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Laurence Roy - One of the best experts on this subject based on the ideXlab platform.
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Cytogenetic damage analysis in mice chronically exposed to low-dose internal tritium Beta-Particle radiation.
Oncotarget, 2018Co-Authors: Sandrine Roch-lefèvre, Cécile Martin-bodiot, Matthew Flegal, Amelie Freneau, Melinda S. J. Blimkie, Laura Bannister, Heather Wyatt, Joan Francesc Barquinero, Éric Grégoire, Laurence RoyAbstract:// Sandrine Roch-Lefevre 1 , Eric Gregoire 1 , Cecile Martin-Bodiot 1 , Matthew Flegal 2 , Amelie Freneau 1 , Melinda Blimkie 2 , Laura Bannister 2 , Heather Wyatt 2 , Joan-Francesc Barquinero 5 , Laurence Roy 1 , Mohamed Benadjaoud 1 , Nick Priest 2 , Jean-Rene Jourdain 3 and Dmitry Klokov 2, 4 1 Institut de Radioprotection et de Surete Nucleaire, IRSN, Pole Sante et Environnement, Direction de la Sante, Fontenay-aux-Roses, France 2 Radiobiology and Health, Canadian Nuclear Laboratories, Chalk River, Ontario, Canada 3 Institut de Radioprotection et de Surete Nucleaire, IRSN, Direction des Affaires Internationales, Fontenay-aux-Roses, France 4 Department of Biochemistrty, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada 5 Present address at: Autonomous University of Barcelona, Faculty of Biosciences, Cerdanyola del Valles, Spain Correspondence to: Sandrine Roch-Lefevre, email: sandrine.roch-lefevre@irsn.fr Dmitry Klokov, email: dmitry.klokov@cnl.ca Keywords: genotoxicity; chronicle; low-dose; tritium exposure Received: July 29, 2017 Accepted: March 23, 2018 Published: June 08, 2018 ABSTRACT The aim of this study was to carry out a comprehensive examination of potential genotoxic effects of low doses of tritium delivered chronically to mice and to compare these effects to the ones resulting from equivalent doses of gamma-irradiation. Mice were chronically exposed for one or eight months to either tritiated water (HTO) or organically bound tritium (OBT) in drinking water at concentrations of 10 kBq/L, 1 MBq/L or 20 MBq/L. Dose rates of internal β-Particle resulting from such tritium treatments were calculated and matching external gamma-exposures were carried out. We measured cytogenetic damage in bone marrow and in peripheral blood lymphocytes (PBLs) and the cumulative tritium doses (0.009 – 181 mGy) were used to evaluate the dose-response of OBT in PBLs, as well as its relative biological effectiveness (RBE). Neither tritium, nor gamma exposures produced genotoxic effects in bone marrow. However, significant increases in chromosome damage rates in PBLs were found as a result of chronic OBT exposures at 1 and 20 M Bq/L, but not at 10 kBq/L. When compared to an external acute gamma-exposure ex vivo , the RBE of OBT for chromosome aberrations induction was evaluated to be significantly higher than 1 at cumulative tritium doses below 10 mGy. Although found non-existent at 10 kBq/L (the WHO limit), the genotoxic potential of low doses of tritium (>10 kBq/L), mainly OBT, may be higher than currently assumed.
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cytogenetic damage analysis in mice chronically exposed to low dose internal tritium Beta Particle radiation
Oncotarget, 2018Co-Authors: Sandrine Rochlefevre, Matthew Flegal, Amelie Freneau, Melinda S. J. Blimkie, Laura Bannister, Heather Wyatt, Joan Francesc Barquinero, Éric Grégoire, Cecile Martinbodiot, Laurence RoyAbstract:The aim of this study was to carry out a comprehensive examination of potential genotoxic effects of low doses of tritium delivered chronically to mice and to compare these effects to the ones resulting from equivalent doses of gamma-irradiation. Mice were chronically exposed for one or eight months to either tritiated water (HTO) or organically bound tritium (OBT) in drinking water at concentrations of 10 kBq/L, 1 MBq/L or 20 MBq/L. Dose rates of internal β-Particle resulting from such tritium treatments were calculated and matching external gamma-exposures were carried out. We measured cytogenetic damage in bone marrow and in peripheral blood lymphocytes (PBLs) and the cumulative tritium doses (0.009 - 181 mGy) were used to evaluate the dose-response of OBT in PBLs, as well as its relative biological effectiveness (RBE). Neither tritium, nor gamma exposures produced genotoxic effects in bone marrow. However, significant increases in chromosome damage rates in PBLs were found as a result of chronic OBT exposures at 1 and 20 M Bq/L, but not at 10 kBq/L. When compared to an external acute gamma-exposure ex vivo, the RBE of OBT for chromosome aberrations induction was evaluated to be significantly higher than 1 at cumulative tritium doses below 10 mGy. Although found non-existent at 10 kBq/L (the WHO limit), the genotoxic potential of low doses of tritium (>10 kBq/L), mainly OBT, may be higher than currently assumed.
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Cytogenetic damage analysis in mice chronically exposed to low-dose internal tritium Beta-Particle radiation
Oncotarget, 2018Co-Authors: Sandrine Roch-lefèvre, Cécile Martin-bodiot, Matthew Flegal, Amelie Freneau, Melinda S. J. Blimkie, Laura Bannister, Heather Wyatt, Joan Francesc Barquinero, Éric Grégoire, Laurence RoyAbstract:The aim of this study was to carry out a comprehensive examination of potential genotoxic effects of low doses of tritium delivered chronically to mice and to compare these effects to the ones resulting from equivalent doses of gamma-irradiation. Mice were chronically exposed for one or eight months to either tritiated water (HTO) or organically bound tritium (OBT) in drinking water at concentrations of 10 kBq/L, 1 MBq/L or 20 MBq/L. Dose rates of internal β-Particle resulting from such tritium treatments were calculated and matching external gamma-exposures were carried out. We measured cytogenetic damage in bone marrow and in peripheral blood lymphocytes (PBLs) and the cumulative tritium doses (0.009 - 181 mGy) were used to evaluate the dose-response of OBT in PBLs, as well as its relative biological effectiveness (RBE). Neither tritium, nor gamma exposures produced genotoxic effects in bone marrow. However, significant increases in chromosome damage rates in PBLs were found as a result of chronic OBT exposures at 1 and 20 M Bq/L, but not at 10 kBq/L. When compared to an external acute gamma-exposure ex vivo, the RBE of OBT for chromosome aberrations induction was evaluated to be significantly higher than 1 at cumulative tritium doses below 10 mGy. Although found non-existent at 10 kBq/L (the WHO limit), the genotoxic potential of low doses of tritium ( > 10 kBq/L), mainly OBT, may be higher than currently assumed. © Roch-Lefèvre et al.
V. M. Castaño - One of the best experts on this subject based on the ideXlab platform.
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thermoluminescence kinetics parameters of zno exposed to Beta Particle irradiation
Journal of Materials Science, 2017Co-Authors: H A Borbonnunez, R. Bernal, C. Furetta, J L Iriquirazcon, C Cruzvazquez, V Chernov, V. M. CastañoAbstract:In this work, we report the dosimetric characterization and the evaluation of the kinetics parameters of trapping states of ZnO phosphors obtained thought a chemical route. Pellet-shaped samples present thermoluminescence (TL) properties suitable for use as radiation detectors and dosimeters. The glow curve is composed of three peaks with the maxima at about 412, 530 and 600 K. The last peak is located into the temperature range considered most suitable for TL dosimetry applications. The activation energies and the frequency factors of trapping states involved in the TL emission were evaluated using the initial rise method, peak shape methods, and glow curve deconvolution (GCD). The values of the activation energies obtained using peak shape methods agree with those computed from GCD.
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Thermoluminescence of Sc2O3 exposed to Beta-Particle irradiation
Optical Materials, 2014Co-Authors: F. Brown, R. Bernal, Catalina Cruz-vazquez, V. R. Orante-barrón, V.e. Alvarez-montaño, H.a. Borbón-nuñez, Iliana C. Muñoz, V. M. CastañoAbstract:In this work, the thermoluminescence (TL) features of Sc2O3 exposed to Beta Particle irradiation in the dose range from 0.08 to 150 Gy are reported. Characteristic glow curves exhibit two main TL maxima, located at 74 and 192 °C when a 2 °C/s heating rate is used. The TL response as a function of dose exhibits a linear behavior for doses below 70 Gy. We conclude that Sc2O3 is a promising phosphor material for using as TL dosimeter.
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Thermoluminescence of NaF:Eu3+phosphors exposed to Beta Particle irradiation
physica status solidi (c), 2012Co-Authors: A. R. García-haro, R. Bernal, Catalina Cruz-vazquez, George Kitis, V. R. Orante-barrón, V. M. CastañoAbstract:Pellet-shaped NaF:Eu3+ phosphors were synthesized by sintering. When a 5 K/s heating rate was used, the char-acteristic glow curves of Beta Particle irradiated samples exhibited two thermoluminescence (TL) maxima located at 401 K and 498 K, being the higher temperature max-imum the most intense. A peak located between 473 and 523 K is considered to have a position very suitable to assure good thermal stability of the stored TL, so this phosphor is attractive for radiation dosimetry. Beta Particle irradiated samples displayed a TL response that increases as the radiation dose increased in the 0.08 to 42.5 Gy dose range, with a linear behavior below 10 Gy followed by a sublinear one for higher doses. Under storage after irradiation, the TL maximum at 498 K displayed a remarkable stability, and the TL fading revealed that the maximum at 401 K is not a single peak. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
F. Brown - One of the best experts on this subject based on the ideXlab platform.
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Thermoluminescence of ZnO:Na phosphors exposed to Beta Particle irradiation
Optical Materials, 2018Co-Authors: R. Avilés-monreal, R. Bernal, Catalina Cruz-vazquez, F. BrownAbstract:Abstract In this work, the thermoluminescence (TL) characterization of pellet-shaped ZnO:Na phosphors synthesized through a controlled chemical reaction followed by thermal annealing at 900 °C in air is reported. X-Ray diffraction patterns reveal ZnO hexagonal zincite structure for the samples, some of which were exposed to Beta Particle irradiation in the dose range from 0.08 to 2048 Gy in order to study their TL features. The synthesized ZnO:Na samples are more than 200 times more sensitive than ZnO samples synthesized by the same method, and present a 0.02 (1/50) sensitivity relative to the TLD-100 dosimeter.
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Afterglow dosimetry performance of Beta Particle irradiated lithium zirconate.
Applied radiation and isotopes : including data instrumentation and methods for use in agriculture industry and medicine, 2017Co-Authors: T.c. Hernández-pérez, R. Bernal, Catalina Cruz-vazquez, Ch. J. Salas-juárez, F. Brown, A. Mendoza-córdova, R. Avilés-monrealAbstract:In this work, we report for the very first time on the thermoluminescence (TL) and afterglow (AG) properties of Li2ZrO3. The ternary oxide Li2ZrO3 was synthesized by solid state reaction of a mixture of Li2CO3 and ZrO2 subjected to thermal annealing at 400°C for 2h and 1000°C during 24h in air. The characteristic glow curves of Beta Particle irradiated samples exhibit an intense TL emission located around 150°C. From the shape of the TL curve, a 0.4 form factor was determined, suggesting that first order kinetics processes are involved. The afterglow decay curves were recorded after exposure to Beta Particle irradiation in the dose range from 0.5 up to 2kGy. The AG integrated in the time interval from 510 to 600s after radiation exposure shows a linear dependence as a function of the irradiation dose from 0.5 up to 256Gy. A method is proposed to compute the lower detection limit and the AG sensitivity and applied to the studied phosphors. Structural and morphological characterization were carried out by X-ray diffraction and Scanning Electron Microscopy, respectively. From the results presented, it is concluded that the AG response of the synthesized Li2ZrO3 presents features suitable to develop radiation detectors and dosimeters.
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Thermoluminescence of Sc2O3 exposed to Beta-Particle irradiation
Optical Materials, 2014Co-Authors: F. Brown, R. Bernal, Catalina Cruz-vazquez, V. R. Orante-barrón, V.e. Alvarez-montaño, H.a. Borbón-nuñez, Iliana C. Muñoz, V. M. CastañoAbstract:In this work, the thermoluminescence (TL) features of Sc2O3 exposed to Beta Particle irradiation in the dose range from 0.08 to 150 Gy are reported. Characteristic glow curves exhibit two main TL maxima, located at 74 and 192 °C when a 2 °C/s heating rate is used. The TL response as a function of dose exhibits a linear behavior for doses below 70 Gy. We conclude that Sc2O3 is a promising phosphor material for using as TL dosimeter.
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Thermoluminescence of Beta Particle Irradiated LiMgF 3 :X (X=Ce, Er)
MRS Proceedings, 2010Co-Authors: Iliana C. Muñoz, Catalina Cruz-vazquez, V. R. Orante-barrón, F. Brown, R. I. Baldenevro, C. Furetta, R. BernalAbstract:The thermoluminescence (TL) properties of Beta Particle irradiated Ce and Er doped LiMgF 3 phosphors are presented. Pellet-shaped samples were prepared by cool-pressing 74 μm size Particle powder, followed by thermal annealing at 700 °C during 5 h in air atmosphere. Some samples were irradiated with Beta Particles in the dose range from 8 up to 128 Gy. The sensitivity of Er doped samples was greater than the one of Ce-doped. In both cases, a 2 % mol of dopant concentration was used. The TL fading was between 19 % for Ce-doped samples, and 24 % for the Er-doped. The integrated TL increases as dose increases, with no saturation clues. The TL sensitivity of samples exhibited a loss in successive irradiation – readout cycles.
R. Bernal - One of the best experts on this subject based on the ideXlab platform.
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Thermoluminescence of ZnO:Na phosphors exposed to Beta Particle irradiation
Optical Materials, 2018Co-Authors: R. Avilés-monreal, R. Bernal, Catalina Cruz-vazquez, F. BrownAbstract:Abstract In this work, the thermoluminescence (TL) characterization of pellet-shaped ZnO:Na phosphors synthesized through a controlled chemical reaction followed by thermal annealing at 900 °C in air is reported. X-Ray diffraction patterns reveal ZnO hexagonal zincite structure for the samples, some of which were exposed to Beta Particle irradiation in the dose range from 0.08 to 2048 Gy in order to study their TL features. The synthesized ZnO:Na samples are more than 200 times more sensitive than ZnO samples synthesized by the same method, and present a 0.02 (1/50) sensitivity relative to the TLD-100 dosimeter.
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Afterglow dosimetry performance of Beta Particle irradiated lithium zirconate.
Applied radiation and isotopes : including data instrumentation and methods for use in agriculture industry and medicine, 2017Co-Authors: T.c. Hernández-pérez, R. Bernal, Catalina Cruz-vazquez, Ch. J. Salas-juárez, F. Brown, A. Mendoza-córdova, R. Avilés-monrealAbstract:In this work, we report for the very first time on the thermoluminescence (TL) and afterglow (AG) properties of Li2ZrO3. The ternary oxide Li2ZrO3 was synthesized by solid state reaction of a mixture of Li2CO3 and ZrO2 subjected to thermal annealing at 400°C for 2h and 1000°C during 24h in air. The characteristic glow curves of Beta Particle irradiated samples exhibit an intense TL emission located around 150°C. From the shape of the TL curve, a 0.4 form factor was determined, suggesting that first order kinetics processes are involved. The afterglow decay curves were recorded after exposure to Beta Particle irradiation in the dose range from 0.5 up to 2kGy. The AG integrated in the time interval from 510 to 600s after radiation exposure shows a linear dependence as a function of the irradiation dose from 0.5 up to 256Gy. A method is proposed to compute the lower detection limit and the AG sensitivity and applied to the studied phosphors. Structural and morphological characterization were carried out by X-ray diffraction and Scanning Electron Microscopy, respectively. From the results presented, it is concluded that the AG response of the synthesized Li2ZrO3 presents features suitable to develop radiation detectors and dosimeters.
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Afterglow based detection and dosimetry of Beta Particle irradiated ZrO2
Applied radiation and isotopes : including data instrumentation and methods for use in agriculture industry and medicine, 2017Co-Authors: Ch. J. Salas-juárez, Catalina Cruz-vazquez, R. Avilés-monreal, R. BernalAbstract:Abstract In this work, we report on the afterglow (AG) response characterization of commercially available ZrO2. Pellet shaped samples previously annealed in air at 1000 °C during 24 h were exposed to Beta Particle irradiation in the dose range from 0.5 up to 128 Gy and their AG decay curves recorded during 600 s after irradiation exposure. The characteristic glow curves of Beta Particle irradiated ZrO2 show two maxima located around 80 °C and 150 °C. The first one rapidly vanishes at room temperature, giving rise to AG. The integrated AG signal increases as dose increases from 0.5 to 128 Gy, with a linear dependence from 0.5 up to ca. 32 Gy. Excellent reproducibility of the AG response was observed in 10 irradiation – AG readout cycles, showing that the studied ZrO2 samples are reusable. The results here presented show that ZrO2 is a promising material for use as a radiation dosimeter based on the AG phenomenon.
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thermoluminescence kinetics parameters of zno exposed to Beta Particle irradiation
Journal of Materials Science, 2017Co-Authors: H A Borbonnunez, R. Bernal, C. Furetta, J L Iriquirazcon, C Cruzvazquez, V Chernov, V. M. CastañoAbstract:In this work, we report the dosimetric characterization and the evaluation of the kinetics parameters of trapping states of ZnO phosphors obtained thought a chemical route. Pellet-shaped samples present thermoluminescence (TL) properties suitable for use as radiation detectors and dosimeters. The glow curve is composed of three peaks with the maxima at about 412, 530 and 600 K. The last peak is located into the temperature range considered most suitable for TL dosimetry applications. The activation energies and the frequency factors of trapping states involved in the TL emission were evaluated using the initial rise method, peak shape methods, and glow curve deconvolution (GCD). The values of the activation energies obtained using peak shape methods agree with those computed from GCD.
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Thermoluminescence of Sc2O3 exposed to Beta-Particle irradiation
Optical Materials, 2014Co-Authors: F. Brown, R. Bernal, Catalina Cruz-vazquez, V. R. Orante-barrón, V.e. Alvarez-montaño, H.a. Borbón-nuñez, Iliana C. Muñoz, V. M. CastañoAbstract:In this work, the thermoluminescence (TL) features of Sc2O3 exposed to Beta Particle irradiation in the dose range from 0.08 to 150 Gy are reported. Characteristic glow curves exhibit two main TL maxima, located at 74 and 192 °C when a 2 °C/s heating rate is used. The TL response as a function of dose exhibits a linear behavior for doses below 70 Gy. We conclude that Sc2O3 is a promising phosphor material for using as TL dosimeter.
R Nath - One of the best experts on this subject based on the ideXlab platform.
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A novel balloon angioplasty catheter impregnated with Beta-Particle emitting radioisotopes for vascular brachytherapy to prevent restenosis. First in vivo results
European Heart Journal, 2000Co-Authors: Christoph Hehrlein, A Kovacs, G K Wolf, N Yue, R NathAbstract:Background According to early clinical trials, vascular brachytherapy performed prior to or shortly after angioplasty is very effective in reducing restenosis rates. The purpose of this study was to investigate the effects of a novel radioactive catheter that allows simultaneous balloon angioplasty and Beta-Particle irradiation in the prevention of restenosis. Material and Methods The balloon surface of an angioplasty catheter was impregnated with the radioisotope32P. Dosimetry calculations using a Monte Carlo method were performed at a radial distance of 0·2mm from the balloon surface. Rabbit iliac arteries were dilated and simultaneously irradiated with a dose of 20Gy delivered to the adventitia. Control arteries were only dilated and not irradiated. Neointimal areas, cell numbers and the perimeter of the arteries were measured by histomorphometry after 6 weeks. Results Neointima formation was reduced after balloon dilatation and simultaneous Beta-Particle irradiation using the32P impregnated angioplasty catheter as compared to balloon dilatation alone with a non-impregnated catheter (0·09±0·06 vs 0·27±0·09mm2neointimal area and 168±45 vs 360±133 cells/0·05mm2neointima, P
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a novel balloon angioplasty catheter impregnated with Beta Particle emitting radioisotopes for vascular brachytherapy to prevent restenosis first in vivo results
European Heart Journal, 2000Co-Authors: Christoph Hehrlein, A Kovacs, G K Wolf, R NathAbstract:BACKGROUND: According to early clinical trials, vascular brachytherapy performed prior to or shortly after angioplasty is very effective in reducing restenosis rates. The purpose of this study was to investigate the effects of a novel radioactive catheter that allows simultaneous balloon angioplasty and Beta-Particle irradiation in the prevention of restenosis. MATERIAL AND METHODS: The balloon surface of an angioplasty catheter was impregnated with the radioisotope(32)P. Dosimetry calculations using a Monte Carlo method were performed at a radial distance of 0.2 mm from the balloon surface. Rabbit iliac arteries were dilated and simultaneously irradiated with a dose of 20 Gy delivered to the adventitia. Control arteries were only dilated and not irradiated. Neointimal areas, cell numbers and the perimeter of the arteries were measured by histomorphometry after 6 weeks. RESULTS: Neointima formation was reduced after balloon dilatation and simultaneous Beta-Particle irradiation using the(32)P impregnated angioplasty catheter as compared to balloon dilatation alone with a non-impregnated catheter (0.09+/-0.06 vs 0.27+/-0.09 mm(2)neointimal area and 168+/-45 vs 360+/-133 cells/0.05 mm(2)neointima, P<0.001 vs control, respectively). In addition, balloon dilatation with the(32)P impregnated angioplasty catheter increased the vessel perimeter as compared to balloon dilatation with a non-impregnated catheter (4. 7+/-0.2 vs 3.9+/-0.3 mm, P<0.001 vs control). CONCLUSIONS: Simultaneous balloon dilatation and vascular brachytherapy with a novel(32)P impregnated angioplasty catheter markedly reduces restenosis in vivo by preventing neointimal hyperplasia and constrictive vascular remodelling.