was found in the 0.47 Gy, 1.42 Gy, and 2.84 Gy irradiated groups, but not found in the 4.73 Gy irradiated group. These results suggest that predonine itself did not have any effect on initiation of leukemogenesis, but promoted the incidence of radiation-induced myeloid leukemia. In the next experiment determining whether the incidence of myeloid leukemia was increased with stimulation of hematopoietic tissues, mice were inserted a piece of cellulose acetate membrane (CAM) into the peritoneal cavity. In the non-irradiated group of mice, CAM insertion did not affect the incidence of myeloid leukemia at all. The incidence of leukemia increased significantly by CAM insertion combined with irradiation of 2.84 Gy. Mice suffered from both surgical stress and inflammatory reaction after CAM insertion. Therefore, surgical stress was considered responsible for the development of radiation-induced leukemia. (Namekawa, K)

  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. 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.)

  9. Medical management of accidentally exposed individuals

    International Nuclear Information System (INIS)

    Nenot, J.C.

    1998-01-01

    Bone marrow aplasia is one of the main syndromes following a high dose accidental radiation exposure. Whilst transfusion and bone marrow transplantation have been used with some success starting with the first treatments of accident victims, other therapeutic strategies are needed. With the development of experimental and clinical haematology, promising new approaches to the treatment of aplasia have appeared. New trends for the treatment of haemopoietic injury based on bone marrow transplantation rely on new sources of compatible donor cells, such as cord blood, on the selection of immature haemopoietic cells and on new transplant regimens. Haemopoietic growth factors stimulate the proliferation and/or differentiation of haemopoietic progenitors and, possibly, stem cells. Furthermore, they act on the functions of mature cells. Currently, they have specific uses in haematology related to their role in the regulation of growth and in the differentiation of haemopoietic progenitor cells. Growth factors have already been used for the treatment of accidental radiation induced aplasia and lessons have been learned from their medical management and followup. (author)

  10. 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...

  11. Radiation induced early onset of neuro-cognitive changes

    International Nuclear Information System (INIS)

    Kumar, Mayank; Haridas, Seenu; Gupta, Mamta; Trivedi, Richa; Khushu, Subhash; Manda, Kailash

    2012-01-01

    Exposure to ionizing radiations has been shown to cause many detrimental effects. Primarily, the effects observed are broadly classified into hematopoietic syndrome at lower doses, gastrointestinal syndrome and central nervous system dysfunctions at high doses. However, recent studies reported that even at lower doses, there is an effect seen on the nervous system which can be observed as a decline in cognitive abilities. This has been reported in patients undergoing radiotherapy. The cognitive decline, especially in young patients affects development and has been shown to persist for years after the therapy. Thus, the aim of this study was to study and consolidate the early effects of radiation exposure which result in behavioural alterations and cognitive decline. Since, radiation-induced early changes in behavioural functions are poorly understood, therefore, the present investigation aimed to conceptualize and design behavioural test batteries in order to systematically study the immediate alterations in behavioural function following irradiation with a-rays. The behavioural alterations were correlated to changes in the different area of brain like hippocampus, thalamus, hypothalamus and corpus callosum using Diffusion Tensor Imaging (DTI) studies. Present study reported profound changes in behaviour, as well as alterations in the morphology of the brain tissue as perceived by DTI, 48 hours after exposure to ionizing radiations. These changes need to be correlated and clarified further to understand the mechanisms behind the cognitive dysfunctions occurring immediately after radiation exposure as well as to find out a therapeutic window to counteract or reduce the effect of long term cognitive changes following irradiation. (author)

  12. Radiation-induced diffusion at ionic etching

    International Nuclear Information System (INIS)

    Protsenko, A.N.; Chajkovskij, Eh.F.

    1986-01-01

    Effect of radiation-induced diffusion (RID) on profiles of cesium implanted into tantalum, tungsten and molybdenum with 100 keV energy was studied. Layer-by-layer analysis was performed by means of 4 keV argon ions and 100 μA/cm 2 beam density. For the case under investigation an integral equation, which solution permitted to determine impurity true distribution, has been derived. It is shown that RID taking place on ionic etching results in broadening and shifting cesium profiles peaks into the deep of a specimen and so perverts results of the layer-by-layer analysis

  13. 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

  14. A report on radiation-induced gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Salvati, M.; Artico, M.; Caruso, R.; Rocchi, G.; Orlando, E.R.; Nucci, F. (Univ. of Rome La Sapienza (Italy))

    1991-01-15

    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.

  15. 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

  16. 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.)

  17. 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

  18. Micronuclei: sensitivity for the detection of radiation induced damage

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Nasazzi, N.B.; Taja, M.R.

    1998-01-01

    The in vitro cytokinesis-block (CB) micronucleus (MN) assay for human peripheral blood has been used extensively for the assessment of chromosomal damage induced by ionizing radiation and chemicals and considered a suitable biological dosimeter for estimating in vivo whole body exposures, particularly in the case of large scale radiation accidents. One of the major drawbacks of the MN assay is its reduced sensitivity for the detection of damage induced by low doses of low LET radiation, due to the high variability among the spontaneous MN frequencies. It is suggested that age, smoking habit and sex are the main confounding factors that contribute to the observed variability. Previous work in our laboratory, shows a significant positive correlation of the spontaneous and radiation induced MN frequencies with age and smoking habit, the latter being the strongest confounder. These findings led to in vitro studies of the dose-response relationships for smoking and non smoking donors evaluated separately, using 60 Co γ rays. The objectives of the present work are: 1-To increase the amount of data of the dose-response relationships, using γ rays from a 60 Co source, for smoking and non smoking donors, in order to find, if applicable, a correction factor for the calibration curve that takes into account the smoking habit of the individual in the case of accidental overexposure dose assessment, particularly in the low dose range. 2-To establish general conclusions on the current state of the technique. The sample for smoking and non smoking calibration curves was enlarged in the range of 0Gy to 2Gy. The fitting of both curves, performed up to the 2Gy dose, resulted in a linear quadratic model. MN distribution among bi nucleated cells was found to be over dispersed with respect to Poisson distribution, the average ratio of variance to mean being 1.13 for non smokers and 1.17 for smokers. Each fitted calibration curve, for smoking and non smoking donors, fell within the 95

  19. Modeling the Accidental Deaths

    Directory of Open Access Journals (Sweden)

    Mariyam Hafeez

    2008-01-01

    Full Text Available The model for accidental deaths in the city of Lahore has been developed by using a class of Generalized Linear Models. Various link functions have been used in developing the model. The diagnostic checks have been carried out to see the validity of the fitted model.

  20. 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

  1. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kandasamy, S.B.; Hunt, W.A.; Harris, A.H. (Armed Forces Radiobiology Research Institute, Bethesda, MD (USA))

    1991-05-01

    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.

  3. 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

  4. 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

  5. Transesophageal Echocardiography and Radiation-induced Damages.

    Science.gov (United States)

    Cottini, Marzia; Polizzi, Vincenzo; Pino, Paolo Giuseppe; Buffa, Vitaliano; Musumeci, Francesco

    2016-01-01

    The long-term sequelae of mantle therapy include, especially lung and cardiac disease but also involve the vessels and the organs in the neck and thorax (such as thyroid, aorta, and esophagus). We presented the case of 66-year-old female admitted for congestive heart failure in radiation-induced heart disease. The patient had undergone to massive radiotherapy 42 years ago for Hodgkin's disease (type 1A). Transesophageal echocardiography was performed unsuccessfully with difficulty because of the rigidity and impedance of esophageal walls. Our case is an extraordinary report of radiotherapy's latency effect as a result of dramatic changes in the structure of mediastinum, in particular in the esophagus, causing unavailability of a transesophageal echocardiogram.

  6. 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)

  7. 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

  8. Calorie restriction reduces the incidence of radiation-induced myeloid leukemia and spontaneous tumor

    International Nuclear Information System (INIS)

    Yoshida, Kazuko

    1999-01-01

    The host-defense mechanisms against cancers are known to be modulated by changing the environmental factor(s). The spontaneous incidence of myeloid leukemia is about 1% in C3H/He mice, and the incidence increases up to 23.3% when a single dose of radiation, 3 Gy X-ray, is exposed to a whole-body. Since calorie restriction was known to reduce the incidence of spontaneous tumors, a question as to whether such radiation induced-increase of myeloid leukemia would be also decreased by calorie restriction, was aimed to answer to elucidate possible mechanism of radiation-induced myeloid leukemia. By the calorie restriction, the incidence of myeloid leukemia was significantly decreased; it was reduced to 7.9% and 10.7% when restriction was started before (6 weeks old) and after (10 weeks old) irradiation, respectively. In addition, the latent period of the myeloid leukemia in the groups for calorie restriction was significantly extended at a greater extent as compared with the control diet groups. Number of hematopoietic stem cells, the possible target cells for radiation-induced leukemias, in the groups for the calorie restriction demonstrated a significant decrease, especially in the spleen, as compared with that in the control, when the evaluation was made at the time of radiation exposure. Then, we examined whether the decreased number of target cells at the time of exposure is caused by the reduction of radiation-induced myeloid leukemia with caloric restriction. The third restricted groups were fed 65 kcal diet (restricted diet) for the first 4 weeks i.e. from 6 weeks to 10 weeks old, then, the mice were fed with control diet after radiation. The incidence of myeloid leukemia in this group was slightly decreased but did not show statistically significance. Therefore, the caloric restriction seems to be more effective in the promotion stage than the initiation stage on radiation-induced leukemogenesis. It is well known that C3H/He mice develop hepatoma spontaneously

  9. Calorie restriction reduces the incidence of radiation-induced myeloid leukemia and spontaneous tumor

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Kazuko [National Inst. of Radiological Sciences, Chiba (Japan)

    1999-06-01

    The host-defense mechanisms against cancers are known to be modulated by changing the environmental factor(s). The spontaneous incidence of myeloid leukemia is about 1% in C3H/He mice, and the incidence increases up to 23.3% when a single dose of radiation, 3 Gy X-ray, is exposed to a whole-body. Since calorie restriction was known to reduce the incidence of spontaneous tumors, a question as to whether such radiation induced-increase of myeloid leukemia would be also decreased by calorie restriction, was aimed to answer to elucidate possible mechanism of radiation-induced myeloid leukemia. By the calorie restriction, the incidence of myeloid leukemia was significantly decreased; it was reduced to 7.9% and 10.7% when restriction was started before (6 weeks old) and after (10 weeks old) irradiation, respectively. In addition, the latent period of the myeloid leukemia in the groups for calorie restriction was significantly extended at a greater extent as compared with the control diet groups. Number of hematopoietic stem cells, the possible target cells for radiation-induced leukemias, in the groups for the calorie restriction demonstrated a significant decrease, especially in the spleen, as compared with that in the control, when the evaluation was made at the time of radiation exposure. Then, we examined whether the decreased number of target cells at the time of exposure is caused by the reduction of radiation-induced myeloid leukemia with caloric restriction. The third restricted groups were fed 65 kcal diet (restricted diet) for the first 4 weeks i.e. from 6 weeks to 10 weeks old, then, the mice were fed with control diet after radiation. The incidence of myeloid leukemia in this group was slightly decreased but did not show statistically significance. Therefore, the caloric restriction seems to be more effective in the promotion stage than the initiation stage on radiation-induced leukemogenesis. It is well known that C3H/He mice develop hepatoma spontaneously

  10. Studies on hematopoietic cell apoptosis and the relative gene expression in irradiated mouse bone marrow

    International Nuclear Information System (INIS)

    Peng Ruiyun; Wang Dewen; Xiong Chengqi; Gao Yabing; Yang Hong; Cui Yufang; Wang Baozhen

    2001-01-01

    Objective: To study apoptosis and expressions bcl-2 and p53 in irradiated mouse bone marrow. Methods: LACA mice were irradiated with 60 Co γ-rays. By means of in situ terminal labelling, in situ hybridization and image analysis, the authors studied radiation-induced apoptosis of hematopoietic cells and the expressions of bcl-2 and p53. Results: The characteristics of apoptosis appeared in hematopoietic cells at 6 hrs after irradiation. The expression of bcl-2 was obviously decreased when apoptosis of hematopoietic cells occurred, whereas it increased in the early recovery phase; p53 protein increased during both apoptosis of hematopoietic cells and the recovery phase, and mutant type p53 DNA was positive only in the recovery phase. Conclusion: Radiation may induced apoptosis of hematopoietic cells in a dose-dependent manner; Both bcl-2 and p53 genes play an important role in apoptosis and recovery phase

  11. 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.

  12. 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

  13. 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 ...

  14. 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 ...

  15. 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

  16. [Medical prevention and treatment of radiation-induced pulmonary complications].

    Science.gov (United States)

    Vallard, A; Rancoule, C; Le Floch, H; Guy, J-B; Espenel, S; Le Péchoux, C; Deutsch, É; Magné, N; Chargari, C

    2017-08-01

    Radiation-induced lung injuries mainly include the (acute or sub-acute) radiation pneumonitis, the lung fibrosis and the bronchiolitis obliterans organizing pneumonia (BOOP). The present review aims at describing the diagnostic process, the current physiopathological knowledge, and the available (non dosimetric) preventive and curative treatments. Radiation-induced lung injury is a diagnosis of exclusion, since clinical, radiological, or biological pathognomonic evidences do not exist. Investigations should necessarily include a thoracic high resolution CT-scan and lung function tests with a diffusing capacity of the lung for carbon monoxide. No treatment ever really showed efficacy to prevent acute radiation-induced lung injury, or to treat radiation-induced lung fibrosis. The most promising drugs in order to prevent radiation-induced lung injury are amifostine, angiotensin-converting-enzyme inhibitors and pentoxifylline. Inhibitors of collagen synthesis are currently tested at a pre-clinical stage to limit the radiation-induced lung fibrosis. Regarding available treatments of radiation-induced pneumonitis, corticoids can be considered the cornerstone. However, no standardized program or guidelines concerning the initial dose and the gradual tapering have been scientifically established. Alternative treatments can be prescribed, based on clinical cases reporting on the efficacy of immunosuppressive drugs. Such data highlight the major role of the lung dosimetric protection in order to efficiently prevent radiation-induced lung injury. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  17. Enhanced hematopoietic protection from radiation by the combination of genistein and captopril.

    Science.gov (United States)

    Day, R M; Davis, T A; Barshishat-Kupper, M; McCart, E A; Tipton, A J; Landauer, M R

    2013-02-01

    The hematopoietic system is sensitive to radiation injury, and mortality can occur due to blood cell deficiency and stem cell loss. Genistein and the angiotensin converting enzyme (ACE) inhibitor captopril are two agents shown to protect the hematopoietic system from radiation injury. In this study we examined the combination of genistein with captopril for reduction of radiation-induced mortality from hematopoietic damage and the mechanisms of radiation protection. C57BL/6J mice were exposed to 8.25Gy (60)Co total body irradiation (TBI) to evaluate the effects of genistein and captopril alone and in combination on survival, blood cell recovery, hematopoietic progenitor cell recovery, DNA damage, and erythropoietin production. 8.25Gy TBI resulted in 0% survival after 30days in untreated mice. A single subcutaneous injection of genistein administered 24h before TBI resulted in 72% survival. Administration of captopril in the drinking water, from 1h through 30days postirradiation, increased survival to 55%. Genistein plus captopril increased survival to 95%. Enhanced survival was reflected in a reduction of radiation-induced anemia, improved recovery of nucleated bone marrow cells, splenocytes and circulating red blood cells. The drug combination enhanced early recovery of marrow progenitors: erythroid (CFU-E and BFU-E), and myeloid (CFU-GEMM, CFU-GM and CFU-M). Genistein alone and genistein plus captopril protected hematopoietic progenitor cells from radiation-induced micronuclei, while captopril had no effect. Captopril alone and genistein plus captopril, but not genistein alone, suppressed radiation-induced erythropoietin production. These data suggest that genistein and captopril protect the hematopoietic system from radiation injury via independent mechanisms. Published by Elsevier B.V.

  18. 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)

  19. Protective effect of flax seed oil against radiation induced hematological alterations in mammals

    International Nuclear Information System (INIS)

    Sharma, Jyoti; Singh, Ritu; Goyal, P.K.; Singh, Seema

    2014-01-01

    Human beings are exposed to ionizing and non ionizing radiation from natural as well as manmade sources. Ionizing radiations are one of the predominant exogenous factors that have deleterious consequences to human life. Exposure to ionizing radiations damages the hematopoietic, gastrointestinal or central nervous systems, depending on radiation dose. Hence, there is an urgent need to prevent such deleterious effects caused due to ionizing radiations. Chemical protection involves the use of synthetic and natural products against planned radiation exposure. Medicinal plants are rich in antioxidants and their chemical constituents may be the potential source for radioprotective agents. Linum usitatissimum plant (family: Linaceae), source of flaxseed oil (FSO), is well known for its anticarcinogenic, antidiabetic, cardioprotector, antiulcer properties owing to the presence of various phytochemicals. The present study has been focused to find out the preventive action of flaxseed oil against radiation induced hematological and biochemical lesions in mammals. For this purpose, FSO (50μL/animal/day) was orally administered to Swiss albino mice for five days, prior to 6 Gy gamma radiation exposure. The animals were sacrificed on 1 st , 3 rd , 7 th , 15 th and 30 th day after irradiation. Radiation treated control group exhibited significant reduction in erythrocytes count, hemoglobin content, hematocrit value and total WBC count in peripheral blood. In contrast, pretreatment with FSO significantly increased all these blood constituents. Further, the antioxidant parameters such as reduced glutathione, catalase, and superoxide dismutase showed a significant elevation in FSO pretreated group which were reduced in irradiated control group. Similarly, radiation induced increase lipid peroxidation in blood was significantly inhibited after FSO treatment. The present results indicate that the flaxseed oil has the ability to debilitate the radiation induced adverse alterations in

  20. Radiation-induced cancer in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Shoji; Sekizuka, Eiichi [National Saitama Hospital, Wako (Japan); Yamashita, Hisao [Keio Cancer Center, Tokyo (Japan); Takami, Akira [Yamawaki Coll., Tokyo (Japan); Kubo, Atsushi [Keio Univ., Tokyo (Japan). School of Medicine

    2001-12-01

    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 pharynxy (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

  1. 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

  2. Gamma radiation induced micronuclei and erythrocyte cellular abnormalities in the fish Catla catla

    Energy Technology Data Exchange (ETDEWEB)

    Anbumani, S. [Biodosimetry Laboratory, Radiological Safety Division, Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamilnadu 603102 (India); Mohankumar, Mary N., E-mail: marynmk@rediffmail.com [Biodosimetry Laboratory, Radiological Safety Division, Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamilnadu 603102 (India)

    2012-10-15

    Ionizing radiation induced DNA damage in fishes is a scarcely studied topic and very few studies are available in fishes exposed to ionizing radiation using the erythrocyte micronucleus assay under laboratory conditions. Since radionuclides released accidentally or during a nuclear disaster can contaminate inland water bodies, biomonitoring methods are required for assessing the impacts of high and low levels of radiation that may ultimately result in ionizing radiation exposure to both humans and non-human biota. Fresh water fish, Catla catla were subjected to protracted (0.002 Gy/min) and acute (3.2 Gy/min) gamma radiation to a total dose of 5 Gy. Peripheral blood samples were collected at different intervals (days 3, 6, 12, 18, 30, 45, 90, 135, 202) and analyzed by the erythrocyte micronucleus assay. Nuclear anomalies observed were micronuclei (MN), deformed nuclei (DN), nuclear bud (NBu), nuclear bridge (NBr), vacuolated nucleus (VN), binucleated cell (BNC), apoptotic cells (AC) while cytoplasmic abnormalities detected were vacuolated cytoplasm (VC), anisochromasia (AN), echinocytes (EC) and enucleus (EN). Both exposures caused a statistically significant increase in nuclear and cytoplasmic abnormalities that correlated with micronucleus and other nuclear anomalies. However, the extent of damage is higher after an acute exposure lasting for a longer period leading to apoptosis. Nuclear and cytoplasmic abnormalities are the resultants of gamma radiation induced genotoxicity and cytotoxicity.

  3. 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.

  4. 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)

  5. 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

  6. 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

  7. 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)

  8. 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

  9. 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

  10. Radiation induced lung injury: prediction, assessment and management.

    Science.gov (United States)

    Giridhar, Prashanth; Mallick, Supriya; Rath, Goura Kishore; Julka, Pramod Kumar

    2015-01-01

    Radiation induced lung injury has long been considered a treatment limiting factor for patients requiring thoracic radiation. This radiation induced lung injury happens early as well as late. Radiation induced lung injury can occur in two phases viz. early (radiation pneumonitis and late (>6 months) when it is called radiation induced lung fibrosis. There are multiple factors that can be patient, disease or treatment related that predict the incidence and severity of radiation pneumonitis. Radiation induced damage to the type I pneumocytes is the triggering factor to initiate such reactions. Over the years, radiation therapy has witnessed a paradigm shift in radiation planning and delivery and successfully reduced the incidence of lung injury. Radiation pneumonitis is usually a diagnosis of exclusion. Steroids, ACE inhibitors and pentoxyphylline constitute the cornerstone of therapy. Radiation induced lung fibrosis is another challenging aspect. The pathophysiology of radiation fibrosis includes continuing inflammation and microvascular changes due to pro-angiogenic and pro- fibrogenic stimuli resembling those in adult bronchiectasis. General supportive management, mobilization of airway secretions, anti-inflammatory therapy and management of acute exacerbations remains the treatment option. Radiation induced lung injury is an inevitable accompaniment of thoracic radiation.

  11. Radioprotection against radiation induced bone marrow syndrome by a semi-synthetic derivative of chlorophyll

    International Nuclear Information System (INIS)

    Suryavanshi, Shweta; Sharma, Deepak; Checker, Rahul; Santosh Kumar, S.; Sainis, Krishna B.

    2014-01-01

    A plethora of biological properties have been attributed to chlorophyllin (CHL), the water soluble derivative of the green plant pigment chlorophyll. Several studies are available describing its ability to modify genotoxic effects. It has been shown that administration CHL to human lymphopenic individuals led to the recovery and restoration of the immune system and also inhibited aflatoxin B1-DNA binding in individuals residing in high risk exposure to this liver carcinogen. The present study is aimed at establishing radioprotective efficacy of CHL against ionizing radiation induced hematopoietic syndrome. CHL offered complete protection against whole body irradiation (WBI, 7 Gy) induced mortality in mice. This observation was supported by increase in the number of macroscopic endogenous colonies enumerated on the surface of the spleens taken from CHL+WBI group as compared to WBI group. Radioprotection by CHL was found to be mediated by increasing the frequency of hematopoietic stem cells (HSCs) as evaluated by side population assay. Administration of CHL induced G1 arrest in bone marrow cells, increased number of granulocytes and neutrophils in the peripheral blood. At the molecular level, activation of ERK was observed in bone marrow cells obtained from CHL administered mice. In conclusion, CHL mediated radioprotection was attributed to increased stem cell numbers, G1 arrest in bone marrow cells, increased neutrophil numbers and ERK activation. (author)

  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. Insulin-Like Growth Factor 1 Mitigates Hematopoietic Toxicity After Lethal Total Body Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Dunhua; Deoliveira, Divino; Kang, Yubin; Choi, Seung S. [Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States); Li, Zhiguo [Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina (United States); Chao, Nelson J. [Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States); Department of Pathology, Duke University Medical Center, Durham, North Carolina (United States); Department of Immunology, Duke University Medical Center, Durham, North Carolina (United States); Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina (United States); Chen, Benny J., E-mail: chen0032@mc.duke.edu [Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina (United States); Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States)

    2013-03-15

    Purpose: To investigate whether and how insulin-like growth factor 1 (IGF-1) mitigates hematopoietic toxicity after total body irradiation. Methods and Materials: BALB/c mice were irradiated with a lethal dose of radiation (7.5 Gy) and treated with IGF-1 at a dose of 100 μg/dose intravenously once a day for 5 consecutive days starting within 1 hour after exposure. Survival and hematopoietic recovery were monitored. The mechanisms by which IGF-1 promotes hematopoietic recovery were also studied by use of an in vitro culture system. Results: IGF-1 protected 8 of 20 mice (40%) from lethal irradiation, whereas only 2 of 20 mice (10%) in the saline control group survived for more than 100 days after irradiation. A single dose of IGF-1 (500 μg) was as effective as daily dosing for 5 days. Positive effects were noted even when the initiation of treatment was delayed as long as 6 hours after irradiation. In comparison with the saline control group, treatment with IGF-1 significantly accelerated the recovery of both platelets and red blood cells in peripheral blood, total cell numbers, hematopoietic stem cells, and progenitor cells in the bone marrow when measured at day 14 after irradiation. IGF-1 protected both hematopoietic stem cells and progenitor cells from radiation-induced apoptosis and cell death. In addition, IGF-1 was able to facilitate the proliferation and differentiation of nonirradiated and irradiated hematopoietic progenitor cells. Conclusions: IGF-1 mitigates radiation-induced hematopoietic toxicity through protecting hematopoietic stem cells and progenitor cells from apoptosis and enhancing proliferation and differentiation of the surviving hematopoietic progenitor cells.

  14. 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.

  15. 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).

  16. 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

  17. 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

  18. Amelioration of Radiation-Induced Hematopoietic and Gastrointestinal Damage by Ex-RAD (trademark) in Mice

    Science.gov (United States)

    2012-06-06

    concern in therapeutic radiology [1]. Other instances of radiation exposure include accidents that can occur in nuclear power plants, potential terrorist...prevention. In: Ricks RC, Berger ME, O’Hara FM (eds). The Medical Basis for Radiation Accident Preparedness: The Clinical Care of Victims. Boca Raton...Hovdenak N., Fajardo LF, Hauer-Jensen M. Acute radiation proctitis: a sequential clinicopathologic study during pelvic radiotherapy . Int J Radiat Oncol

  19. Chronic radiation-induced leukemogenesis: alterations of hematopoietic progenitor repair functions during preclinical phases

    International Nuclear Information System (INIS)

    Seed, T.M.; Kaspar, L.V.; Grdina, D.J.; Frazier, M.E.

    1987-01-01

    Chronic exposure to low daily doses of whole-body gamma irradiation elicits a high incidence of myeloid leukemia (ML) and related myeloproliferative diseases (MPD) in beagles. Previously, the authors identified and partially characterized a four-phase sequence of evolving MPD as a consequence of chronic radiation exposure. With a focus on preclinical alterations in granulocyte/monocyte-committed stem cells, they have identified two critical events in the process: (i) an early event, involving the coupling of acquired radioresistance of the stem cell with renewed proliferative capacity; and (ii) a late event, involving acquired autocrine functions and associated change in stem cell clonality. In terms of the early event, repair-associated parameters are currently being examined on the cellular level by both split-dose and low dose-rate-type assays with survival enhancement used as the measured end point. On the molecular level, these parameters are examined by microfluorometric alkaline elution assays with DNA damage and repair used as end points

  20. 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)

  1. 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...

  2. 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

  3. Physical mechanisms of radiation induced creep in metals

    International Nuclear Information System (INIS)

    Borodin, V.A.; Ryazanov, A.I.

    1990-01-01

    Analysis of available experimental data has been conducted. It enables to correlate reliably the character of evolution of dislocation structure of irradiated materials with different stages of radiation induced creep. This provides reliable basis for the general conclusions concerning the character of some parametric dependences of deformation rate of these materials. Analysis of different modern theoretical models enables to evaluate regions of their applicability and their relative significance for radiation induced creep description. 20 refs.; 2 figs.; 1 tab

  4. 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.

  5. Radiation-induced reactions in polymer films

    Science.gov (United States)

    Biscoglio, Michael Benedict

    Since the 1950's, there has been a considerable interest in the effects of ionizing radiation on the physical properties of polymer systems. Radiation induced chemical changes that were found to be helpful in producing specialty polymers, but also potentially harmful by degrading the physical performance of the material. Therefore, solute molecules, which act as excited state quenchers, and free radical scavengers, have been incorporated into the polymers in order to regulate the crosslinking, scission and desaturation reactions. This work is focused on using spectroscopic techniques to characterize the physical properties of polymeric media and the reactions occurring within them following pulsed radiolysis. This is done primarily by using arene doped polymer films which have highly absorbing excited states and radical ions that are easily monitored by transient studies. The probes are used to characterize the polymeric microenvironment, to monitor reaction rates, and to interfere in the radical reactions. Photophysical and photochemical characterization of partially crystalline polyethylene complements data previously obtained by conventional physical techniques for polymer characterization. Probe molecules are excluded from crystalline zones and distributed in a networked structure of amorphous zones. Upon high energy radiolysis, it is found that polyolefin systems efficiently donate all radical ions and excited states to the solute molecules, even when the energy is absorbed within the polymer crystalline zones. Studies of the subsequent reactions of the solute excited states and radical ions reveal information about their long term effectiveness as protectants. It is found that highly excited states formed by the recombination of solute radical ions are energetic enough to cause dissociation of halo-arenes. Also, arenes are found to become attached to the polymer chain through a polymer-aryl radical intermediate. These intermediates have been isolated and

  6. Pro-inflammatory agents LPS and IL-6 protect monocytic cell line RAW264.7 from radiation induced cell death

    International Nuclear Information System (INIS)

    Neeraj Kumari; Rai, Yogesh; Pathak, Richa; Kalra, Namita; Sharma, Anjali; Dwarakanath, B.S.; Bhatt, Anant Narayan

    2014-01-01

    Our earlier studies have shown that increased glycolysis protects cells from radiation induced cell death. Pro-inflammatory molecules like LPS have been shown to reduce radiation induced gastro-intestinal syndrome, while IL-6 protects cardiomyocytes from ischemia induced oxidative stress. Interestingly, both pro-inflammatory molecules, LPS and IL-6 induce glycolysis in cells and mimic the high glycolytic phenotype. Therefore, we hypothesize that LPS and IL-6 can protect the hematopoietic cells from radiation induced cell death by inducing glycolysis. To validate our hypothesis, we investigated the response of RAW264.7 cells stimulated with LPS (10 ng/ml) and IL-6 (1 ng/ml), 2 hours prior to irradiation (2 Gy, gamma rays, 60 Co). Both LPS and IL-6 protected cells from radiation induced growth inhibition with > 50% increase in cell number as compared to radiation alone. Under these conditions, IL-6 showed more than 2 fold increase in glycolysis, measured by lactate production, which correlated with increased cell number. To understand the mechanisms underlying IL-6 induced radio-resistance, we examined the effects of IL-6 on anti-oxidant defence and mitochondrial status in irradiated cells. Cells treated with IL-6 showed nearly 40% reduced levels of radiation induced delayed reactive oxygen species (ROS), measured at 24 hours after exposure using DCFH2-DA. The decrease in ROS was linked to increased mitochondrial membrane potential (MMP), thereby suggesting that IL-6 induced reduction in ROS levels and high MMP protects the cell from radiation induced cell death. Our results show that both mitochondrial uncouplers and pro-inflammatory molecules (LPS and IL-6) lead to similar metabolic shift in the form of increased glycolysis leading to enhanced radio-resistance. Therefore, we propose that stimulation of glycolysis can be an useful radioprotective strategy, irrespective of the nature of stimulants. Further studies to understand mechanisms underlying IL-6 induced

  7. Allegheny County Fatal Accidental Overdoses

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Fatal accidental overdose incidents in Allegheny County, denoting age, gender, race, drugs present, zip code of incident and zip code of residence. Zip code of...

  8. 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)

  9. 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

  10. Radiation-Induced Leukemia at Doses Relevant to Radiation Therapy: Modeling Mechanisms and Estimating Risks

    Science.gov (United States)

    Shuryak, Igor; Sachs, Rainer K.; Hlatky, Lynn; Mark P. Little; Hahnfeldt, Philip; Brenner, David J.

    2006-01-01

    Because many cancer patients are diagnosed earlier and live longer than in the past, second cancers induced by radiation therapy have become a clinically significant issue. An earlier biologically based model that was designed to estimate risks of high-dose radiation induced solid cancers included initiation of stem cells to a premalignant state, inactivation of stem cells at high radiation doses, and proliferation of stem cells during cellular repopulation after inactivation. This earlier model predicted the risks of solid tumors induced by radiation therapy but overestimated the corresponding leukemia risks. Methods: To extend the model to radiation-induced leukemias, we analyzed in addition to cellular initiation, inactivation, and proliferation a repopulation mechanism specific to the hematopoietic system: long-range migration through the blood stream of hematopoietic stem cells (HSCs) from distant locations. Parameters for the model were derived from HSC biologic data in the literature and from leukemia risks among atomic bomb survivors v^ ho were subjected to much lower radiation doses. Results: Proliferating HSCs that migrate from sites distant from the high-dose region include few preleukemic HSCs, thus decreasing the high-dose leukemia risk. The extended model for leukemia provides risk estimates that are consistent with epidemiologic data for leukemia risk associated with radiation therapy over a wide dose range. For example, when applied to an earlier case-control study of 110000 women undergoing radiotherapy for uterine cancer, the model predicted an excess relative risk (ERR) of 1.9 for leukemia among women who received a large inhomogeneous fractionated external beam dose to the bone marrow (mean = 14.9 Gy), consistent with the measured ERR (2.0, 95% confidence interval [CI] = 0.2 to 6.4; from 3.6 cases expected and 11 cases observed). As a corresponding example for brachytherapy, the predicted ERR of 0.80 among women who received an inhomogeneous low

  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. 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

  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 fibrosarcoma following treatment for breast cancer

    International Nuclear Information System (INIS)

    Adam, Y.G.; Reif, R.

    1977-01-01

    A patient with radiation-induced fibrosarcoma following mastectomy and postoperative radiation for bilateral breast carcinoma is described. Only six such cases have been reported in the literature. In this patient erosion of the axillary artery produced massive hemorrhage, and emergency transthoracic ligation of the subclavian artery caused gangrene of the extremity and empyema and sepsis. Interscapulothoracic amputation not only was life-saving but offered the patient a reasonable chance for long-term survival. Only aggressive surgical management can salvage a patient with radiation-induced sarcoma

  15. Recovery From Radiation-induced Bone Marrow Damage by HSP25 Through Tie2 Signaling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hae-June [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kwon, Hee-Chung [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chung, Hee-Yong [College of Medicine, Hanyang University, Seoul (Korea, Republic of); Lee, Yoon-Jin [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yun-Sil, E-mail: yslee0425@ewha.ac.kr [College of Pharmacy and Division of Life and Pharmaceutical Sciences, Ewha Woman' s University, Seoul (Korea, Republic of)

    2012-09-01

    Purpose: Whole-body radiation therapy can cause severe injury to the hematopoietic system, and therefore it is necessary to identify a novel strategy for overcoming this injury. Methods and Materials: Mice were irradiated with 4.5 Gy after heat shock protein 25 (HSP25) gene transfer using an adenoviral vector. Then, peripheral blood cell counts, histopathological analysis, and Western blotting on bone marrow (BM) cells were performed. The interaction of HSP25 with Tie2 was investigated with mouse OP9 and human BM-derived mesenchymal stem cells to determine the mechanism of HSP25 in the hematopoietic system. Results: HSP25 transfer increased BM regeneration and reduced apoptosis following whole-body exposure to ionizing radiation (IR). The decrease in Tie2 protein expression that followed irradiation of the BM was blocked by HSP25 transfer, and Tie2-positive cells were more abundant among the BM cells of HSP25-transferred mice, even after IR exposure. Following systemic RNA interference of Tie2 before IR, HSP25-mediated radioprotective effects were partially blocked in both mice and cell line systems. Stability of Tie2 was increased by HSP25, a response mediated by the interaction of HSP25 with Tie2. IR-induced tyrosine phosphorylation of Tie2 was augmented by HSP25 overexpression; downstream events in the Tie2 signaling pathway, including phosphorylation of AKT and EKR1/2, were also activated. Conclusions: HSP25 protects against radiation-induced BM damage by interacting with and stabilizing Tie2. This may be a novel strategy for HSP25-mediated radioprotection in BM.

  16. Tocopherol succinate mobilized progenitors mitigate radiation-induced gastrointestinal injury in mice

    International Nuclear Information System (INIS)

    Singh, Vijay S.

    2012-01-01

    The goal of this study was to elucidate the role of a-tocopherol succinate (TS)-mobilized progenitors in mitigating the ionizing radiation-induced gastrointestinal (GI) syndrome in mice, We demonstrate the efficacy of a bridging-therapy which will allow the lymphohematopoietic system of severely immunocomprised victims exposed to ionizing radiation to recover from high doses of radiation. The hematopoietic progenitors in blood from TS-injected mice were analyzed by flow cytometry. CD2F1 mice were irradiated with a dose of radiation causing GI syndrome (11 Gy, cobalt-60 gamma-radiation) and then transfused intravenously (retro-orbital sinus) with whole blood or peripheral blood mononuclear cells (PBMC )from TS-injected mice 2, 24, or 48 h post-irradiation and monitored for 30-day survival, Jejunum sections were analyzed for tissue area, surviving crypts, villi, mitotic figures, basal lamina enterocytes, and apoptosis. Flow cytometric analysis of mobilized cells suggested that hematopoietic progenitors were mobilized from bone marrow into the peripheral blood of TS-injected mice, infusion of whole blood or PBMC from TS-injected mice significantly improved survival of mice receiving a high dose of radiation. Histopathology and immunostaining of jejunum from irradiated and TS-mobilized PBMC-transfused mice revealed significant protection of GI tissue from radiation injury, including inhibition of apoptosis. We demonstrate that TS mobilizes progenitors into peripheral circulation and that the infusion of mobilized progenitor-containing blood or PBMC acts as a bridging therapy for immune-system recovery in mice exposed to high, potentially fatal doses of ionizing radiation. (author)

  17. 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

  18. 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

  19. 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)

  20. Kinetics of radiation-induced segregation in ternary alloys

    International Nuclear Information System (INIS)

    Lam, N.Q.; 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

  1. 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)

  2. 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)

  3. 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

  4. 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.

  5. 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

  6. 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

  7. Accidental actions in steel structures

    NARCIS (Netherlands)

    Vrouwenvelder, A.C.W.M.; Gresnigt, A.M.

    2006-01-01

    Part 1-7 of EN 1991 covers accidental actions and gives rules and values for impact loads due to road, train and ship traffic and loads due to internal explosions. In this paper, the application of Part 1-7 of EN 1991 for steel structures is explained. Background information and design strategies

  8. Accidental Haemorrhage and Fetal Prognosis

    African Journals Online (AJOL)

    1974-04-17

    Apr 17, 1974 ... perinatal mortality associated with accidental haemorrhage. The importance of clinical signs in determining fetal ... presented with antepartum haemorrhage, and where a retroplacental clot was found postpartum. .... rupture of membranes and oxytocin infusion. This was done in spite of intra-uterine death in ...

  9. Accidental hypothermia-an update

    DEFF Research Database (Denmark)

    Paal, Peter; Gordon, Les; Strapazzon, Giacomo

    2016-01-01

    BACKGROUND: This paper provides an up-to-date review of the management and outcome of accidental hypothermia patients with and without cardiac arrest. METHODS: The authors reviewed the relevant literature in their specialist field. Summaries were merged, discussed and approved to produce this nar...

  10. Cellular therapy to treat ionizing radiation-induced cutaneous radiation syndrome: 2 cases report

    International Nuclear Information System (INIS)

    Benderitter, M.; Chapel, A.; Trompier, F.; Clairand, I.; Bottolier-Depois, J.F.; Gourmelon, P.; Bey, E.; Lataillade, J.J.

    2008-01-01

    Full Text: Localized irradiation at high dose exposition could induce severe radiation burns characterized by the occurrence of unpredictable successive inflammatory waves leading to the extension in surface and depth of necrotic processes. The medical management of these severe radiation burns remains today a challenging issue unresolved by the classical therapeutical approach. For the first time, two victims (accident of Chile, 2006 and accident of Senegal, 2007) accidentally exposed to an iridium gammagraphy radioactive source experienced a new and innovative therapeutic strategy combining dosimetry-guided surgery lesion excision and injection of MSC. The clinical evolution was remarkable. The clinical transfer of this therapeutic option was possible based on the research perform in the Institute and the IRSN/Percy hospital cooperation. Our data suggested that cellular therapy based on Mesenchymal Stem Cell (MSC) injection could be used to repair numerous injured tissues. We have studied the potential use of human MSC (hMSC) in order to limit radiation-induced skin lesions. Our pre-clinical data suggest a possible use of hMSC for the treatment of the early phase of the cutaneous radiation syndrome. The understanding of the precise healing mechanisms of hMSC in animal model is under investigation. These results will be helpful to generalize this innovative therapy to the treatment of other radiological complications. (author)

  11. 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.

  12. Modulation of radiation-induced life shortening by systemic intravenous MnSOD-plasmid liposome gene therapy.

    Science.gov (United States)

    Epperly, Michael W; Dixon, Tracy; Wang, Hong; Schlesselman, James; Franicola, Darcy; Greenberger, Joel S

    2008-10-01

    To determine whether systemic administration of MnSOD-PL protected mice from the acute hematopoietic syndrome and delayed death after total-body irradiation (TBI), C57BL/ 6J mice were injected intravenously with 100 microl liposomes containing 100 microg of human MnSOD-transgene plasmid 24 h prior to irradiation with 9.5 Gy or 1.0 Gy. The dose of 9.5 Gy was lethal to 42% of irradiated control female mice and 74% of irradiated control male mice at 30 days, with bone marrow hypocellularity consistent with the hematopoietic syndrome. A statistically significant increase in survival was observed in MnSOD-PL-treated female mice out to 400 days and in male mice out to 340 days. The incidence of tumors was similar between surviving groups. Between 350 and 600 days, the outcome was similar for both MnSOD-PL-treated and control irradiated groups, consistent with aging, with no difference in gross or microscopic pathological evidence of tumors. Male and female mice receiving 1.0 Gy TBI showed radiation-induced life shortening after 120 days that was decreased by MnSOD-PL administration and that was not associated with an increase in rate of tumor-associated death. Therefore, systemic MnSOD-PL radioprotective gene therapy is not associated with a detectably higher incidence of late carcinogenesis.

  13. Acute Renal Failure following Accidental Potassium Bromate ...

    African Journals Online (AJOL)

    Accidental poisoning is common in children. Potassium bromate is a commonly used additive and raising agent in many edibles particularly bread, a staple food worldwide, yet its accidental poisoning has hitherto, not been documented in Nigeria. We report an unusual case of acute renal failure following accidental ...

  14. 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)

  15. 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)

  16. Caffeine Markedly Enhanced Radiation-Induced Bystander Effects

    Science.gov (United States)

    Jiang, Erkang; Wu, Lijun

    2009-04-01

    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).

  17. 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).

  18. 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

  19. 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.

  20. 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

  1. 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

  2. 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

  3. [Symptoms and treatment of radiation-induced reactions].

    Science.gov (United States)

    Brzozowska, Anna; Idziak, Magdalena; Burdan, Franciszek; Mazurkiewicz, Maria

    2015-05-01

    Radiotherapy is one of the main methods of cancer treatment alone or in combination with chemotherapy. It is applied in about 60% of oncological patients. However, in spite of its clinical usefulness, radiotherapy is associated with a high risk of radiation-induced side effects, including dermatitis, enteritis, cystitis, pericarditis, pneumonia or depression, sexual function disorders, cardiomiopathy, coronary heart disease, anomalies of heart valves and development of second malignant tumor. The early diagnosis and proper treatment of radiation-induced side effects have a major impact on patients` quality of life and future prognosis. Radiation reactions can be categorized as acute or late, occurring before and after six months after radiotherapy. Among the most common acute reactions there were observed: skin rash, mucositis, nausea, vomiting, fever and radiation pneumonitis. Within reference to the late complications, we distinguish for instance fibrosis of organs, a radiation necrosis of bone, ulcers, fistulas, sexual dysfunction and the development of second malignant carcinomas. © 2015 MEDPRESS.

  4. 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)

  5. 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)

  6. 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

  7. 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.

  8. [Effects of thymosin alpha-1 on radiation-induced pneumonitis].

    Science.gov (United States)

    Yu, Rong; Sun, Yu; Cai, Qing; Li, Yongheng; Zhu, Guangying

    2011-03-01

    Radiation-induced lung injure is one of the major factors of limitation in radiotherapy for lung cancer. Whether the use of thymosin and radiotherapy simultaneously would increase the radiation-induced lung injure is unclear. The aim of this study is to evaluate the effects of thymosin alpha-1 on radiation induced pneumonitis in mice. Three groups of mice, control (C), radiation alone (RT), thymosin alpha-1 plus radiation (T+RT), were entered into the study. The weight and mortality of mice, pleural effusion, quantity of protein and cell count in the bronchoalvealar lavage (BAL) and pulmonary fibrosis score were evaluated as the outcome measures. The mortality ratio of the T+RT and RT groups were 3/14, 2/10, respectively. The time of death were all in the 23-24 weeks after radiotherapy. There was no pleural effusion in the T+RT group other than 2/2 occurred in RT group. The quantity of protein, cell number and neutrophil number in the BAL and lung coefficient in mice of T+RT group were remarkably lower than that of RT group, but the BALF macrophages number was remarkably higher than that in RT group in the 8 weeks. The quantity of protein, cell number, neutrophil number and macrophages number in the BAL, lung coefficient, the scores of lung fibrosis in mice of T+RT group were significantly lower than that of RT group in the 24 weeks. All test data were lowest in mice of C group. And there was no obvious pulmonary fibrosis in the mice of C group. Thymosin alpha-1 could relieve radiation-induced acute and late pulmonary injuries.

  9. 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.

  10. 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

  11. Radiation induced enterocolitis in uterine cervical cancer after radiotherapy

    International Nuclear Information System (INIS)

    Qin Risheng; Xu Lirong; Ye Shiqi; He Guilian; Li Jing; Wang Qiong

    2007-01-01

    Objective: To approach the cause of radiation induced enterocolitis and its relationship with retropostion of the uterus in uterine cervical cancer after radiotherapy. Methods: Twenty-two patients with radiation induced enterocolitis, from 212 patients with uterine cervical cancer who had received radio-therapy during 2002-2005, were retrospectively analyzed. The incidence between patients with anteposition and patients with retroposition of uterus was compared. The distance between uterine central axis and the rectum of 15 patients with anteposition and 15 patients with retroposition of the uterus was measured, as well as the uterus retroversional flexion angle of the retropositioned uterus. Results: The incidence of radiation enterocolitis in patients with retroposition of uterus was obviously higher than that in patients with anteposition (χ 2 =21.10, P<0.01). The distance between point C and the rectum in patients with retroposition of uterus was shorter(t=7.33, P<0.05). The retroversional flexion angle of retropostitioned uterus were between 9-22 degree with a median angle of 17 degree. Conclusion: The incidence of radiation induced enterocolitis is higher in patients with retropostition of uterus after radiotherapy, because the distance between the uterine central axis and the rectum is shorter. The y axis and z axis often form an acute angle in the rectal direction during after-loading therapy, which would had led to an excessive dose to the rectum. (authors)

  12. 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

  13. Radiation-Induced Differentiation in Human Lung Fibroblast

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sa-Rah; Ahn, Ji-Yeon; Han, Young-Soo; Shim, Jie-Young; Yun, Yeon-Sook; Song, Jie-Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2007-10-15

    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 {alpha}-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-{beta}), 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-{beta} 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-{beta} but also radiation can induce trans differentiation in human lung fibroblast WI-38 and IMR-90.

  14. Radiation-induced products of peptides and their enzymatic digestibility

    International Nuclear Information System (INIS)

    Gajewski, E.

    1983-01-01

    Chemical characterization of radiation-induced products of peptides and proteins is essential for understanding the effect of ionizing radiation on peptides and proteins. Furthermore, peptides containing radiation-altered amino acid residues might not be completely digestible by proteolytic enzymes. In this work, small homopeptides of Ala, Phe and Met were chosen as model peptides. Lysozyme was used to investigate the effect of ionizing radiation on a small protein. All peptides and lysozyme were irradiated in diluted, oxygen free, N 2 O-saturated aqueous solutions, using a 60 Co-γ-source. HPLC, capillary GC and GC-MS were applied to isolate and characterize the radiation-induced products. The enzymatic digestibility of the products was investigated using aminopeptidase M, leucine aminopeptidase, carboxypeptidase A and carboxypeptidase Y. It was found that irradiation of peptides examined in this work leads to racemization and alteration of amino acid residues and crosslinks between the peptide chains. In addition, it was established that exopeptidases act differently on radiation-induced dimers of peptides composed of aliphatic, aromatic and sulfur-containing amino acids

  15. 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

  16. A case of radiation induced leiomyosarcoma in the chest wall

    Energy Technology Data Exchange (ETDEWEB)

    Yamaoka, Norio; Uchiyama, Yoshitaka; Nakamura, Akihiro; Muraoka, Masashi; Kondou, Masamichi; Yamauchi, Hideto; Hashiyada, Hiroshi; Hashizume, Koji [Oita Prefectural Hospital (Japan)

    1995-08-01

    A case of radiation-induced leiomyosarcoma arising from the chest wall is reported. A 34-year-old man was admitted to the hospital because of an anterochest mass of 3 cm in diameter. He had been irradiated Liniac 6,000 rads for an invasive thymoma in the same area of the chest wall 6 years and 3 months before. A percutaneous needle biopsy of the mass indicated that it was histologically sarcoma. Chest CT scan visualized that the tumor localized in the chest wall. Wide en-bloc excision of the whole chest wall was performed. Histological diagnosis of leiomyosarcoma arising from the chest wall was made. He died of local recurrence one year and 6 months after the operation. Our case was fulfilled the diagnostic criteria of Cahan`s radiation-induced sarcoma. Radiation-induced leiomyosarcoma rarely occurs. A total of 10 cases including this case have been reported in the Japanese and foreign literature, which are also discussed and reviewed. (author).

  17. A case of radiation induced leiomyosarcoma in the chest wall

    International Nuclear Information System (INIS)

    Yamaoka, Norio; Uchiyama, Yoshitaka; Nakamura, Akihiro; Muraoka, Masashi; Kondou, Masamichi; Yamauchi, Hideto; Hashiyada, Hiroshi; Hashizume, Koji

    1995-01-01

    A case of radiation-induced leiomyosarcoma arising from the chest wall is reported. A 34-year-old man was admitted to the hospital because of an anterochest mass of 3 cm in diameter. He had been irradiated Liniac 6,000 rads for an invasive thymoma in the same area of the chest wall 6 years and 3 months before. A percutaneous needle biopsy of the mass indicated that it was histologically sarcoma. Chest CT scan visualized that the tumor localized in the chest wall. Wide en-bloc excision of the whole chest wall was performed. Histological diagnosis of leiomyosarcoma arising from the chest wall was made. He died of local recurrence one year and 6 months after the operation. Our case was fulfilled the diagnostic criteria of Cahan's radiation-induced sarcoma. Radiation-induced leiomyosarcoma rarely occurs. A total of 10 cases including this case have been reported in the Japanese and foreign literature, which are also discussed and reviewed. (author)

  18. Post accidental small breaks analysis

    International Nuclear Information System (INIS)

    Depond, G.; Gandrille, J.

    1980-04-01

    EDF ordered to FRAMATOME by 1977 to complete post accidental long term studies on 'First Contrat-Programme' reactors, in order to demonstrate the safety criteria long term compliance, to get information on NSSS behaviour and to improve the post accidental procedures. Convenient analytical models were needed and EDF and FRAMATOME respectively developped the AXEL and FRARELAP codes. The main results of these studies is that for the smallest breaks, it is possible to manually undertake cooling and pressure reducing actions by dumping the steam generators secondary side in order to meet the RHR operating specifications and perform long term cooling through this system. A specific small breaks procedure was written on this basis. The EDF and FRAMATOME codes are continuously improved; the results of a French set of separate effects experiments will be incorporated as well as integral system verification

  19. 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

  20. Modulation of radiation induced DNA damage by natural products in hemopoietic tissue of mice

    International Nuclear Information System (INIS)

    Jayakumar, S.; Bhilwade, H.N.; Chaubey, R.C.

    2014-01-01

    from the radiation induced DNA damage in spleenocytes. The data on DNA damage analysis by comet assay also showed significant reduction in radiation induced DNA damage in peripheral blood leukocytes of mice pre-treated with taurine. (author)

  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. 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

  3. 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

  4. Effects of Thymosin Alpha-1 on Radiation-induced Pneumonitis

    Directory of Open Access Journals (Sweden)

    Rong YU

    2011-03-01

    Full Text Available Background and objective Radiation-induced lung injure is one of the major factors of limitation in radiotherapy for lung cancer. Whether the use of thymosin and radiotherapy simultaneously would increase the radiationinduced lung injure is unclear. The aim of this study is to evaluate the effects of thymosin alpha-1 on radiation induced pneumonitis in mice. Methods Three groups of mice, control (C, radiation alone (RT, thymosin alpha-1 plus radiation (T+RT, were entered into the study. The weight and mortality of mice, pleural effusion, quantity of protein and cell count in the bronchoalvealar lavage (BAL and pulmonary fibrosis score were evaluated as the outcome measures. Results The mortality ratio of the T+RT and RT groups were 3/14, 2/10, respectively. The time of death were all in the 23-24 weeks after radiotherapy. There was no pleural effusion in the T+RT group other than 2/2 occured in RT group. The quantity of protein, cell number and neutrophil number in the BAL and lung coefficient in mice of T+RT group were remarkably lower than that of RT group, but the BALF macrophages number was remarkably higher than that in RT group in the 8 weeks. The quantity of protein, cell number, neutrophil number and macrophages number in the BAL, lung coefficient, the scores of lung fibrosis in mice of T+RT group were significantly lower than that of RT group in the 24 weeks. All test data were lowest in mice of C group. And there was no obvious pulmonary fibrosis in the mice of C group. Conclusion Thymosin alpha-1 could relieve radiation-induced acute and late pulmonary injuries.

  5. '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

  6. 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)

  7. 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

  8. 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

  9. 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.)

  10. Radiation induced degradation of some crystalline amino acids

    International Nuclear Information System (INIS)

    Gejvall, T.; Loefroth, G.

    1975-01-01

    The gamma-radiation induced degradation of five crystalline DL-amino acids, leucine, isoleucine, norleucine, valine, and norvaline, has been quantitatively studied. The major products are carboxylic acids formed by deamination of the amino acids, ammonia, amines formed by decarboxylation of the amino acids, and carbon dioxide. In addition, carbonyl compounds and amides, plus small amounts of hydrogen gas and various hydrocarbons have been detected. The total degradation, (-M), has been determined (by isotope dilution) to be 8 for valine and 14 for leucine. (author)

  11. Radiation-induced inhibition of RNA synthesis in Tetrahymena pyriformis

    International Nuclear Information System (INIS)

    Ernst, S.G.; Rustad, R.C.; Oleinick, N.L.

    1975-01-01

    Radiation-induced disturbances in RNA synthesis were investigated in exponentially growing Tetrahymena. Sub-lethal doses of γ-radiation lead to a transient, dose-dependent decrease in the rate of total RNA synthesis measured by 3 H-uridine incorporation, without an alteration of 3 H-uridine uptake by the cells. The rate of 3 H-uridine incorporation decreased exponentially with dose. In contrast, the duration of inhibition of RNA synthesis was linearly dependent on dose. Target-theory calculations suggest that the sensitive molecule has a molecular weight of about 2x10 7 Daltons. (author)

  12. 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

  13. 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

  14. Accidental poisoning with autumn crocus.

    Science.gov (United States)

    Gabrscek, Lucija; Lesnicar, Gorazd; Krivec, Bojan; Voga, Gorazd; Sibanc, Branko; Blatnik, Janja; Jagodic, Boris

    2004-01-01

    We describe a case of a 43-yr-old female with severe multiorgan injury after accidental poisoning with Colchicum autumnale, which was mistaken for wild garlic (Allium ursinum). Both plants grow on damp meadows and can be confused in the spring when both plants have leaves but no blossoms. The autumn crocus contains colchicine, which inhibits cellular division. Treatment consisted of supportive care, antibiotic therapy, and granulocyte-directed growth factor. The patient was discharged from the hospital after three weeks. Three years after recovery from the acute poisoning, the patient continued to complain of muscle weakness and intermittent episodes of hair loss.

  15. Mortalidad intrahospitalaria por accidente cerebrovascular

    OpenAIRE

    Federico Rodríguez Lucci; Virginia Pujol Lereis; Sebastián Ameriso; Guillermo Povedano; María F. Díaz; Alejandro Hlavnicka; Néstor A. Wainsztein; Sebastián F. Ameriso

    2013-01-01

    La mortalidad global por accidente cerebrovascular (ACV) ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Str...

  16. Accidental Decannulation OF TRACHEOSTOMY TUBES - Case Series

    OpenAIRE

    Omokanye, HK; Dunmade, AD; Segun-Busari, S; Afolabi, OA; Habeeb, OG; Adegboye, MB; Alabi, BS

    2016-01-01

    Tracheostomy tube (TT) is usually removed in a planned manner once the patient ceases to have the condition that necessitated the procedure. Accidental decannulation or extubation refers to inadvertent removal of tracheostomy tube out of the stoma. It could prove fatal in an otherwise stable patient. We review a variety of unexpected and often-overlooked causes of accidental decannulation with suggestions on preventive measures. We therefore present three cases of accidental decannulation of ...

  17. Comportamiento de los accidentes laborales

    Directory of Open Access Journals (Sweden)

    Miguel Gómez Vital

    1999-01-01

    Full Text Available Se realiza una valoración sobre la situación de la accidentalidad en centros de trabajo de la provincia de Villa Clara de 1993 a 1997. El total de accidentes registrados fue de 12 522. Últimamente han disminuido y su índice de incidencia. En el último año se redujo el promedio de días perdidos, pero el índice de gravedad alcanzó la cifra mayor. Se insiste en el cumplimiento del programa de prevención y reducción de accidentes laborales.The situation of the occupational accidents that occurred in the province of Villa Clara from 1993 to 1997 was assessed. 12 522 accidents were registered during that periods. A decrease of these accidents and of their incidence rate has been observed lately. The average of lost days was reduced during the last year, out the severity index reached the highest figure. Emphasis is made on the importance of fulfilling the program of prevention and reduction of occupational accidents.

  18. 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

  19. 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.)

  20. 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)

  1. Radiation-induced cataracts. Glance at some new data

    International Nuclear Information System (INIS)

    The radiation-induced cataract has been up to now considered as a quite rare pathology, needing high-dose radiations (beyond a dose threshold roughly estimated at 2 Grays to the lens) consisting mainly in head tumour radiotherapy complications. Several new studies on different exposed populations such as astronauts, Japanese atomic bomb survivors, people undergoing X-ray examinations, Chernobyl accident 'liquidators' as well as data from animal experiments, suggest that dose threshold for detectable opacities as well as for clinical posterior sub-capsular cataract occurring, might be far lower than those previously assumed. Even the existence of a dose threshold is no longer an absolute certitude insofar as radiation-induced cataract pathogenesis might consist not really in a deterministic effect (direct tissue harmful effect, killing or seriously injuring a critical population of cells) as believed until now, but rather in a stochastic effect (genomic damage in target-cells, altered cell division, abnormal lens fibre cell differentiation). More practically, these new data may lead us to reconsider radioprotection of specifically exposed populations : mainly patients and workers. Regarding workers, labour legislation (lens equivalent dose limit of 150 mSv during 12 consecutive months) might be, in the medium term, reassessed downwards. (author)

  2. 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)

  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. 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)

  5. 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)

  6. 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.)

  7. The Role of Radiation Induced Injury on Lung Cancer

    Directory of Open Access Journals (Sweden)

    Stephanie Puukila

    2017-07-01

    Full Text Available This manuscript evaluates the role of cell killing, tissue disorganization, and tissue damage on the induction of lung cancer following low dose rate radiation exposures from internally deposited radioactive materials. Beagle dogs were exposed by inhalation to 90Y, 91Y, 144Ce, or 90Sr in fused clay particles. Dogs lived out their life span with complete pathology conducted at the time of death. The radiation dose per cell turnover was characterized and related to the cause of death for each animal. Large doses per cell turnover resulted in acute death from lung damage with extensive cell killing, tissue disorganization, chronic inflammatory disease, fibrosis, and pneumonitis. Dogs with lower doses per cell turnover developed a very high frequency of lung cancer. As the dose per cell turnover was further decreased, no marked tissue damage and no significant change in either life span or lung cancer frequency was observed. Radiation induced tissue damage and chronic inflammatory disease results in high cancer frequencies in the lung. At doses where a high frequency of chromosome damage and mutations would be predicted to occur there was no decrease in life span or increase in lung cancer. Such research suggests that cell killing and tissue damage and the physiological responses to that damage are important mechanisms in radiation induced lung cancer.

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

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sa Rah; Ahn, Ji Yeon; Kim, Mi Hyeung; Lim, Min Jin; Yun, Yeon Sook; Song, Jie Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2009-05-15

    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.

  9. 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

  10. Radiation-induced cationic polymerization of vinyl ethers in solution

    International Nuclear Information System (INIS)

    Deffieux, A.; Young, J.A.; Hsieh, W.C.; Squire, D.R.; Stannett, V.

    1983-01-01

    The influences of the polymerization media, the monomer and solvent concentrations and the temperature on the radiation-induced polymerization of isopropyl vinyl ether (IPVE) have been studied in detail under super-dry conditions. Rates of polymerization were measured and estimates of the rate constants of polymerization were calculated according to the simplified Hayashi-Williams equation. A comparison of the results with those previously reported for ethyl vinyl ether (EVE) is made. The much higher reactivity of IPVC in low polar solvents is interpreted by a drastic reduction of the polymer intramolecular solvation of the growing chain ends. This is ascribed to the bulkiness of the isopropyl side-chain groups. The radiation-induced polymerization of IPVE in bulk and in various solvents with different physical and solvating properties was studied. This was to obtain further information on the kinetics and the mechanisms involved with this monomer and also the role of the polymerization media. The influence of the monomer and solvent concentrations and of the polymerization temperature on the rate of polymerization have also been investigated. (author)

  11. 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.)

  12. 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.

  13. Study on the piezoresistivity of radiation-induced point defects

    International Nuclear Information System (INIS)

    Cochard, Andre.

    1976-06-01

    This study is made of two distinct part. In a first part experimental results on the elastoresistivity of radiation-induced point defects in gold are presented. A comparison with the results on copper and molybdenum confirms the exceptional annealing behavior of gold. However, as for copper, only interstitials contribute to elastoresistivity. The results can be understood if the elastoresistivity on gold is associated to Frenkel defects. In a second part an experimental set up is described allowing the dynamic measurement of the piezoresistivity associated to radiation-induced point defects. Experiments were carried out on pure copper and Al-Cu alloys. It is shown that both, the modulus and the phase angle of the complex piezoresistivity have to be measured simultaneously. The thermoelastic effect, a phenomenon due to temperature changes in the sample under rapidly varying strain was studied as a function of strain amplitude and frequency. A simple theory of this effect yields a correct description of the experimental results [fr

  14. 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

  15. Hematopoietic stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Eleftheria Hatzimichael

    2010-08-01

    Full Text Available Eleftheria Hatzimichael1, Mark Tuthill21Department of Haematology, Medical School of Ioannina, University of Ioannina, Ioannina, Greece; 2Department of Medical Oncology, Hammersmith Hospital, Imperial College National Health Service Trust, London, UKAbstract: More than 25,000 hematopoietic stem cell transplantations (HSCTs are performed each year for the treatment of lymphoma, leukemia, immune-deficiency illnesses, congenital metabolic defects, hemoglobinopathies, and myelodysplastic and myeloproliferative syndromes. Before transplantation, patients receive intensive myeloablative chemoradiotherapy followed by stem cell “rescue.” Autologous HSCT is performed using the patient’s own hematopoietic stem cells, which are harvested before transplantation and reinfused after myeloablation. Allogeneic HSCT uses human leukocyte antigen (HLA-matched stem cells derived from a donor. Survival after allogeneic transplantation depends on donor–recipient matching, the graft-versus-host response, and the development of a graft versus leukemia effect. This article reviews the biology of stem cells, clinical efficacy of HSCT, transplantation procedures, and potential complications.Keywords: hematopoietic stem cell transplantation, complications

  16. Protective role of Carica papaya (Linn.) in electron beam radiation induced hematological and cytogenetic damages in Swiss albino mice

    International Nuclear Information System (INIS)

    Yogish Somayaji, T.; Suchetha Kumari, N.

    2014-01-01

    Carica papaya (Linn.) is known to possess various biomedical applications. It has remarkable antioxidant properties. The main objective of the study was to evaluate the leaf extracts of Carica papaya (Linn.) on hematologic and cytogenetic changes occurring due to irradiation of mice to sub-lethal doses of Electron Beam Radiation (EBR). Analysis of hematological changes occurring due to irradiation of mice to sub-lethal doses of EBR, and the effects of Carica papaya (Linn.) extract on the same. The Assessment of hematopoietic stress by spleen colony forming unit and spleen body weight index. The analysis of cell proliferation and immunomodulation with response to the effects of Carica papaya (Linn.) extract by estimation of IL-6. The estimation of serum total antioxidants, lipid peroxidation and analyzing the activities of enzymes like SOD, ALP, and AST. Male Swiss albino mice were fed orally with papaya aqueous leaf extract for 15 days. They were irradiated with a whole body dose of 6 Gy Electron Beam radiation. The mice were dissected for liver, kidney, bone marrow, spleen and brain. The hematological studies were done using blood cell count in an automated cell counter. The biochemical estimations like urea, creatinine, SGOT, SGPT, Total Protein, Albumin, Bilirubin were done using the serum and homogenates. The total antioxidant capacity, the antioxidant enzymes were estimated. The Interleukin-6 levels were estimated in serum to assess immune modulation. The results show a decrease in the hematological parameters in radiated animals. The papaya treated groups have shown modulation in the hematological parameters. The extract has also reduced the suppression of the bone marrow induced by radiation. The radiation induced liver damage is also reduced in papaya treated groups. The aqueous extract of Carica papaya (Linn.) has shown protective effects in electron beam radiation induced tissue damages in Swiss Albino mice (author)

  17. Radioprotective effect of methanolic root extract of Loeseneriella arnottiana on radiation induced DNA damage in human lymphocytes in vitro

    International Nuclear Information System (INIS)

    Prajna, P.S.

    2012-01-01

    Intense exposure to ionization radiation by accidental, occupational or therapeutical purpose causes cellular damage mainly by formation of excessive reactive oxygen species (ROS) or by free radicals. Humans are intentionally exposed to ionising radiation for diagnostic or therapeutic purposes. The use of ionising radiation in cancer therapy may lead to transient and/or permanent injury to normal tissues within the treatment field. To increase the therapeutic index of radiation therapy, various modes of radioprotection have been developed that selectively reduce cytotoxic effects to normal tissues. Because radiation-induced cellular damage is attributed primarily to the harmful effects of free radicals, molecules with radical scavenging properties are particularly promising as radioprotectors. Loeseneriella arnottiana, a member of family Hippocrateaceae, is a climbing shrub used by traditional medicine practitioners. To study the antioxidant activity and radioprotective effect of methanolic root extract of Loeseneriella arnottiana against electron beam radiation induced DNA damage in human lymphocytes. Loeseneriella arnottiana roots were dried and extracted using methanol by solvent extraction method. Antioxidant activity was measured by DPPH method. DNA damage was assessed by comet assay parameters. The lymphocytes were incubated for one hour with two different concentrations 10 μg and 50 μg of root extract before exposure to 2 Gy electron beam radiation. 30 μg of methanolic root extract of Loeseneriella arnottiana exhibited 96% radical scavenging activity comparable to 15 μg of ascorbic acid. In reducing power assay it showed dose dependent increase in absorbance indicating that extract is capable of donating hydrogen atoms. Pretreatment of lymphocytes with 10 μg and 50 μg of root extract before irradiation resulted in reduction in the Comet length, Olive tail moment, percentage of DNA in tail when compared to the radiation control group. Results of this

  18. Radiation induced genome instability: multiscale modelling and data analysis

    Science.gov (United States)

    Andreev, Sergey; Eidelman, Yuri

    2012-07-01

    Genome instability (GI) is thought to be an important step in cancer induction and progression. Radiation induced GI is usually defined as genome alterations in the progeny of irradiated cells. The aim of this report is to demonstrate an opportunity for integrative analysis of radiation induced GI on the basis of multiscale modelling. Integrative, systems level modelling is necessary to assess different pathways resulting in GI in which a variety of genetic and epigenetic processes are involved. The multilevel modelling includes the Monte Carlo based simulation of several key processes involved in GI: DNA double strand breaks (DSBs) generation in cells initially irradiated as well as in descendants of irradiated cells, damage transmission through mitosis. Taking the cell-cycle-dependent generation of DNA/chromosome breakage into account ensures an advantage in estimating the contribution of different DNA damage response pathways to GI, as to nonhomologous vs homologous recombination repair mechanisms, the role of DSBs at telomeres or interstitial chromosomal sites, etc. The preliminary estimates show that both telomeric and non-telomeric DSB interactions are involved in delayed effects of radiation although differentially for different cell types. The computational experiments provide the data on the wide spectrum of GI endpoints (dicentrics, micronuclei, nonclonal translocations, chromatid exchanges, chromosome fragments) similar to those obtained experimentally for various cell lines under various experimental conditions. The modelling based analysis of experimental data demonstrates that radiation induced GI may be viewed as processes of delayed DSB induction/interaction/transmission being a key for quantification of GI. On the other hand, this conclusion is not sufficient to understand GI as a whole because factors of DNA non-damaging origin can also induce GI. Additionally, new data on induced pluripotent stem cells reveal that GI is acquired in normal mature

  19. 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

  20. 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

  1. 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

  2. Accidental Poisoning with Otapiapia: a Local Organophasphate ...

    African Journals Online (AJOL)

    Children are prone to accidental poisoning. We report this fatal organophosphate poisoning of a 3-year-old Nigerian boy following accidental ingestion of a homemade cocktail of kerosene and 'Otapiapia': a local rodenticide to highlight the dangers inherent in un-regulated production, home use and storage of this ...

  3. Tension Pneumothorax following an Accidental Kerosene Poisoning ...

    African Journals Online (AJOL)

    Tension pneumothorax is a rare complication following an accidental kerosene poisoning. In such situation, a bed-side needle thoracocentesis is performed because of its potential of becoming fatal; hence its clinical importance. A case of 15 month old boy with tension pneumothorax following accidental kerosene ...

  4. About Assessment Criteria of Driver's Accidental Abilities

    Science.gov (United States)

    Lobanova, Yuliya I.; Glushko, Kirill V.

    2016-01-01

    The article points at the importance of studying the human factor as a cause of accidents of drivers, especially in loosely structured traffic situations. The description of the experiment on the measurement of driver's accidental abilities is given. Under accidental ability is meant the capability to ensure the security of driving as a behavior…

  5. Characterisation of childhood and adolescence accidental fatalities ...

    African Journals Online (AJOL)

    Background: Accidental death in childhood and adolescence is posing a public health problem in Nigeria, as most of these deaths were not caused by the victims. There is need to research into the pattern and circumstances surrounding the death. Aim: To characterise and study accidental deaths in childhood and ...

  6. Separation functional fibers by radiation induced graft polymerization and application

    International Nuclear Information System (INIS)

    Fujiwara, K.

    2007-01-01

    Commercially available non-woven fabric made of polyolefines was used as trunk polymer for radiation induced graft polymerization (RIGP). Ion exchange, antimicrobial and catalytic function was introduced on the fabric by RIGP. All of these materials are commercialized. Ion exchange fabric prepared by RIGP are applied for chemical filter to remove ionic impurities in semiconductor factory and are also applied for continuous de-ionization apparatus to make pure water in combination with ion conductive spacer. Polyvinylpyrrolidone-iodide grafted fabric was produced as antimicrobial fabric and applied for mask. Metal oxide nanoparticle was immobilized onto the ion exchange fabric. This material has catalytic function and was applied for the removal of ozone from air. In all of these applications, long sheets of non-woven fabrics are applied as a trunk polymer. Manufacturing process of RIGP for long sheet is also reported here

  7. 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.)

  8. 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)

  9. 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).

  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. Radiation Induced Cystitis and Proctitis - Prediction, Assessment and Management.

    Science.gov (United States)

    Mallick, Supriya; Madan, Renu; Julka, Pramod K; Rath, Goura K

    2015-01-01

    Cystitis and proctitis are defined as inflammation of bladder and rectum respectively. Haemorrhagic cystitis is the most severe clinical manifestation of radiation and chemical cystitis. Radiation proctitis and cystitis are major complications following radiotherapy. Prevention of radiation-induced haemorrhagic cystitis has been investigated using various oral agents with minimal benefit. Bladder irrigation remains the most frequently adopted modality followed by intra-vesical instillation of alum or formalin. In intractable cases, surgical intervention is required in the form of diversion ureterostomy or cystectomy. Proctitis is more common in even low dose ranges but is self-limiting and improves on treatment interruption. However, treatment of radiation proctitis is broadly non-invasive or invasive. Non-invasive treatment consists of non-steroid anti-inflammatory drugs (NSAIDs), anti-oxidants, sucralfate, short chain fatty acids and hyperbaric oxygen. Invasive treatment consists of ablative procedures like formalin application, endoscopic YAG laser coagulation or argon plasma coagulation and surgery as a last resort.

  12. Factors that modify risks of radiation-induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    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).

  13. Melting and glass transition of radiation-induced graft polyethylene

    International Nuclear Information System (INIS)

    Toi, K.; Kikuchi, M.; Tokuda, T.

    1977-01-01

    Melting and glass transition data are reported employing DSC for styrene-grafted high-density polyethylene obtained by γ radiation. Judging from the data of the melting point and the heat of fusion, the grafted polystyrene had no effect on the polyethylene crystallites, but the half-width of the thermogram was observed to increase slightly, showing an effect on the crystallite size distribution. As no effect was observed on the glass transition temperature by grafting, the amorphous region of the polyethylene apparently was not affected. It is suggested, therefore, that the free volume or segmental mobility will not be decreased by radiation-induced grafting. Very few but long grafted chains had negligible effect on the average polyethylene chain length available for segmental motion, and grafted polystyrene should be expected to differ from the styrene homopolymer in thermal motions

  14. 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

  15. Separation functional fibers by radiation induced graft polymerization and application

    Science.gov (United States)

    Fujiwara, K.

    2007-12-01

    Commercially available non-woven fabric made of polyolefines was used as trunk polymer for radiation induced graft polymerization (RIGP). Ion exchange, antimicrobial and catalytic function was introduced on the fabric by RIGP. All of these materials are commercialized. Ion exchange fabric prepared by RIGP are applied for chemical filter to remove ionic impurities in semiconductor factory and are also applied for continuous de-ionization apparatus to make pure water in combination with ion conductive spacer. Polyvinylpyrrolidone-iodide grafted fabric was produced as antimicrobial fabric and applied for mask. Metal oxide nanoparticle was immobilized onto the ion exchange fabric. This material has catalytic function and was applied for the removal of ozone from air. In all of these applications, long sheets of non-woven fabrics are applied as a trunk polymer. Manufacturing process of RIGP for long sheet is also reported here.

  16. Ventricular tachycardia associated with radiation-induced cardiac sarcoma.

    Science.gov (United States)

    Beaty, Elijah H; Ballany, Wassim; Trohman, Richard G; Madias, Christopher

    2014-12-01

    Cardiac tumors can lead to distinct electrocardiographic changes and ventricular arrhythmias. Benign and malignant cardiac tumors have been associated with ventricular tachycardia. When possible, benign tumors should be resected when ventricular arrhythmias are intractable. Chemotherapy can shrink malignant tumors and eliminate arrhythmias. We report the case of a 52-year-old woman with breast sarcoma whom we diagnosed with myocardial metastasis after she presented with palpitations. The initial electrocardiogram revealed sinus rhythm with new right bundle branch block and ST-segment elevation in the anterior precordial leads. During telemetry, hemodynamically stable, sustained ventricular tachycardia with right ventricular localization was detected. Images showed a myocardial mass in the right ventricular free wall. Amiodarone suppressed the arrhythmia. To our knowledge, this is the first report of ventricular tachycardia associated with radiation-induced undifferentiated sarcoma. We discuss the distinct electrocardiographic changes and ventricular arrhythmias that can be associated with cardiac tumors, and we review the relevant medical literature.

  17. 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.

  18. Cell cycle regulation and radiation-induced cell death

    International Nuclear Information System (INIS)

    Favaudon, V.

    2000-01-01

    Tight control of cell proliferation is mandatory to prevent cancer formation as well as to normal organ development and homeostasis. This occurs through checkpoints that operate in both time and space and are involved in the control of numerous pathways including DNA replication and transcription, cell cycle progression, signal transduction and differentiation. Moreover, evidence has accumulated to show that apoptosis is tightly connected with the regulation of cell cycle progression. In this paper we describe the main pathways that determine checkpoints in the cell cycle and apoptosis. It is also recalled that in solid tumors radiation-induced cell death occurs most frequently through non-apoptotic mechanisms involving oncosis, and mitotic or delayed cell death. (author)

  19. 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

  20. Radiation-Induced Heart Disease: Pathologic Abnormalities and Putative Mechanisms

    Directory of Open Access Journals (Sweden)

    Neil K Taunk

    2015-02-01

    Full Text Available Breast cancer is a common diagnosis in women. Breast radiation has become a critical in managing patients who receive breast conserving surgery, or have certain high-risk features after mastectomy. Most patients have an excellent prognosis, therefore understanding the late effects of radiation to the chest is important. Radiation induced heart disease (RIHD comprises a spectrum of cardiac pathology including myocardial fibrosis and cardiomyopathy, coronary artery disease, valvular disease, pericardial disease, and arrhythmias. Tissue fibrosis is a common mediator in RIHD. Multiple pathways converge with both acute and chronic cellular, molecular, and genetic changes to result in fibrosis. In this article, we review the pathophysiology of cardiac disease related to radiation therapy to the chest. Our understanding of these mechanisms has improved substantially, but much work remains to further refine radiation delivery techniques and develop therapeutics to battle late effects of radiation.

  1. Radiation-induced mucositis pain in mesopharyngeal and hypopharyngeal cancer

    International Nuclear Information System (INIS)

    Takahashi, Atsuhito; Shoji, Kazuhiko; Mizuta, Masanobu; Matsubara, Mami; Iki, Takehiro

    2010-01-01

    Radiation therapy in head and neck malignancy often triggers painful mucositis poorly controlled by nonsteroidal antiinflammatory drugs (NSAIDs). To better understand how radiation-induced pain develops over time, we studied numerical rating scale (NRS 0-5) pain scores in 27 subjects undergoing 60-72 Gy radiation therapy for newly diagnosed cancer- 13 with mesopharynx and 14 with hypopharynx. Mucositis severity was evaluated using Common Terminology Criteria for Adverse Events version 3.0 (CTCAE v3.0) based on mucositis pain, analgesic administration, and oral feedings of our subjects, with 8 mesopharyngeal and 10 with hypopharyngeal cancer had been pain-free before radiation therapy. The mucositis and pain course was severer in mesopharyngeal than in hypopharyngeal cancer. NSAIDs and opioid use was similar in both cancer types, which also required tube feeding in 7 subjects (38.9%). (author)

  2. 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)

  3. 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.

  4. γ-radiation-induced solution polymerization of some methyl aryloxymethacrylates

    International Nuclear Information System (INIS)

    Devarajan, Ramaswamy; Balakrishnan, Thaikkannu; Santappa, M.; Viswanathan, Balasubramanian.

    1981-01-01

    The kinetics of γ-radiation-induced solution polymerization of methyl phenoxymethacrylate (MPMA) and methyl p-cresoxymethacrylate (MCMA) in toluene has been studied at 30 and 0 0 C and at dose rates of 0.3, 0.15, and 0.75 Mrad h -1 . The rates of polymerization, which were found to increase with increasing monomer concentration, have direct dependence on dose rate and [monomer] and have inverse dependence on [solvent]. The apparent energies of activation measured at 0.3 Mrad h -1 for MPMA and MCMA respectively are: 46.8 kJ mol -1 and 11.7 kJ mol -1 . The polymerization proceeded in spite of the presence of the inhibitor p-hydroxyphenyl methyl ether (PHME). This suggests that the mechanism of polymerization may be predominantly ionic. A suitable reaction scheme has been proposed. (author)

  5. 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

  6. Two cases of radiation-induced sarcoma (RIS) after mastectomy

    International Nuclear Information System (INIS)

    Mayama, Satoshi; Tamura, Gen; Akasaka, Toshihide; Kon, Saiichi; Ishida, Motoo; Saitoh, Kazuyoshi

    1990-01-01

    Two cases of radiation-induced sarcoma (RIS) appearing after mastectomy were reported. First case; 51-year-old female. She was irradiated with 42 Gy rads Linac after mastectomy for breast cancer. Seven years later, fibrosarcoma appeared and she died of the complications after two years. Second case; 59-year-old female. She was irradiated with 80 Gy 60 Co after mastectomy for breast cancer. Twenty-five years later, malignant fibrous histyocytoma appeared. The patient has been well for two years although the tumor once recurred locally. The occurrence rate of RIS after mastectomy is approaching 1% in our hospital. The cases which receive additional radiation therapy after the conservative surgery for localized breast cancer have been on the increase. Therefore, the radiation therapy should be carried out for appropriate patients, and if it is performed, long-term follow-up is necessary. (author)

  7. 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.)

  8. Accidental Decannulation OF TRACHEOSTOMY TUBES - Case Series.

    Science.gov (United States)

    Omokanye, H K; Dunmade, A D; Segun-Busari, S; Afolabi, O A; Habeeb, O G; Adegboye, M B; Alabi, B S

    2016-01-01

    Tracheostomy tube (TT) is usually removed in a planned manner once the patient ceases to have the condition that necessitated the procedure. Accidental decannulation or extubation refers to inadvertent removal of tracheostomy tube out of the stoma. It could prove fatal in an otherwise stable patient. We review a variety of unexpected and often-overlooked causes of accidental decannulation with suggestions on preventive measures. We therefore present three cases of accidental decannulation of tracheostomy tubes in order to report our experiences in the management of the condition. Accidental decannulation occurs both in hospitalized and patient on home care of their tracheostomy tubes. Reduction in neck circumference due to weight loss predisposes to accidental decannulation, which could be prevented by suturing the flange to the skin.

  9. 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.

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

    International Nuclear Information System (INIS)

    Jiravova, M.

    2012-01-01

    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

  11. Bystander effects in radiation-induced genomic instability

    Science.gov (United States)

    Morgan, William F.; Hartmann, Andreas; Limoli, Charles L.; Nagar, Shruti; Ponnaiya, Brian

    2002-01-01

    Exposure of GM10115 hamster-human hybrid cells to X-rays can result in the induction of chromosomal instability in the progeny of surviving cells. This instability manifests as the dynamic production of novel sub-populations of cells with unique cytogenetic rearrangements involving the "marker" human chromosome. We have used the comet assay to investigate whether there was an elevated level of endogenous DNA breaks in chromosomally unstable clones that could provide a source for the chromosomal rearrangements and thus account for the persistent instability observed. Our results indicate no significant difference in comet tail measurement between non-irradiated and radiation-induced chromosomally unstable clones. Using two-color fluorescence in situ hybridization we also investigated whether recombinational events involving the interstitial telomere repeat-like sequences in GM10115 cells were involved at frequencies higher than random processes would otherwise predict. Nine of 11 clones demonstrated a significantly higher than expected involvement of these interstitial telomere repeat-like sequences at the recombination junction between the human and hamster chromosomes. Since elevated levels of endogenous breaks were not detected in unstable clones we propose that epigenetic or bystander effects (BSEs) lead to the activation of recombinational pathways that perpetuate the unstable phenotype. Specifically, we expand upon the hypothesis that radiation induces conditions and/or factors that stimulate the production of reactive oxygen species (ROS). These reactive intermediates then contribute to a chronic pro-oxidant environment that cycles over multiple generations, promoting chromosomal recombination and other phenotypes associated with genomic instability.

  12. Role of Oxidative Damage in Radiation-Induced Bone Loss

    Science.gov (United States)

    Schreurs, Ann-Sofie; Alwood, Joshua S.; Limoli, Charles L.; Globus, Ruth K.

    2014-01-01

    used an array of countermeasures (Antioxidant diets and injections) to prevent the radiation-induced bone loss, although these did not prevent bone loss, analysis is ongoing to determine if these countermeasure protected radiation-induced damage to other tissues.

  13. 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

  14. Chronic radiation-induced dermatitis: challenges and solutions

    Directory of Open Access Journals (Sweden)

    Spałek M

    2016-12-01

    Full Text Available Mateusz Spałek Department of Radiotherapy I, The Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw, Poland Abstract: Chronic radiation dermatitis is a late side effect of skin irradiation, which may deteriorate patients’ quality of life. There is a lack of precise data about its incidence; however, several risk factors may predispose to the development of this condition. It includes radiotherapy dose, fractionation, technique, concurrent systemic therapy, comorbidities, and personal and genetic factors. Chronic radiation dermatitis is mostly caused by the imbalance of proinflammatory and profibrotic cytokines. Clinical manifestation includes changes in skin appearance, wounds, ulcerations, necrosis, fibrosis, and secondary cancers. The most severe complication of irradiation is extensive radiation-induced fibrosis (RIF. RIF can manifest in many ways, such as skin induration and retraction, lymphedema or restriction of joint motion. Diagnosis of chronic radiation dermatitis is usually made by clinical examination. In case of unclear clinical manifestation, a biopsy and histopathological examination are recommended to exclude secondary malignancy. The most effective prophylaxis of chronic radiation dermatitis is the use of proper radiation therapy techniques to avoid unnecessary irradiation of healthy skin. Treatment of chronic radiation dermatitis is demanding. The majority of the interventions are based only on clinical practice. Telangiectasia may be treated with pulse dye laser therapy. Chronic postirradiation wounds need special dressings. In case of necrosis or severe ulceration, surgical intervention may be considered. Management of RIF should be complex. Available methods are rehabilitative care, pharmacotherapy, hyperbaric oxygen therapy, and laser therapy. Future challenges include the assessment of late skin toxicity in modern irradiation techniques. Special attention should be paid on genomics and

  15. 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

  16. 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

  17. 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

  18. 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

  19. Hematopoietic cell crisis

    International Nuclear Information System (INIS)

    Seed, T.M.

    1991-01-01

    Under select radiological conditions, chronic radiation exposure elicits a high incidence of myeloproliferative disease, principally myeloid leukemia (ML), in beagles. Previously we demonstrated that for full ML expression, a four-stage preclinical sequence is required, namely (I) suppression, (II) recovery, (III) accommodation, and (IV) preleukemic transition. Within this pathological sequence, a critical early event has been identified as the acquisition of radioresistence by hematopoietic pregenitors that serves to mediate a newfound regenerative hematopoietic capacity. As such, this event 'sets the stage' for preleukemic progression by initiating progression from preclinical phase I to II. Due to the nature of target cell suppression, the induction of crisis, and the outgrowth of progenitors with altered phenotypes, this preleukemic event resembles the 'immortalization' step of the in vitro transformation sequence following induction with either physical and chemical carcinogens. The radiological, temporal, and biological dictages governing this event have been extensively evaluated and will be discussed in light of their role in the induction and progression of chronic radiation leukemia. (author)

  20. Todralazine protects zebra fish from lethal doses of ionizing radiation: role of hematopoietic stem cell expansion

    International Nuclear Information System (INIS)

    Dimri, Manali; Joshi, Jaidev; Indracanti, Prem Kumar

    2013-01-01

    Radiation induced cell killing and hematopoietic stem cell depletion leads to compromised immune functions and opportunistic infections which significantly affect the recovery and survival upon irradiation. Any agent which can expand residual hematopoietic stem cells in irradiated organism can render protection from the effects of lethal doses of ionizing radiation. Johns Hopkins Clinical compound library (JHCCL) was screened for protection against lethal doses of ionizing radiation using developing zebra fish as a model organism. Modulation of radiation induced reactive oxygen species by the small molecules were done by DCFDA staining and for visual identification and quantification of apoptosis acridine orange assay, flow cytometry were employed respectively. Hematopoietic stem cell expansion potential was assessed by quantifying runx1 expression, a marker for definitive stem cells, were done by RT-PCR and by the kinetics of recovery from chemically induced anaemia. Todralazine hydrochloride from JHCCL exhibited promising results with potential anti radiation effects. A dose of 5μM was found to be the most effective and has rendered significant organ and whole body protection (100% survival advantage over a period of 6 days) against 20 Gy. However todralazine did not modulated radiation induced free radicals (monitored within 2 h of irradiation) and apoptosis in zebra fish embryos analysed at 8 and 24h post irradiation. Flow cytometric quantification of pre G1 population suggested the same. Chemoinformatics approaches were further carried out to elucidate possible targets which are contributing to its radioprotection potential. Structural similarity search suggested several targets and possible hematopoietic stem cell expanding potential. Treatment of zebra fish embryos with todralazine has lead to significant proliferation of hematopoietic stem cell as indicated by increase in expression of runx1. HSC expanding potential of todralazine was further supported by

  1. Radioprotective activity of Mentha piperita (Linn) against radiation induced alterations in peripheral blood of Swiss albino mice

    International Nuclear Information System (INIS)

    Samarth, R.M.; Goyal, P.K.; Ashok Kumar

    2001-01-01

    The radioprotective role of aqueous extract of Mentha piperita (Linn.) (RUBL 19443) against radiation induced hematological alterations in peripheral blood of Swiss albino mice was studied at various post-irradiation intervals between 6 hrs to 30 days. Oral administration of Mentha extract (ME) (1 gm/kg body weight) prior to whole-body irradiation showed a significant protection in terms of survival percentage and hematological parameters. Mice exposed to radiation (10 Gy) without ME pre-treatment exhibited signs of radiation sickness like anorexia, lethargicity, ruffled hairs and diarrhoea and such animals died within 10 days post-irradiation. Conversely, animals pre-treated with ME showed 58 percent survival until 30 days after exposure. A significant decline in hematological constituents was evident until day 5, at later period of observation (day 5 onwards), no animals could survive from control group whereas, in ME pre-treated irradiated group, a gradual recovery was noted in the hematological values. However, these hematological values remained significantly below the normal even till day 30. The results from the present study suggest that Mentha piperita (Linn.) has radioprotective role in stimulating/protecting the hematopoietic system thereby enhancing the survival and increasing the hematological constituents in peripheral blood of mice against lethal dose of gamma radiation. (author)

  2. Diagnosis and treatment of radiation-induced burns

    International Nuclear Information System (INIS)

    Portas, Mercedes; Pomerane, Armando; Genovese, Jorge; Perez, Maria R.; Gisone, Pablo

    2002-01-01

    The utilization of radioactive sources in medicine, industry and research is associated with a probability of accidental overexposures to ionizing radiation, among which localized irradiation are the most frequent events. Moreover, between 5 and 8 % of the patients undergoing therapeutical irradiations could exhibit a higher individual radiosensitivity which could account for severe skin reactions. Localized overexposures may damage not only epidermis and dermis but also deeper connective tissue, vessels, muscles and even bones. Within the framework of a cooperation agreement between the Buenos Aires Burn Hospital and the National Board of Nuclear Regulation, a Radio pathology Committee has been established in 1997 with the purpose of carrying out a collaborative project concerning diagnosis and treatment of radiological burns. The present document particularly considers radiological burns form the point of view of their physiopathology, physical and biological dosimetry, diagnosis prognosis and treatment. It also includes basic concepts of radiation biology and radio pathology. It could be an useful tool for training medical practitioners and also a practical guidance for organizing medical response in accidental overexposures. (author)

  3. Fatal accidental hypothermia and alcohol.

    Science.gov (United States)

    Albiin, N; Eriksson, A

    1984-01-01

    A series of 51 fatal cases of accidental hypothermia in northern Sweden has been reviewed. The cases conform well to previous investigations with respect to the mean age of the victims (48 years) and a predominance of males. The cases occurred mainly during the winter months and on Saturdays. Most cases succumbed at temperatures below -10 degrees C. The most frequent necropsy findings were areas of frostbite with purple discoloration of the skin, reddish lividity and superficial erosions of the gastric mucosa. Paradoxical undressing was present in more than half of the cases. About two thirds of the cases were under the influence of alcohol with a mean blood alcohol concentration of 1.6 g/l. Furthermore, at least half of the cases could be considered habitual drunkards. In conclusion, the present series shows two main groups of fatal hypothermia victims: one group of elderly persons, mostly chronic abusers and under the influence of alcohol (approximately two-thirds of the series), and another of younger and sober persons, performing recognised sporting activities (approximately one-fourth of the series).

  4. Accidental hypothermia in the sunbelt.

    Science.gov (United States)

    Thomas, D R

    1988-01-01

    Hypothermia in colder climates in the United States occurs predominately as a result of exposure of alcoholics to cold outdoor temperatures. Among 24 cases of accidental hypothermia occurring at a university medical center in the deep South, differences in clinical presentation were identified. In contrast to experience in colder climates, 17/22 cases (76%) developed at home. Alcohol was a factor in only 8/24 (33%). The elderly were at greatest risk, accounting for 16/24 patients (65%). Factors suggested to account for the high incidence of hypothermia in the elderly include abnormal temperature perception or regulation, intercurrent illness, social isolation, inadequate housing, and poverty. Coexisting medical conditions were identified as a potential cause of hypothermia in only 10/24 of these patients (42%). Social isolation was not a strong predictor, with 6/17 of the elderly (35%) living alone. Death occurred in 9/24 patients (37%), but survival could not be predicted from admission temperature, hypotension, anemia, or serum glucose. Since extreme cold temperatures are infrequent in the deep South, identified differences in demographics may be due to inadequate housing or lack of preparation for cold weather dangers.

  5. Accidental methanol ingestion: Case report

    Directory of Open Access Journals (Sweden)

    Bakker Jan

    2010-02-01

    Full Text Available Abstract Background The incidence of methanol (CH3OH intoxication differs enormously from country to country. Methanol intoxication is extremely rare in the Dutch population. Even a low dose can already be potentially lethal. Patients are conventionally treated with hemodialysis. Therefore we'd like to present a report of a foreign sailor in Rotterdam who accidentally caused himself severe methanol intoxication, with a maximum measured concentration of 4.4 g/L. Case presentation The patient presented with hemodynamic instability and severe metabolic acidosis with pH 6.69. The anion gap was 39 mmol/L and the osmol gap 73 mosmol/kg. Treatment with ethanol and continuous venovenous hemodiafiltration (CVVH-DF was initiated. Despite the hemodynamic instability it is was possible to achieve rapid correction of pH and methanol concentration with CVVH-DF while maintaining a stable and therapeutic ethanol serum concentration. Despite hemodynamic and acid-base improvement, our patient developed massive cerebral edema leading to brain death. Permission for organ donation was unfortunately not ascertained. Conclusions We conclude that in a hemodynamic instable situation high methanol concentrations and methanol-induced derangements of homeostasis are safely and effectively treated with CVVH-DF and that severe cerebral edema is another possible cause of death rather than the classical bleeding in the putamen area.

  6. Influence of radiation induced defect clusters on silicon particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Junkes, Alexandra

    2011-10-15

    The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) addresses some of today's most fundamental questions of particle physics, like the existence of the Higgs boson and supersymmetry. Two large general-purpose experiments (ATLAS, CMS) are installed to detect the products of high energy protonproton and nucleon-nucleon collisions. Silicon detectors are largely employed in the innermost region, the tracking area of the experiments. The proven technology and large scale availability make them the favorite choice. Within the framework of the LHC upgrade to the high-luminosity LHC, the luminosity will be increased to L=10{sup 35} cm{sup -2}s{sup -1}. In particular the pixel sensors in the innermost layers of the silicon trackers will be exposed to an extremely intense radiation field of mainly hadronic particles with fluences of up to {phi}{sub eq}=10{sup 16} cm{sup -2}. The radiation induced bulk damage in silicon sensors will lead to a severe degradation of the performance during their operational time. This work focusses on the improvement of the radiation tolerance of silicon materials (Float Zone, Magnetic Czochralski, epitaxial silicon) based on the evaluation of radiation induced defects in the silicon lattice using the Deep Level Transient Spectroscopy and the Thermally Stimulated Current methods. It reveals the outstanding role of extended defects (clusters) on the degradation of sensor properties after hadron irradiation in contrast to previous works that treated effects as caused by point defects. It has been found that two cluster related defects are responsible for the main generation of leakage current, the E5 defects with a level in the band gap at E{sub C}-0.460 eV and E205a at E{sub C}-0.395 eV where E{sub C} is the energy of the edge of the conduction band. The E5 defect can be assigned to the tri-vacancy (V{sub 3}) defect. Furthermore, isochronal annealing experiments have shown that the V{sub 3} defect

  7. Influence of radiation induced defect clusters on silicon particle detectors

    International Nuclear Information System (INIS)

    Junkes, Alexandra

    2011-10-01

    The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) addresses some of today's most fundamental questions of particle physics, like the existence of the Higgs boson and supersymmetry. Two large general-purpose experiments (ATLAS, CMS) are installed to detect the products of high energy protonproton and nucleon-nucleon collisions. Silicon detectors are largely employed in the innermost region, the tracking area of the experiments. The proven technology and large scale availability make them the favorite choice. Within the framework of the LHC upgrade to the high-luminosity LHC, the luminosity will be increased to L=10 35 cm -2 s -1 . In particular the pixel sensors in the innermost layers of the silicon trackers will be exposed to an extremely intense radiation field of mainly hadronic particles with fluences of up to Φ eq =10 16 cm -2 . The radiation induced bulk damage in silicon sensors will lead to a severe degradation of the performance during their operational time. This work focusses on the improvement of the radiation tolerance of silicon materials (Float Zone, Magnetic Czochralski, epitaxial silicon) based on the evaluation of radiation induced defects in the silicon lattice using the Deep Level Transient Spectroscopy and the Thermally Stimulated Current methods. It reveals the outstanding role of extended defects (clusters) on the degradation of sensor properties after hadron irradiation in contrast to previous works that treated effects as caused by point defects. It has been found that two cluster related defects are responsible for the main generation of leakage current, the E5 defects with a level in the band gap at E C -0.460 eV and E205a at E C -0.395 eV where E C is the energy of the edge of the conduction band. The E5 defect can be assigned to the tri-vacancy (V 3 ) defect. Furthermore, isochronal annealing experiments have shown that the V 3 defect exhibits a bistability, as does the leakage current. In oxygen

  8. Reconstruction of hematopoietic inductive microenvironment after transplantation of VCAM-1-modified human umbilical cord blood stromal cells.

    Directory of Open Access Journals (Sweden)

    Yao Liu

    Full Text Available The hematopoietic inductive microenvironment (HIM is where hematopoietic stem/progenitor cells grow and develop. Hematopoietic stromal cells were the key components of the HIM. In our previous study, we had successfully cultured and isolated human cord blood-derived stromal cells (HUCBSCs and demonstrated that they could secret hemopoietic growth factors such as GM-CSF, TPO, and SCF. However, it is still controversial whether HUCBSCs can be used for reconstruction of HIM. In this study, we first established a co-culture system of HUCBSCs and cord blood CD34(+ cells and then determined that using HUCBSCs as the adherent layer had significantly more newly formed colonies of each hematopoietic lineage than the control group, indicating that HUCBSCs had the ability to promote the proliferation of hematopoietic stem cells/progenitor cells. Furthermore, the number of colonies was significantly higher in vascular cell adhesion molecule-1 (VCAM-1-modified HUCBSCs, suggesting that the ability of HUCBSCs in promoting the proliferation of hematopoietic stem cells/progenitor cells was further enhanced after having been modified with VCAM-1. Next, HUCBSCs were infused into a radiation-damaged animal model, in which the recovery of hematopoiesis was observed. The results demonstrate that the transplanted HUCBSCs were "homed in" to bone marrow and played roles in promoting the recovery of irradiation-induced hematopoietic damage and repairing HIM. Compared with the control group, the HUCBSC group had significantly superior effectiveness in terms of the recovery time for hemogram and myelogram, CFU-F, CFU-GM, BFU-E, and CFU-Meg. Such differences were even more significant in VCAM-1-modified HUCBSCs group. We suggest that HUCBSCs are able to restore the functions of HIM and promote the recovery of radiation-induced hematopoietic damage. VCAM-1 plays an important role in supporting the repair of HIM damage.

  9. Hematopoietic stem cells and the aging hematopoietic system.

    Science.gov (United States)

    Gazit, Roi; Weissman, Irving L; Rossi, Derrick J

    2008-10-01

    The etiology of the age-associated pathophysiological changes of the hematopoietic system including the onset of anemia, diminished adaptive immune competence, and myelogenous disease development are underwritten by the loss of normal homeostatic control. As tissue and organ homeostasis in adults is primarily mediated by the activity of stem and progenitor cells, it has been suggested that the imbalances accompanying aging of the hematopoietic system may stem from alterations in the prevalence and/or functional capacity of hematopoietic stem cells (HSCs) and progenitors. In this review, we examine evidence implicating a role for stem cells in the aging of the hematopoietic system, and focus on the mechanisms suggested to contribute to stem cell aging.

  10. Radiation-induced bystander effects in cultured human stem cells.

    Directory of Open Access Journals (Sweden)

    Mykyta V Sokolov

    2010-12-01

    Full Text Available The radiation-induced "bystander effect" (RIBE was shown to occur in a number of experimental systems both in vitro and in vivo as a result of exposure to ionizing radiation (IR. RIBE manifests itself by intercellular communication from irradiated cells to non-irradiated cells which may cause DNA damage and eventual death in these bystander cells. It is known that human stem cells (hSC are ultimately involved in numerous crucial biological processes such as embryologic development; maintenance of normal homeostasis; aging; and aging-related pathologies such as cancerogenesis and other diseases. However, very little is known about radiation-induced bystander effect in hSC. To mechanistically interrogate RIBE responses and to gain novel insights into RIBE specifically in hSC compartment, both medium transfer and cell co-culture bystander protocols were employed.Human bone-marrow mesenchymal stem cells (hMSC and embryonic stem cells (hESC were irradiated with doses 0.2 Gy, 2 Gy and 10 Gy of X-rays, allowed to recover either for 1 hr or 24 hr. Then conditioned medium was collected and transferred to non-irradiated hSC for time course studies. In addition, irradiated hMSC were labeled with a vital CMRA dye and co-cultured with non-irradiated bystander hMSC. The medium transfer data showed no evidence for RIBE either in hMSC and hESC by the criteria of induction of DNA damage and for apoptotic cell death compared to non-irradiated cells (p>0.05. A lack of robust RIBE was also demonstrated in hMSC co-cultured with irradiated cells (p>0.05.These data indicate that hSC might not be susceptible to damaging effects of RIBE signaling compared to differentiated adult human somatic cells as shown previously. This finding could have profound implications in a field of radiation biology/oncology, in evaluating radiation risk of IR exposures, and for the safety and efficacy of hSC regenerative-based therapies.

  11. Scopolamine methylbromide mitigates radiation induced damage and lethality in zebrafish

    International Nuclear Information System (INIS)

    Shrivastava, Nitisha; Joshi, Jayadev; Ghosh, Subhajit; Dimri, Manali; Prem Kumar, Indracanti; Sehgal, Neeta

    2014-01-01

    In view of the strategic importance radiation countermeasures hold, the present study was undertaken to screen a collection of small molecule clinical compounds for possible radioprotective action using zebrafish as a model system. Preliminary screening in developing zebrafish embryos (24 hour post fertilization, (hpf)) using damage manifestations and survival as end point identified scopolamine methylbromide (SMB), a muscarinic receptor antagonist, as a potential radiomitigator. It was found to be optimal (60% survival advantage after 6 th post irradiation day) at a dose of 80 μM when added 3 h post 20 Gy exposure. Mechanistic studies suggested that SMB though exhibited no significant antioxidant potential, but was found to limit radiation induced apoptosis (pre G1 population) quantified through flow cytometry (6 and 5% reduction after 8 or 24 h after treatments) and annexin V staining (8% reduction). Further, quantitative analysis, using caspase 3 assay, revealed a 2.46 fold increase in apoptosis in irradiated group and treatment of irradiated zebrafish embryos with SMB led to a significant reduction in global apoptosis (1.7 fold; p<0.05) when compared to irradiated group. In silico studies based on structural and functional similarity with known radioprotectors suggested similarities with atropine, a known anti-inflammatory agent with muscarinic antagonism and radioprotective potential. In view of this SMB was tested, in silico, for possible anti-inflammatory action. Molecular docking studies revealed that SMB interacts (B.E-8.0 Kcal/mole) with cycloxygenase-2 (COX-2). In lieu of this, anti-inflammation activity was assessed through ChIN (chemically induced inflammation) method in 3 dpf (days post fertilization) embryos and SMB was found to significantly inhibit inflammation at all doses studied from 20-200 μM at 3 and 6 hpi (hours post inflammation). Overall the result suggests that scopolamine methylbromide mitigates radiation induced injury and lethality in

  12. Phase III evaluation of sucralfate for radiation-induced esophagitis

    International Nuclear Information System (INIS)

    McGinnis, W.L.; Loprinzi, C.L.; Buskirk, S.J.; Sloan, J.A.; Novotny, P.J.; Drummond, R.G.; Frank, A.R.; Shanahan, T.G.

    1996-01-01

    Purpose/Objective: To evaluate whether an oral sucralfate solution could prevent or alleviate symptoms of radiation-induced esophagitis in patients receiving thoracic radiation therapy. Materials and Methods: Patients considered for this trial must have been adults scheduled to receive thoracic radiation therapy to include the mediastinum to a dose of ≥ 5,000 cGy using 150 to 200 cGy per fraction or ≥ 4,000 cGy using ≥ 300 cGy per fraction. Contraindications to study participation included a known intolerance to sucralfate; previous radiation to the chest; planned use of sucralfate off study; pregnant or nursing women; cancers involving the mucosa of the esophagus; and/or an inability to take oral medications. Patients were stratified by their radiation therapy treatment plan, their age and their sex. Following stratification, they were randomized in a double blind manner to receive a sucralfate solution or an identical-appearing placebo solution. Esophagitis was measured by the treating physician, using the RTOG esophagitis toxicity grading criteria, at weekly intervals during the course of radiation therapy. In addition, patients completed short questionnaires weekly during the course of radiation therapy and for four weeks following completion of their radiation treatment program. Results: One hundred and two patients were randomized onto this study between August of 1993 and July of 1994. One patient was ineligible and four patients were cancelled prior to starting any study medication, leaving 97 total evaluable patients. All of the stratification factors were well balanced but there was a slightly higher incidence of current tobacco use in the placebo group. There was a differential drop out rate between the two arms. During the first two treatment weeks, only two of the placebo patients (4%) compared to 20 of the sucralfate patients (40%) dropped out of the study. After the second week, relatively equal drop out rates were seen with 9 sucralfate

  13. Radiation-induced bystander effects in vivo are sex specific

    International Nuclear Information System (INIS)

    Koturbash, Igor; Kutanzi, Kristy; Hendrickson, Karl; Rodriguez-Juarez, Rocio; Kogosov, Dmitry; Kovalchuk, Olga

    2008-01-01

    Ionizing radiation (IR) effects span beyond the area of direct exposure and can be observed in neighboring and distant naive cells and organs. This phenomenon is termed a 'bystander effect'. IR effects in directly exposed tissue in vivo are epigenetically mediated and distinct in males and females. Yet, IR-induced bystander effects have never been explored in a sex-specificity domain. We used an in vivo mouse model, whereby the bystander effects are studied in spleen of male and female animals subjected to head exposure when the rest of the body is protected by a medical-grade lead shield. We analyzed the induction of DNA damage and alterations in global DNA methylation. Molecular parameters were correlated with cellular proliferation and apoptosis levels. The changes observed in bystander organs are compared to the changes in unexposed animals and animals exposed to predicted and measured scatter doses. We have found the selective induction of DNA damage levels, global DNA methylation, cell proliferation and apoptosis in exposed and bystander spleen tissue of male and female mice. Sex differences were significantly diminished in animals subjected to a surgical removal of gonads. These data constitute the first evidence of sex differences in radiation-induced bystander effects in mouse spleen in vivo. We show the role of sex hormones in spleen bystander responses and discuss implications of the observed changes

  14. Toxic clinical hypoxic radiation sensitizers plus radiation-induced toxicity

    International Nuclear Information System (INIS)

    Richmond, R.C.

    1984-01-01

    The operational definition espoused twelve years ago that clinical hypoxic radiation sensitizers should be nontoxic interferes with the recognition and research of useful radiation sensitizers. Eight years ago the toxic antitumor drug cis-dichlorodiammineplatinum(II) was reported to be a hypoxic radiation sensitizer and the selective antitumor action of this drug was stressed as potentially creating tumor-targeted radiation sensitization. This rationale of oxidative antitumor drugs as toxic and targeted clinical sensitizers is useful, and has led to the study reported here. The antitumor drug cis-(1,1-cyclobutane-dicarboxylato)diammineplatinum(II), or JM-8, is being tested in clinical trials. Cells of S. typhimurium in PBS in the presence of 0.2mM JM-8 are found to be sensitized to irradiation under hypoxic, but not oxic, conditions. JM-8 is nontoxic to bacteria at this concentration, but upon irradiation the JM-8 solution becomes highly toxic. This radiation induced toxicity of JM-8 preferentially develops from hypoxic solution, and thus contributes to the rationale of hypoxic tumor cell destruction

  15. Alteration of radiation-induced hematotoxicity by amifostine

    International Nuclear Information System (INIS)

    Momm, Felix; Bechtold, Christine; Rudat, Volker; Strnad, Vratislav; Tsekos, Alexander; Fischer, Karin; Henke, Michael

    2001-01-01

    Purpose: To investigate whether amifostine can reduce radiation hematotoxicity. Patients and Methods: Seventy-three patients undergoing radiotherapy for squamous cell carcinoma of the head and neck at the university clinics of Freiburg, Heidelberg, and Erlangen were evaluated. All received 60 Gy (50-70 Gy) at 5x2 Gy fractions per week employing standard techniques. Thirty-five were randomized to receive 200 mg/m 2 amifostine i.v. 30 min before radiation; 38 served as control patients. Blood counts (total n=501) were determined before, during, and while completing radiotherapy. Changes of leukocyte, platelet, and hemoglobin levels were determined and compared using the t test. Results: The blood hemoglobin level and the platelet count were not affected by irradiation, for either the amifostine-treated or control patients. Similarly, the leukocyte counts of amifostine-treated patients did not change during irradiation. However, control patients experienced a decrease in leukocyte count from 8.1 x 10 3 /mm 3 to 5.8x10 3 /mm 3 (difference: 2.3x10 3 /mm 3 ). This seems to be line specific: Whereas amifostine does not affect lymphocyte count, a radiation-induced decrease of neutrophil granulocytes seems to be prevented. Conclusion: Amifostine protects from radiation hematotoxicity, particularly affecting the granulocytopoiesis. These data confirm results from our former study

  16. Hybrid model of the radiation-induced bystander effect

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Viviane V.B.; Faria, Fernando Pereira de; Grynberg, Suely Epsztein, E-mail: vitoriabraga06@gmail.com, E-mail: fernandopereirabh@gmail.com, E-mail: seg@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    The radiation-induced bystander effect (RIBE) refer to biological alterations in non-irradiated cells that occupy the same medium (culture or tissue) of irradiated cells. The biochemical mechanisms of the RIBE are not completely elucidated. However, several experiments indicate its existence. The objective of this work is to quantify the effect via stochastic and deterministic approaches. The hypotheses of the model are: a) one non-irradiated healthy cell interacts with signals that propagate through the medium. These signals are released by irradiated cells. At the time of interaction cell-signal, the cell can become damaged and signaling or damage and not signaling; b) Both types of damage cells repair with certain rate becoming health cells; c) The diffusion of signals obey the discrete diffusion equation with decay in two dimensions. d) The signal concentration released by irradiated cells depends on the dose in the low dose range (< 0.3 Gy) and saturates for higher dose values. As expected, the temporal analysis of the model as a function of the repair rate shows that the survival fraction decreases as the repair rate is reduced. The analysis of the extent of damage triggered by a signal concentration released by a single irradiated cell at time zero show that the damage grows with the maximum simulation time. The results show good agreement with the experimental data. The stochastic and deterministic methods used are in qualitative agreement, as expected. (author)

  17. Radiation-induced intestinal lesions. Prognosis and surgical management

    International Nuclear Information System (INIS)

    Van Haecke, P.; Vitaux, J.; Michot, F.; Hay, J.-M.; Flamant, Y.; Maillard, J.-N.

    1981-01-01

    Thirteen patients with intestinal lesions consecutive to radiotherapy for carcinoma of the uterus were operated upon between 1973 and 1979. The small bowel was involved in 9 patients and the colon and rectum in 4 patients. Urinary tract lesions were associated in 3 patients of each group. Intestinal necrosis, progression of the lesions and extensive pelvic fibrosis were the only criteria of poor prognosis. Twenty-two operations were performed: 4 for urinary tract lesions and 18 for intestinal lesions. Five patients died during the immediate post-operative period and five died within 2 to 30 months after surgery, including 4 whose carcinoma recurred. The operative technique should be selected according to the extent and severity of radiation-induced damage, as determined by pre-operative examination and thorough exploration of the abdominal cavity once opened. Limited lesions of the small bowel can be treated by resection, but intestinal bypass with latero-lateral anastomosis seems to be preferable in cases with extensive lesions. Patients with colorectal lesions should have defunctioning colostomy prior to any other procedure dictated by the state of affairs. Multiple anastomosis, extensive resections and excessive dissections should be avoided [fr

  18. Solvent influence during radiation induced grafting of styrene in PVDF

    International Nuclear Information System (INIS)

    Ferreira, Henrique P.; Parra, Duclerc F.; Lugao, Ademar B.

    2013-01-01

    Radiation-induced grafting was studied to produce styrene grafted poly(vinylidene fluoride) (PVDF) membranes. PVDF films with 0.125 mm thickness were irradiated at doses between 5 and 20 kGy in the presence of styrene/N,N-dimethylformamide (DMF), styrene/acetone or styrene/toluene solutions (1:1, v/v) at dose rate of 5 kGy h -1 by simultaneous method, using gamma rays from a Co-60, under nitrogen atmosphere and at room temperature. The films were characterized before and after modification by grafting yield (GY %), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM and EDS), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). GY results shows that grafting increases with dose and toluene hinders the grafting, leading to a small GY comparing to DMF and acetone. It was possible to confirm the grafting of styrene by FT-IR due to the new characteristics peaks and by the TG and DSC due to changes in thermal behavior of the grafted material. SEM and EDS show surface and cross-section distribution of the grafting, which takes place on the surface and heterogeneously with toluene as solvent and homogeneously and penetrating into the inner layers of the matrix using DMF and acetone as solvent. (author)

  19. Radiation induced degradation of dyes-An overview

    International Nuclear Information System (INIS)

    Rauf, M.A.; Ashraf, S. Salman

    2009-01-01

    Synthetic dyes are a major part of our life. Products ranging from clothes to leather accessories to furniture all depend on extensive use of organic dyes. An unfortunate side effect of extensive use of these chemicals is that huge amounts of these potentially carcinogenic compounds enter our water supplies. Various advanced oxidation processes (AOPs) including the use of high-energy radiation have been developed to degrade these compounds. In this review, dye decoloration and degradation as a result of its exposure to high energy radiation such as gamma radiation and pulsed electron beam are discussed in detail. The role of various transient species such as ·H, ·OH and e aq - are taken into account as reported by various researchers. Literature citations in this area show that e aq - is very effective in decolorization but is less active in the further degradation of the products formed. The degradation of the dyes is initiated exclusively by ·OH attack on electron-rich sites of the dye molecules. Additionally, various parameters that affect the efficiency of radiation induced degradation of dyes, such as effect of radiation dose, oxygen, pH, hydrogen peroxide, added ions and dye classes are also reviewed and summarized. Lastly, pilot plant application of radiation for wastewater treatment is briefly discussed.

  20. R and D activities on radiation induced mutation breeding

    International Nuclear Information System (INIS)

    Lapade, A.G.; Asencion, A.B.; Santos, I.S.; Grafia, A.O.; Veluz, AM.S.; Barrida, A.C.; Marbella, L.J.

    1996-01-01

    This paper summarizes the accomplishments, prospects and future plans of mutation breeding for crop improvement at the Philippine Nuclear Research Institute (PNRI). Mutation induction has become a proven way creating variation within a crop variety and inducing desired attributes that cannot be found in nature or have been lost during evolution. Several improved varieties with desirable traits were successfully developed through induced mutation breeding at our research institute. In rice, mutation breeding has resulted in the development of new varieties: (1) PARC 2, (2) Milagrosa mutant, (3) Bengawan mutant and (4) Azmil mutant. Mutation breeding in leguminous crops has led to the induction of an improved L 114 soybean mutant that is shorter that the original variety but yield about 40% more. Several PAEC mungbean varieties characterized with long pods that are non-shattering were also induced. In asexually propagated crops, an increase in yield and chlorophyll mutants were obtained in sweet potatos. Likewise, chlorophyll mutant which look-like 'ornamental bromeliads' and a mutant with reduced spines have been developed in pineapple Queen variety. At present, we have started a new project in mutation breeding in ornamentals. Tissue culture is being utilized in our mutation breeding program. In the near future, radiation induced mutagenesis coupled with in vitro culture techniques on protoplast culture and somatic hybridization will be integrated into our mutation breeding program to facilitate the production of new crop varieties. (author)

  1. Radiation-induced hypoxia may perpetuate late normal tissue injury

    International Nuclear Information System (INIS)

    Vujaskovic, Zeljko; Anscher, Mitchell S.; Feng, Q.-F.; Rabbani, Zahid N.; Amin, Khalid; Samulski, Thaddeus S.; Dewhirst, Mark W.; Haroon, Zishan A.

    2001-01-01

    Purpose: The purpose of this study was to determine whether or not hypoxia develops in rat lung tissue after radiation. Methods and Materials: Fisher-344 rats were irradiated to the right hemithorax using a single dose of 28 Gy. Pulmonary function was assessed by measuring the changes in respiratory rate every 2 weeks, for 6 months after irradiation. The hypoxia marker was administered 3 h before euthanasia. The tissues were harvested at 6 weeks and 6 months after irradiation and processed for immunohistochemistry. Results: A moderate hypoxia was detected in the rat lungs at 6 weeks after irradiation, before the onset of functional or histopathologic changes. The more severe hypoxia, that developed at the later time points (6 months) after irradiation, was associated with a significant increase in macrophage activity, collagen deposition, lung fibrosis, and elevation in the respiratory rate. Immunohistochemistry studies revealed an increase in TGF-β, VEGF, and CD-31 endothelial cell marker, suggesting a hypoxia-mediated activation of the profibrinogenic and proangiogenic pathways. Conclusion: A new paradigm of radiation-induced lung injury should consider postradiation hypoxia to be an important contributing factor mediating a continuous production of a number of inflammatory and fibrogenic cytokines

  2. Radiation induced degradation of dyes--an overview.

    Science.gov (United States)

    Rauf, M A; Ashraf, S Salman

    2009-07-15

    Synthetic dyes are a major part of our life. Products ranging from clothes to leather accessories to furniture all depend on extensive use of organic dyes. An unfortunate side effect of extensive use of these chemicals is that huge amounts of these potentially carcinogenic compounds enter our water supplies. Various advanced oxidation processes (AOPs) including the use of high-energy radiation have been developed to degrade these compounds. In this review, dye decoloration and degradation as a result of its exposure to high energy radiation such as gamma radiation and pulsed electron beam are discussed in detail. The role of various transient species such as H, OH and e(aq)(-) are taken into account as reported by various researchers. Literature citations in this area show that e(aq)(-) is very effective in decolorization but is less active in the further degradation of the products formed. The degradation of the dyes is initiated exclusively by OH attack on electron-rich sites of the dye molecules. Additionally, various parameters that affect the efficiency of radiation induced degradation of dyes, such as effect of radiation dose, oxygen, pH, hydrogen peroxide, added ions and dye classes are also reviewed and summarized. Lastly, pilot plant application of radiation for wastewater treatment is briefly discussed.

  3. Survey of case reports of radiation-induced cancer

    International Nuclear Information System (INIS)

    Yoshizawa, Y.; Kusama, T.

    1977-01-01

    A survey of the cases reported as radiation-induced cancer in chief organs (the breast, the uterus, the pharynx and larynx, the colon, and the bone) was carried out. The number of the cases which were found by this survey were 10 in the breast, 548 in the uterus, 130 in the pharyns and larynx, 80 in the colon, and 256 in the bone. The most of these cases had received radiation for the purpose of treatment of non-malignant disease. The average latent period were 15.0 years in the cases of breast cancer, 10.1 years in uterus cancer, 27.3 years in pahrynx and larynx cancer, 13.6 years in colon cancer, and 15.5 years in bone cancer. The lowest radiation dose were 1470 rads in the cases of breast cancer, 900 rads in uterus in colon cancer, 4000 rads in pahrynx and larynx cancer, 460 rads in colon cancer, and 2700 rads in bone cancer. Histopathological findings, sex difference, onset age, and others were investigated in each organ. This survey gave many valuable informations for radiation protection and safety

  4. Mechanism of Hydrophilicity by Radiation-Induced Surface Activation

    Science.gov (United States)

    Honjo, Yoshio; Furuya, Masahiro; Takamasa, Tomoji; Okamoto, Koji

    When a metal oxide is irradiated by gamma rays, the irradiated surface becomes hydrophilic. This surface phenomenon is called as radiation-induced surface activation (RISA) hydrophilicity. In order to investigate gamma ray-induced and photoinduced hydrophilicity, the contact angles of water droplets on a titanium dioxide surface were measured in terms of irradiation intensity and time for gamma rays of cobalt-60 and for ultraviolet rays. Reciprocals of the contact angles increased in proportion to the irradiation time before the contact angles reached its super-hydrophilic state. The irradiation time dependency is equal to each other qualitatively. In addition, an effect of ambient gas was investigated. In pure argon gas, the contact angle remains the same against the irradiation time. This clearly indicates that certain humidity is required in ambient gas to take place of RISA hydrophilicity. A single crystal titanium dioxide (100) surface was analyzed by X-ray photoelectron spectrometry (XPS). After irradiation with gamma rays, a peak was found in the O1s spectrum, which indicates the adsorption of dissociative water to a surface 5-fold coordinate titanium site, and the formation of a surface hydroxyl group. We conclude that the RISA hydrophilicity is caused by chemisorption of the hydroxyl group on the surface.

  5. Outcome of Carotid Artery Stenting for Radiation-Induced Stenosis

    International Nuclear Information System (INIS)

    Dorresteijn, Lucille; Vogels, Oscar; Leeuw, Frank-Erik de; Vos, Jan-Albert; Christiaans, Marleen H.; Ackerstaff, Rob; Kappelle, Arnoud C.

    2010-01-01

    Purpose: Patients who have been irradiated at the neck have an increased risk of symptomatic stenosis of the carotid artery during follow-up. Carotid angioplasty and stenting (CAS) can be a preferable alternative treatment to carotid endarterectomy, which is associated with increased operative risks in these patients. Methods and Materials: We performed a prospective cohort study of 24 previously irradiated patients who underwent CAS for symptomatic carotid stenosis. We assessed periprocedural and nonprocedural events including transient ischemic attack (TIA), nondisabling stroke, disabling stoke, and death. Patency rates were evaluated on duplex ultrasound scans. Restenosis was defined as a stenosis of >50% at the stent location. Results: Periprocedural TIA rate was 8%, and periprocedural stroke (nondisabling) occurred in 4% of patients. After a mean follow-up of 3.3 years (range, 0.3-11.0 years), only one ipsilateral incident event (TIA) had occurred (4%). In 12% of patients, a contralateral incident event was present: one TIA (4%) and two strokes (12%, two disabling strokes). Restenosis was apparent in 17%, 33%, and 42% at 3, 12, and 24 months, respectively, although none of the patients with restenosed vessels became symptomatic. The length of the irradiation to CAS interval proved the only significant risk factor for restenosis. Conclusions: The results of CAS for radiation-induced carotid stenosis are favorable in terms of recurrence of cerebrovascular events at the CAS site.

  6. Hybrid model of the radiation-induced bystander effect

    International Nuclear Information System (INIS)

    Braga, Viviane V.B.; Faria, Fernando Pereira de; Grynberg, Suely Epsztein

    2013-01-01

    The radiation-induced bystander effect (RIBE) refer to biological alterations in non-irradiated cells that occupy the same medium (culture or tissue) of irradiated cells. The biochemical mechanisms of the RIBE are not completely elucidated. However, several experiments indicate its existence. The objective of this work is to quantify the effect via stochastic and deterministic approaches. The hypotheses of the model are: a) one non-irradiated healthy cell interacts with signals that propagate through the medium. These signals are released by irradiated cells. At the time of interaction cell-signal, the cell can become damaged and signaling or damage and not signaling; b) Both types of damage cells repair with certain rate becoming health cells; c) The diffusion of signals obey the discrete diffusion equation with decay in two dimensions. d) The signal concentration released by irradiated cells depends on the dose in the low dose range (< 0.3 Gy) and saturates for higher dose values. As expected, the temporal analysis of the model as a function of the repair rate shows that the survival fraction decreases as the repair rate is reduced. The analysis of the extent of damage triggered by a signal concentration released by a single irradiated cell at time zero show that the damage grows with the maximum simulation time. The results show good agreement with the experimental data. The stochastic and deterministic methods used are in qualitative agreement, as expected. (author)

  7. Chromatin Structure and Radiation-Induced Intrachromosome Exchange

    Science.gov (United States)

    Mangala; Zhang, Ye; Hada, Megumi; Cucinotta, Francis A.; Wu, Honglu

    2011-01-01

    We have recently investigated the location of breaks involved in intrachromosomal type exchange events, using the multicolor banding in situ hybridization (mBAND) technique for human chromosome 3. In human epithelial cells exposed to both low- and high-LET radiations in vitro, intrachromosome exchanges were found to occur preferentially between a break in the 3p21 and one in the 3q11. Exchanges were also observed between a break in 3p21 and one in 3q26, but few exchanges were observed between breaks in 3q11 and 3q26, even though the two regions were on the same arm of the chromosome. To explore the relationships between intrachromosome exchanges and chromatin structure, we used probes that hybridize the three regions of 3p21, 3q11 and 3q26, and measured the distance between two of the three regions in interphase cells. We further analyzed fragile sites on the chromosome that have been identified in various types of cancers. Our results demonstrated that the distribution of breaks involved in radiation-induced intrachromosome aberrations depends upon both the location of fragile sites and the folding of chromatins

  8. Contribution to the study of radiation induced bone tissue cancer

    International Nuclear Information System (INIS)

    Bouet, Monique.

    1975-01-01

    In this work four original observations of more or less long-delayed cancers induced by ionizing radiations are compared with 34 other cases in the literature, after which an attempt is made to establish a general and prognostic synthesis of the results; the indications to emerge are as follows: - Ionizing radiation-induced cancers are very rare, especially when compared with the extensive therapeutic use made of X-rays; - The probability of radio-cancer formation, though no figures are given in the many papers consulted, seems nevertheless to be higher in cases of benign lesion irradiation; - Induced cancers have been observed after treatments with all types of radiation, whether or not the lesion is tumoral or cancerous, whatever the patient's age at the time of irradiations; - As a general rule these neoplasms appear after a variable latency period but usually from the 6th post-radiotherapy year onwards, with a greater frequency range between 6 and 12 years; - These induced cancers are generally epitheliomas or sarcomas, the latter being noticeably more predominant than in the case of spontaneous cancers. Leukoses may also be observed [fr

  9. Mechanisms of radiation-induced neoplastic cell transformation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table.

  10. Radiation-Induced Notch Signaling in Breast Cancer Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Lagadec, Chann [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Vlashi, Erina [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California (United States); Alhiyari, Yazeed; Phillips, Tiffany M.; Bochkur Dratver, Milana [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Pajonk, Frank, E-mail: fpajonk@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California (United States)

    2013-11-01

    Purpose: To explore patterns of Notch receptor and ligand expression in response to radiation that could be crucial in defining optimal dosing schemes for γ-secretase inhibitors if combined with radiation. Methods and Materials: Using MCF-7 and T47D breast cancer cell lines, we used real-time reverse transcription–polymerase chain reaction to study the Notch pathway in response to radiation. Results: We show that Notch receptor and ligand expression during the first 48 hours after irradiation followed a complex radiation dose–dependent pattern and was most pronounced in mammospheres, enriched for breast cancer stem cells. Additionally, radiation activated the Notch pathway. Treatment with a γ-secretase inhibitor prevented radiation-induced Notch family gene expression and led to a significant reduction in the size of the breast cancer stem cell pool. Conclusions: Our results indicate that, if combined with radiation, γ-secretase inhibitors may prevent up-regulation of Notch receptor and ligand family members and thus reduce the number of surviving breast cancer stem cells.

  11. Submandibular salivary gland transfer prevents radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Jha, Naresh; Seikaly, Hadi; McGaw, Timothy; Coulter, Linda

    2000-01-01

    Background: Xerostomia is a significant morbidity of radiation therapy in the management of head and neck cancers. We hypothesized that the surgical transfer of one submandibular salivary gland to submental space, outside the proposed radiation field, prior to starting radiation treatment, would prevent xerostomia. Methods: We are conducting a prospective clinical trial where the submandibular gland is transferred as part of the surgical intervention. The patients are followed clinically, with salivary flow studies and University of Washington quality of life questionnaire. Results: We report early results of 16 patients who have undergone this procedure. Seven patients have finished and 2 patients are currently undergoing radiation treatment. In 2 patients, no postoperative radiation treatment was indicated. Two patients are waiting to start radiation treatment and 2 patients refused treatment after surgery. The surgical transfer was abandoned in 1 patient. All of the transferred salivary glands were positioned outside the proposed radiation fields and were functional. The patients did not complain of any xerostomia and developed only minimal oral mucositis. There were no surgical complications. Conclusions: Surgical transfer of a submandibular salivary gland to the submental space (outside the radiation field) preserves its function and prevents the development of radiation-induced xerostomia

  12. Pilocarpine and carbacholine in treatment of radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Joensuu, H.; Bostroem, P.; Makkonen, T.

    1993-01-01

    Twenty-four patients with radiation-related xerostomia were treated with oral pilocarpine solution 6 mg t.i.d., and after a 4-week drug-free period 16 of these patients were treated with carbacholine 2 mg tablets t.i.d. Basal and stimulated whole saliva flow rates were measured before commencing the drug treatment, and after 1 and 12 weeks on treatment. On a subjective linear scale both pilocarpine (p=0.01) and carbacholine (p=0.02) improved mouth moistness. Only 2 of the 8 patients with no basal or stimulated saliva flow reported some subjective benefit from the drug treatment, whereas all 8 patients with less severe xerostomia improved (p=0.007). However, the salivary flow rates measured 12 h after the last drug dose did not improve with either drug. Both drugs were generally well tolerated. It is concluded that both drugs may be useful in the treatment of radiation-induced xerostomia among patients with residual salivary function. (author). 6 refs., tabs

  13. 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

  14. Radiation-induced tumours of the head and neck

    Energy Technology Data Exchange (ETDEWEB)

    Laan, B.F.A.M. van der; Baris, G.; Gregor, R.T.; Hilgers, F.J.M.; Balm, A.J.M. [Nederlands Kanker Inst. `Antoni van Leeuwenhoekhuis`, Amsterdam (Netherlands)

    1995-04-01

    In order to study the induction of malignancy in normal tissues due to ionizing radiation, we reviewed the files of 2500 patients with a tumour of the head and neck treated at the Netherlands Cancer Institute (Antoni van Leeuwenhoek Ziekenhuis), Amsterdam, from 1977 to 1993. We then checked whether or not these patients had been previously irradiated. Patients with a thyroid carcinoma or skin cancer were excluded from the study, since it is generally known that previous irradiation is a risk factor in these tumours. Eighteen patients were found to have a malignancy within a previous irradiated area (0.70 per cent). The mean interval between radiation and diagnosis of the head and neck tumour was 36.5 years. There were five soft tissue sarcomas, nine squamous cell carcinomas and four salivary gland tumours. Fourteen patients were operated upon whereas four received palliative treatment only. The median survival of the total group was 3.5 years. Particularly in young patients, because of the better cancer therapy and prolonged survival, one must be aware of the increased risk of radiation-induced tumours. (author).

  15. Radiation-induced embrittlement in light water reactor pressure vessels

    International Nuclear Information System (INIS)

    Gold, R.; McElroy, W.N.

    1987-01-01

    In operating light water reactor (LWR) commercial power plants, neutron radiation induces embrittlement of the pressure vessel (PV) and its support structures. As a consequence, LWR-PV integrity is a primary safety consideration. LWR-PV integry is a significant economic consideration because the PV and its support structures are nonreplaceable power plant components and embrittlement of these components can therefore limit the effective operating lifetime of the plant. In addition to plant life considerations, LWR-PV embrittlement creates significant cycle-to-cycle impact through the restriction of normal heat-up and cool-down reactor operations. Recent LWR-PV benchmark experiments are analyzed. On this bases, it is established that an exponential representation accurately describes the spatial dependence of neutron exposure in LWR-PV. Implications produced by simple exponental behavior are explained and trend-curve models for the predictions of PV embrittelment are derived. These derivations provide for a clearer understanding and assessment of the assumptions underlying these trend-curve models. It is demonstrated that LWR-PV embrittlement possesses significant material dependence. (orig.)

  16. Radiation-induced oxidative chemical changes in dehydrated egg products

    International Nuclear Information System (INIS)

    Katusin-Rasem, B.; Mihaljevic, B.; Razem, D.

    1992-01-01

    Radiation-induced buildup of lipid hydroperoxides (LOOH) and destruction of carotenoids were followed in whole egg powder and egg yolk powder as functions of dose, dose rate, and the presence of oxygen. In the absence of air the formation of LOOH was limited by the available oxygen, while destruction of carotenoids progressed linearly with dose; neither process depended on the dose rate. In the presence of air, the accumulation of LOOH and the destruction of carotenoids were strongly coupled and inversely proportional to the dose rate. The induction dose of 2.5 kGy was observed in air in both whole egg powder and egg yolk powder, independent of the dose rate. The practical consequence is that radiation decontamination can be carried out in the presence of air at the highest available dose rate by a dose not exceeding 2.5 kGy to avoid extensive degradation. This dose is adequate for a 10(3) reduction factor of Salmonella and well within the threshold dose of 3 kGy for organoleptic changes

  17. Radiation induced sarcoma after treatment of glioblastoma: case report

    International Nuclear Information System (INIS)

    Rosa, Victor Domingos Lisita; Anjos, Caroline Souza dos; Candido, Priscila Barile Marchi; Dias Junior, Antonio Soares; Santos, Evandro Airton Sordi dos; Godoy, Antonio Carlos Cavalcante; Saggioro, Fabiano P.; Carlotti Junior, Carlos Gilberto; Oliveira, Harley Francisco de; Peria, Fernanda Maris

    2016-01-01

    Introduction: Glioblastoma multiform is the most lethal central nervous system neoplasm, with a median survival of around 13 months and the worst prognosis among all gliomas. The therapeutic approach of glioblastoma consists in neurosurgery with maximum possible resection of tumor volume, followed by radiotherapy and chemotherapy. Radiotherapy reduces the risk of tumor recurrence through direct and indirect damage to tumor deoxyribonucleic acid. The long-term effects of radiation therapy include tissue necrosis, vasculopathy, and radiation-induced neoplasia. The most reported secondary intracranial malignant tumors include meningiomas, gliomas, and sarcomas. The latency period between skull radiotherapy and the appearance of radioinduced lesions varies in the literature from six months to 47 years, with an average of 18.7 years. Case report: The present report describes the appearance of high-grade spindle cell sarcoma after ten months in a patient who received glioblastoma treatment at Hospital das Clínicas of Ribeirão Preto of the University of São Paulo. Conclusion: The rarity of this association is probably due to the poor survival of patients with glioblastoma, thus limiting the time to development of secondary neoplasia

  18. Radiation induced destruction of thebaine, papaverine and noscapine in methanol

    International Nuclear Information System (INIS)

    Kantoğlu, Ömer; Ergun, Ece

    2016-01-01

    The presence of methanol decreases the efficiency of radiation-induced decomposition of alkaloids in wastewater. Intermediate products were observed before the complete degradation of irradiated alkaloids. In order to identify the structure of the by-products and the formation pathway, thebaine, papaverine and noscapine solutions were prepared in pure methanol and irradiated using a 60 Co gamma cell at absorbed doses of 0, 1, 3, 5, 7, 10, 30, 50 and 80 kGy. The dose-dependent alkaloid degradation and by-product formation were monitored by ESI mass spectrometer. Molecular structures of the by-products and reaction pathways were proposed. Oxygenated and methoxy group containing organic compounds was observed in the mass spectra of irradiated alkaloids. At initial dose values oxygenated by-products were formed due to the presence of dissolved oxygen in solutions. After the consumption of dissolved oxygen with radicals, the main mechanism was addition of solvent radicals to alkaloid structure. However, it was determined that alkaloids and by-products were completely degraded at doses higher than 50 kGy. The G-value and degradation efficiency of alkaloids were also evaluated. - Highlights: • Oxygenated and methoxy group containing by-products were observed in the mass spectra. • The addition of methanol radiolysis products to alkaloid structure was suggested. • Intermediate products were decomposed at doses above 50 kGy. • The destruction efficiency and degradation G-value of alkaloids were calculated.

  19. Radiation-induced modification of titanium nickelide with fast neutrons

    Science.gov (United States)

    Parkhomenko, V. D.; Dubinin, S. F.

    2012-07-01

    We present a review of the investigations of the effect of fast neutrons on the structure and properties of titanium nickelide that were performed by the authors on an IVV-2M atomic reactor (Zarechnyi). It has been established that at small fluences of fast neutrons atomic disordering of crystals is observed; as the fluence increases, the material becomes partially amorphized; and at fluences higher than 1 × 1020 cm-2, the material transforms completely into the amorphous state. It has been shown that the amorphous state produced by neutron irradiation differs substantially from the amorphous state of materials obtained by conventional methods. In particular, if a single-crystal specimen is subjected to "neutron" amorphization (most of the investigations were carried out using single crystals), after annealing of radiation-induced defects the single crystal is restored with the initial orientation and perfection. The structural studies were conducted by the methods of neutron and X-ray diffraction. Based on these studies, as well as on the results of small-angle neutron scattering and dilatometric and resistivity measurements, the "defect" state of irradiated materials has been examined in detail. The radiation resistance of titanium nickelide has been estimated.

  20. Radiation-induced crosslinking of syndiotactic 1,2-polybutadiene

    International Nuclear Information System (INIS)

    Iwai, Tadashi; Hoshino, Sadao; Yamamoto, Rokuro; Okamoto, Hidemasa; Obana, Kazuyoshi.

    1978-01-01

    Crystalline syndiotactic 1, 2-polybutadiene (hereafter abbreviated as 1, 2-PB) developed in Ube Industries, Ltd. by its own technology is a new thermoplastic resin belonging to the intermediate region between rubber and plastics in its flexibility. By selecting appropriate catalyst composition, 1, 2-PB having the melting point of 90 to 200 deg. C and crystallization of 10 to 65% can be obtained. These 1, 2-PBs can be worked to formed products by general thermoplastic forming methods such as injection molding, extrusion forming and blow forming. Radiation-crosslinked 1, 2-PB changed to very hard polymers through heat treatment. This change has been found to be radical chain reaction of cyclic polymerization. The relation of radiation-induced crosslinking and thermal expansion behavior, and the changes of appearance and structural and physical properties with heat treatment of these polymers are described. That is, specific gravity has increased, tensile strength has been enhanced, and elongation has decreased. While dielectric strength and arc resistivity have been upgraded. Therefore, these polymers can be used for the following applications: food wrapping film, molded notions, molded low foaming material for the soles of footwears, highly foaming moldings such as sponges, electric insulation material such as cable coating and adhesives for many materials. It is considered that crosslinking contributes to the application to electric insulation materials and heat curing to heat-resistant materials and parts. (Wakatsuki, Y.)

  1. Radiation-induced degradation of polysaccharide sodium alginate

    International Nuclear Information System (INIS)

    Yang Jiaxia; Li Xiaoyan

    2013-01-01

    The radiation-induced degradation of sodium alginate by 60 Co γ-rays was investigated in air at ambient temperature, and the change in their molecular weights was measured by multi-angle laser light scattering detector equipped with gel permeation chromatography (MALLS/GPC). The molecular weight of sodium alginate decreases with the increase of absorbed dose in the range of 0-60 kGy at the dose rate of 80 Gy/ min. The dispersion of molecular weight distribution of sodium alginate becomes narrow along with the absorbed dose. The weight-average molecular weight (M w ) changes from 321596.5 to 10024 when the absorbed dose increases from o kGy to 60 kGy. It is found that the degraded sodium alginate with molecular weight peak of 6000 is 83.22% of cumulative weight fraction. Anyway, the sodium alginate may have comprehensive application in the fields of agriculture, medicine and cosmetology as it can be absorbed well by biological tissue, if its weight-average molecular weight is below 10000. It is also found that new components will be contained in the products of sodium alginate degraded by irradiation. The further study dealing with the checking the biological safety and purification shall be performed. (authors)

  2. Radiation-induced polymerization of some vinyl compounds

    International Nuclear Information System (INIS)

    Panta, P.; Gluszewski, W.; Zimek, Z.; Wojtynska, E.K.

    1998-01-01

    Complete text of publication follows. The action of accelerator electron beams (E.B.) and Co-60 gamma rays in inducing polymerization of monomers and oligomers of 2-ethylhexyl acrylate, acrylic acid and vinyl acetate was investigated. Using 10 MeV and 10 kW E.B. the time of free radical polymerization as short as several seconds was evaluated. The second order kinetics of polymerization reactions is proposed. Life times of free radicals generated during irradiation of 2-ethylhexyl acrylate, acrylic acid and vinyl acetate are very short at room temperature. For ESR measurements suitable samples were irradiated at 77 K and measured during defrosting. According to available literature data and own results the radiation-induced polymerization of above mentioned vinyl compounds is stopped during EB irradiation, without post effect. Besides polymerization of individual compounds we observe also mutual co-polymerization of appropriate mixtures of 2-ethylhexyl acrylate with acrylic acid and also vinyl acetate. Product of such co-polymerization exhibit some adhesive properties

  3. Sucralfate for the treatment of radiation induced mucositis

    International Nuclear Information System (INIS)

    Belka, C.; Hoffmann, W.; Paulsen, F.; Bamberg, M.

    1997-01-01

    Purpose: Radiotherapy, a cornerstone in the management of head and neck cancer, pelvic cancer, and esophageal cancer is associated with a marked mucosal toxicity. Pain, malnutrition and diarrhea are the most prevalent clinical symptoms of radiation induced mucosal damage. Because there is no known way to obviate radiation mucositis all efforts to prevent aggravation and accelerate healing of mucosal changes are of great importance. Numerous agents including antimicrobials, local and systemic analgesics, antiinflammatory drugs, antidiarrheal drugs, in combination with intensive dietetic care are used to relieve symptoms. Recently coating agents like the polyaluminum-sucrose complex sucralfate were suggested for the prevention and treatment of mucosal reactions. Since sucralfate protects ulcerated epithelium by coating, liberates protective prostaglandins and increases the local availability of protective factors this drug might directly interact with the pathogenesis of mucositis. Patients and Method: The results of available studies are analysed and discussed. Results: The results of several studies indicate that sucralfate treatment especially during radiotherapy for pelvic cancer leads to a significant amelioration of clinical symptoms and morphological changes. An application of sucralfate during radiotherapy of head and neck cancer reveals only limited benefits in most studies performed. Conclusion: Nevertheless sucralfate is a save, cheap and active drug for the prevention and treatment of radiation mucositis especially in patients with pelvic irradiation. (orig.) [de

  4. Radiation-induced aneusomic clones in bone marrow of rats

    International Nuclear Information System (INIS)

    Kohno, Sei-Ichi; Ishihara, Takaaki

    1976-01-01

    Wistar rats 3 months old were given a single whole-body X-irradiation with 700 R. They were killed 9.3 months, on average, after irradiation. From the bone marrows of the 23 irradiated rats, 54 clones of cells with radiation-induced chromosome abnormalities ranging from 3.3 to 78.3% in size were obtained. Karyotype analysis at the banding level showed that 43 out of the 54 clones had balanced chromosome constitutions and that the remaining 11 clones were unbalanced. The 43 balanced clones consisted of 33 clones with reciprocal translocations, 6 with inversions and 4 with both translocations and inversions. The 11 unbalanced clones were made up of 7 aneuploid clones and 4 pseudo-diploid clones. Of the 54 clones, 15 were large with frequencies of more than 25%. Contrary to general belief that cells with unbalanced chromosome constitutions have less capacity to proliferate than those with balanced ones, 8 of the 15 large clones, especially all, except 1, of the largest 6 clones were unbalanced, either aneuploid or pseudo-diploid

  5. Perinatal radiation-induced renal damage in the beagle

    International Nuclear Information System (INIS)

    Jaenke, R.S.; Angleton, G.M.

    1990-01-01

    The developing perinatal kidney is particularly sensitive to radiation. The pathogenesis of the radiation-induced lesion is related to the destruction of outer cortical developing nephrons and direct radiation injury with secondary hemodynamic alterations in remnant nephrons. In this study, which is part of a life span investigation of the effects of whole-body gamma radiation during prenatal and early postnatal life, dogs were given 0, 0.16, 0.83, or 1.25 Gy irradiation at either 55 days postcoitus or 2 days postpartum and were examined morphometrically and histopathologically at 70 days of age. Although irradiated dogs showed no reduction in the total number of nephrons per kidney, there was a significant increase in the total number and relative percentage of immature, dysplastic glomeruli. In addition, deeper cortical glomeruli of irradiated kidneys exhibited mesangial sclerosis similar to that associated with progressive renal failure in our previous studies. These findings are in accord with those reported at doses of 2.24 to 3.57 Gy and demonstrate that the perinatal kidney is affected by radiation doses much lower than previously demonstrated

  6. Modification of synthetic fibers by radiation-induced grafting

    International Nuclear Information System (INIS)

    Kaji, Kanako

    1981-05-01

    The present report describes studies to modify properties of synthetic fibers by radiation-induced grafting technique. This technique was employed since it is considered to be generally applicable to the grafting of a radically polymerizable monomer onto fiber. Three synthetic fibers were used mainly in the present studies; (1) polyester fiber which is ranked as the first in the amount of production in the synthetic fibers at present and is expected to increase in its importance in the future, (2) poly (vinyl chloride) fiber which is inexpensive and fire-retardant, and (3) polyethylene fiber which is not yet used in apparel at present. In order to perform the grafting, the following two methods were studied; one is to graft monomer uniformly in the fiber preventing homopolymerization of the monomer outside of the fiber, and the other to graft monomer only on the fiber surface. Using these methods, the following experiments were carried out and fairly good results as expected were obtained. (1) In the case of polyester fiber it was intended to make this more hydrophilic and fire-retardant. (2) Concerning to poly(vinyl chloride) fiber experiments were carried out to make the fiber more hydrophilic and simultaneously more heat-resistant. (3) In the case of polyethylene fiber, target was fire-retardance and heat-resistance. (author)

  7. Alloantigenic phenotype of radiation-induced thymomas in the mouse

    International Nuclear Information System (INIS)

    Hogarth, P.M.; Henning, M.M.; McKenzie, I.F.C.

    1982-01-01

    The alloantigenic phenotype of 21 radiation-induced thymomas is described. Monoclonal antibodies and conventional antisera, absorbed to remove contaminating antibodies, were used to test the thymomas directly for the presence of H-2, Ia, Ly-1, Ly-2, Ly-4, Ly-5, Ly-6, Ly-9, Ly-15, Thy-1, TL, and Qa-2 antigens, and for surface immunoglobulin. The phenotypes obtained by direct tests were also confirmed by absorption studies. The tumors were all of T-cell origin (Thy-1 + Ig - ) and showed a restricted heterogeneity of their cell surface phenotype, concordant with the known alloantigenic phenotypes of functional T-cells. Thus the thymomas could be classified into 7 groups based on the differing expressions of Ia, Ly-1, Ly-2, Ly-4, and Ly-6 specificities; all tumors were H-2 + , Ly-5 + , Ly-9 + , and Ly-15 + . Thus a wide variety of phenotypically diverse tumors could be detected; if these represent the clonal expansion of different functional subsets, they could provide a valuable set of functional T-cells

  8. Radiation-induced hypopituitarism is dose-dependent

    International Nuclear Information System (INIS)

    Littley, M.D.; Shalet, S.M.; Beardwell, C.G.; Robinson, E.L.; Sutton, M.L.

    1989-01-01

    Radiation-induced hypopituitarism has been studies prospectively for up to 12 years in 251 adult patients treated for pituitary disease with external radiotherapy, ranging in dose from 20 Gy in eight fractions over 11 days to 45 Gy in 15 fractions over 21 days. Ten further patients were studied 2-4 years after whole-body irradiation for haematological malignancies using 12 Gy in six fractions over 3 days and seven patients were studied 3-11 years after whole-brain radiotherapy for a primary brain tumour (30 Gy, eight fractions, 11 days). Five years after treatment, patients who received 20 Gy had an incidence of TSH deficiency of 9% and in patients treated with 35-37 Gy, 40 Gy and 42-45 Gy, the incidence of TSH deficiency increased significantly with increasing dose. A similar relationship was observed for both ACTH and gonadotrophin deficiencies when the 20 Gy group was compared to patients treated with 35-45 Gy. Growth hormone deficiency was universal by 5 years over the dose range 35-45 Gy. In seven patients who were treated with 30 Gy in eight fractions over 11 days, deficiencies were observed at a similar frequency to the 40 Gy group (15 fractions, 21 days). No evidence of pituitary dysfunction was detected in the ten patients who received 12 Gy (six fractions, 3 days). (author)

  9. Mechanisms of radiation-induced neoplastic cell transformation

    International Nuclear Information System (INIS)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table

  10. Radiation induced oxidative damage modification by cholesterol in liposomal membrane

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, B.N. [Radiation Biology and Biochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Mishra, K.P. [Radiation Biology and Biochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    1999-05-01

    Ionizing radiation induced structural and chemical alterations in egg lecithin liposomal membrane have been studied by measurements of lipid peroxides, conjugated diene and fluorescence polarization. Predominantly unilamellar phospholipid vesicles prepared by sonication procedure were subjected to radiation doses of {gamma}-rays from Co-60 in aerated, buffered aqueous suspensions. The oxidative damage in irradiated lipid molecules of liposomes has been determined spectrophotometrically by diene conjugate formation and thiobarbituric acid reactive (TBAR) method as a function of radiation dose. A correlation was found between the radiation dose applied (0.1-1 kGy) and the consequent lipid oxidation. The damage produced in irradiated liposomal membrane was measured by 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence decay and polarization. The observed decrease in DPH fluorescence and increase in polarization was found dependent on the radiation dose suggesting alterations in rigidity or organizational order in phospholipid bilayer after irradiation. Furthermore, irradiated liposome vesicles composed of cholesterol showed marked reduction in observed radiation mediated peroxide formation and significantly affected the DPH fluorescence parameters. The magnitude of these modifying effects were found dependent on the mole fraction of cholesterol. It is concluded that modulation of structural order in unilamellar vesicle membrane by variations in basic molecular components controlled the magnitude of lipid peroxidation and diene conjugate formation. These observations contribute to our understanding of mechanism of radical reaction mediated damage caused by ionizing radiation in phospholipid membrane.

  11. Radiation-induced sarcomas of the chest wall

    International Nuclear Information System (INIS)

    Souba, W.W.; McKenna, R.J. Jr.; Meis, J.; Benjamin, R.; Raymond, A.K.; Mountain, C.F.

    1986-01-01

    Sixteen patients are presented who had sarcomas of the chest wall at a site where a prior malignancy had been irradiated. The first malignancies included breast cancer (ten cases), Hodgkin's disease (four cases), and others (two cases). Radiation doses varied from 4200 to 5500 R (mean, 4900 R). The latency period ranged from 5 to 28 years (mean, 13 years). The histologic types of the radiation-induced sarcomas were as follows: malignant fibrous histiocytoma, nine cases; osteosarcoma, six cases; and malignant mesenchymoma, one case. The only long-term survivor is alive and well 12 years after resection of a clavicular chondroblastic osteosarcoma. Three cases were recently diagnosed. Despite aggressive multimodality treatment, the remaining 13 patients have all died from their sarcomas (mean survival, 13.5 months). All patients have apparently been cured of their first malignancies. Chemotherapy was ineffective. No treatment, including forequarter amputation, appeared to palliate the patients with supraclavicular soft tissue sarcomas. Major chest wall resection offered good palliation for seven of eight patients with sarcomas arising in the sternum or lateral chest wall. Close follow-up is needed to detect signs of these sarcomas in the ever-increasing number of patients receiving therapeutic irradiation

  12. Prevention of gamma radiation induced anaemia in mice by diltiazem

    International Nuclear Information System (INIS)

    Nunia, V.; Goyal, P.K.

    2004-01-01

    Intraperitoneal administration of diltiazem (DTZ), half an hour prior to whole body gamma irradiation (2.5, 5.0, and 7.5 Gy), showed the protection of animals from radiation-induced anaemia. Radiation exposure significantly (p<0.001) reduced the number of pro- and normoblasts in bone marrow and red blood cell (RBC) counts, hemoglobin (Hb), hematocrit (Hct), and erythropoietin (EPO) level in blood, but increased myeloid/erythroid ratio. At all the radiation doses, the maximum decrease in these values was noted on the 3rd day, followed by a gradual recovery from the 7th day, but it was not recorded as normal even until the end of experimentation. In animals pretreated with DTZ, these values were measured higher at all the time periods in comparison to corresponding control, and these were almost normal at the last autopsy interval only at 2.5 Gy radiation dose. DTZ maintained the higher EPO level in blood, which acted on bone marrow and spleen colony forming unit for erythroblast (CFU-E), and stimulated such cells to produce RBCs. These results confirm that DTZ has the potency to alter anaemic condition favorably through the protection of bone marrow stem cells, and subsequently it maintains the higher number of pro-and normoblasts in bone marrow, RBC counts, Hb, Hct percentage, and EPO level in blood and the lower myeloid/erythroid ratio in bone marrow. (author)

  13. An accidental poisoning with mitragynine.

    Science.gov (United States)

    Karinen, Ritva; Fosen, Jan Toralf; Rogde, Sidsel; Vindenes, Vigdis

    2014-12-01

    An increasing number of drugs of abuse are sold word wide over the internet. Names like "legal highs", "herbal highs" etc. give the impression that these are safe products, although the risk of fatal reactions might be substantial. Leaves from the plant Mitragyna speciosa, contain active compounds like mitragynine and 7-hydroxymitragynine. It has been reported that the potency of 7-hydroxymitragynine at the μ-opioid receptor is 30 times higher than that of mitragynine and 17 times higher than that of morphine. Case reports regarding poisoning with Kratom are reported, but the toxic or lethal ranges for the concentrations of the active substances have not been established, and concentrations of 7-hydroxymitragynine have not been reported previously. We present a case report where a middle aged man was found dead at home. The deceased had a history of drug abuse and mental illness for several years. At autopsy, there were no significant pathological findings. Post-mortem analysis of peripheral blood revealed: zopiclone 0.043mg/L, citalopram 0.36mg/L and lamotrigine 5.4mg/L, i.e. concentrations regularly seen after therapeutic ingestion of these drugs. Additionally mitragynine 1.06mg/L and 7-hydroxymitragynine 0.15mg/L were detected in blood and both also in urine. The high concentrations of mitragynine and 7-hydroxymitragynine indicate that the cause of death is intoxication by these substances; and the circumstances point toward the manner of death being accidental. We recommend that both mitragynine and 7-hydroxymitragynine are analyzed for in cases with suspected Kratom intoxication. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Hematopoietic stem cells under pressure.

    Science.gov (United States)

    Ganuza, Miguel; McKinney-Freeman, Shannon

    2017-07-01

    Hematopoietic stem cells (HSCs) and progenitors are tasked with maintaining hematopoietic homeostasis in the face of numerous insults and challenges, including infection, inflammation, and exsanguination. HSCs possess the remarkable ability to reconstitute the entire hematopoietic system of an organism whose own hematopoietic system has been ablated. This ability is exploited routinely in the clinic via HSC transplantation (HSCT). Here, we focus on the physiological and molecular bottlenecks overcome by HSCs during transplantation. During transplantation, HSCs encounter a damaged bone marrow niche, characterized molecularly by increases in oxygen concentrations and an altered cytokine milieu. New mechanisms and pathways have been recently implicated during HSCT, including transplanted HSC-dependent secretion of conditioning molecules that facilitate engraftment and pathways that protect HSCs from perturbed organelle homeostasis. Better understanding the molecular processes HSCs employ to withstand the stress of transplant will illuminate novel targets for further improving conditioning regimens and engraftment during HSCT.

  15. Thrombopoietin and hematopoietic stem cells

    OpenAIRE

    de Graaf, Carolyn A; Metcalf, Donald

    2011-01-01

    Thrombopoietin (TPO) is the cytokine that is chiefly responsible for megakaryocyte production but increasingly attention has turned to its role in maintaining hematopoietic stem cells (HSCs). HSCs are required to initiate the production of all mature hematopoietic cells, but this differentiation needs to be balanced against self-renewal and quiescence to maintain the stem cell pool throughout life. TPO has been shown to support HSC quiescence during adult hematopoiesis, with the loss of TPO s...

  16. Effect of epicatechin against radiation-induced oral mucositis: in vitro and in vivo study.

    Directory of Open Access Journals (Sweden)

    Yoo Seob Shin

    Full Text Available PURPOSE: Radiation-induced oral mucositis limits the delivery of high-dose radiation to head and neck cancer. This study investigated the effectiveness of epicatechin (EC, a component of green tea extracts, on radiation-induced oral mucositis in vitro and in vivo. EXPERIMENTAL DESIGN: The effect of EC on radiation-induced cytotoxicity was analyzed in the human keratinocyte line HaCaT. Radiation-induced apoptosis, change in mitochondrial membrane potential (MMP, reactive oxygen species (ROS generation and changes in the signaling pathway were investigated. In vivo therapeutic effects of EC for oral mucositis were explored in a rat model. Rats were monitored by daily inspections of the oral cavity, amount of oral intake, weight change and survival rate. For histopathologic evaluation, hematoxylin-eosin staining and TUNEL staining were performed. RESULTS: EC significantly inhibited radiation-induced apoptosis, change of MMP, and intracellular ROS generation in HaCaT cells. EC treatment markedly attenuated the expression of p-JNK, p-38, and cleaved caspase-3 after irradiation in the HaCaT cells. Rats with radiation-induced oral mucositis showed decreased oral intake, weight and survival rate, but oral administration of EC significantly restored all three parameters. Histopathologic changes were significantly decreased in the EC-treated irradiated rats. TUNEL staining of rat oral mucosa revealed that EC treatment significantly decreased radiation-induced apoptotic cells. CONCLUSIONS: This study suggests that EC significantly inhibited radiation-induced apoptosis in keratinocytes and rat oral mucosa and may be a safe and effective candidate treatment for the prevention of radiation-induced mucositis.

  17. Bevacizumab alleviates radiation-induced brain necrosis: A report of four cases

    Directory of Open Access Journals (Sweden)

    Li Xiang-Pan

    2015-01-01

    Full Text Available To analyze the therapeutic effect of bevacizumab on radiation-induced brain necrosis. Four radiation-induced brain necrosis patients, administered with bevacizumab at a dose of 7.5 mg/kg every 3 weeks, 2 times. One case of brain metastasis of lung cancer and one case of nasopharyngeal carcinoma with brain necrosis after radiotherapy. However, their physical signs disappeared after the treatment with bevacizumab. One case of brainstem lesion and one case of brain glioma patient showed a transient improvement in signs and symptoms after treatment with bevacizumab. Bevacizumab can significantly alleviate the radiation-induced brain edema, and can improve the symptoms successively.

  18. Mortalidad intrahospitalaria por accidente cerebrovascular

    Directory of Open Access Journals (Sweden)

    Federico Rodríguez Lucci

    2013-08-01

    Full Text Available La mortalidad global por accidente cerebrovascular (ACV ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Stroke de FLENI y los registros institucionales de mortalidad entre los años 2000 y 2010. Los subtipos de ACV isquémicos se clasificaron según criterios TOAST y los ACV hemorrágicos en hematomas intrapanquimatosos, hemorragias subaracnoideas aneurismáticas, malformaciones arteriovenosas y otros hematomas intraparenquimatosos. Se analizaron 1514 pacientes, 1079 (71% con ACV isquémico (grandes vasos 39%, cardioembólicos 27%, lacunares 9%, etiología indeterminada 14%, otras etiologías 11% y 435 (29% con ACV hemorrágico (intraparenquimatosos 27%, hemorragia subaracnoidea 30%, malformaciones arteriovenosas 25% y otros hematomas espontáneos 18%. Se registraron 38 muertes intrahospitalarias (17 ACV isquémicos y 21 ACV hemorrágicos, representando una mortalidad global del 2.5% (1.7% en ACV isquémicos y 4.8% en ACV hemorrágicos. No se registraron muertes asociadas al uso de fibrinolíticos endovenosos. La mortalidad intrahospitalaria en pacientes con ACV isquémico y hemorrágico en nuestro centro fue baja. El manejo en un centro dedicado a las enfermedades neurológicas y el enfoque multidisciplinario por personal médico y no médico entrenado en el cuidado de la enfermedad cerebrovascular podrían explicar, al menos en parte, estos resultados.

  19. Radiation induced hepatic lesions and their amelioration by Rosemarinus oficinalis

    International Nuclear Information System (INIS)

    SoyaI, Dhanraj; Goyal, P.K.

    2013-01-01

    autopsy interval (i.e. 30 days), only in experimental group. On contrary, abnormal hepatocytes increased up to day 5 after irradiation. Binucleated hepatocytes showed a biphasic mode of elevation after irradiation, first on day 2 then on day 10 post-treatment in both the groups, but the same was comparatively less marked in experimental group. Several radiation induced hepatic lesions were also visualized in both the groups, but in ROE + radiation treated group, the degree of damage was found to be considerably lesser and the recovery from such lesions was much faster to regain the normal architecture of liver. Hence, the results from the present study suggest that Rosemarinus officinalis leaves extract pretreatment provides protection against radiation-induced histopathological alterations in liver of mammals. (author)

  20. 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

  1. Multiple factors participating in radiation-induced adaptive response

    International Nuclear Information System (INIS)

    Nenoi, Mitsuru; Vares, G.; Wang, Bing

    2009-01-01

    Radiation-induced adaptive response (RAR) is essentially the acquisition of radiation resistance by pre-exposed low dose radiation (priming). In this paper, in vitro findings on RAR-related factors are reviewed and authors' studies of RAR-related gene analysis in lethality and malformation of mouse fetus are described for future view. Studies on in vitro RAR have involved such participating factors as signal transduction, response appearance and bystander effect, and gene expression profiling. In RAR, DNA double strand break (DSB) by priming is conceivably the initial stimulation. In various cell systems including p53-knockout cells and in enzyme inhibition studies, intracellular signaling factors like protein kinase C, p38 MAPK, phospholipase C have been shown to participate. Increased activities of antioxidant and of damaged DNA repairing system, modulation of cell cycle, heat-shock reactions and apoptosis are suggested to concern to RAR appearance. Relationship between RAR and bystander effect is conceived to be important based on findings of cell lethality, mutagenesis, gap junction and NO radical. Genes relating to DSB repair, stress response, cell cycle and apoptosis have been shown to be specifically changed in RAR by their expression profile. Authors have conducted in vivo studies on RAR using embryogenetic system in the mouse. They have shown by gene profiling that signaling evoked by priming is important when the fetal lethality and malformation are used as RAR measures, and that in the subsequent process to RAR appearance, many signaling factors, particularly the transcription factor like p53, play a role. Database construction according to measures employed in individual studies, classification of living systems studied, radiation factors like linear energy transfer (LET), dose and dose rate, and functional genes concerned is thought useful for understanding the ultimate molecular mechanisms involved in ARA. (K.T.)

  2. Case of radiation induced carcinoma of the cervical esophagus

    Energy Technology Data Exchange (ETDEWEB)

    Iwase, K.; Miura, K.; Kawase, K.; Yamaguchi, A.; Kondo, S. (Fujita-Gakuen Univ., Nagoya (Japan). School of Medicine)

    1980-07-01

    A patient with carcinoma of the cervical esophagus who visited a hospital with a complaint of difficulty in swallowing was reported. This patient was a 50 year old woman. It was 32 years since she had had external irradiation with x- ray over the neck for Basedow's disease at the age of 18. From the age of 30, she had had hypothyroidism and had used thyroid. She became aware of difficulty in swallowing in October, 1976. Then this symptom progressed gradually, and she also had hoarseness. She visited a hospital in August, 1977. At the first medical examination, pigmentation and atrophic changes in the neck induced by radiation were observed, and some lymphnodes with the size of a red bean were palpated. Esophageal roentogenography revealed circular and spiral type lesion in the cervical esophagus, which was 4 cm in length and had a clear boundary. Endoscopic examination revealed circular stenotic lesion. This lesion was diagnosed as squamous cell carcinoma by biopsy. Total of 3,000 rad of Linac x-ray was irradiated over the neck and the clavicle before operation. Operation findings revealed fibrosis, atrophy, and hardening of the thyroid gland caused by radiation. Carcinoma with the size 35 mm x 18 mm was limited to the cervical esophagus, and the degree of the progress was A/sub 2/, N/sub 2/, M/sub 0/ (Pl/sub 0/). Histological findings revealed moderately differentiated squamous cell carcinoma and its metastases to the right supraclaviclar lymphnodes. This carcinoma was diagnosed as radiation-induced carcinoma of the cervical esophagus, because this patient had had irradiation over the neck, locally marked atrophic changes and scar remained, and carcinoma occurred in the area which had been irradiated with x-ray.

  3. A comparative review of radiation-induced cancer risk models

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Hee; Kim, Ju Youl [FNC Technology Co., Ltd., Yongin (Korea, Republic of); Han, Seok Jung [Risk and Environmental Safety Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2017-06-15

    With the need for a domestic level 3 probabilistic safety assessment (PSA), it is essential to develop a Korea-specific code. Health effect assessments study radiation-induced impacts; in particular, long-term health effects are evaluated in terms of cancer risk. The objective of this study was to analyze the latest cancer risk models developed by foreign organizations and to compare the methodology of how they were developed. This paper also provides suggestions regarding the development of Korean cancer risk models. A review of cancer risk models was carried out targeting the latest models: the NUREG model (1993), the BEIR VII model (2006), the UNSCEAR model (2006), the ICRP 103 model (2007), and the U.S. EPA model (2011). The methodology of how each model was developed is explained, and the cancer sites, dose and dose rate effectiveness factor (DDREF) and mathematical models are also described in the sections presenting differences among the models. The NUREG model was developed by assuming that the risk was proportional to the risk coefficient and dose, while the BEIR VII, UNSCEAR, ICRP, and U.S. EPA models were derived from epidemiological data, principally from Japanese atomic bomb survivors. The risk coefficient does not consider individual characteristics, as the values were calculated in terms of population-averaged cancer risk per unit dose. However, the models derived by epidemiological data are a function of sex, exposure age, and attained age of the exposed individual. Moreover, the methodologies can be used to apply the latest epidemiological data. Therefore, methodologies using epidemiological data should be considered first for developing a Korean cancer risk model, and the cancer sites and DDREF should also be determined based on Korea-specific studies. This review can be used as a basis for developing a Korean cancer risk model in the future.

  4. Treatment of radiation-induced normal tissue lesions

    International Nuclear Information System (INIS)

    Rezvani, M.

    2003-01-01

    Normal tissue damage is the most important limiting factor in radiotherapy. It must be possible, at least theoretically, to eradicate a localised tumour if a large enough dose of radiation could be delivered to tumour, however, practically, there is always the danger of damaging normal tissues adjacent to the tumour. Factors such as the total radiation dose, overall treatment time, dose per fraction, dose-rate and the effects of changing the irradicated volume of the spinal cord have been examined in order to improve therapeutic ratio in radiotherapy. The majority of these studies have concentrated on optimizing dose fractionation schedules. Only recently have attempts been made to modify this effect by the administration of therapeutic agents after irradiation but before the development of the lesion. Despite this interest the problem still exists. At present there is no effective clinically applied treatment towards radiation-induced normal tissue injury, however, some symptoms for example swelling or pain during inflammatory phase may respond to corticosteroids. There are a number of agents, which have been used experimentally, some clinically, to alleviate radiation damage. The results of these studies are reviewed. A number of substances, generally named Biological Response Modifiers, with diverse mode of actions have been used in post irradiation modification of normal tissue reactions. The effect and mode of action of a number of these treatments are discussed. Classical radioprotectors, that are mainly thiol-containing substances such as Amifostine, are used for prophylaxis and should be administered before or at the time of irradiation. These substances have been deliberately excluded in this article

  5. Radiation-induced adaptive response in human lymphoblast

    International Nuclear Information System (INIS)

    Yatagai, Fumio; Sugasawa, Kaoru

    2009-01-01

    Described are the genetic analysis of variant strains obtained by the optimal condition for radiation-induced adaptive response (AR), and molecular elucidation of the suppression of concomitant mutation. The TK6 cells (heterozygous thymidine kinase, +/-) were used for detection of mutation by loss of heterozygosity (LOH). The optimal conditions for reducing the mutation by subsequent irradiation (SI) to its rate of about 60% (vs control 100%, no PI) were found to be 5 cGy of pre-irradiation (PI) of X-ray and 2 Gy of SI with the interval of 6 hr, where mutated cells were of non-LOH type in around 25% and homo-LOH type by homologous recombination (HR) in 60%. By cDNA sequencing, the former cells having changed bases were found to be in variant strain ratio of 1/8 vs control 7/18, suggesting that the mutation was decreased mainly by suppression of base change. Expression of XPC protein, an important component for recognition of the base damage in global genome nucleotide excision repair, was studied by Western blotting as the possible mechanism of suppressing the mutation, which revealed different time dynamics of the protein in cells with PI+SI and SI alone (control). To see the effect of PI on the double strand break (DSB) repair, cells with PI were infected with restriction enzyme I-SceI vector to yield DSB instead of SI, which revealed more efficient repair (70% increase) by HR than control, without significant difference in non-homologous end-joining repair. Micro-array analysis to study the gene expression in the present experimental conditions for AR is in progress. The TK6 cells used here were thought useful for additional studies of the mechanism of AR as mutation by direct or indirect irradiation can be tested. (K.T.)

  6. Pentoxifylline in the treatment of radiation-induced fibrosis.

    Science.gov (United States)

    Okunieff, Paul; Augustine, Elizabeth; Hicks, Jeanne E; Cornelison, Terri L; Altemus, Rosemary M; Naydich, Boris G; Ding, Ivan; Huser, Amy K; Abraham, Edward H; Smith, Judith J; Coleman, Norman; Gerber, Lynn H

    2004-06-01

    Fibrotic sequelae remain the most important dose-limiting toxicity of radiation therapy to soft tissue. Functionally, this is reflected in loss of range of motion and muscle strength and the development of limb edema and pain. Tumor necrosis factor alpha and fibroblast growth factor 2 (FGF2), which are abnormally elevated in irradiated tissues, may mediate radiation fibrovascular injury. In an open label drug trial, we studied the effects of pentoxifylline (400 mg orally tid for 8 weeks) on 30 patients who displayed late, radiation-induced fibrosis at 1 to 29 years posttreatment (40 to 84 Gy). The primary outcome measurement was change in physical impairments thought to be secondary to radiation, including active and passive range of motion (AROM and PROM), muscle strength, limb edema, and pain. Plasma levels of cytokines (tumor necrosis factor alpha and FGF2) also were measured. Twenty-seven patients completed baseline and 8-week assessments, and 24 patients completed baseline, 8-week, and 16-week assessments. After 8 weeks of pentoxifylline intervention, 20 of 23 patients with impaired AROM and 19 of 22 with impaired PROM improved; 11 of 19 patients with muscle weakness showed improved motor strength; five of seven patients with edema had decreased limb girth; and nine of 20 patients had decreased pain. Pretreatment FGF2 levels dropped from an average of 44.9 pg/mL to 24.0 pg/mL after 8 weeks of treatment. Patients receiving pentoxifylline demonstrated improved AROM, PROM, and muscle strength and decreased limb edema and pain. Reversal of these delayed radiation effects was associated with a decrease in circulating FGF2.

  7. Radiation-induced apoptosis and developmental disturbance of the brain

    International Nuclear Information System (INIS)

    Inouye, Minoru

    1995-01-01

    The developing mammalian brain is highly susceptible to ionizing radiation. A significant increase in small head size and mental retardation has been noted in prenatally exposed survivors of the atomic bombing, with the highest risk in those exposed during 8-15 weeks after fertilization. This stage corresponds to day 13 of pregnancy for mice and day 15 for rats in terms of brain development. The initial damage produced by radiation at this stage is cell death in the ventricular zone (VZ) of the brain mantle, the radiosensitive germinal cell population. During histogenesis of the cerebellum the external granular layer (EGL) is also radiosensitive. Although extensive cell death results in microcephaly and histological abnormlity, both VZ and EGL have an ability to recover from a considerable cell loss and form the normal structure of the central nervous system. The number of cell deaths to induce tissue abnormalities in adult brain rises in the range of 15-25% of the germinal cell population; and the threshold doses are about 0.3 Gy for cerebral defects and 1 Gy for cerebellar anomalies in both mice and rats. A similar threshold level is suggested in human cases in induction of mental retardation. Radiation-induced cell death in the VZ and EGL has been revealed as apoptosis, by the nuclear and cytoplasmic condensation, transglutaminase activation, required macromolecular synthesis, and internucleosomal DNA cleavage. Apoptosis of the germinal cell is assumed to eliminate acquired genetic damage. Once an abnormality in DNA has been induced and fixed in a germinal cell, it would be greatly amplified during future proliferation. These cells would commit suicide when injured for replacement by healthy cells, rather than undertake DNA repair. In fact they show very slow repair of cellular damage. Thus the high sensitivity of undifferentiated neural cells to the lethal effect of radiation may constitute a biological defense mechanism. (author) 69 refs

  8. Simvastatin attenuates radiation-induced salivary gland dysfunction in mice

    Directory of Open Access Journals (Sweden)

    Xu L

    2016-07-01

    Full Text Available Liping Xu,* Xi Yang,* Jiayan Chen, Xiaolin Ge, Qin Qin, Hongcheng Zhu, Chi Zhang, Xinchen Sun Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, People’s Republic of China *These authors contributed equally to this work Objective: Statins are widely used lipid-lowering drugs, which have pleiotropic effects, such as anti-inflammation, and vascular protection. In our study, we investigated the radioprotective potential of simvastatin (SIM in a murine model of radiation-induced salivary gland dysfunction. Design: Ninety-six Institute of Cancer Research mice were randomly divided into four groups: solvent + sham irradiation (IR (Group I, SIM + sham IR (Group II, IR + solvent (Group III, and IR + SIM (Group IV. SIM (10 mg/kg body weight, three times per week was administered intraperitoneally 1 week prior to IR through to the end of the experiment. Saliva and submandibular gland tissues were obtained for biochemical, morphological (hematoxylin and eosin staining and Masson’s trichrome, and Western blot analysis at 8 hours, 24 hours, and 4 weeks after head and neck IR. Results: IR caused a significant reduction of salivary secretion and amylase activity but elevation of malondialdehyde. SIM remitted the reduction of saliva secretion and restored salivary amylase activity. The protective benefits of SIM may be attributed to scavenging malondialdehyde, remitting collagen deposition, and reducing and delaying the elevation of transforming growth factor β1 expression induced by radiation. Conclusion: SIM may be clinically useful to alleviate side effects of radiotherapy on salivary gland. Keywords: simvastatin, radiation protection, submandibular gland, transforming growth factor-β1, mice

  9. Radiation-Induced Phase Transformations in Ilmenite-Group Minerals

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, J. N.

    1997-12-31

    Transmission electron microscopy (TEM) is a powerful tool for characterizing and understanding radiation-induced structural changes in materials. We have irradiated single crystals of ilmenite (FeTiO{sub 3}) and geikielite (MgTiO{sub 3}) using ions and electrons to better understand the response of complex oxides to radiation. Ion irradiation experiments of bulk single crystals at 100 K show that ilmenite amorphized at doses of less than 1x10(exp15) Ar(2+)/sq cm and at a damage level in the peak damage region of 1 displacement per atom (dpa). Transmission electron microscopy and electron diffraction of a cross-sectioned portion of this crystal confirmed the formation of a 150 am thick amorphous layer. Geikielite proved to be more radiation resistant, requiring a flux of 2x10(exp 15) Xe(2+)/sq cm to induce amorphization at 100 K. This material did not amorphize at 470 K, despite a dose of 2.5 x10(exp 16) Xe(2+)/sq cm and a damage level as high as 25 dpa. Low temperature irradiations of electron- transparent crystals with 1 MeV Kr(+) also show that ilmenite amorphized after a damage level of 2.25 dpa at 175 K.Similar experiments on geikielite show that the microstructure is partially amorphous and partially crystalline after 10 dpa at 150 K. Concurrent ion and electron irradiation of both materials with 1 MeV Kr(+) and 0.9 MeV electrons produced dislocation loops in both materials, but no amorphous regions were formed. Differences in the radiation response of these isostructural oxides suggests that in systems with Mg-Fe solid solution, the Mg-rich compositions may be more resistant to structural changes.

  10. ATM Mutations and the Development of Severe Radiation-Induced Morbidity Following Radiotherapy for Breast Cancer

    National Research Council Canada - National Science Library

    Rosenstein, Barry

    2003-01-01

    The hypothesis being tested in this project is that a greater proportion of patients who develop radiation-induced RTOG/EORTC grade 3/4 subcutaneous late tissue morbidity possess a mutated ATM gene...

  11. Design Methodologies and to Combat Radiation Induced Corruption in FPGAs and SoCs, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Traditional radiation hardened by process (RHBP) and radiation hardened by design (RHBD) techniques have seen success in mitigating the effects of radiation induced...

  12. ATM Mutations and the Development of Severe Radiation-Induced Morbidity Following Radiotherapy for Breast Cancer

    National Research Council Canada - National Science Library

    Rosenstein, Barry

    2004-01-01

    The hypothesis being tested in this project is that a greater proportion of patients who develop radiation-induced subcutaneous late tissue morbidity possess a variant allele in the ATM gene compared...

  13. Experimental analysis of recombination and neutralization of radiation-induced charges, using isochronal annealing

    International Nuclear Information System (INIS)

    Quittard, O.; Brisset, C.; Joffre, F.; Oudea, C.; Saigne, F.; Dusseau, L.; Fesquet, J.; Gasiot, J.

    1999-01-01

    The experimental analysis described in this paper made use of the isochronal principle to carry out qualitative and quantitative studies of both aspects of the RICN mechanism (radiation-induced charge neutralization) : recombination and compensation. (authors)

  14. Modelling ionising radiation induced defect generation in bipolar oxides with gated diodes

    International Nuclear Information System (INIS)

    Barnaby, H.J.; Cirba, C.; Schrimpf, R.D.; Kosier, St.; Fouillat, P.; Montagner, X.

    1999-01-01

    Radiation-induced oxide defects that degrade electrical characteristics of bipolar junction transistor (BJTs) can be measured with the use of gated diodes. The buildup of defects and their effect on device radiation response are modeled with computer simulation. (authors)

  15. Naturally occurring and radiation-induced tumors in SPF mice, and genetic influence in radiation leukemogenesis

    International Nuclear Information System (INIS)

    Kasuga, T.

    1979-01-01

    The data obtained so far in this study point to a strong genetic influence not only on the types and incidence of naturally occurring and radiation-induced tumors but also on radiation leukemogenesis. (Auth.)

  16. 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...

  17. Design Methodologies and to Combat Radiation Induced Corruption in FPGAs and SoCs Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Traditional radiation hardened by process (RHBP) and radiation hardened by design (RHBD) techniques have seen success in mitigating the effects of radiation induced...

  18. Effect of bacterial lipopolysaccharide preparations of hemopoiesis in ionizing radiation-induced depression of hemopoiesis

    International Nuclear Information System (INIS)

    Baranov, M.N.; Golubeva, L.A.; Martirosov, K.S.; Petkevich, N.V.

    1986-01-01

    The therapeutic effects of pyrogend and prodigiosan in radiation-induced depression of hemopoiesis were intestigated in tests on guinea pigs. Both the preparations were shown to produce. The stimulating effect on the postradiation recovery of granulocytopoiesis and lymphopoiesis

  19. RADIATION-INDUCED SARCOMA OF CHEST WALL FOLLOWING BREAST CANCER THERAPY

    Directory of Open Access Journals (Sweden)

    Yousef Valizadeh

    1995-06-01

    Full Text Available A woman patient who had received external radiotherapyfor breast cancer developed secondary tumor in the irradiated area after nineyears. We offer our observation on this case which seems to be radiation-induced sarcoma

  20. Radiation-induced osteosarcoma 17 years after mediastinal irradiation following surgical removal of thymoma

    International Nuclear Information System (INIS)

    Kadota, Yoshihisa; Utsumi, Tomoki; Inoue, Masayoshi; Sawabata, Noriyoshi; Minami, Masato; Okumura, Meinoshin

    2010-01-01

    Radiation-induced osteosarcoma is a rare complication after irradiation of primary malignancies. In the chest wall, it is usually secondary to radiotherapy for breast cancer or lymphoma. We report a rare case of radiation-induced osteosarcoma of the sternum after mediastinal irradiation of a thymoma. A 49-year-old woman presented with a sternal tumor 17 years after surgery plus mediastinal irradiation (50 Gy) for a stage III thymoma. On biopsy, this second tumor was diagnosed as a radiation-induced osteosarcoma. Systemic survey revealed additional metastatic spread to vertebrae and pelvis. Despite intensive combination chemotherapy that initially stabilized her disease, the patient died 2 years after the diagnosis was made. Because thymoma patients receiving mediastinal irradiation are thus at additional risk of radiation-induced secondary malignancy, long-term follow-up is advisable. (author)

  1. Comparison of gamma radiation - induced effects in two human prostate cancer cells

    International Nuclear Information System (INIS)

    Vucic, V.; Adzic, M.; Ruzdijic, S.; Radojcic, M.B. . E-mail address of corresponding author: vesnav@vin.bg.ac.yu; Vucic, V.)

    2005-01-01

    In this study, the effects of gamma radiation on two hormone refractory human prostate cancer cell lines, DU 145 and PC-3, were followed. It was shown that gamma radiation induced significant inhibition of cell proliferation and viability in dose dependent manner. Antiproliferative effects of radiation were similar in both cell lines, and more pronounced than cytotoxic effects. In addition to that, PC-3 cell line was more resistant to radiation -induced cytotoxicity. (author)

  2. 311 Pathogenesis of Radiation-induced Pneumonitis in Patients with Chronic Obstructive Pulmonary Disease

    OpenAIRE

    Politi, Ekaterini; Tolia, Maria; Makrilia, Nektaria; Psarros, Fotis; Dannos, Ioannis; Syrigos, Kostas N.; Syrigou, Ekaterini

    2012-01-01

    Background Chest radiation is a common therapeutic approach in the management of lung cancer, as well as in other malignancies, rendering radiation-induced pneumonitis a rather commonly reported adverse event. A large proportion of patients undergoing radiation have underlying chronic obstructive pulmonary disease (COPD). We aim to elucidate the pathogenetic pathways implicated in radiation-induced pneumonitis particularly in this subgroup of patients. Methods A literature search was performe...

  3. Inflammatory markers of radiation-induced late effects

    International Nuclear Information System (INIS)

    Dubner, D.; Gallegos, C.; Michelin, S.; Portas, M.

    2011-01-01

    Up to now there is no established parameters for the follow-up of delayed radiation injuries. Late toxicity is generally irreversible and can have devastating effects on quality of life of people exposed either accidentally or during therapeutic radiation treatments. Histologically, late manifestations of radiation damage include fibrosis, necrosis, atrophy and vascular lesions. Although many etiologies have been suggested regarding these late toxicities, persistent inflammation has been described as playing a key role. The recruitment of leukocytes from circulating blood is decisive in the inflammatory reaction. All the steps in the recruitment cascade are orchestrated by cell-adhesion molecules (CAMs) on both leukocytes and endothelial cells, and different subsets of CAMs are responsible for different steps in extravasation. A link between radiation –induced inflammatory processes and alterations in T-cell immunity are still demonstrable in the blood of A-bomb survivors. The following study was conducted to examine the response of the immune system in the inflammatory reactions in patients with late skin injuries after radiotherapy or interventional fluoroscopy procedures. The expression of adhesion molecules ICAM1 and β1-integrin on granulocytes and lymphocytes, as well as changes in subpopulations of T lymphocytes and the level of C-reactive protein, a well- studied inflammatory marker were evaluated. (authors)

  4. Ophthalmic Manifestations of Hematopoietic Malignancy

    Directory of Open Access Journals (Sweden)

    Natsuyo Yoshida-Hata

    2016-01-01

    Full Text Available Purpose. To report the ocular findings in patients with hematopoietic malignancy with optic nerve involvement and abducens nerve palsy. Methods. The medical records of all cases of hematopoietic cancer with ophthalmic involvements seen in the Department of Ophthalmology of the National Center for Global Health and Medicine between 2009 and 2014 were reviewed. Results. Eight patients with hematopoietic cancer with optic nerve invasion or abducens nerve palsy were studied. The primary diseases were 3 cases of multiple myeloma, 1 case of acute lymphocytic leukemia, 1 case of follicular lymphoma, and 3 cases of AIDS-related lymphoma. Six cases had optic nerve invasion, 2 cases had abducens nerve palsy, and 1 case had optic nerve invasion of both eyes. The median visual acuity of eyes with optic nerve invasion was 0.885 logarithm of the minimum angle of resolution (logMAR units. The final visual acuity of eyes with optic nerve invasion was 1.25 logMAR units, and that of those with sixth-nerve palsy was −0.1 logMAR units. Six cases died during the five-year follow-up period. An ophthalmic involvement in patients with hematopoietic cancer, especially AIDS-related lymphoma, was associated with poor prognosis. Conclusion. Because ophthalmic involvement in patients with hematopoietic malignancy has a poor prognosis, an early diagnosis of the cancers by the ophthalmologic findings by ophthalmologists could improve the prognosis.

  5. Pyruvate metabolism: A therapeutic opportunity in radiation-induced skin injury

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Hyun; Kang, Jeong Wook [Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Lee, Dong Won [Department of Plastic Surgery, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Oh, Sang Ho [Department of Dermatology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Lee, Yun-Sil [College of Pharmacy & Division of Life and Pharmaceutical Sciences, Ewah Womans University, Seoul 120-750 (Korea, Republic of); Lee, Eun-Jung [Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Cho, Jaeho, E-mail: jjhmd@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of)

    2015-05-08

    Ionizing radiation is used to treat a range of cancers. Despite recent technological progress, radiation therapy can damage the skin at the administration site. The specific molecular mechanisms involved in this effect have not been fully characterized. In this study, the effects of pyruvate, on radiation-induced skin injury were investigated, including the role of the pyruvate dehydrogenase kinase 2 (PDK2) signaling pathway. Next generation sequencing (NGS) identified a wide range of gene expression differences between the control and irradiated mice, including reduced expression of PDK2. This was confirmed using Q-PCR. Cell culture studies demonstrated that PDK2 overexpression and a high cellular pyruvate concentration inhibited radiation-induced cytokine expression. Immunohistochemical studies demonstrated radiation-induced skin thickening and gene expression changes. Oral pyruvate treatment markedly downregulated radiation-induced changes in skin thickness and inflammatory cytokine expression. These findings indicated that regulation of the pyruvate metabolic pathway could provide an effective approach to the control of radiation-induced skin damage. - Highlights: • The effects of radiation on skin thickness in mice. • Next generation sequencing revealed that radiation inhibited pyruvate dehydrogenase kinase 2 expression. • PDK2 inhibited irradiation-induced cytokine gene expression. • Oral pyruvate treatment markedly downregulated radiation-induced changes in skin thickness.

  6. Immunohistochemical study of p53 overexpression in radiation-induced colon cancers

    International Nuclear Information System (INIS)

    Minami, Kazunori; Hayashi, Nobuyuki; Mokarim, A.; Matsuzaki, Sumihiro; Ito, Masahiro; Sekine, Ichiro.

    1998-01-01

    The expressions of p53 and proliferating cell nuclear antigen (PCNA) were studied immunohistochemically from paraffin sections of 7 cases (9 lesions) of radiation-induced colon cancer and 42 cases of spontaneous colon cancer. Age distribution of radiation-induced and spontaneous colon cancer were 68.1 years (range, 56 to 77 years) and 67.4 years (range, 31 to 85 years), respectively. Among the radiation-induced colon cancers, there were 3 lesions of mucinous carcinoma (33%), a much higher than found for spontaneous mucinous cancer. Immunohistochemically, p53 protein expression was detected in 7/9 (78%) of radiation-induced cancers and in 23/42 (55%) of spontaneous colon cancers. χ 2 analysis found no significant differences between radiation-induced and spontaneous colon cancers in age distribution or p53-positive staining for frequency, histopathology, or Dukes'' classification. In radiation colitis around the cancers including aberrant crypts, spotted p53 staining and abnormal and scattered PCNA-positive staining were observed. In histologically normal cells, p53 staining was almost absent and PCNA-positive staining was regularly observed in the lower half of the crypt. In radiation colitis including aberrant glands, cellular proliferation increased and spotted p53 expression was observed. This study suggests that radiation colitis and aberrant glands might possess malignant potential and deeply associate with carcinogenesis of radiation-induced colon cancer. (author)

  7. Targets for, and consequences of, radiation-induced chromosomal instability

    Science.gov (United States)

    Kaplan, Mark Isaac

    Chromosomal instability has been demonstrated in a human- hamster hybrid cell line, GM10115, after exposure to x- rays. Chromosomal instability in these cells is characterized by the appearance of novel chromosomal rearrangements multiple generations after exposure to ionizing radiation. To identify the cellular target(s) for radiation-induced chromosomal instability, cells were treated with 125I-labeled compounds. Labeling cells with 125I-iododeoxyuridine, which caused radiation damage to the DNA and associated nuclear structures, did induce chromosomal instability. While cell killing and first-division chromosomal rearrangements increased with increasing numbers of 125I decays, the frequency of chromosomal instability was independent of dose. Incorporation of an 125I-labeled protein, 125I-succinyl- concanavalin A, into either the plasma membrane or the cytoplasm, failed to elicit chromosomal instability. These results show that radiation damage to the nucleus, and not to extranuclear regions, contributes to the induction of chromosomal instability. To determine the role of DNA strand breaks as a molecular lesion responsible for initiating chromosomal instability, cells were treated with a variety of DNA strand breaking agents. Agents capable of producing complex DNA double strand breaks, including X-rays, Neocarzinostatin and bleomycin, were able to induce chromosomal instability. In contrast, double strand breaks produced by restriction endonucleases as well as DNA strand breaks produced by hydrogen peroxide failed to induce chromosomal instability. This demonstrates that the type of DNA breakage is important in the eventual manifestation of chromosomal instability. In order to understand the relationship between chromosomal instability and other end points of genomic instability, chromosomally stable and unstable clones were analyzed for sister chromatid exchange, delayed reproductive cell death, delayed mutation, mismatch repair and delayed gene amplification

  8. Radiation-Induced Topological Disorder in Irradiated Network Structures

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, Linn W.

    2002-12-21

    This report summarizes results of a research program investigating the fundamental principles underlying the phenomenon of topological disordering in a radiation environment. This phenomenon is known popularly as amorphization, but is more formally described as a process of radiation-induced structural arrangement that leads in crystals to loss of long-range translational and orientational correlations and in glasses to analogous alteration of connectivity topologies. The program focus has been on a set compound ceramic solids with directed bonding exhibiting structures that can be described as networks. Such solids include SiO2, Si3N4, SiC, which are of interest to applications in fusion energy production, nuclear waste storage, and device manufacture involving ion implantation or use in radiation fields. The principal investigative tools comprise a combination of experimental diffraction-based techniques, topological modeling, and molecular-dynamics simulations that have proven a rich source of information in the preceding support period. The results from the present support period fall into three task areas. The first comprises enumeration of the rigidity constraints applying to (1) more complex ceramic structures (such as rutile, corundum, spinel and olivine structures) that exhibit multiply polytopic coordination units or multiple modes of connecting such units, (2) elemental solids (such as graphite, silicon and diamond) for which a correct choice of polytope is necessary to achieve correct representation of the constraints, and (3) compounds (such as spinel and silicon carbide) that exhibit chemical disorder on one or several sublattices. With correct identification of the topological constraints, a unique correlation is shown to exist between constraint and amorphizability which demonstrates that amorphization occurs at a critical constraint loss. The second task involves the application of molecular dynamics (MD) methods to topologically-generated models

  9. Clinical Experiences with Radiation Induced Thyroid Cancer after Chernobyl

    Directory of Open Access Journals (Sweden)

    Christoph Reiners

    2011-05-01

    Full Text Available The risk of developing thyroid cancer increases considerably after exposure to external or internal radiation, especially in children below the age of 10. After the Chernobyl reactor accident, the yearly incidence of childhood thyroid cancer in Belarus increased to approximately 40 per 1.000.000 in girls and to roughly 20 per 1.000.000 in boys compared to approximately 0.5 cases per 1.000.000 prior to the accident. Typically, young children with thyroid cancer after radiation exposure present in ≈95% of the cases as papillary cancers, in ≈50% as invasive tumors growing outside the thyroid capsule, in ≈65% with lymph node metastases and in ≈15% with distant metastases. A joint Belarusian-German project starting in April 1993 that combined treatment with surgery and radioiodine was organized in 237 selected children from Belarus who were exposed to the Chernobyl fallout and had advanced stages of thyroid cancer. The study group included 141 girls and 96 boys. Their median age at the time of the accident was 1.7 years; whereas the median age at the time of diagnosis was 12.4 years. With the exception of two cases with follicular histology, the majority of the patients had been diagnosed with papillary thyroid cancers. In 63%, the tumor had grown outside the thyroid capsule and invaded the tissue of the neck (pT4. Nearly all of the selected cases (96% showed-up with lymph node metastases (pN1 and 43% of the patients with distant metastases mainly to the lungs (pM1. In 58% of the children, complete remissions of thyroid cancer could be achieved until December 31st 2010 and in 34% of the children, stable partial remissions; in the remaining 8% of the patients, partial remissions were observed. The risk of radiation-induced thyroid cancer increased considerably in children and adolescents who were affected by the Chernobyl reactor accident. In spite of the fact, that thyroid cancers in young children seem to behave more aggressively than in

  10. Andrographolide protects against radiation-induced lung injury in mice

    International Nuclear Information System (INIS)

    Kang Yahui; Wang Jinfeng; Zhang Qu; Huang Guanhong; Ma Jianxin; Yang Baixia; He Xiangfeng; Wang Zhongming

    2014-01-01

    Objective: To investigate the protective effect of andrographolide against radiation-induced lung injury (RILI) in C57BL/6 mice. Methods: Eighty C57BL mice were randomly divided into four groups: un-irradiated and normal saline-treated group (n = 20, control group), un-irradiated and andrographolide-treated group (n = 20, drug group), radiation plus normal saline-treated group (n = 20, radiation group) and radiation plus andrographolide-treated group (n = 20, treatment group). Before radiation, the mice in drug group and treatment group were administered daily via gavage with andrographolide (20 mg·kg -1 ·d -1 )) for 30 d, while the same volume of normal saline solution was given daily in the control and radiation groups. The model of RILI in C57BL mice was established by irradiating whole mouse chest with a single dose of 15 Gy of 6 MV X-rays. The pathological changes of the lung stained with HE/Masson were observed with a light microscope. The transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) in serum were examined by enzyme-linked immunosorbent assay. The activities of malondialdehyde (MDA) and superoxide dismutase (SOD) and the content of hydroxyproline in lung tissues were examined by corresponding kits. Results: Compared with radiation group, there was an obvious amelioration in pathological injury of lung tissue in the treatment group. The lung coefficient, the activities of lung tissue MDA, the content of Hyp, the serum content of hydroxide free radical, and the serum levels of TGF-β1 and TNF-α in the treatment group were significantly lower than those in radiation group at 24 th week, (t lung coefficient = 1.60, t MDA = 7.06, t Hyp = 17.44, t TGF-β1 = 16.67, t TNF-α = 14.03, P < 0.05), while slightly higher than those in control group. The activity of SOD was significantly higher in the treatment group than that in radiation group (t = 60.81, P < 0.05), while lower than those in control group and drug group. There were no

  11. Radiation-Induced Topological Disorder in Irradiated Network Structures

    International Nuclear Information System (INIS)

    Hobbs, Linn W.

    2002-12-01

    This report summarizes results of a research program investigating the fundamental principles underlying the phenomenon of topological disordering in a radiation environment. This phenomenon is known popularly as amorphization, but is more formally described as a process of radiation-induced structural arrangement that leads in crystals to loss of long-range translational and orientational correlations and in glasses to analogous alteration of connectivity topologies. The program focus has been on a set compound ceramic solids with directed bonding exhibiting structures that can be described as networks. Such solids include SiO2, Si3N4, SiC, which are of interest to applications in fusion energy production, nuclear waste storage, and device manufacture involving ion implantation or use in radiation fields. The principal investigative tools comprise a combination of experimental diffraction-based techniques, topological modeling, and molecular-dynamics simulations that have proven a rich source of information in the preceding support period. The results from the present support period fall into three task areas. The first comprises enumeration of the rigidity constraints applying to (1) more complex ceramic structures (such as rutile, corundum, spinel and olivine structures) that exhibit multiply polytopic coordination units or multiple modes of connecting such units, (2) elemental solids (such as graphite, silicon and diamond) for which a correct choice of polytope is necessary to achieve correct representation of the constraints, and (3) compounds (such as spinel and silicon carbide) that exhibit chemical disorder on one or several sublattices. With correct identification of the topological constraints, a unique correlation is shown to exist between constraint and amorphizability which demonstrates that amorphization occurs at a critical constraint loss. The second task involves the application of molecular dynamics (MD) methods to topologically-generated models

  12. Reduction of Radiation-Induced Changes in Biophysical Properties of Erythrocytes

    International Nuclear Information System (INIS)

    El-Marakby, S.M.A.

    2014-01-01

    . The administration of poly-MVA after irradiation alleviated the radiation-induced damage as appeared from the non-significant change in the measured parameters compared to control. It also showed improvement in the observed parameters. The group which received continuous administration, before and after irradiation, showed better results compared to the group which received administration before irradiation only. The present work gives insight on the radio-protective role of poly-MVA and recommends that it can be used as prophylactic as well as mitigator agent on planned and accidental radiation exposure.

  13. Accidental Datura stramonium poisoning in a dog.

    Science.gov (United States)

    Tostes, Raimundo A

    2002-02-01

    Datura stramonium is potentially poisonous to humans and livestock; however, there's little description of clinical and pathological findings in dogs naturally intoxicated. We report an accidental Datura stramonium poisoning in a dog emphasizing the importance of recognizing the classical signs of anticholinergic poisoning.

  14. Duplication of appendix: an accidental finding

    OpenAIRE

    Varshney, Manoranjan; Shahid, Mohammad; Maheshwari, Veena; Mubeen, Aysha; Gaur, Kavita

    2011-01-01

    Duplication of appendix is extremely rare anomaly. The reported incidence is 0.004–0.009%. In most of the cases the finding is accidental. Here the authors are presenting a case of type A duplex appendix in a 25-year male patient.

  15. Carcinoid Tumor in Accidental, Asymptomatic Meckel's Diverticulum ...

    African Journals Online (AJOL)

    Carcinoid Tumor in Accidental, Asymptomatic Meckel's Diverticulum. Z Baranyai, V Jósa, K Merkel, Z Zolnai. Abstract. Although Meckel's diverticulum is the most common congenital gastrointestinal disorder, it is controversial whether asymptomatic diverticula in adults should be respected. The authors report the case of a ...

  16. Radiation-induced emesis: a prospective observational multicenter Italian trial

    International Nuclear Information System (INIS)

    1999-01-01

    Purpose: A prospective observational multicenter trial was carried out to assess the incidence, pattern, and prognostic factors of radiation-induced emesis (RIE), and evaluate the use of antiemetic drugs in radiation oncology clinical practice. Methods and Materials: Fifty-one Italian radiation oncology centers took part in this trial. The accrual lasted 2 consecutive weeks, only patients starting radiotherapy in this period were enrolled. Exclusion criteria were age under 18 years, and concomitant chemotherapy. Evaluation was based on diary cards filled in daily by patients during radiotherapy and 1 week after stopping it. Diary cards recorded the intensity of nausea and any episode of vomiting and retching. Prophylactic and symptomatic antiemetic drug prescriptions were also registered. Results: Nine hundred thirty-four patients entered the trial, and 914 were evaluable. Irradiated sites were: breast in 211 patients, pelvis in 210 patients, head and neck in 136 patients, thorax in 129 patients, brain in 52 patients, upper abdomen in 42 patients, skin and/or extremities in 37 patients, and other sites in 97 patients. Vomiting and nausea occurred in 17.1% and 37.3% of patients, respectively, and 38.7% patients had both vomiting and nausea. At multifactorial analysis, the only patient-related risk factor that was statistically significant was represented by previous experience with cancer chemotherapy. Moreover, two radiotherapy (RT)-related factors were significant risk factors for RIE, the irradiated site and field size. In fact, a statistically significant higher percentage of RIE was registered in upper abdomen RT and RT fields > 400 cm 2 . Although nonstatistically significant, patients receiving RT to the thorax and head and neck presented a higher incidence of RIE. Only a minority (14%) of patients receiving RT were given an antiemetic drug, and the prescriptions were more often symptomatic than prophylactic (9% vs. 5%, respectively). Different compounds and

  17. Controlling radiation induced segregation in austenitic stainless steels

    International Nuclear Information System (INIS)

    Ahmedabadi, Parag M.; Kain, Vivekanand

    2011-01-01

    In-core components of austenitic stainless steels in light water reactors (LWRs) are susceptible to irradiation assisted stress corrosion cracking (IASCC) in high temperature and high pressure oxygenated water at temperature around 300 deg C . Though, the exact mechanism for IASCC is not fully understood, radiation-induced segregation (RIS) is considered to be a part of a complex process that leads to IASCC. Therefore, controlling RIS in austenitic stainless steels may lead to improvement in resistance to IASCC. RIS is non-equilibrium segregation/depletion of alloying elements in austenitic stainless steels at LWR operating temperatures. RIS occurs due to adsorption of point defects at grain boundaries and leads to segregation of Si and P and depletion of Cr at grain boundaries. Thus by controlling point defect flux towards grain boundaries, the extent of RIS at grain boundaries can be controlled. An extensive study was carried out to simulate and control RIS in austenitic stainless steels using proton irradiation at 300 deg C . The primary aim of this study was to reduce point defect flux towards grain boundaries. Various approaches viz. grain boundary engineering, addition of oversized alloying element, residual strain within matrix and presence of fine precipitates within the grains and at grain boundaries were employed to control RIS in austenitic stainless steels. A novel approach involving combination of electrochemical technique followed by atomic force microscopic (AFM) examination has been used to examine the nature and the extent of RIS. Type 304, 316 and 347 stainless steels were irradiated at 300 deg C (in FOTIA and PELLETRON) in the range of 0.2 to 1.0 dpa using proton beam. The results obtained so far have indicated that a small amount of pre-strain within the grains is very effective in reducing the flux of point defects towards grain boundaries and reducing the extent of RIS at grain boundaries. The presence of NbC precipitates within the grains is

  18. Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Keith W.

    1999-09-01

    and increase in scientific use can be maintained for the synchrotron x-ray source. A short summary of the present state of the synchrotron radiation-induced x-ray emission (SRIXE) method is presented here. Basically, SRIXE experiments can include any that depend on the detection. of characteristic x-rays produced by the incident x-ray beam born the synchrotron source as they interact with a sample. Thus, experiments done to measure elemental composition, chemical state, crystal, structure, and other sample parameters can be considered in a discussion of SRIXE. It is also clear that the experimentalist may well wish to use a variety of complementary techniques for study of a given sample. For this reason, discussion of computed microtomography (CMT) and x-ray diffraction is included here. It is hoped that this present discussion will serve as a succinct introduction to the basic ideas of SRIXE for those not working in the field and possibly help to stimulate new types of work by those starting in the field as well as by experienced practitioners of the art. The topics covered include short descriptions of (1) the properties of synchrotron radiation, (2) a description of facilities used for its production, (3) collimated microprobe, (4) focused microprobes, (5) continuum and monoenergetic excitation, (6) detection limits, (7) quantitation, (8) applications of SRIXE, (9) computed microtomography (CMT), and (10)chemical speciation using x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS). An effort has been made to cite a wide variety of work from different laboratories to show the vital nature of the field.

  19. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, M.K., E-mail: here.praveen@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Shyama, S.K., E-mail: skshyama@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Sonaye, B.S. [Department of Radiation Oncology, Goa Medical College, Goa (India); Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A. [Department of Zoology, Goa University, Goa 403206 (India); Chaubey, R.C. [Radiation Biology and Health Science Division, Bhabha Atomic Research Centre, Mumbai (India)

    2014-05-01

    Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

  20. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

    International Nuclear Information System (INIS)

    Praveen Kumar, M.K.; Shyama, S.K.; Sonaye, B.S.; Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A.; Chaubey, R.C.

    2014-01-01

    Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

  1. Radiation-induced cytogenetic and hematologic effects on aquatic biota within the Chernobyl exclusion zone

    Energy Technology Data Exchange (ETDEWEB)

    Gudkov, Dmitri I.; Shevtsova, Natalia L.; Pomortseva, Natalia A.; Kaglyan, Alexander Ye. [Institute of Hydrobiology, Geroyev Stalingrada Ave. 12, UA-04210 Kiev (Ukraine); Dzyubenko, Elena V. [G. Skovoroda Pereyaslav-Khmelnitsk State Teacher Training University, Sukhomlinskogo Str. 30, UA-08401 Pereyaslav-Khmelnitsk (Ukraine); Rodionova, Natalia K. [R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, Vasilkovskaya Str. 45, UA-04073 Kiev (Ukraine); Nazarov, Alexander B. [Chernobyl Specialized Enterprise, Radyanska Str. 70, UA-07270 Chernobyl (Ukraine)

    2014-07-01

    water bodies within the ChEZ repeatedly exceeds the level of spontaneous mutagenesis, inherent to the aquatic species (2.0-2.5%) and can be display of radiation-induced genetic instability. In fish dwelling in lakes of the ChEZ a considerable qualitative and quantitative changes in hematopoietic system were registered. In water bodies with high level of radioactive contamination the content of leucocytes in blood of fish was substantially below than their level in fish of the control reservoirs. At that the total amount of thrombocytes in fish from contaminated lakes was higher than control indexes. In blood of the perch from Glubokoye Lake the decreased content of oval forms of thrombocytes was determined. The erythrocytes of the crucian carp and perch from Glubokoye Lake were the most susceptible to pathological changes of both nucleus and cell wall. The total amount of cell abnormality in this water body was registered at following level: for the crucian carp 59.5 0/00, and for the perch 22.6 0/00, that considerably exceeds the indexes of violations for fish from control reservoirs (1.9-4.1 0/00). Among the studied fish of the ChEZ we have not detected individuals without cellular pathologies in peripheral blood. (authors)

  2. Late radiation-induced heart disease after radiotherapy. Clinical importance, radiobiological mechanisms and strategies of prevention

    International Nuclear Information System (INIS)

    Andratschke, Nicolaus; Maurer, Jean; Molls, Michael; Trott, Klaus-Ruediger

    2011-01-01

    The clinical importance of radiation-induced heart disease, in particular in post-operative radiotherapy of breast cancer patients, has been recognised only recently. There is general agreement, that a co-ordinated research effort would be needed to explore all the potential strategies of how to reduce the late risk of radiation-induced heart disease in radiotherapy. This approach would be based, on one hand, on a comprehensive understanding of the radiobiological mechanisms of radiation-induced heart disease after radiotherapy which would require large-scale long-term animal experiments with high precision local heart irradiation. On the other hand - in close co-operation with mechanistic in vivo research studies - clinical studies in patients need to determine the influence of dose distribution in the heart on the risk of radiation-induced heart disease. The aim of these clinical studies would be to identify the critical structures within the organ which need to be spared and their radiation sensitivity as well as a potential volume and dose effect. The results of the mechanistic studies might also provide concepts of how to modify the gradual progression of radiation damage in the heart by drugs or biological molecules. The results of the studies in patients would need to also incorporate detailed dosimetric and imaging studies in order to develop early indicators of impending radiation-induced heart disease which would be a pre-condition to develop sound criteria for treatment plan optimisation.

  3. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Zhen [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Gan, Ye-Hua, E-mail: kqyehuagan@bjmu.edu.cn [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China)

    2015-05-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.

  4. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

    International Nuclear Information System (INIS)

    Meng, Zhen; Gan, Ye-Hua

    2015-01-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN

  5. Expression of endothelial nitric oxide synthase in acute radiation-induced cerebral edema

    International Nuclear Information System (INIS)

    Liu Baoguo; Zhang Baomin; Chen Xiaohua; Gao Yabing; Wang Dewen

    2000-01-01

    Objective: To study the relation between changes in expression of endothelial nitric oxide synthase (eNOS) in brain vascular endothelial cells and acute radiation-induced cerebral edema after 60 Co gamma knife irradiation with a high dose. Methods: The right caudate nucleus of rats were irradiated with 200 Gy 60 Co gamma knife. the rats were sacrificed within 14 days after irradiation. By a light microscopy, electron microscopy, immunohistochemistry and in situ hybridization, the authors studied the formation and development of acute radiation-induced cerebral edema as well as the expression of eNOS in brain vascular endothelial cells. Results: Acute radiation-induced cerebral edema was observed morphologically 2 hours after irradiation and peaked on day 3 after irradiation. The expression of eNOS in brain vascular endothelial cells markedly increased 2 hours after irradiation, which could be consistently visualized during the acute developmental phase of radiation-induced cerebral edema. Conclusion: The increased expression of eNOS may be related to the formation and development of acute radiation-induced cerebral edema after 60 Co gamma knife irradiation with a high dose

  6. Search for the lowest irradiation dose from literatures on radiation-induced cancer in gastrointestinal tract

    International Nuclear Information System (INIS)

    Yoshizawa, Yasuo; Kusama, Tomoko

    1976-01-01

    A survey of past case reports about radiation-induced cancer in the gastrointestinal tract was carried out with the main object of finding the lowest irradiation dose. Search of the literature published since 1923 revealed 80 cases of radiation-induced large intestine cancer and one case of stomach cancer. The cases of radiation-induced cancer in the large intestine had received radiation for the treatment of non-malignant conditions, fibroma, ovarial cyste, myoma, endometritis and duodenal ulcer. The lowest irradiation dose was estimated at 460 rads. Adenocarcinoma was the histopathological finding in all cases of radiation-induced cancer in the caecum, colon and rectum, and squamous cell carcinoma in the cases of anal cancer. The latent period ranged from 1 to 31 years, with the average of 13.6 years. There were some reports of statistical studies of radiation-induced stomach cancer. Three groups were the subjects of these studies. The first group was composed of atomic bomb survivors, the second of patients who had undergone radiation treatment for ankylosing spondilitis, and the third of duodenal ulcer patients subjected to radiation treatment for the purpose of suppressing gastric acid secretion. These statistical studies showed no significant increase of the incidence of stomach cancer in the irradiated groups. (auth.)

  7. Effects of CTGF Blockade on Attenuation and Reversal of Radiation-Induced Pulmonary Fibrosis.

    Science.gov (United States)

    Bickelhaupt, Sebastian; Erbel, Christian; Timke, Carmen; Wirkner, Ute; Dadrich, Monika; Flechsig, Paul; Tietz, Alexandra; Pföhler, Johanna; Gross, Wolfgang; Peschke, Peter; Hoeltgen, Line; Katus, Hugo A; Gröne, Hermann-Josef; Nicolay, Nils H; Saffrich, Rainer; Debus, Jürgen; Sternlicht, Mark D; Seeley, Todd W; Lipson, Kenneth E; Huber, Peter E

    2017-08-01

    Radiotherapy is a mainstay for the treatment of lung cancer that can induce pneumonitis or pulmonary fibrosis. The matricellular protein connective tissue growth factor (CTGF) is a central mediator of tissue remodeling. A radiation-induced mouse model of pulmonary fibrosis was used to determine if transient administration of a human antibody to CTGF (FG-3019) started at different times before or after 20 Gy thoracic irradiation reduced acute and chronic radiation toxicity. Mice (25 mice/group; 10 mice/group in a confirmation study) were examined by computed tomography, histology, gene expression changes, and for survival. In vitro experiments were performed to directly study the interaction of CTGF blockade and radiation. All statistical tests were two-sided. Administration of FG-3019 prevented (∼50%-80%) or reversed (∼50%) lung remodeling, improved lung function, improved mouse health, and rescued mice from lethal irradiation ( P radiation-induced gene expression changes, and reduced myofibroblast abundance and Osteopontin expression. These results indicate that blocking CTGF attenuates radiation-induced pulmonary remodeling and can reverse the process after initiation. CTGF has a central role in radiation-induced fibrogenesis, and FG-3019 may benefit patients with radiation-induced pulmonary fibrosis or patients with other forms or origin of chronic fibrotic diseases. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  8. Late radiation-induced heart disease after radiotherapy. Clinical importance, radiobiological mechanisms and strategies of prevention.

    Science.gov (United States)

    Andratschke, Nicolaus; Maurer, Jean; Molls, Michael; Trott, Klaus-Rüdiger

    2011-08-01

    The clinical importance of radiation-induced heart disease, in particular in post-operative radiotherapy of breast cancer patients, has been recognised only recently. There is general agreement, that a co-ordinated research effort would be needed to explore all the potential strategies of how to reduce the late risk of radiation-induced heart disease in radiotherapy. This approach would be based, on one hand, on a comprehensive understanding of the radiobiological mechanisms of radiation-induced heart disease after radiotherapy which would require large-scale long-term animal experiments with high precision local heart irradiation. On the other hand - in close co-operation with mechanistic in vivo research studies - clinical studies in patients need to determine the influence of dose distribution in the heart on the risk of radiation-induced heart disease. The aim of these clinical studies would be to identify the critical structures within the organ which need to be spared and their radiation sensitivity as well as a potential volume and dose effect. The results of the mechanistic studies might also provide concepts of how to modify the gradual progression of radiation damage in the heart by drugs or biological molecules. The results of the studies in patients would need to also incorporate detailed dosimetric and imaging studies in order to develop early indicators of impending radiation-induced heart disease which would be a pre-condition to develop sound criteria for treatment plan optimisation. Copyright © 2010. Published by Elsevier Ireland Ltd.

  9. Effect of ionizing radiation on hematopoietic stem cells and progenitor cells: Role of apoptosis and potential therapeutic significance of anti-apoptotic treatments; Effet des rayonnements ionisants sur les cellules souches et progeniteurs hematopoietiques : place de l'apoptose et interet therapeutique potentiel des traitements antiapoptotiques

    Energy Technology Data Exchange (ETDEWEB)

    Drouet, M.; Mourcin, F.; Grenier, N.; Mayol, J.F.; Leroux, V. [Unite de Radiohematologie experimentale, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France); Sotto, J.J. [Inst. Albert Bonniot, La Tronche (France); Herodin, F. [Unite de Radiohematologie experimentale, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France)

    2002-07-01

    Bone marrow aplasia observed following ionizing radiation exposure (Total Body Irradiation; gamma dose range: 2-10 Gy) is a result, in particular, of the radiation-induced (RI) apoptosis in hematopoietic stem and progenitor cells (HSPC). We have previously shown in a baboon model of mobilized peripheral blood CD34{sup +} cell irradiation in vitro that RI apoptosis in HSPC was an early event, mostly occurring within the first 24 hours, which involves the CD95 Fas pathway. Apoptosis may be significantly reduced with a combination of 4 cytokines (4F): Stem Cell Factor (SCF), FLT-3 Ligand (FL), thrombopoietin (TPO), and interleukin-3 (IL-3), each at 50 ng{center_dot}mL{sup -1} (15% survival versus <3% untreated cells, 24 h post-irradiation at 2.5 Gy). In this study we show that addition of TNF-{alpha}(800 IU/ml) induces an increase in 4F efficacy in terms of cell survival 24 h after incubation (26% survival after 24 h irradiation exposure at 2.5 Gy) and amplification (k) of CD34{sup +} cells after 6 days in a serum free culture medium (SFM) (k{sub CD34{sup +}} = 4.3 and 6.3 respectively for 4F and successive 4F + TNF-{alpha}/4F treatments). In addition, the 4F combination allows culture on pre-established allogenic irradiated stromal cells in vitro at 4 Gy (k{sub CD34{sup +}} = 4.5). Overall this study suggests (i) the potential therapeutic interest for an early administration of anti-apoptotic cytokines with or without hematopoiesis inhibitors (emergency cytokine therapy) and (ii) the feasibility in the accidentally irradiated individual, of autologous cell therapy based on ex vivo expansion in order to perform autograft of residual HSPC collected after the accident. (author)

  10. The accidental exposure to ionizing radiations

    International Nuclear Information System (INIS)

    2001-01-01

    This article is divided in three parts, the first one gives the radioactivity sources, the doses and the effects, the second part is devoted to the medical exposures, the third part concerns the accidents and the biological effects of an irradiation the different syndromes ( the acute whole-body irradiation syndrome, the localized irradiation syndrome, the inflammatory syndrome, hematopoietic syndrome,neuro-vascular syndrome) are detailed. (N.C.)

  11. Amelioration of ionizing radiation induced lipid peroxidation in mouse liver by Moringa oleifera Lam. leaf extract

    International Nuclear Information System (INIS)

    Sinha, Mahuya; Das, Dipesh Kr; Dey, Sanjit; Datta, Sanjukta; Ghosh, Santinath

    2012-01-01

    Protective effect of Moringa oleifera leaf extract (MoLE) against radiation-induced lipid peroxidation has been investigated. Swiss albino mice, selected from an inbred colony, were administered with MoLE (300 mg/kg body wt) for 15 days before exposing to a single dose of 5 Gy 60 Co-gamma radiation. After treatments, animals were necropsied at different post irradiation intervals (days 1, 7 and 15) and hepatic lipid peroxidation and reduced glutathione (GSH) contents were estimated to observe the relative changes due to irradiation and its possible amelioration by MoLE. It was observed that, MoLE treatment restored GSH in liver and prevented radiation induced augmentation in hepatic lipid peroxidation. Phytochemical analysis showed that MoLE possess various phytochemicals such as ascorbic acid, phenolics (catechin, epicatechin, ferulic acid, ellagic acid, myricetin) etc., which may play the key role in prevention of hepatic lipid peroxidation by scavenging radiation induced free radicals. (author)

  12. Validation of genetic predictors of late radiation-induced morbidity in prostate cancer patients

    DEFF Research Database (Denmark)

    Schack, Line M H; Petersen, Stine E; Nielsen, Steffen

    2017-01-01

    INTRODUCTION: Normal tissue morbidity sets the dose limit for radiotherapy (RT) in cancer treatment and has importance for quality of life for cancer survivors. A previous study of prostate cancer patients treated with RT generated clinical data for radiation-induced morbidity measured by anorectal...... physiological methods and validated questionnaires. Other studies have identified genetic predictors associated with late radiation-induced morbidity outcome. We have expanded biobank material aiming to validate single nucleotide polymorphisms (SNPs) and a gene expression classifier with endpoints on patient......-reported outcomes and biomechanical properties of the anorectum from our cohort matching originally published endpoints. MATERIALS AND METHODS: The present cohort of prostate cancer patients was treated with RT curative intent in 1999-2007. Nine SNPs associated with late radiation-induced morbidity were tested...

  13. Protective Effect of Curcumin on γ - radiation Induced Chromosome Aberrations in Human Blood Lymphocytes

    International Nuclear Information System (INIS)

    AlSuhaibani, E.S

    2008-01-01

    The present work is aimed at evaluating the radioprotective effect of curcumin on γ radiation induced genetic toxicity. The DNA damage was analyzed by the frequencies of chromosome aberrations assay. Human lymphocytes were treated in vitro with 5.0 γg/ml of curcumin for 30 min at 37 degree C then exposed to 1, 2 and 4 Gy gamma-radiation. The lymphocytes which were pre-treated with curcumin exhibited a significant decrease in the frequency of chromosome aberration at 1 and 2 Gy radiation-induced chromosome damage as compared with the irradiated cells which did not receive the curcumin pretreatment. Thus, pretreatment with curcumin gives protection to lymphocytes against γ-radiation induced chromosome aberration at certain doses. (author)

  14. The genetics of radiation-induced and sporadic osteosarcoma: a unifying theory?

    International Nuclear Information System (INIS)

    Rosemann, Michael; Kuosaite, Virginija; Nathrath, Michaela; Atkinson, Michael J.

    2002-01-01

    Cancer is a disease of the genome, with the neoplastic phenotype being passed from one cell generation to the other. Radiation-induced cancer has often been considered to represent a unique entity amongst neoplasia, with the energy deposition being held responsible for both direct (gene mutations) and indirect (bystander effects, induced instability etc) alterations to the cellular genome. However, radiogenic tumours in man and experimental animals appear to be physiologically and genetically indistinguishable from their sporadic counterparts, suggesting that the aetiologies of these two tumour types are in fact closely related. We have conducted a general screen of the genetic alterations in radiation-induced mouse osteosarcoma, a tumour that is histopathologically indistinguishable from human sporadic osteosarcoma. Comparison of the two tumour types indicates the existence of a common set of genetic changes, providing additional evidence to support the concept that the molecular pathology of radiation-induced malignancy is no different to that of sporadic cancers. (author)

  15. Mint oil (Mentha spicata Linn.) offers behavioral radioprotection: a radiation-induced conditioned taste aversion study.

    Science.gov (United States)

    Haksar, A; Sharma, A; Chawla, R; Kumar, Raj; Lahiri, S S; Islam, F; Arora, M P; Sharma, R K; Tripathi, R P; Arora, Rajesh

    2009-02-01

    Mentha spicata Linn. (mint), a herb well known for its gastroprotective properties in the traditional system of medicine has been shown to protect against radiation-induced lethality, and recently its constituents have been found to possess calcium channel antagonizing properties. The present study examined the behavioral radioprotective efficacy of mint oil (obtained from Mentha spicata), particularly in mitigating radiation-induced conditioned taste aversion (CTA), which has been proposed as a behavioral endpoint that is mediated by the toxic effects of gamma radiation on peripheral systems, primarily the gastrointestinal system in the Sprague-Dawley rat model. Intraperitoneal administration of Mentha spicata oil 10% (v/v), 1 h before 2 Gy gamma radiation, was found to render significant radioprotection against CTA (p Mentha spicata can be effectively utilized in preventing radiation-induced behavioral changes. Copyright (c) 2008 John Wiley & Sons, Ltd.

  16. Comparative study of radiation-induced magnetoresistance oscillations in MBE material from different sources

    Science.gov (United States)

    Mani, Ramesh; Wegscheider, Werner; Umansky, Vladimir

    2009-11-01

    Transport studies of GaAs/AlGaAs electron systems have shown microwave- and terahertz- radiation-induced, large amplitude, periodic-in-the-inverse-magnetic-field, magnetoresistance oscillations that saturate into novel radiation-induced zero- resistance states (RIZRS) at the lowest temperatures.[1] The origin of these RIZRS remains an open topic for further experimental investigation, as does the dependence of these phenomena on the impurity configuration and the material quality. It remains to be understood if similar material prepared in different laboratories yield a similar response. In addressing this issue, we examine here the radiation-induced magnetoresistance oscillations in GaAs/AlGaAs material prepared by W. Wegscheider and co-workers, and compare the results to our own previous results obtained on specimens prepared by V. Umansky and co-workers. [4pt] [1] R. G. Mani, W. B. Johnson, V. Umansky, V. Narayanamurti, and K. Ploog, Phys. Rev. B 79, 205320 (2009).

  17. RhoA GTPase regulates radiation-induced alterations in endothelial cell adhesion and migration

    International Nuclear Information System (INIS)

    Rousseau, Matthieu; Gaugler, Marie-Hélène; Rodallec, Audrey; Bonnaud, Stéphanie; Paris, François; Corre, Isabelle

    2011-01-01

    Highlights: ► We explore the role of RhoA in endothelial cell response to ionizing radiation. ► RhoA is rapidly activated by single high-dose of radiation. ► Radiation leads to RhoA/ROCK-dependent actin cytoskeleton remodeling. ► Radiation-induced apoptosis does not require the RhoA/ROCK pathway. ► Radiation-induced alteration of endothelial adhesion and migration requires RhoA/ROCK. -- Abstract: Endothelial cells of the microvasculature are major target of ionizing radiation, responsible of the radiation-induced vascular early dysfunctions. Molecular signaling pathways involved in endothelial responses to ionizing radiation, despite being increasingly investigated, still need precise characterization. Small GTPase RhoA and its effector ROCK are crucial signaling molecules involved in many endothelial cellular functions. Recent studies identified implication of RhoA/ROCK in radiation-induced increase in endothelial permeability but other endothelial functions altered by radiation might also require RhoA proteins. Human microvascular endothelial cells HMEC-1, either treated with Y-27632 (inhibitor of ROCK) or invalidated for RhoA by RNA interference were exposed to 15 Gy. We showed a rapid radiation-induced activation of RhoA, leading to a deep reorganisation of actin cytoskeleton with rapid formation of stress fibers. Endothelial early apoptosis induced by ionizing radiation was not affected by Y-27632 pre-treatment or RhoA depletion. Endothelial adhesion to fibronectin and formation of focal adhesions increased in response to radiation in a RhoA/ROCK-dependent manner. Consistent with its pro-adhesive role, ionizing radiation also decreased endothelial cells migration and RhoA was required for this inhibition. These results highlight the role of RhoA GTPase in ionizing radiation-induced deregulation of essential endothelial functions linked to actin cytoskeleton.

  18. 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

  19. Study on radiation-induced polymerization of vinyl monomers adsorbed on inorganic substances. II. Radiation-induced polymerization of methyl methacrylate adsorbed on several inorganic substances

    International Nuclear Information System (INIS)

    Fukano, K.; Kageyama, E.

    1975-01-01

    The radiation-induced polymerization of methyl methacrylate (MMA) adsorbed on such inorganic substances as silica gel, white carbon, silicic acid anhydride, zeolite, and activated alumina was carried out to compare with the case of styrene. The rate of radiation-induced polymerization adsorbed on inorganic substances was high compared with that of radiation-induced bulk state polymerization, as was the case with styrene. Inorganic substrates which contain aluminum as a component element are more likely to be grafted than those which consist of SiO 2 alone, as with styrene. The molecular weight distribution of unextractable polymer and extractable polymer differs, depending on the type of inorganic substance. Experiments by a preirradiation method were carried out in case of silica gel, white carbon, and silicic acid anhydride. GPC spectra of the polymer obtained were different from those of polymer formed by the simultaneous irradiation method. It appears that all the unextractable polymer is grafted to the inorganic surface with chemical bond

  20. Management of accidental swallowing in implant dentistry.

    Science.gov (United States)

    Souza, Francisley Ávila; Statkievicz, Cristian; Guilhem Rosa, Ana Laura; da Silveira Bossi, Fabrício

    2015-08-01

    This report describes a protocol for managing the accidental swallowing of dental instruments in implant dentistry, illustrated by a patient who accidentally swallowed a hexagonal wrench. The first step was to refer the patient to the medical emergency hospital service for radiographic and clinical evaluation. The hexagonal wrench was located in the stomach and was immediately removed with an endoscopic procedure. The gastric mucosa was sampled via biopsy and the sample submitted to the urease test, which was positive for Helicobacter pylori. Triple treatment was instituted for gastritis caused by H pylori to avoid exposing the patient to unnecessary risk. Removal of a foreign body by means of an endoscopic procedure constitutes a safe and effective treatment. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  1. Spectral and kinetic analysis of radiation induced optical attenuation in silica: towards intrinsic fibre optic dosimetry?

    International Nuclear Information System (INIS)

    Borgermans, P.

    2002-01-01

    The document is an abstract of a PhD thesis. The PhD work concerns the detailed investigation of the behaviour of optical fibres in radiation fields such as is the case for various nuclear and space application,s. The core of the work concerns the spectral and kinetic analysis of the radiation induced optical attenuation. Models describing underlying physical phenomena, both for the spectral and the time dimensions, have been developed. The potential of silica optical fibre waveguides for intrinsic dosimetry has been assessed by employing specific properties of radiation induced defects in the silica waveguide material

  2. Radiation induced myxoma of superior vena cava origin presenting as a right atrial mass.

    Science.gov (United States)

    Sabzi, F; Faraji, R

    2014-01-01

    Myxomas are the most common benign cardiac tumors. Myxomas are more common in the left heart chamber than the right side chamber. An extracardiac origin presenting as a right atrial mass is very rare. Right-sided tumors are considerably less common than left-sided tumors, and however myxoma of great vessels origin presenting as right atrial masses are rare but radiation induced villous myxoma in superior vena cava (SVC) is exceedingly rare tumor. A case of radiation induced myxoma originating in a previously undescribed location and presenting as a right atrial mass is reported.

  3. Studies on protective effects of superoxide dismutase on radiation induced-chromosomal aberrations

    International Nuclear Information System (INIS)

    Zheng Siying; Jiang Jiagui; Lin Xingcheng

    1987-09-01

    This study demonstrates that radiation induced-chromosomal aberrations are not only due to the direct effect of radiation h it , but the indirect effect of free radical as well. Therefore, chromosome damage induced by radiation may be reduced by adding exogenous SOD into the radiation exposed lymphocyte culture to eliminate the superoxide free radical which damages DNA. On the other hand, however, the radiosensitivity of lymphocytes can be raised by adding SOD inhibitor (DDC) into the lymphocyte culture, which makes radiation induced-chromosomal damages more severely

  4. Growth hormone used to control intractable bleeding caused by radiation-induced gastritis.

    Science.gov (United States)

    Zhang, Liang; Xia, Wen-Jie; Zhang, Zheng-Sen; Lu, Xin-Liang

    2015-08-21

    Intractable bleeding caused by radiation-induced gastritis is rare. We describe a 69-year-old man with intractable hemorrhagic gastritis induced by postoperative radiotherapy for the treatment of esophageal carcinoma. Although anti-secretory therapy with or without octreotide was initiated for hemostasis over three months, melena still occurred off and on, and the patient required blood transfusions to maintain stable hemoglobin. Finally growth hormone was used in the treatment of hemorrhage for two weeks, and hemostasis was successfully achieved. This is the first report that growth hormone has been used to control intractable bleeding caused by radiation-induced gastritis.

  5. Pathophysiology of Radiation-Induced Dysphagia in Head and Neck Cancer.

    Science.gov (United States)

    King, Suzanne N; Dunlap, Neal E; Tennant, Paul A; Pitts, Teresa

    2016-06-01

    Oncologic treatments, such as curative radiotherapy and chemoradiation, for head and neck cancer can cause long-term swallowing impairments (dysphagia) that negatively impact quality of life. Radiation-induced dysphagia comprised a broad spectrum of structural, mechanical, and neurologic deficits. An understanding of the biomolecular effects of radiation on the time course of wound healing and underlying morphological tissue responses that precede radiation damage will improve options available for dysphagia treatment. The goal of this review is to discuss the pathophysiology of radiation-induced injury and elucidate areas that need further exploration.

  6. Detection of radiation-induced hydrocarbons in baked sponge cake prepared with irradiated liquid egg

    International Nuclear Information System (INIS)

    Schulzki, G.; Spiegelberg, A.; Boegl, K.W.; Schreiber, G.A.

    1995-01-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg. (Author)

  7. The radiation induced colour centers in the NaBi(WO4)2 crystal

    International Nuclear Information System (INIS)

    Shi Hongsheng; Qin Laishun; Chai Wenxiang; Shu Kangying

    2009-01-01

    The radiation induced colour centers in the NaBi(WO 4 ) 2 crystals are investigated. The NBW crystals are irradiated by the Co 60 . The radiation doses are respectively the 10 4 , 10 5 and 10 6 rad and the corresponding dose rate respectively the 40, 2000 and 7000 rad/h. The maximum absorption wavelength of the radiation induced colour centers are identified at 460-470 nm. The mechanism of the formation of the colour centers is discussed. It is assumed that those colour centers are the F colour centers.

  8. Radiation-induced apoptosis in different pH environments in vitro

    International Nuclear Information System (INIS)

    Lee, Hyung-Sik; Park, Heon J.; Lyons, John C.; Griffin, Robert J.; Auger, Elizabeth A.; Song, Chang W.

    1997-01-01

    Purpose: The effect of environmental pH on the radiation-induced apoptosis in tumor cells in vitro was investigated. Methods and Materials: Mammary adenocarcinoma cells of A/J mice (SCK cells) were irradiated with γ-rays using a 137 Cs irradiator and incubated in media of different pHs. After incubation at 37 deg. C for 24-120 h the extent of apoptosis was determined using agarose gel electrophoresis, TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining, flow cytometry, and release of 3 H from 3 H-thymidine labeled cells. The clonogenicity of the cells irradiated in different pH medium was determined, and the progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Results: Irradiation with 2-12 Gy of γ-rays induced apoptosis in SCK cells in pH 7.5 medium within 48 h as judged from the results of four different assays mentioned. Radiation-induced apoptosis declined as the medium pH was lowered from 7.5 to 6.4. Specifically, the radiation-induced degradation of DNA including the early DNA breaks, as determined with the TUNEL method, progressively declined as the medium pH was lowered so that little DNA fragmentation occurred 48 h after irradiation with 12 Gy in pH 6.6 medium. When the cells were irradiated and incubated for 48 h in pH 6.6 medium and the medium was replaced with pH 7.5 medium, DNA fragmentation promptly occurred. DNA fragmentation also occurred even in pH 6.6 medium when the cells were irradiated and maintained in pH 7.5 medium for 8 h or longer post-irradiation before incubation in pH 6.6 medium. The radiation-induced G 2 arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. Conclusion: Radiation-induced apoptosis in SCK cells in vitro is reversibly suppressed in an acidic environment. Taking the results of four different assays together, it was concluded that early step(s) in the apoptotic pathway, probably the DNA break or upstream of DNA break, is

  9. Decision support tool for accidental pollution management.

    Science.gov (United States)

    Ciolofan, Sorin N; Draghia, Aurelian; Drobot, Radu; Mocanu, Mariana; Cristea, Valentin

    2018-03-01

    Accidental river pollution can cause damage to the environment, put at risk the health of people that use the water for domestic purposes, and, not lastly, compromise dependent economic activities (e.g., agriculture). The reduction of the concentration of pollutant on any river following an accidental pollution can be achieved using dilution, by opening for certain duration the bottom gates of the reservoirs placed on the river's tributaries and releasing a significant volume of clean water in the main river. The hydraulic simulation and the pollutant transport are executed, firstly considering there is no dilution and secondly for the dilution scenario (bottom gates of the reservoirs open). A database was created, containing the results of simulations of pollutant transport for various values of the pollution characteristics in both diluted/undiluted scenarios. The database served for the implementation of a web decision support tool that presents an intuitive and easy to use GUI that allows the user to input details of the accidental pollution. Straightforward actions to be taken are presented to the end-user (e.g., "Open the bottom gates of the reservoir X at time T1 and close it at time T2") and synchronized charts show the effect of the dilution in respect to the concentration of pollutant at certain locations on the river. Using the described approach, a reduction of pollutant concentration in the river with up to 90% can be obtained.

  10. Effects of ionizing radiation on the hematopoietic niche and treatment of acute radiation syndrome by gene therapy in highly-irradiated monkeys

    International Nuclear Information System (INIS)

    Garrigou, Ph.

    2011-01-01

    The hematopoietic stem cell niche represents a complex radiosensitive compartment whose protection is required for recovery from radiation-induced myelosuppression. We initially studied RI effects on endothelial and mesenchymal progenitors by an evaluating radiosensitivity and cell death. Then, we have proposed a new gene therapy strategy based on local and short term secretion of Sonic hedgehog morphogen to favour vascular niche repair and to stimulate residual hematopoietic stem and progenitor cells. We investigated the hematopoietic response of 8-Gy gamma irradiated monkeys to a single intra-osseous injection of xenogeneic multipotent mesenchymal stem cells transduced with a Shh pIRES2 plasmid. Thrombocytopenia and neutropenia duration were significantly reduced in grafted animals and clonogenics normalized from day 42. Areas under the curve of PLTs and ANCs between day 0 and day 30 were significantly higher in treated animals than in controls. Grafting Matrigel TM colonized or not with ASC in immunocompromised mice demonstrated a notable pro-angiogenic activity for Shh-ASC. Long term follow up (180-300 days) confirmed a durable recovery in the four grafted monkeys. Globally this study suggests that grafting Shh-multipotent stem cells may represent a new strategy to cure radiation-induced niche damage. (author)

  11. Thrombopoietin and hematopoietic stem cells

    Science.gov (United States)

    de Graaf, Carolyn A

    2011-01-01

    Thrombopoietin (TPO) is the cytokine that is chiefly responsible for megakaryocyte production but increasingly attention has turned to its role in maintaining hematopoietic stem cells (HSCs). HSCs are required to initiate the production of all mature hematopoietic cells, but this differentiation needs to be balanced against self-renewal and quiescence to maintain the stem cell pool throughout life. TPO has been shown to support HSC quiescence during adult hematopoiesis, with the loss of TPO signaling associated with bone marrow failure and thrombocytopenia. Recent studies have shown that constitutive activation mutations in Mpl contribute to myeloproliferative disease. In this review, we will discuss TPO signaling pathways, regulation of TPO levels and the role of TPO in normal hematopoiesis and during myeloproliferative disease. PMID:21478671

  12. A Nonhuman Primate Model of Human Radiation-Induced Venocclusive Liver Disease and Hepatocyte Injury

    Energy Technology Data Exchange (ETDEWEB)

    Yannam, Govardhana Rao [Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska (United States); Han, Bing [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi' an Jiaotong University, Xi' an, Shaanxi (China); Setoyama, Kentaro [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Yamamoto, Toshiyuki [Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska (United States); Ito, Ryotaro; Brooks, Jenna M. [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Guzman-Lepe, Jorge [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Department of Pathology, Children' s Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); Galambos, Csaba [Department of Pathology, Children' s Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); Fong, Jason V. [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Deutsch, Melvin; Quader, Mubina A. [Department of Radiation Oncology, Children' s Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); Yamanouchi, Kosho [Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, New York (United States); Marion Bessin Liver Research Center, Albert Einstein College of Medicine, Bronx, New York (United States); Kabarriti, Rafi; Mehta, Keyur [Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, New York (United States); Soto-Gutierrez, Alejandro [Department of Pathology, Children' s Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); and others

    2014-02-01

    Background: Human liver has an unusual sensitivity to radiation that limits its use in cancer therapy or in preconditioning for hepatocyte transplantation. Because the characteristic veno-occlusive lesions of radiation-induced liver disease do not occur in rodents, there has been no experimental model to investigate the limits of safe radiation therapy or explore the pathogenesis of hepatic veno-occlusive disease. Methods and Materials: We performed a dose-escalation study in a primate, the cynomolgus monkey, using hypofractionated stereotactic body radiotherapy in 13 animals. Results: At doses ≥40 Gy, animals developed a systemic syndrome resembling human radiation-induced liver disease, consisting of decreased albumin, elevated alkaline phosphatase, loss of appetite, ascites, and normal bilirubin. Higher radiation doses were lethal, causing severe disease that required euthanasia approximately 10 weeks after radiation. Even at lower doses in which radiation-induced liver disease was mild or nonexistent, latent and significant injury to hepatocytes was demonstrated by asialoglycoprotein-mediated functional imaging. These monkeys developed hepatic failure with encephalopathy when they received parenteral nutrition containing high concentrations of glucose. Histologically, livers showed central obstruction via an unusual intimal swelling that progressed to central fibrosis. Conclusions: The cynomolgus monkey, as the first animal model of human veno-occlusive radiation-induced liver disease, provides a resource for characterizing the early changes and pathogenesis of venocclusion, for establishing nonlethal therapeutic dosages, and for examining experimental therapies to minimize radiation injury.

  13. Role of rosemary leaves extract against radiation-induced hematological and biochemical alterations in mice

    International Nuclear Information System (INIS)

    Acharya, G. S.; Goyal, P. K.

    2008-01-01

    The present paper is a study of the modulatory effect of Rosmarinus officinalis leaves extract on radiation-induced hematological and biochemical changes in Swiss albino mice.The dose reduction factor for the Rosemary extract against gamma rays was calculated 1.53 from LD 50/30 values. The Rosemary extract was administered orally for 5 consecutive days prior to radiation exposure. The hematological and biochemical parameters were assessed from day 1 to 30 post-irradiation intervals. The total erythrocyte count, total leucocytes count, hemoglobin, and hematocrit values in the experimental group were found to be elevated as compared to the control group of mice. Furthermore, the Rosemary extract treatment enhanced reduced glutathione content in the liver and blood against radiation-induced depletion. Treatment with the plant extract brought a significant fall in the lipid peroxidation level, suggesting rosemary's role in protection against radiation-induced membrane and cellular damage. The results from the present study suggest a radio-protective effect of the Rosemary extract against radiation-induced hematological and biochemical alterations in mice. (author)

  14. 3D ultrasound Nakagami imaging for radiation-induced vaginal fibrosis

    Science.gov (United States)

    Yang, Xiaofeng; Rossi, Peter; Shelton, Joseph; Bruner, Debrorah; Tridandapani, Srini; Liu, Tian

    2014-03-01

    Radiation-induced vaginal fibrosis is a debilitating side-effect affecting up to 80% of women receiving radiotherapy for their gynecological (GYN) malignancies. Despite the significant incidence and severity, little research has been conducted to identify the pathophysiologic changes of vaginal toxicity. In a previous study, we have demonstrated that ultrasound Nakagami shape and PDF parameters can be used to quantify radiation-induced vaginal toxicity. These Nakagami parameters are derived from the statistics of ultrasound backscattered signals to capture the physical properties (e.g., arrangement and distribution) of the biological tissues. In this paper, we propose to expand this Nakagami imaging concept from 2D to 3D to fully characterize radiation-induced changes to the vaginal wall within the radiation treatment field. A pilot study with 5 post-radiotherapy GYN patients was conducted using a clinical ultrasound scanner (6 MHz) with a mechanical stepper. A serial of 2D ultrasound images, with radio-frequency (RF) signals, were acquired at 1 mm step size. The 2D Nakagami shape and PDF parameters were calculated from the RF signal envelope with a sliding window, and then 3D Nakagami parameter images were generated from the parallel 2D images. This imaging method may be useful as we try to monitor radiation-induced vaginal injury, and address vaginal toxicities and sexual dysfunction in women after radiotherapy for GYN malignancies.

  15. Using Rouse-Fowler model to describe radiation-induced electrical conductivity of nanocomposite materials

    Science.gov (United States)

    Dyuryagina, N. S.; Yalovets, A. P.

    2017-05-01

    Using the Rouse-Fowler (RF) model this work studies the radiation-induced electrical conductivity of a polymer nanocomposite material with spherical nanoparticles against the intensity and exposure time of gamma-ray, concentration and size of nanoparticles. The research has found the energy distribution of localized statesinduced by nanoparticles. The studies were conducted on polymethylmethacrylate (PMMA) with CdS nanoparticles.

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

    International Nuclear Information System (INIS)

    Gebicka, L.; Metodiewa, D.

    1988-01-01

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

  17. Immobilization of yeast cells with various porous carriers by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Fujimura, Takashi; Kaetsu, Isao

    1982-06-01

    Yeast cells were immobilized by radiation-induced polymerization in twice. Various kinds of porous polymer carriers were prepared by radiation-induced polymerization of glass-forming monomers at a low temperature. Precultured yeast cells were incubated aerobically at 30 0 C with these porous carriers for 24 h. Porous carriers with yeast cells were immersed in low concentration monomer solution. Yeast cells were immobilized by radiation-induced polymerization. The maximum ethanol productivity in immobilized yeast system was around 10 times as much as that in free yeast cell system. High activity of immobilized yeast cells was maintained more than 480 h. The growth of yeast cells in immobilized yeast cells during aerobical incubation was indicated. Immobilized yeast cells thus grown were incubated for fermentation reaction. In this immobilized system, 100% of glucose was converted to ethanol, that is 100% ethanol yield was obtained, within 180 min. In free cell system, only 15% ethanol yield was obtained within 180 min. These results indicates clearly the superiority of immobilized growing cell. Yeast cells were also immobilized with non woven material as carrier by radiation-induced polymerization. The relationship between pore size of non woven material and activity in immobilized yeast cells was made clear. (author)

  18. Radiation-induced rectal cancer originating from a rectocutaneous fistula. Report of a case

    International Nuclear Information System (INIS)

    Yokoyama, Shozo; Takifuji, Katsunari; Arii, Kazuo; Tanaka, Hajime; Matsuda, Kenji; Higashiguchi, Takashi; Yamaue, Hiroki

    2004-01-01

    This report describes a patient with radiation-induced rectal cancer with an unusual history. A 51-year-old man was admitted in 2000 because of ichorrhea of the skin on the left loin. The patient had received irradiation for a suspicious diagnosis of a malignant tumor in the pelvic cavity in 1975. A subcutaneous abscess in the right loin appeared in 1989, and rectocutaneous fistula was noted in 1992. Moreover, radiation-induced rectal cancer developed in 2000. Plain computed tomography and magnetic resonance imaging of the pelvis demonstrated a presacral mass and tumor in the rectum. Finally, we diagnosed the presacral mass to be an abscess attached to the center of the rectal cancer. The rectum was resected by Miles' operation and a colostomy of the sigmoid colon was also performed. Many cases of radiation-induced rectal cancer have been reported. However, this is a rare case of radiation-induced rectal cancer originating from a presacral abscess and rectocutaneous fistula. (author)

  19. Modification of radiation-induced division delay by caffeine analogues and dibutyryl cyclic AMP

    Energy Technology Data Exchange (ETDEWEB)

    Kimler, B.F.; Leeper, D.B.; Snyder, M.H.; Rowley, R.; Schneiderman, M.H. (Thomas Jefferson Univ., Philadelphia, PA (USA). Hospital)

    1982-01-01

    The mitotic selection procedure for cell cycle analysis was utilized to investigate the concentration-dependent modification of x-radiation-induced division delay in Chinese hamster ovary (CHO) cells by methyl xanthines (caffeine, theophylline, and theobromine) and by dibutyryl cyclic AMP. The methyl xanthines (concentrations from 0.5 to 1000 ..mu..g/ml) all reduced radiation-induced division delay with the effect being linear between approximately 100 and 1000 ..mu..g/ml. After doses of 100-300 rad, delay was reduced by 75, 94 or 83 per cent at 1000 ..mu..g/ml for each drug, respectively. However, the addition of dibutyryl cyclic AMP had an opposite effect: radiation-induced delay was increased by the concentration range of 0.3 to 300 ..mu..g/ml. These results indicate that in mammalian cells the control of cell cycle progression and the modification of radiation-induced division delay are not simply related to intracellular levels of cyclic AMP. Rather, there appear to be at least two competing mechanisms which are differentially affected by caffeine analogues or by direct addition of dibutyryl cyclic AMP. The direct effect of caffeine and the methyl xanthines on membrane calcium permeability is considered.

  20. A Nonhuman Primate Model of Human Radiation-Induced Venocclusive Liver Disease and Hepatocyte Injury

    International Nuclear Information System (INIS)

    Yannam, Govardhana Rao; Han, Bing; Setoyama, Kentaro; Yamamoto, Toshiyuki; Ito, Ryotaro; Brooks, Jenna M.; Guzman-Lepe, Jorge; Galambos, Csaba; Fong, Jason V.; Deutsch, Melvin; Quader, Mubina A.; Yamanouchi, Kosho; Kabarriti, Rafi; Mehta, Keyur; Soto-Gutierrez, Alejandro

    2014-01-01

    Background: Human liver has an unusual sensitivity to radiation that limits its use in cancer therapy or in preconditioning for hepatocyte transplantation. Because the characteristic veno-occlusive lesions of radiation-induced liver disease do not occur in rodents, there has been no experimental model to investigate the limits of safe radiation therapy or explore the pathogenesis of hepatic veno-occlusive disease. Methods and Materials: We performed a dose-escalation study in a primate, the cynomolgus monkey, using hypofractionated stereotactic body radiotherapy in 13 animals. Results: At doses ≥40 Gy, animals developed a systemic syndrome resembling human radiation-induced liver disease, consisting of decreased albumin, elevated alkaline phosphatase, loss of appetite, ascites, and normal bilirubin. Higher radiation doses were lethal, causing severe disease that required euthanasia approximately 10 weeks after radiation. Even at lower doses in which radiation-induced liver disease was mild or nonexistent, latent and significant injury to hepatocytes was demonstrated by asialoglycoprotein-mediated functional imaging. These monkeys developed hepatic failure with encephalopathy when they received parenteral nutrition containing high concentrations of glucose. Histologically, livers showed central obstruction via an unusual intimal swelling that progressed to central fibrosis. Conclusions: The cynomolgus monkey, as the first animal model of human veno-occlusive radiation-induced liver disease, provides a resource for characterizing the early changes and pathogenesis of venocclusion, for establishing nonlethal therapeutic dosages, and for examining experimental therapies to minimize radiation injury

  1. On the mechanisms of the radiation-induced degradation of cellulosic substances

    Science.gov (United States)

    Tissot, Chanel; Grdanovska, Slavica; Barkatt, Aaron; Silverman, Joseph; Al-Sheikhly, Mohamad

    2013-03-01

    Much interest has been generated in utilizing ionizing radiation for the production of bio-fuels from cellulosic plant materials. It is well known that exposure of cellulose to ionizing radiation causes significant breakdown of the polysaccharide. Radiation-induced degradation of cellulose may reduce or replace ecologically hazardous chemical steps in addition to reducing the number of processing stages and decreasing energy consumption.

  2. Stem Cell Therapy to Reduce Radiation-Induced Normal Tissue Damage

    NARCIS (Netherlands)

    Coppes, Rob P.; van der Goot, Annemieke; Lombaert, Isabelle M. A.

    Normal tissue damage after radiotherapy is still a major problem in cancer treatment. Stem cell therapy may provide a means to reduce radiation-induced side effects and improve the quality of life of patients. This review discusses the current status in stem cell research with respect to their

  3. Visible light- and radiation-induced alkylation of pyridine ring with alkanoic acid

    International Nuclear Information System (INIS)

    Sugimori, Akira; Yamada, Tetsuo

    1986-01-01

    Quinoline and 4-methylquinoline are efficiently alkylated with alkanoic acid in the presence of iron(III) sulfate upon visible light-irradiation. Iron(III) sulfate not only accelerates the photoreaction but also increases the yield of alkylation. Gamma-irradiation also brings about the alkylation. In the photo- and radiation-induced alkylation with alkanoic acid, alkyl radicals play important roles. (author)

  4. Short-duration exposure to 2.45 GHz microwave radiation induces ...

    African Journals Online (AJOL)

    OBEMBE

    radiation induces DNA damage in Sprague Dawley rat's reproductive ... affect both male and female fertility adversely. ... 4% relative humidity. Exposures were whole body irradiation with the animal at 12 cm from the MW antenna of dimensions 12 x 5 cm. The animals were divided into ten groups of three males and three.

  5. Molecular, Cellular and Functional Effects of Radiation-Induced Brain Injury: A Review.

    Science.gov (United States)

    Balentova, Sona; Adamkov, Marian

    2015-11-24

    Radiation therapy is the most effective non-surgical treatment of primary brain tumors and metastases. Preclinical studies have provided valuable insights into pathogenesis of radiation-induced injury to the central nervous system. Radiation-induced brain injury can damage neuronal, glial and vascular compartments of the brain and may lead to molecular, cellular and functional changes. Given its central role in memory and adult neurogenesis, the majority of studies have focused on the hippocampus. These findings suggested that hippocampal avoidance in cranial radiotherapy prevents radiation-induced cognitive impairment of patients. However, multiple rodent studies have shown that this problem is more complex. As the radiation-induced cognitive impairment reflects hippocampal and non-hippocampal compartments, it is of critical importance to investigate molecular, cellular and functional modifications in various brain regions as well as their integration at clinically relevant doses and schedules. We here provide a literature overview, including our previously published results, in order to support the translation of preclinical findings to clinical practice, and improve the physical and mental status of patients with brain tumors.

  6. Molecular, Cellular and Functional Effects of Radiation-Induced Brain Injury: A Review

    Directory of Open Access Journals (Sweden)

    Sona Balentova

    2015-11-01

    Full Text Available Radiation therapy is the most effective non-surgical treatment of primary brain tumors and metastases. Preclinical studies have provided valuable insights into pathogenesis of radiation-induced injury to the central nervous system. Radiation-induced brain injury can damage neuronal, glial and vascular compartments of the brain and may lead to molecular, cellular and functional changes. Given its central role in memory and adult neurogenesis, the majority of studies have focused on the hippocampus. These findings suggested that hippocampal avoidance in cranial radiotherapy prevents radiation-induced cognitive impairment of patients. However, multiple rodent studies have shown that this problem is more complex. As the radiation-induced cognitive impairment reflects hippocampal and non-hippocampal compartments, it is of critical importance to investigate molecular, cellular and functional modifications in various brain regions as well as their integration at clinically relevant doses and schedules. We here provide a literature overview, including our previously published results, in order to support the translation of preclinical findings to clinical practice, and improve the physical and mental status of patients with brain tumors.

  7. γ-radiation induced corrosion of copper in bentonite-water systems under anaerobic conditions

    Science.gov (United States)

    Karin Norrfors, K.; Björkbacka, Åsa; Kessler, Amanda; Wold, Susanna; Jonsson, Mats

    2018-03-01

    In this work we have experimentally studied the impact of bentonite clay on the process of radiation-induced copper corrosion in anoxic water. The motivation for this is to further develop our understanding of radiation-driven processes occurring in deep geological repositories for spent nuclear fuel where copper canisters containing the spent nuclear fuel will be embedded in compacted bentonite. Experiments on radiation-induced corrosion in the presence and absence of bentonite were performed along with experiments elucidating the impact irradiation on the Cu2+ adsorption capacity of bentonite. The experiments presented in this work show that the presence of bentonite clay has no or very little effect on the magnitude of radiation-induced corrosion of copper in anoxic aqueous systems. The absence of a protective effect similar to that observed for radiation-induced dissolution of UO2 is attributed to differences in the corrosion mechanism. This provides further support for the previously proposed mechanism where the hydroxyl radical is the key radiolytic oxidant responsible for the corrosion of copper. The radiation effect on the bentonite sorption capacity of Cu2+ (reduced capacity) is in line with what has previously been reported for other cations. The reduced cation sorption capacity is partly attributed to a loss of Al-OH sites upon irradiation.

  8. Short and long term radiation induced cardiovascular disease in patients with cancer

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Melgaard; Offersen, Birgitte Vrou; Nielsen, Hanne Melgaard

    2017-01-01

    Radiation-induced cardiovascular disease is well described as a late effect in cancer patients treated with radiation therapy. Advancements in surgery, radiotherapy, and chemotherapy have led to an increasing number of cancer survivors with resultant long-term side effects related to their cancer...

  9. Peptideinduced Emesis in Dogs: Possible Relevance to Radiation-Induced Emesis.

    Science.gov (United States)

    1982-09-01

    accompanied by indications of gastrointestinal activation, including retching, defecation, and often an obvious increase in peristalsis . Several other...IN DOGS: POSSIBLE RELEVANCE TO RADIATION-INDUCED EMESIS INTRODUCTION Emesis is frequently present in a variety of gastrointestinal illnesses resulting...3) demonstrated that the motor act of emesis could be elicited through two separate neuronal pathways. Local gastrointestinal irritation, such as

  10. Prevention and management of radiation-induced dermatitis, mucositis, and xerostomia.

    Science.gov (United States)

    Radvansky, Lauren J; Pace, Makala B; Siddiqui, Asif

    2013-06-15

    Current strategies for preventing and managing radiation-induced dermatitis, mucositis, and xerostomia are reviewed, with an emphasis on pharmacologic interventions. Nearly two thirds of all patients with cancer receive radiation therapy during the course of treatment, frequently resulting in acute skin and mucosal toxicities. The severity of radiotherapy-associated toxicities varies according to multiple treatment- and patient-related factors (e.g., total radiation dose and dose fractionation schedule, volume of organ or tissue irradiated, use of concurrent versus sequential chemotherapy, comorbid conditions, functional performance status). Three major radiation toxicities encountered in clinical practice are (1) radiation dermatitis, typically managed with a variety of topical agents such as water-based moisturizing creams or lotions, topical steroids, antiinflammatory emulsions, and wound dressings, (2) radiation-induced oral mucositis, which can be managed through proper basic oral care practices, appropriate pain management, and the use of medicated mouthwashes and oral rinses and gels, and (3) radiation-induced xerostomia, which can be alleviated with saliva substitutes, moistening agents, and sialagogues. Pharmacists involved in the care of patients receiving radiotherapy can play an important role in optimizing symptom control, educating patients on self-care strategies, and adverse effect monitoring and reporting. Radiation-induced dermatitis, mucositis, and xerostomia can cause significant morbidity and diminished quality of life. Pharmacologic interventions for the prevention and treatment of these toxicities include topical agents for dermatitis; oral products, analgesics, and palifermin for mucositis; and amifostine, saliva substitutes, and pilocarpine for xerostomia.

  11. Stem cells and the repair of radiation-induced salivary gland damage

    NARCIS (Netherlands)

    Coppes, R. P.; Stokman, M. A.

    Hyposalivation underlying xerostomia after radiotherapy is still a major problem in the treatment of head and neck cancer. Stem cell therapy may provide a means to reduce radiation-induced hyposalivation and improve the quality of life of patients. This review discusses the current status in

  12. Base substitutions, frameshifts, and small deletions constitute ionizing radiation-induced point mutations in mammalian cells

    International Nuclear Information System (INIS)

    Grosovsky, A.J.; de Boer, J.G.; de Jong, P.J.; Drobetsky, E.A.; Glickman, B.W.

    1988-01-01

    The relative role of point mutations and large genomic rearrangements in ionizing radiation-induced mutagenesis has been an issue of long-standing interest. Recent studies using Southern blotting analysis permit the partitioning of ionizing radiation-induced mutagenesis in mammalian cells into detectable deletions and major genomic rearrangements and into point mutations. The molecular nature of these point mutations has been left unresolved; they may include base substitutions as well as small deletions, insertions, and frame-shifts below the level of resolution of Southern blotting analysis. In this investigation, we have characterized a collection of ionizing radiation-induced point mutations at the endogenous adenine phosphoribosyltransferase (aprt) locus of Chinese hamster ovary cells at the DNA sequence level. Base substitutions represented approximately equal to 2/3 of the point mutations analyzed. Although the collection of mutants is relatively small, every possible type of base substitution event has been recovered. These mutations are well distributed throughout the coding sequence with only one multiple occurrence. Small deletions represented the remainder of characterized mutants; no insertions have been observed. Sequence-directed mechanisms mediated by direct repeats could account for some of the observed deletions, while others appear to be directly attributable to radiation-induced strand breakage

  13. Application of radiation-induced apoptosis in radiation oncology and radiation protection

    International Nuclear Information System (INIS)

    Crompton, N.E.A.; Emery, G.C.; Ozsahin, M.; Menz, R.; Knesplova, L.; Larsson, B.

    1997-01-01

    A rapid assay of the ability of lymphocytes to respond to radiation-induced damage is presented. Age and genetic dependence of radiation response have been quantified. The assay is sensitive to low doses of radiation. Its ability to assess the cytotoxic response of blood capillaries to radiation has been evaluated. (author)

  14. Search for the lowest irradiation dose from literatures on radiation-induced cancer in uterus

    International Nuclear Information System (INIS)

    Yoshizawa, Yasuo; Kusama, Tomoko

    1975-01-01

    A survey of past case reports on radiation-induced cancer of the uterus was carried out with the main object of finding the lowest irradiation dose. Search of literature published since 1912 revealed 548 cases of radiation-induced cancer of the uterus. All of these cases of radiation-induced cancer had received radiation for the treatment of non-malignant disease. The primary gynecological conditions which were the object of radiation therapy were functional bleeding, endometrial hyperplasia, myoma, endometritis, and polyps. The lowest irradiation dose was estimated at 1000-1450 rad in the case of external X-ray irradiation, and 100 mg.hr for intrauterine radium therapy, which corresponds to 100-1000 rad. It was noted that were more cases of corpus cancer than cervical cancer. Histopathological findings of radiation-induced uterine cancer were carcinoma, sarcoma, and mixed mesodermal tumors. The latent period was distributed in the range of 1 to 40 years, with the average of 10.1 years. (auth.)

  15. A Prospective Cohort Study on Radiation-induced Hypothyroidism : Development of an NTCP Model

    NARCIS (Netherlands)

    Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E. M. C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J. H. M.; van der Laan, Bernard F. A. M.; Wolffenbuttel, Bruce H. R.; Oosting, Sjoukje F.; Schilstra, Cornelis; Langendijk, Johannes A.

    2012-01-01

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively

  16. Radiation-induced hypothyroidism in head and neck cancer patients : A systematic review

    NARCIS (Netherlands)

    Boomsma, Marjolein J.; Bijl, Hendrik P.; Langendijk, Johannes A.

    Purpose: To review literature on the relationship between the dose distribution in the thyroid gland and the incidence of radiation-induced hypothyroidism in adults. Material and Methods: Articles were identified through a search in MEDLINE, EMBASE and the Cochrane Library. Approximately 2449

  17. Radiation-induced conductivity and high-temperature Q changes in quartz resonators

    International Nuclear Information System (INIS)

    Koehler, D.R.

    1981-01-01

    While high temperature electrolysis has proven beneficial as a technique to remove interstitial impurities from quartz, reliable indices to measure the efficacy of such a processing step are still under development. The present work is directed toward providing such an index. Two techniques have been investigated - one involves measurement of the radiation induced conductivity in quartz along the optic axis, and the second involves measurement of high temperature Q changes. Both effects originate when impurity charge compensators are released from their traps, in the first case resulting in ionic conduction and in the second case resulting in increased acoustic losses. Radiation induced conductivity measurements have been carried out with a 200 kV, 14 mA x-ray machine producing 5 rads/s. With electric fields of the order of 10 4 V/cm, the noise level in the current measuring system is equivalent to an ionic current generated by quartz impurities in the 1 ppB range. The accuracy of the high temperature ( 300 to 800 0 K) Q -1 measurement technique will be determined. A number of resonators constructed of quartz material of different impurity contents have been tested and both the radiation induced conductivity and the high temperature Q -1 results compared with earlier radiation induced frequency and resonator resistance changes. 10 figures

  18. Radiation-induced decomposition of the purine bases within DNA and related model compounds

    International Nuclear Information System (INIS)

    Cadet, J.; Berger, M.

    1985-01-01

    This survey focuses on recent developments in the radiation chemistry of purine bases in nucleic acids and related model compounds. Both direct and indirect effects of ionizing radiation are investigated with special emphasis on the structural characterization of the final decomposition products of nucleic acid components. Available assays for monitoring radiation-induced base lesions are critically reviewed. (author)

  19. A Prospective Cohort Study on Radiation-induced Hypothyroidism: Development of an NTCP Model

    Energy Technology Data Exchange (ETDEWEB)

    Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Laan, Bernard F.A.M. van der [Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Oosting, Sjoukje F. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Schilstra, Cornelis [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A., E-mail: j.a.langendijk@umcg.nl [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

    2012-11-01

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively measured during a median follow-up of 2.5 years. Hypothyroidism was defined as elevated serum TSH with decreased or normal free thyroxin (T4). A multivariate logistic regression model with bootstrapping was used to determine the most important prognostic variables for radiation-induced hypothyroidism. Results: Thirty-five patients (33%) developed primary hypothyroidism within 2 years after radiation therapy. An NTCP model based on 2 variables, including the mean thyroid gland dose and the thyroid gland volume, was most predictive for radiation-induced hypothyroidism. NTCP values increased with higher mean thyroid gland dose (odds ratio [OR]: 1.064/Gy) and decreased with higher thyroid gland volume (OR: 0.826/cm{sup 3}). Model performance was good with an area under the curve (AUC) of 0.85. Conclusions: This is the first prospective study resulting in an NTCP model for radiation-induced hypothyroidism. The probability of hypothyroidism rises with increasing dose to the thyroid gland, whereas it reduces with increasing thyroid gland volume.

  20. A Prospective Cohort Study on Radiation-induced Hypothyroidism: Development of an NTCP Model

    International Nuclear Information System (INIS)

    Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M.; Laan, Bernard F.A.M. van der; Wolffenbuttel, Bruce H.R.; Oosting, Sjoukje F.; Schilstra, Cornelis; Langendijk, Johannes A.

    2012-01-01

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively measured during a median follow-up of 2.5 years. Hypothyroidism was defined as elevated serum TSH with decreased or normal free thyroxin (T4). A multivariate logistic regression model with bootstrapping was used to determine the most important prognostic variables for radiation-induced hypothyroidism. Results: Thirty-five patients (33%) developed primary hypothyroidism within 2 years after radiation therapy. An NTCP model based on 2 variables, including the mean thyroid gland dose and the thyroid gland volume, was most predictive for radiation-induced hypothyroidism. NTCP values increased with higher mean thyroid gland dose (odds ratio [OR]: 1.064/Gy) and decreased with higher thyroid gland volume (OR: 0.826/cm 3 ). Model performance was good with an area under the curve (AUC) of 0.85. Conclusions: This is the first prospective study resulting in an NTCP model for radiation-induced hypothyroidism. The probability of hypothyroidism rises with increasing dose to the thyroid gland, whereas it reduces with increasing thyroid gland volume.

  1. Radiation-induced apoptosis varies among individuals and is modified by sex and age.

    Science.gov (United States)

    Applebaum, Mark A; Skol, Andrew D; Bond, Elisabeth E; Overholtzer, Michael; Bond, Gareth L; Onel, Kenan

    2014-10-01

    Although there are considerable data on mechanisms of radiation-induced apoptosis in vitro and in animal models, little is known about functional variation in these pathways in humans. We sought to develop a tractable system to evaluate this. Peripheral blood mononuclear cells were isolated from 90 healthy volunteers, divided into two aliquots, one irradiated with a 5 Gy dose and the other sham-treated (0 Gy), and assessed for damage-induced apoptosis after 24 hours. To investigate reproducibility, 10 individuals spanning the entire radiation-induced apoptotic range were tested three times each, with 3-6 months between replicates. We observed surprising heterogeneity in apoptosis among individuals, ranging from 21-62%. Biological replicates from a single individual, however, were completely concordant, suggesting the variability observed across individuals is not the result of stochastic or short-term effects. We found significantly higher radiation-induced apoptosis in males than in females (Mean: 41.0% vs. 30.7%; p < 3.5 × 10(-7)). Moreover, advancing age was associated with decreasing radiation-induced apoptosis in males (p = 0.01) but not females (p = 0.82). Our results provide evidence that the function of cellular pathways crucial for stress-induced apoptosis varies by sex and could decline with age in humans.

  2. Further characterization of the reverse transcriptase associated with porcine (radiation-induced) retroviruses

    International Nuclear Information System (INIS)

    Frazier, M.E.; Mallavia, L.P.; Hooper, M.J.

    1980-01-01

    Differential centrifugation and affinity chromatography were used to purify the porcine, radiation-induced retrovirus, RNA-dependent DNA polymerase. The purified RDDP was taken differentiated from cellular DNA polymerase γ by its template specificity, chromatographic characteristics, and the optimum reaction conditions required for DNA synthesis

  3. The effectiveness of hyperbaric oxygen therapy (HBOT) in radiation-induced haemorrhagic cystitis.

    Science.gov (United States)

    Chong, Vincent; Rice, Michael

    2016-12-02

    Radiation cystitis is one of the possible complications from pelvic radiotherapy. Hyperbaric oxygen (HBOT) improves tissue oxygenation and healing of scarred tissue. To assess the efficacy of hyperbaric oxygen therapy (HBOT) in the management of radiation-induced haemorrhagic cystitis in patients with urological cancers. This is a retrospective review on all patients with macroscopic haematuria secondary to radiation induced haemorrhagic cystitis who were treated with hyperbaric oxygen therapy (HBOT) between 2009 and 2013. The primary outcome is symptomatic assessment (either complete resolution, partial resolution or no change). A total of 12 patients with radiation-induced cystitis secondary to urological cancer were included in this study with a mean follow-up of 443 days. The mean age was 78 years. Complete resolution of haematuria was seen in six out of 12 patients. Partial response was achieved in two patients where one required two courses of HBOT and one required three courses of HBOT. As a result, the overall improvement of haematuria after HBOT was 67%. A total of four patients had no response to HBOT. Radiation-induced cystitis is a difficult clinical problem to treat. HBOT is not a magic bullet but it may be another alternative treatment option we have at this point in time.

  4. Radiation induced cell loss in rat submandibular gland and its relation to gland function

    NARCIS (Netherlands)

    Zeilstra, LJW; Vissink, A; Konings, AWT; Coppes, RP

    Purpose: To understand early and late radiation-induced loss of function of the submandibular gland, changes in cell number were documented and correlated with data on gland function. Modulation of the radiation effect by sialogogues was used to investigate possible mechanisms of action. Materials

  5. Radiation-induced apoptosis in relation to acute impairment of rat salivary gland function

    NARCIS (Netherlands)

    Paardekooper, GMRM; Cammelli, S; Zeilstra, LJW; Coppes, RP; Konings, AWT

    Purpose: To find an answer to the question: Are the acute radiation effects on salivary gland function, as seen in earlier studies, causally related to radiation-induced apoptosis? Materials and methods: Rat parotid and submandibular glands were X-irradiated with doses up to 25 Gy and morphological

  6. Effect of radiation-induced emission of Schottky defects on the formation of colloids in alkali halides

    NARCIS (Netherlands)

    Dubinko, [No Value; Vainshtein, DI; Den Hartog, HW

    2003-01-01

    Formation of vacancy clusters in irradiated crystals is considered taking into account radiation-induced Schottky defect emission (RSDE) from extended defects. RSDE acts in the opposite direction compared with Frenkel pair production, and it results in the radiation-induced recovery processes. In

  7. Chronic restraint-induced stress has little modifying effect on radiation hematopoietic toxicity in mice

    International Nuclear Information System (INIS)

    Wang, Bing; Tanaka, Kaoru; Katsube, Takanori; Ninomiya, Yasuharu; Vares, Guillaume; Nakajima, Tetsuo; Nenoi, Mitsuru; Liu Qiang; Morita, Akinori

    2015-01-01

    Both radiation and stresses cause detrimental effects on humans. Besides possible health effects resulting directly from radiation exposure, the nuclear plant accident is a cause of social psychological stresses. A recent study showed that chronic restraint-induced stresses (CRIS) attenuated Trp53 functions and increased carcinogenesis susceptibility of Trp53-heterozygous mice to total-body X-irradiation (TBXI), having a big impact on the academic world and a sensational effect on the public, especially the residents living in radioactively contaminated areas. It is important to investigate the possible modification effects from CRIS on radiation-induced health consequences in Trp53 wild-type (Trp53wt) animals. Prior to a carcinogenesis study, effects of TBXI on the hematopoietic system under CRIS were investigated in terms of hematological abnormality in the peripheral blood and residual damage in the bone marrow erythrocytes using a mouse restraint model. Five-week-old male Trp53wt C57BL/6J mice were restrained 6 h per day for 28 consecutive days, and TBXI (4 Gy) was given on the 8th day. Results showed that CRIS alone induced a marked decrease in the red blood cell (RBC) and the white blood cell (WBC) count, while TBXI caused significantly lower counts of RBCs, WBCs and blood platelets, and a lower concentration of hemoglobin regardless of CRIS. CRIS alone did not show any significant effect on erythrocyte proliferation and on induction of micronucleated erythrocytes, whereas TBXI markedly inhibited erythrocyte proliferation and induced a significant increase in the incidences of micronucleated erythrocytes, regardless of CRIS. These findings suggest that CRIS does not have a significant impact on radiation-induced detrimental effects on the hematopoietic system in Trp53wt mice. (author)

  8. Adenosine kinase inhibition protects against cranial radiation-induced cognitive dysfunction

    Directory of Open Access Journals (Sweden)

    Munjal M Acharya

    2016-06-01

    Full Text Available Clinical radiation therapy for the treatment of CNS cancers leads to unintended and debilitating impairments in cognition. Radiation-induced cognitive dysfunction is long lasting, however, the underlying molecular and cellular mechanisms are still not well established. Since ionizing radiation causes microglial and astroglial activation, we hypothesized that maladaptive changes in astrocyte function might be implicated in radiation-induced cognitive dysfunction. Among other gliotransmitters, astrocytes control the availability of adenosine, an endogenous neuroprotectant and modulator of cognition, via metabolic clearance through adenosine kinase (ADK. Adult rats exposed to cranial irradiation (10 Gy showed significant declines in performance of hippocampal-dependent cognitive function tasks (novel place recognition, novel object recognition, and contextual fear conditioning 1 month after exposure to ionizing radiation using a clinically relevant regimen. Irradiated rats spent less time exploring a novel place or object. Cranial irradiation also led to reduction in freezing behavior compared to controls in the fear conditioning task. Importantly, immunohistochemical analyses of irradiated brains showed significant elevation of ADK immunoreactivity in the hippocampus that was related to astrogliosis and increased expression of glial fibrillary acidic protein (GFAP. Conversely, rats treated with the ADK inhibitor 5-iodotubercidin (5-ITU, 3.1 mg/kg, i.p., for 6 days prior to cranial irradiation showed significantly improved behavioral performance in all cognitive tasks 1 month post exposure. Treatment with 5-ITU attenuated radiation-induced astrogliosis and elevated ADK immunoreactivity in the hippocampus. These results confirm an astrocyte-mediated mechanism where preservation of extracellular adenosine can exert neuroprotection also against radiation-induced pathology. These innovative findings link radiation-induced changes in cognition and CNS

  9. A novel topical protectant for the prevention of β-radiation induced moist desquamation

    International Nuclear Information System (INIS)

    Ma, L.; Wilcock, S.; Rezvani, M.; Hsia, C.

    2003-01-01

    Full text: Effective therapies for the prevention of radiation-induced skin burns that could be readily deployed under a nuclear accident or nuclear terrorism scenario are urgently needed. In this report we describe the efficacy of a novel radioprotectant (DMZ911) in a model of b-radiation induced moist desquamation (MD) in pig skin. DMZ911 is a nitroxide-based topical cream that effectively delivers the nitroxide into viable skin cells. Stable nitroxide compounds have been shown to be effective against both X-ray and ?-ray-induced damage in vivo and in vitro. A pig skin model of β-radiation-induced MD was employed in this study. Exposure to 30 Gy was used to induce skin lesions involving >80% moist desquamation in prescribed test sites on flank skin of female Large White pigs. DMZ911 or placebo was applied to various test sites 2 hours prior to radiation exposure. Lesions were scored based on the area of the test site containing 50% MD (severe) as determined by clinical assessment using blinded observers. Treatment with DMZ911 resulted in a 31% net reduction in MD when compared to placebo treated sites following an 8-week study period. This reduction was observed whether all sites or only those with severe MD were considered. Skin damage (as indicated by MD) from radiation exposure was significantly reduced by 31% (p = 0.05) following pretreatment with the novel topical radioprotectant DMZ911. This observation suggests that skin lesion development from radiation-induced oxidative damage cascades may be successfully inhibited by treatment with DMZ911. This topical therapeutic agent represents a novel treatment for nuclear radiation induced skin injury. DMZ911 may have unique applications in radiation oncology, cosmetic and therapeutic UV, laser, glycolic and dermabrasion procedures

  10. Identification of molecular mechanisms of radiation-induced vascular damage in normal tissues using microarray analyses

    International Nuclear Information System (INIS)

    Kruse, J.J.C.M.; Te Poele, J.A.M.; Russell, N.S.; Boersma, L.J.; Stewart, F.A.

    2003-01-01

    Radiation-induced telangiectasia, characterized by thin-walled dilated blood vessels, can be a serious late complication in patients that have been previously treated for cancer. It might cause cosmetic problems when occurring in the skin, and excessive bleeding requiring surgery when occurring in rectal mucosa. The mechanisms underlying the development of radiation-induced telangiectasia are unclear. The aim of the present study is to determine whether microarrays are useful for studying mechanisms of radiation-induced telangiectasia. The second aim is to test the hypotheses that telangiectasia is characterized by a final common pathway in different tissues. Microarray experiments were performed using amplified RNA from (sham)irradiated mouse tissues (kidney, rectum) at different intervals (1-30 weeks) after irradiation. After normalization procedures, the differentially expressed genes were identified. Control/repeat experiments were done to confirm that the observations were not artifacts of the array procedure. The mouse kidney experiments showed significant upregulation of 31 and 42 genes and downregulation of 9 and 4 genes at 10 and 20 weeks after irradiation, respectively. Irradiated mouse rectum has 278 upregulated and 537 downregulated genes at 10 weeks and 86 upregulated and 29 downregulated genes at 20 weeks. During the development of telangiectasia, 19 upregulated genes and 5 downregulated genes were common to both tissues. Upregulation of Jagged-1, known to play a role in angiogenesis, is particularly interesting in the context of radiation-induced telangiectasia. Microarrays are affective discovery tools to identify novel genes of interest, which may be involved in radiation-induced normal tissue injury. Using information from control arrays (particularly straight color, color reverse and self-self experiments) allowed for a more accurate and reproducible identification of differentially expressed genes than the selection of an arbitrary 2-fold change

  11. Radiation-induced abnormal cortical thickness in patients with nasopharyngeal carcinoma after radiotherapy

    Directory of Open Access Journals (Sweden)

    Jiabao Lin

    2017-01-01

    Full Text Available Conventional MRI studies showed that radiation-induced brain necrosis in patients with nasopharyngeal carcinoma (NPC in years after radiotherapy (RT could involve brain gray matter (GM and impair brain function. However, it is still unclear the radiation-induced brain morphological changes in NPC patients with normal-appearing GM in the early period after RT. In this study, we acquired high-resolution brain structural MRI data from three groups of patients, 22 before radiotherapy (pre-RT NPC patients with newly diagnosed but not yet medically treated, 22 NPC patients in the early-delayed stage after radiotherapy (post-RT-ED, and 20 NPC patients in the late-delayed stage after radiotherapy (post-RT-LD, and then analyzed the radiation-induced cortical thickness alteration in NPC patients after RT. Using a vertex-wise surface-based morphometry (SBM approach, we detected significantly decreased cortical thickness in the precentral gyrus (PreCG in the post-RT-ED group compared to the pre-RT group. And the post-RT-LD group showed significantly increased cortical thickness in widespread brain regions, including the bilateral inferior parietal, left isthmus of the cingulate, left bank of the superior temporal sulcus and left lateral occipital regions, compared to the pre-RT group, and in the bilateral PreCG compared to the post-RT-ED group. Similar analysis with ROI-wise SBM method also found the consistent results. These results indicated that radiation-induced brain injury mainly occurred in the post-RT-LD group and the cortical thickness alterations after RT were dynamic in different periods. Our findings may reflect the pathogenesis of radiation-induced brain injury in NPC patients with normal-appearing GM and an early intervention is necessary for protecting GM during RT.

  12. Accidental finding in orthodontics – Rhinolith

    Directory of Open Access Journals (Sweden)

    Sukhdeep Singh Kahlon

    2018-01-01

    Full Text Available Rhinolith is a calcareous secretion that occurs in the nasal cavity and is usually discovered during routine radiographic examination as it is rare, unilateral, and asymptomatic. It can sometimes lead to nasal obstruction, fetid odor, and purulent secretion. This case report is about the accidental finding of rhinolith during conventional diagnostic procedure. A 10-year-old female had an ovoid radiopacity in the right side of the nasal cavity. Although the patient had no symptoms of prevalence of this mass, it was found during routine radiographic examination. After the complete investigation of the radiopaque mass with the help of cone-beam computed tomography, the rhinolith was endoscopically removed.

  13. Successful treatment of radiation-induced fibrosis using Cu/Zn-SOD and Mn-SOD: an experimental study

    International Nuclear Information System (INIS)

    Lefaix, Jean-Louis; Delanian, Sylvie; Leplat, Jean-Jacques; Tricaud, Yves; Martin, Michele; Nimrod, Abraham; Baillet, Francois; Daburon, Francois

    1996-01-01

    Purpose: To establish how far liposomal copper/zinc superoxide dismutase (Cu/Zn-SOD) and manganese superoxide dismutase (Mn-SOD), respectively, reduce radiation-induced fibrosis (RIF), using a well-characterized pig model of RIF permitting the design of a controlled laboratory experiment. Methods and Materials: In this model of acute localized gamma irradiation simulating accidental overexposure in humans, three groups of five large white pigs were irradiated using a collimated 192 Ir source to deliver a single dose of 160 Gy onto the skin surface (100%) of the outer side of the thigh. A well-defined block of subcutaneous fibrosis involving skin and skeletal muscle developed 6 months after irradiation. One experimental group of five pigs was then injected i.m. with 10 mg/10 kg b.wt. of Cu/Zn-SOD, twice a week for 3 weeks, and another experimental group of five was injected with 10 mg/10 kg b.wt. of Mn-SOD, three times a week for 3 weeks. Five irradiated control pigs were injected with physiological serum. Animals were assessed for changes in the density of the palpated fibrotic block and in the dimensions of the projected cutaneous surface. Block depth was determined by ultrasound. Physical and sonographic findings were confirmed by autopsy 12-14 weeks after completing SOD injections. The density, length, width, and depth of the fibrotic block, and the areas and volume of its projected cutaneous surface were compared before treatment, 1, 3, and 6 weeks thereafter, and at autopsy, 12-14 weeks after treatment ended. Results: The experimental animals exhibited no change in behaviour and no abnormal clinical or anatomic signs. Whether they were given Cu/Zn- or Mn-SOD, significant and roughly equivalent softening and shrinking of the fibrotic block were noted in all treated animals between the first week after treatment ended and autopsy, when mean regression was 45% for length and width, 30% for depth, and 70% for area and volume. Histologic examination showed

  14. Hematopoietic stem cell expansion : challenges and opportunities

    NARCIS (Netherlands)

    Walasek, Marta A.; van Os, Ronald; de Haan, Gerald; Kanz, L; Fibbe, WE; Lengerke, C; Dick, JE

    2012-01-01

    Attempts to improve hematopoietic reconstitution and engraftment potential of ex vivo-expanded hematopoietic stem and progenitor cells (HSPCs) have been largely unsuccessful due to the inability to generate sufficient stem cell numbers and to excessive differentiation of the starting cell

  15. The biochemistry of hematopoietic stem cell development

    NARCIS (Netherlands)

    P. Kaimakis (Polynikis); M. Crisan (Mihaela); E.A. Dzierzak (Elaine)

    2013-01-01

    textabstractBackground: The cornerstone of the adult hematopoietic system and clinical treatments for blood-related disease is the cohort of hematopoietic stem cells (HSC) that is harbored in the adult bone marrow microenvironment. Interestingly, this cohort of HSCs is generated only during a short

  16. Stem cells and the aging hematopoietic system.

    Science.gov (United States)

    Beerman, Isabel; Maloney, William J; Weissmann, Irving L; Rossi, Derrick J

    2010-08-01

    Advancing age is accompanied by a number of clinically significant conditions arising in the hematopoietic system that include: diminution and decreased competence of the adaptive immune system, elevated incidence of certain autoimmune diseases, increased hematological malignancies, and elevated incidence of age-associated anemia. As with most tissues, the aged hematopoietic system also exhibits a reduced capacity to regenerate and return to normal homeostasis after injury or stress. Evidence suggests age-dependent functional alterations within the hematopoietic stem cell compartment significantly contribute to many of these pathophysiologies. Recent developments have shed light on how aging of the hematopoietic stem cell compartment contributes to hematopoietic decline through diverse mechanisms. Copyright 2010 Elsevier Ltd. All rights reserved.

  17. Accidental radioisotope burns - Management of late sequelae

    Directory of Open Access Journals (Sweden)

    Varghese Bipin

    2010-10-01

    Full Text Available Accidental radioisotope burns are rare. The major components of radiation injury are burns, interstitial pneumonitis, acute bone marrow suppression, acute renal failure and adult respiratory distress syndrome. Radiation burns, though localized in distribution, have systemic effects, and can be extremely difficult to heal, even after multiple surgeries. In a 25 year old male who sustained such trauma by accidental industrial exposure to Iridium192 the early presentation involved recurrent haematemesis, pancytopenia and bone marrow suppression. After three weeks he developed burns in contact areas in the left hand, left side of the chest, abdomen and right inguinal region. All except the inguinal wound healed spontaneously but the former became a non-healing ulcer. Pancytopenia and bone marrow depression followed. He was treated with morphine and NSAIDs, epidural buprinorphine and bupivicaine for pain relief, steroids, antibiotics followed by wound excision and reconstruction with tensor fascia lata(TFL flap. Patient had breakdown of abdominal scar later and it was excised with 0.5 cm margins up to the underlying muscle and the wound was covered by a latissimis dorsi flap. Further scar break down and recurrent ulcers occurred at different sites including left wrist, left thumb and right heel in the next two years which needed multiple surgical interventions.

  18. A Combination of Podophyllotoxin and Rutin Alleviates Radiation-Induced Pneumonitis and Fibrosis through Modulation of Lung Inflammation in Mice

    Directory of Open Access Journals (Sweden)

    Savita Verma

    2017-06-01

    Full Text Available Pneumonitis and pulmonary fibrosis are predominant consequences of radiation exposure, whether planned or accidental. The present study, demonstrates radioprotective potential of a formulation, prepared by combining podophyllotoxin and rutin (G-003M, in mice exposed to 11 Gy thoracic gamma radiation (TGR. Treated mice were observed for survival and other symptomatic features. Formation of reactive oxygen species (ROS/nitric oxide (NO was measured in bronchoalveolar lavage cells. DNA damage and cell death were assessed in alveolar cells by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Total protein (TP, lactate dehydrogenase (LDH, and alkaline phosphatase (ALP were measured in bronchoalveolar lavage fluid (BALF/serum of mice to assess lung vascular permeability. Interleukin-6 (IL-6, tumor necrosis factor-α (TNF-α, transforming growth factor-β1 (TGF-β1, cluster of differentiation 45, inducible nitric oxide synthase (iNOS, and nitrotyrosine were also estimated in lungs/BALF of differentially treated mice. Our observations revealed 100% survival in G-003M-pretreated mice against 66.50% in 11 Gy TGR exposed. Other symptoms like reduction in graying of hair, weight loss, and breathing rate were also observed in pretreated groups. Significant decline in ROS/NO and cell death in formulation pretreated mice were also observed. Decreased level of TP, LDH, and ALP in BALF/serum samples revealed G-003M-induced inhibition in lung permeability. Level of IL-6, TNF-α, and TGF-β1 in the lungs of these mice was found corresponding to control group at 8 weeks posttreatment. On the contrary, these cytokines raised significantly in 11 Gy TGR-exposed mice. Lung pneumonitis and fibrosis were found significantly countered in these mice. The observations revealed that G-003M could regulate immune system by curtailing radiation-induced oxidative and inflammatory stress, which has helped in minimizing radiation-inflicted pneumonitis and

  19. Mechanistic aspects of radioprotection by todralazine hydrochloride, a hematopoietic stem cell expanding agent

    International Nuclear Information System (INIS)

    Dimri, Manali; Joshi, Jaidev; Jain, Sanjoli; Ghosh, Subhajit; Srivastva, Nitisha; Prem Kumar, Indracanti; Chakrabarti, Rina

    2014-01-01

    Previously, we have reported todralazine hydrochloride, an antihypertensive drug, as a radioprotector and hematopoietic stem cell (HSC) expanding agent. The present study aims at unraveling mechanistic aspects of its radioprotective and HSC expanding potential. Zebrafish Tg (cmyb:GFP) embryos treated with 5 μM todralazine from 24-36 hours post fertilization (hpf), increased the number of HSCs (∼ 2 folds) at aorta gonad mesonephros (AGM) region. Similarly, the expression of HSC marker genes, runx1 (3.3 folds) and cMyb (1.4 folds) were also found to be increased. Further, todralazine also accelerated hematopoietic lineage production, erythropoiesis, as evaluated in chemical induced anemic model in zebrafish. Genome wide expression changes in todralazine treated embryos (from 24-36 hpf) using microarray, revealed up and down regulation of 645 and 429 genes respectively. Pathway analysis using DAVID database strongly suggested up regulation of wnt pathway (p<0.019253), which is known to involve in HSC expansion, in todralazine pre-treated embryos. NOS1, known to have its role in HSC expansion through wnt pathway, has been significantly upregulated (1.54 folds; q PCR) by todralazine treatment (from 24-36 hpf). Todralazine treatment (∼30 minutes; 20 Gy) led to a significant upregulation of antioxidant genes (SOD, catalase), DNA damage response genes (p53, p21, GADD45) and nucleotide excision repair genes (XPC, XPA, XPF, XPD) when compared to irradiated control. Immunohistochemical analysis of DNA damage marker (γH2AX) (30 minutes post irradiation), further supported radiation induced DNA damage and protection by todralazine pre-treatment. Corroborating these results, pre-irradiation treatment of todralazine reduced radiation induced apoptosis (caspase 3 assay). Overall, the results suggest that, todralazine protects zebrafish from radiation induced damages by upregulating antioxidant defense system, DNA damage recognition, DNA repair machinery and by reducing cell

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Direct evaluation of radiation damage in human hematopoietic progenitor cells in vivo

    International Nuclear Information System (INIS)

    Kyoizumi, Seishi; McCune, J.M.; Namikawa, Reiko

    1994-01-01

    We have developed techniques by which normal functional elements of human bone marrow can be implanted into immunodeficient C.B-17 scid/scid (SCID) mice. Afterward, long-term multilineage human hematopoiesis is sustained in vivo. We evaluated the effect of irradiation on the function of human bone marrow with this in vivo model. After whole-body X irradiation of the engrafted animals, it was determined that the D 0 value of human committed progenitor cells within the human marrow was 1.00 ± 0.09 (SEM) Gy for granulocyte-macrophage colony-forming units (CFU-GM) and 0.74 ± 0.12 Gy for erythroidburst-forming units (BFU-E). The effects of irradiation on the hematopoietic elements were reduced when the radioprotective agent WR-2721 was administered prior to irradiation. After low-dose irradiation, recovery of human granulocyte colony-stimulating factor (G-CSF). This small animal model may prove amenable for the analysis of the risk of the exposure of humans to irradiation as well as for the development of new modalities for the prevention and treatment of radiation-induced hematopoietic damage. 41 refs., 5 figs., 1 tab

  2. Protective effects of HemoHIM on immune and hematopoietic systems against γ-irradiation.

    Science.gov (United States)

    Park, Hae-Ran; Jo, Sung-Kee; Jung, Uhee; Yee, Sung-Tae; Kim, Sung-Ho

    2014-02-01

    We examined the effect of HemoHIM on the protective efficacy of hematopoietic stem cells and on the recovery of immune cells against sublethal doses of ionizing radiation. Two-month-old mice were exposed to γ-rays at a dose of 8, 6.5, or 5 Gy for a30-day survival study, endogenous spleen colony formation, or other experiments, respectively. HemoHIM was injected intraperitoneally before and after irradiation. Our results showed that HemoHIM significantly decreased the mortality of sublethally irradiated mice. The HemoHIM administration decreased the apoptosis of bone marrow cells in irradiated mice. On the other hand, HemoHIM increased the formation of endogenous spleen colony in irradiated mice. In irradiated mice, the recovery of total leukocytes in the peripheral blood and lymphocytes in the spleen were enhanced significantly by HemoHIM. Moreover, the function of B cells, T cells, and NK cells regenerated in irradiated mice were significantly improved by the administration of HemoHIM. HemoHIM showed an ideal radioprotector for protecting hematopoietic stem cells and for accelerating the recovery of immune cells. We propose HemoHIM as a beneficial supplement drug during radiotherapy to alleviate adverse radiation-induced effects for cancer patients. Copyright © 2013 John Wiley & Sons, Ltd.

  3. The Chernobyl – Thirty Years After The Post – Accidental Radiological – Hygienic and Medical Consequences

    Directory of Open Access Journals (Sweden)

    G. G. Onishchenko

    2016-01-01

    Full Text Available As the result of the Chernobyl NPP accident more than 200 thousand square kilometers of the European territories were contaminated by Cs-137 in the amount of above 37 kBq/m2 (1 Ci/km2 . Belorussia, Russia and Ukraine amount up to 70% of this entire affected area. More than 600 000 people were engaged in the accidental cleanup operations, 340000 were evacuated or relocated within 1986-1991. The early stage evacuation efficacy is confirmed by the absence of acute radiation syndrome among the population and by the prevented collective dose which amounts to no less than 10 000 man/Sv. The effective measure to reduce the internal radiation dose to the population at the early accidental stage was introduction of maximum tentative permissive levels of radionuclide content in the foodstuffs.Among the identified post -accident medical consequences of the Chernobyl is the radiation syndrome found in 134 emergency cleanup workers within the first 24 hours of the accident’s development. Out of that number, 28 people died within the first four months, 19 people died before 2006. The accident’s liquidators developed radiation -induced leukemia ( the attributive risk value is 45-60% . People exposed to high radiation doses display the statistically significant 18% morbidity increase of all types of solid cancers at the doses above 150 mSv. There is the statistically significant information indicating the increased amount of thyroid cancer morbidity among those who were just children and teenagers at the time of the accident. The adverse psychological consequences are accounted for not just the fear of overexposure but also for the disturbance of the habitual lifestyle especially mindful of the forced relocation.The longterm protection measures, radionuclide decay and selfcleaning of the contaminated areas resulted in the drastic reduction of the population dose in the radioactively contaminated territories. In 2015, only in some settlements of the Briansk

  4. The effect of additives on the radiation-induced coloration of photochromic dithienylethene derivatives

    International Nuclear Information System (INIS)

    Irie, Setsuko; Irie, Masahiro

    2002-01-01

    The effect of the addition of metal complexes and aromatic compounds on the radiation-induced coloration of poly-styrene films containing 1,2-bis (2-methyl-5-phenyl-3-thienyl) perfluorocyclopentene was examined to develop a sensitive reusable color plastic dosimeter. By the addition of metal complexes, the radiation sensitivity increased along with an increase in the atomic numbers. When aromatic compounds, such as naphthalene, biphenyl, and acenaphthene, were added to the polymer film, the coloration sensitivity increased, while the addition of anthracene and pyrene decreased the sensitivity. Excitation energy transfer from the sensitizers to the dithienylethene is considered to play an important role in the radiation-induced coloration in polystyrene films containing the additives. (author)

  5. Radiation-induced coloration of photochromic dithienylethene derivatives in polymer matrices

    International Nuclear Information System (INIS)

    Irie, Setsuko; Irie, Masahiro

    2000-01-01

    The high-energy radiation-induced coloration of photochromic dithienylethenes was studied in various polymer matrices with the aim of developing a reusable color plastic dosimeter. Upon γ-irradiation, polystyrene films containing 1,2-bis(2,5-dimethyl-3-thienyl)perfluorocyclopentene 1a and 1,2-bis(2-methyl-5-phenyl-3-thienyl)perfluorocyclopentene 2a turned red and blue, respectively. The red and blue colors disappeared upon irradiation with visible light, and the films could be reused. In both films the absorption intensities of the colors increased linearly with the absorbed dose. Although radiation-induced coloration was clearly detected in polystyrene films, a color change was scarcely observed in poly(methyl methacrylate) (PMMA) and poly(N-vinyl carbazole) containing 1a and 2a. Excitation energy transfer from polymers to dithienylethenes is considered to play a role in the coloration process in polymer films. (author)

  6. Radiation-induced leiomyosarcoma of the great vessels presenting as superior vena cava syndrome

    International Nuclear Information System (INIS)

    Weiss, K.S.; Zidar, B.L.; Wang, S.

    1987-01-01

    A patient with a pleomorphic intravascular leiomyosarcoma of the great vessels of the neck and mediastinum presented clinically with a superior vena cava syndrome. A latent period of 29 years elapsed between receiving orthovoltage radiation to the neck and right side of chest to treat recurrent ganglioneuroblastoma, and the appearance of a leiomyosarcoma and subsequent recurrences. The patient underwent partial resection of the tumor, received adjunct chemotherapy, and was shown to be free of disease by clinical tests and by magnetic resonance imaging (MRI) 17 months after completion of chemotherapy. The criteria for the diagnosis of radiation-induced sarcomas are reviewed in relation to the present case. The critical role of magnetic resonance imaging in both the diagnosis and continued follow-up of the patient is described. This would appear to be the first reported case of radiation-induced intravascular leiomyosarcoma of the great vessels of the neck and mediastinum presenting as a superior vena cava syndrome

  7. A kinetic-based model of radiation-induced intercellular signalling.

    Directory of Open Access Journals (Sweden)

    Stephen J McMahon

    Full Text Available It is now widely accepted that intercellular communication can cause significant variations in cellular responses to genotoxic stress. The radiation-induced bystander effect is a prime example of this effect, where cells shielded from radiation exposure see a significant reduction in survival when cultured with irradiated cells. However, there is a lack of robust, quantitative models of this effect which are widely applicable. In this work, we present a novel mathematical model of radiation-induced intercellular signalling which incorporates signal production and response kinetics together with the effects of direct irradiation, and test it against published data sets, including modulated field exposures. This model suggests that these so-called "bystander" effects play a significant role in determining cellular survival, even in directly irradiated populations, meaning that the inclusion of intercellular communication may be essential to produce robust models of radio-biological outcomes in clinically relevant in vivo situations.

  8. Radiation-induced segregation of deuterium in austenitic steels. Communication 1. Role of titanium

    International Nuclear Information System (INIS)

    Arbuzov, V.L.; Raspopova, G.A.; Sagaradze, V.V.; Pecherkina, N.L.; Druzhkov, A.P.; Shal'nov, K.V.; Zuev, Yu.N.

    2004-01-01

    Using the method of nuclear reactions at room temperature a titanium effect on ion radiation induced segregation (RIS) of deuterium in steels Kh16N15M3 and Kh16N15M3T1 is studied. The certification of studied specimen microstructure is carried out with the help transmission electron, scanning electron and tunnel microscopy. It is revealed that particles of titanium-bearing phases (TiC and γ-phase (Ni 3 Ti)) in initial steel structure serve as deuterium traps and intensify RIS. It is assumed that the difference in rates of segregation growth with a radiation dose increase for steels studied is associated with radiation-induced formation of γ'-phase in the steel with titanium. It is shown that anomalous instability of collecting type segregation is inherent in both titanium-bearing and titanium-free steels [ru

  9. Recombination of charge carriers on radiation-induced defects in silicon doped by transition metals impurities

    CERN Document Server

    Kazakevich, L A

    2003-01-01

    It has been studied the peculiarities of recombination of nonequilibrium charge carriers on radiation-induced defects in received according to Czochralski method p-silicon (p approx 3 - 20 Ohm centre dot cm), doped by one of the impurities of transition metals of the IV-th group of periodic table (titanium, zirconium, hafnium). Experimental results are obtained out of the analysis of temperature and injection dependence of the life time of charge carriers. The results are explained taking into consideration the influences of elastic stress fields created by the aggregates of transition metals atoms on space distribution over the crystal of oxygen and carbon background impurities as well as on the migration of movable radiation-induced defects during irradiation. (authors).

  10. Radiation-induced preparation of bimetallic nanoparticles in the films of interpolyelectrolyte complexes

    Science.gov (United States)

    Klimov, Dmitry I.; Zezina, Elena A.; Zezin, Sergei B.; Yang, Mingshu; Wang, Feng; Shvedunov, Vasiliy I.; Feldman, Vladimir I.; Zezin, Alexey A.

    2018-01-01

    The bimetallic nanostructures are of considerable interest for various prospective applications. This paper reports a generation of the Cu/Ag and Cu/Au nanoparticles in the interpolyelectrolyte films irradiated in aqueous media. It was shown that the radiation-induced reduction of (Cu/Ag) or (Cu/Au) ions in the matrix of poly(acrylic acid)-polyethylenimine complexes led to formation of the nanoparticles with narrow size distribution. The core-shell structure of nanoparticles was demonstrated by the TEM results. According to the X-ray diffraction data, the nanoparticle cores (Ag or Au) are formed at early stage of irradiation, while increase of the absorbed dose results in the growth of copper shell. It was demonstrated that the radiation-induced reduction could be applied for effective preparation of bimetallic nanoparticles directly in the polymer matrix.

  11. Treatment of radiation-induced hemorrhagic gastritis with prednisolone: a case report.

    Science.gov (United States)

    Zhang, Lan; Xie, Xiao-Ying; Wang, Yan; Wang, Yan-Hong; Chen, Yi; Ren, Zheng-Gang

    2012-12-28

    Radiation-induced gastritis is an infrequent cause of gastrointestinal bleeding. It is a serious complication arising from radiation therapy, and the standard treatment method has not been established. The initial injury is characteristically acute inflammation of gastric mucosa. We presented a 46-year-old male patient with hemorrhagic gastritis induced by external radiotherapy for metastatic retroperitoneal lymph node of hepatocellular carcinoma. The endoscopic examination showed diffuse edematous hyperemicmucosa with telangiectasias in the whole muscosa of the stomach and duodenal bulb. Multiple hemorrhagic patches with active oozing were found over the antrum. Anti-secretary therapy was initiated for hemostasis, but melena still occurred off and on. Finally, he was successfully treated by prednisolone therapy. We therefore strongly argue in favor of perdnisolone therapy to effectively treat patients with radiation-induced hemorrhagic gastritis.

  12. Spontaneous perseverative turning in rats with radiation-induced hippocampal damage

    International Nuclear Information System (INIS)

    Mickley, G.A.; Ferguson, J.L.; Nemeth, T.J.; Mulvihill, M.A.; Alderks, C.E.

    1989-01-01

    This study found a new behavioral correlate of lesions specific to the dentate granule cell layer of the hippocampus: spontaneous perseverative turning. Irradiation of a portion of the neonatal rat cerebral hemispheres produced hypoplasia of the granule cell layer of the hippocampal dentate gyrus while sparing the rest of the brain. Radiation-induced damage to the hippocampal formation caused rats placed in bowls to spontaneously turn in long, slow bouts without reversals. Irradiated subjects also exhibited other behaviors characteristic of hippocampal damage (e.g., perseveration in spontaneous exploration of the arms of a T-maze, retarded acquisition of a passive avoidance task, and increased horizontal locomotion). These data extend previously reported behavioral correlates of fascia dentata lesions and suggest the usefulness of a bout analysis of spontaneous bowl turning as a measure of nondiscrete-trial spontaneous alternation and a sensitive additional indicator of radiation-induced hippocampal damage

  13. Effect of radiation induced deep level traps on Si detector performance

    CERN Document Server

    Eremin, V; Li, Z

    2002-01-01

    The main factor, which leads to semiconductor detector degradation in high-energy physics experiments, is the introduction of lattice defects in the detector material produced by radiation. Based on the spectrum of radiation induced defects in the silicon bulk, the overview of effects and mechanisms responsible for the changes in the main detector parameters such as effective concentration of the space charge in the depleted region, space charge sign inversion, charge collection efficiency, and detector breakdown voltage are considered. Special attention is paid to the electric field distortion related with high concentration of radiation induced deep traps, which is the key question for the design of detectors operating at cryogenic temperature. In particular, the charge collection recovery at low temperature, often refereed as the Lazarus effect, and the limitation for the detection rate related to the polarization effect are considered.

  14. Radiation-induced color centers in La-doped PbWO sub 4 crystals

    CERN Document Server

    Deng, Q; Zhu, R Y

    1999-01-01

    This report presents the result of a study on radiation-induced color center densities in La-doped lead tungstate (PbWO sub 4) crystals. The creation and annihilation constants of radiation-induced color centers were determined by using transmittance data measured for a PbWO sub 4 sample before and during sup 6 sup 0 Co gamma-ray irradiation at a dose rate of 15 rad/h. Following a model of color center kinetics, these constants were used to calculate color center densities under irradiations at 100 rad/h. The result was found to be in good agreement with experimental data, indicating that the behaviour of PbWO sub 4 crystals under irradiation can be predicted according to this model.

  15. Overexpression of p53, MDM2 proteins in some atr radiation-induced skin ulcers

    International Nuclear Information System (INIS)

    Gu Qingyang; Gao Yabing; Wang Dewen; Cui Yufang; Zhao Po; Yang Zhixiang; Zhou Jie

    2000-01-01

    An animal model of radiation-induced skin ulcer was set up with 140 rats, which were locally irradiated with 35-55 Gy γ-rays. The pathological changes were observed for 1 year. Immunohistochemical studies were performed in 72 rat radiation skin ulcer specimens using anti-p53 and anti-MDM2 proteins polyclonal antibodies. The results showed that the positive rate for overexpression of p53 protein was 9.7%, and for that of MDM2 was 19.4%. The overexpression of p53 was mainly seen in the nuclei of activated squamous epithelial cells, and in fibroblasts, endotheliocytes in deeper part of the skin ulcers. The overexpression of MDM2 had the same localizations. It is suggested that the changes of p53 and MDM2, genes and proteins, may be related to the cancer transformation and poor healing of radiation-induced skin ulcers

  16. Effects of tobacco-smoke on radiation-induced pneumonitis in rats

    International Nuclear Information System (INIS)

    Nilsson, K.; Henriksson, R.; Cai, Y.-Q.; Hellstroem, S.; Bjermer, L.; Hoernqvist Bylunds, S.

    1992-01-01

    To investigate the effect of exposure to tobacco smoke (TS) on the development of irradiation-induced pneumonitis in rats, five groups of animals were investigated including controls (C), tobacco smoke exposed (S), irradiated (RNS) and irradiated and tobacco smoke exposed (RS). An additional group (RS/NS) was exposed to tobacco before irradiation but not afterwards. Results indicate that smoking suppresses the radiation-induced inflammation but to a lesser degree affects the radiation-induced increase in membrane permeability as reflected by increased protein levels in BAL. Moreover, the marked effects on the numbers of mast cells and neutrophils in the RS group may indicate that these cells play an important role in the mechanism by which tobacco smoke modulates the effects of irradiation. When exposure to tobacco smoke was terminated immediately after irradiation (RS/NS), the inflammatory response was unaffected. (author)

  17. Radiation-induced hemorrhagic cystitis effectively treated with hyperbaric oxygen therapy. A case report

    International Nuclear Information System (INIS)

    Yamaguchi, Noriya; Yao, Akihisa; Honda, Masashi; Isoyama, Tadahiro; Sejima, Takehiro; Takenaka, Atsushi

    2014-01-01

    We report a case of radiation induced hemorrhagic cystitis successfully treated with hyperbaric oxygen therapy. A 70-year-old man underwent radical prostatectomy for localized carcinoma in 2002. Due to a positive surgical margin he received 66 Gy of radiation therapy to the prostatic bed. Five years after completion of the radiation therapy, gross hematuria appeared. The patient was diagnosed with radiation-induced hemorrhagic cystitis. Although the hemorrhage was initially improved by conservative therapy, the patient was admitted to our hospital in April 2012 to receive hyperbaric oxygen therapy because the hemorrhage had become resistant to various other therapies. He received 42 trials of hyperbaric oxygen therapy, which resulted in complete remission of the hemorrhage. The patient has remained free of recurrence of gross hematuria for a period of 10 months since the hyperbaric oxygen therapy. (author)

  18. Synergistic effects in radiation-induced particle ejection from solid surfaces

    International Nuclear Information System (INIS)

    Itoh, Noriaki

    1990-01-01

    A description is given on radiation-induced particle ejection from solid surfaces, emphasizing synergistic effects arising from multi-species particle irradiation and from irradiation under complex environments. First, it is pointed out that synergisms can be treated by introducing the effects of material modification on radiation-induced particle ejection. As examples of the effects of surface modification on the sputtering induced by elastic encounters, sputtering of alloys and chemical sputtering of graphite are briefly discussed. Then the particle ejection induced by electronic encounters is explained emphasizing the difference in the behaviors from materials to materials. The possible synergistic effects of electronic and elastic encounters are also described. Lastly, we point out the importance of understanding the elementary processes of material-particle interaction and of developing computer codes describing material behaviors under irradiation. (author)

  19. Effect of microstructure on radiation induced segregation and depletion in ion irradiated SS316 steel

    International Nuclear Information System (INIS)

    Jin, Hyung Ha; Kwon, Sang Chul; Kwon, Jun Hyun

    2011-01-01

    Irradiation assisted stress corrosion cracking (IASCC), void swelling and irradiation induced hardening are caused by change of characteristics of material by neutron irradiation, stress state of material and environmental situation. It has been known that chemical compositions varies at grain boundary (GB) significantly with fluence level and the depletion of Cr element at GB has been considered as one of important factors causing material degradation, especially, IASCC in austenitic stainless steel. However, experimental results of IASCC under PWR condition were directly not connected with Cr depletion phenomenon by neutron irradiation. Because the mechanism of IASCC under PWR has not yet been clearly understood in spite of many energetic researches, fundamental researches about radiation induced segregation and depletion in irradiated austenitic stainless steels have been attracted again. In this work, an effect of residual microstructure on radiation induced segregation and depletion of alloy elements at GB was investigated in ion irradiated SS316 steel using transmission electron microscope (TEM) with energy dispersive spectrometer (EDS)

  20. Modeling Radiation-Induced Degradation in Top-Gated Epitaxial Graphene Field-Effect-Transistors (FETs

    Directory of Open Access Journals (Sweden)

    Jeong-S. Moon

    2013-07-01

    Full Text Available This paper investigates total ionizing dose (TID effects in top-gated epitaxial graphene field-effect-transistors (GFETs. Measurements reveal voltage shifts in the current-voltage (I-V characteristics and degradation of carrier mobility and minimum conductivity, consistent with the buildup of oxide-trapped charges. A semi-empirical approach for modeling radiation-induced degradation in GFETs effective carrier mobility is described in the paper. The modeling approach describes Coulomb and short-range scattering based on calculations of charge and effective vertical field that incorporate radiation-induced oxide trapped charges. The transition from the dominant scattering mechanism is correctly described as a function of effective field and oxide trapped charge density. Comparison with experimental data results in good qualitative agreement when including an empirical component to account for scatterer transparency in the low field regime.

  1. Preparation and characterization of intrinsically coloured polymers using high energy radiation induced processes

    International Nuclear Information System (INIS)

    Guthrie, J.T.

    1978-07-01

    Information on the development in research is given in the utilization of high energy radiation sources in polymerizations and on polymer characterization in the following three areas: studies on the nitrile-styrene system, studies on the radiation induced polymerization of 2-vinyl anthraquinone and the graft polymerization of vinyl monomers onto cellulose in the DMSO/HCHO/cellulose system. Within the framework of research in radiation induced polymerization, samples of 2-vinyl anthraquinone were subjected to X-ray diffraction and e.s.r. examinations and the kinetics and mechanism of γ-ray induced solution polymerization of 2-vinyl anthraquinone in methylene chloride and dimethyl sulfoxide was investigated. Methylene chloride was found to be an efficient solvent for poly(2-vinyl anthraquinone). The rate of polymerization in methylene chloride was 10 3 times greater than that obtained using dimethyl sulfoxide as solvent

  2. Anti-apoptotic peptides protect against radiation-induced cell death

    International Nuclear Information System (INIS)

    McConnell, Kevin W.; Muenzer, Jared T.; Chang, Kathy C.; Davis, Chris G.; McDunn, Jonathan E.; Coopersmith, Craig M.; Hilliard, Carolyn A.; Hotchkiss, Richard S.; Grigsby, Perry W.; Hunt, Clayton R.

    2007-01-01

    The risk of terrorist attacks utilizing either nuclear or radiological weapons has raised concerns about the current lack of effective radioprotectants. Here it is demonstrated that the BH4 peptide domain of the anti-apoptotic protein Bcl-xL can be delivered to cells by covalent attachment to the TAT peptide transduction domain (TAT-BH4) and provide protection in vitro and in vivo from radiation-induced apoptotic cell death. Isolated human lymphocytes treated with TAT-BH4 were protected against apoptosis following exposure to 15 Gy radiation. In mice exposed to 5 Gy radiation, TAT-BH4 treatment protected splenocytes and thymocytes from radiation-induced apoptotic cell death. Most importantly, in vivo radiation protection was observed in mice whether TAT-BH4 treatment was given prior to or after irradiation. Thus, by targeting steps within the apoptosis signaling pathway it is possible to develop post-exposure treatments to protect radio-sensitive tissues

  3. Low temperature diffusion of hydrogenic species in oxide crystals: Radiation induced diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y. [Oak Ridge National Lab., TN (United States); Gonzalez, R. [Universidad `Carlos III` de Madrid (Spain). Dept. de Ingenieria

    1993-10-01

    Normally stable configurations of substitutional protons or deuterons in oxide crystal become highly unstable during ionizing radiation at room temperature, resulting in the displacements of these species. The cross section for radiation-induced-displacements of protons is exceedingly large and is a strong function of temperature. The displacement cross section of protons from cation sites is twice that of deuterons. Diffusion of these species can be induced at temperatures not otherwise possible by thermal means. For example, using electron irradiation near room temperature the O-H bond is readily broken and the hydrogenic species can be channeled along the c-axis in TiO{sub 2} by an applied electric field. Radiation induced displacements of protons from anion sites (hydride ions) at room temperature are also discussed.

  4. Effects of hydroxylated benzaldehyde derivatives on radiation-induced reactions involving various organic radicals

    Science.gov (United States)

    Ksendzova, G. A.; Samovich, S. N.; Sorokin, V. L.; Shadyro, O. I.

    2018-05-01

    In the present paper, the effects of hydroxylated benzaldehyde derivatives and gossypol - the known natural occurring compound - on formation of decomposition products resulting from radiolysis of ethanol and hexane in deaerated and oxygenated solutions were studied. The obtained data enabled the authors to make conclusions about the effects produced by the structure of the compounds under study on their reactivity towards oxygen- and carbon-centered radicals. It has been found that 2,3-dihydroxybenzaldehyde, 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde and 4,6-di-tert-butyl-3-(1,3-dioxane-2-yl)-1,2-dihydroxybenzene are not inferior in efficiency to butylated hydroxytoluene - the industrial antioxidant - as regards suppression of the radiation-induced oxidation processes occurring in hexane. The derivatives of hydroxylated benzaldehydes were shown to have a significant influence on radiation-induced reactions involving α-hydroxyalkyl radicals.

  5. Radiation induced darkening of the optical elements in the Startracker camera

    International Nuclear Information System (INIS)

    White, R.H.; Wirtenson, G.R.

    1993-03-01

    Optical glass flats that closely simulate the elements used in the Startracker lens designs were exposed to doses of ionizing radiation ranging from 0.44 to 1300 krad. Photometer traces determined the transmittance of the samples as a function of both wavelength and dose for wavelengths in the range 300 to 1200 nm. Cerium stabilized glasses used in the radiation stabilized Startracker system showed only a small amount of darkening for doses up to and exceeding 1 Mrad. Glasses used in the unstabilized Startracker design showed significant darkening to visible and ultra-violet spectra for doses as low as 5 krad. Plots of transmittance versus wavelength for various doses are given for each of the Startracker optical elements. Radiation induced absorption parameters that determine the radiation induced absorption coefficient are tabulated and plotted versus wavelength

  6. Analysis of initial events in radiation-induced lymphomagenesis. Investigation of chromosome aberration including translocations

    International Nuclear Information System (INIS)

    Chen Ying

    1995-01-01

    To investigate the contribution of chromosome aberrations in radiation-induced lymphomagenesis, chromosome G-banding analysis of the lymphoma cells (8 groups and 34 kinds of cells), of which each group was derived from a single donor by intra-thymic injection of a limited number of prelymphoma cells, was performed. Many numerical and structural aberrations were observed in the donor-derived T cell lymphomas. Common aberrations including translocations were found almost in the lymphomas of all groups. Translocations between chromosomes 11 and 12, 12 and 15, 7 and 10, 1 and 13, 6 and X were found in D, E, F, G, H, groups, respectively. There were also common aberrations such as trisomy 15 in A and F groups. These results indicate that chromosome aberrations including translocations may be important candidates of initiating events in radiation-induced lymphomagenesis

  7. In vitro growth potential of fibroblasts isolated from pigs with radiation-induced fibrosis

    International Nuclear Information System (INIS)

    Martin, M.; Remy, J.; Daburon, F.

    1986-01-01

    Degenerative processes were studied in pig muscles irradiated with single doses of 30 or 40 Gy. Damaged muscle was gradually replaced by an invasive fibrotic tissue. As a control, surgical muscle exeresis was performed of the same size as the radiation-induced lesions at the same anatomical site. Primary cultures were set up comprising cells freshly extracted from normal dermis, or from tissue exhibiting either normal wound fibrosis or radiation-induced fibrosis. The growth potential of cells taken from the latter region far exceeded that of the two other types; attachment efficiency was higher, and fibronectin was detected early by immunofluorescence. These in vivo and in vitro observations imply that a pathological repair process occurs after localized irradiation. (author)

  8. Detection of radiation-induced lesions in the myc proto-oncogene

    International Nuclear Information System (INIS)

    Grossi, G.F.; Roots, R.; Tobias, C.A.

    1985-01-01

    Alterations in a certain group of genes, the proto-oncogenes, are known to be associated with changes in cell biochemistry and carcinogenesis. The authors chose the Indian male muntjac cell with a total chromosome number of 2N = 7, in which to study the effects of radiation-induced aberrations in the c-myc proto-oncogene. By routine hybridization techniques the authors have shown v-myc homology in total genomic DNA after digestion with Eco R1 and Bam H1. The first task is to identify the chromosomal site of the c-myc gene in these cells. They are doing this by hybridization of the v-myc probe either to the DNA extracted from sorted chromosomes or by the more precise in situ hybridization technique of chromosome spreads. The second task and principal aim is to study the effects of radiation-induced lesions and chromosomal rearrangements in the c-myc gene region

  9. The effects of herbs on the radiation-induced apoptosis in intestinal crypt cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Ho; An, Mi Ra; Nah, Seung Yeol; Lee, Jong Hwan; Kim, Jae Ha; Shin, Dong Ho [Chonnam National Univ., Gwangju (Korea, Republic of); Jo, Sung Kee [KAERI, Daejeon (Korea, Republic of); Jang, Jong Sik [Sangju National Univ., Sangju (Korea, Republic of)

    2001-03-15

    This study was performed to determine the effect of several herbs on radiation-induced apoptosis in jejunal crypt cells. Longyanrou(Euphoris logana), Suanzaoren(Zizyphus vulgaris), Yuanzhi(Polygala tenuifolia), Rensan(Panax ginseng), Fuling(Poria cocos), Muxiang(Saussurea lappa), Chuanxiong(Cnidium offcinale), Baishaoyao(Paeonia lactifolia), Shengma(Cimicifuga heracleifolia), Chaihu(Bupleurum falcatum) and Dongchongxiacao(Paecilomyces japonica) reduced the frequency of radiation-induced apoptosis(p<0.05). Although the mechanisms of this effect remain to be elucidated, these results indicated that Longyanrou, Suanzaoren, Yuanzhi, Rensan, Fuling, Muxiang, Chuanxiong, Baishaoyao, Shengma, Chaihu and Dongchongxiacao might be useful inhibitors of apoptosis, especially since these are relative nontoxic natural products.

  10. The effects of herbs on the radiation-induced apoptosis in intestinal crypt cells

    International Nuclear Information System (INIS)

    Kim, Sung Ho; An, Mi Ra; Nah, Seung Yeol; Lee, Jong Hwan; Kim, Jae Ha; Shin, Dong Ho; Jo, Sung Kee; Jang, Jong Sik

    2001-01-01

    This study was performed to determine the effect of several herbs on radiation-induced apoptosis in jejunal crypt cells. Longyanrou(Euphoris logana), Suanzaoren(Zizyphus vulgaris), Yuanzhi(Polygala tenuifolia), Rensan(Panax ginseng), Fuling(Poria cocos), Muxiang(Saussurea lappa), Chuanxiong(Cnidium offcinale), Baishaoyao(Paeonia lactifolia), Shengma(Cimicifuga heracleifolia), Chaihu(Bupleurum falcatum) and Dongchongxiacao(Paecilomyces japonica) reduced the frequency of radiation-induced apoptosis(p<0.05). Although the mechanisms of this effect remain to be elucidated, these results indicated that Longyanrou, Suanzaoren, Yuanzhi, Rensan, Fuling, Muxiang, Chuanxiong, Baishaoyao, Shengma, Chaihu and Dongchongxiacao might be useful inhibitors of apoptosis, especially since these are relative nontoxic natural products

  11. Explanation of diagnostic criteria for radiation-induced nervous system disease

    International Nuclear Information System (INIS)

    Xing Zhiwei; Jiang Enhai

    2012-01-01

    National occupational health standard-Diagnostic Criteria for Radiation-Induced Nervous System Disease has been issued and implemented by the Ministry of health. This standard contained three independent criteria of the brain, spinal cord and peripheral nerve injury. These three kinds of disease often go together in clinic,therefore,the three diagnostic criteria were merged into radioactive nervous system disease diagnostic criteria for entirety and maneuverability of the standard. This standard was formulated based on collection of the clinical practice experience, extensive research of relevant literature and foreign relevant publications. It is mainly applied to diagnosis and treatment of occupational radiation-induced nervous system diseases, and to nervous system diseases caused by medical radiation exposure as well. In order to properly implement this standard, also to correctly deal with radioactive nervous system injury, the main contents of this standard including dose threshold, clinical manifestation, indexing standard and treatment principle were interpreted in this article. (authors)

  12. Metachronous cancer of both breasts and radiation-induced carcinoma - a case report

    International Nuclear Information System (INIS)

    Marinova, L.; Todorov, Y.; Terziev, I.

    1999-01-01

    A case of female patient presenting bilateral breast cancer, running a metachronous course and radiation-induced laiomyosarcoma is described. A right breast cancer is diagnosed and subjected to complex treatment (pre- and postoperative interstitial radiotherapy, amputation after Patey and chemotherapy course). After a 2-year interval, skin metastases are discovered necessitating ovariectomy, followed by repeated irradiation of the right chest wall with electron beams and polychemotherapy. Twelve years later, leiomyosarcoma involving the operative scar is diagnosed and after 2 years - cancer of the left breast. Proceeding from the results of complex breast cancer treatment, prolongation of the patient's survival in pathologically proved skin metastases is comprehensively discussed. The overall long-term survival is taken to be a precondition of the clinical development of a second primary breast cancer and radiation-induced sarcoma

  13. Treatment of radiation-induced erectile dysfunction with low-intensity extracorporeal shock wave: A case report

    Directory of Open Access Journals (Sweden)

    Chun Wai Chan

    2017-10-01

    Full Text Available Low-intensity extracorporeal shock wave therapy is a new treatment in treating vasculogenic erectile dysfunction. We report a case of low-intensity extracorporeal shock wave therapy used for treating radiation-induced erectile dysfunction. A 66-year-old gentleman with dyslipidemia and smoking presented with radiation-induced erectile dysfunction. Six sessions of low-intensity extracorporeal shock wave therapy were administered. Pre-treatment IIEF- 5 score was 10 and post-treatment IIEF-5 score at one month was 19. Low-intensity extracorporeal shock wave therapy has the potential to treat radiation-induced erectile dysfunction.

  14. Application of radiation-induced graft polymerization to preparation of functional materials

    International Nuclear Information System (INIS)

    Sugo, Takanobu

    2010-01-01

    Radiation-induced graft polymerization is a powerful method for appending various functionalities onto existing fabrics, nonwoven fabrics, fibers, membranes, and beads while maintaining the shape and mechanical strength. By using this method, the author has developed and commercialized functional polymeric materials over 45 years. The materials produced by the fruits of radiation chemistry contributed to the improvement of our lives and environments and the collection of rare metal resources. (author)

  15. 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

  16. 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.

  17. Radiation Induced Crosslinking of Polyethylene in the Presence of Bifunctional Vinyl Monomers

    DEFF Research Database (Denmark)

    Joshi, M. S.; Singer, Klaus Albert Julius; Silverman, J.

    1977-01-01

    Several reports have been published showing that the radiation induced grafting of bifunctional vinyl monomers to low density polyethylene results in a product with an unusually high density of crosslinks. The same grafting reactions are shown to reduce the incipient gel dose by more than a factor...... of fifty. This paper is concerned with the apparent crosslinking produced by the radiation grafting of two monomers to polyethylene: acrylic acid and acrylonitrile....

  18. Tristetraprolin mediates radiation-induced TNF-α production in lung macrophages.

    Directory of Open Access Journals (Sweden)

    Dipankar Ray

    Full Text Available The efficacy of radiation therapy for lung cancer is limited by radiation-induced lung toxicity (RILT. Although tumor necrosis factor-alpha (TNF-α signaling plays a critical role in RILT, the molecular regulators of radiation-induced TNF-α production remain unknown. We investigated the role of a major TNF-α regulator, Tristetraprolin (TTP, in radiation-induced TNF-α production by macrophages. For in vitro studies we irradiated (4 Gy either a mouse lung macrophage cell line, MH-S or macrophages isolated from TTP knockout mice, and studied the effects of radiation on TTP and TNF-α levels. To study the in vivo relevance, mouse lungs were irradiated with a single dose (15 Gy and assessed at varying times for TTP alterations. Irradiation of MH-S cells caused TTP to undergo an inhibitory phosphorylation at Ser-178 and proteasome-mediated degradation, which resulted in increased TNF-α mRNA stabilization and secretion. Similarly, MH-S cells treated with TTP siRNA or macrophages isolated from ttp (-/- mice had higher basal levels of TNF-α, which was increased minimally after irradiation. Conversely, cells overexpressing TTP mutants defective in undergoing phosphorylation released significantly lower levels of TNF-α. Inhibition of p38, a known kinase for TTP, by either siRNA or a small molecule inhibitor abrogated radiation-induced TNF-α release by MH-S cells. Lung irradiation induced TTP(Ser178 phosphorylation and protein degradation and a simultaneous increase in TNF-α production in C57BL/6 mice starting 24 h post-radiation. In conclusion, irradiation of lung macrophages causes TTP inactivation via p38-mediated phosphorylation and proteasome-mediated degradation, leading to TNF-α production. These findings suggest that agents capable of blocking TTP phosphorylation or stabilizing TTP after irradiation could decrease RILT.

  19. Radiation induced depigmentation disorder in two patients with breast cancer: Exploring a rare accompaniment

    International Nuclear Information System (INIS)

    Biswas, A.; Chaudhari, P.B.; Julka, P.K.; Rath, G.K.

    2015-01-01

    Abstract Radiation induced depigmentation disorder is a rare accompaniment. We herein report two patients of bilateral breast cancer developing depigmentation disorder, initially confined to the radiation portal with subsequent generalization within few months of completion of whole breast radiotherapy. Both these patients had no prior history of vitiligo or other autoimmune disorder. This brief report highlights the importance of awareness of this association in appropriate decision making in susceptible patients thereby preventing this morbidity and its psychological ramifications

  20. Current status of battery separator preparation by radiation-induced graft copolymerization

    International Nuclear Information System (INIS)

    Ye Yin; Qiu Shilong

    2006-01-01

    Radiation induced graft copolymerization of functional monomers onto polymeric membrane is an important method for battery separator preparation. In order to satisfy technical requirements of different batteries, the separators should be endowed with unique electrochemical and physiochemical properties, and this can be accomplished by grafting different monomers onto polymer membranes with ionizing radiations. The paper gives a review on recent progresses in this field of research and applications. (authors)

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

    OpenAIRE

    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...

  2. The standardization of acupuncture treatment for radiation-induced xerostomia: A literature review.

    Science.gov (United States)

    Li, Ling-Xin; Tian, Guang; He, Jing

    2016-07-01

    To assess the relative standardization of acupuncture protocols for radiation-induced xerostomia. A literature search was carried out up to November 10, 2012 in the databases PubMed/MEDLINE, EMBASE and China National Knowledge Infrastruction with the terms: radiation-induced xerostomia, acupuncture, acupuncture treatment, and acupuncture therapy. Five ancient Chinese classic acupuncture works were also reviewed with the keywords "dry mouth, thirst, dry tongue, dry eyes and dry lips" to search the effective acupuncture points for dry mouth-associated symptoms in ancient China. Twenty-two full-text articles relevant to acupuncture treatment for radiation-induced xerostomia were included and a total of 48 acupuncture points were searched in the 5 ancient Chinese classic acupuncture works, in which the most commonly used points were Chengjiang (CV24), Shuigou (GV 26), Duiduan (GV 27), Jinjin (EX-HN 12), and Yuye (EX-HN 13) on head and neck, Sanjian (LI 3), Shangyang (LI 1), Shaoshang (LU 11), Shaoze (SI 1), Xialian (LI 8) on hand, Fuliu (KI 7), Dazhong (KI 4), Zuqiaoyin (GB 44), Taichong (LR 3), Zhaohai (KI 6) on foot, Burong (ST 19), Zhangmen (LR 13), Tiantu (CV 22), Qimen (LR 14) on abdomen, Feishu (BL 13), Danshu (BL 19), Xiaochaogshu (BL 27), Ganshu (BL 18) on back, Shenmen (TF 4), Shen (CO10, Kidney), Yidan (CO11, Pancreas) and Pi (CO13, Spleen) on ear. There were considerable heterogeneities in the current acupuncture treatment protocols for radiation-induced xerostomia. Based on the results of the review and the personal perspectives, the authors provide a recommendation for manual acupuncture protocols in treating radiationinduced xerostomia patients with head and neck cancer.

  3. Hesperidin as radioprotector against radiation-induced lung damage in rat: A histopathological study

    Directory of Open Access Journals (Sweden)

    Gholam Hassan Haddadi

    2017-01-01

    Full Text Available Reactive oxygen species (ROS are generated by ionizing radiation, and one of the organs commonly affected by ROS is the lung. Radiation-induced lung injury including pneumonia and lung fibrosis is a dose-limiting factor in radiotherapy (RT of patients with thorax irradiation. Administration of antioxidants has been proved to protect against ROS. The present study was aimed to assess the protective effect of hesperidin (HES against radiation-induced lung injury of male rats. Fifty rats were divided into three groups. G1: Received no HES and radiation (sham. G2: Underwent γ-irradiation to the thorax. G3: Received HES and underwent γ-irradiation. The rats were exposed to a single dose of 18 Gy using cobalt-60 unit and were administered HES (100 mg/kg for 7 days before irradiation. Histopathological analysis was performed 24 h and 8 weeks after RT. Histopathological results in 24 h showed radiation-induced inflammation and presence of more inflammatory cells as compared to G1 (P < 0.05. Administration of HES significantly decreased such an effect when compared to G2 (P < 0.05. Histopathological evaluation in 8 weeks showed a significant increase in mast cells, inflammation, inflammatory cells, alveolar thickness, vascular thickness, pulmonary edema, and fibrosis in G2 when compared to G1 (P < 0.05. HES significantly decreased inflammatory response, fibrosis, and mast cells when compared to G2 (P < 0.05. Administration of HES resulted in decreased radiation pneumonitis and radiation fibrosis in the lung tissue. Thus, the present study showed HES to be an efficient radioprotector against radiation-induced damage in the lung of tissue rats.

  4. A comparison of artificial saliva and pilocarpine in radiation-induced xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Davies, A.N.; Singer, J. (Saint Thomas' Hospital, London (United Kingdom). South East London Radiotherapy Dept.)

    1994-08-01

    Twenty patients with radiation-induced xerostomia were entered into a prospective randomized crossover study comparing a mucin-based artificial saliva (Saliva Orthana) and a mouthwash containing pilocarpine (5 mg three times a day). Overall the patients found that the pilocarpine mouthwash was more effective than the artificial saliva in relieving their symptoms (p = 0.04), and 47 per cent of the patients wanted to continue with this treatment after the study had finished. (author).

  5. Radiation-induced cranial nerve palsy: hypoglossal nerve and vocal cord palsies

    Energy Technology Data Exchange (ETDEWEB)

    Takimoto, Toru; Saito, Yasuo; Suzuki, Masayuki; Nishimura, Toshirou (Kanazawa Univ. (Japan). School of Medicine)

    1991-01-01

    Cranial nerve palsies are an unexpected complication of radiotherapy for head and neck tumours. We present a case of this radiation-induced cranial palsy. An 18-year-old female with nasopharyngeal carcinoma developed a right hypoglossal nerve palsy 42 months after cancericidal doses of radiotherapy. In addition, she developed a bilateral vocal cord palsy 62 months after the therapy. Follow-up over four years has demonstrated no evidence of tumour recurrence and no sign of neurological improvement. (author).

  6. 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.

  7. Identification of genetic modifiers of susceptibility to radiation-induced lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Balmain, Allan [University of California, San Francisco, CA (United States)

    2007-03-28

    The specific aims of this project were as follows: Aim 1: Identify mouse genetic loci that affect the survival time of mice post radiation. Aim 2: Identify somatic genetic alterations that are indicative of tumor suppressor and oncogene loci involved in radiation-induced cancers. Aim 3: Identify candidate radiation susceptibility genes by gene expression microarray analysis of the radiation response in normal tissues or in tumors from the strains used for aims 1 and 2.

  8. The contribution of endogenous and exogenous effects to radiation-induced damage in the bacterial spore

    International Nuclear Information System (INIS)

    Jacobs, G.P.; Samuni, A.; Czapski, G.

    1985-01-01

    Radical scavengers such as polyethylene glycol 400 and 4000 and bovine albumin have been used to define the contribution of exogenous and endogenous effects to the gamma-radiation-induced damage in aqueous buffered suspensions of Bacillus pumilus spores. The results indicate that this damage in the bacterial spore is predominantly endogenous both in the presence of 1 atmosphere of oxygen, and in anoxia. (author)

  9. A selenocysteine derivative therapy affects radiation-induced pneumonitis in the mouse.

    Science.gov (United States)

    Kunwar, Amit; Jain, V K; Priyadarsini, K I; Haston, Christina K

    2013-10-01

    The mechanism leading to the radiation-induced lung response of pneumonitis is largely unknown. Here we investigated whether treatment with 3,3'-diselenodipropionic acid (DSePA), which reduces radiation-induced oxidative stress in acute response models, decreases the lung response to irradiation. Mice of the C3H/HeJ (alveolitis/pneumonitis-responding) strain received 18 Gy whole-thorax irradiation, and a subset of these mice was treated with DSePA (2 mg/kg) three times per week, beginning at 2 hours after radiation treatment, and continuing in the postirradiation period until death because of respiratory distress symptoms. DSePA treatment increased the postirradiation survival time of mice by an average of 32 days (P = 0.0002). Radiation-treated and DSePA-treated mice presented lower levels of lipid peroxidation and augmented glutathione peroxidase in the lungs, compared with those levels measured in mice receiving radiation only, when mice receiving radiation only were killed because of distress symptoms, whereas catalase and superoxide dismutase levels did not show consistent differences among treatment groups. DSePA treatment decreased pneumonitis and the numbers of mast cells, neutrophils, and lymphocytes in the lungs and bronchoalveolar lavage, respectively, of irradiated mice relative to mice exposed to radiation alone. DSePA treatment also decreased the radiation-induced increase in granulocyte colony-stimulating factor levels in the bronchoalveolar lavage and lung-tissue expression of intercellular adhesion molecule-1 and E-selectin, while increasing the expression of glutathione peroxidase-4. We conclude that DSePA treatment reduces radiation-induced pneumonitis in mice by delaying oxidative damage and the inflammatory cell influx.

  10. Radiation-induced lung damage: Etiopathogenesis, clinical features, imaging findings and treatment

    OpenAIRE

    Vasić Ljiljana; Đurđević Predrag

    2012-01-01

    Introduction. This review is related to the mechanism of development of radiation induced pneumonitis, its pathological, clinical and radiological features and therapy. The team treating cancer patients consists of radiation oncologists and oncologists, as well as general practitioners, pulmologists and radiologists for monitoring effects of therapy. Therefore, a different number of specialists should be familiar with the importance of diagnosis in order to avoid differential diagnostic...

  11. Radiation-induced changes in rat endocrine system and their correction by means of adaptogens

    International Nuclear Information System (INIS)

    Alesina, M.Yu.; Arkhipov, N.P.; Karpenko, N.A.; Bogdanova, T.I.; Kozuritsky, V.G.

    2003-01-01

    Endocrine status of experimental animals under chronic influence of both external and internal irradiation in low doses was researched in this work. The influence of adaptation medication preparation (biopolymer Spiruline - BS) on studied indexes is also evaluated. Application of preparation with adaptation-inducing properties - the biopolymer Spiruline for experimental animals at the early irradiation stage partially or completely prevents the development of radiation-induced damages

  12. Radioprotective efficacy of bisarylidene cyclopentanone on electron beam radiation induced oxidative stress in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Darshan Raj, C.G.; Sarojini, B.K.; Musthafa Khaleel, V.; Ramesh, S.R.; Ramakrishna, M.K.; Narayana, B.; Sanjeev, Ganesh

    2010-01-01

    Present study was carried out for evaluating the radioprotective effect of bischalcone (2E, 5E) - 2,5-bis (3-methoxy-4-hydroxy-benzylidene) cyclopentanone (curcumin analog (CA)), on electron beam radiation induced oxidative stress in Drosophila melanogaster adults. The oxidative stress markers and antioxidants included superoxide dismutase (SOD) and catalase (CAT). The oxidative stress was induced at 1.5 Gy. (author)

  13. Morphogenesis of the radiation-induced mutant limb deformity (ld) of the common mouse

    International Nuclear Information System (INIS)

    Selow, J.; Winkler, W.

    1980-01-01

    Findings obtained in the thoracic and pelvic extremities of mice of the incest strain C57B1/10; i.e. animals homozygous with regard to the radiation-induced mutation 'limb deformity', are summarized and compared with the findings in non-deformed mice. Further, the deformities and their causes are discussed against the background of other findings. Conclusions may be drawn for the evaluation of the present findings. (orig./MG) [de

  14. 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.)

  15. A review on radiation-induced nucleation and growth of colloidal metallic nanoparticles

    OpenAIRE

    Abedini, Alam; Daud, Abdul Razak; Abdul Hamid, Muhammad Azmi; Kamil Othman, Norinsan; Saion, Elias

    2013-01-01

    This review presents an introduction to the synthesis of metallic nanoparticles by radiation-induced method, especially gamma irradiation. This method offers some benefits over the conventional methods because it provides fully reduced and highly pure nanoparticles free from by-products or chemical reducing agents, and is capable of controlling the particle size and structure. The nucleation and growth mechanism of metallic nanoparticles are also discussed. The competition between nucleation ...

  16. Consequences of PAI-1 specific deletion in endothelium on radiation-induced intestinal damage

    International Nuclear Information System (INIS)

    Rannou, Emilie

    2015-01-01

    Radiation-induced injury to healthy tissues is a real public health problem, since they are one of the most limiting factors that restrict efficiency of radiation therapy. This problematic is also part of the French Cancer Plan 2014-2017, and involves clinical research. Concepts surrounding the development of radiation-induced damage have gradually evolved into a contemporary and integrated view of the pathogenesis, involving all compartments of target tissue. Among them, endothelium seems to be central in the sequence of interrelated events that lead to the development of radiation-induced damage, although there are rare concrete elements that support this concept. By using new transgenic mouse models, this PhD project provides a direct demonstration of an endothelium-dependent continuum in evolution of radiation-induced intestinal damage. Indeed, changes in the endothelial phenotype through targeted deletion of the gene SERPINE1, chosen because of its key role in the development of radiation enteritis, influences various parameters of the development of the disease. Thus, lack of PAI-1 secretion by endothelial cells significantly improves survival of the animals, and limits severity of early and late tissue damage after a localized small bowel irradiation. Furthermore, these mice partially KO for PAI-1 showed a decrease in the number of apoptotic intestinal stem cells in the hours following irradiation, a decrease in the macrophages infiltrate density one week after irradiation, and a change in the polarization of macrophages throughout the pathophysiological process. In an effort to protect healthy tissues from radiation therapy side effects, without hindering the cancer treatment, PAI-1 seems to be an obvious therapeutic target. Conceptually, this work represents the direct demonstration of the link between endothelium phenotype and radiation enteritis pathogenesis. (author)

  17. Multidisciplinary approach to treatment of radiation-induced chest wall sarcoma.

    Science.gov (United States)

    Kara, H Volkan; Gandolfi, Brad M; Williams, Judson B; D'Amico, Thomas A; Zenn, Michael R

    2016-08-01

    Radiation-induced sarcoma (RIS) is a rare complication following therapeutic external irradiation for lung cancer patients. Patients with RIS may develop recurrence or metastasis of the previous disease and also at high risk for early chest wall complications following operation, which requires close follow-up and multidisciplinary approach. We present a challenging case of RIS with a multidisciplinary teamwork in the decision-making and successful management.

  18. Aortic valve replacement with simultaneous chest wall reconstruction for radiation-induced sarcoma.

    Science.gov (United States)

    Sachithanandan, Anand; Dandekar, Uday; Grimer, Robert; Peart, Francis; Rooney, Stephen J

    2008-01-01

    Sarcomas, a rare complication of radiotherapy for breast carcinoma, have a poor prognosis. We describe a lady with previous mantle radiotherapy exposure, who developed a radiation-induced chest wall sarcoma. She underwent simultaneous aortic valve replacement (AVR) for severe aortic stenosis and excision of the sarcoma. Chest wall reconstruction was achieved with a composite marlex cement plate and a pedicled latissimus dorsi muscle flap.

  19. 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.

  20. Physiological bases and treatment to the radiation-induced emetic reflex

    International Nuclear Information System (INIS)

    Mulen Napoles, Barbara M.; Torres Babie, Priscilla; Ropero Toirac, Ramon de J.

    2002-01-01

    In the course of the specific oncologic treatment, there are frequent complications such as nausea and vomiting. The radiation-induced emetic reflex depends on various factors: primary site of radiation, administered dose, fractioning, irradiated volume, the sensory and psychic characteristics of the patient as well as the chemotherapy association. It is known that the afferent path to the so-called center of vomiting is determined by chemical mediators, protuberance receptors of the intracranial pressure and the unleashing chemoreceptor zone. In radiation-induced emesis, the exact mechanism is yet to be determined but it is known that radiation stimulates the production of chemical mediators and serotonin released by enterochromaffin cells that act upon the center of vomiting and vagal nucleus. Most of patients who are exposed to irradiation of their upper and middle hemibody as well as all the patients exposed to whole-body irradiation present with nausea and vomiting. The therapeutical anti-emetic recommendations are based on the neurochemical control of vomiting and the emetogenic effect of radiotherapy. 5HT3 receptor-antagonists are evaluated as effective agents in the control of radiation-induced emesis