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Sample records for 60co irradiated tachyzoites

  1. Evaluation of immunity and protection induced in experimental models by soluble extract of Toxoplasma gondii tachyzoites irradiated by {sup 60}Co; Avaliacao da imunidade e protecao induzida em modelos experimentais por extrato soluvel de taquizoitos de Toxoplasma gondii irradiado por {sup 60}Co

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    Costa, Andrea da

    2013-07-01

    Toxoplasmosis affects 1/3 of the human population and only a vaccine for veterinary use. Gamma radiation alters the proteins making them more immunogenic by oxidation and better antigen presentation in the absence of adjuvants. Radiate soluble extract of RH strain tachyzoites of T. gondii (AgTg), and evaluate its use as a vaccine in BALB/c. Doses below 500Gy not affected and destroyed 2000Gy doses above extract, whereas animals immunized with irradiated extract at 1000, 1500 and 2000Gy had more of specific IgG avidity , compared to native AgTg (p<0,05) . AgTg 1500GY the immunized animals had increased proliferation of splenocytes, phenotyped as CD3+CD4+, CD3+CD8+ and B-lymphocytes immunized animals compared to the native AgTg . Animals immunized by AgTg 1500GY after challenge with strain ME- 49 cystogenic showed lower number of brain cysts and greater survival after challenge with virulent RH. Ionizing radiation in extracts of T. gondii increases the immune response and immune memory in the absence of adjuvants. (author)

  2. Development of irradiator {sup 60}Co sources

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    Mosca, Rodrigo C.; Moura, Eduardo S.; Zeituni, Carlos A.; Mathor, Monica B., E-mail: rcmosca@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    According to a recent report by the International Agency for Research on Cancer (IARC) / WHO (2008-2010), the global impact of cancer more than doubled in 30 years. In this report, it was estimated that occurred about 12 million new cancer cases and 7 million deaths. In Brazil in 2010, with estimates for the year 2011, point to the occurrence of 489,270 new cases of cancer. Among the possibilities for cancer treatment, radiotherapy is one of the most important therapeutic and resources used to combat it. However, inherent complications of treatment can occur such as tiredness, loss of appetite, radiodermatitis and in more extreme cases late radionecrosis. In order to reproduce a point of radionecrosis in the vicinity of radiodermatitis to mimic these effects in animals, producing a model for assessment of tissue repair, we propose the setting up of an irradiator source of collimated {sup 60}Co. The development of was based on 11 sources of {sup 60}Co with 1 mm thickness that were inserted by inference in stainless steel 'gate-source' screw (patent pending) and later adjusted in a cross-shaped arrangement reinforced so that the beam radiation is directed to a target point, saving for other regions around this target point. The main use of this irradiator with sources of {sup 60}Co is just one cause radionecrosis point (target point) of approximately 5 mm{sup 2} with a surrounding and adjacent area of radiodermatitis around about 8 to 10 mm{sup 2} in laboratory animals for subsequent coating with epidermal-dermal matrix populated by a cell culture of human fibroblasts, keratinocytes and mesenchymal stem cells. With that said, its use will be valuable for evaluation of curative treatments against the bone and radionecrosis or palliative treatment rather than as it is currently assumed. (author)

  3. Toxoplasma gondii vs ionizing radiation: cell and humoral immunity in spleen and gut of isogenic mice immunized with {sup 60}Co irradiated tachyzoites; Toxoplasma gondii vs radiacao ionizante: imunidade humoral e celular em baco e intestino de camundongos isogenicos imunizados com taquizoitos irradiados por cobalto 60

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    Galisteo Junior, Andres Jimenez

    2008-07-01

    We are developing a vaccine for toxoplasmosis, using ionizing radiation as a tool. Here we analyzed the production of systemic and intestinal immunity, with protection studies, in several strains of inbred mice, by oral or parenteral route, using 255 Gy irradiated tachyzoites of T. gondii RH strain, with challenge with cysts of ME- 49 strain. C57Bl/6j, BALB/c and C57Bl/6j IFN-{gamma}{sup -/-} mice were immunized with 10{sup 7} irradiated tachyzoites, be parenteral or oral route. Those preparations, both by parenteral or oral routes, induced the production of specific IgG, mainly of the lgG2b subclass, and IgA immunoglobulins in serum, , as determined by ELISA. IgM production was negligible. Parenteral immunized mice showed higher IgG avidity maturation, as compared to oral immunized mice. Fecal excretion of IgG, IgA and IgM was detected in stools of immunized animals, more intense in oral immunized mice. In cellular immunity studies, induced by antigen, with detection of cytokine production by quantitative real-time PCR, there are a great production of IFN-y by spleen cells, with lower levels in Peyer patches cells, where there are a greater IL-2 production. Challenge studies in immunized mice demonstrated protection to infection in all used schedules, greater in BALB/c mice. C57Bl/6j IFN-{gamma} -{sup /-} mice, when immunized, showed no signs of disease and produced similar or greater levels of antibodies than wild type mice. They also excreted S-lgA and S-IgM in stools, but with low numbers of brain cysts in parenteral immunized mice, despite similar mortality. Our data points to a fair possibility of use of those irradiated parasites as an oral vaccine, devised to use for veterinary or wild felines vaccination, reducing the production of oocysts by those hosts and interrupting the chain transmission of human toxoplasmosis. (author)

  4. Pagure {sup 60}Co panoramic irradiation facility; Pagure irradiateur panoramique au {sup 60}Co

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    Puig, J.R.; Laizier, J.; Lorin, M.; Laroche, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    After a description of the various parts of 'PAGURE', a 10 KCi panoramic irradiation facility, and of the operations data, a critic scrutiny is given. From the experience of five years operations, working of the facility can be thought of very satisfying. From the point of view of standardization of irradiation facilities, PAGURE can be taken, in its range, as a standard design. (authors) [French] Apres avoir decrit les differents elements constitutifs de 1'irradiateur panoramique de 10 KCi 'PAGURE' et precise les donnees d'exploitation, on en fait l'examen critique. A la lumiere de cinq annees d'utilisation, le fonctionnement de 1'irradiateur apparait extremement satisfaisant. Dans une perspective de standardisation des appareils, on peut, dans sa gamme, le considerer comme une realisation type. (auteurs)

  5. Immunohistochemical study on effects of [sup 60]Co [gamma] irradiation on salivary gland ducts of rat

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    Saitoh, Kazuhiko (Meikai Univ., Sakato, Saitama (Japan). School of Dentistry)

    1992-09-01

    Cytokeratin distribution in salivary glands was detected by use of polyclonal antikeratin antiserum (TK) and monoclonal antibodies (KL 1, RGE 53, and RPN 1164). The salivary glands of male rats received either 17.82 Gy or 27.97 Gy [sup 60]Co [gamma] irradiation in a single exposure and were then compared immunohistochemically with those of normal rats. Polyclonal anti-keratin antiserum (TK), which reacts with 41-65 KD keratins, stained almost all ducts in normal glands. RPN 1164 (no. 8 keratin) staining was negative in intercalated ducts of normal parotid and submandibular glands, but strongly positive in both striated and excretory ducts of these glands. Monoclonal antibody KL 1 (55-57 KD keratins) and RGE 53 (no. 18 keratin) did not bind to any ductal or acinar epithelia. Only in the sublingual gland were acini positive for TK staining, possibly indicating myoepithelial cells. No effects of [sup 60]Co [gamma] irradiation were apparent regarding keratin distribution in the intercalated in apical cytoplasm by [sup 60]Co [gamma] irradiation. Also, in the excretory duct, the basal side of the cells exhibited weakened staining following [sup 60]Co [gamma] irradiation were the most significant in the parotid and the least in the sublingual gland. Also this reaction depended upon the doses of [sup 60]Co used. The present findings suggested that negative or weakened staining at the basal and perinuclear portions of striated duct cells specifically reflects the primary or secondary cell damage produced by [sup 60]Co [gamma] irradiation. Since the distribution of cytoskeletal proteins in the cytoplasm reflects certain pathological conditions, immunohistochemical detection of these proteins seem to have a diagnostic value with respect to cellular injury. (J.P.N.) 77 refs.

  6. Study on shelf life extension of papayas irradiated by /sup 60/Co gamma-rays

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    Chang, M.S.; Chen, M.D.; Lin, C.T.; Fu, Y.K.

    1984-11-01

    Papayas are one of the main fresh fruits in Taiwan area. Papaya fruits were treated with hot water to pasteurize peels followed by /sup 60/Co gamma-ray irradiation to extend the ripening time. The purpose of synergetic methods is to extend the shelf life of papaya fruits. This experiment was carried out by seven treatments, which were: (1) control group, (2) hot water treatment only, (3) hot water treatment with a 25 krad ..gamma..-irradiation, (4) hot water treatment with a 50 krad ..gamma..-irradiation, (5) hot water treatment with a 75 krad ..gamma..-irradiation, (6) 75 krad ..gamma..-irradiation only, and (7) hot water treatment with a 100 krad ..gamma..-irradiation. The items of observation were: surface yellowing, surface decaying, quality of texture, and length of period lasted after irradiation for 50% marketable papayas. The results of this study showed that a shelf-life extension of six days could be obtained for papayas subjected to hot water (50 to 55/sup 0/C) treatment and a 100 krad irradiation. 3 refs., 2 figs., 2 tabs.

  7. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

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    Lucas de Oliveira, P.C.; Madruga, R.A.; Barbosa, N.P.U. [Uberaba School of Veterinary Medicine (UNIUBE), MG (Brazil)]. E-mail: pedrolucaso@uol.com.br; Sakate, M. [UNESP, Botucatu, SP (Brazil). School of Veterinary Medicine and Animal Husbandry

    2007-07-01

    Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from {sup 60}Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca) venom, natural and irradiated from a {sup 60}Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5 mg/kg of natural venom; and GIIV, inoculated with 0.5 mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase, aspartate amino-transferase and alanine amino-transferase; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom. (author)

  8. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

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    P. C. Lucas de Oliveira

    2007-01-01

    Full Text Available Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from 60Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca venom, natural and irradiated from a 60Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5mg/kg of natural venom; and GIIV, inoculated with 0.5mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase (CK, aspartate amino-transferase (AST and alanine amino-transferase (ALT; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom.

  9. Study on Several Characteristics of Agaricus blazei Murril Strain J3 Irradiated by 60Co

    Institute of Scientific and Technical Information of China (English)

    WENG Bo-qi; JIANG Zhi-he; HUANG Ting-jun; CHEN Jian; ZHENG Wei-wen

    2003-01-01

    A new mutant strain J3 from Agaricus blazei Murril was obtained by 60Co irradiation. The yields of successive generations were increased more than 70% to compare with their original strain. The component analysis on amino acids and fatty acid illuminated that the nutrient value of strain J3 fruiting body was better than the original strain. The apparent nodule structure was found in the hyphea of J3 strain through the observation by scanning electron microscope. RAPD analysis showed the great difference of PCR fingerprints between J3 and its original strain. It is a promising mutant strain for further commercial development in the future.

  10. Seed germination of peanuts irradiated with cobalt ({sup 60}CO); Germinacao de sementes de amendoim irradiadas com cobalto ({sup 60}Co)

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    Alves, Niedja Marrize C.; Almeida, Francisco de Assis C.; Gomes, Josivanda P.; Pessoa, Elvira B., E-mail: niedjamarizze@yahoo.com.b, E-mail: josivanda@deag.ufcg.edu.b, E-mail: elvirabe@gmail.co [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia Agricola; Leal, Artur S. Cavalcanti, E-mail: arturcleal@yahoo.com.b [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia de Materiais

    2010-07-01

    This work was realized to evaluate the effect of gamma irradiation ({sup 60}Co) at doses 0, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00 and 4.00 kGy, on germination of seeds of peanut, cultivar BR1. Irradiation Department of Nuclear, UFPE, where he received after the irradiation, they were stored in packing of PET and polyethylene braided with a time of 90 days. Through the results, obtained monthly, concluded that the dose of 0.5 kGy was effective in the germination of seeds of peanut, not affecting its power of germination and overcoming the witness within 30 to 60 days. (author)

  11. Primary Observations on the Influence of 60Co Local Irradiation on Free Skin Flaps

    Institute of Scientific and Technical Information of China (English)

    杨建荣; 张园

    2002-01-01

    Objective To study the effect of postoperative radiation on free skin flaps.Methods Twenty-nine patients with free skin flaps applied to the plerosis of the postoperative defectwere followed up. Twenty-eight out of 29 patients received forearm free flaps while 1 had anterolater-al femoris skin flaps in a size ranging from 14 cm× 6 cm to 8 cm× 4 cm. These flaps were exposedto 60Co radiation ranging 40-69 Gy. Results Observation during irradiation: no visible changes ofskin flaps and oral mucous membrane were detected when irradiation dose was within 40 Gy; somechanges may be detected over 40 Gy. Observation 1 - 4 months after irradiation: pigmentations werefound in areas of erosion epidermis; skin flaps got dark but without evidence of necrosis. Observation2 years after irradiation: no necrosis happened in 29 skin flaps. Hairs were found on 15 of 29flaps. Sensation occurred within the margin of 1 cm. Conclusion Free skin flap can endure irradi-ation at the dose of 60 Gy.

  12. Grafting of HEMA onto dopamine coated stainless steel by 60Coirradiation method

    Science.gov (United States)

    Jin, Wanqin; Yang, Liming; Yang, Wei; Chen, Bin; Chen, Jie

    2014-12-01

    A novel method for grafting of 2-hydroxyethyl methacrylate (HEMA) onto the surface of stainless steel (SS) was explored by using 60Coirradiation. The surface of SS was modified by coating of dopamine before radiation grafting. The grafting reaction was performed in a simultaneous irradiation condition. The chemical structures change of the surface before and after grafting was demonstrated by Fourier transform infrared (FTIR) spectrometer. The hydrophilicity of the samples was determined by water contact angle measurement in the comparison of the stainless steel in the conditions of pristine, dopamine coated and HEMA grafted. Surface morphology of the samples was characterized by atomic force microscope (AFM) and scanning electron microscope (SEM). The corrosion resistance properties of the samples were evaluated by Tafel polarization curve. The hemocompatibility of the samples were tested by platelet adhesion assay.

  13. Gamma 60Co-irradiation of organic matter in the Phosphoria Retort Shale

    Science.gov (United States)

    Lewan, M. D.; Ulmishek, G. F.; Harrison, W.; Schreiner, F.

    1991-04-01

    Irradiation experiments were conducted on a thermally immature rock sample of the Phosphoria Retort Shale and its isolated kerogen. A 60Co-source for gamma radiation was employed at dosages ranging from 81 to 885 Mrads, which are attainable by Paleozoic and Precambrian black shales with syngenetic uranium enrichments. Kerogen elemental, isotopic, and pyrolysate compositions are not affected at these dosages, but the bitumens extracted from the irradiated rock are affected. The major effects are reductions in the amounts of bitumen, acyclic isoprenoids, and high-molecular weight acyclic carboxylic acids. Natural differences in the amounts of bitumen and acyclic isoprenoid due to regional and stratigraphie variations in organic source input and depositional conditions make the radiation-induced reductions in these parameters difficult to use as indicators of natural radiation damage in black shales. However, the preferential reduction in the high-molecular weight acyclic carboxylic acids, which are ubiquitous in the living precursory organic matter, is diagnostic of experimental γ-irradiation but may not be diagnostic of natural irradiation. The overall process associated with radiation damage is polymerization by cross-linking through a free radical mechanism. As a result, irradiation of organic matter in black shales is more likely to retard rather than enhance petroleum generation.

  14. Study of irradiated bothropstoxin-1 with {sup 60}Co gamma rays: immune system behavior

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    Caproni, P.; Baptista, J.A.; Almeida, T.L. de; Nascimento, N. [Nuclear and Energy Research Institute (IPEN/CNEN-SP), SP (Brazil). Biotechnology Center; Passos, L.A.C. [State University of Campinas (UNICAMP), SP (Brazil). Lab. of Genetics and Embryo Cryopreservation

    2009-07-01

    Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules. Very promising results were obtained when crude animal venoms, as well as isolated toxins, were treated with 60Co gamma rays, yielding toxoids with good immunogenicity. The achievement of modified antigens with lower toxicity and preserved or improved immunogenicity can be very useful. Ionizing radiation has already been proven to be a powerful tool to attenuate snake venom toxicity without affecting, and even increasing, their immunogenic properties. However, little is known about the modifications that irradiated molecules undergo and even less about the immunological response that such antigens elicit. In the present work, we investigated the immunological behavior of bothropstoxin-1, a K49 phospholipase, before and after irradiation. Structural modifications of the toxin were analyzed by SDS-PAGE. Isogenic mice were immunized with either the native or the irradiated toxin. The circulating antibodies were isotyped and titrated by ELISA. According to our data, irradiation promoted structural modifications in the toxin characterized by higher molecular weight forms of proteins (aggregates and oligomers). The results also indicated that irradiated toxins were immunogenic and antibodies elicited by them were able to recognize the native toxin in ELISA. These findings suggest that irradiation of toxic proteins can promote significant modifications in their structures; however they still retain many of the original antigenic and immunological properties of native proteins. Also, our data indicate that irradiated proteins induce higher titers of IgG2a and IgG2b, suggesting that Th1 cells are predominantly involved in the immune response. (author)

  15. Study of irradiated toxins with {sup 60}Co gamma rays: immune system behavior

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    Caproni, Priscila; Baptista, Janaina A.; Almeida, Tiago Luiz de; Passos, Luiz A.C.; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: pricaproni@hotmail.com

    2007-07-01

    Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules. Very promising results were obtained when crude animal venoms, as well as isolated toxins, were treated with {sup 60}Co gamma rays, yielding toxoids with good immunogenicity. The achievement of modified antigens with lower toxicity and preserved or improved immunogenicity can be useful. Ionizing radiation has been proven to be a powerful tool to attenuate snake venoms toxicity without affecting and even increasing their immunogenic properties. However, little is known about the modifications that irradiated molecules undergo and even less about the immunological response that such antigens elicit. In the present work, we have investigated the immunological behavior of bothropstoxin-I, a K49 phospholipase, before and after irradiation. Structural modifications of the toxin were investigated by SDS-PAGE. Isogenic mice were immunized with either the native or the irradiated toxin. The circulating antibodies were isotyped and titrated by ELISA. According to our data, irradiation promoted structural modifications in the toxin, characterized by higher molecular weight forms of the protein (aggregates and oligomers). Our data indicate that irradiated toxins were immunogenic and the antibodies elicited by them were able to recognize the native toxin in ELISA. These results indicate that irradiation of toxic proteins can promote significant modifications in their structures, but still retain many of the original antigenic and immunological properties of native proteins. Also, our data indicate that the irradiated protein induced higher titers of IgG2a and IgG2b, suggesting that Th1 cells were predominantly involved in the immune response. (author)

  16. Irradiation effect on enzymatic activity of papain with {sup 60}Co-{gamma} rays

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    Furuta, Masakazu; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio [Osaka Prefecture Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology

    1998-12-31

    An investigation was made on the durability of enzyme activity against {sup 60}Co-{gamma} irradiation at a dose up to 55 kGy/h using dry powder and aqueous solution of papain preparations on the market. Hybrid materials including bioactive molecules combined with biocompatible synthetic polymers are expected to have biocompatible properties and also biomimetic functions as a component of artificial organs for human body. The activity of papain in an aqueous solution was rapidly decreased at the early stage of irradiation through oxidation of SH group at its active site with active oxygen produced by the irradiation and then, partially recovered since SH group was reproduced in an anoxic state after O{sub 2} consumption in the solution irradiated at a high dose. A usual radiation method for sterilization was found applicable to decontamination of dry and frozen preparations of papain. When suitable conditions for radiation were chosen and N{sub 2} gas was purged to suppress the formation of free radicals, it was possible to keep the enzyme activity at more than 50% of the initial activity after radiation at 30 kGy. (M.N.)

  17. Evaluation of myotoxic activity of Bothropstoxin-1 irradiated with {sup 60}Co gamma rays

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    Mirco, Jessica; Baptista, Janaina A.; Caproni, Priscila; Yoshito, Daniele; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)], e-mail: jessica.mirco@yahoo.com.br, e-mail: janabap@gmail.com, e-mail: pricaproni@hotmail.com, e-mail: daniyoshito@uol.com.br, e-mail: nnascime@ipen.br

    2009-07-01

    Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules and has been proven to be a powerful tool to attenuate snake venoms toxicity without affecting their immunogenic properties. Snake venoms and their isolated toxins showed structural modifications after gamma radiation process, in aqueous solution, mainly by water radiolysis sub products. Free radical scavengers, such as NaNO{sub 3} and t-butanol, present selective effects on specific radical from water radiolysis. The NaNO{sub 3} has affinity by aqueous electron, while the t-butanol has affinity by hydroxyl radical. At the present work, we have investigated the myotoxic activity of Bothropstoxin-1 (BTHX-1), a K49 phospholipase, present in Bothrops jararacussu crude venom, before and after irradiation process, with or without scavenger substances presence. BTHX-1 was irradiated with 2 kGy of {sup 60}Co gamma rays, in aqueous solution and in the presence of oxygen. BALB/c mice were inoculated with either native or irradiated toxin, with or without scavenger substances. After 3 hours, blood samples were collected and the myotoxic activity was evaluated by LDH (lactate dehydrogenase) release. The muscular tissue damage was directly related to the LDH amounts released. Irradiated Bothropstoxin-1, with or without NaNO{sub 3} substance, caused less damage than their native counterpart. But irradiated toxin, in the presence of t-butanol, was so myotoxic as the native BTHX-1. These results indicate that irradiation of toxic proteins can promote significant modifications on their structures, but still retaining many of the original biological properties of their native counterparts. Additionally, some scavengers substances can change these gamma radiation effects. (author)

  18. Perna perna (LINNAEUS, 1758) mussels irradiated by {sup 60}CO gamma rays cytotoxicity evaluation

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    Martini, Gisela A.; Pusceddu, Fabio H.; Rogero, Sizue O.; Rogero, Jose Roberto, E-mail: gisela.martini@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The aim of the present work was the study of ionizing radiation effects on aquatic biota regarding the location of nuclear facilities nearby coastal areas assuming the risk of leaks and nuclear accidents. Bivalve mollusks have been widely used in the monitoring of aquatic environment studies mainly for their sessile habit and pollutants bioconcentration ability. So marine mussel Perna perna (Bivalvia: Mytilidae) was used as organism test in this study. The study of radioactive toxicity was performed by cytotoxicity test exposing the organisms to 11Gy gamma radiation dose. After radiation the neutral red retention assay evaluated the lysosomal membrane integrity in the mussel hemocytes. 50% lethal dose assay (LD50) of gamma radiation on Perna perna mussels was carried out by exposure the organisms to {sup 60}Co gamma rays at doses ranging from 0 to 3000 Gy. The result of gamma radiation LD50 for these mussels was 1068 Gy and the neutral red retention time of irradiated organisms was about 47% lower than the control, non irradiated organisms. With the obtained results is expected to contribute in the study to identify the range of ionizing radiation doses which can cause toxic effects in marine invertebrates. (author)

  19. Biochemical and pharmacological characterization of irradiated crotamine by gamma rays of {sup 60}Co; Caracterizacao bioquimica e farmacologica da crotamina irradiada por raios gama de {sup 60}Co

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    Oliveira, Karina Corleto

    2014-07-01

    The serum production in Brazil, the only effective treatment in cases of snakebites, uses horses that although large size, have reduced l lifespan compared with horses not immunized. Ionizing radiation has been shown as an excellent tool in reducing the toxicity of venoms and toxins isolated, and promote the achievement of better immunogens for serum production, and contributing to the welfare of serum-producing animals. It is known, however, that the effects of ionizing radiation on protein are characterized by various chemical modifications, such as fragmentation, cross-linking due to aggregation and oxidation products generated by water radiolysis. However, the action of gamma radiation on toxins is not yet fully understood structurally and pharmacologically, a fact that prevents the application of this methodology in the serum production process. So we proposed in this paper the characterization of crotamine, an important protein from the venom of Crotalus durissus terrificus species, irradiated with {sup 60}Co gamma rays. After isolating the toxin by chromatographic techniques and testing to prove the obtaining of pure crotamine, it was irradiated with gamma rays and subjected to structural analysis, Fluorescence and Circular Dichroism. Using high hydrostatic pressure tests were also conducted in order to verify that the conformational changes caused by radiation suffer modifications under high pressures. From the pharmacological point of view, muscle contraction tests were conducted with the objective of limiting the action of crotamine in smooth muscle as well as the change in the action of toxin caused structural changes to the front. Analysis of Circular Dichroism and Fluorescence showed changes in structural conformation of crotamine when subjected to gamma radiation and that such changes possibly occurring in the secondary and tertiary structure of the protein. The observed in pharmacological tests showed that the irradiated crotamine was less effective

  20. Effects of 2. 0 Gy of /sup 60/Co gamma rays irradiation on rat embryos

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    Lee, Juing-Yi; Satow, Yukio

    1987-01-01

    Pregnant rats of Donryu strain were exposed to a whole-body /sup 60/Co ..gamma.. ray irradiation of a single dose of 2.0 Gy (Dose rate: 0.5 Gy/min) on day 7, 8, 9, 10 or 11 of gestation (sperm day = day 0). The rats were sacrificed on day 18 and the offspring were examined for external and visceral malformations. Malformed embryos occurred between days 7 and 11 with the highest incidence occurring on day 9. Dose with 2.0 Gy increased the rate of resorption or death (52.1 %), in the survivors, caused congenital malformation in a majority of embryos (86.5 %) on day 8 of gestation. There is an increase in malformation (93.3 %) and growth retardation, but no increase in mortality (42.9 %) on day 9 of gestation. Relatively few anomalies resulted from irradiation on day 7 of gestation. The peak day for cardiovascular anomalies occurred on day 9 (88.3 % of all survival embryos) with high levels also occurring on day 8 (86.5 %). Cardiovascular anomalies consisted of VSD, hypoplasia of the pulmonary trunk, coarctation of the aorta, double aortic arch, right aortic arch, riding aorta, complete transposition of the aorta, persistent atrioventricular canal, vascular ring, aberrant right subclavian artery and others. Similar anomalies, but at a lower incidence, were produced by /sup 60/Co ..gamma.. ray at dose levels of 2.0 Gy on day 10 or 11 of gestation. Cases of cleft lip and cleft palate or facial cleft were observed seventeen fetuses on day 9 of gestation (31 %). Exencephaly occurred in nine embryos treated on day 9 (16.1 %) and in one embryos treated on day 10. Tail defects appeared with treatment on day 9 with the latter predominating on day 11. The present study show that maximum resorption (52.1 %) was seen with treatment on day 8 whereas the highest rate of malformation (93.3 %) was observed with treatment on day 9. (J.P.N.).

  1. Detection and thermoluminescence of coriander (Coriandrum sativum L.) irradiated with {sup 60}Co; Deteccion y termoluminiscencia del cilantro (Coriandrum sativum L.) irradiado con {sup 60}Co

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    Ruiz G, B. [Departamento de Agricultura y Ganaderia, Universidad de Sonora, 083190 Hermosillo, Sonora (Mexico); Cruz Z, E. [Unidad de Irradiacion y Seguridad Radiologica, Instituto de Ciencias Nucleares, UNAM, A. P. 70-543, 04510 Mexico D. F. (Mexico); Barboza F, M. [Centro de Investigacion en Fisica, Universidad de Sonora, A. P. 5-088, 083190 Hermosillo, Sonora (Mexico)

    2009-10-15

    The fresh and dried coriander (Coriandrum sativum L.) is a spice of high commercial value as food for consumption in Mexico. Their hygienic quality is often poor due to some factors: contaminants present in irrigation water and the cultivation atmosphere, harvesting and post harvest handling, mainly. The process by radiation is an alternative to achieve the sterilization to adequate dose for the hygienic quality for its consumption. However, irradiation also involves food detection exposed to radiation. This paper presents detected results on the dried coriander that was obtained from fresh samples and thermoluminescent properties such as glow curves structure from low doses (0.5 Gy) to high (15 kGy), the dose response, thermoluminescent signal decay, in order to determine the loss of stability during the storage of the poly mineral fraction. We obtained the inorganic fraction separation of the organic part of particle sizes of 10 {mu}m by the Zimmerman method. The samples were exposed at two dose ranges; 0.5-400 Gy and 0.5-15 kGy of gamma radiation with {sup 60}Co. The limit of thermoluminescent detection of the irradiated coriander samples was from 1 Gy. The glow curves were at a broad band of 35-400 C, with a maximum thermoluminescence around 182-196 C, and run at 164 C for high doses of 15 kGy. The range of linear response to dose was 4-25 Gy, whereas higher doses than the kGy order the response increase with the dose. The thermoluminescent properties of the coriander poly mineral fraction, show it can be used to identify irradiated food at gamma doses relatively low and even in doses of commercial interest due to the high stability of thermoluminescent signals. (Author)

  2. 60CoIrradiation Affects the Enzymatic Antioxidant System of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae

    Directory of Open Access Journals (Sweden)

    Ke Zhang

    2014-05-01

    Full Text Available Radio-(60Co, which emits γ rays, has been used worldwide in pest control. The aim of the present study was to analyze the effect of effective-low-power 60Coirradiation on the enzymatic antioxidant system of the citrus red mite Panonychus citri. One day old female adults were exposed to 0.4 kGy 60Coirradiation and on the, 6th h, 1st day, 2nd day, and 5th day post treatment, the mites were euthanized for biochemical analysis. The activity of superoxide dismutase (SOD, catalase (CAT, peroxidase (POD, phenoloxidase (PO and acetylocholinesterase (AchE were investigated. POD and CAT activities, as well as SOD were higher in the irradiated mites. We found that exposure to 60Co-γ radiation resulted in increased activities of SOD, CAT, POD and decreased AchE activity. When the recovery time lasted till the 5th day, the activities of POD and PO were significantly lower than the control, whereas the SOD, CAT and AchE activities returned to control levels. Cells possess protein repair pathways to rescue oxidized proteins and restore their functions, but if these repair processes fail, oxidized proteins may become cytotoxic. Our results confirm the hypothesis that low dosages of 60Coirradiation increase the level of oxidative stress in P. citri adults in a short time, causing meanwhile damage and sterility. The results of this study also indicate that stress caused by exposure to irradiation could inhibit the cholinergic system in P. citri.

  3. Viabilidade e micoflora de sementes de amendoim irradiadas com cobalto (60Co Viability and mycoflora of irradiated seeds of peanut with cobalt (60Co

    Directory of Open Access Journals (Sweden)

    Niédja M. C. Alves

    2011-03-01

    Full Text Available Estudou-se o efeito de diferentes doses da irradiação gama na germinação e percentagem de infecção fúngica em sementes de amendoim cultivar BR1. Inicialmente, as sementes foram avaliadas quanto à micoflora, utilizando-se o método de papel de filtro umedecido, a germinação em substrato de papel germitest e determinação do teor de umidade em estufa, a 105 ± 2 ºC. Posteriormente, as sementes foram submetidas à irradiação com uma fonte de 60Co, tipo gammacell, onde se estudou o efeito de 8 doses de irradiação na micoflora e germinação das sementes acondicionadas em embalagem de PET e polietileno trançado durante 60 dias de armazenamento, sem controle de temperatura e umidade relativa do ar. Os fatores estudados (doses em kGy, embalagens e tempo de armazenamento foram analisados em um delineamento inteiramente casualizado, dispostos em fatorial. Com base nos resultados, observou-se que a irradiação gama afetou negativamente a germinação das sementes de amendoim e que doses acima de 3,0 kGy comprometem a germinação das sementes. A radiação a partir da dose 1,5 kGy eliminou os fungos Aspergillus niger e, Penicillium a partir da dose de 2,5 kGy.The effect of different doses of the gamma irradiation was studied on germination and percentage of fungal infection in peanut seeds cultivar BR1. Initially the seeds were evaluated for the mycoflora using the method of humidified filter paper, the germination in paper substratum germitest and determination of the moisture content in oven at 105 ± 2 ºC. Later on the seeds were submitted to irradiation with a source of 60Co, type gammacell, where the effect was studied of 8 doses of irradiation in the mycoflora and germination of the seeds conditioned in PET packing and polyethylene tressed during 60 days of storage, without control of temperature and relative humidity of the air. The studied factors (doses in kGy, packing and time of storage were analyzed in a completely

  4. Manufacture of Single 60Co Source Irradiation Facility and the Measurement of Reference Radiation Filed

    Institute of Scientific and Technical Information of China (English)

    GAO; Fei; WANG; Hong-yu; NI; Ning; ZHANG; Li; HOU; Jin-bing; SONG; Ming-zhe

    2012-01-01

    <正>Reference radiation filed produced by isotope source is necessary for calibration of radiation dose meter. 60Co single source radiation facility is an important method to produce reference radiation. Collimation design of the facility is good for characteristics of the field, but there are scattered photon influences however. Scattered radiation is mainly come from collimation, source shield, floor, walls and

  5. Morphological and histological studies on freshwater prawn Macrobrachium rosenbergii (de man) irradiated with {sup 60}Co gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Stalin, A.; Broos, K.V. [P.G. and Research Department of Zoology, Jamal Mohamed College (Autonomous), Tiruchirappalli 620020, Tamil Nadu (India); Sadiq Bukhari, A., E-mail: abjmc@yahoo.in [P.G. and Research Department of Zoology, Jamal Mohamed College (Autonomous), Tiruchirappalli 620020, Tamil Nadu (India); Syed Mohamed, H.E. [P.G. and Research Department of Zoology, Jamal Mohamed College (Autonomous), Tiruchirappalli 620020, Tamil Nadu (India); Singhal, R.K. [Analytical Spectroscopy Section, Analytical Chemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 4000085 (India); Venu-Babu, P. [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Center, Trombay, Mumbai 4000085 (India)

    2013-11-15

    Graphical abstract: -- Highlights: •Analyzing the impact of {sup 60}Co gamma radiation (low doses) in M. rosenbergii. •LD{sub 50} identified in 30 Gy; Irradiated exhibits morphological changes than control. •Significantly decreased HSI and histological changes in irradiated groups. •Aberration severities increased as increased of dose level. •Biomonitoring tool in determining low dose radiation pollution in aquatic ecosystem. -- Abstract: This study was framed to investigate the {sup 60}Co gamma radiation induced morphological and histological variations in freshwater prawn Macrobrachium rosenbergii. The LD{sub 50} value of {sup 60}Co gamma irradiated M. rosenbergii observed (by probit analysis) at 30 Gy. Prawns were irradiated to four different dose levels (3 mGy, 30 mGy, 300 mGy and 3000 mGy) using Theratron Phoenix TeleCobalt Unit [P-33] and one control group (without irradiation) maintained separately. Irradiated groups exhibited several morphological variations such as discoloration; damaged rostrum; opaque coloration in cephalothorax; black bands and dot formation in abdomen; deformed uropods and telson in tail regions when compared with control group. The Hepato Somatic Index reflected the severity of radiation on hepatopancreas. Histological variations in gills, hepatopancreas and muscles of irradiated groups were observed. In gills, structural changes such as swollen and fused lamellae, abnormal gill tips, hyperplasic, necrotic and clavate-globate lamellae were observed in gamma irradiated prawns. Accumulation of hemocytes in hemocoelic space, interstitial sinuses filled with abnormal infiltrated hemocytes, the tubular epithelium with ruptured basal laminae, abnormal and coagulated lumen, necrotic tubules, thickened basal laminae, tissue debris, necrotic hepatocytes were observed in irradiated prawn hepatopancreas. In muscle, shrinkage of muscular fiber and necrotic musculature were observed in irradiated prawns. These structural alterations of

  6. Morphological and histological studies on freshwater prawn Macrobrachium rosenbergii (de man) irradiated with (60)Co gamma radiation.

    Science.gov (United States)

    Stalin, A; Broos, K V; Sadiq Bukhari, A; Syed Mohamed, H E; Singhal, R K; Venu-Babu, P

    2013-11-15

    This study was framed to investigate the (60)Co gamma radiation induced morphological and histological variations in freshwater prawn Macrobrachium rosenbergii. The LD50 value of (60)Co gamma irradiated M. rosenbergii observed (by probit analysis) at 30 Gy. Prawns were irradiated to four different dose levels (3 mGy, 30 mGy, 300 mGy and 3,000 mGy) using Theratron Phoenix TeleCobalt Unit [P-33] and one control group (without irradiation) maintained separately. Irradiated groups exhibited several morphological variations such as discoloration; damaged rostrum; opaque coloration in cephalothorax; black bands and dot formation in abdomen; deformed uropods and telson in tail regions when compared with control group. The Hepato Somatic Index reflected the severity of radiation on hepatopancreas. Histological variations in gills, hepatopancreas and muscles of irradiated groups were observed. In gills, structural changes such as swollen and fused lamellae, abnormal gill tips, hyperplasic, necrotic and clavate-globate lamellae were observed in gamma irradiated prawns. Accumulation of hemocytes in hemocoelic space, interstitial sinuses filled with abnormal infiltrated hemocytes, the tubular epithelium with ruptured basal laminae, abnormal and coagulated lumen, necrotic tubules, thickened basal laminae, tissue debris, necrotic hepatocytes were observed in irradiated prawn hepatopancreas. In muscle, shrinkage of muscular fiber and necrotic musculature were observed in irradiated prawns. These structural alterations of the organs it is felt could affect the vital physiological functions such as respiration, osmotic and ionic regulation in gills and muscles; absorption, storage and secretion of the hepatopancreas which in turn could adversely affect the growth and survival of freshwater prawn M. rosenbergii.

  7. Dose intercomparison studies for 60Co gamma-ray and electron beam irradiation in the year 2002

    Institute of Scientific and Technical Information of China (English)

    LIN Min; Takuji KOJIMA; Zofia PEIMEL-STUGLIK; CHEN Yun-Dong; CUI Ying; CHEN Ke-Sheng; LI Hua-Zhi; XIAO Zhen-Hong; Slawomir FABISIAK

    2004-01-01

    Dose inter-comparison studies for 60Co γ-ray and 10MeV electron beam irradiation were carried out from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosimeters made by CIAE, which will be used as transfer standard dosimetry system mainly for electron beam irradiation.The expanded uncertainty of CIAE alanine/EPR dosimetry system was 4.1% for doses not higher than 10 kGy and 5.4% for those above 10 kGy (k=2). CIAE alanine-PE film dosimeters were sent to JAERI, RISO (National Laboratory in Denmark) and INCT respectively, which were irradiated by 60Co gamma-rays or electron beams in each laboratory. The irradiated dosimeters were then sent back to CIAE for electron paramagnetic resonance (EPR) analysis.The agreements were obtained to be ±1.9% for gamma-ray dose measurement and ±4.3% for electron beam dose measurement, which were all within the combined uncertainty of the reference and CIAE alanine/EPR dosimetry system. Furthermore, the overall mean ratio was found to be 0.995 with 1.8% in the coefficient of variation (CV). The preliminary inter-comparison studies indicated that CIAE film alanine/EPR dosimetry system had the potential to be used as a transfer dosimetry system for high dose measurement.

  8. Effects of (60)Co gamma irradiation on behavior and gill histoarchitecture of giant fresh water prawn Macrobrachium rosenbergii (DE MAN).

    Science.gov (United States)

    Stalin, A; Broos, K V; Sadiq Bukhari, A; Syed Mohamed, H E; Singhal, R K; Venu-babu, P

    2013-06-01

    Present study was designed to observe the effects of (60)Co gamma radiation in behavioral and histological changes in the gills of giant fresh water prawn Macrobrachium rosenbergii. The adult prawns were irradiated with four different dose levels (3mGy, 30mGy, 300mGy and 3000mGy) and the control group (without irradiation) was maintained separately. Behavioral changes like hyperactivity, loss of balance, reduced swimming rate, slower rate of food intake and convulsions were observed in higher dose levels of 300mGy and 3000mGy. The histological alterations such as accumulated haemocytes in haemocoelic spaces, abnormal gill tips, lifted lamellar epithelium, swollen and fused lamellae, hyperplasic, necrotic, clavate-globate and complete disorganization of lamellae were observed in (60)Co gamma irradiated prawns. Significantly more considerable histological alterations were observed in the highest dose level of 3000mGy, but no mortality was evidenced. This study serves as biomonitoring tool to assess the radiation pollution in the aquatic environment.

  9. Humoral immune response against native or {sup 60}Co irradiated venom and mucus from stingray Paratrygon aiereba

    Energy Technology Data Exchange (ETDEWEB)

    Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Aires, Raquel da Silva; Turibio, Thompson de Oliveira; Rocha, Andre Moreira; Spencer, Patrick Jack; Nascimento, Nanci do, E-mail: 0916@prof.itpacporto.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Seibert, Carla Simone, E-mail: carlaseibert@yahoo.com [Universidade Federal do Tocantins (UFT), Porto Nacional, TO (Brazil)

    2015-07-01

    Poisonings and traumas caused by poisonous freshwater fish such as rays are considered a major public health problem and draw attention because of accidents involving these animals cause serious local symptoms and are disabling, keeping the victim away from work. The therapy of these cases is based only on the symptoms of patients, which implies in its low efficiency, causing suffering for the victims. This study aims to evaluate and compare the humoral immune response in animals inoculated with native or {sup 60}Co irradiated Paratrygon aiereba venom and mucus. Ionizing radiation has proven to be an excellent tool to decrease the toxicity of venoms and isolated toxins. The mucus and venom samples of P. aiereba were irradiated using gamma rays from a {sup 60}Co source. Animals models were immunized with the native or irradiated mucus or venom. The assays were conducted to assess the production of antibodies by the immunized animals using enzyme immunoassay and western blotting. Preliminary results show the production of antibodies by the immunized animals. The resulting sera were also checked for antigenic cross- reactivity between venom and mucus, demonstrating the potential of mucus as an antigen for serum production for the specific treatment for accidents by stingrays. However, it is essential to carry out further tests in order to verify the neutralization of the toxin by antibodies formed by animals. (author)

  10. 60Co γ辐照对西红花发育的影响%EFFECTS OF 60 Co γ-IRRADIATION ON DEVELOPMENT OF Crocus sativus L

    Institute of Scientific and Technical Information of China (English)

    赵军; 陈晓斌; 陈放

    2006-01-01

    本文利用剂量为5~25Gy的60Co γ射线,对重12~14g的西红花球茎进行辐照处理,研究辐照对西红花开花、花器官发育和球茎再生等方面的影响.结果显示:辐照处理对西红花开花有刺激作用;5~10Gy为西红花的最适诱变剂量.

  11. Modifications in structural, cation distribution and magnetic properties of {sup 60}Co gamma irradiated Li-ferrite

    Energy Technology Data Exchange (ETDEWEB)

    Mane, Maheshkumar L. [Department of Physics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad (M.S.) 431 004 (India); Shirsath, Sagar E., E-mail: shirsathsagar@hotmail.com [Department of Physics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad (M.S.) 431 004 (India); Dhage, Vinod N.; Jadhav, K.M. [Department of Physics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad (M.S.) 431 004 (India)

    2011-09-15

    Highlights: {yields} Gamma irradiation induced defects in lithium ferrite. {yields} Modifications in structural and magnetic properties. {yields} Fe{sup 3+} changes to Fe{sup 2+} after gamma irradiation. - Abstract: Polycrystalline samples of Li{sub 0.5}Fe{sub 2.5}O{sub 4} ferrite precursor were prepared by conventional standard double sintering ceramic technique and then irradiated with three different doses of {sup 60}Co gamma rays. The crystal structure and phase orientation of the irradiated and unirradiated samples of Li{sub 0.5}Fe{sub 2.5}O{sub 4} ferrite was done by using X-ray diffraction technique at room temperature. The lattice parameter of the studied samples increased due to the formation of Fe{sup 2+} ions under the ionizing effect of gamma radiation. The strain in the materials due to the irradiation was calculated from XRD data. Scanning electron microscope (SEM) studies indicate that the irradiation causes amorphization, especially at the grain boundaries. The cation distribution was calculated from XRD data analysis. By using cation distribution structural parameters such as theoretical lattice constant, ionic radii of available sites and the oxygen parameter 'u' have been calculated. The estimated cation distribution and other structural parameters shows strong influence of gamma rays on polycrystalline Li-ferrite. The magnetic properties of irradiated and unirradiated lithium ferrite were performed by using pulse field hysteresis loop technique at room temperature. Electrical properties such as diffusion coefficient and dielectric properties were carried out with the influence of gamma irradiation. Activation energy of diffusion process decreased after irradiation. The increase of diffusion coefficient with increasing dose rate of gamma irradiation was reinforced by the increase of Fe{sup 2+} ions and the displacement of metal ions from its original sites under the effect of gamma irradiation.

  12. Effects of /sup 60/Co-. gamma. irradiation on the cell proliferation kinetics of DMBA-induced tongue carcinoma in hamster

    Energy Technology Data Exchange (ETDEWEB)

    Wada, Toshio

    1987-10-01

    In the vocation of the radiation therapy, it is very important to analize the cell kinetics of the normal and tumor tissues, and the radiation effects. Thus, this study analizes the effects of /sup 60/Co-..gamma.. irradiation to DMBA-induced hamster tongue carcinoma (hereafter ''the tumor'') and normal tongue epithelium (hereafter ''the normal'') by using /sup 3/H-TdR puls labeling technics and percentage labeled mitoses (PLM) method. Result : 1) Cell cycle time (Tc) of the Normal was 42.0 hours, and that of the tumor was 18.1 hours. After irradiation, Tc of the tumor was prolonged, but that of the normal was shortened by about 11 hours. 2) Initial labeling index (L.I.) of the tumor was decreased immidiately after irradiation, but on 7 and 10 days L.I. gained back to the pre-irradiation rate. 3) tumor doubling time (Td) was 6.4 +- 1.6 days, and potential doubling time (Tp) was 18.9 hours. 4) Time of pre-DNA synthetic stage (Tg/sub 1/) of the normal was 31.0 hours and that of the tumor was 8.7 hours. After irradiation, Tg/sub 1/ of the normal was shortened by about 10 hours and that of the tumor was prolonged. 5) After irradiation, time of synthetic stage (Ts) of both the normal and the tumor was slightly prolonged. 6) After irradiation, mitotic stage (Tm) of both the normal and the tumor was not changed. 7) Growth fraction (GF) of the normal was 64.5%, and that of the tumor was 79.8%. After irradiation, it was decreased, while it of the tumor was increased temporarily after irradiation. 8) The rate of cell loss facter of the tumor was 0.88.

  13. Immune response against bothropstoxin-I irradiated with {sup 60}Co gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, J.A.; Spencer, P.J.; Higa, O.Z.; Casare, M.S.; Campos, L.A.; Nascimento, N. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Biologia Molecular]. E-mail: janabap@gmail.com; Andrade Junior, H.F de [Sao Paulo Univ., SP (Brazil). Inst. de Medicina Tropical de Sao Paulo. Lab. de Protozoologia]. E-mail: hfandrad@usp.br

    2005-07-01

    Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules. Very promising results were obtained when crude animal venoms, as well as isolated toxins, were treated with gamma rays, yielding toxoids with good immunogenicity. Ionizing radiation has proven to be a powerful tool to attenuate snake venoms toxicity without affecting and even increasing their immunogenic properties. However, little is known about the modifications that irradiated molecules undergo and even less about the immunological response that such antigens elicit. In the present work, we investigated the immunological behavior of bothropstoxin-I, a K49 phospholipase, before and after irradiation. Structural modifications of the toxin were investigated by SDS-PAGE and mass spectrometry. Aiming to compare the toxicity between native and irradiated forms of the toxin, an in vitro cytotoxicity assay, using CHO cells, was performed. Isogenic mice were immunized with either the native or the irradiated toxin. The circulating antibodies were isotyped and titrated by ELISA. According to our data, irradiation promoted structural modifications in the toxin, characterized by higher molecular weight forms of the protein (aggregates and oligomers). When analyzed by mass spectrometry, the irradiated bothropstoxin appeared in several oxidized forms. The cytotoxicity assay showed that the modified toxin was 5 folds less toxic than its native counterpart. Irradiated toxins were immunogenic and the antibodies elicited by them were able to recognize the native toxin in ELISA. These results indicate that irradiation of toxic proteins can promote significant modifications in their structures, but still retain many of the original immunological properties. (author)

  14. Structure alteration and immunological properties of {sup 60}Co gamma rays irradiated bothropstoxin-I

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Janaina A.; Yonamine, Camila Myiagui; Caproni, Priscila; Casare, Murilo; Spencer, Patrick Jack; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: janabap@gmail.com; Andrade Junior, Heitor Franco de; Vieira, Daniel Perez; Galisteo Junior, Andres Jimenez [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Instituto de Medicina Tropical de Sao Paulo, SP (Brazil). Lab. de Protozoologia

    2007-07-01

    About 20000 ophidic accidents are registered every year in Brazil. Serum therapy with equine antisera is the only efficient treatment. The venoms employed for immunization are fairly toxic and some venoms present low immunogenicity. Thus, the obtention of modified antigens with lower toxicity and preserved or improved immunogenicity would be useful. These toxins, when submitted to gamma radiation, in aqueous solution, present structural modifications. This occurs due to reactions with the radiolysis products of water. Some scavenger substances, such as NaNO{sub 3} and t-butanol, remove selectively the water radiolysis products. Ionizing radiation has proven to be a powerful tool to attenuate snake venoms toxicity without affecting and even increasing their immunogenic properties. However, the immune mechanisms involved in recognition, processing and presentation of irradiated antigens are yet unclear. In the present work, we investigated the immunological behavior of bothropstoxin-I (Bthx-1), before and after irradiation, in the presence of selective scavengers. Isogenic mice were immunized with either the native or the irradiated toxin, either with or without scavengers. After three immunizations, serum samples were collected and the antibody titers and isotypes were determined by Enzyme Linked Immuno Sorbent Assay. The antigenic characterization of native and irradiated bothropstoxin-I was performed by Western blot. The detection of expression of murine cytokines (IFN-{gamma} and IL-10) was analyzed by RT-PCR (Reverse Transcriptase-Polymerase Chain Reaction). According to our data, irradiation process has promoted structural modifications in the toxin, characterized by higher molecular weight forms of the protein (aggregates and oligomers). Our data also indicate that irradiated toxins, alone or in the presence of NaNO{sub 3}, an aqueous electron scavenger, were immunogenic and the antibodies elicited by them were able to recognize the native toxin. On the other

  15. {sup 60}Co irradiation effect on color in minimally processed cauliflower (Brassica spp)

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Santillo, Amanda G.; Villavicencio, Anna L.C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: thaisecfnunes@hotmail.com; Michels, Robert [Hydrofarm Comercio e Representacao de Produtos Agricolas Ltda., Sao Roque, SP (Brazil); Pitombo, Ronaldo N.M. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Alimentos e Nutricao Experimental

    2009-07-01

    Irradiation is a well-established process with clearly documented safety and efficacy. Consumers require a quality product that is convenient and has fresh-like characteristics and take product appearance, like color, into consideration as a primary criterion; it is considered a key role in food choice, food preference and acceptability. The objective of the present work was to investigate color degradation of cauliflower treated with gamma radiation during 14 days. Cauliflower irradiated samples with 0 and 1.5 kGy showed significant differences for value 'L' on the 10th and 14th day, respectively for value 'b' only the 0 kGy sample showed significant difference on day 10 of storage. On day 10 of shelf-life the irradiated cauliflower with doses of 1 and 1.5 kGy became more yellow compared to the control. The authors concluded that the treatment with low gamma radiation doses keeps the quality of fresh-cut vegetables. (author)

  16. Response of S. boulardii cells to {sup 60} Co irradiation and heat shock

    Energy Technology Data Exchange (ETDEWEB)

    Neves, M.J.; Andrade, A.S.R.; Santos, R.G. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Nicoli, J.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. Microbiologia

    1997-12-31

    Full text. Preparation of Saccharomyces boulardii, a non pathogenic yeast, has been widely used in Europe and other countries to prevent gastrointestinal disorders. However the mechanism of action of theses cells on the illness is unknown but the efficacy of S. boulardii depends on its viability. As trehalose is a well known viability protectant in yeast cells against several adverse conditions, we determined its level. We measured the level of trehalose in cells submitted to heat shock, gamma irradiation and simulation of gastric environmental, all these conditions are commonly found during the bio therapeutic production and in the patients oral treatment. Trehalose levels were higher in yeast cells surviving to gamma irradiation ({sup 60} Cobalt) than in control cells. S. boulardii cells growth in log phase and submitted to the heat shock (40 deg C). Accumulated more trehalose than S. cerevisiae and unlikely to these cells, the pool of trehalose accumulated in S. boulardii was mobilized very slowly (70% of the trehalose pool was present 5 hours after the return to the normal temperature 30 deg C). Our results suggested a rather different trehalose metabolism in S. boulardii when compared with S. cerevisiae and showed that one of the response to the stress of irradiation was an increasing on the level of intracellular trehalose

  17. Effect of 60Co gamma irradiation on dielectric and complex impedance properties of Dy3+ substituted Ni-Zn nanoferrites

    Science.gov (United States)

    Veena, M.; Somashekarappa, A.; Shankaramurthy, G. J.; Jayanna, H. S.; Somashekarappa, H. M.

    2016-12-01

    Nanocrystalline Ni1-xZnxFe2-yDyyO4 (x=0.0, 0.2, 0.4, 0.6, 0.8, 1.0; y=0.0 and 0.1) ferrites were synthesized by combustion method. Ni-Zn-Dy nanoferrites were investigated by X-ray diffraction, scanning electron microscopy, dielectric and impedance properties, before and after γ-irradiation process by 60Co γ-radiation with a dose rate of 310 kGy. The lattice parameter of irradiated samples increased attributed to the conversion of smaller size Fe3+ ions to larger size Fe2+ ions on ionizing effect of gamma radiation. Experimental results reveal that reduction in dielectric constant (ε‧), loss tangent (tan δ), real (Z‧) and imaginary (Z‧‧) impedance and increase in ac conductivity (σac) have been increased with increasing in frequency. It was found that ε‧, tan δ, σac increase, Z‧‧ and Z‧‧ reach a maximum value and thereafter decrease with further Zn ion substitution. The values of ε‧, tan δ and σac decrease with Dy3+ substitution and enhanced after irradiation. The complex impedance analysis suggesting predominant contribution to conduction was through the grain boundary.

  18. Paramecium tetraurelia growth stimulation under low-level chronic irradiation: investigations on a possible mechanism. [/sup 60/Co

    Energy Technology Data Exchange (ETDEWEB)

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H.

    1982-12-01

    Experiments were carried out to demonstrate the effects of low-level chronic irradiation on Paramecium tetraurelia proliferation. Biological effects were strongly dependent on the bacterial density of culture medium and more exactly on the catalase content of the medium. Significant growth stimulation was found under /sup 60/Co chronic irradiation at a dose rate of 2 rad/year when paramecia were grown in a medium containing a high bacterial concentration (2.5 x 10/sup 2/ cells/m) or supplemented with catalase (300 U/ml). In a medium with a low bacterial density (1 x 10/sup 6/ cell/ml) or supplemented with a catalase activity inhibitor, growth simulation was preceded by a transitory inhibiting effect which could be correlated with extracellularly radioproduced H/sub 2/O/sub 2/. H/sub 2/O/sub 2/ addition appeared to be able to simulate the biological effects of chronic irradiation. A possible mechanism is discussed.We proposed that the stimulating effects were the result of intracellular enzymatic scavenging of radioproduced H/sub 2/O/sub 2/.

  19. 60Coγ射线损伤后小鼠造血系统生理指标的动态变化%Changes of Physiological Indexes in Hematopoietic System of Mice after 60Coγ Ray Irradiation

    Institute of Scientific and Technical Information of China (English)

    侯新然; 王晓波; 袭荣刚; 李忠亮; 高慧媛; 吴立军; 马晓梅

    2012-01-01

    Objective To explore the physiological variation of the hematopoietic system in mice after C07 ray irradiation. Methods Body weight, peripheral blood cell counts,the immune organ index and pathological changes in femoral bone marrow of mice were measured at different times after whole-body irradiation with C07 ray. The doses were 2,4,6 Gy respectively. Results The changes of peripheral blood of mice were different. The white blood cell counts declined most rapidly and obviously,followed by the platelet count,with a dose-effect relationship. Three days after radiation, the immune organ index of mice decreased significantly compared with the immune organ index in mice unirradiated. Myeloid elements in bone marrow were reduced and bone marrow hematopoiesis was depressed. Body weight of irradiated mice grew slowly, without significant difference with mice unirradiated. Conclusion 60Coγ ray radiation can decrease peripheral blood cells, decrease the immune organ index and inhibit bone marrow cell proliferation in mice.%目的 探索小鼠60Coγ射线损伤后造血系统各项生理指标的变化规律.方法 采用60Coγ射线对小鼠进行一次性全身照射,剂量分别为2、4、6 Gy,在不同时间分别测定小鼠体质量,外周血细胞计数,免疫器官指数及股骨骨髓的病理变化.结果 照射后小鼠的外周血象有变化,其中白细胞下降最迅速且明显,其次是血小板,且具有剂量效应关系.照射后3d免疫器官指数下降明显,与对照组比较具有显著性差异;骨髓造血细胞数目迅速减少,出现造血抑制;照射后小鼠体质量增加缓慢,但与对照组比较无显著性差异.结论 60Coγ射线照射可引起小鼠外周血细胞下降,免疫器官指数下降,并抑制骨髓造血细胞增生.

  20. Evaluation by EPR of potential antioxidant components of {sup 60}Co-irradiated varieties of soybean; Avaliacao por RPE de componentes com potencial antioxidante de variedades de soja irradiadas com {sup 60}CO

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcos Ronaldo Ramos de

    2009-07-01

    Brazil is today the second main producer of soybean in the world with a planted ground of about 21 million hectares and an annual production of 60 million tons in 2008, being slight more than a fourth of the annual production. The presence of flavonoids, particularly isoflavones in soybean products has been related as important for human health. It has been suggested that flavonoids play a role in the protection of plants by screening vital cellular components from damaging UV radiation. Electron paramagnetic resonance (EPR) spectroscopy can measure free radicals produced by dissociation molecules resulting from irradiation. It has been successfully employed for the detection of some irradiated food products. Twenty one Brazilian soybean cultivars from two crops were gamma-irradiated with a {sup 60}Co source and evaluated by EPR. Correlation coefficients were made among the central EPR signal (g = 2.0039) and the total and partial isoflavones contents. There was no correlation with total contents, though glicitein and acetyl-daidzin showed a negative correlation. Even 7 months after irradiation the intensity of central EPR signal were high enough to distinguish the irradiated samples. EPR measurements of separated parts of the grain were more efficient for that purpose, particularly from hilum and coat. The radiation did not change substantially the total isoflavone contents, although there were some evidences suggesting some conversion of glycosides to aglycones. (author)

  1. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of {sup 60}Co; Estudo bioquimico e farmacologico das crotaminas nativa e irradiada com radiacao gama de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Mitake, Malvina Boni

    2000-07-01

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide from the South American rattlesnake venom, composed of 42 amino acid residues. It induces skeletal muscle spasms leading to a spastic paralysis of hind limbs in mice. The objective of this thesis was carry out biochemical and pharmacological studies of native and irradiated crotamine with {sup 60} Co. Crotamine was purified from Crotalus durissus terrificus venom by Sephadex G-100 gel filtration followed by ion exchange chromatography, using a Fast Performance Liquid Chromatography (FPLC) system. It was irradiated at 2 mg/ml in 0.15 M Na Cl with 2.0 kGy gamma radiation emitted by a {sup 60} Co source. The native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD{sub 50} and biodistribution. The native and irradiated crotamine were labelled with 29.6 MBq of {sup 125} I using chloramine T method, and separated in a Sephadex G-50 column. Male Swiss mice (35{+-} 5 g), were injected i.p. with o.1 mL (2.4 x 10{sup 6} cpm/mouse) of {sup 125} I native crotamine or with 0.4 mL (1.3 x 10{sup 6} cpm/mouse) of {sup 125} I irradiated crotamine. At 0.08; 0.25; 0.5; 1; 2; 4; 8; 12 and 24 hours the animal were killed by ether inhalation. Blood, spleen, liver, kidneys, brain, lungs, heart, and skeletal muscle were collected in order to determine radioactivity content. The results showed that gamma radiation did not change the protein concentration, the electroforetic profile or the primary structure of the protein, although differences were shown by spectroscopic techniques. The gamma radiation diminished the toxicity of crotamine, but it did not abolish bioactivity. Biodistribution studies showed that native and irradiated crotamine have hepatic metabolism and renal elimination. The native and irradiated crotamine have affinity by skeletal

  2. 白藜芦醇对60Coγ射线照射小鼠氧化损伤的防护%Radioprotective Effect of Resveratrol on Oxidative Damage in 60Co Gamma Ray Irradiated Mice

    Institute of Scientific and Technical Information of China (English)

    徐冰心; 李成林; 史煜华; 谢京波; 陈阿鑫; 高娇; 任晔; 李建忠; 刘志国

    2012-01-01

    Objective To investigate the radioprotective effect of resveratrol( RES) on gamma-irradiation-induced serum and liver oxidative damage in mice. Methods Thirty male ICR mice were randomized into 5 groups; normal control group, irradiated control group, RES 50,100 and 200 mg·kg-1 irradiated groups. RES was administered respectively to three dosage groups by gavage on 3rd day before irradiation and 7th day after irradiation. Except for normal control, all the mice were whole-body irradiated by 60Co gamma ray(a single dose of 6.0 Gy). The mice were killed on 7th day. The activities of superoxide dismutase (SOD) ,glutathione peroxidase (GSh-Px) and the amount of malondialdehyde( MDA) of the serum and liver were measured. Results Compared with normal control group,the activities of SOD and GSH-Px were significantly decreased while the amount of MDA was significantly increased in irradiated control group mice. Compared with irradiated control, the activities of SOD and GSH-Px tended to increase while the amount of MDA tended to decrease in RES 50 mg ·kg-1' irradiated group mice. The activities of SOD and GSh-Px and the amount of MDA increased with the RES dosage. Conclusion RES has radioprotective effect against oxidative damage to the serum and liver in 60Co rays irradiated mice. This effect of RES depends on the dosage.%目的 研究白藜芦醇对60Coγ射线照射小鼠氧化损伤的防护作用.方法 30只♂ ICR小鼠随机分成5组,正常对照组、照射对照组以及白藜芦醇低、中、高剂量( 50、100、200 mg·kg-1)照射组,照射前3d至照后第7天灌服给药,每天1次,共10次.除正常对照组外,所有小鼠60Coγ射线全身6 Gy辐照1次,照射后第7天小鼠取外周血和肝组织标本,测定血清和肝组织匀浆中超氧化物歧化酶(SOD)、谷胱苷肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量.结果与正常对照组比较,照射对照组小鼠血清和肝组织匀浆中SOD和GSH-Px活性显著下降,MDA含量显

  3. Numerical simulation of 60Co-gamma irradiation effects on electrical characteristics of n-type FZ silicon X-ray detectors

    Science.gov (United States)

    Vigneshwara Raja, P.; Rao, C. V. S.; Narasimha Murty, N. V. L.

    2016-07-01

    This paper describes the gamma irradiation effects on the electrical characteristics of n-type float zone (FZ) silicon detectors by incorporating a 4-level 60Co-gamma radiation damage model in the commercial device simulator for plasma X-ray tomography diagnostics. In the simulations, a segmented n-type silicon detector (i.e. p+-n-n+ structure) is considered with varying substrate resistivity (ρ = 5.4, 2.5, and 0.3 kΩ cm). The simulation results have been validated with the reported experimental measurements carried out on similar device structures. The 60Co-gamma irradiation induced changes in the electrical characteristics of the detectors are analyzed up to the dose of 3500 Mrad. The possible gamma induced degradation in the X-ray response of the detectors is investigated from the changes in the effective doping concentration and the leakage current of the detectors. The survival of the gamma irradiated detectors is predicted from the simulation studies. The comparison between the 60Co-gamma and 14.1 MeV neutron irradiation effects (typical fusion environments) on silicon detectors is attempted.

  4. Transfection of p27 kip1 enhances radiosensitivity induced by 60Coγ-irradiation in hepatocellular carcinoma HepG2 cell line

    Institute of Scientific and Technical Information of China (English)

    Xiao-Xiang Guan; Long-Bang Chen; Gui-Xia Ding; Wei De; Ai-Hua Zhang

    2004-01-01

    AIM: To study the cell cycle alterations of human hepatoma cell line HepG2 in vitro after 60Co γ-irradiation and further to examine the mechanisms underlying the enhancement of radiosensitivity to γ-irradiation in HepG2 transiently transfected with wild type p27kip1.METHODS: The proliferation of HepG2 cells was evaluated with MTT assay, and the cell cycle profile and apoptosis were assessed by cell morphology, DNA fragmentation analysis and flow cytometry. HepG2 cells were transfected with p27kip1 wild type by using Lipofectamine (LF2000), and the expression and subcellular localization of p27kip1 in HepG2were detected by immunocytochemistry.RESULTS: 60Co γ-irradiation inhibited the growth of HepG2cells in a dose-dependent manner. Apoptosis of HepG2 cells was induced 48 h after γ ray exposure. Furthermore research was carried out to induce exogenous expression of p27kip1in HepG2. The expression of p27kip1 induced G0/G1 phase arrest in HepG2 cells. The overexpression of p27kip1 enhanced 60Co γ-irradiation-induced radiosensitivity in HepG2 cells.CONCLUSION: Overexpression of p27kip1 is a rational approach to improve conventional radiotherapy outcomes, which may be a possible strategy for human hepatoma therapy.

  5. Analysis of the frequency of unstable chromosome aberrations in human lymphocytes irradiated with {sup 60}Co; Analise da frequencia de alteracoes cromossomicas instaveis em linfocitos humanos irradiados com {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, Julyanne C.G.; Mendes, Mariana E.; Lima, Fabiana F., E-mail: july_cgm@hotmail.com, E-mail: mendes_sb@hotmail.com [Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Santos, Neide, E-mail: santos_neide@yahoo.com.br [Universidade Federal de Pernambuco (CCB/UFPE), Recife, PE (Brazil). Departamento de Genetica

    2013-07-01

    The aim of this study was to analyze the frequency of unstable chromosomal aberrations induced by gamma radiation from a {sup 60}Co source at two different doses. Samples were obtained from a healthy donor and exposed to {sup 60}Co source (Gammacel 220 ) located in the Department of Nuclear Energy of Pernambuco Federal University (DEN/UFPe/Brazil) with a rate of air Kerma to 3,277 Gy/h. Exposures resulted in absorbed dose 0.51 Gy and 0.77 Gy. Mitotic metaphases were obtained by culturing lymphocytes for chromosome analysis and the slides were stained with 5% Giemsa. Among the unstable chromosomal aberrations the dicentric chromosomes, ring chromosomes and acentric fragments were analyzed. To calculate the significance level the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. To calculate the significance level of the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. The results showed that there was significant difference of the frequencies of dicentric chromosomes (from 0.18 to 0.51 to 0.37 Gy to 0.77 Gy), however there was no statistically significant difference between the frequencies of acentric fragments ( 0.054 to 0, 51 Gy to 0.063 to 0.77 Gy) and ring chromosomes (0.001 to 0.51 Gy to 0.003 to 0.77 Gy). The low number of rings is found justified, considering that in irradiated human lymphocytes, its appearance is rare relative to dicentrics. The results confirm that dicentrics are the most reliable biomarkers in estimating dose after exposure to gamma radiation. These two points will make the calibration curve dose-response being built for Biological Dosimetry Laboratory of CRCN-NE/CNEN.

  6. Differential gene expression in human fibroblasts after alpha-particle emitter (211)At compared with (60)Co irradiation

    DEFF Research Database (Denmark)

    Danielsson, Anna; Claesson, Kristina; Parris, Toshima Z;

    2013-01-01

    trastuzumab monoclonal antibody (0.25, 0.5, and 1 Gy) and (60)Co (1, 2, and 3 Gy). Results: We report gene expression profiles that distinguish the effect different radiation qualities and absorbed doses have on cellular functions in human fibroblasts. In addition, we identified commonly expressed transcripts...

  7. Effects of 60 Co-γ Ray Irradiation on the Seed Germination and Seedling Growth of Bauhinia variegata%60Co-γ辐照对洋紫荆种子发芽及幼苗生长的影响

    Institute of Scientific and Technical Information of China (English)

    徐佳琦; 戚嘉敏; 朱雯; 许逸林; 奚如春

    2016-01-01

    Different doses(0, 20, 40, 60, 80, 100 Gy) of 60Co-γ ray irradiation were applied to the dry Bauhinia variegata seeds and the effects on seed germination and seedling growth were investigated to explore the mutagenic effects of radiation. The results showed that with the increase of radiation the seed germination rate decreased first and rise again, decreasing from 51.66%(20 Gy) to 42.66%(60 Gy) and rising to 54.33%(100 Gy) after 6 months. Irradiation can promote the growth of the radical, the radical increased from 2.49 cm in the control group to 3.28 cm. Seed germination rate and seedling survival rate were reduced in the irradiation treatment of 40~60 Gy. The inhibition effect on seedling height and its ground diameter growth were found by radiation after seedling grew for six months. Also, the inhibition effect were found on the angle of leaf. However, no obvious deformity in the seedling morphology was found.%分别采用0,20,40,60,80,100 Gy 剂量的60Co-γ射线辐射洋紫荆(Bauhinia variegata)种子,观察测定其种子发芽率和幼苗生长指标,研究辐照对洋紫荆种子的诱变效应。结果表明,在0~100 Gy 辐射剂量内,随着辐照剂量的增加,洋紫荆种子发芽率出现先下降再上升的趋势,由51.66%(20 Gy)降至42.66%(60 Gy),又升高至54.33%(100 Gy)。一定剂量的辐照能促进胚根的生长,其中20 Gy 的辐射下平均胚根长度为3.28 cm,显著大于对照组(2.49 cm)(P<0.05)。40~60 Gy 辐射剂量使种子发芽率和幼苗成活率降低。各辐照处理对幼苗苗高、地径生长具有明显抑制作用,幼苗生长6个月后,各辐照组苗高、地径均显著小于对照组(P<0.05),同时对叶片分裂角度也具有一定的抑制作用但幼苗未出现致畸形态。

  8. Proteomics study of progeny of normal human liver cells irradiated by 60Coγ-rays%60Coγ射线照射后人肝细胞子代克隆的蛋白质组学研究

    Institute of Scientific and Technical Information of China (English)

    左雅慧; 王放; 王小莉; 李建国; 王仲文; 童建

    2009-01-01

    目的 探讨经不同剂量60C0 γ射线照射人正常肝细胞后子代克隆的蛋白质表达图谱变化,并对受照射后肝细胞子代的差异蛋白进行质谱鉴定.方法 人正常肝细胞7702分别经不同剂量60Coγ射线照射后,存活细胞克隆继续传代培养至40代,提取细胞总蛋白,进行双向电泳测定,凝胶银染和考染显色,用[mageMaster 2D Platium 510软件对获得的蛋白图谱加以分析,寻找差异表达的蛋白质.选取差异点,胶内原位酶解后进行MALDI-TOF分析和数据库搜索.结果 与对照组相比,各剂量点双向电泳图谱共发现2倍以上差异蛋白质点42个,上调10个,下调32个.成功鉴定出了17个共同差异表达蛋白,这些差异蛋白包括翻译控制肿瘤蛋白、热休克蛋白、氯离子通道蛋白、真核翻译起始因子等.结论 不同剂量的照射可导致人肝细胞子代克隆蛋白质图谱的改变,筛选出的差异蛋白可为探讨电离辐射诱发的基因组不稳定性及其分子机制提供实验依据和理论基础.%Objective To characterize the differential protein expression in the progeny of human liver ceils surviving from ionizing radiation by the proteomic analysis.Methods Two-dimensional electrophoresis gel coupled with mass spectrometry was used to explore the specific protein expression in the progeny of 7702 human liver cells surviving from ionizing radiation.Alterations in expression level of protein spots between the control and the progeny groups were statistically analyzed by ImageMaster 2D Platinum software and mass spectrometry was used to identify the protein spots with significantly altered expression-level.Results The progeny of irradiated ceils were derived from human liver cell line exposed to 0,2,4,6 Gy of 60Co γ-irradiatian.A total of 42 differentially expressed proteins between the control and the progeny of the irradiated cells groups were screened,of which 17 were identified by matrix assistant laser desorption

  9. 255Gy irradiated tachyzoites of Toxoplasma gondii induce intestinal immune response in C57BL/6J immunized by oral route

    Energy Technology Data Exchange (ETDEWEB)

    Galisteo Junior, Andres Jimenez; Alves, Janaina Baptista [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Biologia Molecular]. E-mail: galisteo@usp.br; Hiramoto, Roberto Mitsuyoshi [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Secao de Parasitoses Sistemicas]. E-mail: hiramoto@usp.br; Carmo, Claudia Villano do; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil). Lab. de Protozoologia]. E-mail: hfandrad@usp.br

    2005-07-01

    Toxoplasmosis, a prevalent widespread infection in man and animals, occurs mainly through ingestion of water and food contaminated with oocyst from cat feces, causing usually benign disease in humans, except in intrauterine fetal infection or in immunodeficient patients. We study the oral route for the development of a vaccine for toxoplasmosis, using parasites irradiated with 60 Cobalt, as an alternative for vaccine development to this worldwide parasitic infection. We evaluated the development of immunity at serum or mucosal levels, and their efficiency in protect the mice against challenge with oral cysts of the ME-49 strain. C57Bl/6j isogenic mice were immunized by oral route with 10{sup 7} 255 Gy irradiated tachyzoites from RH strain, at several protocols using milk as anti-peptic adjuvant and alum hydroxide as antacid. The preparations of irradiated tachyzoites induced production of serum IgG and IgA in immunized mice, as determined by ELISA, with IgG2a as the dominant subclass, similar to chronic infection. Their use with adjuvant allowed the excretion of significant amounts of IgA in stools also IgG, despite a lesser extent. All oral preparations induced some quantitative protection against challenge, which was similar to the parenteral route only isolated alum hydroxide was used as adjuvant. All these data support the possibility of the development of an oral vaccine against toxoplasmosis, using irradiated tachyzoites, which would be possible tool in near future for use in field baits, for immunizing either domestic or wild felids. (author)

  10. Comparison of base substitutions in response to nitrogen ion implantation and 60Co-gamma ray irradiation in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Xie Chuan-Xiao

    2004-01-01

    Full Text Available To identify the specificity of base substitutions, a novel experimental system was established based on rifampicin-resistant (Rif r mutant screening and sequencing of the defined region of the rpoB gene in E. coli. We focused on comparing mutational spectra of base substitutions induced by either low energy nitrogen ion beam implantation or 60Co-gamma rays. The most significant difference in the frequency of specific kinds of mutations induced by low energy nitrogen ion beam was that CG ®TA transitions were significantly increased from 32 to 46, AT ®TA transversions were doubled from 7 to 15 in 50 mutants, respectively. The preferential base substitutions induced by nitrogen ion beam implantation were CG ®TA transitions, AT ®GC transitions, AT ®TA transversions, which account for 92.13% (82/89 of the total. The mutations induced by 60Co-gamma rays were preferentially GC ®AT and AT ®GC transitions, which totaled 84.31% (43/51.

  11. Replication of simian virus 40 in simian virus 40-transformed hamster kidney cells induced by mitomycin C or /sup 60/Co. gamma. irradiation

    Energy Technology Data Exchange (ETDEWEB)

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

    1978-07-15

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

  12. Production of ochratoxin a by aspergillus ochraceus NRRL-3174 before and after exposures to /sup 60/Co irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Applegate, K.L.; Chipley, J.R.

    1976-03-01

    Spores from the toxigenic organism Aspergillus ochraceus NRRL-3174 were exposed to specific levels of gamma irradiation and then allowed to germinate on selected media. Increases in ochratoxin A production by irradiated, compared to non-irradiated, spores were observed after inoculation of spores onto a cracked red wheat or into a synthetic liquid medium. Variations in daily ochratoxin production were also observed for control and irradiated spore-derived cultures developing on both media, with maximum toxin production varying from 7 to 11 days of incubation. The most notable increases in ochratoxin A production occurred from cultures developing from spores having been irradiated with 10, 25, or 50 krad. Exposures to 400 or 600 krad resulted in complete inhibition of spore germination and, consequently, no ochratoxin production. Of the two substrates used, wheat and synthetic, the quantities of ochratoxin A produced were significantly lower in the synthetic media than on the natural substrate. Higher and more rapid toxin production occurred from spores having been irradiated with 10, 25, 50, and 100 krad than occurred from the non-irradiated control spores when grown on synthetic media. Cultures derived from spores having been exposed to 10, 25, and 50 krad produced significantly higher levels of ochratoxin A after 8 days of incubation on natural substrate than did the controls. Analysis of variance revealed that substrate, length of incubation, as well as irradiation levels all affected the time required to produce maximum levels of ochratoxin A.

  13. Differential Expression of Retrotransposon WIS 2-1A Response to Vacuum,Low-Energy N+ Implantation and 60Coγ-ray Irradiation in Wheat

    Institute of Scientific and Technical Information of China (English)

    ZHAO Huiru; GU Yunhong; YA Huiyuan; JIAO Zhen; QIN Guangyong

    2009-01-01

    Mutagenesis and retrotransposons have a close relationship,but little attention has been paid yet to the activity of rtrotransposons produced by physical mutagens. The variation of retrotransposon WIS 2-1A activity in wheat(Triticum aestivum L.)embryos at three different growth times(30 h,45 h and 60 h)was investigated after they had been treated with N+ implantation in a vacuum of 5x10-2 Pa and irradiation by 60Coγ-ray respectively.For each of the three growth times the expression of WIS 2-1A showed almost entirely a same trend of downregulation,upregulation,then downregulation,and upregulation again with the increase in dose of N+ implantation,but the expression appeared irregular with the increase in irradiation of 60Coγ-ray.In conclusion,the acutely activating effect of WIS 2-1A stimulated by vacuum and high dose N+ implantation within a shorter incubation time may provide a convenient tool to advance the research on mutagenic breeding and function genes.

  14. Impaired colony-forming ability following. gamma. irradiation of skin fibroblasts from tuberous scierosis patients. [/sup 60/Co

    Energy Technology Data Exchange (ETDEWEB)

    Paterson, M.C.; Sell, B.M.; Smith, B.P.; Bech-Hansen, N.T.

    1982-05-01

    The radiosensitivity of cultured dermal fibroblasts from human subjects afflicted with tuberous sclerosis (TS), a hereditary neurocutaneous syndrome, was assessed by assaying loss of colony-forming ability in response to acute ..gamma..-ray exposure. Related to control strains from clinically normal donors, three cell lines (GM1635, GM1643, GM2333) from two affected patients displayed enhanced sensitivity to inactivation by /sup 60/Co ..gamma..-ray treatment, whether administered oxically (air-saturated) or hypoxically (N/sub 2/-gassed); a fourth strain (GM1644) from a third patient exhibited normal radiosensitivity under both treatment conditions. The post-..gamma..-irradiaton colony-forming ability of the three hypersensitive TS strains was intermediate between that of normal controls and that of strains from patients inheriting the radiotherapy-sensitive neurovascular disorder ataxia telangiectasia. The variability in the radioresponse of the TS stains (three sensitive and one normal) is not surprising, considering the widely recognized clinical heterogeneity in the disease. Our findings, aside from providing a laboratory marker for early (possible presymptomatic) detection of persons at high risk for TS, may lead to a better understanding of the origin and progressive development of this multifaceted syndrome.

  15. Effects of prenatal /sup 60/Co irradiation on postnatal neural, learning, and hormonal development of the squirrel monkey

    Energy Technology Data Exchange (ETDEWEB)

    Ordy, J.M.; Brizzee, K.R.; Dunlap, W.P.; Knight, C.

    1982-02-01

    The goals of this study were to examine the effects of 0, 50, and 100 rad of /sup 60/Co administered prenatally on postnatal development of neuromuscular coordination, visual discrimination learning, spontaneous light-dark stabilimeter activity, plasma cortisol, and somatometric growth rates of diurnal squirrel monkeys from birth to 90 days. In terms of accuracy, completeness, and time required for performance of reflexes and neuromuscular coordination, the performance of 50- and 100-rad offspring was less accurate and poorly coordinated and required more time for completion to that of controls. In visual orientation, discrimination, and reversal learning, the percentage correct responses of the 50- and 100-rad offspring were significantly lower than those of controls. Spontaneous light-dark stabilimeter activity of 50- and 100-rad offspring was significantly higher in the dark session than that of controls. Plasma cortisol was significantly higher in 100-rad infants than in controls. Comparisons of somatometric growth rates indicated that postnatal head circumference, crown-rump length, and to a lesser extent body weight increased at significantly slower rates in 50- and 100-rad offspring. These findings should provide essential information for formulating and carrying out multivariate behavioral, biochemical, and morphometric assessments of low-dose effects on the brain of primate offspring within demonstrable dose-response curves.

  16. Structural and optical analysis of 60Co gamma-irradiated thin films of polycrystalline Ga10Se85Sn5

    Science.gov (United States)

    Ahmad, Shabir; Asokan, K.; Shahid Khan, Mohd.; Zulfequar, M.

    2015-12-01

    The present study focuses on the effects of gamma irradiation on structural and optical properties of polycrystalline Ga10Se85Sn5 thin films with a thickness of ∼300 nm deposited by the thermal evaporation technique on cleaned glass substrates. X-ray diffraction patterns of the investigated thin films show that crystallite growth occurs in the orthorhombic phase structure. The surface study carried out by using the scanning electron microscope (SEM) confirms that the grain size increases with gamma irradiation. The optical parameters were estimated from optical transmission spectra data measured from a UV-vis-spectrophotometer in the wavelength range of 200-1100 nm. The refractive index dispersion data of the investigated thin films follow the single oscillator model. The estimated values of static refractive index n0, oscillator strength Ed, zero frequency dielectric constant ε0, optical conductivity σoptical and the dissipation factor increases after irradiation, while the single oscillator energy Eo decreases after irradiation. It was found that the value of the optical band gap of the investigated thin films decreases and the corresponding absorption coefficient increases continuously with an increase in the dose of gamma irradiation. This post irradiation changes in the values of optical band gap and absorption coefficient were interpreted in terms of the bond distribution model.

  17. Optimization of process parameters for the inactivation of Lactobacillus sporogenes in tomato paste with ultrasound and 60Co- γ irradiation using response surface methodology

    Science.gov (United States)

    Ye, Sheng-Ying; Qiu, Yuan-Xin; Song, Xian-Liang; Luo, Shu-Can

    2009-03-01

    The processing parameters for ultrasound and 60Co- γ irradiation were optimized for their ability to inactivate Lactobacillus sporogenes in tomato paste using a systematic experimental design based on response surface methodology. Ultrasonic power, ultrasonic processing time and irradiation dose were explored and a central composite rotation design was adopted as the experimental plan, and a least-squares regression model was obtained. The significant influential factors for the inactivation rate of L. sporogenes were obtained from the quadratic model and the t-test analyses for each process parameter. Confirmation of the experimental results indicated that the proposed model was reasonably accurate and could be used to describe the efficacy of the treatments for inactivating L. sporogenes within the limits of the factors studied. The optimized processing parameters were found to be an ultrasonic power of 120 W with a processing time of 25 min and an irradiation dose of 6.5 kGy. These were measured under the constraints of parameter limitation, based on the Monte Carlo searching method and the quadratic model of the response surface methodology, including the a/ b value of the Hunter color scale of tomato paste. Nevertheless, the ultrasound treatment prior to irradiation for the inactivation of L. sporogenes in tomato paste was unsuitable for reducing the irradiation dose.

  18. Optimization of process parameters for the inactivation of Lactobacillus sporogenes in tomato paste with ultrasound and {sup 60}Co-{gamma} irradiation using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Ye Shengying [College of Food Science, South China Agricultural University, Wushan, Guangzhou, GD 510640 (China)], E-mail: yesy@scau.edu.cn; Qiu Yuanxin; Song Xianliang; Luo Shucan [College of Food Science, South China Agricultural University, Wushan, Guangzhou, GD 510640 (China)

    2009-03-15

    The processing parameters for ultrasound and {sup 60}Co-{gamma} irradiation were optimized for their ability to inactivate Lactobacillus sporogenes in tomato paste using a systematic experimental design based on response surface methodology. Ultrasonic power, ultrasonic processing time and irradiation dose were explored and a central composite rotation design was adopted as the experimental plan, and a least-squares regression model was obtained. The significant influential factors for the inactivation rate of L. sporogenes were obtained from the quadratic model and the t-test analyses for each process parameter. Confirmation of the experimental results indicated that the proposed model was reasonably accurate and could be used to describe the efficacy of the treatments for inactivating L. sporogenes within the limits of the factors studied. The optimized processing parameters were found to be an ultrasonic power of 120 W with a processing time of 25 min and an irradiation dose of 6.5 kGy. These were measured under the constraints of parameter limitation, based on the Monte Carlo searching method and the quadratic model of the response surface methodology, including the a/b value of the Hunter color scale of tomato paste. Nevertheless, the ultrasound treatment prior to irradiation for the inactivation of L. sporogenes in tomato paste was unsuitable for reducing the irradiation dose.

  19. 60Coγ射线辐照不同麻种种子的细胞学效应%Cytological Effects on Seeds of Hibiscus cannabinus and Cannabis sativa Irradiated by 60Coγ ray

    Institute of Scientific and Technical Information of China (English)

    周立人; 吴雪琴; 魏晓飞; 李布青

    2003-01-01

    通过5种不同剂量的60Coγ射线对两个不同麻种3个品种材料的种子辐照效应研究表明,低剂量的60Coγ射线辐照能促进麻类作物根尖细胞的有丝分裂.但随着γ射线辐照剂量的增加,根尖细胞有丝分裂指数呈不同程度的下降趋势.60Coγ射线辐照能诱发根尖细胞的染色体畸变和核畸变,出现桥、断片、落后染色体、微核、双核、小核等多种畸变类型,并且辐照剂量越大,根尖细胞畸变类型越多,变异频率越高.研究结果还表明不同麻种、同一麻种不同品种对60Coγ射线的辐射敏感性不同,红麻中杂红305最强,红麻福红2号次之,大麻最弱.

  20. Effects of Pre-exposure of Mouse Pituitary with Low-dose 60Co γ-ray on Male Reproductive Endocrine Capacity Induced by Subsequent High-dose Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZhangHong; LiWenjian; JingXiaodong; LiuBing; MinFengling; ZhouQingming; XieYi

    2003-01-01

    To investigate the effects of pre-exposure of mouse pituitary with low-dose 60Co γ-ray on male reproductive endocrine capacity induced by subsequent high-dose irradiation, the pituitary of the B6C3F1 hybrid strain male mice were irradiated with 0.05 Gy of 60Co γ-ray as the pre-exposure dose (D1), and were then irradiated with 2 Gy of 60Co γ-ray as challenging irradiation dose (D2) at 4 h after per-exposure. Pituitary gonadotroping hormones --follicle-stimulating hormone (FSH) and luterinzing hormone (LH), serum testosterone, testis weight and sperm count were measured at 35th day after irradiation.

  1. Effect of {sup 60}Co gamma-irradiation on two-dimensional electron gas transport and device characteristics of AlGaN/GaN HEMTs

    Energy Technology Data Exchange (ETDEWEB)

    Umana-Membreno, G.A.; Dell, J.M.; Parish, G.; Nener, B.D.; Faraone, L. [School of Electrical, Electronic and Computer Engineering, The University ofWestern Australia, Crawley WA 6009 (Australia); Ventury, R.; Mishra, U.K. [Dept. of Electrical and Computer Engineering, University of California, Santa Barbara, CA 93106 (United States)

    2005-05-01

    The effect of {sup 60}Co gamma-irradiation on Al{sub 0.33}Ga{sub 0.67}N/GaN high-electron-mobility transistors (HEMTs) has been investigated using DC and geometrical magnetoresistance measurements. The devices studied were of similar epitaxial structure, yet differed in the doping levels of the Al{sub 0.33}Ga{sub 0.67}N barrier layer: (A) nominally undoped and (B) Si-doped with SiN{sub x} passivation. Exposure to cumulative gamma-ray doses up to 20 Mrad(Si) is shown to induce significant changes in drain-current level, threshold voltage and gate leakage current level. Analysis of magnetoresistance characteristics measured at 80 K indicated that irradiation induced an increase in two-dimensional electron-gas (2DEG) density, which leads to negative threshold voltage shifts observable in the drain current versus gate voltage characteristics, attributable to the introduction of defect centers in the Al{sub 0.33}Ga{sub 0.67}N layer and/or at the gate-AlGaN interface. The 2DEG mobility-concentration profiles are shown to remain approximately unchanged for doses up to 20 Mrad(Si). Device failure, evidenced as loss of gate control over the channel and/or excessive gate leakage, occurred after exposure to 30 Mrad(Si) for device A, whereas sample B failed after 20 Mrad(Si) total dose due to failure of half of the gate contact. Degradation of gate and source/drain contacts characteristics with total dose appears to limit the tolerance of the studied HEMTs to {sup 60}Co gamma-irradiation. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Toxoplasma gondii gamma irradiation using Co-60; Irradiacao do Toxoplasma gondii com gama do {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Serra-Freire, Nicolau Maues [Universidade Federal Rural do Rio de Janeiro, RJ (Brazil). Dept. de Parasitologia Animal; Maliska, Carmelindo [Hospital Central do Exercito, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear; Norberg, Antonio Neres [Instituto de Biologia do Exercito (IBEx), Rio de Janeiro, RJ (Brazil)

    1996-07-01

    The use of nuclear power through radiation for the destruction of microorganisms which cause food deterioration, infections and toxicosis, is specifically for peaceful purposes. Toxoplasma gondii is a protozoa responsible for illnesses in humans and animals. One of the most common ways of transmission is through raw or poorly cooked meat. There is little information on the resistance of T. gondii to radiation. The objective of this research is to determine the Minimum Lethal Dose (MLD) of gamma radiation for those microorganisms. Suspensions of T. gondii containing approximately one million taquizoites/ml were irradiated with doses between up 0,01 up to 0,15 kGy (Kilogray) and inoculated to mice. The surviving T. gondii were re-irradiated with 0,01 up to 0,16 kGy. The irradiated protozoa were totally destroyed with a 0,15 kGy dose (MLD). Taquizoites issued from live protozoa of 0,14 kGy also were completely destroyed with dose of 0,15 kGy. No increase in resistance was observed regarding the non irradiated protozoa. (author)

  3. Pregnancy-dependent initiation in tumorigenesis of Wistar rat mammary glands by sup 60 Co-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Inano, Hiroshi; Suzuki, Keiko; Ishii-Ohba, Hiroko; Ikeda, Kiyomi (National Inst. of Radiological Sciences, Chiba (Japan)); Wakabayashi, Katsumi (Gunma Univ., Maebashi (Japan). Hormone Assay Center)

    1991-06-01

    Pregnant Wistar rats received whole body irradiation with 260 cGy {gamma}-rays at days 7, 14 and 20 of pregnancy and then were treated with diethylstilbestrol (DES) for 1 year. The highest incidence (92.9%) for tumorigenesis of mammary glands was observed in the rats irradiated in late pregnancy. Histological examination showed that tumors were classified as fibroadenoma and adenocarcinoma. To determine the reasons for specific induction of mammary tumors by irradiation in late pregnancy, hormone concentrations in serum and estrogen receptors in mammary glands during pregnancy were measured. Concentrations of estradiol, progesterone, 11-deoxycorticosterone and placental lactogen at day 20 were higher than at days 7 and/or 14, but no difference was observed in the concentrations of prolactin and thyroid-stimulating hormone during pregnancy. The estrogen receptor in mammary glands at day 20 was indicated to have the highest affinity and the highest binding capacity during pregnancy. Normal mammary glands at day 20 were suggested to have more abundant epithelial cells in the mammary lobes than those at days 7 and 14. The data suggest that the critical requirements for the initiation of tumorigenesis by {gamma}-rays are dependent upon the differentiated state of mammary glands exposed to various hormones, and that the concentration and persistence of the synthetic estrogen (DES) are necessary for the promotion of tumorigenesis of the irradiated mammary glands. (Author).

  4. 60Co γ-rays irradiation effect in DC performance of AlGaN/GaN high electron mobility transistors

    Institute of Scientific and Technical Information of China (English)

    Gu Wenping; Chen Chi; Duan Huantao; Hao Yue; Zhang Jincheng; Wang Chong; Feng Qian; Ma Xiaohua

    2009-01-01

    Unpassivated/passivated AlGaN/GaN high electron mobility transistors(HEMTs) were exposed to 1.25MeV60Co γ-rays at a dose of 1 Mrad(Si).The saturation drain current of the unpassivated devices decreased by 15%at 1 Mrad γ-dose,and the maximal transconductance decreased by 9.1% under the same condition;moreover,either forward or reverse gate bias current was significantly increased,while the threshold voltage is relatively unaffected.By sharp contrast,the passivated devices showed scarcely any change in saturation drain current and maximal transconductance at the same γ dose.Based on the differences between the passivated HEMTs and unpassivated HEMTs,adding the C-V measurement results,the obviously parameter degradation of the unpassivated AlGaN/GaN HEMTs is believed to be caused by the creation of electronegative surface state charges in source-gate spacer and gate-drain spacer at the low dose (1 Mrad).These results reveal that the passivation is effective in reducing the effects of surface state charges induced by the 60Co γ-rays irradiation.so the passivation is an effective reinforced approach.

  5. Mortality and growth of cobalt-60 gamma-irradiated adult Pacific oyster, Crassotrea gigas%60Co-γ射线对成体长牡蛎生长的影响及致死效应

    Institute of Scientific and Technical Information of China (English)

    刘晓; 彭小明; 张国范; 赵敏; 郭希明

    2005-01-01

    Effects of ionizing irradiation of 60Co-γ ray on mortality and growth of one year-old Pacific oysters ( Crassotrea gigas ) were studied. Irradiation was conducted at 4℃ and without sea water, and the survival, shell length, shell width, whole wet weight and condition index of irradiated oysters were measured. A biphasic dose response effect of 660Co-γ irradiation on Pacific oyster with high stimulatory response dose range to 100 Gy, and strong hormesis effects had been observed. Gamma ray induced mortality happened within 90 days after irradiation, and the relation between dosage ( D ) and mortality at 90 days could be described by the equation of M90 = 0.0041D2- 0. 1816D (R2= 0. 9958) with an LD50/90 of 135 Gy, indicating that the Pacific oyster has strong resistance to 60Coirradiation. Growth in shell length, shell width and whole wet weight of Pacific oyster were also enhanced by 60 Gy of 60Co-γ ray. The condition index was also enhanced by 60Coirradiation in the dosage range from 40 to 100 Gy, with the maximum stimulatory response of 2.5 fold of control value at the 40 Gy dosage, suggesting that the accelerating effects of γ ray on growth of the Pacific oyster led to increase in dry meat. Results of this study showed that ionizing irradiation might be useful in the improvement of production traits in shellfish.

  6. {sup 60}Co gamma-irradiation effects on electrical properties of a rectifying diode based on a novel macrocyclic Zn octaamide complex

    Energy Technology Data Exchange (ETDEWEB)

    Ocak, Y.S. [Department of Science, Faculty of Education, University of Dicle, Diyarbakir (Turkey); Kilicoglu, T., E-mail: kilicoglutahsin@gmail.co [Department of Physics, Faculty of Art and Science, University of Batman, Batman (Turkey); Department of Physics, Faculty of Art and Science, University of Dicle, Diyarbakir (Turkey); Topal, G. [Department of Chemistry, Faculty of Education, University of Dicle, Diyarbakir (Turkey); Baskan, M.H. [Department of Physics, Faculty of Education, University of Dicle, Diyarbakir (Turkey)

    2010-01-01

    C{sub 36}H{sub 28}N{sub 12}O{sub 8}ZnCl{sub 2}.9/2H{sub 2}O, Zn-octaamide (ZnOA) macrocyclic compound was synthesized to be used in the fabrication of electronic and photoelectronic devices. The structure of new compound was identified by using {sup 1}H NMR, {sup 13}C NMR, IR, UV-vis and LC-MS spectroscopic methods. The Sn/ZnOA/n-Si/Au structure was engineered by forming a thin macrocyclic organic compound layer on n-Si inorganic substrate and then by evaporating Sn metal on the organic layer. It was seen that the device had a good rectifying behaviour and showed Schottky diode properties. The diode was irradiated under {sup 60}Co gamma-source at room temperature. Characteristic parameters of the diode were determined from its current-voltage (I-V) and capacitance voltage (C-V) measurements before and after irradiation. It was observed that gamma-irradiation had clear effects on I-V and C-V properties. Also, it was seen that the barrier height, the ideality factor and the series resistance values decreased after the applied radiation, while the saturation current value increased.

  7. Effects of Pre-exposure Mouse Pituitary with Low-dose 60Co γ-ray on Growth Hormone (GH) and Body Mass Induced by Subsequent High-dose Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZhangHong; LiWenjian; JingXiaodong; LiuBing; MinFengling; ZhouQingming; XieYi

    2003-01-01

    The pituitary of the B6C3F1 hybrid strain mice were irradiated with 0.05 Gy of 60Co γ-ray as the pre-exposure dose (D1), and were then irradiated with 2 Gy of 60Co γ-ray as challenging irradiation dose (D2) at 4h after per-exposure. Body weight and serum growth hormone (GH) were measured at 35th day after irradiation. The results showed that irradiation of mouse testes with 2 Gy of 60Co γ-ray significantly diminished mousebody weight and level of serum GH (Table). Pre-exposure with a low-dose (0.05 Gy) of 60Co γ-ray significantly alleviated reductions of mouse body weight and level of serum GH induced by subsequent a high-dose (2 Gy) irradiation (Table). The data suggested that low-dose ionizing irradiation can induce adaptive responses to the harmful effects of pituitary by subsequent high-dose exposure.

  8. A Green Platform for Preparation of the Well-Defined Polyacrylonitrile: 60Co γ-ray Irradiation-Initiated RAFT Polymerization at Room Temperature

    Directory of Open Access Journals (Sweden)

    Shuangshuang Zhang

    2017-01-01

    Full Text Available 60Co γ-ray irradiation-initiated reversible addition–fragmentation chain transfer (RAFT polymerization at room temperature with 2-cyanoprop-2-yl 1-dithionaphthalate (CPDN as the chain transfer agent was first applied to acrylonitrile (AN polymerization, providing a “green” platform for preparing polyacrylonitrile (PAN-based carbon fibers using an environment-friendly energy source. Various effects of dose rate, molar ratio of the monomer to the chain transfer agent, monomer concentration and reaction time on the AN polymerization behaviors were performed to improve the controllability of molecular the weight and molecular weight distribution of the obtained PAN. The feature of the controlled polymerization was proven by the first-order kinetics, linear increase of the molecular weight with the monomer conversion and a successful chain-extension experiment. The molecular weight and molecular weight distribution of PAN were characterized by size exclusion chromatography (SEC. 1H NMR and Matrix assisted laser desorption ionization/time of flight mass spectra (MALDI-TOF-MS confirmed the chain-end functionality of PAN, which also was supported by the successful chain-extension experiments of original PANs with acrylonitrile and styrene as the second monomers respectively.

  9. Living/controlled free radical copolymerization of chlorotrifluoroethene and butyl vinyl ether under 60Co γ-ray irradiation in the presence of S-benzyl O-ethyl dithiocarbonate.

    Science.gov (United States)

    Liu, Lei; Lu, Dan; Wang, Hu; Dong, Qibao; Wang, Pucheng; Bai, Ruke

    2011-07-21

    Living/controlled free radical copolymerization of chlorotrifluoroethene and butyl vinyl ether has been successfully achieved at room temperature under (60)Co γ-ray irradiation in the presence of S-benzyl O-ethyl dithiocarbonate. The alternating and block copolymers have been obtained with well-defined molecular weights and narrow molecular weight distributions.

  10. 大剂量rhG-CSF早期单次给药对60Coγ射线照射小鼠的治疗作用%Therapeutic effects of early administration of a single high dose of rhG-CSF on mice irradiated by 60Coγ rays

    Institute of Scientific and Technical Information of China (English)

    韩阿如娜; 余祖胤; 柳晓兰; 从玉文

    2011-01-01

    Objective To observe the therapeutic effects of early administration with a single high dose of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on mice irradiated with 60Co γ rays, and provide a reference for the treatment of acute radiation syndrome (ARS) by using cytokines. Methods Male C57 mice underwent a total body irradiation of 8. Ogy 60Co y ray, and they were treated with rhG-CSF, at 0.5h and 24h, subcutaneously in a dose of 2, 1 and 0. 5mg/kg, respectively. The 30-day survival rate and mean survival time were observed in the lethal irradiated mice. The peripheral blood cell counts and bone marrow nucleated cell counts were evaluated in the sublethally irradiated mice. Results Early administration of a high dose of rhG-CSF significantly increased 30-day survival rate and prolonged mean survival time of mice with lethal irradiation dose. A single injection of rhG-CSF (lmg/kg) at 0. 5h after irradiation was an optimal administration schedule. In addition, early administration with a single high dose of rhG-CSF improved the recovery of bone marrow nucleated cell counts and peripheral blood counts, including white blood cell (WBC), red blood cell (RBC) and platelet in mice exposed to 6. Ogy irradiation. Conclusion Early administration of a single high dose rhG-CSF may have a favorable therapeutic effect on mice irradiated with 60Co y ray.%目的 观察大剂量rhG-CSF早期单次给药对60Coγ射线照射小鼠的治疗作用,为细胞因子治疗急性放射病提供实验依据.方法 雄性C57小鼠,经8.0Gy 60Co γ射线全身照射后于0.5、24h各皮下注射一次不同剂量rhG-CSF(2、1mg/kg和0.5mg/kg),观察致死剂量照射小鼠的30d存活率及平均生存时间.小鼠经6.0Gy 60Co γ射线全身照射后,通过不同给药方案及不同剂量rhG-CSF早期干预,观察亚致死剂量照射小鼠的外周血象和骨髓有核细胞数的变化.结果 大剂量rhG-CSF早期干预明显提高致死剂量照射小鼠的30d存

  11. Characterization of {sup 60}Co and {sup 137}Cs beams from irradiator Shepherd 81 - 14D of LNMRI/IRD in radiation protection; Caracterizacao dos feixes de {sup 60}Co and {sup 137}Cs do Irradiador Shepherd 81 - 14D do LNMRI/IRD em radioprotecao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, C.N.M. da; Cabral, T.S., E-mail: cosme@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The objective of this work is the characterization of {sup 60}Co beams and the {sup 137}Cs irradiator Shepherd 81-14D acquired by the National Metrology Laboratory of Ionising Radiation of the Institute of Radiation Protection and Dosimetry (LNMRI /IRD), for use in calibration of measuring instruments of gamma radiation in air kerma and ambient dose equivalent, irradiation of films and TLD's. Field homogeneity measurements were carried out, calculated input and output time of the source and commissioning of sources. (author)

  12. Cytotoxicity evaluation of Diethyltoluamide (DEET) in Perna perna (Linnaeus, 1758) mussels non-irradiated and irradiated with {sup 60}Co gamma radiation; Avaliacao da citotoxicidade do dietiltoluamida (DEET) em mexilhoes Perna perna (Linnaeus, 1758) irradiados e nao irradiados com radiacao gama de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Martini, Gisela de Assis

    2013-07-01

    Recent studies have identified the presence of several emerging pollutants in aquatic environments. The occurrence in different environmental matrices has been continuously reported, highlighting the need for toxicity studies. The DEET (N,N-diethyl-meta-toluamide) is the active ingredient used in most insect repellents, and is present in many commercially available formulations. Apart from chemical pollutants, aquatic organisms are subject to exposure of ionizing radiation from natural sources or in the vicinity of nuclear power plants. The present study evaluated the toxicity of DEET in organisms irradiated and non-irradiated with {sup 60}Co gamma radiation, and the effects that radiation causes in lysosomes of hemocytes of Perna perna mussel. For this purpose, assays were performed to identify the acute toxicity of DEET concentration and the dose of gamma radiation able to cause mortality. Subsequently, cytotoxicity assays were carried out to assess the stability of the lysosomal membrane in organisms exposed to ionizing radiation and DEET. According to the results obtained in acute toxicity tests, the concentration of DEET that causes mortality of 50% exposed organisms (LC50) is 114,27 mg L{sup -1}, and the radiation dose that causes mortality (LD50) is 1068 Gy. In the cytotoxicity assays, the concentration of the non-observed effect (NOEC) for irradiated and non-irradiated organisms 0.0001 mg L-1 and observed effect concentration (LOEC) at concentrations above this. The IC25 (72h) for non-irradiated organisms was 0.0003 mg L-1 and IC50 (72h) was 0.0008 mg L{sup -1} for irradiated and non-irradiated organisms. Despite of the concentrations of effect found in this study were higher than in the environment, both measurements are in the same order of magnitude and should be also take into account the possible synergistic effects of DEET with other contaminants in the aquatic environment. (author)

  13. Effect of sodium alginate coating and 60Coirradiation treatment on fresh-keeping of golden silk jujube%海藻酸钠涂膜及60Co-γ辐照处理对小枣的保鲜作用

    Institute of Scientific and Technical Information of China (English)

    杨伟; 徐莹; 樊燕; 汪东风; 孙寿魁

    2012-01-01

    Using golden silk jujube at full-red storage as materials,the effects of different preservation treatments(60Coirradiation,coating with sodium alginate,and 60Co-γ irradiation+coating with sodium alginate,respectively) on the post-harvest fruit quality during cold storage were investigated,and the weight loss rate,total sugar content,reducing sugar content,VC content,and ratio of sugar to acid were determined.The results indicated that 60Coirradiation,coating with sodium alginate and 60Co-γ irradiation+coating with sodium alginate all had an obvious fresh-keeping effect.The result showed that the three treatments reduced water loss,delayed the decrease of VC and titratable acid content,and the increase of sugar to acid ratio,and 60Co-γ irradiation+coating with sodium alginate maintained a relatively high content of total sugar and reducing sugar.Especially,the preservative effect of the 60Co-γ irradiation+coating with sodium alginate treatment was obviously superior to the control group,60Coirradiation or coating with sodium alginate alone,which could obviously improve the quality of post-harvest cold storage of golden silk jujube.%以全红期的山东省乐陵小枣为实验材料,分别进行60Co-γ辐照处理、海藻酸钠涂膜处理及二者结合处理后,与对照组同时于(2±0.5)℃冷库贮藏,并对低温贮藏过程中枣的失重率、总糖、还原糖、VC、可滴定酸含量及糖酸比的变化进行测定。结果表明:涂膜、辐照、涂膜+辐照处理均能有效减少水分散失,延缓VC和可滴定酸的下降,抑制糖酸比的上升,涂膜+辐照处理能保持较高的总糖、还原糖含量。其中,60Co-γ辐照+海藻酸钠涂膜处理于(2±0.5)℃冷库贮藏保鲜效果显著优于其他实验处理组,有助于提高乐陵小枣采后的低温贮藏品质。

  14. Toxoplasma gondii vs ionizing radiation: intestinal immunity induced in C57bl/6j mice by irradiated tachyzoites; Toxoplasma gondii vs radiacao ionizante: estudo da imunidade intestinal em camundongos C57Bl/6j experimentalmente vacinados com taquizoitos irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Galisteo Junior, Andres Jimenez. E-mail: galisteo@usp.br

    2004-07-01

    We study the oral route for the development of a vaccine for toxoplasmosis, using parasites irradiated with 60 Cobalt, as an alternative for vaccine development to this worldwide parasitic infection. We evaluated the development of immunity at serum or mucosal levels, and their efficiency in protect the mice against challenge with oral cysts of the Me-49 strain. C57Bl/6j isogenic mice were immunized by oral route with 107 255 Gy irradiated tachyzoites from RH strain, at several protocols using milk as anti-peptic adjuvant and alum hydroxide as antacid. The preparations of irradiated tachyzoites induced production of serum IgG and IgA in immunized mice, as determined by ELISA, with IgG2a as the dominant subclass, similar to chronic infection. Their use with adjuvant allowed the excretion of significant amounts of IgA in stools also IgG, despite a lesser extent. There are suggestion of tolerance induction at mucosal level, with lower antigen induced proliferation and lower in vitro antibody production by spleen and gut lymphocytes, with the latter doses, specially when milk was used as adjuvant. All oral preparations induced some quantitative protection against challenge, which was similar to the parenteral route only isolated alum hydroxide was used as adjuvant. All these data support the possibility of the development of an oral vaccine against toxoplasmosis, using irradiated tachyzoites, which would be possible tool in near future for use in field baits, for immunizing either domestic or wild felines. (author)

  15. Effects of low dose rate 60Co γ ray combined with 252Cf neutron irradiation on hematopoietic and antioxidation systems in rats%低剂量率60Co γ射线和252Cf裂变中子混合照射对大鼠造血及抗氧化系统的影响

    Institute of Scientific and Technical Information of China (English)

    莫琳芳; 何颖; 侯登勇; 钱甜甜; 蒋定文; 王岩; 刘玉明; 李珂娴; 王庆蓉

    2013-01-01

    Objective To study the effects of low dose rate 60Co γ ray combined with 252Cf neutron irradiation on hematopoietic and antioxidation systems in rats.Methods Sixteen SD male rats were randomly divided into the irradiation group and the control group,each consisting of 8 rats.The irradiation group was exposed to whole-body 60 Co γray (with daily dose rate of 0.072 Gy) for 1 hour and to 252 Cf neutron (with daily dose rate of 0.085 mGy/h) for 20 hours,for a total of 7 successive days.Peripheral blood cell counts,main organ indices,bone marrow DNA contents,SOD activity and MDA content of rats were monitored,at day 8 after irradiation.Results Compared with those of the control group [(6.2 ± 2.4) × 109/L],WBC of the irradiation group decreased significantly following irradiation [(3.4 ± 1.2) × 109/L],(P < O.05),but no statistical significance could be noted in the changes of various organ indices (P > O.05).Bone marrow DNA contents and serum SOD activity all decreased significantly (P < 0.05),while organ indices and MDA contents seemed to increase,but without statistical significance (P > 0.05).Conclusions 60 Co γirradiation combined with 252Cf neutron irradiation could obviously damage the hemopoietic and anti-oxidation systems of rats.%目的 探讨低剂量率60Co γ射线与252Cf裂变中子混合照射对大鼠的生物效应.方法 16只雄性SD大鼠按数字表法随机分成实验组和对照组,每组8只.实验组每天依次暴露于60Co γ射线1h(剂量率为0.072 Gy/h),252Cf裂变中子20 h(剂量率为0.085 mGy/h),连续7d.照后第8天检测大鼠外周血细胞计数、主要脏器指数、骨髓DNA含量、血清超氧化物歧化酶(SOD)活力及丙二醛(MDA)含量.结果 与对照组[(6.2 ±2.4)×109/L]相比,实验组大鼠外周血白细胞数[(3.4±1.2)×109/L](WBC)显著降低(P<0.05),各项脏器指数变化组间差异无统计学意义(P>0.05),骨髓DNA含量显著降低(P<0.05);血清SOD活力显著降低(P<0

  16. The Study of Setting 60CoIrradiation does of Cumin Powder%孜然粉~(60)Co-γ射线辐照杀菌剂量的设定

    Institute of Scientific and Technical Information of China (English)

    李姣; 赵谋明; 吴军

    2009-01-01

    The pollution of cumin powder was investigated,and the impacts of irradiation dose and microbial sensitivity factors were analyzed. Results indicated Gamma irradiation was of the effective sterilization methods on polluted cumin power,particularly on the number of total bacteria and coliforms. The D_(10) value fluctuates at different time points during production,which makes it difficult to set fixed dosage; on the other hand its water activity was not significantly affected under the conditions. Therefore,with the presumption of consistent production condition,the use of control charts to monitor the initial bacteria pollution of spices could rapidly and accurately determine irradiation dose of Cumin powder.%调查了孜然粉污染情况,分析了微生物的辐照敏感性及其影响因素.结果表明,γ射线辐照对细菌总数和大肠菌群数污染严重的孜然粉有明显的杀菌效果.但由于D_(10)值随生产时间波动较大,对剂量设定造成困难,而在所确定的实验条件下,水分活度对其影响差异不显著.为此,笔者在生产状况稳定的前提下,利用控制图监测香辛料初始菌污染情况,从而可以快速确定辐照杀菌剂量.

  17. Resveratrol Effects on Life Span and Fertility of Caenorhabditis Elegans Subject to 60Co Gamma Ray Irradiation%白藜芦醇对60Coγ射线照射线虫寿命和生殖的影响

    Institute of Scientific and Technical Information of China (English)

    叶侃; 季晨博; 郭锡熔; 古桂雄

    2011-01-01

    Caenorhabditis elegans was used as experimental model to investigate radiation effect of resveratol on caenorhabdities elegans irradiated by 60Co γray. Treatment with resveratrol can increase average life span and spawning rate, improve the surrival rate of eggs, and protect their mitochondrion function of cacnorhabdities elegans exposure to 60Co rr ray. The results indicate that resveratrol has radiation protection effects, which might be related to its action on ROS decrease and mitochondrial defend.%以线虫作为实验模型,观察白藜芦醇(RES)对受60Coγ射线照射线虫的保护作用.结果表明,白藜芦醇能提高受照射线虫的寿命,增加产卵率,提高卵的存活率,保护其线粒体功能.其作用机制可能与白藜芦醇减轻氧自由基所致的线虫线粒体损伤有关.

  18. 60Co γ照射加深低温保存对大鼠同种带瓣主肺动脉免疫原性的作用%Immunogenicity in rat valved pulmonary homograft conduits with 60Co γ, irradiation and cryopreservation

    Institute of Scientific and Technical Information of China (English)

    刘英宇

    2008-01-01

    Objective The method of keeping valved pulmonary homograft conduits(VPHC) by using 60Co γ irradiation and cryopreservation is used in this experiment and the transplantation model of VPHC is built. Different effects to the immunogenicity in VPHC rat caused by different dosage of 60 Co iracliation are observed. To determine the suitable dosage of 60 Co γ used prior to cryopreservation in order to reduce the immunogenicity yet maintain the viability of VPHC. And to provide academic basis for further basic research and clinical application. Methods Fifty one-month old Wistar rats were used as donors and were divided into five groups (randomly,leave out sex ). Fifty SD adult rats were used as recipients and were divided into five groups respectively. Four experimental groups were irradiated with 60 Co γ of different dosages prior to cryopreservation:300 Gy group, 600 Gy group, 900 Gy group, 1200 Gy group. The experimental control group received cryopreservation only. And ten SD rats underwent right carotid artery end-to-end anastomosis were used as a control group. Flow cytometry was used to test CD4+ ,CD8+ T cells in peripheral blood of recipient rats at weekly interval of 1,2, 3 weeks postoperatively. Results There is significant difference between experimental group and control group in percentages of CD4+ , CD8+ T cells and CD4+/CD8+ ( P<0.05). Conclusions 60 Co γ irradiation can keep the activity of VPHC while reduce immunogenicity of VPHC at the same time in rats.%目的 本实验应用60Co γ射线照射加液氮深低温保存大鼠同种带瓣主肺动脉(valvedpulmonary homograft conduits,VPHC),并建立大鼠VPHC颈总动脉移植模型,观察不同照射剂量对同种带瓣主肺动脉免疫原性的作用,寻找合适照射剂量,为进一步基础研究及临床应用提供理论依据.方法 1月龄封闭群Wistar大鼠50只作为供体鼠,雌雄不拘,随机分为单纯深低温保存组(实验对照组)、300 Gy照射组、600 Gy照射组、900

  19. Suppressed cytokine and immunoglobulin secretions by murine splenic lymphocytes infected in vitro with Toxoplasma gondii tachyzoites.

    Science.gov (United States)

    Guk, S M; Kook, J; Jeon, Y H; Choi, J H; Han, E T; Shin, E H; Chai, J Y

    2005-04-01

    Mechanisms of host immunosuppression after infection with Toxoplasma gondii are unclear. This study was performed to observe cytokine and immunoglobulin secretions by murine splenic lymphocytes infected in vitro with live, nonreplicating (irradiated) RH tachyzoites on stimulation with concanavalin A (Con A) or lipopolysaccharide (LPS). For lymphocyte cultivation, 3 groups were prepared: coculture with live nonirradiated tachyzoites separated by a transwell (group T), live irradiated tachyzoites without a transwell (group R), and no tachyzoites (group C). Compared with group T, groups R and C, on stimulation with Con A, revealed significantly (P lymphocytes with T. gondii tachyzoites could impair their capacity to produce cytokine and immunoglobulin secretions.

  20. 刺五加多糖对60Coγ射线照射大鼠外周血细胞的影响%Protective effect of Acanthopanax Senticosus polysaccharide on peripheral hematological cells in rats irradiated with 60 Co γ ray

    Institute of Scientific and Technical Information of China (English)

    莫琳芳; 李珂娴; 钱甜甜; 沈先荣; 何颖; 蒋定文; 刘玉明; 侯登勇; 刘琼; 陈伟; 王庆蓉

    2012-01-01

    Objective To investigate the protective effect of Acanthopanax Senticosus polysaccharide on peripheral hematological cells in rats irradiated with 60Co γ ray.Methods Sixty-three male rats were randomly divided into 7 groups,i.e.the normal control group,the irradiation control group,the WR-2721 group,the 523 group and the 3 experimental groups with high (200 mg · kg-1 · d-1 ), moderate (100 mg · kg-1 · d-1) and low (50 mg· kg-1 · d-1) doses of Acanthopanax Senticosus polysaccharide.The marrow-depressed model rats received 5 Gy 60Co γ ray whole body irradiation with a dose absorption rate of (0.388 Gy/h) except those in the normal control group.WBC,RBC and PLT in the peripheral blood were detected with hemocytometer both on the 5th day before irradiation and the 3rd and 10th days after exposure.Results When detected on the 3rd day following irradiation,WBC in the peripheral blood of the irradiated animals decreased to a level of (2.482 ±0.808) × 109 · ml-1,RBC to a level of (7.680 ±0.926) × 1012·ml-1 and PLT to a point of (360.000±43.967) × 109 · ml-1,having a rather significant decrease in the indices,when compared with those of the normal control group (P < 0.01 ). On the 10th day following irradiation,WBC in the peripheral blood of the irradiated control animals decreased to a level of (4.764 ±0.679) × 109 · ml - 1,RBC decreased to (9.004 ± 0.761 ) × 1012 · ml -1 and PLT to ( 390.000 ± 43.967 ) ×109 · ml-1,with all the indices decreasing more obviously than those of the normal control group(P < 0.01 ).Data detection before irradiation with 60Co γ ray indicated that WBC,RBC and PLT in the peripheral blood of the experimental animals elevated to various extent,when compared with those of the normal control group.Detection after irradiation showed that Acanthopanax Senticosus polysaccharide could obviously increase the levels of WBC,RBC and PLT in the peripheral blood of the irradiated animals,when compared with those of the irradiation

  1. An Experimental Study on the Effect of 60Co γ Rays Irradiation on Guinea Pig Cochlear Nucleus%豚鼠耳颞部60Coγ射线照射对耳蜗核影响的实验研究

    Institute of Scientific and Technical Information of China (English)

    钟华林; 唐安洲; 谢利红

    2012-01-01

    目的 探讨60Coγ射线照射对豚鼠耳蜗核神经元的影响.方法 48只豚鼠随机分为对照组(8只)和实验组(40只),实验组豚鼠于右耳颞部做一次性40 Gy 60Coγ射线照射后的1、4、7、14、30 d行听性脑干反应(auditory brainstem response,ABR)测试,然后处死,行耳蜗核石蜡切片HE染色及免疫组织化学染色,观察细胞形态及半胱氨酸天冬氨酸蛋白酶3(Caspase 3).对照组不予 60Coγ射线照射,行ABR测试后行耳蜗核HE染色,方法同实验组.结果 对照组ABR反应阈为29.17±1.95 dB SPL,实验组在接受60Coγ射线照射后1、4、7、14、30 d ABR阈值升高,分别为31.88±2.59、35.00±3.17、35.83±2.04、39.17±2.05、41.67±2.58 dB SPL,照射后4、7、14、30 d ABR反应阈与对照组比较差异有统计学意义(P<0.05);实验组各时间点ABR波I、II、III潜伏期及I-II、II-III、I-III波间期延长,与对照组比较差异有统计学意义(P<0.05).结论 60Coγ射线照射可导致耳蜗核损伤;Caspase3表达上调可能与耳蜗核神经元射线损伤有关.%Objective To study the effects of 60Coyrays irradiation on cochicar nucleus neurons. Methods Forty eight guinea pigs were randomly divided into control group(8 guinea pigs)and experimental group(40 guinea pigs). The experimental group animals were tested with the auditory brainstcm response at 1 , 4, 7, 14 and 30 days after irradiation of 40 Gy ,thcn the guinea pigs were sacrificed. All cochlcar nuclei tissues were made into paraffin sections. Sections were stained with hacmatoxylin and cosin and Caspasc 3 immunohistochemistry for light microscopic examination. Results ABR threshold in the control group was 29. 17 ± 1. 95 dB SPL. In experimental group, ABR thresholds were 31.88 ± 2. 59 dB SPL ,35.00 ± 3. 17dB SPL ,35.83 ± 2. 04 dB SPL, 39. 17 ± 2. 05 dB SPL, 41. 67 ±2. 58 dB SPL after 60Co irradiation 1 , 4, 7,14, 30 days groups,respectively. The differences of ABR threshold were statistically significant

  2. 60 Coγ射线辐射致LyGDI断裂对K562细胞的延迟性凋亡作用%Delayed K562 cell apoptosis promoted by cleaved LyGDI after 60Co γ-rays irradiation

    Institute of Scientific and Technical Information of China (English)

    孙华丽; 段卫明; 邵彦彦; 肖海楠; 周新文

    2010-01-01

    目的 采用不同剂量的60 Coγ射线照射人红白血病细胞系K562,探究鸟苷酸解离抑制因子-2(LyGDI)在细胞延迟性死亡中的作用以及其调控机制.方法 细胞流式仪PI单染检测细胞周期,藻红B染色观察细胞的凋亡,Western blot分析LyGDI和Rac1蛋白的表达,免疫荧光检测Rac1蛋白在细胞内的分布.结果 K562细胞被阻滞在G2/M期的百分率为71.3%,K562细胞早期凋亡率较低,8 Gy60Co γ射线照射后24 h,凋亡率为14%,呈现出延迟性的细胞凋亡;K562细胞在4 Gy的γ射线照射24 h后,可见LyGDI发生断裂,总的Rac1蛋白表达未发生明显变化,但其在细胞内的分布发生改变,Rac1转移至细胞膜上与少量核内分布,Rac1脱离LyGDI而激活.结论 LyGDI具有增加细胞延迟性凋亡的作用,其断裂使Rac1转移至细胞膜上,诱导Rac1的激活,从而促进了细胞的凋亡.%Objective To elucidate the function and regulatory mechanism of LyGDI involved delayed cell death in the human K562 cells and HL-60 cells induced by 60Co γ-rays. Methods Erythrosine B cells staining was used to count the apoptosis rate. PI staining and flow cytometry were applied to check the cell cycle. The expression of LYGDI and Rac1 was resolved by Western blot by using monoclonal antibody of LyGDI and Racl. The distribution of Racl protein in cells was observed with immunofluorescence by using the confocal microscope. Results The K562 cells showed G2/M phase arrest and the percent age was 71.3%. The apoptosis rate was very low at early post-irradiation stage in the K562 cells. The apoptosis rate was 14% in the K562 cells at 24 h post-irradiation with 8 Gy of γ-rays, and delayed cell apoptosis was present. LyGDI was cleaved in the K562 cells irradiated by 4 Gy 60 Co γ-rays after 24 hours post-irradiation. The expression of Racl protein was not altered at all, but the distribution was changed in the irradiated cells while the Racl protein moved to cell membrane and a little in cell

  3. Effects of 60 Co γIrradiation and EMS Treatment on Survival Rate and Seeding Growth of Pitaya%60Co γ射线辐照和EMS处理对火龙果成活率及幼苗生长的影响

    Institute of Scientific and Technical Information of China (English)

    邓仁菊; 范建新; 蔡永强; 高安辉; 袁启凤

    2011-01-01

    采用不同剂量的60Coγ射线辐照火龙果枝条,结果表明,枝条的成活率随辐照剂量的增加而降低,白肉火龙果枝条的适宜辐照范围为5 446.6~6 060.1 Rad,红肉火龙果枝条的适宜辐照范围为4 444.1~4 981.7 Rad,粉红火龙果枝条的适宜辐照范围为5 069.1~5 601.0 Rad;辐照处理抑制了火龙果幼苗的生长,且辐照剂量越大,对火龙果幼苗的生长抑制作用越明显.采用不同浓度的EMS溶液处理火龙果嫩芽,结果发现,芽的成活率随EMS浓度增加和处理时间延长而逐渐减小,适宜EMS诱变的浓度范围为0.34~0.41 mol/L;随EMS浓度增加和处理时间的延长,火龙果幼苗的高生长也明显受到抑制.%The cutting branches of pitaya (Hylocereus SPP. ) were irradiated by different dose 60Co γ-rays. The results indicated that survival rate of cutting branches decreased with the increase of irradiation dose, and the suitable irradiation dose rang for mutation breeding was 5 446.6 ~6 060.1 Rad of white flesh pitaya,4 444.1 ~4 981.7 Pad of red flesh pitaya, 5 069.1 ~5 601.0 Red of pink flesh pitaya. Irradiation could inhibit the growth of young seedlings, and for the higher irradiation dose, the inhibition was more significant. The shoots of pitaya were treated with different EMS concentration. The results showed that survival rate of shoot decreased with EMS concentration increased and treatment time prolonged. The suitable EMS concentration rang for mutation breeding was 0.34 ~ 0.41 mol/L, and the higher EMS concentration and longer treatment time had obvious inhibition for height growth of pitaya seedlings.

  4. Immune response against the irradiated Bothropstoxin-1 with {sup 60}Co: identification of main cytokines involved and the participation of scavengers substances; Resposta imune frente a Bothropstoxina-1 irradiada com {sup 60}Co: identificacao das principais citocinas envolvidas e a participacao de substancias scavengers

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Janaina Baptista

    2009-07-01

    Considering the effects of gamma radiation on proteins and the ability of immune system to recognize modified macromolecules, we have identified the major cytokines involved in immune response of B10.PL, BALB/c and Knockout- IFN{gamma} mice exposed to native or irradiated bothropstoxin-1 (BTHX-1), in the presence and absence of scavengers substances. In order to evaluate possible molecule structural modifications after being irradiated ({sup 60}Co gamma rays), bothropstoxin-1 was submitted to SDS-PAGE analyses. Our results indicated that irradiation process has promoted modifications in the BTHX-1 molecule, however, in the presence of scavengers and even after irradiation process, the main band of toxin was preserved (14 kDa). Sera of animals immunized with the native or irradiated toxin, in the presence or not of scavengers, were analyzed in order to quantify specific isotopes. While the native BTHX-1 induced a predominant Th2 response, the irradiated toxin apparently promoted a switch towards a Th1 pattern. The toxin, when irradiated in the presence of t-butanol, induced to a lower production of IgG2b (Th1 response) if compared with the irradiated toxin without scavengers. We also performed a Real-time PCR to quantify the expression of cytokines IFN-{gamma}, IL-2, IL-4 and IL-10 in spleen cells from mice. The cells of B10.PL and BALB/c mice immunized with native BTHX-1 and in vitro stimulated with irradiated toxin, showed higher expression of IFN-{gamma} and IL-2 (Th1 response) than the control sample. The cells of Knockout-IFN{gamma} mice immunized with native BTHX-1 showed higher expression of IL-4 (Th2 response). The cells obtained of B10.PL and BALB/c mice immunized with BTHX-1 + t-butanol, showed higher expression of IL-4 and IL-10, respectively. These facts reinforce the involvement of OH in the modulation of immune response against the irradiated toxin. (author)

  5. Activity evaluation from different native or irradiated with {sup 60} Co gamma rays snake venoms and their inhibitory effect on Leishmania (Leishmania) amazonensis; Avaliacao da atividade de diferentes venenos de serpentes, nativos ou irradiados, com radiacao gama de {sup 60} Co, quanto ao poder inibitorio do crescimento de Leishmania (Leishmania) amazonensis

    Energy Technology Data Exchange (ETDEWEB)

    Lourenco, Cecilia de Oliveira

    2000-07-01

    Cutaneous leishmaniasis is a disease, caused by Leishmania parasites, that occurs frequently in tropical and sub-tropical regions of the world. Skin lesions that could results in disfiguring aspect characterize it. The treatment is based on few drugs as antimony salts or pentamidine that are toxic with increasing resistance by the parasite. Alternative forms of disease treatment are in constant search, including natural components as snake venoms. Previous studies demonstrate that some components of snake venoms have an inhibitory effect against those parasites, including Leishmania species. Although snake venoms presented high toxicity, several methods have been described to detoxify most or some of their toxic components, with favorable results by the use of gamma irradiation. In this report we tested several native and irradiated snake venoms for inhibitory effect against Leishmania (Leishmania) amazonensis parasite and LLCMK{sub 2} mammalian cells, with enzymatic tests and electrophoresis. There are significant activity in Acanthophis antarcticus, Agkistrodon bilineatus, Bothrops moojeni, Bothrops jararaca, Hoplocephalus stephensi, Naja melanoleuca, Naja mossambica, Pseudechis australis, Pseudechis colletti, Pseudechis guttatus and Pseudechis porphyriacus, venom being inactive Pseudonaja textilis, Notechis ater niger, Notechis scutatus. Oxyuranus microlepidotus and Oxyuranus scutellatus venoms. After 2 KGy of {sup 60}Co irradiation most venom loses significantly their activity. Venoms with antileishmanial activity presented L-amino acid oxidase (L-AO) activity and showed common protein with a molecular weight about 60kDa in SDS-PAGE. These results indicate that L-AO activity in those venoms are probably related with antileishmanial effect. (author)

  6. Photoelectrocatalytic degradation of ethylene with TiO2 modified by 60Coγ-ray irradiation%利用60Co-γ射线辐照使TiO2改性后对乙烯的催化降解效果

    Institute of Scientific and Technical Information of China (English)

    郑森鸿; 叶盛英; 黄迅; 沈生文

    2013-01-01

    Horticultural products are abundant in China. However, a large amount of them were deteriorated due to the lack of appropriate storage and transport technology, resulting in a huge waste. Ethylene gas is one of the main reasons which cause the deterioration of horticultural products in storage. Nanometer TiO2 photoelectrocatalysis technology is a new technique developed in recently. TiO2, under UV light, can degrade organics such as ethylene, so it provides a potentially effective method for keeping free products. However, in practical applications, the mutual composite happens easily, which shorts the lives of the carriers and limits the application of TiO2. The only solution for this problem is to decrease the compositing rate of photoinduced electrons and the holes by modifying the nanometer-sized TiO2. Developing modified method is also a hot topic of researchers here in China and abroad. 60Co-γ ray irradiation reduction technique can modify TiO2 and make it more activity for the catalytic degradation of organics. In order to investigate the effect of TiO2, irradiated by 60Co-γray and loaded with activated carbon fibers (ACF), on photoelectrocatalytic degradation of ethylene in the environment of cold storage, the TiO2/ACF photoelecrorcatalysis materials was deposited with nano-Ag (Ag-TiO2/ACF) and irradiated by 60Co-γray. The effects of 60Co-γray irradiation modified TiO2 (10, 15, 20, 25, 30, 40 kGy) on the photoelectrocatalytic degradation rate of ethylene were investigated in a simulated cold storage environment for horticultural product. X-ray diffractometer and X-ray photoelectron spectroscopy were used to characterize the prepared TiO2. Results from X-ray diffraction showed that: the crystal size has reduced. The percent of anatase decreased from 84.97%in pure TiO2 to 82. 98%in TiO2 treated with a 40 kGy irradiation dose. Result of X-ray photoelectron spectroscopy indicated that the amount of Ti3+, hydroxyl oxygen which have better catalytic activity

  7. Preliminary research on the establishment of non-invasive model of radiation-induced oral mucositis in rats by 60 Coγ-rays irradiation%60 Coγ射线照射大鼠建立放射性口腔黏膜炎模型的初步研究

    Institute of Scientific and Technical Information of China (English)

    刘礼; 陶人川; 雍翔智; 蒋兰岚; 曾启新

    2016-01-01

    目的:建立大鼠放射性口腔黏膜炎模型,观察并分析黏膜组织炎症变化过程。方法:选择SD大鼠45只,随机分为9组:空白对照组;实验组8组均用60 Coγ射线以35 Gy剂量单次照射口鼻部。观察大鼠口腔黏膜状况,对炎症期间拒食的大鼠进行灌注流食喂养。分别于放射后1、3、5、7、10、14、21及28 d处死1组实验组大鼠,对照组于28 d处死,取口腔黏膜组织进行HE染色和光镜下观察。结果:放射后5~6 d,大鼠口腔黏膜出现红肿伴有小面积溃疡;7~8 d小溃疡逐渐融合成大面积溃疡,并持续到9~13 d;14 d开始,溃疡逐渐缩小并愈合;21~28 d溃疡完全愈合。 HE染色显示放射后第5 d,黏膜下层出现大量炎性细胞浸润,但上皮层连续完整;第7、10 d,上皮层崩解、脱落;第14 d溃疡底部可见新生肉芽组织及新生毛细血管;第21、28 d,溃疡处有新的上皮组织出现,基底层排列紧密。结论:经60 Coγ射线照射成功建立放射性口腔黏膜炎大鼠模型,炎症从5~8 d开始,第9~13 d达到高峰,14 d左右开始缓解恢复,21~28 d恢复正常。%Objective:To establish a non-invasive model of radiation-induced oral mucositis( RTOM) in rats and ob-serve the dynamic process of the occurrence,development and healing of mucosal inflammation. Methods:After randomly di-viding 45 SD rats into 9 groups,one group was maintained as a blank control group,while each rat of the other 8 groups re-ceived an irradiation of single 35 Gy dose of 60 Coγ-rays. The condition of the oral mucosal was observed everyday. Each group of experimental rats was sacrificed at the 1 st , 3 rd , 5 th , 7 th , 10 th , 14 th , 21 st and 28 th day after the irradiation respectively. However,the control group of rats were sacrificed only on the 28th day. Oral mucosa tissues of the dead rats were harvested. The samples underwent HE staining for histological

  8. Influence of natural antioxidants on lipid composition of beef burgers submitted to irradiation in {sup 60} Co source and electron beams; Influencia de antioxidantes naturais sobre o perfil lipidico de hamburgueres bovinos submetidos a irradiacao por {sup 60}Co e aceleradores de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Reginaldo Almeida da

    2007-07-01

    Radiation processing has been employed in some countries as a mean of treatment to assure microbiological safety of meat and meat products, avoiding the occurrence of food-borne disease. The ionizing radiation may cause some undesirable changes on chemistry composition of food and the lipid oxidation is one of the main reactions. In meat products processing industry, the lipid composition is directly related to nutritional and sensory quality of the product. For preventing oxidation, use of antioxidants which can be synthetic or natural, has been practically applied in some products. Currently, most attention has been given to natural antioxidants from herbs and spices like rosemary and oregano. The aim this study was to assess the antioxidant effects of either rosemary and oregano extract in beef burgers submitted to irradiation in {sup 60}Co source with dose 6, 7 e 8 kGy, electron beams with dose 3,5 e 7 kGy and storage under freeze along 0, 45 e 90 days. The results showed that rosemary extract has the major antioxidant effects when it is used on heterogeneous food matrix like beef burger, but oregano extract was better efficient to delay lipid oxidation along storage time when it is used in synergism with rosemary and/or BHT/BHA. Although to have occurred changes in the fatty acids composition it was not possible to demonstrate a straight dependence of irradiation dose and/or storage time. Sensory analysis showed that between the samples prepared with natural antioxidants, the beef burger prepared with oregano has received better scores by panelists. Irradiated beef burger prepared with rosemary has received better scores when compared to non-irradiated one. The use of spices with antioxidant activity to avoid the oxidative damage in foods that contain fats in their formulation is thought to be promising to application in food facilities. (author)

  9. 60Coγ射线半身照射对非照射区域骨髓造血组织基质细胞衍生因子1表达的影响%Influences of 60Coγray irradiation on expression stromal cell derived factor-1 in bone marrow hematopoietic tissue of non-irradiation area in left-half-body ionizing irradiated mice

    Institute of Scientific and Technical Information of China (English)

    高作文; 杨龙; 陈乐如; 娄金书; 张国强; 李开信; 程天民

    2013-01-01

    Objective To invesligale the mouse bone marrow hemalopoielic functions in non-irradiation area after irradiated by way of left-half- body. Methods The 6-8-week male Kunming strain mice were randomly divided into normal control( NC) , total-body-irradiated( TBI) , left-half-body-irradiated( LHBI) , and total-body-shield-irradia-ted( TBSI) groups. Left-half-body-irradiated group was treated with two pieces of 5 cm x 8 cm x 16 cm overlapped lead bricks shielding right-side body and irradiated with 8. 0 Gy60Coγ-ray. The leukocyte in peripheral blood and the number of bone marrow hematopoietic cells( BMHCs) were studied, the concentration of SOD, MDA in mouse serum were measured, and the expression SDF-1 in bone marrow hematopoietic tissues were observed by the Western blotting method and laser scanning confocal microscope combined with immunohistochemistry. Results In the left-half-body irradiated condition, the leucocyte in peripheral blood and the BMHCs were diminished, the concentration of MDA was increased and the SOD was decreased in the mouse serum remarkably ( compared with NC, P <0. 01) ; In non-irradiation area, the SDF-1-positive cells and the expression SDF-1 in bone marrow hematopoietic tissues were reduced significantly. Conclusion Our study suggested that the local irradiation resulted in the decrease of SDF-1-positive cells and the decline expression SDF-1 in bone marrow hematopoietic tissues in non-irradiation area, and the increase of reactive oxygen or free radicals might play an important role in the abnormal expression of SDF-1 in BMHT and the injury of hematopoietic microenvironment.%目的 探讨局部电离辐射对小鼠非照射区域骨髓造血组织基质细胞衍生因子-1(SDF-1)表达的影响.方法 将6~8周龄雄性昆明小鼠随机分为健康对照组、全身照射组、全身屏蔽照射组以及左半身照射组4组,用铅屏蔽建立半身照射模型,以8.0 Gy 60Co γ射线照射,观察小鼠外周血白细胞和骨髓有核

  10. Study on the Immune Protective Effect of Sophora japonical Water Extract on the Spleen Cells of 60Co-γ Ray Irradiated Injured Mice%槐白皮水提物对60Co-γ射线损伤小鼠脾细胞的免疫保护作用研究

    Institute of Scientific and Technical Information of China (English)

    张跃进; 董海艳; 张婵; 李安乐; 陈向敏

    2012-01-01

    目的:研究槐白皮水提物对50Co-γ射线损伤小鼠脾细胞的免疫保护作用.方法:实验分为5组,即正常(等容生理盐水)、照射对照(等容生理盐水)和槐白皮水提物高、中、低剂量(0.8、0.4、0.2 mL·kg-1)组.除正常组外其余各组给予60Co-γ射线一次性照射,照射后立即给药,每天1次,连续10d.测定小鼠脾细胞培养上清液中一氧化氮(NO)水平及脾指数.结果:槐白皮水提物中剂量组NO含量显著低于照射对照组(P<0.05);槐白皮水提物中、低剂量组脾指数显著高于照射对照组(P<0.01或P<0.05).结论:槐白皮水提物能降低射线对脾细胞的损伤,具有免疫保护作用.%OBJECTIVE: To evaluate the immune protective effect of Sophora japonical water extract on the spleen cells of 6cCo-y ray irradiated injured mice. METHODS: Mice were randomly divided into 5 groups: normal group (constant volume normal saline), irradiation control group (constant volume normal saline) ,S. Japonical water extract high-dose, medium-dose and low-dose groups(0.8, 0.4, and 0.2 mL?kg"'). All the mice were irradiated with Mco-y ray except normal group, and then S. Japonical water extract was given once a day for 10 days. And then nitric oxide (NO) level and spleen index was detected in spleen cell of mice. RESULTS: NO level of S. Japonical water extract medium-dose group was significantly lower than irradiation control group(P< 0.01), and the spleen index of S. Japonical water extract medium-doce group and low-dose groups was significantly higher than irradiation control group(f <0.01 or P<0.05). CONCLUSIONS: S. Japonical water extract can reduce the damage of the irradiated spleen cells, and have the immune protective function.

  11. Effects of gamma irradiation of the {sup 60} Co on antimicrobial action of plant extracts of bark and leaves of Schinus terebinthifolius Raddi; Efeitos da radiacao gama do {sup 60} Co sobre a acao antimicrobiana de extratos vegetais de cascas e folhas de Schinus terebinthifolius Raddi

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edvane Borges da; Santos, Gustavo Henrique Farias dos; Amaral, Ademir de Jesus [Universidade Federal da Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Lima, Jeniffer Maiza de Souza [Universidade Federal da Pernambuco (CAV/UFPE), Vitoria de Santo Antao, PE (Brazil); Xisto, Kesia; Araujo, Rosilma de Oliveira [Universidade Federal da Pernambuco (DA/UFPE), Recife, PE (Brazil). Dept. de Antibioticos

    2014-07-01

    This study aimed to evaluate the potential for antimicrobial activity in vitro of extracts of bark and leaves of S. terebinthifolius treated with {sup 60}Co gamma radiation. 5,0 doses were used; 7.5 and 10 kGy, being held non-irradiated controls. To determine the antimicrobial activity was applied to the disc diffusion technique to evaluate the diameter of the inhibition zones against Gram-positive bacteria, gram-negative bacteria, alcohol-acid-resistant and yeast. Antimicrobial activity was considered significant for halos ≥ 15 mm. The results indicate an intensification of antimicrobial action of bark extracts, the 5.0 kGy, against S. aureus. Was held the micro dilution in broth to determine the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of peels extracts, compared to eight clinical isolates of S. aureus. The MBC values showed that ionizing radiation did not produce the increased of anti bacteriostatic action of S. terebinthifolius, but the results indicated that S. terebinthifolius bark extracts can be used as an antimicrobial agent and ionizing radiation as an important alternative in this conservation feature.

  12. Research of Effect of 60Co γ-ray Irradiation on Cell Cycle of SMMC, 7721 Tumor Cell with Flow Cytometery

    Institute of Scientific and Technical Information of China (English)

    DangBingrong; MaQiufeng; GaoQingxiang; LiWenjian; HaoJifang; XieYi; GuoChuanling

    2003-01-01

    The resultsMost researchof cell cycle play an important role in resear, ching tumor occurrence, development and treatment. results show that malignant grade and pharmic sensitivity of tumor are relative to cell cycle. The sensitivity of medications is different to different phases of cell cycle of tumor. In general, the cell of M are more sensitivity. On the side, different medications have different action in different cell cycle. The irradiation can change cell cycle proccss and can induce the pattern of changes in cell cycle. For cxamplc, G1 arrest, G2 arrest and S arrest. So, thc research rcsults of tumor cell cycle in different irradiation have not only biological means but also realistic means for selecting chemical therapy medication after radiotherapy.

  13. 60Co γ射线辐照预处理对甘薯热风干燥特性的影响%INFLUENCE OF 60Co γ IRRADIATION PRE-TREATMENT ON CHARACTERISTICS OF HOT AIR DRYING SWEET POTATO SLICES

    Institute of Scientific and Technical Information of China (English)

    江宁; 刘春泉; 李大婧; 刘霞; 严启梅

    2012-01-01

    The influences of irradiation, hot air temperature and thicknesses of the slices on the characters of dehydration and surface temperature of 60Co γ-rays irradiated sweet potato were investigated. Meanwhile, microscopic observation and determination of water activity of irradiated sweet potato were conducted. The results show that the drying rate and the surface temperature rised with the increasing of irradiation dose. When the dry basis moisture content was 150% , the drying rate of the samples were 1.92, 1.97, 2.05, 2.28, 3.12%/min while the irradiation dose were 0, 2, 5, 8, 10kGy, and the surface temperature were 48.5℃ , 46.3℃ , 44.5℃, 42.2℃, 41.5℃ , respectively. With higher air temperature and thinner of the sweet potato slices, the dehydration of the irradiated sweet potato slices were faster. The drying speed of sweet potato slices at 85℃ was 170min faster than that of 65℃. The drying speed of 7mm sweet potato slices was 228min faster than that of 3mm sample. The cell wall and the vacuole of the sweet potato slices were broken after irradiation, and its water activity increased with the inorease is radiation dose. The water activity of the irradiated samples were 0. 92, 0. 945, 0. 958, 0. 969, 0. 979 with the irradiation doses of 0, 2, 5, 8, 10kGy, respectively. The hot air drying rate, surface temperature and water activity of sweet potato are significantly impacted by irradiation. The conclusion provids a theoretical foundation for further processing techonology of combined radiation and hot air drying sweet potato.%采用60Coγ射线对甘薯进行辐照预处理,考察辐照、热风温度和切片厚度对其干燥特性和表面温度的影响,同时对不同剂量辐照的甘薯样品进行了显微观察和水分活度测定。结果表明,甘薯的干燥速率和表面温度随着辐照剂量的升高而升高。当干基含水率为150%时,辐照剂量为0、2、5、8和10kGy的样品干燥速率分别为1.92、1.97、2.05、2.28和3

  14. Thermal stability of formulations of PVC irradiated with {gamma} of {sup 60}; Estabilidad termica de formulaciones de PVC irradiadas con {gamma} de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Martinez P, M.E.; Carrasco A, H. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: memp@nuclear.inin.mx; Castaneda F, A.; Benavides C, R.; Garcia R, S.P. [CIQA, 25100 Saltillo, Coahuila (Mexico)

    2004-07-01

    The industry of cables and wires frequently use cable isolations with base of formulations of PVC, in those that stabilizer has usually been used with the help of heavy metals, as the lead, which is toxic. To solve the problem, from the 2002 one has come studying in combined form in the National Institute of Nuclear Research ININ and the Center of Investigation in Applied Chemistry CIQA, the modifications induced by the radiation in formulations with the help of vinyl poly chloride PVC. In these formulations, prepared with cross linking agent, plastifying industrial grade, stuff and non toxic stabilizers of calcium estearate and zinc industrial grade, it is sought to replace the stabilizer of Pb. For this were irradiated it test tubes of PVC with gamma radiation of cobalt 60 to three different dose in atmospheres of air and argon. Later it was determined their thermal stability at different times of heating and it was measured the Young modulus by means of thermo mechanical analysis. Those results obtained together with other techniques of characterization suggest that the irradiated proposed formulation can substitute the one stabilized with lead. (Author)

  15. Effect of ethanolic extract of propolis on cell viability of chinese hamster ovary cells (CHO-K1) irradiated with {sup 60}CO gamma-rays using differential staining technique

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Marcos P.M. de; Castro, Renato F. de; Okazaki, Kayo; Vieira, Daniel P., E-mail: dpvieira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The objective of present study was to assess the effect of Brazilian propolis (AF-08) on CHO-K1 cells irradiated with {sup 60}Co, through the differential staining technique, using acridine orange and ethidium bromide. The cells were pre-incubated with different concentrations of propolis (50, 100 and 200 μg/mL) for 24h and irradiated with 5 Gy, analyzed at 24 and 48h after exposure. This technique is based on the cell capacity to incorporate fluorescent DNA dyes, where the viable (green), apoptotic (orange/yellow) and necrotic (red) cells can be identified through fluorescence microscopy. Digital high-resolution images were acquired from at least 5 visualization fields, and cells were analyzed using ImageJ and Flowing software. This approach permitted to analyze a large number of cells/sample with the time reduction, much easier and faster, proportioning more statistical power of the technique. The treatment with propolis only was not cytotoxic at 24 and 48h, except for the higher concentration of 200 μg/mL associated or not with radiation, increasing apoptotic and mainly necrotic cells (p<0.001). The data showed a promising use of propolis as well as technique used, pointing out that 200 μg/mL of propolis was cytotoxic, but at lower one (50 μg/mL) presented a radioprotective effect in irradiated CHO-K1 cells. (author)

  16. Efeito da irradiação (60Co na frequência fúngica de amendoim in natura em função do tempo de prateleira Gamma-irradiation effect (60Co in fungi frequency of peanut in natura and after storage

    Directory of Open Access Journals (Sweden)

    Guilherme Prado

    2006-10-01

    Full Text Available Foi verificado o efeito da irradiação gama (60Co na capacidade de destruir a microbiota fúngica, em amendoim em grão, cultivar Tatu Vermelho, da safra 2003 (segundo semestre. Os grãos de amendoim, após a irradiação, foram mantidos à temperatura ambiente em embalagem plástica comercial, durante 180 dias. Para a determinação da porcentagem fúngica foi utilizada a técnica do plaqueamento direto utilizando o meio Ágar Dicloran Rosa de Bengala Cloranfenicol (DRBC, desinfetando ou não os grãos com solução de hipoclorito de sódio. Em grãos de amendoim irradiados e desinfetados externamente, observou-se redução da infecção fúngica a 5 kGy e destruição total de fungos a 10 kGy, após 180 dias de armazenamento à temperatura ambiente. Em grãos irradiados e não desinfetados externamente foram verificados, em função do tempo de armazenamento, aumento da população de fungos com a dose de 1 kGy, redução com a dose de 5 kGy e eliminação total com a aplicação de 10 kGy. A irradiação gama, na dose de 10 kGy ou superior, demonstrou ser um processo eficaz na redução da microbiota fúngica de amendoim em grão, cultivar Tatu Vermelho.Gamma-irradiation effect was verified on the capability of destroying the mycoflora of peanuts grain, Tatu Vermelho cultivar, 2003 crop (second semester. The peanuts grains, after irradiation, were kept at room temperature in plastic bags during 180 days. To determine the percentage of fungi, the direct plating technique was used and the grains were plated out on mycological media dicholoran rose bengal chloranphenicol (DRBC, being desinfected or not with sodium hypochlorite solution. Irradiated and desinfected peanuts was observed a reduction of fungi infection at 5 kGy and total fungi destruction at 10 kGy, after 180 days in storage at room temperature. Irradiated and non desinfected grains showed a increase of fungi population with 1 kGy dose, reduction with 5 kGy dose and total

  17. Effects of 60Coirradiation on photosynthetic pigments and gas exchange parameters of the leaves of watermelon%60Co-γ辐射种子对西瓜幼苗叶片光合色素及气体交换参数的影响

    Institute of Scientific and Technical Information of China (English)

    李金霞; 李玉明; 陈菁菁; 韩国君; 陈年来

    2015-01-01

    通过对3类不同质量(包括12个品种)的西瓜干种子进行不同剂量的辐射处理,研究了60Co-γ射线辐射对西瓜幼苗叶片光合色素及气体交换参数的影响.结果表明:60Co-γ射线辐射后,西瓜幼苗叶片叶绿素a和类胡萝卜素的含量随辐射剂量的增加呈现先增大后减小的趋势,叶绿素b的含量随辐射剂量的增加总体呈现出逐渐减小的趋势;气体交换参数Gs、Pn、Tr随着辐射剂量的增加而减小.不同质量西瓜种子对60Co-γ辐射的敏感性表现为大种子材料>小种子材料>中等种子材料;不同种质类型西瓜种子对60Co-γ辐射的敏感性表现为杂交种子品种>常规种子品种.

  18. Effects of γ-ray total body irradiation from a 60Co source on expression level of intrathymic forkhead box protein N1 in mice%60Coγ射线全身照射对小鼠胸腺中叉状头转录因子N1表达水平的影响

    Institute of Scientific and Technical Information of China (English)

    孙玉琦; 武育菁; 刘洁; 潘彬; 徐开林

    2016-01-01

    delta样配体(DLL)4、自身免疫调节蛋白(Aire)与骨形成蛋白(BMP)4 mRNA相对表达水平相比,差异均有统计学意义(CCL25 mRNA相对表达水平:11.2±1.5、11.4±1.2、1.0±0.1,DLL4 mRNA相对表达水平:7.3±0.9、6.3±0.3、1.0±0.1,Aire mRNA相对表达水平:5.1±1.0、5.0±0.1、1.0±0.1,BMP4 mRNA相对表达水平:4.4±1.4、3.6±0.5、1.0±0.1;F=148.862、197.667、73.911、21.471,P=0.000、0.000、0.000、0.000);3组中Foxn1上游基因同源框蛋白(Hox)a3 mRNA相对表达水平相比,差异却无统计学意义(1.4±0.4、0.8±0.3、1.0±0.1相比;F=5.368,P=0.221).与对照组相比,L-TBI 5 d组中Foxn1下游基因CCL25、DLL4与Aire的mRNA相对表达水平均显著增高(p=0.000、0.000、0.000);SL-TBI 5 d组中CCL25、DLL4与Aire mRNA相对表达水平亦显著增高(P=0.000、0.000、0.000).同时,与对照组相比,L-TBI 5 d组、SL-TBI 5 d组中BMP4mRNA相对表达水平存在一定程度的增高,且差异亦有统计学意义(P=0.000、0.000).结论 60C0γ射线TBI可导致小鼠胸腺中Foxn1mRNA表达水平增高,Foxn1表达水平上调及其相关基因表达水平的变化与胸腺受损程度的关系密切.%Objectives To explore the influence of γ-ray total body irradiation (TBI) from a 60Co source induced mice thymus injury on expression levels of forkhead box protein N (Foxn) 1 and related genes,and to analyze the correlation between expression levels of Foxn1,related genes and thymus injury.Methods Sixty five male C57BL/6 mice were chosen as subjects during November and December 2014.Inclusion criteria for choosing mice:all these mice are 6-8 weeks old specific pathogen free (SPF) animals,and weighting between 18.0-21.0 g.Thirty-five mice were randomly devided into 4 groups:① Lethal total body irradiation (L-TBI) 5 d group (n=10),mice received a total dose of 7.5 Gy γ-ray TBI from a 60Co source;② Sublethal total body irradiation (SL-TBI) 5 d group (n=10),mice received a total dose of 5.5 Gy TBI;③SL-TBI 24 d group (n =10),mice

  19. Humoral immune response of C57Bl/6j and BALB/c mice immunized with irradiated tachyzoites of Toxoplasma gondii RH strain and oral challenge with ME-49 strain

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Galisteo Junior, Andres [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Centro de Biotecnologia; Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil). Lab. de Protozoologia; E-mail: galisteo@usp.br; Zorgi, Nahiara Esteves; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil). Lab. de Protozoologia; Alves, Janaina Baptista; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Centro de Biotecnologia; Hiramoto, Roberto Mitsuyoshi [instituto Adolfo Lutz, Sao Paulo, SP (Brazil)

    2007-07-01

    Toxoplasmosis, a prevalent widespread infection in man and animals, is mainly transmitted by oral route, through ingestion of oocysts from water and food contaminated with cat feces or infected animal tissue cysts in undercooked meat. Vaccine development implies in effective intestinal immunity, the first site of parasite entry. Radiation (255 Gy/{sup 60}Co) sterilized T. gondii RH strain tachyzoites (RST) induced significant protection when parentally administered, similar to chronically infected and acute disease protected animal. We study the humoral immune response in C57Bl/6j and BALB/c mice immunized with 10{sup 7} RST, by oral (with aluminium hydroxide 3%) or parenteral 3 biweekly administrations. T. gondii antigens specific ELISA for IgG, IgA, IgG1, IgG2a and IgG2b detection was performed in weekly blood samples during immunization. Also we evaluate of the intestinal epithelial of immunized mice the integrity of the radiated parasites by electronic microscopy. After 2 weeks, immunized and control animals were challenged with 10 cysts of ME-49 strain p.o. Protection was determined at the 30th day by brain cyst counting. As it was possible to observe in the intestinal mucosal, the aluminium hydroxide seems to maintain unchanged the parasite morphology and its mechanisms of invasion, probably due to keeping it safe from extreme pH condition of stomach. All immunized groups presented significant protection when challenged with ME-49; however, BALB/c mice showed better protection levels, with only one positive animal on brain microscopic analysis. IgG production in the serum of the animals was higher in groups immunized by i.p route, however, IgA and IgG1 levels were higher in BALB/c mice immunized by oral route. This higher protection found in BALB/c group could probably also be related to the Th2 response, demonstrated by higher IgG1 levels. All these data provide insights in oral immunization schedules for toxoplasmosis prevention, suggesting that oral

  20. Study of the {sup 60}Co speciation in the aqueous radioactive waste of the la Hague nuclear reprocessing plant; environmental behaviour after discharges in the waters of the channel; Etude de la speciation du {sup 60}Co dans les effluents de l'usine de retraitement de combustibles irradies de la Hague; devenir apres rejet dans les eaux de la Manche

    Energy Technology Data Exchange (ETDEWEB)

    Gaudaire, J.M

    1999-07-01

    {sup 60}Co is produced as an activation product and is present in the low-level aqueous radioactive waste released from the La Hague plant. At present, the concentration in the sea (non filtered at 0.45 {mu}m) at the Goury site are close to or even below, the detection limit: 0.2 mBq.l{sup -1}. The {sup 60}Co speciation depends on the type of effluent considered: in the effluent A ('active'), the cobalt is in the form of a stable trivalent complex; in the effluent V (to be checked), the cobalt is in majority (50% of the activity release) in the form of particles (>0.45 {mu}m), and then in the form of two soluble species: ionic divalent (Co{sup 2+}) and some stable complexes. The evolution of the reprocessing techniques used does not affect the speciation. So, since the nuclear reprocessing plant started at the La Hague plant in 1966, the chemical species discharged in the sea shows time variation related to the evolution of the type of effluent discharged. Thus, since 1994, the particles of cobalt are the main species discharged in the Channel (the V effluents represent more than 85% of the total {sup 60}Co activity released). The effect of instantaneous dilution into the marine conditions involving a variation of pH, oxido-reduction, ionic strength, a gradient of salinity, does not interfere with the evolution of the chemical species discharged. Nevertheless, during the discharge of the V effluent, the main constituents of the sea water (Mg{sup 2+} and Ca{sup 2+}) go through a precipitation. This comes with the coprecipitation of the ion Co{sup 2+} and with the particles of cobalt (complexes are not affected), and it can be responsible for an increase in the concentration in the particles. The chemical behaviour of the cobalt in the Channel is different from those of conservative element such as antimony. The ionic cobalt and the particles have a small dispersion in the water (cobalt has a very high particle/dissolved distribution factor, it is a non

  1. EFFECT OF LOW DOSE IRRADIATION OF 60Coγ-RAYS ON SEED GERMINATION, SEEDLING GROWTH AND ENZYMES ACTIVITY OF Lactuca sativa%~(60)Coγ射线低剂量辐照对生菜种子萌发、幼苗生长及酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    刘秀清; 章铁

    2012-01-01

    The seeds of Lactuca sativa were irradiated by different doses (10,20,30,40,50Gy) of 60Co Lactuca sativa ; 60 Co γ-rays ; low dose irradiation ; enzyme activity ; germination- rays. The effects of low dose irradiation on seed germination, seedling growth and enzymes activity were investigated. The results indicated that low dose irradiation could promote germination rate, germinating viability, germination rate in the field, root length and height of seedling. The suitable dosage for low dose irradiation for Lactuca sativa was 30Gy. POD activity after irradiation treatment in the range of 10 to 50Gy and CAT activity after irradiation treatment in the range of 20Gy to 40Gy was lower than that of control.%用不同剂量(10、20、30、40和50Gy)60Coγ射线辐照生菜种子,研究其对种子萌发,幼苗生长和酶活性的影响。结果表明,低剂量辐照可显著提高生菜种子的发芽率、发芽势、田间出苗率、幼苗高度和主根长度,对种子萌发和幼苗生长有一定的促进作用。综合考虑各苗期性状指标初步确定生菜低剂量辐照的适宜剂量为30Gy。在所试剂量范围内辐照处理的POD活性均低于对照;在20~40Gy剂量范围内辐照处理的CAT活性与对照相比也有所降低。

  2. Study of the effect of gamma irradiation ({sup 60} Co) on the quality of sugar cane spirit and on the cask of maturation; Estudo do efeito da irradiacao gamma ({sup 60} Co) na qualidade da cachaca e no tonel de envelhecimento

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Mariana Branco de; Horii, Jorge; Alcarde, Andre Ricardo [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept.de Agroindustria, Alimentos e Nutricao]. E-mails: jhorii@esalq.usp.br; aralcard@esalq.usp.br

    2006-10-15

    The ageing or maturing process of drink improves the sensorial characteristics of the product making it a qualified drink with higher economical value. The traditional maturing method of drinks involves their interaction with wood and irradiation can accelerate this ageing process. Sugar cane spirit and oak barrels with a 20 L capacity were treated using gamma irradiation (150 Gy). Physical-chemical and chromatographic analyses were constantly performed for 390 days during the drink ageing period. The sugar cane spirit and barrel irradiation did not change most volatile components of the same type coefficient such as volatile acidity, esters, superior alcohols and furfural throughout the 390 days. There is evidence, however, that some component parameters like aldehydes, tannin, color and copper concentration are in some way influenced resulting in partial acceleration of the ageing or maturing process. At the end of the ageing period, a sensorial analysis was made using 30 non-trained people who tasted the drink. The ageing process acceleration was confirmed by the sensorial evaluation, where the irradiated sugar cane spirit and/or barrel had higher approval regarding all parameters analyzed (scent, flavor and appearance). (author)

  3. Estudo do efeito da irradiação gamma (60CO na qualidade da cachaça e no tonel de envelhecimento Study of the effect of gamma irradiation (60co on the quality of sugar cane spirit and on the cask of maturation

    Directory of Open Access Journals (Sweden)

    Mariana Branco de Miranda

    2006-12-01

    Full Text Available O processo de envelhecimento ou maturação das bebidas proporciona uma melhora nas características sensoriais da cachaça, tornando-a de qualidade superior e de maior valor econômico. O método tradicional de maturação de bebidas é sua interação com madeiras, sendo que a irradiação pode acelerar este processo de envelhecimento. A cachaça e os tonéis de carvalho de 20 L de capacidade foram submetidos à irradiação gama (150 Gy. Análises físico-químicas e cromatográficas foram realizadas periodicamente ao longo de 390 dias do período de envelhecimento da bebida. A irradiação da cachaça e do tonel não alterou a maioria dos componentes voláteis do coeficiente de congêneres como acidez volátil, ésteres, álcoois superiores e furfural durante os 390 dias. Há evidências, entretanto, de que os parâmetros de alguns componentes como aldeídos, taninos, cor e teor de cobre são de alguma forma influenciados, resultando em aceleração parcial do processo de maturação ou envelhecimento. Ao final do período de envelhecimento, foi feita uma análise sensorial com 30 provadores não treinados. A aceleração do processo de envelhecimento foi confirmada pela avaliação sensorial, e a cachaça e/ou tonel irradiados receberam maior indicação de aprovação em todos os parâmetros analisados (aroma, sabor e aparência.The ageing or maturing process of drink improves the sensorial characteristics of the product making it a qualified drink with higher economical value. The traditional maturing method of drinks involves their interaction with wood and irradiation can accelerate this ageing process. Sugar cane spirit and oak barrels with a 20 L capacity were treated using gamma irradiation (150 Gy. Physical-chemical and chromatographic analyses were constantly performed for 390 days during the drink ageing period. The sugar cane spirit and barrel irradiation did not change most volatile components of the same type coefficient such

  4. Photocatalysis degradation of ethylene with γ-ray irradiated modified silver-doped TiO2%60Co-γ辐照改性银掺杂纳米TiO2及光催化降解乙烯

    Institute of Scientific and Technical Information of China (English)

    沈生文; 叶盛英; 宋贤良; 李明波; 方一超

    2012-01-01

    为了解60Co-γ射线辐照且以活性炭纤维(ACF)为载体所负载TiO2的半导体材料(TiO2/ACF)对光催化降解冷藏环境中乙烯的影响,该文拟采用60Co-γ辐照制备纳米Ag沉积的TiO2/ACF (Ag-TiO2/ACF)光催化材料,在模拟园艺产品的冷藏环境中,进行了3种不同膜的光催化降解乙烯效果的研究,并利用场发射扫描电镜(FESEM)、透射电子显微镜(TEM)、X射线衍射仪(XRD)对所制备的光催化材料进行相关的表征分析.结果表明:在加入分散剂聚乙烯吡咯烷酮后,60C0-γ辐照能使Ag颗粒较好地负载在TiO2上,TiO2均匀分散在ACF膜上而不发生团聚,且TiO2颗粒晶相改变、尺寸变小,有助于提高Ag-TiO2/ACF的催化效率.Ag-TiO2/ACF光催化降解乙烯的效果用一级动力学速率方程描述;经辐照制备的Ag-TiO2/ACF薄膜比未辐照的TiO2/ACF和辐照的TiO2/ACF薄膜光催化降解乙烯的反应速率常数分别提高了44%和37%.研究结果为TiO2光催化技术的进一步的应用提供了参考.%In order to investigate the effect of TiO2 irradiated by 60Co-y ray and loaded by activated carbon fibers on photocatalytic degradation of ethylene in the environment of cold storage, the TiCVACF photocatalytic materials deposited with nano-Ag (Ag-TiO2/ACF) irradiated by 60Co-y ray were prepared, and effects of three different films on the photocatalytic degradation rate of ethylene were investigated in the simulated cold storage environment for horticultural products. Environmental Scanning Electron Microscope (ESEM), Field Scanning Electron Microscope (FESEM) and X-ray diffractometer (XRD) were used to analyze the characterizations of the prepared Ag-TiO2/ACF. Results showed that: 60Co-y ray could make Ag load on the surface of TiO2 well and TiO2 could be dispersed on the ACF uniformly after adding the dispersant of polyethylene pyrrolidone, which could effectively prevent the aggregation of the nano-particles. The average particle size of TiO2

  5. 60Coγ射线对生理盐水和玉米中黄曲霉孢子的辐照效应研究%Irradiation effect of 60Co gamma ray on Aspergillus flavus spores in normal saline and maize

    Institute of Scientific and Technical Information of China (English)

    钟凯; 高翔; 计融

    2011-01-01

    目的 研究γ射线对黄曲霉孢子辐照效应.方法 两种介质中不同浓度黄曲霉孢子经不同剂量辐照后进行菌落计数,计算D值和理论最小杀灭剂量,并实验验证实际最小杀灭剂量.结果 生理盐水中高浓度孢子D值0.39kGy,最低杀灭剂量2.5kGy,低浓度孢子D值0.47kGy,最低杀灭剂量1.5kGy;玉米中高浓度孢子D值为0.67kGy,最低杀灭剂量3.0kGy,低浓度孢子D值为0.72kGy,最低杀灭剂量2.0kGy.结论 3.0kGy可用于粮食中黄曲霉的杀灭.%Objective To observe irradiation effect of gamma ray on Aspergillus flavus spores.Methods Aspergillus flavus spores of different concentration were prepared on two media and were exposed to gamma ray.D10 values and theoretical minimal sterilizing doses were calculated by colony counting results.Actual minimal sterilizing doses were verified according to theoretical dose.Results D10 value and minimal sterilizing dose of high concentration spore in normal saline were 0.39kGy and 2.5kGy.Those of low concentration spore in normal saline were 0.47kGy and 1.5kGy.D10 value and minimal sterilizing dose of high concentration spore in maize were 0.67kGy and 3.0kGy.Those of low concentration spore in maize were 0.72kGy and 2.0kGy.Conclusion 3.0kGy may be suitable for grain processing to sterilize Aspergillus flavus.

  6. Microstructural study of Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-x}/Ag samples irradiated with {sup 60}Co {gamma} rays at high doses

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, R. [Programa de Postgrado en Fisica de Materiales, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Apartado Postal 2681, CP 22800, Ensenada, BC (Mexico); Galvan, D.H. [CECIMAC-UNAM, Apartado Postal 2681, CP 22800, Ensenada, BC (Mexico); Adem, E. [Instituto de Fisica-UNAM, Apartado Postal 20-364, CP 01000, Mexico DF (Mexico); Bartolo-Perez, P. [CINVESTAV-IPN Unidad Merida, Departamento de Fisica Aplicada, Merida, Yucatan (Mexico); Maple, M.B. [Physics Department and Institute for Pure and Applied Physical Sciences, La Jolla, CA (United States)

    1998-06-01

    We have investigated the damage induced by irradiation in Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-x} silver added samples. The samples were prepared with 0 and 6.5 wt% of silver and irradiated by high-energy {gamma} irradiation (50-150 Mrad). The roles of silver and dosage irradiation are discussed in terms of their effects on microstructure, crystallinity, critical temperature (T{sub c}) and zero-resistance temperature (T{sub 0}). After irradiation, T{sub c} decreased while the room-temperature electrical resistance increased by a factor of 8 for some of the samples. The difference in T{sub 0} between irradiated and non-irradiated YBCO samples was of the order of 10 K. We have found that the difference is bigger for silver-added samples. We have also observed several changes in diffraction patterns of YBCO and YBCO-silver samples. SEM images, EDS and XPS analysis showed that silver resided inside the grains as single atoms and as metallic clusters. The relative concentrations of the elements in samples were quantified by Auger electron spectroscopy. The values showed a gradual increase for radiation doses ranging between 0 and 100 Mrad. For doses up to 100 Mrad, J{sub c} decreased because of the weak-link breakage induced by high doses of {gamma} rays. (author)

  7. 60Co辐射交联乙烯-醋酸乙烯酯共聚物/氢氧化镁复合材料的热、力学及阻燃性能研究%Thermal, mechanical and flame-retardant properties of crosslinked ethylene vinyl-acetate copolymer/magnesium hydroxide blends by 60Co irradiation

    Institute of Scientific and Technical Information of China (English)

    李振中; 何伟; 张文熊; 瞿保钧

    2007-01-01

    Three types of ethylene vinyl-acetate copolymer (EVA)/magnesium hydroxide (MH) blends were crosslinked by 60Co γ-irradiation in the presence of trimethylolpropane triacrylate. The influences of irradiation dose on the crosslinking degree and thermal, mechanical and flame retardant properties of EVA/MH blends were studied through the measurements of gel content, Vicat point, limiting oxygen index (LOI), UL-94, tensile testing and the thermogravimetric analysis (TGA). The test results show that the EVA/MH blend with higher vinyl-acetate content in EVA is easier to be crosslinked. The thermal distortion resistance, mechanical and flame-retardant properties of EVA/MH blends are obviously improved by 60Co irradiation. The TGA shows that the thermal stabilities of EVA/MH blends are apparently affected by 60Co γ-irradiation.%以三羟甲基丙烷三丙烯酸酯为交联助剂,以60Co为辐射源,对三种不同醋酸乙烯酯(Vinyl-acetate,VA)含量的乙烯-醋酸乙烯酯共聚物(Ethylene vinyl-acetate copolymer,EVA)/氢氧化镁混合材料进行了辐照交联.通过对凝胶含量、维卡软化点、氧指数、UL-94垂直燃烧和拉伸性能的测试及热重分析,研究了辐照剂量对EVA/氢氧化镁交联体的交联度、热性能、力学性能和阻燃性能的影响.研究结果表明:VA含量高的EVA/氢氧化镁交联体更容易产生辐射交联;辐照交联后的EVA/氢氧化镁复合材料的抗热变形能力、力学性能及阻燃性能都获得明显改善.热重分析结果表明,60Co辐射明显影响EVA/氢氧化镁的热氧稳定性.

  8. Sorption of {sup 60} Co on inorganic solids; Sorcion de {sup 60} Co en solidos inorganicos

    Energy Technology Data Exchange (ETDEWEB)

    Granados C, F.; Bulbulian G, S. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Mardel V, B. [UAM-I, 09340 Mexico D.F. (Mexico)

    2003-07-01

    The behavior of sorption of the {sup 60} Co in aqueous solution under static conditions to different values of pH of the aqueous solution (1, 3, 5, 7, and 10) on MgO, MnO{sub 2}, SnO, TiO{sub 2}, activated carbon and calcinate hydrotalcite was investigated. It was found that the best sorbents of the {sup 60} Co was the MnO{sub 2}, activated carbon and TiO{sub 2} whose sorption was incremented when increasing the pH value of the aqueous solutions, in the one case of the hydrated oxides, the {sup 60} Co interacted with the electrically charged surface of the sorbents that depends on the pH of the solution and of the point of zero charge (zpc) of the sorbent. (Author)

  9. Effects of {sup 60}Co radiation on bothropstoxin-1 structure

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, P.J.; Nascimento, N.; Rogero, J.R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Div. de Radiobiologia; Byrne, M.; Smith, L.A. [United States Army Medical Research, Frederick, MD (United States). Inst. of Infectious Diseases. Toxinology Div.

    2000-07-01

    Gamma radiation is able to detoxify snake venoms and toxins without significantly affecting their immunogenic properties. This method has been successfully employed to attenuate toxins for antisera production without inducing toxic effects in animals undergoing immunization. However, the mechanism of attenuation is not fully understood and much work remains at the molecular level in order to further characterize the effects of radiation on these proteins. The present study was undertaken to evaluate structural modifications following irradiation of bothropstoxin-1 (bthTx-1), a myotoxin from Bothrops jararacussu. It is believed that the functional form of the toxin is a homodimer with the binding affinity provided by electrostatic and hydrophobic interactions. Purified BthTx-1 was irradiated with 500, 1000 and 2000 Gy of {sup 60}Co gamma radiation. The irradiated and native toxins were compared by mass spectrometry, circular dichroism (CD) and tryptophan fluorescence quenching, results suggest that the monomer-monomer interactions are hydrophobic in nature. No significant differences were observed between the two forms of the toxin by CD spectral interpretation. However, significant losses of secondary structure could be observed when the native and irradiated BthTX-1 were compared after disulfide bond reduction. Fluorescence data indicates that the solvent accessibility of Trp 77 has been modified, which may explain the differences in quaternary structure. (author)

  10. Manufacture of Single ~(60)Co Source Irradiation Facility

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Reference radiation filed produced by isotope source is necessary for calibration of radiation dose meter. According to the GB/T 12162.1-2002 "X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining

  11. Tachyzoites of Toxoplasma gondii irradiated with 255 Gy induces decrease of cysts and cerebral lesions in mice challenged with cysts of ME-49; Taquizoitos de Toxoplasma gondii irradiados com 255 Gy induzem diminuicao de cistos e lesoes cerebrais em camundongos desafiados com cistos da cepa ME-49

    Energy Technology Data Exchange (ETDEWEB)

    Hiramoto, Roberto Mitsuyoshi; Galisteo Juniorm Andres Jimenez; Nascimento, Nanci do; Andrade Junior, Heitor Franco de [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Biologia Molecular]. E-mail: rmhiramoto@bol.com.br; hfandrad@usp.br

    2002-07-01

    Toxoplasmosis can cause ocular lesions in normal individuals and several diseases in foetus, HIV infection and transplants. Toxoplasma gondii has a complex life cycle, involving cats, as the definitive host, and warm blood species, as intermediated hosts. The infection occurs by ingestion of food and water contaminated with infected cat faeces, contaminated milk and cheese or raw and undercook meat of the intermediated hosts. To date, there is no commercial vaccine of use in humans. In this work, tachyzoites of T. gondii RH strain were irradiated with 255 Gy and inoculated in C57Bl/6j mice (3 doses, biweekly), after mice were challenged with 1, 5, 10, 20 and 25 cysts of ME-49 by oral gavage. The lesions and cysts in the brain were analyzed in all mice, after 4-week post infection. The mortality was 20% in control mice (ME-49 cysts only) and not one in immunized mice. The number of cysts was high in the control group, but low in immunized 255 Gy mice (n<100). Immunized mice showed less cerebral pathology and necrosis foci. Ionizing radiation is an important tool in the study toxoplasmosis and vaccine development. (author)

  12. Evaluation of the radio modifier effect of propolis on chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60-CO; Avaliacao do efeito radiomodificador da propolis em celulas de ovario de hamster chines (CHO-K1) e em celulas tumorais de prostata (PC3), irradiadas com CO-60

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Geyza Spigoti

    2011-07-01

    In the last decades, it has been given a great interest to investigations concerning natural, effective, nontoxic compounds with radioprotective potential together with the increasing utilization of different types of ionizing radiation for various applications. Among them propolis, a resinous compound produced by honeybees (Apis mellifera), has been considered quite promising, since it presents several advantageous biological characteristics, i. e., anti-inflammatory, antimicrobial, anticarcinogenic, antioxidant and also free radical scavenging action. The purpose of the present study was to evaluate the effect of Brazilian propolis, collected in the State of Rio Grande do Sul, on Chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with {sup 60}Co {gamma} radiation. For this purpose, three interlinked parameters were analyzed: micronucleus induction, cell viability and clonogenic death. The choice of these parameters was justified by their biological significance, in addition to the fact that they are readily observable and measurable in irradiated cells. The cytogenetic data obtained showed a radioprotective effect of propolis (5-100 {mu}g/ml) in the induction of DNA damage for both cell lines, irradiated with doses of 1 - 4 Gy. The cytotoxicity assay, however, showed a prominent antiproliferative effect of propolis (50 - 400{mu}/ml) in PC3 cells irradiated with 5 G{gamma}. The survival curves obtained were adequately fitted by a linear-quadratic model, where the {alpha} coefficient was higher in CHO-K1 cells. Concerning the clonogenic capacity, PC3 cells were more radiosensitive than CHO-K1 cells at the higher doses of the survival curve. Propolis at the concentrations of 30 - 100 {mu}g/ml, did not influence the clonogenic potential of PC3 cells, since the survival curves, associated or not with propolis, were found similar, although the combined treatment in CHO-K1 cells exhibited a stimulating proliferative effect. The data

  13. Decoloration Kinetics of Waste Cooking Oil by 60Co γ-ray/H2O2

    Science.gov (United States)

    Xiang, Yulin; Xiang, Yuxiu; Wang, Lipeng

    2016-03-01

    In order to decolorize, waste cooking oil, a dark red close to black solution from homes and restaurants, was subjected to 60Co γ-ray/H2O2 treatment. By virtue of UV/Vis spectrophotometric method, the influence of Gamma irradiation to decoloration kinetics and rate constants of the waste cooking oil in the presence of H2O2 was researched. In addition, the influence of different factors such as H2O2 concentration and irradiation dose on the decoloration rate of waste cooking oil was investigated. Results indicated that the decoloration kinetics of waste cooking oil conformed to the first-order reaction. The decoloration rate increased with the increase of irradiation dose and H2O2 concentration. Saponification analysis and sensory evaluation showed that the sample by 60Co γ-ray/H2O2 treatment presented better saponification performance and sensory score. Furthermore, according to cost estimate, the cost of the 60Co γ-ray/H2O2 was lower and more feasible than the H2O2 alone for decoloration of waste cooking oil.

  14. Different gamma ray ({sup 60} Co) dose effects on Sorghum genotype germination; Efeito de diferentes doses de radiacao gama do {sup 60} Co sobre a germinacao de genotipos de sorgo (Sorghum bicolor)

    Energy Technology Data Exchange (ETDEWEB)

    Tabosa, Jose Nildo; Gomes, Roberto Vicente; Reis, Odemar Vicente dos [Empresa Pernambucana de Pesquisa Agropecuaria (IPA), Recife (Brazil)]. E-mail: tabosa@ipa.br; Colaco, Waldeciro [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Energia Nuclear]. E-mail: wcolaco@ufpe.br

    2004-08-15

    In agriculture, applying irradiation is a very valuable way of obtaining vegetable products for human and animal consumption. Cobalt-60, one of the main sources of gamma-rays, is considered an important tool in plant breeding programs, which have the objective of promoting genetic variability of cultivars with resistance to adverse environments. In this research, the effects of different {sup 60}Co doses on germination vigor and seed germination velocity of forage sorghum genotypes were evaluated. The study was carried out at the IPA (Empresa Pernambucana de Pesquisa Agropecuaria) in Recife, Pernambuco, Brazil. The work was installed in germination boxes, following laboratory recommendations. Thus, a experiment involving three sorghum genotypes (IPA 467-4-2, IPA 02-03-01, and Sudan 4202), five {sup 60}Co doses (Zero, 150, 300, 350, and 400 Gy), was set up. The sees were irradiated before the beginning of the experiment being exposed to gamma rays from a {sup 60}Co-source (cobalt irradiator) at DEN (Nuclear Engineering Department) of the UFPE (Pernambuco Federal University), Brazil. The work also had the objective of evaluating the sorghum genotypes x {sup 60}Co dose interaction. The main results obtained showed that the sorghum genotype IPA 02-03-01 presented the greatest values of germination and vigor percentages, and seed germination velocity, when compared to the others evaluated, on 350 and 400 Gy of {sup 60}Co doses. (author)

  15. 60Coγ射线2.0 Gy剂量诱导大鼠淋巴细胞基因表达的改变%Study of Differential Gene Expression Profiling in Peripheral Blood Lymphocyte of Rat with 2 .0 Gy Gamma Ray Irradiation

    Institute of Scientific and Technical Information of China (English)

    李建国; 尹晶晶; 秦秀军; 张伟; 周晋源; 闻建华

    2013-01-01

    利用Agilent Rat全基因组芯片技术和实时荧光定量PCR技术,采用60 Coγ射线对SD大鼠全身照射,照射剂量为2.0 Gy ,分析照后6、12、24小时大鼠外周血淋巴细胞的差异表达基因谱和通路,同时对基因芯片结果进行验证。结果表明:(1)照后6小时,差异表达基因有1084个,其中上调的736个,下调的348个;照后12小时,差异表达基因有2590个,其中上调的1621个,下调的969个;照后24小时,差异表达基因有3938个,其中上调的2278个,下调的1660个;3个时间点共同差异表达基因有446个,其中上调的274个,下调的172个。(2)照后6小时,差异表达基因涉及到的通路有18个;照后12小时,差异表达基因涉及到的通路有35个;照后24小时,差异表达基因涉及到的通路有38个。其中通路Cell adhesion molecules、Toxoplasmosis、B cell receptor signaling、Intestinal immune network for IgA Production等在照后3个时间点均有出现。(3)差异表达基因Trmt61a和Enc1的相对定量结果与基因芯片检验结果表达趋势一致。%The study analyzed the differential expression profile and pathway of peripheral blood lymphocyte in SD rats 6 ,12 and 24 hours after irradiation to 2 .0 Gy gamma ray .The results showed that at 6 hours after ir-radiation there were 1084 differentially expressed genes of which 736 genes were up-regulated and 348 genes down-regulated .12 hours after irradiation there were 2590 differentially expressed genes of which 1621 genes were up-regulated and 969 genes down-regulated .24 hours after irradiation there were 3938 differentially ex-pressed genes of which 2278 genes were up-regulated and 1660 genes down-regulated .There were 446 co-ex-pressed differential genes at three time points ,of which 274 genes were up-regulated and 172 genes down-regu-lated .The KEGG analysis revealed that 6h point 18 pathways ,12 hours point 35 pathways ,and 24 hours point

  16. A comparison of ionizing radiation damage in CMOS devices from 60Co gamma rays, electrons and protons

    Institute of Scientific and Technical Information of China (English)

    HE Sao-Ping; YAO Zhi-Bin; ZHANG Feng-Qi

    2009-01-01

    Radiation hardened CC4007RH and non-radiation hardened CC4011 devices were irradiated using 80Co gamma rays, 1 MeV electrons and 1--9 MeV protons to compare the ionizing radiation damage of the gamma rays with the charged particles. For all devices examined, with experimental uncertainty, the radiation induced threshold voltage shifts (△Vth) generated by 60Co gamma rays are equal to that of 1 MeV electron and 1-7 MeV proton radiation under 0 gate bias condition. Under 5 V gate bias condition, the distinction of threshold voltage shifts (△Vth) generated by 60Co gamma rays and 1 MeV electrons irradiation are not large, and the radiation damage for protons below 9 MeV is always less than that of 60Co gamma rays. The lower energy the proton has, the less serious the radiation damage becomes.

  17. Evaluation of the Timepix chip radiation hardness using a {sup 60}Co source

    Energy Technology Data Exchange (ETDEWEB)

    Čarná, Mária; Dučevová, Kateřina; Hejtmánek, Martin, E-mail: hejtmark@fzu.cz; Konček, Ondřej; Marčišovský, Michal

    2013-12-21

    Radiation damage is a widely studied topic for its effects on detectors and supporting electronics in various practical applications. Radiation hardness and stability of the detector properties are critical parameters in applications of semiconductor radiation detectors. The 0.25μm CMOS technology used in fabrication of the Medipix2 and Timepix chips provides high degree of inherent radiation hardness. We present the study of operational, detection and signal processing properties of the irradiated Timepix chip exposed to a high-flux {sup 60}Co source reaching the operational limits of the chip. -- Highlights: • Radiation hardness of pixel detector based on Medipix2 against {sup 60}Co has been performed. • The {sup Co} was used as a radiation source due to its usage in number of practical applications. • Systematic study of γ radiation of various energies on the detector systems is desired.

  18. Performance of a Roos ionization chamber in gamma radiation beams ({sup 60}Co)

    Energy Technology Data Exchange (ETDEWEB)

    Perini, Ana P.; Neves, Lucio P.; Caldas, Linda V.E., E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Among the different types of dosimetry instruments, the ionization chambers are the most practical and and important radiation measurement devices due to their high sensitivity and relatively constant response within a wide range of energies. A commercial PTW ionization chamber (Roos electron chamber) usually utilized in X-ray beams, was tested to verify the possibility of its dosimetric application in {sup 60}Co beams. The main tests in this work were: short- and long-term stability, saturation, ion collection efficiency, polarity effect, leakage current and angular dependence. The characterization tests were performed using a Gammatron {sup 60}Co irradiator and a special goniometer made of PMMA. All results were within international recommendations. The reproducibility test presented results within the recommended limit of {+-}1%, and all coefficients of variation observed in the repeatability test were lower than {+-}0.07%. The ion collection efficiency was better than 99.9% for both polarities. For all pairs of polarity evaluated during the saturation test, the polarity effect was lower than the recommended limit. The maximum variation obtained for angular dependence test was only 0.5%. The chamber tested in this work achieved the expected results in the case of all pre-operational tests realized: stability, leakage current, angular dependence, saturation, ion collection and polarity effect. Evaluating the satisfactory results obtained, it is possible to indicate the usefulness of this ionization chamber for dosimetry in {sup 60}Co gamma radiation beams. (author)

  19. Dosimetric evaluation of Radiotherapy units wit {sup 60}Co; Evaluacion dosimetrica de unidades de radioterapia con {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Leon, B. Salinas de; Tovar M, V.; Becerril V, A. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The SSDL network of the IAEA performs, every year, quality audit tests for radiotherapy services ({sup 60} Co units and linear accelerators), and for national SSDL as well. Because of the SSDL-Mexico results in these tests and due to our enthusiasm and confidence in our work, a parallel test has been done , which is described in this talk as well as the results. Nowadays, a second parallel test goes up, which could confirm our optimism and open the possibility to our country to start a national dosimetric audit of {sup 60} Co radiotherapy units. (Author)

  20. Doses in sensitive organs during prostate treatment with a 60Co unit.

    Science.gov (United States)

    Vega-Carrillo, H R; Navarro Becerra, J A; Pérez Arrieta, M L; Pérez-Landeros, L H

    2014-01-01

    Using thermoluminiscent dosimeters the absorbed dose in the bladder, rectum and thyroid have been evaluated when 200 cGy was applied to the prostate. The treatment was applied with a (60)Co unit. A water phantom was built and thermoluminiscent dosimeters were located in the position where the prostate, bladder, rectum and thyroid are located. The therapeutic beam was applied in 4 irradiations at 0, 90, 180 and 270° with the prostate at the isocenter. The TLDs readouts were used to evaluate the absorbed dose in each organ. The absorbed doses were used to estimate the effective doses and the probability of developing secondary malignacies in thyroid, rectum and bladder.

  1. Comparison of treatment in soybean grains between {sup 60}Co and e-beans applications

    Energy Technology Data Exchange (ETDEWEB)

    Fanaro, Gustavo B.; Araujo, Michel M.; Thomaz, Fernanda S.; Duarte, Renato C.; Villavicencio, Anna Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: gbfanaro@ipen.br; villavic@ipen.br

    2007-07-01

    Soybean is the most important oleaginous cultivated in Brazil, who is the second largest exported in the world, and generates high incomes, direct and indirectly, its oils could be used since to cook even to machine's fuel and the nutrients become basic for the feeding human being, beyond its by-products, that offer great diversities of products for the nourishing industry. Between the main factors that limit the attainment of high incomes, are the illnesses caused by microorganism like fungi, bacteria, and viruses that, in general, are difficult to control and cause damages on harvest of billions of dollar every year. An alternative to minimize the losses is preserving the grains through the irradiation that can come today from two different main sources: e-beam and {sup 60}Co. Beyond power to be off when it will not be in use, the source of e-beams machines does not need to be recharged, is easily available, possess high tax of dose and low energy. However the {sup 60}Co have low dose rate, high energy and the photons emission is continuous. This work aims to compare the effects of the radiation through viscosimetry, DNA Comet Assay and Cooking time techniques in soybean grains at doses 0, 1.0, 3.0 and 5.0kGy irradiated in ambient temperature at {sup 60}Co source Gammacell 220 (A.E.C. Ltda) and in e-beam accelerator - Radiation Dynamics (Radiation Dynamics Co. model JOB, New York, USA), 1.5 MeV- 25mA with the lower dose. (author)

  2. Sensitivity to. gamma. rays of avian sarcoma and murine leukemia viruses. [/sup 60/Co, uv

    Energy Technology Data Exchange (ETDEWEB)

    Toyoshima, K. (Osaka Univ., Japan); Niwa, O.; Yutsudo, M.; Sugiyama, H.; Tahara, S.; Sugahara, T.

    1980-09-01

    The direct inactivation of avian and murine oncoviruses by ..gamma.. rays was examined using /sup 60/Co as a ..gamma..-ray source. The inactivation of murine leukemia virus (M-MuLV) followed single-hit kinetics while the subgroup D Schmidt-Ruppin strain of avian sarcoma virus (SR-RSV D) showed multihit inactivation kinetics with an extrapolation number of 5. The two viruses showed similar uv-inactivation kinetics. The genomic RNA of the SR-RSV D strain was degraded by ..gamma.. irradiation faster than its infectivity, but viral clones isolated from the foci formed after ..gamma.. irradiation had a complete genome. These results suggest that SR-RSV D has a strong repair function, possibly connected with reverse transcriptase activity.

  3. The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma Gondii Tachyzoites

    Directory of Open Access Journals (Sweden)

    YB Zeng

    2013-03-01

    Full Text Available Background: Toxoplasmosis is one of the most common parasitic infections of humans and other mammals. This study was aimed to understand the mechanism of action of veterinary medicine-sulfachlo­ropyrazine (SPZ, 99.97% against Toxoplasma gondii.Methods: T. gondii tachyzoites were soaked in PBS (as a control or SPZ (250 mg/mL for 2 h at 37 °C. After being processed, any ultrastructural changes of the tachyzoites that had occurred were observed by Scanning Electron Microscopy (SEM and Transmission Electron Microscopy (TEM.Results: The tachyzoites from control groups with a uniform size had a smooth surface and intact cell or nuclear membranes. In addition, an oval-shaped nucleus, conoids and micronemes were also observed. By contrast, many parasites from the SPZ-treated groups were detrimentally affected by the treatment. Some appeared to be of the vacuolization in their cytoplasm, with the substantial reduc­tion in the number of dense granules and the blur of some organelles.Conclusion: The morphology and ultrastructure of tachyzoites can be affected significantly by SPZ, which might kill the parasite by inhibiting its energy metabolism, inducing apoptosis and damaging its structure. The study provides an experimental basis for further study on the mechanism of SPZ against T. gondii.

  4. Susceptibility of various cell lines to Neospora caninum tachyzoites cultivation

    Directory of Open Access Journals (Sweden)

    Khordadmehr, M.,

    2014-05-01

    Full Text Available Neospora caninum is a coccidian protozoan parasite which is a major cause of bovine abortions and neonatal mortality in cattle, sheep, goat and horse. Occasionally, cultured cells are used for isolation and multiplication of the agent in vitro with several purposes. In this study the tachyzoite yields of N. caninum were compared in various cell cultures as the host cell lines. Among the cell cultures tested, two presented good susceptibility to the agent: cell lines Vero and MA-104. SW742 and TLI (in vitro suspension culture of lymphoid cells infected with Theileria lestoquardi showed moderate sensitivity. No viable tachyzoite were detected in the culture of MDCK and McCoy cell lines. These results demonstrate that MA-104 and SW742 cells present adequate susceptibility to N. caninum compared to Vero cells, which have been largely used to multiply the parasite in vitro. Moreover, these have easy manipulation, fast multiplication and relatively low nutritional requirements. In addition, the result of this study showed that TLI cell line as a suspension cell culture is susceptible to Nc-1 tachyzoites infection and could be used as an alternative host cell line for tachyzoites culture in vitro studies.

  5. Effect of {sup 60}Co radiation processing in mate (Ilex paraguariensis); Efeito do processamento por radiacao de {sup 60}Co na erva-mate (llex paraguariensis)

    Energy Technology Data Exchange (ETDEWEB)

    Furgeri, Camilo

    2009-07-01

    The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from {sup 60}Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative

  6. Determination of {sup 60}Co sorption in natural clinoptilolite; Determinacion de la sorcion de {sup 60}Co en clinoptilolita natural

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez B, E.; Granados C, F. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    It was studied the clinoptilolite behavior coming from a deposit in Taxco, Guerrero in hydration and stabilization conditions with sodium for determining its sorption properties. The ion exchange process was carried out through gamma spectrometry using a CoCl{sub 2} solution marked with {sup 60} Co at p H 6.5 in different contact times. It was observed a maximum sorption of 0.408 m eq Co{sup +2}/g mineral, from 0.314 m eq Co{sup +2}/g mineral correspond at ion exchange. (Author)

  7. Microbiological analysis of peach palm in natura submitted to {sup 60}Co radiation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Priscila V.; Araujo, Michel M.; Nunes, Thaise C.F.; Costa, Helbert S.F.; Villavicencio, Anna Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)], e-mail: priscilavsilva@gmail.com, e-mail: villavic@ipen.br; Hojeije, Khalil Y. [Floresta Industria e Comercio Ltda., Sao Paulo, SP (Brazil)

    2009-07-01

    The palm tree (Bactris gasipaes Kunth) is a species with high potential benefits, because of the nutritional value of its fruits that could be used both in human and animals feeding and mainly for peach palm extraction. It represents a great source of dietary fiber and a moderate source of magnesium and iron. Food irradiation is a worldwide technology that aims to improve the product quality, in order to eliminate diverse microorganisms that can spoil the food. Radiation processing, in the recommended doses, causes very few chemical alterations and nutritional losses in foods, being considered insignificant and/or similar to other food treatments. The objective of this study was to evaluate the effect of irradiation on microbiological counts of mesophilic aerobic in the peach palm in natura. Samples were irradiated with 1.0 and 1.5 kGy using a {sup 60}Co multipurpose irradiator. Radiation treatment appeared to be a useful alternative to reduce microbial contamination in the samples analyzed. (author)

  8. Dose assessment for ingestion of a 330 kilo-becquerel {sup 60}Co hot particle

    Energy Technology Data Exchange (ETDEWEB)

    Whillans, D.W.; Chase, W.J.; Wolodarsky, W.H. [Health Physics Department, Ontario Power Generation, Whitby, Ontario, L1 N 9E3 (Canada)

    2007-07-01

    On leaving the irradiated fuel bay at Pickering A nuclear power station, a worker triggered a whole body monitor alarm with activity in or on his head, and despite careful decontamination techniques he subsequently swallowed a hot particle. Over the next 3 d, the radioactivity was tracked through the body. It was then excreted in a single faecal sample and recovered for physical and radiochemical analysis. This analysis demonstrated that the particle contained 330 kBq of {sup 60}Co and only traces of other radioactivity. Its dimensions were {approx}50-130 {mu}m and its composition was consistent with that of Stellite 6. A dose assessment was carried out taking into account the residence time of the particle in the mouth and its transit through the body. The estimated committed effective dose was 1.4 mSv, and the equivalent dose to the maximally exposed 1 cm{sup 2} of skin, 81 mSv. (authors)

  9. 60Co gamma radiation effect on AlGaN/AlN/GaN HEMT devices

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-Ping; LUO Yin-Hong; WANG Wei; ZHANG Ke-Ying; GUO Hong-Xia; GUO Xiao-Qiang; WANG Yuan-Ming

    2013-01-01

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established.The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically,and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out.The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated,and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained.

  10. Study of {sup 60}Co as gamma source in backscatter gamma densitometers

    Energy Technology Data Exchange (ETDEWEB)

    Gholipour Peyvandi, R.; Taheri, A.; Rahmanzadeh Tootkaleh, S.; Askari Lehdarboni, M. [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Islami Rad, S.Z. [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Univ. of Qom (Iran, Islamic Republic of). Dept. of Physic

    2015-07-15

    In this work the performance of backscatter gamma densitometer is studied using {sup 60}Co as gamma source. The ability of the densitometer to determine the liquid's interfaces in multi-phase flows was assessed. The aim mainly was to investigate the possibility of using {sup 60}Co in this system. Furthermore, a comparison between {sup 60}Co and was done. The obtained results indicate that {sup 60}Co can be advantageous in this regard.

  11. [In vitro co-cultivation of Toxoplasma gondii tachyzoites with rat brain astrocytes].

    Science.gov (United States)

    Li, Dong-na; Liang, You-sheng; Zhou, Yong-hua; Zhang, Huan-xiang; Sheng, Hai-ying; Luo, Wei; Gong, Wei; Zhuge, Hong-xiang

    2010-08-01

    Purified astrocytes were cultured in plates. When astrocytes grew over 80% of the plate, tachyzoites of Toxoplasma gondii RH strain were added for co-culture. In the period of 0-72 h, change of the astrocytes and tachyzoites was observed after Giemsa staining. In 0-48 h, monodansylcadaverine (MDC) was used to study the action of autophagy in the process of tachyzoites invading astrocytes. At 1 h co-culture, tachyzoites had entered in astrocytes and the autophagosomes appeared. At 4 h, the autophagosomes increased pronouncedly. However, after 12 h, number of autophagosomes considerably decreased and damage of the cells occurred. 48 h later, autophagosomes disappeared and more astrocytes were destroyed. At 72 h most cells destroyed and tachyzoites were released. The result showed that autophagy is inhibited when the astrocytes were in vitro infected by tachyzoites.

  12. Studying the Effect of Ionization Radiation of 60Co on the Spirulina

    Science.gov (United States)

    Ai, Weidang; Guo, Shuang-Sheng; Ai, Weidang; Dong, Wen-Ping; Qin, Li-Feng; Tang, Yong-Kang

    It studied the effect of ionization radiation on the Spirulina plastensis(No.6) by using the γ-rays of 60 Co. In the experiment, Spirulina were irradiated, and the dose of the ionization radiation covered 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0kGy. After irradiating, these Spirulina were cultured under the same conditions. During the course of the experiment, the growth rate, photosynthetic efficiency and nutrition quality of the Spirulina, were analyzed. From the results, low dose of γ-rays (less than 1.5kGy) could improve the content of phycobilin and protein of Spirulina. Only small changes in the morphology of algae filament were found at dose less than 1.0kGy. But with the increase of the dose of γ-rays (more than 1.5kGy), the filaments would break up or even disintegrate. Spirulina had stronger ionization radiation proof and self-rehabilitation capacity, but the growth of Spirulina was stagnated. The LD50 (i.e. the dose resulted in 50% death of the Spirulina) of the colony was 2.0kGy. Considering the capacity of being resistant to γ-rays irradiation, Spirulina can be considered as one of the key biological components in the Controlled Ecological Life Support System (CELSS) for future long-term space missions. Keywords: Controlled Ecological Life Support System (CELSS); Spirulina; ionization radiation; biological component

  13. Succinylcholine-induced hyperkalemia in the rat following radiation injury to muscle. [60Co

    Energy Technology Data Exchange (ETDEWEB)

    Cairoli, V.J.; Ivankovich, A.D.; Vucicevic, D.; Patel, K.

    1982-02-01

    During anesthetic preparation of a patient who had received routine radiation therapy of sarcoma of the leg, cardiac collapse occurred following succinylcholine (SCh) administration. Experiments were designed to test the hypothesis that radiation injury to muscle might cause increased sensitivity to SCh similar to that reported in patients with muscle trauma, severe burns, and lesions causing muscle denervation. Venous plasma potassium levels and arterial blood gas tensions were measured in rats after they were given SCh (3 mg/kg) at various times following 60Co irradiation of the hind legs. Nonirradiated rats responded to SCh with a slight but statistically significant increase in plasma K+. Rats subjected to high levels of radiation (10,000 to 20,000 R) and given SCh 4 to 7 days later responded in the same way as the control rats. Plasma K+ levels in rats exposed to a fractionated irradiated dosage (25000 R given twice with a 1-week interval) followed by SCh 1 week later were similar to those in the control group, but when SCh was given 2 weeks later (3 weeks after initial irradiation) there was a marked elevation of plasma K+, from 3.6 to 7.7 meq/L, a statistically significant increase.

  14. Toxoplasma gondii: a rapid method for the isolation of pure tachyzoites: preliminary characterization of its genome

    Directory of Open Access Journals (Sweden)

    Juan Carlos Garberi

    1990-12-01

    Full Text Available A rapid and simple technique for the purification of Toxoplasma gondii tachyzoites was developed. Highly purified parasites were obtained from the peritoneal exudates of infected mice by means of two consecutive discontinous sucrose gradients run at low speed (10,000xg, 30 min. Parasites obtained by this method conserved its biological activity. Hybridizations tudies with DNA from healthy mice and from purified tachyzoites preparations demonstrated that Toxoplasma gondii tachyzoites DNA could be obtained with better than 90 per cents purity. Preliminary studies with DNA endonucleases showed the presence in the tachyzoites genome of highly repetitives sequences.

  15. The combined effect of 1,25(OH)2D3 with 60Co γ-rays irradiation on ovarian cancer cell SKOV-3%1,25(OH)2D3和γ射线对人卵巢癌细胞SKOV-3的联合作用

    Institute of Scientific and Technical Information of China (English)

    胡志勇; 李冰燕; 冯晓青; 丁晓飞; 童建; 张增利

    2011-01-01

    为探讨活性维生素D(1,25-dihydroxyvitamin D3,1,25(OH)2D3)与γ射线联合应用对SKOV-3细胞增殖的影响,评价1,25(OH)2D3能否增强γ射线对SKOV-3细胞的抑制作用,将实验分为1,25(OH)2D3组,60Coγ射线组以及两者联合作用组和对照组,用MTT法测定细胞抑制率,并用流式细胞仪进行细胞周期、细胞内活性氧(ROS)和钙离子[Ca2+]i分析.结果发现:1,25(OH)2D3与γ射线单独应用可以抑制SKOV-3细胞的增殖,并且1,25(OH)2D3能显著增强γ射线对细胞的抑制作用;细胞周期分析显示,1,25(OH)2D3增加了SKOV-3细胞Go/G1期的比例,γ射线组增加了G2/M期的细胞比例,而联合作用组中G2/M期的比例明显增加,使细胞进一步阻滞于G2/M期;并且1,25(OH)2D3组和γ射线单独应用组均能增加细胞内ROS及[Ca2+i]浓度,并且联合作用组增加幅度最大(P<0.05).结果提示,1,25(OH)2D3可以增强γ射线对卵巢癌细胞株SKOV-3抑制作用.

  16. ONE CASE OF LEUKEMIA INDUCED BY 60Co ACCIDENT

    Institute of Scientific and Technical Information of China (English)

    邵松生; 冯嘉林; 等

    1995-01-01

    The peripheral blood lymphocyte chromosomes in a case of 60Co γ rays accident were examined at 2.5h after exposure.The frequency of the dicentrics plus centric rings was 89% and exposure dose was estimated to be 4.78 (4.53-4.88)GY.The examinations of lymphocyte chromosome aberration within follow-up 12a showed that the incidence of Dic+R reduced with lg regrssion(r=-0.9895).While the number of ceels with stable aberration remained unchanged and showed a tendency to increase.During the period of leukemia,bone marrow cell chromosome aberrations were studied by method of G-banding.Of 13 cells observed,4 cells belonged to normal karyotypes.Among 9 aberration cells,12 aberrations were detected.The majority of which were classified as translocation,deletion and inversion,Numeric aberrations were-9,12,20-,22,-y.This case suggested that acute lymphocytic leukemia was induced after radiation accident.

  17. Use of {sup 60}Co panoramic source in the induction of oral mucositis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Maira F.; Benetti, Carolina; Zezell, Denise M., E-mail: mairandrade@yahoo.com, E-mail: zezell@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Correa, Luciana, E-mail: lcorrea@usp.br [Universidade de Sao Paulo (FO/USP), Sao Paulo, SP (Brazil). Fac. de Odontologia

    2013-07-01

    Oral Mucositis is a well-known side effect of chemo-radiotherapy in cancer patients or transplant recipients that could induce hospitalization or impairs therapy in different levels of severity. This study is devoted to define the first steps in the research of low level laser treatments in oral mucositis, proposing a {sup 60}Co radiation to experimentally induce oral mucositis in rats using Panoramic gamma irradiator, simulating usual radiotherapy of head and neck cancer. Fifteen male Wistar rats, above 250g, were irradiated at Centro de Tecnologia das Radiacoes (IPEN - CNEN/SP) and divided in three experimental groups, with different single doses of radiation (30 Gy, 25 Gy and 20 Gy). The animals were observed for a 20 days period. Animals that received 30 Gy and 25 Gy developed greater severity of mucositis and premature euthanasia was performed in these groups on the 7th and 11th day after the irradiation, respectively. The 20 Gy group developed oral mucositis grading from moderated to severe between the days 7 and 11 after irradiation, with progressive body mass loss and decrease in the intake of food and water. These animals recovered from oral mucositis around the 18th day and clinical remission at the 20th day. The single dose of 20 Gy Gamma radiation proved to be efficient way for inducing oral mucositis in rats, allowing the establishment of an experimental model for oral mucositis in rats for future use on interventions of this serious aspect of radiation therapy, such as laser therapy using different wave lengths and power densities. (author)

  18. A standard Fricke dosimeter compared to an ionization chamber used for dosimetric characterization of 60Co photon beam

    Science.gov (United States)

    Moussous, Ouiza; Medjadj, Toufik

    2016-06-01

    The main objective of this study was to investigate the Fricke dosimeter water equivalent system for measurement of dosimetric parameters for photon beam. The parameters measured with the Fricke dosimeter were compared to those obtained with an ionization chamber. In this work characteristics for 60Co γ-rays of field sizes ranging from 5 × 5 cm2 to 20 × 20 cm2 are reported. The measurements were carried out in the secondary standard dosimetry laboratory using a collimated 60Co gamma source therapy unit. The 60Co beam output in terms of absorbed dose to water was obtained as per IAEA TRS 398 recommendations using cylindrical ionization chamber, whose ND,w has been supplied by the IAEA's reference laboratory. Specific quantities measured include: output factors, peak scatter factor, lateral beam profiles and percentage depth dose. The Fricke dosimeters were irradiated in a water phantom using the suitable poly (methyl methacrylate), PMMA stand. Our results demonstrate that Fricke dosimeter and ionization chamber agree with each other.

  19. Determination of late-time Gamma-Ray (60Co) sensitivity of single diffusion Lot 2N2222A transistors.

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, Kendall Russell; Kajder, Karen C.; Peters, Curtis D. (American Staff Augmentation Providers, LLC, Albuquerque, NM)

    2008-08-01

    Sandia National Laboratories (SNL) has embarked on a program to develop a methodology to use damage relations techniques (alternative experimental facilities, modeling, and simulation) to understand the time-dependent effects in transistors (and integrated circuits) caused by neutron irradiations in the Sandia Pulse Reactor-III (SPR-III) facility. The development of these damage equivalence techniques is necessary since SPR-III was shutdown in late 2006. As part of this effort, the late time {gamma}-ray sensitivity of a single diffusion lot of 2N2222A transistors has been characterized using one of the {sup 60}Co irradiation cells at the SNL Gamma Irradiation Facility (GIF). This report summarizes the results of the experiments performed at the GIF.

  20. Determination of the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters for {sup 125}I and {sup 103}Pd brachytherapy sources relative to {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Reed, J. L., E-mail: jlreed2@wisc.edu; Micka, J. A.; Culberson, W. S.; DeWerd, L. A. [Department of Medical Physics, University of Wisconsin–Madison, Madison, Wisconsin 53705 (United States); Rasmussen, B. E. [Department of Radiation Oncology, UP Health System Marquette, 580 West College Avenue, Marquette, Michigan 49855 (United States); Davis, S. D. [Department of Medical Physics, McGill University Health Centre, Montreal General Hospital (L5-112), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada)

    2014-12-15

    Purpose: To determine the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters (TLD-100) for {sup 125}I and {sup 103}Pd brachytherapy sources relative to {sup 60}Co. Methods: LiF:Mg,Ti TLDs were irradiated with low-energy brachytherapy sources and with a {sup 60}Co teletherapy source. The brachytherapy sources measured were the Best 2301 {sup 125}I seed, the OncoSeed 6711 {sup 125}I seed, and the Best 2335 {sup 103}Pd seed. The TLD light output per measured air-kerma strength was determined for the brachytherapy source irradiations, and the TLD light output per air kerma was determined for the {sup 60}Co irradiations. Monte Carlo (MC) simulations were used to calculate the dose-to-TLD rate per air-kerma strength for the brachytherapy source irradiations and the dose to TLD per air kerma for the {sup 60}Co irradiations. The measured and MC-calculated results for all irradiations were used to determine the TLD intrinsic energy dependence for {sup 125}I and {sup 103}Pd relative to {sup 60}Co. Results: The relative TLD intrinsic energy dependences (relative to {sup 60}Co) and associated uncertainties (k = 1) were determined to be 0.883 ± 1.3%, 0.870 ± 1.4%, and 0.871 ± 1.5% for the Best 2301 seed, OncoSeed 6711 seed, and Best 2335 seed, respectively. Conclusions: The intrinsic energy dependence of TLD-100 is dependent on photon energy, exhibiting changes of 13%–15% for {sup 125}I and {sup 103}Pd sources relative to {sup 60}Co. TLD measurements of absolute dose around {sup 125}I and {sup 103}Pd brachytherapy sources should explicitly account for the relative TLD intrinsic energy dependence in order to improve dosimetric accuracy.

  1. Bioremediation of {sup 60}Co from simulated spent decontamination solutions

    Energy Technology Data Exchange (ETDEWEB)

    Rashmi, K.; Naga Sowjanya, T.; Maruthi Mohan, P.; Balaji, V.; Venkateswaran, G

    2004-07-26

    Bioremediation of {sup 60}Co from simulated spent decontamination solutions by utilizing different biomass of (Neurospora crassa, Trichoderma viridae, Mucor recemosus, Rhizopus chinensis, Penicillium citrinum, Aspergillus niger and, Aspergillus flavus) fungi is reported. Various fungal species were screened to evaluate their potential for removing cobalt from very low concentrations (0.03-0.16 {mu}M) in presence of a high background of iron (9.33 mM) and nickel (0.93 mM) complexed with EDTA (10.3 mM). The different fungal isolates employed in this study showed a pickup of cobalt in the range 8-500 ng/g of dry biomass. The [Fe]/[Co] and [Ni]/[Co] ratios in the solutions before and after exposure to the fungi were also determined. At micromolar level the cobalt pickup by many fungi especially the mutants of N. crassa is seen to be proportional to the initial cobalt concentration taken in the solution. However, R. chinensis exhibits a low but iron concentration dependent cobalt pickup. Prior saturating the fungi with excess of iron during their growth showed the presence of selective cobalt pickup sites. The existence of cobalt specific sorption sites is shown by a model experiment with R. chinensis wherein at a constant cobalt concentration (0.034 {mu}M) and varying iron concentrations so as to yield [Fe/Co]{sub initial} ratios in solution of 10, 100, 1000 and 287 000 have all yielded a definite Co pickup capacity in the range 8-47 ng/g. The presence of Cr(III)EDTA (3 mM) in solution along with complexed Fe and Ni has not influenced the cobalt removal. The significant feature of this study is that even when cobalt is present in trace level (sub-micromolar) in a matrix of high concentration (millimolar levels) of iron, nickel and chromium, a situation typically encountered in spent decontamination solutions arising from stainless steel based primary systems of nuclear reactors, a number of fungi studied in this work showed a good sensitivity for cobalt pickup.

  2. Effect of gamma radiation of {sup 60}Co in the variability of chinese bean [Vigna unguiculata (l.) Walpers] en R{sub 4}M{sub 4}; Efecto de la radiacion gamma de {sup 60}Co en la variabilidad de frijol chino [Vigna unguiculata (l.) Walpers] en R{sub 4}M{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Salmeron E, J.; Bueno J, J.E.; Valencia E, F. [CSAEGro, Iguala, Guerrero, Tel and Fax 01 733 (33) 24328 (Mexico); Cervantes S, T. [IREGEP (Mexico); Cruz T, E. De la [ININ, Departamento de Biologia, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: csaegro@prodigy.net.mx

    2007-07-01

    Selection of plants of Chinese bean coming from seed irradiated with gammas of {sup 60}Co in the generation R{sub 4}M{sub 4} (fourth recurrent irradiation, fourth segregate generation) were carried out, taking as selection approaches the plant architecture, the numbers of sheaths for plant, sheath longitude, position of the sheaths, grain size and resistance to plagues and illnesses. 17 lines were selected for grain and 3 lines with fodder characteristics of black grain color were also obtained. (Author)

  3. Toxoplasma gondii aspartic protease 1 is not essential in tachyzoites.

    Science.gov (United States)

    Polonais, Valerie; Shea, Michael; Soldati-Favre, Dominique

    2011-08-01

    Aspartic proteases are important virulence factors for pathogens and are recognized as attractive drug targets. Seven aspartic proteases (ASPs) have been identified in Toxoplasma gondii genome. Bioinformatics and phylogenetic analyses regroup them into five monophyletic groups. Among them, TgASP1, a coccidian specific aspartic protease related to the food vacuole plasmepsins, is associated with the secretory pathway in non-dividing cells and relocalizes in close proximity to the nascent inner membrane complex (IMC) of daughter cells during replication. Despite a potential role for TgASP1 in IMC formation, the generation of a conventional knockout of the TgASP1 gene revealed that this protease is not required for T. gondii tachyzoite survival or for proper IMC biogenesis.

  4. Radiolysis of D(+)-carnitine by /sup 60/Co-. gamma. -radiation and formation of L(+)-. beta. -methylcholine

    Energy Technology Data Exchange (ETDEWEB)

    Loester, Heinz; Strack, Erich; Seim, Hermann

    1986-06-01

    The radiolysis of D(+)-carnitine by /sup 60/Co-..gamma..-radiation was examined to obtain optically active ..beta..-methylcholine. It was found that the radiolysis leads to a number of trimethylammonium bases but to no other betaines. (+)-..beta..-Methylcholine and acetonyltrimethylammonium could be identified by means of common analytical methods. The amounts of methylamines formed by irradiation were very small. Racemization of the D(+)-carnitine did not occur during irradiation, L(-)-carnitine was not found when an enzymatical determination method was used. The fact that (+)-..beta..-methylcholine was formed from D(+)-carnitine is pharmacologically important, because acetyl-L(+)-..beta..-methylcholine has a strong interaction with muscarinic receptors.

  5. Cloning of cDNA Encoding GRA1 Protein of Tachyzoite Toxoplasma Gondii Local Isolate

    Directory of Open Access Journals (Sweden)

    Erma Sulistyaningsih

    2015-10-01

    Full Text Available Gene encoding GRA1 protein is potent DNA-vaccine candidate against toxoplasmosis. The aim of the researchwas to clone the gene encoding GRA1 protein of tachyzoite Toxoplasma gondii local isolate by DNA recombinanttechnology. Tachyzoite was grown in Balb/c mice in vivo. Messenger RNA was isolated from total RNA and itwas used to synthesis cDNA. Complementary DNA encoding GRA1 protein of tachyzoite Toxoplasma gondii localisolate was amplified and cloned in a prokaryote cloning vector. The recombinant GRA1-encoding gene was thendigesting using EcoRI restriction endonuclease and sequencing. The result showed that the recombinant GRA1-encoding gene consisted of DNA sequences encoding all signal peptide and mature peptide of GRA1 protein.Alignment of recombinant GRA1 sequence to gene encoding GRA1 protein of Toxoplasma gondii RH isolate showed100% homologous.Keywords: GRA1 protein, Toxoplasma gondii, tachyzoite, cloning, cDNA

  6. Toxoplasma gondii: demonstration of intrinsic peroxidase activity during lacto-peroxidase mediated radioiodination of tachyzoites

    Energy Technology Data Exchange (ETDEWEB)

    Gallois, Y.; Tricaud, A.; Foussard, F.; Hodbert, J.; Girault, A.; Mauras, G.; Dubremetz, J.F.

    1986-01-01

    Tachyzoites of Toxoplasma gondii have been radioiodinated under various conditions with or without lactoperoxidase, with glucose oxidase being used to generate hydrogen peroxide. Erythrocytes were iodinated simultaneously as a control. In our conditions, tachyzoites were more intensely labelled in the absence of lactoperoxidase. This result can be explained by the existence of an intrinsic peroxidase activity which interfere with the exogenously added enzyme during surface radioiodination.

  7. Development and evaluation of a technique for in vivo monitoring of 60Co in human lungs

    Science.gov (United States)

    de Mello, J. Q.; Lucena, E. A.; Dantas, A. L. A.; Dantas, B. M.

    2016-07-01

    60Co is a fission product of 235U and represents a risk of internal exposure of workers in nuclear power plants, especially those involved in the maintenance of potentially contaminated parts and equipment. The control of 60Co intake by inhalation can be performed through in vivo monitoring. This work describes the evaluation of a technique through the minimum detectable activity and the corresponding minimum detectable effective doses, based on biokinetic and dosimetric models of 60Co in the human body. The results allow to state that the technique is suitable either for monitoring of occupational exposures or evaluation of accidental intake.

  8. Comparative effects of 60Co gamma-rays and neon and helium ions on cycle duration and division probability of EMT 6 cells. A time-lapse cinematography study.

    Science.gov (United States)

    Collyn-d'Hooghe, M; Hemon, D; Gilet, R; Curtis, S B; Valleron, A J; Malaise, E P

    1981-03-01

    Exponentially growing cultures of EMT 6 cells were irradiated in vitro with neon ions, helium ions or 60Co gamma-rays. Time-lapse cinematography allowed the determination, for individual cells, of cycle duration, success of the mitotic division and the age of the cell at the moment of irradiation. Irradiation induced a significant mitotic delay increasing proportionally with the delivered dose. Using mitotic delay as an endpoint, the r.b.e. for neon ions with respect to 60Co gamma-rays was 3.3 +/- 0.2 while for helium ions it was 1.2 +/- 0.1. Mitotic delay was greatest in those cells that had progressed furthest in their cycle at the time of irradiation. No significant mitotic delay was observed in the post-irradiation generation. Division probability was significantly reduced by irradiation both in the irradiated and in the post-irradiated generation. The reduction in division probability obtained with 3 Gy of neon ions was similar to that obtained after irradiation with 6 Gy of helium ions or 60Co gamma-rays.

  9. The Application of Fucus vesiculosus as a Bioindicator of 60Co Concentrations in the Danish Straits

    DEFF Research Database (Denmark)

    Boelskifte, S.

    1985-01-01

    The occurrence of 60Co in the Danish Straits is investigated by applying the seaweed Fucus vesiculosus as a bioindicator. In order to describe different dispersion situations, three areas have been studied separately: the North Sea, where it is possible to measure 60Co from sources in France and...... of distance from Barsebäck. Problems of uncertainty related to differences in environmental parameters are discussed and new investigations to improve the use of Fucus as a bioindicator are suggested....

  10. In vitro response of the human breast cancer cell line MDAMB-231 and human peripheral blood mononuclear cells exposed to {sup 60}Co at single fraction

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Lidia Maria; Campos, Tarcisio Passos Ribeiro de [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear]. E-mail: lidia.andrade@unifenas.br; Leite, M.F. [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Fisiologia e Biofisica; Goes, A.M. [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Bioquimica e Imunologia

    2005-10-15

    Radiotherapy using gamma rays is a common modality of breast cancer treatment. The aim of this research is to investigate the biological response of the human breast cancer cell line MDAMB-231 and human peripheral blood mononuclear cells (PBMC) exposed in vitro to {sup 60} Co irradiation at a single fraction of 10 Gy, 25 Gy and 50 Gy doses at 136,4 cGy.min{sup -1} rate. Cells were irradiated at room temperature by the Theratron 80 radiotherapy system. Biological response was evaluated through cellular viability using MTT assay and nucleus damages visualized by Propidium Iodide assay and electrophoresis agarose gel after gamma irradiation. Nucleus damages induced by {sup 60} Co irradiation were compared to damage caused by cell exposure to 10% methanol. The 50 Gy dose of irradiation did not stimulate nucleus damages at the same level as that affected by 10% methanol induction in the MDAMB-231. Further studies are necessary to understand these mechanisms in the MDAMB-231 human breast carcinoma cell line.(author)

  11. The effects of 60Co γ-ray on poly(ethylene-co-vinyl acetate)/carbon black composites

    Science.gov (United States)

    Lee, Kyoung-Yong; Kim, Ki-Yup

    2008-04-01

    Cables used in a nuclear power plant are irradiation suppressing ones. Until now, researches on the irradiation suppressing cables have mainly been focused on insulation materials. Therefore, in this paper, the non-isothermal crystallization behaviors and degradation characteristics of ethylene vinyl acetate-carbon black (EVA-CB), used as a shielding material, were investigated by means of the Differential scanning calorimetry (DSC) and chemiluminescence analyzer (CL). The specimens were cooled after removing thermal history at 150 °C for 5 min by changing the cooling rates to 5, 7.5, 10, 15 and 20 °C/min with DSC. In addition, after maintaining a thermal equilibrium at each temperature of 25, 50, 75, 100, 125, 150 and 175 °C, their thermoluminescence was measured for 20 min with CL equipment. The 60Co γ-ray was used for irradiation. Tc, T0, T∞ and t1/2 in the DSC experiments are found to decrease gradually as radiation dose increases. Secondly, with the CL experiment, the 0.1, 0.25 and 0.5 MGy EVA-CB composites were found to show a much smaller thermoluminescence than the intact EVA-CB composites, while the 0.75 and 1 MGy EVA-CB composites were found to show a much higher thermoluminescence than ones.

  12. Study of recombination processes for 'electron-hole' pairs in germanium irradiated by {gamma} rays from {sup 60}Co using the photovoltaic effect in P-N junctions; Etude du processus de recombinaison des paires ''electron-trou'' dans le germanium irradie par les rayons {gamma} du cobalt 60 a l'aide de l'effet photovoltaique dans les jonctions P-N

    Energy Technology Data Exchange (ETDEWEB)

    Zahedi-Mochadam, A.A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-10-01

    Using the photo-voltaic effect in p-n junctions, we have studied, during bombardment, the mechanism of the recombination of 'electron-hole' pairs in the presence of structure defects produced in germanium of the N and P types by {gamma} rays from a Co{sup 60} source. At 310 K the level of the recombination centres is situated 0.25 eV above the conduction band and the capture cross-sections of the holes and of the electrons have the respective values of: {sigma}{sub p} = 4 X 10{sup -15} cm{sup 2} and {sigma}{sub n} = 3 X 10{sup -15} cm{sup 2}. The value of {sigma}{sub n} appears to be under-estimated because the number of defects in P-type samples appears to be lower than that in N-type samples. These results lead to the conclusion that the interstitials are responsible for the recombination. At 80 K it has been found that in N-type samples, a shallow level exists at O.05 eV below the conduction band with a capture cross-section for the holes of {sigma}{sub p} {>=} 10{sup -14} cm{sup 2}. We believe that in this case the recombination of charge carriers is controlled by the neighbouring 'defect-interstitial' pairs. In P-type samples at low temperature, the life-time is practically constant during irradiation. This fact is attributed to a spontaneous annealing of defects ol purely electrical origin. In the last part of the work the study of the photo-voltaic effect applied to the problem of gamma radiation dosimetry is considered. It is shown that such dosimeters, based on this principle, make it possible to measure the intensity of gamma rays over a very wide range. (author) [French] En utilisant l'effet photovoltaique dans les jonctions p-n, nous avons etudie au cours du bombardement le mecanisme de recombinaison des paires 'electron-trou' en presence des defauts de structure introduits dans le germanium de type N et de type P par les rayons gamma d'une source de Co{sup 60}. A 310 K, le niveau des centres de recombinaison se

  13. Aminothiol Receptors for Decorporation of Intravenously Administered 60Co in the Rat

    Energy Technology Data Exchange (ETDEWEB)

    Levitskaia, Tatiana G.; Morris, James E.; Creim, Jeffrey A.; Woodstock, Angela D.; Luders, Teresa; Curry, Terry L.; Thrall, Karla D.

    2010-01-01

    The reported investigation provides a comparison of the oral decorporation efficacy of L-glutathione (GSH), L-cysteine (Cys), and a liposomal GSH formulation (ReadiSorb) toward systemic cobalt-60 (60Co) to that observed following intravenous administration of GSH and Cys in F344 rats. L-histidine (His) was tested intravenously to compare in vivo efficacy of the aminothiol GSH and Cys chelators with that of aminoimidazole (His) chelator. 60Co was administered to animals by intravenous injection, followed by intravenous or oral gavage doses of a chelator repeated at 24 hour intervals for a total of 5 doses. The results suggest that GSH and Cys are potent decorporation agents for 60Co in the rat model, although the efficacy of treatment depends largely on systemic availability of a chelator. The intravenous GSH or Cys were most effective in reducing tissue 60Co levels and in increasing excretion of radioactivity compared to control animals. Liposomal encapsulation was found to markedly enhance the oral bioavailability of GSH compared to non-formulated GSH. Oral administration of ReadiSorb reduced 60Co levels in nearly all tissues by 12-43% compared to that observed for non-formulated GSH. Efficacy of oral Cys was only slightly reduced in comparison with intravenous Cys. Further studies to optimize the dosing regimen in order to maximize decorporation efficiency are warranted.

  14. Study of gamma radiation from {sup 60}Co effects on Apis mellifera venom: biochemical, pharmacological and immunological aspects; Estudo dos efeitos da radiacao gama de {sup 60}Co na peconha de Apis mellifera: aspectos bioquimicos, farmacologicos e imunologicos

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Helena

    2001-07-01

    Africanized honeybees are very common insects in Brazil and frequently cause accidents followed by important immunological reactions and even deaths. Their venoms are composed of a complex mixture of substances of general biological actions. Ionizing radiation is able to modify molecular structures affecting the biological properties of proteins. It decreases toxic and enzymatic activities and so, it appears promising as a venom detoxification tool. The main objective of this work was to study the effects of gamma radiation on bee venom, regarding biochemical, pharmacological and immunological aspects. Africanized Apis mellifera whole venom (2 mg/ml) in 0.15 M NaCl solution was irradiated with 2 kGy in a {sup 60}Co source. Native and irradiated bee venoms were submitted to high performance size exclusion chromatography (Tosohaas G2000SW column), high performance reversed phase chromatography in a C-18 column under water/acetonitrile gradient, SDS-PAGE. For both venoms studies have been carried out in UV absorption spectrum, protein concentration, hemolytic activity, and PLA{sub 2} activity analysis, lethality assay (LD{sub 50}). Biodistribution studies was carried out after labelling native and irradiated bee venom with {sup 99m}Tc. The results showed that gamma radiation did not change the protein concentration nor its immunogenicity, although it could be observed that irradiated bee venom UV spectrum and SDS-PAGE profile presented differences when compared to native bee venom. This suggests that some structural alterations in bee venom components could have occurred after irradiation. HPLC-RP profiles showed that gamma radiation could have caused conformational changes, such as unfolding of molecule chains, changing their hydrophobic groups exposuring. The hemolytic and the PLA{sub 2} activities of irradiated bee venom were smaller than the native ones. The gamma radiation diminished the toxicity of bee venom, but did not abolish its bioactivity, like hemolysis

  15. 60Co contamination in recycled steel resulting in elevated civilian radiation doses: causes and challenges.

    Science.gov (United States)

    Chang, W P; Chan, C C; Wang, J D

    1997-09-01

    Since late 1992, more than 100 building complexes containing public and private schools and nearly 1,000 apartments have been identified in Taiwan with elevated levels of gamma-radiation from construction steel contaminated with 60Co. Due to improper handling of 60Co contaminated scrap steel in late 1982 and 1983, contaminated construction materials have been widely distributed throughout the country. These contaminated construction materials have generated elevated radiation exposures to members of the public in Taiwan. As of early 1996, more than 4,000 people, including young students, have been identified as receiving more than 1 mSv y(-1) above the local background for up to 12 y. This report provides a detailed discussion of the sources of the 60Co contamination in construction steel, its discovery in the building complexes, and preliminary evaluation and remediation activities.

  16. Validation of dose-response curve of CRCN-NE - Regional Center for Nuclear Sciences from Northeast Brazil for {sup 60}Co: preliminary results; Validacao da curva dose-resposta do CRCN-NE para {sup 60}Co: resultados preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, Julyanne C.G.; Mendes, Mariana E.; Hwang, Suy F.; Lima, Fabiana F. [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Santos, Neide, E-mail: july_cgm@yahoo.com.br [Universidade Federal de Pernambuco (CCB/UFPE), Recife, PE (Brazil). Departamento de Genetica

    2014-07-01

    The cytogenetic study has the chromosomal alterations as biomarkers in absorbed dose estimation by the body of individuals involved in exposure to ionizing radiation by interpreting a dose response calibration curve. Since the development of the technique to the analysis of data, you can see protocol characteristics, leading the International Atomic Energy Agency indicate that any laboratory with intention to carry out biological dosimetry establish their own calibration curves. The Biological Dosimetry Laboratory of the Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN), Brazil, recently established the calibration curve related to gamma radiation ({sup 60}Co). Thus, this work aimed to start the validation of this calibration curve from samples of three different blood donors which were irradiated with an absorbed known single dose of 1 Gy. Samples were exposed to {sup 60}Co source (Glaucoma 220) located in the Department of Nuclear Energy (DEN/UFPE). After fixation with methanol and acetic acid and 5% Giemsa staining, the frequency of chromosomal alterations (dicentric chromosomes, acentric rings and fragments) were established from reading of 500 metaphases per sample and doses were estimated using Dose Estimate program. The results showed that, using the dose-response curve calibration for dicentrics, the dose absorbed estimated for the three individuals ranged from 0.891 - 1,089Gy, taking into account the range of confidence of 95%. By using the dose-response curve for dicentrics added to rings and for the same interval of confidence the doses ranged from 0,849 - 1,081Gy. Thus, the estimative encompassed known absorbed dose the three individuals in confidence interval of 95%. These preliminary results seems to demonstrate that dicentric dose-response curves and dicentrics plus rings established by CRCN-NE / CNEN are valid for dose estimation in exposed individuals. This validation will continue with samples from different individuals at different doses.

  17. Use of {sup 60}Co gamma radiation in increased levels of total polyphenol extracts of bark of Schinus terebinthifolius Raddi

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo H.F.; Silva, Edvane B.; Silva, Hianna A.M.F.; Amorin, Elba L.C.; Peixoto, Tadeu J.S.; Yara, Ricardo; Lima, Claudia S.A., E-mail: santosghf@hotmail.com, E-mail: edvborges@yahoo.com, E-mail: amdemelo@hotmail.com, E-mail: claudia.salima@gmail.com, E-mail: ricardo.yara@gmail.com, E-mail: tadeu1903@yahoo.com.br, E-mail: elba@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2013-07-01

    Schinus terebinthifolius Raddi (Anacardiaceae) is well known as sources of phenolic compounds. Known as mastic pepper, red pepper tree is a plant native to midsize coast of Brazil. Some of its structures have proven antibacterial, anti-inflammatory, antifungal and healing. The aim of this study was to evaluate the difference in the phenol contents of crude extracts that were measured after irradiating the barks of S. terebinthifolius using gamma radiation from {sup 60}Co. The crude extract were divided into a control group and eight experimental groups, which were separated based on the doses of gamma radiation to which they were exposed: 2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 20.0 and 50.0 kGy (Assays were performed in triplicate). The results allow observe that gamma radiation promoted in extracts of bark of S. terebinthifolius, many percents increase (p> 0.05) of total polyphenol content between 2.5 kGy (41.93%) and 50.0 kGy (44.52%) compared to 0 kGy (30.07%), with the same gradual to 10.0 kGy, and reaching peak maximum at 10.0 kGy (68.44%). However, the study puts the process of gamma radiation from {sup 60}Co as an alternative significant increase in the percentage of some natural substances of plant material, and subsequently contribute to the augmentation of various therapeutic applications to which they are assigned. (author)

  18. [Effect of tonicity of the medium on the sensitivity of Escherichia coli bacteria to gamma-quantum 60Co, ultrasound and hyperthermia].

    Science.gov (United States)

    Morozov, I I; Petin, V G; Morozova, G V

    1998-01-01

    The cell lethality and permeability induced in Escherichia coli B/r and Escherichia coli BS-1 by 60Co gamma-ray irradiation, ultrasound and hyperthermia in media containing different concentrations of NaCl have been investigated. It was shown that independently from the nature of damaging factors hypotonic media increase while hypertonic media in certain range of osmolyte concentration decrease sensitivity of cells to action of this factors. It was proposed that discovered phenomenology was caused by salt modification of status of the cell osmotic homeostasis destabilizing by ionizing radiation, ultrasound or hyperthermia and was not related with the system of dark repair of DNA.

  19. Monte Carlo Dosimetry of the 60Co BEBIG High Dose Rate for Brachytherapy.

    Directory of Open Access Journals (Sweden)

    Luciana Tourinho Campos

    Full Text Available The use of high-dose-rate brachytherapy is currently a widespread practice worldwide. The most common isotope source is 192Ir, but 60Co is also becoming available for HDR. One of main advantages of 60Co compared to 192Ir is the economic and practical benefit because of its longer half-live, which is 5.27 years. Recently, Eckert & Ziegler BEBIG, Germany, introduced a new afterloading brachytherapy machine (MultiSource®; it has the option to use either the 60Co or 192Ir HDR source. The source for the Monte Carlo calculations is the new 60Co source (model Co0.A86, which is referred to as the new BEBIG 60Co HDR source and is a modified version of the 60Co source (model GK60M21, which is also from BEBIG.The purpose of this work is to obtain the dosimetry parameters in accordance with the AAPM TG-43U1 formalism with Monte Carlo calculations regarding the BEBIG 60Co high-dose-rate brachytherapy to investigate the required treatment-planning parameters. The geometric design and material details of the source was provided by the manufacturer and was used to define the Monte Carlo geometry. To validate the source geometry, a few dosimetry parameters had to be calculated according to the AAPM TG-43U1 formalism. The dosimetry studies included the calculation of the air kerma strength Sk, collision kerma in water along the transverse axis with an unbounded phantom, dose rate constant and radial dose function. The Monte Carlo code system that was used was EGSnrc with a new cavity code, which is a part of EGS++ that allows calculating the radial dose function around the source. The spectrum to simulate 60Co was composed of two photon energies, 1.17 and 1.33 MeV. Only the gamma part of the spectrum was used; the contribution of the electrons to the dose is negligible because of the full absorption by the stainless-steel wall around the metallic 60Co. The XCOM photon cross-section library was used in subsequent simulations, and the photoelectric effect, pair

  20. Monte Carlo Dosimetry of the 60Co BEBIG High Dose Rate for Brachytherapy

    Science.gov (United States)

    Campos, Luciana Tourinho; de Almeida, Carlos Eduardo Veloso

    2015-01-01

    Introduction The use of high-dose-rate brachytherapy is currently a widespread practice worldwide. The most common isotope source is 192Ir, but 60Co is also becoming available for HDR. One of main advantages of 60Co compared to 192Ir is the economic and practical benefit because of its longer half-live, which is 5.27 years. Recently, Eckert & Ziegler BEBIG, Germany, introduced a new afterloading brachytherapy machine (MultiSource®); it has the option to use either the 60Co or 192Ir HDR source. The source for the Monte Carlo calculations is the new 60Co source (model Co0.A86), which is referred to as the new BEBIG 60Co HDR source and is a modified version of the 60Co source (model GK60M21), which is also from BEBIG. Objective and Methods The purpose of this work is to obtain the dosimetry parameters in accordance with the AAPM TG-43U1 formalism with Monte Carlo calculations regarding the BEBIG 60Co high-dose-rate brachytherapy to investigate the required treatment-planning parameters. The geometric design and material details of the source was provided by the manufacturer and was used to define the Monte Carlo geometry. To validate the source geometry, a few dosimetry parameters had to be calculated according to the AAPM TG-43U1 formalism. The dosimetry studies included the calculation of the air kerma strength Sk, collision kerma in water along the transverse axis with an unbounded phantom, dose rate constant and radial dose function. The Monte Carlo code system that was used was EGSnrc with a new cavity code, which is a part of EGS++ that allows calculating the radial dose function around the source. The spectrum to simulate 60Co was composed of two photon energies, 1.17 and 1.33 MeV. Only the gamma part of the spectrum was used; the contribution of the electrons to the dose is negligible because of the full absorption by the stainless-steel wall around the metallic 60Co. The XCOM photon cross-section library was used in subsequent simulations, and the

  1. Resposta de sementes de amendoim a diferentes doses de radiação gama (60Co Response of peanut seeds to different levels of gamma radiation (60Co

    Directory of Open Access Journals (Sweden)

    Tatiana da S. Santos

    2010-10-01

    Full Text Available A radiação gama, proveniente da fonte de 60Co, é bastante utilizada para esterilização, visando a prevenção da decomposição e a toxidez de origem microbiana em diversos produtos. O grau de radiossensibilidade de um embrião vegetal depende da espécie, do estágio de seu desenvolvimento durante a radiação, da dose empregada e do critério usado para medir o efeito biológico, sendo comumente utilizado o teste de germinação. Objetivou-se, com este trabalho, estudar a sensibilidade do amendoim a radiação gama e seus efeitos na germinação, no vigor e na micoflora das sementes da cultivar BRS Havana, irradiadas com uma fonte de 60Co, tipo gammacell, com taxa de dosagem de 12,5 kGy h-1. As doses testadas em kGy foram as seguintes: 0; 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 6,0; 9,0; 12,0; 15,0; 18,0; 21,0 e 24,0. Com os resultados obtidos, concluiu-se que as doses acima de 3,0 kGy prejudicaram a viabilidade das sementes e as doses acima de 12 kGy comprometeram totalmente o vigor e a germinação das sementes de amendoim. A radiação a partir da dose 2,0 kGy eliminou os fungos Aspergillus flavus e Aspergillus niger e, a partir da dose 3,0 kGy, eliminou o Aspergillus glaucus. O Penicilium spp. permaneceu em mais de 30% das sementes em todos os tratamentos com radiação, não sendo eliminado até a dose de 24 kGy.The gamma radiation from 60Co source is widely used for sterilization aiming at preventing decomposition and toxicity from microbes in several products. The degree of radiosensitvity of a plant embryo depends on the species, the development stage during radiation, doses used and the criteria used to measure the biological effect, the germination test, being commonly used.This work aimed to study the peanut sensitivity to gamma radiation and its effects in the germination, in the vigour and seeds microflora of cultivar BRS Havana, irradiated with 60Co source, type gammacell with rate of dosage of 12.5 kGy h-1. The tested doses were the

  2. Clinic based transfer of the N(D,W)(60Co) calibration coefficient using a linear accelerator.

    Science.gov (United States)

    Abdel-Rahman, W; Evans, M D C; Serré, L; McCaffrey, J P; Podgorsak, E B; Seuntjens, J P

    2009-03-01

    Ionization chambers used for reference dosimetry require a local secondary standard ionization chamber with a 60Co absorbed dose to water calibration coefficient N(D,W)(60Co) traceable to a national primary standards dosimetry laboratory or an accredited secondary dosimetry calibration laboratory. Clinic based (in-house) transfer of this coefficient to tertiary reference ionization chambers has traditionally been accomplished with chamber cross calibration in water using a 60Co beam; however, access to 60Co teletherapy machines has become increasingly limited for clinic based physicists. In this work, the accuracy of alternative methods of transferring the N(D,W)(60Co) calibration coefficient using 6 and 18 MV photon beams from a linear accelerator in lieu of 60Co has been investigated for five different setups and four commonly used chamber types.

  3. Optimization of the cryopreservation of biological resources, Toxoplasma gondii tachyzoites, using flow cytometry.

    Science.gov (United States)

    Mzabi, Alexandre; Escotte-Binet, Sandie; Le Naour, Richard; Ortis, Naïma; Audonnet, Sandra; Dardé, Marie-Laure; Aubert, Dominique; Villena, Isabelle

    2015-12-01

    The conservation of Toxoplasma gondii strains isolated from humans and animals is essential for conducting studies on Toxoplasma. Conservation is the main function of the French Biological Toxoplasma Resource Centre (BRC Toxoplasma, France, http://www.toxocrb.com/). In this study, we have determined the suitability of a standard cryopreservation methodology for different Toxoplasma strains using the viability of tachyzoites assayed by flow cytometry with dual fluorescent labelling (calcein acetoxymethyl ester and propidium iodide) of tachyzoites. This method provides a comparative quantitative assessment of viability after thawing. The results helped to define and refine quality criteria before tachyzoite cryopreservation and optimization of the cryopreservation parameters. The optimized cryopreservation method uses a volume of 1.0 mL containing 8 × 10(6) tachyzoites, in Iscove's Modified Dulbecco's Medium (IMDM) containing 10% foetal calf serum (FCS). The cryoprotectant additive is 10% v/v Me2SO without incubation. A cooling rate of ∼1 °C/min to -80 °C followed, after 48 h, by storage in liquid nitrogen. Thawing was performed using a 37 °C water bath that produced a warming rate of ∼100 °C/min, and samples were then diluted 1:5 in IMDM with 5% FCS, and centrifuged and resuspended for viability assessment.

  4. INTERFERON-GAMMA STIMULATING ACTIVITIES OF THE FRACTIONATED NEOSPORA CANINUM TACHYZOITE LYSATE

    Science.gov (United States)

    Neospora caninum is an obligate intracellular protozoan parasite, causing bovine abortion worldwide. Our recent research showed that N. caninum tachyzoite lysate elicits production of the T cell cytokine interferon-gamma (IFN-g) by both bovine and murine T cells, which may be critical to host protec...

  5. Melatonin attenuates (60) Co γ-ray-induced hematopoietic, immunological and gastrointestinal injuries in C57BL/6 male mice.

    Science.gov (United States)

    Khan, Shahanshah; Adhikari, Jawahar Singh; Rizvi, Moshahid Alam; Chaudhury, Nabo Kumar

    2017-02-01

    Protection of hematopoietic, immunological, and gastrointestinal injuries from deleterious effects of ionizing radiation is prime rational for developing radioprotector. The objective of this study, therefore, was to evaluate the radioprotective potential of melatonin against damaging effects of radiation-induced hematopoietic, immunological, and gastrointestinal injuries in mice. C57BL/6 male mice were intraperitoneally administered with melatonin (50-150 mg/kg) 30 min prior to whole-body radiation exposure of 5 and 7.5 Gy using (60) Co-teletherapy unit. Thirty-day survival against 7.5 Gy was monitored. Melatonin (100 mg/kg) pretreatment showed 100% survival against 7.5 Gy radiation dose. Melatonin pretreatment expanded femoral HPSCs, and inhibited spleenocyte DNA strands breaks and apoptosis in irradiated mice. At this time, it also protected radiation-induced loss of T cell sub-populations in spleen. In addition, melatonin pretreatment enhanced crypts regeneration and increased villi number and length in irradiated mice. Translocation of gut bacteria to spleen, liver and kidney were controlled in irradiated mice pretreated with melatonin. Radiation-induced gastrointestinal DNA strand breaks, lipid peroxidation, and expression of proapoptotic-p53, Bax, and antiapoptotic-Bcl-xL proteins were reversed in melatonin pretreated mice. This increase of Bcl-xL was associated with the decrease of Bax/Bcl-xL ratio. ABTS and DPPH radical assays revealed that melatonin treatment alleviated total antioxidant capacity in hematopoietic and gastrointestinal tissues. Present study demonstrated that melatonin pretreatment was able to prevent hematopoietic, immunological, and gastrointestinal radiation-induced injury, therefore, overcoming lethality in mice. These results suggest potential of melatonin in developing radioprotector for protection of bone marrow, spleen, and gastrointestine in planned radiation exposure scenarios including radiotherapy. © 2016 Wiley

  6. History and prospects of irradiation treatment of sewage sludge

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    This paper presents a survey of irradiation treatment of sewage sludge in the world.Since the first sludge irradiation plant was built in Geiselbullach, West Germany in 1973 which used 60Co as irradiation source, many sludge irradiators were constructed in USA, India, Japan, Canada, Poland and so on, which used 60Co, 137Cs or electron beam as irradiation sources.Some basic researches on irradiation treatment of sewage sludge are, respectively, reviewed, including optimization of irradiation parameters, synergistic effect of radiation with heat, oxygenation, irradiation-composting and potential applications of treated sludge.Some proposals have been suggested for further development of this technology.

  7. Cyst Formation from Virulent RH Strain of Toxoplasma gondii Tachyzoite: In Vitro Cultivation

    Directory of Open Access Journals (Sweden)

    Mahboobeh SALIMI

    2016-03-01

    Full Text Available Background: This study was performed to induce conversion of RH strain tachyzoites of Toxoplasma gondii to bradyzoites by pH changing of the cul­ture medium.Methods: HeLa cell monolayers were infected at a 1:1 tachyzoite to cell ratio. Four hours after infection, the culture medium was removed and re­placed with culture medium and 5% FCS, adjusted to pH 8 with NaOH. The culture was maintained at 37 °C without CO2 until the end of the ex­periment. Cyst-like structures were collected and stained with periodic acid schiff (PAS staining method. The soluble antigens of cyst-like structures of RH strain, in addition to RH tachyzoite, bradyzoites of avirulent Tehran strain and uninfected HeLa cells were electrophoresed on 12.5% poly­acrylamide gel. The gel was stained by coomassie brilliant blue R-250.Results: Four days after infection of HeLa cells with tachyzoites of T. gondii, RH strain, cyst- like structures were noticed and stained with PAS. In the SDS-PAGE, protein bands of these structures had some differences with tachyzoites of RH strain, but there was quite similarity between pro­tein bands of these structures and tissue cysts (bradyzoites of Tehran strains. P34 and P36 (bradyzoite-specific proteins were observed only in T. gondii bradyzoites of RH (cyst like structures and bradyzoites of Tehran strains.Conclusion: Alkalization of culture medium to pH 8 induced expression of bradyzoite- specific proteins and production of RH cysts in cell culture.

  8. Evaluation of fruit productivity and quality in Hass avocado submitted to {sup 60}Co gamma radiation; Evaluacion de productividad y calidad de fruta en aguacate Hass sometido a radiacion gamma de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Cruz T, E. De la; Ibanez P, J.; Mijares O, P.; Garcia A, J.M. [Instituto nacional de Investigaciones Nucleares, Departamento de Biologia, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    Evaluation of productivity, postharvest behavior and fruit quality was performed on four years Hass avocado trees irradiated with {sup 60} Co gamma rays in doses of 5, 10, 15, 20 and 25 Gy, established in the ''La Labor'' Experimental Center of the Centro de Investigaciones Cientificas y Tecnologias del Aguacate en el Estado de Mexico (CICTAMEX) at Temascaltepec Mexico. Productivity had a significant increase in the dose of 15 Gy being the average number of fruits nearly 400 % more than the control at fruit setting, being such difference reduced at fruit harvesting to 300 %. In regard to postharvest performance, the respiration index (mg CO{sub 2}/kg/hr) did not show significant differences among treatments. Also others variables such as physiological weight losses, texture, maturity pattern, and sensorial tests (color, flavor, aroma, texture) were not different in regard to the control. This mean that radiation has altered productivity but not the quality and postharvest behavior of fruits. (Author)

  9. Toxoplasma gondii: effects of {sup 60} Co ionizing radiation in the viability and infectivity, detected in vitro in LLC-MK2 cells and in vivo in C57BL/6J mice

    Energy Technology Data Exchange (ETDEWEB)

    Hiramoto, Roberto M.; Almeida, Beatriz S.V.; Cardoso, Roselaine P.A.; Andrade Junior, Heitor F. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1997-12-01

    Toxoplasmosis, caused by Toxoplasma gondii, promotes devasting disease in fetus and AIDS patients. The longlife immunity of natural infection is inefficient in eliminate tissue infective cysts. Few immunization programs were tested, mostly with attenuated strains. Ionizing radiation were used with successful in vaccine production, without reproductive ability with a relatively normal physiology until reproduction. Here, we tested several schedules of {sup 60} Co irradiation of tachzoites from RH strain of T. gondii, from peritoneal exudate or suspensions of LLC-MK2 infected cells, to optimize the viability and sterility of the irradiated agents. The tachzoites were exposed to 50, 100 and 200 Gy in a GammaCell 220 at 366 Gy/h. The viability was tested by motility, integrity and Trypan Blue dye exclusion. All irradiation schedules maintained a high (>90%) viability of the parasites. Dilutions were injected in C57Bl/6j mice with induction of specific antibodies, no clinical disease but uncertain sterility. Infection of LLC--MK2 cells showed that viable and reproductive parasites were often found in 50 Gy irradiated cells, rarely found in 100 Gy irradiated cells, rarely found in 100 Gy irradied cells, with no growth occuring with 200 Gy irradiated tachzoites. Our data show that 200 Gy {sup 60} Co irradiation blocks the reproductive capacity without affecting the short term viability of tachzoites of T. gondii. (author). 11 refs., 1 fig.

  10. Experimental and Monte Carlo evaluation of an ionization chamber in a {sup 60}Co beam

    Energy Technology Data Exchange (ETDEWEB)

    Perini, Ana P.; Neves, Lucio Pereira, E-mail: anapaula.perini@ufu.br [Universidade Federal de Uberlandia (INFIS/UFU), MG (Brazil). Instituto de Fisica; Santos, William S.; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Recently a special parallel-plate ionization chamber was developed and characterized at the Instituto de Pesquisas Energeticas e Nucleares. The operational tests presented results within the recommended limits. In order to determine the influence of some components of the ionization chamber on its response, Monte Carlo simulations were carried out. The experimental and simulation results pointed out that the dosimeter evaluated in the present work has favorable properties to be applied to {sup 60}Co dosimetry at calibration laboratories. (author)

  11. Experimental and Monte Carlo evaluation of an ionization chamber in a 60Co beam

    Science.gov (United States)

    Perini, A. P.; Neves, L. P.; Santos, W. S.; Caldas, L. V. E.

    2016-07-01

    Recently a special parallel-plate ionization chamber was developed and characterized at the Instituto de Pesquisas Energeticas e Nucleares. The operational tests presented results within the recommended limits. In order to determine the influence of some components of the ionization chamber on its response, Monte Carlo simulations were carried out. The experimental and simulation results pointed out that the dosimeter evaluated in the present work has favorable properties to be applied to 60Co dosimetry at calibration laboratories.

  12. Development and characterization of a new graphite ionization chamber for dosimetry of {sup 60}Co beams

    Energy Technology Data Exchange (ETDEWEB)

    Neves, Lucio Pereira; Perini, Ana Paula; Santos, William de Souza; Caldas, Linda V.E., E-mail: lpneves@ipen.br, E-mail: aperini@ipen.br, E-mail: wssantos@ipen.br, E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    Ionization chambers are the most employed dosimeters for precise measurements, as those required in radiotherapy. In this work, a new graphite ionization chamber was developed and characterized in order to compose a primary standard system for the beam dosimetry of the {sup 60}Co sources. This dosimeter is a cylindrical type ionization chamber, with walls and collecting electrode made of high-purity graphite, and the insulators and stem made of Teflon®. The walls are 3.0 mm thick, and it has a sensitive volume of 1.40 cm{sup 3}. The characterization was divided in two steps: experimental and Monte Carlo evaluations. This new dosimeter was evaluated in relation to its saturation curve, ion collection efficiency, polarity effect, short- and medium-term stabilities, leakage current, stabilization time, linearity of response and angular dependence. All results presented values within the established limits. The second part of the characterization process involved the determination of the correction factors, obtained by Monte Carlo simulations. Comparing these correction factors values with those from other primary standard laboratories, the highest differences were those for the wall and stem correction factors. The air-kerma rate of the {sup 60}Co source was determined with this new dosimeter and with the IPEN standard system, presenting a difference of 1.7%. These results indicate that this new dosimeter may be used as a primary standard system for {sup 60}Co gamma beams. (author)

  13. 60 Co-γ辐射对白刺花幼苗生理的影响%Effect of 60 Co-γ lrradiation on Physiological Characteristics of Sophora viciifoliaSeedlings

    Institute of Scientific and Technical Information of China (English)

    李凤涛; 赵丽丽; 王普昶; 陈超; 吴小丽

    2015-01-01

    The relative physiological indexes of seedlings from S. viciifolia seeds irradiated by different dosage of 60 Co-γ treatment and the mutation effect of S. viciifolia seedlings was comprehensively evaluated by principal component analysis(PCA)and membership function analysis to provide the theoretical basis for breeding of S.viciifolia variety. The results show that chlorophyll,MDA,soluble sugar and soluble protein content and POD activity of S. viciifolia seedlings both represent a first rising and then decline trend with increase of irradiation dosage but the SOD activity and proline content gradually increase with increase of irradiation dosage. The different irradiation treatment can improve photosynthesis of S. viciifolia seedlings. MDA content of seedlings of S. viciifolia seeds treated with 60 kR is up to 59. 42 μmol/ g,significantly higher than other treatments. The POD and SOD activity of seedlings of S. viciifolia seeds treated with 100 kR and 120 kR reaches 596. 92 U/(g·min)and 178. 04 U/ g FW respectively. The soluble sugar and soluble protein content of seedlings of S. viciifolia seeds treated with 100 kR is the maximum. The proline content of seedlings of S. viciifolia seeds treated with 120 kR is seedlings’ physiological indexes affected by irradiation dosage is 120 kR ﹥ 100 kR ﹥ 80 kR ﹥ 140 kR ﹥ 60 kR ﹥ 40 kR ﹥ 20 kR﹥0 kR and the optimum irradiation dosage for S. viciifolia seeds is 80 kR,100 kR and 120 kR.%为白刺花新品种的培育提供理论依据,通过设置不同辐照剂量处理,以经辐照处理的白刺花种子培养的幼苗为研究对象,测定60 Co-γ辐射白刺花幼苗的相关生理指标,采用主成分分析和隶属函数分析法综合评价60 Co-γ射线对白刺花幼苗的诱变效果。结果表明:随着辐射剂量的增加,白刺花的叶绿素、MDA、可溶性糖和可溶性蛋白含量以及 POD 活性呈先升高后降低变化趋势,SOD 活性和脯氨酸含量则随着辐射

  14. Behavior of 60Co and 134Cs in a Canadian Shield lake over 5 years.

    Science.gov (United States)

    Bird, G A; Schwartz, W J; Motycka, M; Rosentreter, J

    1998-04-08

    Radionuclides were added to the anoxic hypolimnion of a Canadian Shield lake to simulate the nuclear fuel waste disposal scenario where radionuclides might enter the bottom waters of a lake. The radionuclides remained in the hypolimnion until lake mixing at autumn turnover after which 60Co was rapidly lost and 134Cs was slowly lost from the water. Only 0.4% of the 60Co and 0.6% of the 134Cs remained in the water at year 5. Highest concentrations occurred in periphyton and filter feeders, Holopedium gibberum and clams (Anodonata grandis grandis). From maximum annual concentrations in clam tissues, it was estimated that the availability of 60Co for uptake had a half-time (t1/2) of 835 days in the lake, whereas that for 134Cs was 780 days. Loss rate coefficients, k, for the radionuclides from taxa ranged from 0.0008 to 0.0043 day-1 (t1/2 = 161-866 days) for 60Co and from 0.0009 to 0.005 day-1 (t1/2 = 139-770 days) for 134Cs. Cobalt-60 concentrations in forage fish were low, whereas 134Cs concentrations increased over the first year or two, then slowly declined. On the basis of k values measured for forage fish, the biological half-time of 134Cs in forage fish ranged from 428 to 630 days. Maximum 134Cs concentrations in forage fish were higher following hypolimnetic addition than epilimnetic addition. Relatively high 134Cs concentrations in periphyton at year 5 point to the importance of benthic pathways in the recycling of contaminants to higher trophic levels. The presence of 134Cs in biota 5 years after the addition, long after concentrations were no longer detectable in surface waters, is evidence of the persistence of Cs in aquatic systems. The k values (or t1/2 values) for the loss of 60Co and 134Cs from water and their uptake and loss from biota can be used to establish parameter values for assessment models. The results demonstrate that assessment models should account for the release of radionuclides from sediment and their subsequent recycling in the food

  15. Behavior of the sorption of {sup 60} Co in aqueous solution on inorganic materials as function of p H; Comportamiento de la sorcion del {sup 60} Co en solucion acuosa sobre materiales inorganicos como una funcion del pH

    Energy Technology Data Exchange (ETDEWEB)

    Granados, F.; Bulbulian, S.; Solache R, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Bertin, V. [UAM-I, 09340 Mexico D.F. (Mexico)

    2004-07-01

    The sorption of the {sup 60} Co is evaluated in aqueous solution on Mg O, MnO{sub 2}, TiO{sub 2}, Sn O, activated carbon and hydrotalcite calcined as a function of the p H, using the method for lots and quantifying at the {sup 60} Co for gamma spectrometry. Likewise it was explained the one behavior of the sorption of the {sup 60} Co in the materials with base in the chemical species of this radioactive isotope in aqueous solution. The chemical species of the {sup 60} Co in solution were identified by electrophoresis of high voltage for the different p H values. It was found that under the experimental conditions, the {sup 60} Co showed a significant sorption on MnO{sup 2}, TiO{sup 2} and activated carbon. On the other hand, in Mg O, Sn O and calcined hydrotalcite also was observed a sorption, although in smaller quantities. The studied hydrated metallic oxides retained the {sup 60} Co for ion exchange via. It was found that the {sup 60} Co was present as a cationic specie to p H 1, 3, 5 and 7 and like a neutral specie to alkaline p H. (Author)

  16. Effect of the ionizing radiation of the {sup 60}Co on the radiological properties of guar gum and carboxymethylcellulose for the food industry use; Efeito da radiacao ionizante de {sup 60}Co sobre propriedades radiologicas da goma guar e carboximetilcelulose para uso na industria alimenticia

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Fernando Fabris; Mastro, Nelida Lucia del [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2002-07-01

    Hydrosoluble polysaccharides or gums are long chain polymers that dissolve or disperse in water. When added to foods, they change rheological characteristics, stabilize emulsions, promote particle suspension, control crystallization and inhibit sineresis of processed foods. Guar gum is an hydro soluble polysaccharide obtained from the seed of Cyamopsis tetragonolobus. Carboxy-methylcellulose (CMC) is an homopolisaccharide prepared by the treatment of alkaline cellulose with sodium monochloroacetate. This work presents the results of the study of radiation effects on the viscosity of guar gum and CMC used for the food industry when irradiated with {sup 60} Co ionizing radiation. (author)

  17. Detection and temporal variation of (60)Co in the digestive glands of the common octopus, Octopus vulgaris, in the East China Sea.

    Science.gov (United States)

    Morita, Takami; Otosaka, Shigeyoshi; Fujimoto, Ken; Nishiuchi, Kou; Kimoto, Katsunori; Yamada, Haruya; Kasai, Hiromi; Minakawa, Masayuki; Yoshida, Katsuhiko

    2010-08-01

    (60)Co were detected in common octopus specimens collected in the East China Sea in 1996-2005. The source of (60)Co has remained unclear yet. Stable isotope analyses showed that there was no difference in stable Co concentrations between octopus samples with (60)Co and without (60)Co. This result showed that the stable Co in the digestive gland of octopus potentially did not include a trace amount of (60)Co and the source of (60)Co existed independently. Furthermore, investigations of octopus in other area and other species indicated that the origin of the source of (60)Co occurred locally in the restricted area in the East China Sea and not in the coastal area of Japan. Concentrations of (60)Co have annually decreased with shorter half-life than the physical half-life. This decrease tendency suggests that the sources of (60)Co were identical and were temporary dumped into the East China Sea as a solid waste.

  18. Development and evaluation of a technique for in vivo monitoring of {sup 60}Co in the lungs

    Energy Technology Data Exchange (ETDEWEB)

    Mello, J.Q. de; Lucena, E.A.; Dantas, A.L.A.; Dantas, B.M., E-mail: bmdantas@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    {sup 60}Co is a fission product of {sup 235}U and represents a risk of internal exposure of workers in nuclear power plants, especially those involved in the maintenance of potentially contaminated parts and equipment. The control of {sup 60}Co intake by inhalation can be performed through in vivo monitoring. This work describes the evaluation of a technique through the minimum detectable activity and the corresponding minimum detectable effective doses, based on biokinetic and dosimetric models of {sup 60}Co in the human body. The results allow to state that the technique is suitable either for monitoring of occupational exposures or evaluation of accidental intakes. (author)

  19. The effect of 60Co-gamma radio-sterilization on Boswellia carterii essential oil composition

    OpenAIRE

    P. Badr; S. Daneshamouz; A.A. Mohammadi; A.R. Akbarizadeh; Afsharypuor, S.

    2016-01-01

    Background and objectives:Gamma-irradiation is used vastly for both decontamination and sterilization of natural products; but these high-energy rays can affect heat-sensitive essential oils. Methods: The oleo-gum-resin of Boswellia carterii (Burseraceae) was sterilized by γ-irradiation at dose 30 KGy. The essential oils obtained by hydrodistillation of non-irradiated Boswellia (NIB) and irradiated Boswellia (IB) were analyzed by GC/MS and the changes were compared. The structure of octyl ace...

  20. Comparison between a commercial and homemade ionization chamber for dosimetry of {sup 60}Co beams

    Energy Technology Data Exchange (ETDEWEB)

    Neves, Lucio P.; Perini, Ana P.; Caldas, Linda V.E., E-mail: lpneves@ipen.b, E-mail: aperini@ipen.b, E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The Calibration Laboratory at IPEN/CNEN (LCI) has developed several ionization detectors for dosimetry in diagnostic radiology, radiation protection and radiotherapy. Recently, a cylindrical ionization chamber, with a sensitive volume of 1.06cm{sup 3}, was developed, and several tests were performed to characterize this ionization chamber for radiotherapy level. The results showed that its performance was within the recommended international limits. In order to complement the studies regarding the response of this ionization chamber, in this work, the chamber response was compared with that of a commercial ionization chamber Farmer PTW, model TN30011-1. The ionization chamber produced at LCI is made of PVC and PMMA. A special build-up cap for {sup 60}Co beams was made of acrylic, with 4.00 mm thickness. All tests of both ionization chambers were performed under the same conditions, allowing good geometrical reproducibility. The performed tests were: saturation, ion collection efficiency, polarity effect and chamber tilt. The results obtained in this comparison program were all within the international recommendations, and demonstrate a good agreement of the performance of the commercial and the homemade ionization chambers. From this comparison results and from previous data, it is possible to conclude that the ionization chamber produced at IPEN presents usefulness for dosimetric applications at radiotherapy level in {sup 60}Co beams.(author)

  1. Adsorption of {sup 60}Co{sup 2+} on hydrous manganese oxide powder from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Granados Correa, F. [Inst. Nacional de Investigaciones Nucleares, Mexico (Mexico); Univ. Autonoma Metropolitana Iztapalapa, Mexico (Mexico); Jimenez-Becerril, J. [Inst. Nacional de Investigaciones Nucleares, Mexico (Mexico)

    2004-07-01

    Hydrous manganese oxide (HMO) was synthesized and its ability to sorb {sup 60}Co{sup 2+} from aqueous solution was studied under static conditions as a function of contact time, cobalt concentration (10{sup -2}-10{sup -7} M), temperature (303-333 K) and pH of adsorptive solution (2.2-11.4). X-ray diffraction was used in characterization of synthesized HMO. Low concentration of {sup 60}Co{sup 2+} solution, high pH and high temperature were the most favorable conditions for the adsorption process. The results show that the removal process is complete in 40 minutes, obeys a first order rate law and can be described using the Freundlich adsorption model. The standard enthalpy of the system was {delta}H{sup 0} = 12.5 {+-} 0.2 kJ mol{sup -1} and cobalt desorption indicates that the uptake process proceeds via cation exchange. The removal of cobalt ions by HMO appears to be endothermic and irreversible. The values of calculated {delta}G{sup 0} and {delta}S{sup 0} were -17.0 {+-} 3.0 kJ mol{sup -1} and (9.8 {+-} 0.2) x 10{sup -2} kJ K{sup -1} mol{sup -1} respectively, this indicates spontaneity of the process and the degree of freedom of ions is increased by adsorption. (orig.)

  2. Radiation quality of tritium: a comparison with 60Co gamma rays.

    Science.gov (United States)

    Chen, Jing

    2013-09-01

    In a previous study, microdosimetric simulations were performed for tritium uniformly distributed in a medium, and for tritium bound to biologically critical sites of dimensions from 10 nm to 2 µm. Results of local energy density, i.e. energy deposition in microscopic regions, are different for these two cases. Based on the spatial distribution of energy deposition, dose mean lineal energies are calculated for tritium in the forms of tritiated water (HTO) and organically bound tritium (OBT). The dose mean lineal energies of OBT are about a factor of 1.7 higher than those of HTO in a wide range of target dimensions of biological interest. The results are consistent with radiobiological findings that OBT is about twice as effective as HTO. In this study, the same calculations were performed for (60)Co gamma rays in a wide range of target dimensions of biological interest (10 nm to 2 µm). Compared with (60)Co gamma rays, the estimated relative biological effectiveness could vary from 1.3 to 3.5 for HTO, and 2.3 to 5.6 for OBT. The results are consistent with radiobiological findings for various biological endpoints in different biological systems that OBT is about twice as effective as HTO.

  3. Intra-arterial administration of carboplatin plus lower dosage radiation of {sup 60}CO as induction treatment in advanced oral cancer

    Energy Technology Data Exchange (ETDEWEB)

    Okutomi, Tadashi; Kato, Yukihiro; Ichihara, Hideki; Kusunoki, Yukihiro; Hatakeyama, Daijiro; Yokoyama, Kyoko; Tatematsu, Norichika [Gifu Univ. (Japan). School of Medicine; Liu, Jianhua

    2000-11-01

    Conventional pre-operative chemoradiotherapy often causes severe side effects, which may result in interruption of the treatment and delay of decided operation. Carboplatin (CBDCA) is one of the effective chemotherapeutants for head and neck cancer. We treated 23 patients with advanced oral cancers by a combination of intra-arterial administration of Carboplatin and {sup 60}CO radiotherapy. The dosage of Carboplatin was between 20 mg and 35 mg per square meter of body surface. The dosage of external {sup 60}CO irradiation was 2 Gy per day and 30 to 60 Gy in total. We evaluated clinical response, toxicity and survival of this therapy of all the patients. Histologic response was also evaluated in some of them. All cancers responded to the regional chemoradiotherapy and demonstrated remission. Two (8%) completed response rate (CR) and 16 (69%) partial response rate (PR) were achieved. The accumulated five-year overall survival rate by Kaplan-Meier method was 73.9%. Fourteen patients (60.8%) showed no evidence of disease (NED) within five years after the therapy. All patients had stomatitis, but most of them were not so severe. The major hematological toxicity was leukopenia, but it was from mild to moderate and reversible. Our study showed that this therapy provided low toxicity, high clinical and histological response rate. (author)

  4. Dose-effect of nucleoplasmic bridges frequencies in human peripheral blood lymphocytes induced by 60Co γ-rays%60Co γ射线诱导人外周血淋巴细胞核质桥的剂量-效应关系研究

    Institute of Scientific and Technical Information of China (English)

    赵骅; 陆雪; 陈德清; 刘青杰

    2014-01-01

    Objective To establish the analysis criteria of nucleoplasmic bridges (NPB) and a dose-response curve of NPB frequencies in human peripheral blood lymphocytes irradiated by 60Co γ-rays.Methods Human peripheral blood samples were collected from three healthy males,and were irradiated with 0,1,2,3,4,5 and 6 Gy of 60Co γ-rays.A cytokinesis-block micronucleus assay was carried out to analyze NPBs and micronuclei (MN) in binucleated cells.Results NPBs in binucleated cells at each dose level of γ-ray was conformed to the Poisson distribution.The dose-response curve of the γ-ray-induced NPB frequencies in human peripheral lymphocytes followed the linear-quadratic model y =(1.39 × 10-3)x2 + (4.94 × 10-3)x (R2 =0.981,P < 0.05).Conclusions The dose-response curve of NPB frequencies in human peripheral blood lymphocytes induced by 0-6 Gy 60Co γ-rays was established.%目的 确定核质桥判定标准,建立60Co γ射线诱导正常人外周血淋巴细胞中核质桥(NPB)的剂量-效应曲线.方法 用60Co γ射线照射3名健康男性离体外周血,照射剂量分别为0、1、2、3、4、5和6 Gy,剂量率为l Gy/min,采用胞质分裂阻滞微核(CBMN)法进行细胞培养、收获、制片、染色.在光学显微镜下分析双核细胞中NPB及微核(MN).结果 在0~6 Gy 60Co γ射线照射后,人外周血双核淋巴细胞中的NPB符合泊松分布,且NPB频率随吸收剂量增加而增加(H=19.51,P<0.0l),拟合回归方程为线性平方模式y=(1.39×10-3)x2+(4.94×10-3)x (R2 =0.981,P< 0.01).结论 成功建立0~6 Gy60Co γ射线诱导正常人外周血淋巴细胞中NPB的剂量-效应曲线.

  5. Measurements of 60Co in spoons activated by neutrons during the JCO criticality accident at Tokai-mura in 1999.

    Science.gov (United States)

    Gasparro, J; Hult, M; Komura, K; Arnold, D; Holmes, L; Johnston, P N; Laubenstein, M; Neumaier, S; Reyss, J-L; Schillebeeckx, P; Tagziria, H; Van Britsom, G; Vasselli, R

    2004-01-01

    Neutron activated items from the vicinity of the place where the JCO criticality accident occurred have been used to determine the fluence of neutrons around the facility and in nearby residential areas. By using underground laboratories for measuring the activation products, it is possible to extend the study to also cover radionuclides with very low activities from long-lived radionuclides. The present study describes gamma-ray spectrometry measurements undertaken in a range of underground laboratories for the purpose of measuring (60)Co more than 2 years after the criticality event. The measurements show that neutron fluence determined from (60)Co activity is in agreement with previous measurements using the short-lived radionuclides (51)Cr and (59)Fe. Limits on contamination of the samples with (60)Co are evaluated and shown to not greatly affect the utility of neutron fluence determinations using (60)Co activation.

  6. The depth-dependence of the biological effectiveness of 60Co gamma rays in a large absorber determined by dicentric chromosomes in human lymphocytes.

    Science.gov (United States)

    Schmid, Ernst; Roos, Hartmut; Kramer, Hans-Michael

    2008-01-01

    Radiobiological evidence is shown concerning a significant depth-dependence of the maximum relative biological effectiveness at limiting low doses (RBE(M)) of (60)Co gamma rays in a cubic polymethylmethacrylate (PMMA) phantom of 30 cm edge length. Using the dose-response curve for the dicentric data in human lymphocytes obtained in the present experiment at a depth of 20 cm, together with the comprehensive and consistent data set determined earlier at smaller depths of the PMMA phantom, there is an increase in the RBE(M) value by a factor of 2.18 +/- 1.25 at a depth of 20 cm relative to 1 cm in the phantom. All the dicentric data are based on identical exposure durations and irradiation temperatures as well as identical culture and evaluation conditions, with blood from the same donor.

  7. CITOGENÉTICA DE TRIGO E TRITICALES IRRADIADOS COM 60Co

    Directory of Open Access Journals (Sweden)

    Núblea Teresa Felkl Manara

    1991-04-01

    Full Text Available RESUMO Foi estudado o comportamento meiótico de uma cultivar de trigo (RS1 e dois triticales (TSA1 X S - 8017 e TSA1 X Jacuí, irradiados com 60Co para detectar variabilidade quanto a fertilidade para fins de melhoramento. As dosagens de radiação utilizadas foram 35 e 37,5kr de 60Co para a cultivar de trigo e 30kr para os triticales. Foram avaliados o pareamento e a segregação dos cromossomos, bem como o índice meiótico, em células-mães dos grãos de pólen, nas gerações M1 e M3 utilizando-se o método do smear. Todos os genótipos avaliados apresentaram mais de 90% de suas células com pareamento normal. A segregação cromossômica mostrou variação entre os genótipos. O índice meiótico indicou que o trigo irradiado com menor dosagem de radiação apresentou a mais alta porcentagem de tétrades normais. A geração M3 do cruzamento TSA X Jacuí apresentou índices meióticos acima de 90%. Esses genótipos serão avaliados para características agronômicas uma vez que, do ponto de vista citogenético não apresentam problemas para o melhorista.

  8. Quality of Intensity Modulated Radiation Therapy Treatment Plans Using a {sup 60}Co Magnetic Resonance Image Guidance Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Wooten, H. Omar, E-mail: hwooten@radonc.wustl.edu; Green, Olga; Yang, Min; DeWees, Todd; Kashani, Rojano; Olsen, Jeff; Michalski, Jeff; Yang, Deshan; Tanderup, Kari; Hu, Yanle; Li, H. Harold; Mutic, Sasa

    2015-07-15

    Purpose: This work describes a commercial treatment planning system, its technical features, and its capabilities for creating {sup 60}Co intensity modulated radiation therapy (IMRT) treatment plans for a magnetic resonance image guidance radiation therapy (MR-IGRT) system. Methods and Materials: The ViewRay treatment planning system (Oakwood Village, OH) was used to create {sup 60}Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup plans using a third-party linear accelerator (linac)-based planning system were also created. Plans were evaluated by attending physicians and approved for treatment. The {sup 60}Co and linac plans were compared by evaluating conformity numbers (CN) with 100% and 95% of prescription reference doses and heterogeneity indices (HI) for planning target volumes (PTVs) and maximum, mean, and dose-volume histogram (DVH) values for OARs. Results: All {sup 60}Co IMRT plans achieved PTV coverage and OAR sparing that were similar to linac plans. PTV conformity for {sup 60}Co was within <1% and 3% of linac plans for 100% and 95% prescription reference isodoses, respectively, and heterogeneity was on average 4% greater. Comparisons of OAR mean dose showed generally better sparing with linac plans in the low-dose range <20 Gy, but comparable sparing for organs with mean doses >20 Gy. The mean doses for all {sup 60}Co plan OARs were within clinical tolerances. Conclusions: A commercial {sup 60}Co MR-IGRT device can produce highly conformal IMRT treatment plans similar in quality to linac IMRT for a variety of disease sites. Additional work is in progress to evaluate the clinical benefit of other novel features of this MR-IGRT system.

  9. 五指毛桃水提液对60Coγ射线致小鼠骨髓细胞DNA损伤的防护作用%Protective Role of Aqueous Extract from Fici Hirtae Radix for DNA Damage of Bone Marrow Cells by 60Coγ-Ray in Mice

    Institute of Scientific and Technical Information of China (English)

    王晓平; 段丽菊; 黄翔; 岑业文; 李桂芬

    2011-01-01

    目的 探讨五指毛桃水提液对60Coγ射线所致的小鼠骨髓细胞DNA损伤的防护作用.方法 40只SPF级♂小鼠随机分为5组:阴性对照组给予生理盐水,辐射模型组单纯接受照射,3个五指毛桃剂量组分别给予相当于生药5,10,20 g.kg-1.d-1五指毛桃水提液,连续灌胃7d.除阴性对照组外,所有小鼠接受全身一次性60Coγ射线照射,照射剂量为6Gy.照射24 h后处死小鼠,取股骨,制作骨髓单细胞悬液,用单细胞凝胶电泳实验检测小鼠骨髓细胞DNA损伤情况.结果 辐射模型组小鼠骨髓细胞DNA的尾部DNA百分率(Tail DNA%)和尾矩(Tail Moment)高于阴性对照组(P<0.01),五指毛桃各剂量组的 Tail DNA%和Tail Moment均显著低于辐射模型组(P<0.01),且随着给药剂量的增加,Tail DNA%和Tail Moment降低.结论 五指毛桃水提液对60Coγ射线损伤小鼠骨髓细胞DNA具有一定的防护作用.%OBJECTIVE To investigate the protective role of aqueous extract from Fici Hirtae Radix for bone marrow cells DNA of 60Coγ-ray irradiated mice. METHODS Forty SPF male mice were randomized into 5 groups. Negative control group was given normal saline, irradiated group was radiation model group and 3 Fici Hirtae Radix dose groups were orally given aqueous extracts from Fici Hirtae Radix of 5, 10, 20 g·kg-1·d-1 for 7 consecutive days. Except the negative control group, all mice received 6 Gy irradiation of whole body. After 24 h of irradiation, mice were sacrificed on femur. Single cell suspension was produced. DNA damage was detected using single cell gel electrophoresis experiment. RESULTS The results showed that Tail DNA% and Tail Moment of radiation model mice were higher than negative control group (P<0.01). Tail DNA% and Tail Moment of all Fici Hirtae Radix dose groups were significantly lower than radiation model group(P<0.01). As the dose increased,Tail DNA% and Tail Moment reduced. CONCLUSION Aqueous extracts from Fici Hirtae Radix have

  10. {sup 137}Cs, {sup 60}Co and {sup 40}K uptake by lettuce plants in two distributions of soil contamination

    Energy Technology Data Exchange (ETDEWEB)

    Quinto, Francesca [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, via Vivaldi 43, 81100 Caserta (Italy); CIRCE, INNOVA, via Campi Flegrei 34, Pozzuoli 80078 (Italy)], E-mail: francesca.quinto@unina2.it; Sabbarese, Carlo; Visciano, Lidianna; Terrasi, Filippo; D' Onofrio, Antonio [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, via Vivaldi 43, 81100 Caserta (Italy); CIRCE, INNOVA, via Campi Flegrei 34, Pozzuoli 80078 (Italy)

    2009-08-15

    {sup 137}Cs and {sup 60}Co, two of the radionuclides more representative of discharges from nuclear facilities, are of interest for radiological protections because of their great mobility in biosphere and affinity with biological systems. The aim of the present work is the investigation of the possible influence of the vertical distribution of {sup 137}Cs and {sup 60}Co in soil upon their uptake by lettuce as function of plant's growth. An experiment ad hoc has been carried out in field conditions. The results show that (i) the transfer of {sup 137}Cs and {sup 60}Co from soil to lettuce is independent by their distribution in soil, (ii) the soil-plant transfer factors of {sup 137}Cs and {sup 60}Co show a similar trend vs. growth stage, (iii) the {sup 40}K transfer factor trend is different from those of anthropogenic radionuclides, and (iv) {sup 137}Cs and {sup 60}Co specific activities are about 1 Bq/kg, in the mature vegetable with soil activity from 9 to 21 kBq/m{sup 2}.

  11. Preliminary Study on the Quantitative Value Transfer Method of Absorbed Dose to Water in 60Co γ Radiation

    Directory of Open Access Journals (Sweden)

    SONG Ming-zhe

    2015-01-01

    Full Text Available Absorbed dose to water in 60Co γ radiation is the basic physics quantity in the quantitative value system of radiation therapy, it is very necessary for radiation therapy. The study on the quantitative value transfer method of absorbed dose to water in 60Co γ Radiation could provide important technical support to the establishment of Chinese absorbed dose to water quantity system. Based on PTW-30013 ionization chamber, PMMA water phantom and 3D mobile platform, quantitative value transfer standard instrument was established, combined with the requirement of IAEA-TRS398, developed preliminary study of 60Co absorbed dose to water quantity value transfer method. After the quantity value transfer, the expanded uncertainty of absorbed dose to water calibration factor of PTW-30013 was 0.90% (k=2, the expanded uncertainty of absorbed dose to water of 60Co γ reference radiation in Radiation Metrology Center (SSDL of IAEA was 1.4% (k=2. The results showed that, this value transfer method can reduce the uncertainty of 60Co absorbed dose to water effectively in Secondary Standard Dosimetry Laboratory.

  12. Dynamic observation of polypide in semen and blood of rabbits infected with Toxoplasma tachyzoites

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Toxoplasma gondii (T. gondii) is one of the intracellular parasitized protozoa and may cause severe medical complications in fetus or immunocompromised individuals. T. gondii existed as tachyzoite during acute stage while as bradyzoite during chronic phase in human cells. To improve understanding of the prevention, diagnosis, and treatment of the disease, it is important to explore the distribution and fluctuation and other biological features of T. gondii in host. The trophozoite had been found in the saliva, blood or urine of the host.1-4 Some studies suggested the dynamic changes of circulating antibody and toxoplasma circulating antigen (TCA) either in blood or in urine.5,6 T. gondii in tissue or blood cannot be counted exactly under the microscope because it was only several micrometers in size and thus most of the studies were performed qualitatively by mouse inoculation or immunology methods. The quantitative fluorescent polymerase chain reaction (QF-PCR) and its application raised the possibility for dynamic observation of the polypide in the host.7,8 In this study, blood and semen were collected from the male rabbit model infected with toxoplasma tachyzoites and T. gondii was detected by QF-PCR quantitatively.

  13. Real-Time Telemetric Monitoring in Whole-Body 60Co Gamma-Photon Irradiated Rhesus Macaques (Macaca mulatta)

    Science.gov (United States)

    2010-01-01

    anemia , and thrombocytopenia could occur. Moistened biscuits with fruit juice, fluids, and/or colloids would be provided. During days 14–25, the...logical features. In: The Laboratory Nonhuman Pri- mate. Boca Raton, FL: CRC Press, 2002. 11 Haigh MV, Paterson E: Effects of a single session of

  14. Quality of Intensity Modulated Radiation Therapy Treatment Plans Using a (60)Co Magnetic Resonance Image Guidance Radiation Therapy System

    DEFF Research Database (Denmark)

    Wooten, H Omar; Green, Olga; Yang, Min

    2015-01-01

    PURPOSE: This work describes a commercial treatment planning system, its technical features, and its capabilities for creating (60)Co intensity modulated radiation therapy (IMRT) treatment plans for a magnetic resonance image guidance radiation therapy (MR-IGRT) system. METHODS AND MATERIALS......: The ViewRay treatment planning system (Oakwood Village, OH) was used to create (60)Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup......% prescription reference isodoses, respectively, and heterogeneity was on average 4% greater. Comparisons of OAR mean dose showed generally better sparing with linac plans in the low-dose range organs with mean doses >20 Gy. The mean doses for all (60)Co plan OARs were within...

  15. Soil to plant transfer of {sup 137}Cs and {sup 60}Co in Ferralsol, Nitisol and Acrisol

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, M.A. [Instituto de Radioprotecao e Dosimetria, CNEN, Av. Salvador Allende s/no, Recreio, CEP: 22780-160, Rio de Janeiro, RJ (Brazil)], E-mail: angelica@ird.gov.br; Bartoly, F.; Viana, A.G.; Silva, M.M.; Rochedo, E.R.R. [Instituto de Radioprotecao e Dosimetria, CNEN, Av. Salvador Allende s/no, Recreio, CEP: 22780-160, Rio de Janeiro, RJ (Brazil); Perez, D.V. [Centro Nacional de Pesquisa de Solos, EMBRAPA, R. Jardim Botanico 1024, CEP: 22460-000, Rio de Janeiro, RJ (Brazil); Conti, C.C. [Instituto de Radioprotecao e Dosimetria, CNEN, Av. Salvador Allende s/no, Recreio, CEP: 22780-160, Rio de Janeiro, RJ (Brazil)

    2008-03-15

    In this study, soil to plant transfer factor values were determined for {sup 137}Cs and {sup 60}Co in radish (Raphanus sativus), maize (Zea mays L.) and cabbage (Brassica oleracea L. var. capitata) growing in gibbsite-, kaolinite- and iron-oxide-rich soils. After 3 years of experiment in lysimeters it was possible to identify the main soil properties able to modify the soil to plant transfer processes, e.g. exchangeable K and pH, for {sup 137}Cs, and organic matter for {sup 60}Co. Results of sequential chemical extraction were coherent with root uptake and allowed the recognition of the role of iron oxides on {sup 137}Cs behaviour and of Mn oxides on {sup 60}Co behaviour. This information should provide support for adequate choices of countermeasures to be applied on tropical soils in case of accident or for remediation purposes.

  16. 100 Gy 60Co γ-Ray Induced Novel Mutations in Tetraploid Wheat

    Directory of Open Access Journals (Sweden)

    Chuntao Yang

    2014-01-01

    Full Text Available 10 accessions of tetraploid wheat were radiated with 100 Gy 60Co γ-ray. The germination energy, germination rate, special characters (secondary tillering, stalk with wax powder, and dwarf, meiotic process, and high-molecular-weight glutenin subunits (HMW-GSs were observed. Different species has different radiation sensibility. With 1 seed germinated (5%, T. dicoccum (PI434999 is the most sensitive to this dose of radiation. With a seed germination rate of 35% and 40%, this dose also affected T. polonicum (As304 and T. carthlicum (As293. Two mutant dwarf plants, T. turgidum (As2255 253-10 and T. polonicum (As302 224-14, were detected. Abnormal chromosome pairings were observed in pollen mother cells of both T. dicoccoides (As835 237-9 and T. dicoccoides (As838 239-8 with HMW-GS 1Ax silent in seeds from them. Compared with the unirradiated seed of T. polonicum (As304 CK, a novel HMW-GS was detected in seed of T. polonicum (As304 230-7 and its electrophoretic mobility was between 1By8 and 1Dy12 which were the HMW-GSs of Chinese Spring. These mutant materials would be resources for wheat breeding.

  17. The Behaviour of 134Cs, 60Co, and 85Sr Radionuclides in Marine Environmental Sediment

    Directory of Open Access Journals (Sweden)

    Nariman H.M. Kamel

    2002-01-01

    Full Text Available This work describes experimental investigations and modelling studies on the sorption of radionuclides 134Cs, 60Co, and 85Sr by certain marine sediments within Egypt. The chemical composition of the marine sediments was determined. The soluble salts were measured for the sediments and the concentrations of the released cations, Al3+, Fe3+, and Si4+, were measured for the sediment materials in 0.1 M NaClO4 aqueous solution at different hydrogen ion concentrations. The two main factors that control the uptake of the radionuclides onto the sediment are the pH and the exchangeable capacities of the sediment materials. Surface complex model was used to estimate the surface charge densities and the electric surface potential of the marine sediment materials. These two parameters were calculated at the surface capacity sites of the sediment materials. The desorption of the adsorbed cations was determined by means of selective consecutive extraction tests using different chemical reagents including (1 1 M MgCl2 (pH 7, (2 1 M ammonium oxalate (pH 3-5, (3 0.04 M NH2OH,HCl in 25% acetic acid (pH 3-4, (4 H2O2 in 5% HNO3(pH 2-3, and (5 digestion with nitric acid followed by hydrofluoric and perchloric acids (pH 2.

  18. Evaluation of the ionizing radiation effects of the {sup 60}Co on the physical, chemical and nutritional properties of Phaseolus vulgaris L. e Vigna unguiculata (L.) Walp beans; Avaliacao dos efeitos da radiacao ionizante de {sup 60}Co em propriedades fisicas, quimicas e nutricionais dos feijoes Phaseolus vulgaris L. e Vigna unguiculata (L.) Walp

    Energy Technology Data Exchange (ETDEWEB)

    Villavicencio, Anna Lucia Casanas Haasis

    1998-07-01

    The effects of {sup 60} Co ionizing radiations in doses of 0; 0.5; 1.5; 2.5; 5.0 and 10 kGy on beans, Phaseolus vulgaris L., of the carioca variety and Vigna unguiculata (L.) Walp, of the macacar variety stored for 6 months were studied. The cooking time was established, and then the following analyses were carried out: Sensory, vitamins B{sub 1}, B{sub 2} and B{sub 6} protein content, biological evaluation in rats (Food intake and Weight gain (in grams)), apparent Digestibility (Dapp), apparent Net Protein Utilization (NPUapp) and apparent Biological Value (BVapp), as well as the applicability of detection methods of irradiated foodstuffs through germination tests, the analysis of DNA migration, thermoluminescence and analysis of the carbohydrates formed by radiation. Changes in the cooking time were observed for all doses. In doses up to 1 kGy, the nutritional quality of the irradiated beans were not altered. The application of the proposed detection methods of the irradiated foodstuffs allowed the detection of irradiated beans with doses as low as 0.5 kGy. (author)

  19. Uptake and release of [sup 54]Mn and [sup 60]Co in Fucus vesiculosus L. and its epiphytes

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, L. (Lund Univ. (Sweden). Dept. of Marine Ecology)

    1994-01-01

    Fucus vesiculosus L. with epiphytic Pilayella littoralis (L.) Kjelm, Enteromorpha intestinalis (L.) Link and Cladophora sp, was collected at a swedish locality where contamination by [sup 54]Mn and [sup 60]Co was relatively low and then transplanted to a locality in the vicinity of the Barsebaeck nuclear power plant in the Oeresund, Southern Sweden. The reverse process was also carried out. Differences in uptake and release of [sup 54]Mn and [sup 60]Co were studied in the various species and in tissues of different ages. (Author).

  20. Study on the energy dependence of gamma radiation detectors for {sup 137}Cs and {sup 60}Co; Estudo da dependencia energetica de detectores de radiacao gama para {sup 137}Cs e {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Nonato, Fernanda B.C.; Diniz, Raphael E.; Carvalho, Valdir S.; Vivolo, Vitor; Caldas, Linda V.E., E-mail: fbnonato@ipen.b, E-mail: rediniz@ipen.b, E-mail: vcsouza@ipen.b, E-mail: vivolo@ipen.b, E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    38 Geiger-Mueller radiation detectors and 9 ionization chambers were calibrated, viewing to study the energy dependence of the monitor response for gamma radiation fields ({sup 137}Cs and {sup 60}Co). The results were considered satisfactory only for ionization chambers and for some Geiger-Mueller detectors

  1. Multi-membrane-bound structures of Apicomplexa: II. the ovoid mitochondrial cytoplasmic (OMC) complex of Toxoplasma gondii tachyzoites.

    Science.gov (United States)

    Köhler, Sabine

    2006-03-01

    Apicomplexa including the causative agents of toxoplasmosis and malaria reportedly possess one or few tubular-shaped mitochondria that permeate, more or less branched, throughout these unicellular parasites. Electron micrographs generated herein from serial-sectioned Toxoplasma gondii tachyzoites demonstrated, however, a greater diversity regarding both the shape of the cultured parasite's single mitochondrion and its sub-structural organization. Moreover, a unique subcellular construction was detected that basically comprised a pouch-shaped subdivision of the tachyzoite mitochondrion plus a fraction of parasitic cytoplasm enclosed therein. This composite assembling, termed ovoid mitochondrial cytoplasmic (OMC) complex, characteristically displayed a highly reduced matrix lumen of its mitochondrial border construction, which furthermore often failed to possess any cristae or contained tightly pleated cristae, thus creating a pouch-shaped multi-laminar wall of four or more membranous layers, respectively. Given this architecture, cross-sectioned OMC complexes of T. gondii tachyzoites frequently mimicked in size and shape the parasites' plastid-like organelle (apicoplast). Moreover, like the apicoplast, the OMC complex was often found adjacent to the tachyzoite's single Golgi complex and constantly located in close proximity to the outer membrane of the parasite's nuclear envelope. The T. gondii OMC complex differed, however, from the apicoplast in its exact fine structural organization and a stage-restricted presence that was apparently linked to mitochondrial growth and/or division. Any special function(s) possibly performed by the T. gondii OMC complex remains, nevertheless, to be elucidated.

  2. The effect of 60Co-gamma radio-sterilization on Boswellia carterii essential oil composition

    Directory of Open Access Journals (Sweden)

    P. Badr

    2016-10-01

    Full Text Available Background and objectives:Gamma-irradiation is used vastly for both decontamination and sterilization of natural products; but these high-energy rays can affect heat-sensitive essential oils. Methods: The oleo-gum-resin of Boswellia carterii (Burseraceae was sterilized by γ-irradiation at dose 30 KGy. The essential oils obtained by hydrodistillation of non-irradiated Boswellia (NIB and irradiated Boswellia (IB were analyzed by GC/MS and the changes were compared. The structure of octyl acetate as the major component and marker of B. carterii was confirmed by MS/MS. Results: Twenty-five compounds comprising 99.55% of NIB oil and nineteen compounds comprising 98.61% of IB oil were identified. Major constituents which were common for both oils were octyl acetate (52.67 % in NIB, 76.51 % in IB, 1-octanol (6.37 % in NIB, 5.19 % in IB, duva-4, 8, 13-triene-1,3α diol (5.52 % in NIB, 3.94 % in IB, verticiol (13.63 % in NIB and verticillane type diterpene (5.4 % in IB they made up 78.19% and 91.04% of NIB and IB, respectively. Conclusion: Gamma irradiation was an efficient method for sterilization of Boswellia carterii oleo-gum resin, but it resulted in change in the essential oil composition particularly octyl acetate changed from 52.67% to 76.51%.

  3. A 60Co multipurpose radiation processing facility at Bahia Blanca, Argentina

    Science.gov (United States)

    Curzio, O. A.; Croci, C. A.

    The aim of the project is to have a multipurpose facility which will enable us to show the techno-economic viability of the irradiation process applied to regional products, important from the economic point of view. The topics will fundamentally be connected with regional themes such as food preservation and the modification of polymer structures. This project will make it possible to carry out basic and applied studies related to radiation chemistry, dosimetry and engineering irradiation processes. The facility will operate in the Universidad Nacional del Sur (UNS) with a maximum activity of 18.5 PBq of Co-60. The viability and design of the irradiation facility is supported by the Government of the Buenos Aires Province since it is interested in the socio-economic benefit of this technology at the regional level.

  4. Immobilization of 60Co and 90Sr ions using red mud from aluminum industry

    Directory of Open Access Journals (Sweden)

    Milenković Aleksandra S.

    2014-01-01

    Full Text Available The removal of 60Co and 90Sr from the aqueous phase was tested using red mud - the fine grained residue from bauxite ore processing. This industrial waste represents a mixture of numerous minerals, mainly oxides and hydroxides of Fe, Al, Si, and Ti. Experiments were conducted as a function of contact time, pH, and pollutant concentrations. Kinetic data were well fitted with a pseudo-second order equation. The calculated rate constants and initial sorption rates indicated faster sorption of Sr2+ ions. Removal of both cations rapidly increased with the initial pH increase from 2.5 to 3.5. With the further increase of pH, Co2+ sorption was nearly constant (98%-100%, whereas Sr2+ removal remained at the same level to initial pH ~8 and gradually increased to 100% at pH 12. Equilibrium sorption data followed the Langmuir model, with the maximum sorption capacities of 0.52 mmol/g for Co2+ and 0.31 mmol/g for Sr2+. Sorbed cations exhibited high stability in distilled water. Desorption of Co2+ was also negligible in the presence of the competing Ca2+ cation, while 42%-25% of Sr2+ ions were desorbed depending on the previously sorbed amount. The results indicate that red mud is of potential significance as Co2+ and Sr2+ immobilization agent due to its high efficiency, abundance, and low-cost. [Projekat Ministarstva nauke Republike Srbije, br. 43009

  5. On-line {sup 60}Co monitor for reactor recirculation system piping in primary containment vessel during reactor operation

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Katsunori, E-mail: katsunori.ueno.pa@hitachi.com [Hitachi Research Laboratory, Hitachi, Ltd., Hitachi 319-1224, Ibaraki (Japan); Tadokoro, Takahiro [Hitachi Research Laboratory, Hitachi, Ltd., Hitachi 319-1224, Ibaraki (Japan); Tsuyuki, Mizuho; Matsubara, Hirofumi; Ota, Nobuyuki; Nagase, Makoto [Hitachi-GE Nuclear Energy, Ltd., Hitachi 317-0073, Ibaraki (Japan)

    2014-10-15

    Highlights: • We developed an on-line {sup 60}Co monitor for reactor recirculation system piping during reactor operation. • Energy resolution at 1.4 × 10{sup 6} cps is 33 keV at 1332 keV using a pulse integral method. • A coincidence method is applied to reduce an effect of background gamma rays. • The coincidence counting of {sup 60}Co cascade gamma rays could be detected for a background dose rate of 4.8 mSv/h. - Abstract: Water chemistry control during reactor operation and installation of temporary radiation shielding prior to scheduled outages are carried out in order to reduce workers’ dose exposure caused by {sup 60}Co which is the main radiation source during scheduled outages of boiling water reactor (BWR) power plants. It is necessary to monitor the deposited {sup 60}Co on inner surfaces of reactor recirculation system (RRS) piping to evaluate effects of water chemistry control. We have developed an on-line {sup 60}Co monitor (OLCM) for this purpose. The OLCM applies a pulse integral method as a new method to measure gamma-ray counts of more than 1.0 × 10{sup 6} counts per second (cps) and a coincidence counting method to reduce an effect of background gamma rays caused by {sup 16}N in the measurement of {sup 60}Co cascade gamma rays. Energy resolution at 1.4 × 10{sup 6} cps is 33 keV using the pulse integral method and single LaBr{sub 3}:Ce scintillation detector. The energy resolutions of this detector using the fast response photo multiplier tube (PMT) are 50 keV at 1.5 × 10{sup 6} cps and 59 keV at 2.1 × 10{sup 6} cps. Furthermore, we measured the energy spectra using the pulse integral method, the coincidence counting method and two LaBr{sub 3}:Ce scintillation detectors and examined the transition of coincidence counting for {sup 60}Co detection under high dose rate during reactor operation at the Kyoto University Research Reactor (KUR). The coincidence counting of {sup 60}Co cascade gamma rays could be detected, and the result was

  6. Composition dependence of magnetic and magnetotransport properties in C60-Co granular thin films

    Science.gov (United States)

    Sugai, Isamu; Sakai, Seiji; Matsumoto, Yoshihiro; Naramoto, Hiroshi; Mitani, Seiji; Takanashi, Koki; Maeda, Yoshihito

    2010-09-01

    Composition dependence of magnetic and magnetotransport properties in C60Cox thin films exhibiting large magnetoresistance (MR) effect was investigated in the Co composition range of x =8-20, where x denotes the number of Co atoms per C60 molecule. From the superparamagnetic magnetization curves observed, the average diameter (dave) of Co nanoparticles dispersed in the matrix phase was evaluated to be approximately 1 nm for the sample of x =8, and increased with the Co composition, x. By analyzing the temperature (T) dependence of resistivity based on the model by Abeles et al. [Adv. Phys. 24, 407 (1975)], the average charging energies (⟨ÊC⟩) of Co nanoparticles were evaluated to be 2-9 meV for the samples of x =8-17 while the considerably weak temperature dependence suggested much smaller values of ⟨ÊC⟩ for the samples of x >17. The composition dependence of dave and ⟨ÊC⟩ revealed a structural transition from well-defined granular structures in the range of x =8-17 to magnetically and electronically coupled states of Co nanoparticles over x ˜17. As a result of the structural change, the MR behavior became different between the two composition regions separated at x ˜17. In particular, for the samples of x =8-17, the bias-voltage (V) dependence of the MR ratio in the low-V region fits well with an unusual exponential form of MR=MR0 exp(-V/Vc) at T proportion to ⟨ÊC⟩ and also that the fitting parameter Vc is closely correlated with ⟨ÊC⟩. These results indicate that the charging effect of Co nanoparticles plays an important role in the anomalously large MR effect of C60-Co granular films. In addition, the power-law dependence of MR on T (MR∝T-α,α˜2) was also observed at relatively high temperature range T ≥10 K in the wide range of the composition.

  7. The 1997 determination of the Australian standards of exposure and absorbed dose at {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Huntley, R.B.; Boas, J.F. [Australian Radiation Laboratory, Yallambie, VIC (Australia); Van der Gaast, H. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1998-05-01

    The arrangements for the maintenance of the Australian standards for {sup 60}Co are described in detail. The primary standards are a graphite cavity chamber for exposure/air kerma and a graphite calorimeter for absorbed dose. These secondary standards are described and their responses in corresponding {sup 90}Sr reference sources are reported. Accurate ratios between the Australian Radiation Laboratory (ARL) and Australian Nuclear Science and Technology (ANSTO) {sup 90}Sr reference sources are derived for use in future calibrations. The value of 28.8 years for the half-life of {sup 90}Sr is confirmed. The usefulness of {sup 90}Sr reference source measurements in quality assurance is discussed. The charge sensitivity and linearity of the ANSTO electrometers are reported by two different methods and are compared with previous results. Calibration factors for all the secondary standard ionization chambers are given, in terms of exposure, air kerma and absorbed dose to water. Calibration factors are also given for most of the chambers in terms of absorbed dose to graphite. The methods of deriving the calibration factors are explained in detail, including all the corrections applied to both the primary and secondary standard measurements. Three alternative methods of deriving the absorbed dose to water calibration factors are compared. The reported calibration factors are compared with previous results. Changes in the Australian units of exposure, air kerma and absorbed dose to graphite and water are derived from changes in the corresponding calibration factors. The Australian units of exposure and air kerma have not changed significantly since 1990. The Australian unit of absorbed dose to graphite is now 1.1 % smaller than in 1993 and 1.3 % smaller than in 1990. The Australian unit of absorbed dose to water is now 1.4 % smaller than in 1993, but is only 0.9 % smaller than in 1990. Comparisons of the Australian standards of exposure/air kerma and absorbed dose with

  8. Radiosensibilidad de semillas de soya a los rayos gamma 60Co

    Directory of Open Access Journals (Sweden)

    C. de la Fé

    2000-01-01

    Full Text Available El presente estudio se desarrolló en las instalaciones del Instituto Nacional de Ciencias Agrícolas, con el objetivo de evaluar la radiosensibilidad de semillas de soya a los rayos gamma 60Co. Para su ejecución, se seleccionaron e irradiaron muestras de 50 semillas de la variedad Cubasoy-23, las que fueron sembradas en condiciones semicontroladas (macetas en la campaña de primavera, 1997. Las dosis de radiación fueron desde los 50 hasta los 480 Gy, con incrementos de 50 Gy entre las dosis de 50 y 200 Gy e incrementos de 40 Gy entre esta última y la dosis de 480 Gy. Las evaluaciones realizadas consistieron en porcentaje de semillas germinadas a los tres, seis y nueve días de la siembra, altura de las plantas a los 10, 20 y 50 días y número de pares de hojas emitidas a los 10 y 20 días de la siembra. El estudio realizado evidenció la ocurrencia de un efecto fuerte de las dosis aplicadas en el porcentaje de semillas germinadas, resultando las dosis próximas a los 280 Gy las de mayor efecto radioestimulador de la germinación. Desde el punto de vista de la altura de las plantas, el efecto de las dosis aplicadas se correspondió con el descrito para otros materiales biológicos irradiados, caracterizándose este por un aumento a dosis bajas seguido por una reducción cada vez mayor a medida que las dosis aplicadas se incrementaron. Por su parte, la emisión de hojas por las plantas mantuvo un comportamiento en correspondencia con la altura de las plantas. Los resultados del estudio permiten sugerir la aplicación de dosis próximas a los 360 Gy en los trabajos dirigidos a la creación de variabilidad genética en programas de mejora por inducción de mutaciones

  9. Sorption of {sup 60}Co and {sup 137}Cs in sediments at Piraquara de Fora, Angra dos Reis, RJ, Brazil; Sorcao de {sup 60}Co e {sup 137}Cs em sedimentos do Saco de Piraquara de Fora - Angra dos Reis

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Franciane M.; Martins, Nadia S.F.; Lauria, Dejanira D., E-mail: francian@ird.gov.br, E-mail: nadia@ird.gov.br, E-mail: dejanira@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Ferreira, Ingryd M., E-mail: ingrydmarques@hotmail.com [Instituto Federal do Rio de Janeiro (IFRJ), RJ (Brazil); Azevedo, Izabella M.A.P., E-mail: izabella_azevedo@id.uff.br [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2013-07-01

    In this study, sediment of Piraquara de Fora, located near the launch area of the effluents of the Central Nuclear Almirante Alvaro Alberto - CNAAA Nuclear Power Plants, were collected. It were determined the parameters particle size and cationic exchange capacity (CTC). From the sorption curves of {sup 60}Co and {sup 137}Cs, obtained experimentally in the laboratory, were estimated preliminary values of Kd at equilibrium, for these radionuclides in order of magnitude of 10{sup 2}.

  10. Neospora caninum tachyzoites inoculated by the conjunctival route are not vertically transmitted in pregnant cattle: a descriptive study.

    Science.gov (United States)

    Moore, D P; Alvarez-García, G; Chiapparrone, M L; Regidor-Cerrillo, J; Lischinsky, L H; de Yaniz, M G; Odeón, A C; Ortega-Mora, L M; Campero, C M

    2014-01-17

    The aim of this study was to evaluate whether Neospora caninum tachyzoites (Nc-1) inoculated by the conjunctival route in pregnant cows were able to generate infection in their fetuses. Group 1 contained 2 naturally infected cows; group 2 contained two cows inoculated intravenously with 2.5 × 10(8) tachyzoites, group 3 contained two cows inoculated with 2.5 × 10(8) tachyzoites by the conjunctival route, and group 4 contained two uninfected control cows. The four inoculated cows from groups 2 and 3 were challenged at 23 weeks of gestation. An indirect fluorescent antibody test (IFAT), recombinant NcGRA7-based ELISA, ELISA for IgG subisotypes and Western blot analysis were assessed to characterize the humoral immune response in dams. Sera from their fetuses were tested also using Western blot analysis. Routine microscopic evaluation of H&E stained fetal tissues was made and any fetal tissues and placentas with lesions compatible with Neospora-infection were processed by immunohistochemistry (IHC). DNA extraction from fresh and formalin-fixed, paraffin-embedded fetal tissues were tested by nested PCR. All dams from groups 1, 2 and 3 were seropositive by IFAT, rNcGRA7-based-ELISA and Western blot. IgG1/IgG2 ratios were ≤ 1 at weeks 27 and 29 of gestation. Only fetuses from groups 1 and 2 developed N. caninum specific antibodies by Western blot. Histopathological lesions compatible with those caused by N. caninum were observed in fetuses from groups 1 and 2. N. caninum cysts and tachyzoites were observed by IHC on fetal tissues from groups 1 and 2. Only fetal samples from group 2 were positive by PCR. Further work is needed not only to characterize the cellular immune response but also to clarify the consequences on the dam after conjunctival inoculation of N. caninum tachyzoites. This study shows that N. caninum tachyzoites inoculated by the conjunctival route were not vertically transmitted in pregnant cows.

  11. In contrast to Toxoplasma gondii, Neospora caninum tachyzoites did not sustain multiplication in vitro at increased incubation temperatures.

    Science.gov (United States)

    Rezende-Gondim, Mariana M; da Silva, Aristeu V; Schares, Gereon; Gondim, Luís F P

    2017-01-30

    Neospora caninum and Toxoplasma gondii are coccidian parasites that infect a wide range of mammalian and avian species. While viable T. gondii has been in vitro isolated in natural infections from wild and domestic birds, attempts to isolate N. caninum from naturally-infected birds were unsuccessful. We speculate that body temperatures of birds, which are usually higher than those of mammals, may impair the multiplication of N. caninum. In contrast to N. caninum, T. gondii can grow in vitro at temperatures higher than 37°C. To test the hypothesis that N. caninum tachyzoites are impaired to grow in vitro at high temperatures, three strains of N. caninum (NC-1, NC-Liverpool, and NC-Bahia) and three of T. gondii (RH, ME-49 and NED) were cultivated at gradually increasing temperatures starting at 37°C up to 41.5°C. A permanent chicken cell line was chosen for the study. Parasites were observed microscopically and their presence in culture was evaluated by species-specific conventional PCRs. In a second experiment, growth rates of T. gondii (RH strain) and N. caninum (NC-1 strain) were evaluated after direct passage of tachyzoites from 37°C to 41.5°C, and quantified by real-time PCR. In addition to comparisons between N. caninum and T. gondii, growth rates of three T. gondii strains were compared at high temperatures. Neospora caninum tachyzoites could not sustain multiplication at temperatures between 39°C and 41.5°C. Toxoplasma gondii tachyzoites continued to multiply at the same experimental conditions. Direct passage of N. caninum tachyzoites from 37°C to 41.5°C caused a significant decrease in the number of parasites during 96h of observation, while T. gondii had a significant increase in the number of stages after the same period of time. T. gondii RH strain (clonal type I) presented a different growth rate at 41.5°C when compared with type II and type III strains. In conclusion, multiplication of N. caninum tachyzoites in vitro was inhibited at

  12. Effects of {sup 60}Co gamma-rays, ultraviolet light, and mitomycin C on halobacterium salinarium and thiobacillus intermedius

    Energy Technology Data Exchange (ETDEWEB)

    Shahmohammadi, H.R.; Asgarani, E.; Terato, Hiroaki; Ide, Hiroshi; Yamamoto, Osamu [Hiroshima Univ. (Japan)

    1997-03-01

    Lethal effects of {sup 60}Co {gamma}-rays, UV light, and mitomycin C on two kinds of bacteria, Halobacterium salinarium which grows in highly concentrated salt media and Thiobacillus intermedius which requires reduced sulfur compounds, were studied and compared with those on Escherichia coli B/r. D{sub 37} values for H. salinarium, T. intermedius and E. coli B/r were 393, 150, and 92 Gy, respectively, by exposure to {sup 60}Co {gamma}-rays. They were 212, 38, and 10 J/m{sup 2}, respectively, by exposure to UV light and 2.36, 0.25, and 0.53 {mu}g/ml/h, respectively, by exposure to mitomycin C. Against these agents, H salinarium was much more resistant than T. intermedius and E. coli B/r. (author)

  13. Effects of 60Co gamma-rays, ultraviolet light, and mitomycin C on Halobacterium salinarium and Thiobacillus intermedius.

    Science.gov (United States)

    Shahmohammadi, H R; Asgarani, E; Terato, H; Ide, H; Yamamoto, O

    1997-03-01

    Lethal effects of 60Co gamma-rays, UV light, and mitomycin C on two kinds of bacteria, Halobacterium salinarium which grows in highly concentrated salt media and Thiobacillus intermedius which requires reduced sulfur compounds, were studied and compared with those on Escherichia coli B/r. D37 values for H. salinarium, T. intermedius and E. coli B/r were 393, 150, and 92 Gy, respectively, by exposure to 60Co gamma-rays. They were 212, 38, and 10 J/m2, respectively, by exposure to UV light and 2.36, 0.25, and 0.53 microgram/ml/h, respectively, by exposure to mitomycin C. Against these agents, H. salinarium was much more resistant than T. intermedius and E. coli B/r.

  14. Investigation of the /sup 59/Co(n,. gamma. )/sup 60/Co reaction with unpolarized and polarized neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Kopecky, J. (Stichting Energieonderzoek Centrum Nederland, Petten. Nuclear Structure Group); Delfini, M.G. (Stichting Energieonderzoek Centrum Nederland, Petten. Nuclear Structure Group; Rijksuniversiteit Utrecht (Netherlands). Fysisch Lab.); Chrien, R.E. (Brookhaven National Lab., Upton, NY (USA))

    1984-10-15

    Capture of 24 keV neutrons and polarized as well as unpolarized thermal neutrons in /sup 59/Co has been investigated. Of the 350 ..gamma..-rays observed 335 could be placed in a /sup 60/Co level scheme containing 144 levels. The reaction Q-value amounts to 7491.92(8) keV. The chi/sup 2/ analysis of the circularly polarized ..gamma..-rays results in 31 unambiguous spin assignments for /sup 60/Co levels. The fraction of the J=4/sup -/ channel in the thermal capture was determined to be (80 +- 1)%. An average ..gamma..-ray multiplicity of 2.3 gammas per neutron capture was observed. The resulting level scheme is compared to shell-model predictions. Possible reaction mechanisms are discussed.

  15. Leaching of 60Co and 137Cs from spent ion exchange resins in cement–bentonite clay matrix

    Indian Academy of Sciences (India)

    I B Plecas; R S Pavlovic; S D Pavlovic

    2003-12-01

    The leaching rate of 60Co and 137Cs from the spent cation exchange resins in cement–bentonite matrix has been studied. The solidification matrix was a standard Portland cement mixed with 290–350 (kg/m3) spent cation exchange resins, with or without 2–5% of bentonite clay. The leaching rates from the cement–bentonite matrix for 60Co: (4,2–7,0) × 10-5 (cm/d) and 137Cs: (3,2–6,6) × 10-4 (cm/d), after 125 days were measured. From the leaching data the apparent diffusivity of cobalt and cesium in cement–bentonite clay matrix with a waste load of 290–350 (kg/m3) spent cation exchange resins, was measured for 60Co: (1,1–4,0) × 10-6 (cm2/d) and 137Cs: (0,5–2,6) × 10-4 (cm2/d), after 125 days. The results presented in this paper are part of the results obtained in a 20-year mortar and concrete testing project which will influence the design of radioactive waste management for a future Serbian radioactive waste disposal centre.

  16. Neospora caninum tachyzoite immunome study reveals differences among three biologically different isolates.

    Science.gov (United States)

    Regidor-Cerrillo, Javier; García-Lunar, Paula; Pastor-Fernández, Iván; Álvarez-García, Gema; Collantes-Fernández, Esther; Gómez-Bautista, Mercedes; Ortega-Mora, Luis M

    2015-09-15

    Pathogenesis of bovine neosporosis is determined by different host- and parasite-dependent factors, including isolate virulence. A previous study identified that several Neospora caninum tachyzoite proteins were more abundant in virulent isolates, Nc-Liv and Nc-Spain7, compared with the low-virulent isolate Nc-Spain1H. Herein, we explored differences in the immunomes of these three isolates. Protein extracts from the Nc-Liv, Nc-Spain1H and Nc-Spain7 isolates were analysed in a 3×3 design by 2-DE immunoblot using sera from experimentally infected mice with these same three isolates. All isolates displayed a highly similar antigenic pattern when they were assessed using the same serum. Most of the reactive spots were located in the acidic region (pH 3-7) and grouped in 3 antigenic areas (250-70, 45-37 and 35-15 KDa). Differences found in the immunome depended on the sera used, regardless of the extract employed. In this sense, sera from Nc-Liv and Nc-Spain7 infected mice recognized the highest number of antigens, followed by Nc-Spain1H infected mice sera. In fact, 4 proteins identified by MS were not consistently detected in each isolate extract by sera from low-virulent Nc-Spain1H-infected mice: serine-threonine phosphatase 2C and superoxide dismutase (related to metabolism), gliding associated protein GAP45 (related to tachyzoites invasion), and NcGRA1 (located on dense granules). Similarly, 4 non-identified spots and another 2 spots chains located in 45-37 kDa area were not detected by this pooled sera. Variations between virulent Nc-Spain7 and Nc-Liv were limited to the absence of recognition by sera from Nc-Spain7-infected mice of GAP45 and the spot chains located in the 45-37 kDa area. These results suggest that variations in the immunome profiles rely on the immune response induced by each isolate and that these differentially recognized antigens could be investigated as putative virulence markers of neosporosis.

  17. Biochemical detection of E-ADA on Neospora caninum tachyzoites and the effects of a specific enzymatic inhibitor

    Directory of Open Access Journals (Sweden)

    Alexandre A. Tonin

    2015-01-01

    Full Text Available Objective. This study aimed to investigate the presence and activity of the ecto adenosine deaminase (E-ADA enzyme in tachyzoites of Neospora caninum (Nc-1 strain, as well as to assess the activity of a well-known E-ADA inhibitor, the deoxycoformycin. Materials and methods. The parasites were grown in cell culture, being subsequently separated in a pellet of tachyzoites, on which the E-ADA activity was tested using the concentrations 0 (control, 0.2, 0.4 and 0.8 mg mL-1. Results. The E-ADA showed high activity, progressively increasing its activity according to the enhancement of the protein concentration. The test was carried out with different concentrations of deoxycoformycin, showing that it was able to inhibit the E-ADA present on the free form of the parasite. Conclusions. Based on these results we conclude that the E-ADA is present on tachyzoites of N. caninum, and deoxycoformycin is able to inhibit this enzyme. In this sense, knowing the negative impact of N. caninum on reproductive issue in cattle (mainly abortion, might it is an alternative in order to deal with this parasitic infection.

  18. Change of urine metabolites spectra and its correlation with time in rats exposed to single 60Co γ-rays%单次60Co γ射线照射致大鼠尿液代谢谱变化及其时间相关性

    Institute of Scientific and Technical Information of China (English)

    张慧芳; 杨彪; 郭月凤; 邢利虹; 郭万龙; 党旭红

    2011-01-01

    OBJECTIVE: To investigate effects of urinary metabolites from single exposure to 5' radiation and to screen urinary metabolites related close to 5' radiation damage in rats. METHODS: 15 male adult SD rats were exposed to 60Co γ -rays whole body once at 6.0 Gy, 0.7 Gy/min. Urine was collected from rats one day before irradiation and 1 d, 2 d, 3 d, 4 d, 8 d, 18 d, 30 d and 45 d after irradiation. Urine 1H NMR spectra were acquired, principal component analysis (PCA) and partial least-squares-discriminant analysis (PLS-DA) methods are utilized to analyze 1H NMR spectra data. Then we looked for the metabolites that contributed more in the difference between urine 1H NMR spectra before exposure and every time after expos ure(abbreviateed as common difference metabolites) and analyzed relation between the change of their relative contents and post-irradiation time. RESULTS: 60Co γ irradiation could cause visible change of urine IH NMR spectra. Common difference metabolites were taurine, trimethylamine-N-oxide, praline, ereatinine, citrate, sueeinate, acetate and lactate that coutributed more in change of 1H NMR spectra of urine collected at different times after exposure. For 1-45 d after exposure, the relative contents of proline and taurine were markedly higher than before irradiation, and citrate and suceinate were lower. However, the relative contents of trimethylamine-N-oxide, acetate and lactate first increased 1 d after irradiation and then decreased for 2-45 d after irradiation. CONCLUSION : The disorder of metabolism in rats induced by high-dose γ radiation did not completely recover for 45 days after irradiation, that showed persistent changes of the relative contents of urine taurine, proline, creatinine, citrate, succinate, acetate and lactate in exposed rats. Taurine and proline could become potential combined metabolic markers of acute high-dose radiation injury.%目的:探讨γ射线单次照射对大鼠尿液代谢物的影响,初步筛选与γ辐射

  19. Medulloblastoma in childhood: long-term results of treatment. [X rays; /sup 60/Co

    Energy Technology Data Exchange (ETDEWEB)

    Broadbent, V.A.; Barnes, N.D.; Wheeler, T.K.

    1981-07-01

    Thirty-one children under the age of 15 years with verified medulloblastoma were treated at Addenbrookes Hospital from 1940 to 1976. In addition to surgical treatment, all received high dose irradiation to the whole neuraxis. Nine were still alive in 1979, of whom eight were examined. All these patients showed some residual problems, but five were leading active lives and had only minor physical disability. There was evidence of disturbance in growth in all the children. Growth hormone secretion in response to exercise was, however, normal in five of six patients tested. Frank mental retardation was present in three children. A raised resing TSH level was found in two children, one of whom had a multinodular goiter. Long-term follow-up of children who survive medulloblastoma is clearly necessary and consideration should perhaps be given to revision of current treatment regimes in very young children.

  20. 中国实验快堆生产同位素60Co的优化设计研究%Optimization Design Research for 60 Co Production in CEFR

    Institute of Scientific and Technical Information of China (English)

    杨佳音; 杨勇; 张强; 王事喜; 吴明宇

    2015-01-01

    中国实验快堆(CEFR)是我国建设的第一座金属钠冷却快中子反应堆 ,其特点是比功率高、中子注量率高.由于CEFR能谱硬、中子泄漏多 ,本工作对利用这部分泄漏中子在快堆反射层生产60 Co同位素进行了可行性研究 ,并通过引入慢化剂设计适合的几何结构、选择合理的辐照位置和辐照时间等一系列措施对同位素生产进行优化 ,以提高60 Co比活度.优化中采用MCNP和ORIGEN2程序作为计算软件.计算结果表明 ,通过优化设计 ,60 Co比活度有显著提高 ,说明利用快堆反射层的泄漏中子生产60 Co是可行的.%As the first sodium coolant fast reactor in China ,CEFR has the characteris-tics such as high power rating ,high neutron flux and high neutron leakage as its hard spectrum .These leakage neutrons can be used to produce radioisotope 60 Co in reflecting layer region by means of some special optimization designs ,including introducing mod-erator ,choosing appropriately geometrical structure design ,reasonable irradiation loca-tion and irradiation cycle length ,to improve specific activity of 60Co .The codes MCNP and ORIGEN2 were used to perform the calculations .The higher specific activity of 60 Co can be obtained by these optimization designs ,so it is feasible to produce 60 Co utili-zing these leakage neutrons in reflecting layer region of CEFR .

  1. Cloning and Clone Analysis of GRA1 Gene from Local Isolate Toxoplasma gondii Tachyzoite

    Directory of Open Access Journals (Sweden)

    Didik T Subekti

    2008-03-01

    Full Text Available The GRA1 gene of Toxoplasma gondii encoding protein called GRA1 protein. GRA1 protein known to be immunogenic and essentialy involved in modification of parasitophorus vacoule which has role in immune evasion and virulency of organism. The local isolate of T. gondii is successfuly isolated and known as highly pathogenic isolate similarly as its RH strain. Unfortunately, the homology sequence of GRA1 gene between those isolate still unknown. The purpose of the research are to clone the GRA1 gene and to analyze the homology from pathogenic T. gondii isolate and RH strain. Tachyzoite of T. gondii was grown in mice peritoneum by intraperitoneal injection. Then, total mRNA was isolated and purified. cDNA was synthesized from mRNA and then amplified using F1 dan R1 primers to get clone of GRA1 from local isolate. Homology analysis was perform using several bioinformatic softwares. The result showed that cDNA of GRA1 from local isolate has 84% homologs with RH strain of T.gondii. However, when subsequently editing performed to parts of suspected non coding sequence of cDNA GRA1 to get CDS of GRA1, the homology was increase to 100% compare to CDS of GRA1 of RH strain.

  2. Molecular characterization of Toxoplasma gondii formin 3, an actin nucleator dispensable for tachyzoite growth and motility.

    Science.gov (United States)

    Daher, Wassim; Klages, Natacha; Carlier, Marie-France; Soldati-Favre, Dominique

    2012-03-01

    Toxoplasma gondii belongs to the phylum Apicomplexa, a group of obligate intracellular parasites that rely on gliding motility to enter host cells. Drugs interfering with the actin cytoskeleton block parasite motility, host cell invasion, and egress from infected cells. Myosin A, profilin, formin 1, formin 2, and actin-depolymerizing factor have all been implicated in parasite motility, yet little is known regarding the importance of actin polymerization and other myosins for the remaining steps of the parasite lytic cycle. Here we establish that T. gondii formin 3 (TgFRM3), a newly described formin homology 2 domain (FH2)-containing protein, binds to Toxoplasma actin and nucleates rabbit actin assembly in vitro. TgFRM3 expressed as a transgene exhibits a patchy localization at several distinct structures within the parasite. Disruption of the TgFRM3 gene by double homologous recombination in a ku80-ko strain reveals no vital function for tachyzoite propagation in vitro, which is consistent with its weak level of expression in this life stage. Conditional stabilization of truncated forms of TgFRM3 suggests that different regions of the molecule contribute to distinct localizations. Moreover, expression of TgFRM3 lacking the C-terminal domain severely affects parasite growth and replication. This work provides a first insight into how this specialized formin, restricted to the group of coccidia, completes its actin-nucleating activity.

  3. Macrophages facilitate the excystation and differentiation of Toxoplasma gondii sporozoites into tachyzoites following oocyst internalisation

    Science.gov (United States)

    Freppel, Wesley; Puech, Pierre-Henri; Ferguson, David J. P.; Azas, Nadine; Dubey, Jitender P.; Dumètre, Aurélien

    2016-01-01

    Toxoplasma gondii is a common parasite of humans and animals, which is transmitted via oocysts in cat faeces or tissue cysts in contaminated meat. The robust oocyst and sporocyst walls protect the infective sporozoites from deleterious external attacks including disinfectants. Upon oocyst acquisition, these walls lose their integrity to let the sporozoites excyst and invade host cells following a process that remains poorly understood. Given the resistance of the oocyst wall to digestive enzymes and the ability of oocysts to cause parenteral infections, the present study investigated the possible contribution of macrophages in supporting sporozoite excystation following oocyst internalisation. By using single cell micromanipulations, real-time and time-point imaging techniques, we demonstrated that RAW macrophages could interact rapidly with oocysts and engulfed them by remodelling of their actin cytoskeleton. Internalised oocysts were associated to macrophage acidic compartments and showed evidences of wall disruption. Sporozoites were observed in macrophages containing oocyst remnants or in new macrophages, giving rise to dividing tachyzoites. All together, these results highlight an unexpected role of phagocytic cells in processing T. gondii oocysts, in line with non-classical routes of infection, and open new perspectives to identify chemical factors that lead to oocyst wall disruption under physiological conditions. PMID:27641141

  4. Comparison of an ELISA assay for the detection of adhesive/invasive Neospora caninum tachyzoites

    Directory of Open Access Journals (Sweden)

    Luiz Miguel Pereira

    Full Text Available Neospora caninum belongs to the phylum Apicomplexa, the causative agent of neosporosis, which leads to economic impacts on cattle production. A common feature among apicomplexan parasites is the invasive process driven mostly by the parasite. As a first evaluation of candidate molecules that play a possible role by interfering in this invasive process, the in vitro invasion assay is a fast and direct way to screen future agonists or antagonists. This work involved the development of a new cell culture ELISA and transient β-galactosidase activity applied to the semi-quantitative detection of N. caninum in Vero cell culture. Cell culture ELISA is based on histochemistry and immunology, resulting in a colorimetric reaction. The β-galactosidase activity was obtained by the transient transfection of the lacZ gene under control of RPS13 promoter of N. caninum. These methods were used to evaluate the effects of temperature (37°C and 85°C on the invasion and adhesion of tachyzoites. The three tested methods (real time PCR, β-galactosidase activity and ELISA showed a similar pattern, indicating that different methods may be complementary.

  5. Comparison of an ELISA assay for the detection of adhesive/invasive Neospora caninum tachyzoites.

    Science.gov (United States)

    Pereira, Luiz Miguel; Yatsuda, Ana Patrícia

    2014-03-01

    Neospora caninum belongs to the phylum Apicomplexa, the causative agent of neosporosis, which leads to economic impacts on cattle production. A common feature among apicomplexan parasites is the invasive process driven mostly by the parasite. As a first evaluation of candidate molecules that play a possible role by interfering in this invasive process, the in vitro invasion assay is a fast and direct way to screen future agonists or antagonists. This work involved the development of a new cell culture ELISA and transient β-galactosidase activity applied to the semi-quantitative detection of N. caninum in Vero cell culture. Cell culture ELISA is based on histochemistry and immunology, resulting in a colorimetric reaction. The β-galactosidase activity was obtained by the transient transfection of the lacZ gene under control of RPS13 promoter of N. caninum. These methods were used to evaluate the effects of temperature (37°C and 85°C) on the invasion and adhesion of tachyzoites. The three tested methods (real time PCR, β-galactosidase activity and ELISA) showed a similar pattern, indicating that different methods may be complementary.

  6. Study about the sensibility in vitro of different strains of Vibrio cholera 01 exposed to 60 Co gamma radiation; Estudo da sensibilidade in vitro de diferentes cepas de Vibio cholerae 01 a radiacao gama de 60Co

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Ivany Rodrigues de [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Servicos de Saude; Gelli, Dilma Scala; Jakabi, Miyoko [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Secao de Microbiologia; Mastro, Nelida Lucia del [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: nlmastro@net.ipen.br

    1998-07-01

    The presence of some microorganisms in food, or the metabolites originated during their own multiplication may bring several diseases to humans: intoxications and food borne infections. Among the agents that may cause those diseases, we find Vibrio cholerae 01. In this experiment, the studies are focused on the radiosensibility in vitro of four strains of V. cholerae 01, exposed to different doses of ionizing radiation of {sup 60} Co. The results are compared with other data related to bacterial food borne diseases, including water. (author)

  7. SPRF60Coγ圃装置研制%THE ESTABLISHMENT OF SPRF COBALT-60 GAMMA FIELD

    Institute of Scientific and Technical Information of China (English)

    王家银; 张运法; 李品芳

    1984-01-01

    SPRF60Coγ圃装置由二阶围墙、帽形伞塔.半地下水井三者良好组合成为一个半封闭型γ圃.既可降低墙外散射剂量,又能在圃内达到引变剂量.对解决城郊建圃中存在的防护剂量与引变剂量关键技术问题有重要意义.

  8. Gamma irradiation effects in W films

    Energy Technology Data Exchange (ETDEWEB)

    Claro, Luiz H. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil) and Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei (Brazil); Santos, Ingrid A. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil); Silva, Cassia F. [Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei, SP (Brazil)

    2013-05-06

    Using the van Der Pauw methodology, the surface resistivity of irradiated tungsten films deposited on Silicon substrate was measured. The films were exposed to {gamma} radiation using a isotopic {sup 60}Co source in three irradiation stages attaining 40.35 kGy in total dose. The obtained results for superficial resistivity display a time annealing features and their values are proportional to the total dose.

  9. Influence of 60Co gamma radiation on fluorine plasma treated enhancement-mode highelectron-mobility transistor

    Institute of Scientific and Technical Information of China (English)

    Quan Si; Hao Yue; Ma Xiao-Hua; Yu Hui-You

    2011-01-01

    AlGaN/GaN depletion-mode high-electron-mobility transistor (D-HEMT) and fluorine (F) plasma treated enhancement-mode high-electron-mobility transistor (E-HEMT) are exposed to 60Co gamma radiation with a dose of 1.6 Mrad (Si). No degradation is observed in the performance of D-HEMT. However, the maximum transconductance of E-HEMT is increased after radiation. The 2DEG density and the mobility are calculated from the results of capacitance-voltage measurement. The electron mobility decreases after fluorine plasma treatment and recovers after radiation. Conductance measurements in a frequency range from 10 kHz to 1 MHz are used to characterize the trapping effects in the devices. A new type of trap is observed in the F plasma treated E-HEMT compared with the D-HEMT, but the density of the trap decreases by radiation. Fitting of Gp/ω data yields the trap densities DT = (1 - 3) × 1012 cm-2-·eV-1 and DT = (0.2 - 0.8) × 1012 cm-2·eV-1 before and after radiation, respectively.The time constant is 0.5 ms-6 ms. With F plasma treatment, the trap is introduced by etch damage and degrades the electronic mobility. After 60Co gamma radiation, the etch damage decreases and the electron mobility is improved. The gamma radiation can recover the etch damage caused by F plasma treatment.

  10. The effects of exposure of {sup 60}Co on the oxidant/antioxidant status among radiation victims

    Energy Technology Data Exchange (ETDEWEB)

    Demir, Mustafa E-mail: mmdemir@e-kolay.net; Konukoglu, Dildar; Kabasakal, Levent; Yelke, Hakan Kadir; Ergen, Kadir; Ahmed, Sabbir

    2002-07-01

    This retrospective study has been performed with radiation victims who were accidentally exposed to a {sup 60}Co source and its release into the environment. The aim of the study was to assess the effects of elevated radiation exposures on plasma level, on erythrocyte thio barbituric acid reactive substance (TBARS) level and on erythrocyte glutathione (GSH) levels. Patients were treated in different hospitals with different symptoms such as nausea, vomiting, dizziness, along with severe anemia in some patients. Blood samples were collected 3-5 days following the radiation accident. Increases in plasma (6.25{+-}0.90 nmol ml{sup -1}) and erythrocyte TBARS levels (330.5{+-}30.5 {mu}mol gHb{sup -1}) were found in comparison to a healthy group (3.72{+-}0.68 nmol ml{sup -1} and 150.7{+-}20.5 {mu}mol gHb{sup -1}, respectively) at a significant level (p<0.001). Erythrocyte GSH levels (5.2{+-}0.30 {mu}mol gHb{sup -1}) were found to be decreased among the victims (healthy group: 10.2{+-}0.7 {mu}mol gHb{sup -1}) at the same significance level (p<0.001). These observations confirm a significant change induced by radiation in the oxidant/antioxidant status among the victims. It is suggested here that antioxidant supplementation therapy might be effective in preventing the harmful effects of {sup 60}Co radiation among radiation victims.

  11. Laboratory studies of the diffusive transport of {sup 137}Cs and {sup 60}Co through potential waste repository soils

    Energy Technology Data Exchange (ETDEWEB)

    Itakura, Takashi [Australian Nuclear Science and Technology Organisation, Menai, NSW (Australia); Airey, David W., E-mail: david.airey@sydney.edu.a [School of Civil Engineering, University of Sydney, Sydney, NSW 2006 (Australia); Leo, Chin Jian [School of Engineering and Industrial Design, University of Western Sydney, Penrith, NSW (Australia); Payne, Timothy; McOrist, Gordon D. [Australian Nuclear Science and Technology Organisation, Menai, NSW (Australia)

    2010-09-15

    Tests using reconstituted samples have been performed to assess the diffusive transport of {sup 137}Cs and {sup 60}Co through natural regolith materials from a region in South Australia being considered for a radioactive waste repository. A double diffusion cell apparatus made of polycarbonate resin was developed to estimate the effective diffusion (D{sub e}) and sorption coefficients (K{sub d}) that allowed large withdrawals from the source and collector cells and has enabled tests with low concentrations of radioactivity. An alternative to porous stainless steel filter plates has also been used to reduce uncertainty in test interpretation. Analysis of the transient data used a staged method of the Laplace transform to take into consideration the volume of the samples withdrawn from the apparatus during testing. At test completion samples were cut into slices and analysed for radionuclide concentration. Data obtained from the sliced samples confirmed that both numerical and experimental data produced acceptable mass balance. The D{sub e} values obtained in this study were of the order of 10{sup -6} cm{sup 2} s{sup -1} for both species, higher than previously published data. The K{sub d} values from the diffusion and batch sorption tests were in reasonable agreement for {sup 137}Cs, but an order of magnitude different for {sup 60}Co. The sorption of the latter radionuclide was strongly pH dependent, and this dependency during diffusion tests would benefit from further investigation.

  12. Development and characterization of a graphite-walled ionization chamber as a reference dosimeter for 60Co beams

    Science.gov (United States)

    Perini, Ana P.; Neves, Lucio P.; Caldas, Linda V. E.

    2014-11-01

    A graphite-walled ionization chamber with a sensitive volume of 6.4 cm3 was developed at the Calibration Laboratory of IPEN (LCI) to determine the air kerma rate of a 60Co source. This new prototype was developed to be a simple chamber, without significant nongraphite components and with a simple set-up, which allows the determination of its various required correction factors by Monte Carlo simulations. This new ionization chamber was characterized according to the IEC 60731 standard, and all results were obtained within its limits. Furthermore, Monte Carlo simulations were undertaken to obtain the correction factors involved with the air kerma determination. The air kerma rate obtained with the graphite-walled ionization chamber was compared with that from the reference dosimeter at the LCI, a PTW ionization chamber (model TN30002). The results obtained showed good agreement within the statistical uncertainties. A graphite ionization chamber was assembled and characterized as a reference dosimeter. The characterization test results were within recommended limits. Monte Carlo simulations were undertaken to obtain the correction factors. The air kerma rate of a 60Co source was obtained with satisfactory results.

  13. Multiple superficial basal cell carcinomas (basalomatosis) following cobalt irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, A.; Przybilla, B. [Muenchen Univ. (Germany). Dermatologische Klinik und Poliklinik; Peter, R.U. [Federal Armed Forces Medical Academy, Munich (Germany). Inst. of Radiobiology

    1995-10-01

    Basalomatosis is an uncommon skin condition characterized by the occurrence of multiple basal cell carcinomas. Many cases reported in the literature have been attributed to arsenic treatment in psoriasis patients. We report a patient with basalomatosis caused by cobalt-60 ({sup 60}Co) irradiation. A 55-year-old farmer developed 43 basal cell carcinomas 20 years after treatment of an immuno-blastoma with {sup 60}Co irradiation. All the tumours were located within the radiation fields. Other possible causes of basalomatosis, such as arsenic intoxication and basal cell naevus syndrome, were excluded. The patient`s multiple superficial basal cell carcinomas probably represent a late adverse effect of the {sup 60}Co irradiation. (Author).

  14. Toxoplasma gondii Cyclic AMP-Dependent Protein Kinase Subunit 3 Is Involved in the Switch from Tachyzoite to Bradyzoite Development

    Directory of Open Access Journals (Sweden)

    Tatsuki Sugi

    2016-05-01

    Full Text Available Toxoplasma gondii is an obligate intracellular apicomplexan parasite that infects warm-blooded vertebrates, including humans. Asexual reproduction in T. gondii allows it to switch between the rapidly replicating tachyzoite and quiescent bradyzoite life cycle stages. A transient cyclic AMP (cAMP pulse promotes bradyzoite differentiation, whereas a prolonged elevation of cAMP inhibits this process. We investigated the mechanism(s by which differential modulation of cAMP exerts a bidirectional effect on parasite differentiation. There are three protein kinase A (PKA catalytic subunits (TgPKAc1 to -3 expressed in T. gondii. Unlike TgPKAc1 and TgPKAc2, which are conserved in the phylum Apicomplexa, TgPKAc3 appears evolutionarily divergent and specific to coccidian parasites. TgPKAc1 and TgPKAc2 are distributed in the cytomembranes, whereas TgPKAc3 resides in the cytosol. TgPKAc3 was genetically ablated in a type II cyst-forming strain of T. gondii (PruΔku80Δhxgprt and in a type I strain (RHΔku80Δhxgprt, which typically does not form cysts. The Δpkac3 mutant exhibited slower growth than the parental and complemented strains, which correlated with a higher basal rate of tachyzoite-to-bradyzoite differentiation. 3-Isobutyl-1-methylxanthine (IBMX treatment, which elevates cAMP levels, maintained wild-type parasites as tachyzoites under bradyzoite induction culture conditions (pH 8.2/low CO2, whereas the Δpkac3 mutant failed to respond to the treatment. This suggests that TgPKAc3 is the factor responsible for the cAMP-dependent tachyzoite maintenance. In addition, the Δpkac3 mutant had a defect in the production of brain cysts in vivo, suggesting that a substrate of TgPKAc3 is probably involved in the persistence of this parasite in the intermediate host animals.

  15. Fluorescence in situ hybridization detection of chromosome translocations induced by 60Co γ-rays in human lymphocytes dose-response curve and persistence%用荧光原位杂交技术建立60Coγ射线诱发人外周血淋巴细胞染色体易位率剂量效应曲线及易位的持续性研究

    Institute of Scientific and Technical Information of China (English)

    王晓琳; 李进; 王知权

    2001-01-01

    Objective To study dose-response relationship for chromosome translocation and its persistence measured in human lymphocytes exposed to 60Co γ-rays.Methods The chromosome translocations in human peripheral lymphocytes were detected by fluorescence in situ hybridization using 4# and 7# combination of composite whole chromosome-specific DNA probes and Giemsa stain.Results The dose-response relationship for chromosome translocation induced by 60Co γ-rays in vitro could be described by the function:Y=0.0030+0.0134D+0.0165D2.The frequencies of chromosome translocations induced by 0.5 and 2 Gy γ-irradiation did not diminish over time,so it exhibited excellent persistence.Conclusions The results indicate that retrospective dose-reconstruction can be accomplished using chromosome translocation frequency.%目的研究不同剂量60Coγ射线诱发人外周血淋巴细胞染色体易位率和辐射剂量间的剂量效应关系以及观察易位率在同一剂量、不同时相点的变化。方法采用荧光原位杂交技术和连续Giemsa法,用4号和7号全染色体探针分析0、0.25、0.5、0.75、1和2 Gy 60Coγ射线离体照射诱发人外周血淋巴细胞染色体易位率,同时对两个剂量点进行52和72 h培养,比较其易位率。结果易位率和辐射剂量间的量效关系可以用一个二次多项式方程Y=0.0030+0.0134D+0.0165D2来描述;易位率在52和72 h培养时差异无显著性。结论易位率和辐射剂量间存在良好的量效关系,可作为进行早先照射剂量重建的理论依据。

  16. Gamma ({sup 60}CO) radiation effects on arcelin protein and evaluation of bean lineages against Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boh.) (Col.: Bruchidae);Efeito da radiacao gama ({sup 60}CO) sobre a proteina arcelina e avaliacao de linhagens de feijoeiro a Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boh.) (Col.: Bruchidae)

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, Ana Claudia Girardo

    2006-07-01

    The resistance of arcelin carrying seeds of bean lineages (Phaseolus vulgaris L.) against the bean weevils Acanthoscelides obtectus (Say, 1831) and Zabrotes subfasciatus (Bohemann, 1833) (Coleoptera: Bruchidae), and the influence of gamma radiation ({sup 60}CO) on the manifestation of arcelin resistance to Z. subfasciatus were verified. Laboratorial tests, in choice and non-choice tests, with wild specimens carrying Arc-1, Arc-2, Arc-3, Arc-4, Raz-56 and Raz-59 (with Arc-5 alleles) and commercial lineages as control IAC - Carioca and IAC - Arua were conducted. Statistical design was completely randomized, with five repetitions, with 10 g of grains from each lineage samples by portion. Attractiveness, oviposition, emergence, mortality, adults' weigh and longevity, developing period, sexual rate, seeds' weigh loss, infestation and fecundity (Z. subfasciatus) were observed. Gamma radiation doses irradiations, in general, haven't affected the resistance manifestation of lineages carrying arcelin protein variants against the Z. subfasciatus bean weevil, thus, joint application use of both control methods can be recommended. Raz-56 lineage showed high resistance of the antibiosis types and non-preference for oviposition and feeding to Z. subfasciatus, while Raz-59 showed antibiosis and non-preference for feeding, and both (Raz-56 and Raz-59) showed intermediate resistance to A. obtectus, against which lineage Arc-2 was the most harmful to its development, expressing non-preference to feeding and/or antibiosis. (author)

  17. Cloning and Sequencing cDNA Encoding for Rhoptry-2 Toxoplasma Gondii Tachyzoite Local Isolate

    Directory of Open Access Journals (Sweden)

    Wayan T. Artama

    2015-10-01

    Full Text Available Rhoptry protein belongs to an excretory and secretory antigens (ESAs that play an important role during activepenetration of parasite into the cell target. This protein an able Toxoplasma gondii to actively penetrate targetedcell, meanwhile ESAs protein stimulates intracellular vacuole modification. It is, therefore, after the parasitesuccessfully enter the cell target then Granule (GRA proteins are responsible for the formation of parasitophorusvacuole, which is protect the fusion with other intracellular compartments such as lysosomal vacuole. Consequently,this parasite is being able to survive and multiply at the cell target. The current study was aimed to clone andsequens cDNA encoding for ROP-2 of local isolated T. gondii tachizoite through DNA recombinant technique.Total ribonucleic acid (RNA was isolated from tachyzoites of local isolated T. gondii that were grown up in Balb/c mice. Messenger RNA was isolated from total RNA using PolyAtract mRNA Isolation System. Messenger RNA wasused as a template for synthesis cDNA using Riboclone cDNA Synthesis System AMV-RT. EcoRI adaptor fromRiboclone EcoRI Adaptor Ligation System was added to Complementary DNA and than ligated to pUC19. Recombinantplasmid was transformed into E. coli (XL1-Blue. The transformed E. coli XL-1 Blue were plated on LB agarcontaining X-Gal, IPTG and ampicillin. Recombinant clones (white colony were picked up and grown up in theLB medium at 37oC overnight. Expression of recombinant protein was analysed by immunoblotting in order toidentify cDNA recombinant wich is express ESA of T. gondii local isolate. Recombinant plasmid were isolatedusing alkalilysis method and were elektroforated in 1% agarose gel. The isolated DNA recombinant plasmid wascut using Eco RI and then sequenced through Big Dye Terminator Mix AB1 377A Sequencer using M13 Forward andM13 Reverse primers. The conclusion of this results showed that the recombinant clone was coding for excretoryand secretory

  18. Cloning and Sequencing cDNA Encoding for Rhoptry-2 Toxoplasma Gondii Tachyzoite Local Isolate

    Directory of Open Access Journals (Sweden)

    Murwantoko M

    2015-11-01

    Full Text Available Rhoptry protein belongs to an excretory and secretory antigens (ESAs that play an important role during active penetration of parasite into the cell target. This protein an able Toxoplasma gondii to actively penetrate targeted cell, meanwhile ESAs protein stimulates intracellular vacuole modification. It is, therefore, after the parasite successfully enter the cell target then Granule (GRA proteins are responsible for the formation of parasitophorus vacuole, which is protect the fusion with other intracellular compartments such as lysosomal vacuole. Consequently, this parasite is being able to survive and multiply at the cell target. The current study was aimed to clone and sequens cDNA encoding for ROP-2 of local isolated T. gondii tachizoite through DNA recombinant technique. Total ribonucleic acid (RNA was isolated from tachyzoites of local isolated T. gondii that were grown up in Balb/c mice. Messenger RNA was isolated from total RNA using PolyAtract mRNA Isolation System. Messenger RNA was used as a template for synthesis cDNA using Riboclone cDNA Synthesis System AMV-RT. EcoRI adaptor from Riboclone EcoRI Adaptor Ligation System was added to Complementary DNA and than ligated to pUC19. Recombinant plasmid was transformed into E. coli (XL1-Blue. The transformed E. coli XL-1 Blue were plated on LB agar containing X-Gal, IPTG and ampicillin. Recombinant clones (white colony were picked up and grown up in the LB medium at 37oC overnight. Expression of recombinant protein was analysed by immunoblotting in order to identify cDNA recombinant wich is express ESA of T. gondii local isolate. Recombinant plasmid were isolated using alkalilysis method and were elektroforated in 1% agarose gel. The isolated DNA recombinant plasmid was cut using Eco RI and then sequenced through Big Dye Terminator Mix AB1 377A Sequencer using M13 Forward and M13 Reverse primers. The conclusion of this results showed that the recombinant clone was coding for excretory

  19. Study of the action of {sup 60}Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp;Estudo da acao da radiacao gama de {sup 60}Co sobre Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris em polpa de manga congelada

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Marco Antonio dos Santos

    2009-07-01

    The application of non-thermal treatments has proven effective in inhibiting bacteria such as Salmonella and Escherichia coli. Mango is a fruit of national consumption with a great exportation potential. Meanwhile, outbreaks of foodborne disease related to mango consumption caused mistrust on the degree of food security offered by the product. The objective of this work was to establish the radioresistance of bacteria Escherichia coli, Salmonella Poona and Alicyclobacillus acidoterrestris on the mango pulp by the calculation of the D10 values and to know the radiation effect on the sensory characteristics of the fruit pulp. The microbiological profile of frozen mango pulp available at the local market was also established using conventional methods of plating and Most Probable Number (MPN). The pulps experimentally inoculated with the bacteria listed above were irradiated with doses of 0, 1, 2, 3, 4 and 5 kGy in a {sup 60}Co source. The sensory analysis was performed using a dose of 5 kGy, using the triangular test and the test of acceptance with hedonic scale. The results of this study show that the quality of mango pulp sell in the local market is not satisfactory in accordance with the standards established by the Brazilian law and the literature, showing the need of using other tools to achieve acceptable levels of quality. The D10 values obtained are in the range of 1.01 and 1.09 kGy for E. coli ATCC 8739, 0.60 and 0.98 kGy for S. poona and 0.72 and 0.88 kGy for A. acidoterrestris respectively. The triangular test showed that a 5 kGy radiation dose changed the sensory characteristics of mango pulp. Nevertheless, sensory analysis of a food product prepared with the irradiated pulp obtained good acceptance in the attributes of global appearance, flavor and aroma. (author)

  20. Study of the action of {sup 60}Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp; Estudo da acao da radiacao gama de {sup 60}Co sobre Salmonella poona, Escherichia coli e Alicyclobacillus acidoterrestris em polpa de manga congelada

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Marco Antonio dos Santos

    2009-07-01

    The application of non-thermal treatments has proven effective in inhibiting bacteria such as Salmonella and Escherichia coli. Mango is a fruit of national consumption with a great exportation potential. Meanwhile, outbreaks of food borne disease related to mango consumption caused mistrust on the degree of food security offered by the product. The objective of this work was to establish the radioresistance of bacteria Escherichia coli, Salmonella Poona and Alicyclobacillus acidoterrestris on the mango pulp by the calculation of the D10 values and to know the radiation effect on the sensory characteristics of the fruit pulp. The microbiological profile of frozen mango pulp available at the local market was also established using conventional methods of plating and Most Probable Number (MPN). The pulps experimentally inoculated with the bacteria listed above were irradiated with doses of 0, 1, 2, 3, 4 and 5kGy in a {sup 60}Co source. The sensory analysis was performed using a dose of 5 kGy, using the triangular test and the test of acceptance with hedonic scale. The results of this study show that the quality of mango pulp sell in the local market is not satisfactory in accordance with the standards established by the Brazilian law and the literature, showing the need of using other tools to achieve acceptable levels of quality. The D10 values obtained are in the range of 1.01 and 1.09kGy for E. coli ATCC 8739, 0.60 and 0.98kGy for S. poona and 0.72 e 0.88kGy for A. acidoterrestris respectively. The triangular test showed that a 5kGy radiation dose changed the sensory characteristics of mango pulp. Nevertheless, sensory analysis of a food product prepared with the irradiated pulp obtained good acceptance in the attributes of global appearance, flavor and aroma. (author)

  1. Sorption capacity studies of Scheldt sediments for /sup 60/Co, /sup 85/Sr, and /sup 137/Cs

    Energy Technology Data Exchange (ETDEWEB)

    Meeussen, M.A.; Willems, G.J.; De Ranter, C.J.

    1975-01-01

    Using /sup 60/Co, /sup 85/Sr and /sup 137/Cs as tracer ions the sorption capacity of Scheldt sediments for Co/sup 2 +/, Sr/sup 2 +/ and Cs/sup +/ was studied and their distribution coefficients between sediment and Scheldt water were determined. It is found that clay and silt samples show relatively high sorption capacities for cobalt and cesium, compared with the low fixation rate for strontium. The selectivity of the sediments for a particular ion, in competition with other ions, was studied and the sequence found is in accordance with the distribution coefficients. From these experiments it may be concluded that the high salt concentrations, present in normal Scheldt water, will limit the risks of radioactive isotopes accumulation in the sediments.

  2. A new standard cylindrical graphite-walled ionization chamber for dosimetry in 60Co beams at calibration laboratories

    Science.gov (United States)

    Neves, Lucio P.; Perini, Ana P.; Caldas, Linda V. E.

    2014-11-01

    60Co sources are used mostly at dosimetry laboratories for calibration of ionization chambers utilized for radiotherapy dosimetry, mainly in those laboratories where there is no linear accelerator available. In this work, a new cylindrical ionization chamber was developed and characterized to be used as a reference dosimeter at the Calibration Laboratory of the IPEN. The characterization tests were performed according to the IEC 60731 standard, and all tests presented results within its recommended limits. Furthermore, the correction factors for the wall, stem, central collecting electrode, nonaxial uniformity and the mass-energy absorption coefficient were determined using the EGSnrc Monte Carlo code. The air kerma rate determined with this new dosimeter was compared to the one obtained with the IPEN standard, presenting a difference of 1.5%. Therefore, the new ionization chamber prototype developed and characterized in this work presents potential use as a primary standard dosimeter at radiation metrology laboratories.

  3. Comparison of the standards for air kerma of the NRC and the BIPM for {sup 60}Co gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, C.; Allisy, P.J.; Burns, D.T. [Bureau International des Poids et Mesures (BIPM), 92 - Sevres (France); McCaffrey, J.P.; Ross, C.K. [National Research Council (Canada)

    2010-02-15

    An indirect comparison of the standards for air kerma of the National Research Council (NRC), Canada, and of the Bureau International des Poids et Mesures (BIPM) was carried out in the {sup 60}Co radiation beam of the BIPM in May 2009. The comparison result, based on the calibration coefficients for two transfer standards and expressed as a ratio of the NRC and the BIPM standards for air kerma, is 1.0032 with a combined standard uncertainty of 2.8 * 10{sup -3}. The result of the previous direct comparison in {sup 60}Cogamma rays, made in 1998 and modified in 2007 was 1.0025 (27). The degrees of equivalence between the NRC and the other participants in the key comparison have been calculated and the results are presented in the form of a matrix. A graphical presentation is also given. (authors)

  4. An investigation on the radiation sensitivity of DNA conformations to {sup 60}Co gamma rays by using Geant4 toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Semsarha, F. [Institute of Biochemistry and Biophysics (IBB), University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Goliaei, B., E-mail: goliaei@ibb.ut.ac.ir [Institute of Biochemistry and Biophysics (IBB), University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Raisali, G.; Khalafi, H. [Radiation Applications Research School, Nuclear Science and Technology Research Institute, P.O. Box 11365-3486, Tehran (Iran, Islamic Republic of); Mirzakhanian, L. [Medical Physics Unit, McGill University, 1650 Cedar Avenue, Montreal, Quebec (Canada)

    2014-03-15

    To investigate the impact of conformational properties of genetic material of living cells on radiation-induced DNA damage, single strand breaks (SSB), double strand breaks (DSB) and some microdosimetric quantities of A, B and Z-DNA conformations caused by {sup 60}Co gamma rays, have been calculated. Based on a previous B-DNA geometrical model, models of A and Z forms have been developed. Simple 34 base pairs segments of each model repeated in high number and secondary electron spectrum of {sup 60}Co gamma rays have been simulated in a volume of a typical animal cell nucleus. All simulations in this study have been performed by using the Geant4 (GEometry ANd Tracking 4)-DNA extension of the Geant4 toolkit. The results showed that, B-DNA has the lowest yield of simple strand breaks with 2.23 × 10{sup −10} Gy{sup −1} Da{sup −1} and 1.0 × 10{sup −11} Gy{sup −1} Da{sup −1} for the SSB and DSB damage yield, respectively. The A-DNA has the highest SSB yield with 3.59 × 10{sup −10} Gy{sup −1} Da{sup −1} and the Z-DNA has the highest DSB yields with 1.8 × 10{sup −11} Gy{sup −1} Da{sup −1}. It has been concluded that there is a direct correlation between the hit probability, mean specific imparted energy and SSB yield in each model of DNA. Moreover, there is a direct correlation between the DSB yield and both the mean lineal energy and topological characteristics of each model.

  5. New facility for post irradiation examination of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, Etsuo; Kawamura, Hiroshi [Oarai Research Establishment, Ibaraki-Ken (Japan)

    1995-09-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800{degrees}C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and {sup 60}Co;7.4 MBq/day.

  6. Irradiation effects on hydrases for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu E-mail: mfuruta@riast.osakafu-u.ac.jp; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio

    2000-03-01

    To apply an irradiation technique to sterilize 'Hybrid' biomedical materials including enzymes, we selected papain, a well-characterized plant endopeptidase as a model to examine durability of enzyme activity under the practical irradiation condition in which limited data were available for irradiation inactivation of enzymes. Dry powder and frozen aqueous solution of papain showed significant durability against {sup 60}Co-gamma irradiation suggesting that, the commercial irradiation sterilizing method is applicable without modification. Although irradiation of unfrozen aqueous papain solution showed an unusual change of the enzymatic activity with the increasing doses, and was totally inactivated at 15 kGy, we managed to keep the residual activity more than 50% of initial activity after 30-kGy irradiation, taking such optimum conditions as increasing enzyme concentration from 10 to 100 mg/ml and purging with N{sub 2} gas to suppress the formation of free radicals. (author)

  7. Effect of a killed whole Neospora caninum tachyzoite vaccine on the crube abortion rate of Costa Rican dairy cows under field conditions

    NARCIS (Netherlands)

    Romero, J.J.; Perez, E.; Frankena, K.

    2004-01-01

    A standard field trial was carried out to assess the effect of a commercial Neospora-vaccine based on whole killed tachyzoites (Bovilis–Neoguard, Intervet®) on the abortion rate. Eight hundred and seventy-six cows, over 2.5 months pregnant, belonging to 25 Costa Rican dairy herds, were used in the a

  8. Influence of gamma ray irradiation on metakaolin based sodium geopolymer

    Energy Technology Data Exchange (ETDEWEB)

    Lambertin, D., E-mail: david.lambertin@cea.fr [CEA, DEN, DTCD/SPDE/LP2C, F-30207 Bagnols-sur-Cèze (France); Boher, C. [CEA, DEN, DTCD/SPDE/LP2C, F-30207 Bagnols-sur-Cèze (France); Dannoux-Papin, A. [CEA, DEN, DTCD/SPDE/LCFI, F-30207 Bagnols-sur-Cèze (France); Galliez, K.; Rooses, A.; Frizon, F. [CEA, DEN, DTCD/SPDE/LP2C, F-30207 Bagnols-sur-Cèze (France)

    2013-11-15

    Effects of gamma irradiation on metakaolin based Na-geopolymer have been investigated by external irradiation. The experiments were carried out in a gamma irradiator with {sup 60}Co sources up to 1000 kGy. Various Na-geopolymer with three H{sub 2}O/Na{sub 2}O ratios have been studied in terms of hydrogen radiolytic yield. The results show that hydrogen production increases linearly with water content. Gamma irradiation effects on Na-geopolymer microstructure have been investigated with porosity measurements and X-ray pair distribution function analysis. A change of pore size distribution and a structural relaxation have been found after gamma ray irradiation.

  9. Influence of gamma ray irradiation on metakaolin based sodium geopolymer

    Science.gov (United States)

    Lambertin, D.; Boher, C.; Dannoux-Papin, A.; Galliez, K.; Rooses, A.; Frizon, F.

    2013-11-01

    Effects of gamma irradiation on metakaolin based Na-geopolymer have been investigated by external irradiation. The experiments were carried out in a gamma irradiator with 60Co sources up to 1000 kGy. Various Na-geopolymer with three H2O/Na2O ratios have been studied in terms of hydrogen radiolytic yield. The results show that hydrogen production increases linearly with water content. Gamma irradiation effects on Na-geopolymer microstructure have been investigated with porosity measurements and X-ray pair distribution function analysis. A change of pore size distribution and a structural relaxation have been found after gamma ray irradiation.

  10. Monte Carlo modeling of 60 Co HDR brachytherapy source in water and in different solid water phantom materials

    Directory of Open Access Journals (Sweden)

    Sahoo S

    2010-01-01

    Full Text Available The reference medium for brachytherapy dose measurements is water. Accuracy of dose measurements of brachytherapy sources is critically dependent on precise measurement of the source-detector distance. A solid phantom can be precisely machined and hence source-detector distances can be accurately determined. In the present study, four different solid phantom materials such as polymethylmethacrylate (PMMA, polystyrene, Solid Water, and RW1 are modeled using the Monte Carlo methods to investigate the influence of phantom material on dose rate distributions of the new model of BEBIG 60 Co brachytherapy source. The calculated dose rate constant is 1.086 ± 0.06% cGy h−1 U−1 for water, PMMA, polystyrene, Solid Water, and RW1. The investigation suggests that the phantom materials RW1 and Solid Water represent water-equivalent up to 20 cm from the source. PMMA and polystyrene are water-equivalent up to 10 cm and 15 cm from the source, respectively, as the differences in the dose data obtained in these phantom materials are not significantly different from the corresponding data obtained in liquid water phantom. At a radial distance of 20 cm from the source, polystyrene overestimates the dose by 3% and PMMA underestimates it by about 8% when compared to the corresponding data obtained in water phantom.

  11. Effect of 60Co-gamma radiation on the random walk error of interferometric fiber optic gyroscopes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Two 60Co-gamma radiation experiments were launched to explore the radiation effect on optical components and interferometric fiber optic gyroscope (IFOG). In optical components radiation experiment, the result showed that polarization-maintaining (PM) fiber coil loss was the most affected parameter in all the RWC (random walk coefficient) related parameters, compared with the weak sensitivity of other components parameters. In the IFOG radiation experiment, the RWC performance degradation was found to be almost due to an increase of the PM fiber attenuation. Based on the experiment result, a RWC prediction model in radiation, which is obtained by embedding PM fiber loss expression into the RWC model, was built following a power law of dose and dose rate. An IFOG RWC in space radiation environment was predicted from radiation dose and dose rate by the RWC prediction model. This RWC value calculated from test data is fully accorded to the RWC value predicted from radiation dose.

  12. Long-term studies of the optical components in the ZEUS calorimeter using a moving 60Co source

    Science.gov (United States)

    Bohnet, I.; Feller, R.-P.; Krumnack, N.; Möller, E.; Prause, H.; Salehi, H.; Wick, K.

    2009-02-01

    The response of the ZEUS sampling calorimeter has been studied over a period of 17 years using a moving 60Co source. The aim was to monitor the stability of the calorimeter with respect to radiation damage, ageing and mechanical damage. The measurements started in 1990 during the installation of the first calorimeter modules and ended in 2007 after the last HERA run. Within the experimental uncertainties, the longitudinal uniformity of the polymethylmethacrylate (PMMA) based wavelength shifters (Y7) did not change. There is also no evidence for radiation damage in the polystyrene (PS) based scintillators (SCSN-38) due to particle losses of the electron and proton beams. On the other hand, the investigations clearly indicate that the attenuation length of the SCSN-38 scintillators decreased continuously over the years. A comparison with data obtained from a test calorimeter showed that the same effect observed in the ZEUS calorimeter after 17 years would require a uniform exposure of all scintillators by a dose of (2.8±1) kGy of γ rays. However, it can be excluded that the degradation observed in the ZEUS calorimeter can be attributed to the radioactivity of the uranium plates of the calorimeter. Thus we expect that the decrease of the attenuation length is due to ageing of the scintillators. The ageing effects observed in SCSN-38 are compared to data taken from the literature.

  13. Influence of phantom materials on the energy dependence of LiF:Mg,Ti thermoluminescent dosimeters exposed to 20-300 kV narrow x-ray spectra, 137Cs and 60Co photons.

    Science.gov (United States)

    Massillon-J L, G; Cabrera-Santiago, A; Minniti, R; O'Brien, M; Soares, C G

    2014-08-07

    LiF:Mg,Ti, are widely used to estimate absorbed-dose received by patients during diagnostic or medical treatment. Conveniently, measurements are usually made in plastic phantoms. However, experimental conditions vary from one group to another and consequently, a lack of consensus data exists for the energy dependence of thermoluminescent (TL) response. This work investigated the energy dependence of TLD-100 TL-response and the effect of irradiating the dosimeters in different phantom materials for a broad range of energy photons in an attempt to understand the parameters that affect the discrepancies reported by various research groups. TLD-100s were exposed to 20-300 kV narrow x-ray spectra, (137)Cs and (60)Co photons. Measurements were performed in air, PMMA, wt1, polystyrene and TLDS as surrounding material. Total air-kerma values delivered were between 50 and 150 mGy for x-rays and 50 mGy for (137)Cs and (60)Co beams; each dosimeter was irradiated individually. Relative response, R, defined as the TL-response per air-kerma and relative efficiency, RE, described as the TL-response per absorbed-dose (obtained through Monte Carlo (MC) and analytically) were used to describe the TL-response. Both R and RE are normalized to the responses in a (60)Co beam. The results indicate that the use of different phantom materials affects the TL-response and this response varies with energy and material type. MC simulations reproduced qualitatively the experimental data: a) R increases, reaches a maximum at ~25 keV and decreases; b) RE decreases, down to a minimum at ~60 keV, increases to a maximum at ~150 keV and after decreases. Independent of the phantom materials, RE strongly depends on how the absorbed dose is evaluated and the discrepancies between RE evaluated analytically and by MC simulation are around 4% and 18%, dependent on the photon energy. The comparison between our results and that reported in the literature suggests that the discrepancy observed

  14. Effect of {sup 60} Co gamma radiation on trehalose level of Saccharomyces boulardii cells; Efeito da radiacao gama {sup 60} Co nos niveis de trealose de celulas de Saccharomyces boulardii

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Raquel Gouvea dos; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil). Nucleo de Radiobiologia; Duarte, Rinaldo; Nicoli, Jacques R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Microbiologia

    1996-07-01

    The medicine Floratil used for diarrhea treatment is composed by lyophilized yeast cells of Saccharomyces boulardii. The action mechanism of this product is unknown. The efficacy of S. boulardii depends on its viability. The increase in the trehalose level in S. cerevisiae cells submitted to a previous sub-lethal level heat shock results in resistance to a lethal shock. The aim of this work was to study weather the cell trehalose level is involved also in the resistance of gamma irradiation. It was noted that the yeast cells surviving to gamma irradiation had more trehalose level than control cells. Apparently there is a positive correlation between of trehalose level and gamma irradiation resistance of S.boulardii cells. (author)

  15. Thermal analysis applied to irradiated propolis

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Andrea Harumi; Machado, Luci Brocardo; Mastro, N.L. del E-mail: nelida@usp.br

    2002-03-01

    Propolis is a resinous hive product, collected by bees. Raw propolis requires a decontamination procedure and irradiation appears as a promising technique for this purpose. The valuable properties of propolis for food and pharmaceutical industries have led to increasing interest in its technological behavior. Thermal analysis is a chemical analysis that gives information about changes on heating of great importance for technological applications. Ground propolis samples were {sup 60}Co gamma irradiated with 0 and 10 kGy. Thermogravimetry curves shown a similar multi-stage decomposition pattern for both irradiated and unirradiated samples up to 600 deg. C. Similarly, through differential scanning calorimetry , a coincidence of melting point of irradiated and unirradiated samples was found. The results suggest that the irradiation process do not interfere on the thermal properties of propolis when irradiated up to 10 kGy.

  16. The effects of gamma-irradiation on some pure aroma compounds of spices.

    Science.gov (United States)

    Sjövall, O; Honkanen, E; Kallio, H; Latva-Kala, K; Sjöberg, A M

    1990-09-01

    Chemical changes due to gamma-irradiation were investigated in 11 pure aroma compounds typically found in spices. Samples were irradiated with doses of 0, 10, and 50 kGy. The irradiation source was 60Co. Irradiated samples and unirradiated controls were analyzed by gas chromatography alone and coupled with mass spectrometry. Significant changes due to the irradiation occurred only in (+/-)-linalool and alpha-terpineol, which are typical components of, for example, coriander and bay leaf. Their total amounts decreased by about 4-13% and some minor peaks increased as a result of irradiation. However, different results may be obtained when the spices themselves are irradiated.

  17. Inactivation effect of 60Co gamma ray on cysticerci of Taenia solium in pork%60Coγ射线对猪肉中囊尾蚴的辐照杀灭效应

    Institute of Scientific and Technical Information of China (English)

    钟凯; 高翔; 计融

    2011-01-01

    Objective revealing the relationship between irradiation dose and inactivation ratio for eysticerei of Taenia solium in pork, determining the minimal dose for totally killing cysticerci and providing scientific evidence for setting up relevant hygienic standards of radiation. Methods After Taenia solium infected pork being treated with different irradiation doses; cysticerci were separated and incubated in fresh swine bile. The adjusted inactivation ratio was calculated according to the survival rate. Results There was a linear correlation between irradiation dose and adjusted inactivation ratio, the D10 value was about 3.8 kGy, and a totally killing could be achieved by 4.5 kGy irradiation. Conclusion Irradiation at a dose of 4.5 kGy could be applied as the maximum dose to inactivate cysticerci of Taenia solium in pork processing.%目的 揭示猪肉中囊尾蚴灭活率与辐照剂量的相关关系及最小杀灭剂量,为制定相应辐照卫生规范提供科学依据.方法 以不同剂量Co γ射线处理感染囊尾蚴的猪肉,并用新鲜猪胆汁孵化剥离出的囊尾蚴,根据成活率计算校正灭活率.结果 辐照剂量与校正灭活率具有线性相关,D值约为3.8 kGy,4.5 kGy可完全杀灭囊尾蚴.结论 4.5 kGy γ射线对猪肉中囊尾蚴有很好的杀灭效果.

  18. Soil compaction and gamma radiation ({sup 60}Co) in the development of the cowpea beans [Vigna unguiculata, (L) Walp]; Compactacao do solo e radiacao gama ({sup 60}Co) no desenvolvimento do feijao caupi [Vigna unguiculata, (L) Walp

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Eliane Ferreira; Colaco, Waldeciro [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Radioagronomia]. E-mails: aroucha@ufpe.br; wcolaco@ufpe.br

    2005-08-15

    The objective is to investigate the effect of compaction and increased doses of gamma radiation on the development of cowpea [Vigna unguiculata, (L) Walp] var. IPA-206 cultivated in a Neossolo fluvic soil, artificially compacted. Significant differences were observed in plant height, with the increase doses in soil density (1.30 Mg.m{sup -3} - compacted soil and 1.70 Mg.m{sup -3} - non-compacted soil), and in response to increased doses of irradiation (y-rays) [ [0, 100, 200 and 300 Gy). The diameter of the stem was significantly reduced in response to the increase in soil density, however the same did not occur in relation to the doses of irradiation (y-rays) holding capacity of the soil was reduced in response to the increase in soil density. (author)

  19. APMP key comparison for the measurement of air kerma for 60Co (APMP.RI(I)-K1.1)

    Science.gov (United States)

    Webb, D. V.; Lee, J.-H.; Budiantari, C. T.; Laban, J.; Saito, N.; Srimanoroth, S.; Khaled, N. E.

    2016-01-01

    The results are reported for an APMP.R(I)-K1.1 comparison that extends the regional comparison of standards for air kerma APMP.R(I)-K1 to several laboratories unable to participate earlier. The comparison was conducted with the goal of supporting the relevant calibration and measurement capabilities (CMCs) planned for publication by the participant laboratories. The comparison was conducted by the pilot laboratory, the Australian Radiation Protection and Nuclear Safety (ARPANSA), Australia, supported by the Institute of Nuclear Energy Research (INER), Taiwan, in a modified ring-shaped arrangement from September 2009 to November 2010, in parallel with an APMP.R(I)-K4 comparison being piloted by the INER. The laboratories that took part in the comparison were the ARPANSA, the Centre of Technology of Radiation Safety and Metrology (PTKMR-BATAN), Indonesia, the Division of Radiation and Medical Devices (DMSC), Thailand, the INER, the National Centre for Radiation Science (NCRS), New Zealand, the National Institute for Standards (NIS), Egypt and the National Metrology Institute of Japan (NMIJ/AIST), Japan. The two primary laboratories, ARPANSA and NMIJ, were chosen as the linking laboratories. Three ionization chambers were used as transfer instruments to be calibrated in terms of air kerma in 60Co radiotherapy beams. The comparison result is based on the ratio between the air kerma calibration coefficients (NK) determined by the participants and the mean of the results of the linking laboratories. The mean comparison ratio was found to be within 0.5 % of the key comparison reference value KCRV. The largest deviation between any two comparison ratios for the three chambers in terms of air kerma was 2.0 %. An analysis of the participant uncertainty budgets enabled the calculation of degrees of equivalence (DoE) in terms of the deviations of the results and their associated uncertainties. As a result of this APMP comparison, the BIPM key comparison database (KCDB) should

  20. SU-E-T-380: Evaluation of BEBIG HDR 60Co System for AccuBoost Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zehtabian, M; Sina, S [Shiraz University, Shiraz, Fars (Iran, Islamic Republic of); Rivard, M [Tufts University School of Medicine, Boston, MA (United States); Meigooni, A Soleimani [Comprehensive Cancer Center of Nevada, Las Vegas, Nevada (United States)

    2015-06-15

    Purpose: In this project, the possibility of utilizing the BEBIG 60Co HDR system for AccuBoostTM treatment has been evaluated. Methods: Dose distributions in various breast sizes have been calculated for both Co-60 and Ir-192 sources using the MCNP5 code. These calculations were performed in breast tissues with thicknesses of 4cm, 6cm, and 8cm. The initial calculations were performed with the same applicator dimensions as the existing applicators used with the HDR Ir-192 system. The activity of the Co-60 source was selected such that the dose at the breast center was the same as the values from 192Ir. Then, the applicator thicknesses were increased to twice of those used with HDR Ir-192 system, for reducing skin and chest doses by Co-60 system. Dose to breast skin and chest wall were compared for both applicators types, with and without inclusion of a focusing cone at the applicator center. Results: The results showed that loading HDR Co-60 source inside the thin applicators impose higher doses to breast skin and chest wall compared to the 192Ir source. The area of the chest wall covered by 10Gy when treated by Co-60 with the thin and thick applicators, or treated by Ir-192 with thin applicator are 79cm2, 39cm2, and 3.8cm2, respectively. These values are reduced to 34cm2, 0cm2, and 0cm2 by using the focusing cone. It is worth noting that the breast skin areas covered by the 60Gy isodose line are 9.9cm2 and 7.8cm2 for Co-60 with the thin and thick applicators, respectively, while it is 20cm2 for Ir-192 when no focusing cone is present. These values are 0cm2, 0cm2, and 11cm2 in the presence of the focusing cone. Conclusion: The results indicate that using Co-60 with the thicker applicators is beneficial because of the higher half-life of Co-60, and the reduced maximum skin dose when compared with Ir-192.

  1. The influence of organic compound addition on the mobility and biological availability of the {sup 137} Cs and {sup 60} Co on tropical soils; A influencia da adicao de composto organico na mobilidade e biodisponibilidade do {sup 137} Cs e do {sup 60} Co em solos tropicais

    Energy Technology Data Exchange (ETDEWEB)

    Portilho, Antonio Passos

    2005-07-01

    The hole of manure in the mobility and bioavailability of {sup 137}Cs and {sup 60}Co in Brazilian soil was investigated. For this study an Oxisol was selected, for being the soil of larger distribution in the country, characterized by a low content in nutrients and organic substances; a Nitisol, was also selected as representative of soils with average fertility and an Organo sol, as representative of soils with high content of organic matter. These soils were transferred to an experimental area in the Instituto de Radioprotecao e Dosimetria, conditioned in plastic pots and spiked with {sup 137}Cs e {sup 60}Co. To follow the root uptake of {sup 137}Cs and {sup 60}Co we cultivated radish (Raphanus sativus, L.), in the pots receiving different doses of manure: a dose recommended for radish (2 kg/m{sup 2}); a half of the recommended dose; the double of the recommended dose and without manure addition. Only the Organo sol did not received manure. Moreover, it was investigated the potential mobility of {sup 137}Cs and {sup 60}Co associated to the unstable compounds under natural soil environment, such as the organic substance, oxides of iron etc, through the method of sequential chemical extraction. The main results show that soil to plant transfer factor (TF) for {sup 137}Cs decreases after the addition of 4 kg/m{sup 2} of manure in the Nitisol (from 0.44 to 0.06) and in the Oxisol (from 0,44 to 0,11). In relation to {sup 60}Co the TF reduced from 14,73 for 0,15 in Nitisol and from 11,25 for 0,15 to Oxisol. In the Organosols the TF values were low and comparable with values obtained in soil that received at least a dose of manure: 0,11 for {sup 137}Cs and 2,64 for {sup 60}Co. It was also observed, that the TF for {sup 137}Cs diminish with the increase of the nutrient contents (K, Ca and Mg) when manure is applied. It was verified, through the results of sequential extraction, that {sup 137}Cs was mainly associated to iron oxides in all types of studied soils. In the

  2. Fungal evaluation on green tea irradiated with different water activities

    Energy Technology Data Exchange (ETDEWEB)

    Fanaro, Gustavo B.; Duarte, Renato C.; Rodrigues, Flavio T.; Villavicencio, Anna Lucia C.H., E-mail: gbfanaro@ipen.b, E-mail: villavic@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (CTR/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes; Correa, Benedito, E-mail: correabe@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Ciencias Biologicas. Dept. de Micologia

    2011-07-01

    The aim of this study was evaluate the fungal contamination in green tea irradiated with different radiation doses and water activities. Samples were irradiated in {sup 60}Co irradiator at doses of 0, 2.5, 5.0, 7.5 and 10.0kGy with three different water activities. In the sample with decreased water activity, the count of fungi was lower than others samples followed by original Aw and the samples with the higher water activity, however there is no difference between the increased and decreased water activities samples after the irradiation on fungi contamination at dose of 2.5 kGy. (author)

  3. The Effect of 5'-Adenylic Acid on Hepatic Proteome of Mice Radiated by 60Co γ-ray

    Directory of Open Access Journals (Sweden)

    Cuilin Cheng

    2013-12-01

    Full Text Available Understanding the protection mechanism of 5'-AMP requires comprehensive knowledge of the proteins expressed during the period that the body is exposed to irradiation. Proteomics provides the tools for such analyses. Here, the experimental ICR mice were divided into three groups (normal group, model group and 5'-AMP + irradiation group. After different treatment, the hepatic total protein of each animal in three groups was separated by two-dimensional gel electrophoresis (2-DE. 2-DE analysis revealed fifty-eight protein spots were differentially expressed in comparison to three groups. From 58 protein spots, we selected nine spots to identify by MALDI-TOF-MS and received credible results. They were determined to be type I arginase, annexin A5, regucalcin, catalase, Tpm3 protein, Pdia4 protein, 14-3-3 protein epsilon, NAD-Malate dehydrogenase and heat shock protein 90. Considering the characteristic of these proteins, we proposed a possible protection pathway.

  4. Distinctions of effects of pulsed laser radiation and /sup 60/Co gamma radiation on some microorganisms. [Escherichia coli; Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Petin, V.G.; Rusina, L.K.; Sebrant, Yu.V.; Baranov, V.Yu.; Malyuta, D.D.; Niz' ev, V.G.

    1979-03-01

    Studies were made of the sensitivity of yeast cells varying in ploidy and bacterial cells varying in genotype to the effects of pulsed laser radiation and the combined effect of laser and ionizing radiation. It was demonstrated that there is no additivity of irradiation with a train of pulses, as compared to a single pulse. The impairment of cellular reproductive capacity under the influence of lasers was irreversible.

  5. Simple and Efficient Method for Measuring Anti-Toxoplasma Immunoglobulin Antibodies in Human Sera Using Complement-Mediated Lysis of Transgenic Tachyzoites Expressing β-Galactosidase

    Science.gov (United States)

    Dando, Caroline; Gabriel, Katie E.; Remington, Jack S.; Parmley, Stephen F.

    2001-01-01

    A simple and efficient method using transgenic Toxoplasma gondii tachyzoites expressing β-galactosidase was developed for detection of specific antibodies against the parasite in sera of patients. The titers obtained with the new test were similar to those obtained with the Sabin-Feldman dye test run in parallel. Although significant changes in endpoint titers were not observed when sera drawn sequentially at 2- to 3-week intervals were tested with both procedures, apparent differences in antibody affinity were observed with the new test which were not perceptible with the Sabin-Feldman dye test. Like the Sabin-Feldman dye test, the new test is based on complement lysis of tachyzoites, but it is much easier to perform and the reaction is read colorimetrically instead of visually. PMID:11376045

  6. (60)Co in cast steel matrix: A European interlaboratory comparison for the characterisation of new activity standards for calibration of gamma-ray spectrometers in metallurgy.

    Science.gov (United States)

    Tzika, Faidra; Burda, Oleksiy; Hult, Mikael; Arnold, Dirk; Marroyo, Belén Caro; Dryák, Pavel; Fazio, Aldo; Ferreux, Laurent; García-Toraño, Eduardo; Javornik, Andrej; Klemola, Seppo; Luca, Aurelian; Moser, Hannah; Nečemer, Marijan; Peyrés, Virginia; Reis, Mario; Silva, Lidia; Šolc, Jaroslav; Svec, Anton; Tyminski, Zbigniew; Vodenik, Branko; Wätjen, Uwe

    2016-08-01

    Two series of activity standards of (60)Co in cast steel matrix, developed for the calibration of gamma-ray spectrometry systems in the metallurgical sector, were characterised using a European interlaboratory comparison among twelve National Metrology Institutes and one international organisation. The first standard, consisting of 14 disc shaped samples, was cast from steel contaminated during production ("originally"), and the second, consisting of 15 similar discs, from artificially-contaminated ("spiked") steel. The reference activity concentrations of (60)Co in the cast steel standards were (1.077±0.019) Bqg(-1) on 1 January 2013 12h00 UT and (1.483±0.022) Bqg(-1) on 1 June 2013 12h00 UT, respectively.

  7. A water calorimeter for on-site absorbed dose to water calibrations in 60Co and MV-photon beams including MRI incorporated treatment equipment

    Science.gov (United States)

    de Prez, Leon; de Pooter, Jacco; Jansen, Bartel; Aalbers, Tony

    2016-07-01

    In reference dosimetry the aim is to establish the absorbed dose to water, D w, under reference conditions. However, existing dosimetry protocols are not always applicable for rapidly emerging new treatment modalities. For primary standard dosimetry laboratories it is generally not feasible to acquire such modalities. Therefore it is strongly desired that D w measurements with primary standards can be performed on-site in clinical beams for the new treatment modalities in order to characterize and calibrate detectors. To serve this need, VSL has developed a new transportable water calorimeter serving as a primary D w standard for 60Co and MV-photons including MRI incorporated treatment equipment. Special attention was paid to its operation in different beam geometries and beam modalities including the application in magnetic fields. The new calorimeter was validated in the VSL 60Co beam and on-site in clinical MV-photon beams. Excellent agreement of 0.1% was achieved with previous 60Co field calibrations, i.e. well within the uncertainty of the previous calorimeter, and with measurements performed in horizontal and vertical MV-photon beams. k Q factors, determined for two PTW 30013 ionization chambers, agreed very well with available literature data. The relative combined standard uncertainty (k  =  1) for D w measurements in 60Co and MV-photons is 0.37%. Calibrations are carried out with a standard uncertainty of 0.42% and k Q -factors are determined with a relative standard uncertainty of 0.40%.

  8. 49. Biological dose assessment by the analyses of chromosomal aberrations and CB micronuclei in two victims accidentally exposed to 60Co gamma-rays

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Biological doses were estimated by using the yields of dicentrics plus rings(dic+r) and cytokinesis-block micronuclei (CBMN) for two victims of the 60Co radiation source accident occurred on Mar 6,2001 in the City of Xuchang(victim A), and Jun 26,2001 in the City of Kaifeng(victim B), Henan Province, respectively. The whole blood of the victim A (male, 37 years old) and the victim B (female, 27 years old)

  9. Effects of Nitric Oxide on Growth and Sensitivity of Human Glioma A172 Cells to 60Co and X-ray Radiation

    Institute of Scientific and Technical Information of China (English)

    QiuRong; LiuBing; GuoChuanling; LiWenjian; MaQiufeng; LiSha

    2003-01-01

    Nitric oxide (NO)has been implicated both in regression and progression of tumors due to its production by both tumor cells and infiltrating lymphocytes. Ionizing radiation causes the regression of tumors, and can augment the production of NO by macrophages in vitro. The authors examined the effect of nitric oxide (NO) generating agent sodium nitroprusside (SNP) on the growth and radiosensitivity of cultured glioma A172 cells to 60Co or X-ray radiation.

  10. Pre-assessment of dose rates of (134)Cs, (137)Cs, and (60)Co for marine biota from discharge of Haiyang Nuclear Power Plant, China.

    Science.gov (United States)

    Li, Jingjing; Liu, Senlin; Zhang, Yongxing; Chen, Ling; Yan, Yuan; Cheng, Weiya; Lou, Hailin; Zhang, Yongbao

    2015-09-01

    Haiyang Nuclear Power Plant to be built in China was selected as a case for the dose pre-assessment for marine biota in this study. The concentrations of Cs and Co in organisms (turbot, yellow croaker, swimming crab, abalone, sea cucumber, and sea lettuce), seawater, and bottom sediment sampled on-site were measured by neutron activation analysis, and the site-specific transfer parameters (concentration ratios and distribution coefficients) of Cs and Co were calculated. (134)Cs, (137)Cs, and (60)Co activity concentrations in the organisms and the sediment at the site were calculated with the site-specific transfer parameters and the anticipated activity concentrations in the liquid effluent of the nuclear power plant. The ERICA tool was used to estimate the dose rates of (134)Cs, (137)Cs, and (60)Co to the selected organisms based on the biological models developed. The total dose rates of (134)Cs, (137)Cs, and (60)Co to the six organisms were all <0.001 μGy h(-1).

  11. A comparison of the 60Co gamma radiation hardness, breakdown characteristics and the effect of SiNx capping on InAlN and AlGaN HEMTs for space applications

    Science.gov (United States)

    Smith, M. D.; O'Mahony, D.; Vitobello, F.; Muschitiello, M.; Costantino, A.; Barnes, A. R.; Parbrook, P. J.

    2016-02-01

    Electrical performance and stability of InAlN and AlGaN high electron mobility transistors (HEMTs) subjected 9.1 mrad of 60Co gamma radiation and off-state voltage step-stressing until breakdown are reported. Comparison with commercially available production-level AlGaN HEMT devices, which showed negligible drift in DC performance throughout all experiments, suggests degradation mechanisms must be managed and suppressed through development of advanced epitaxial and surface passivation techniques in order to fully exploit the robustness of the III-nitride material system. Of the research level devices without dielectric layer surface capping, InAlN HEMTs exhibited the greater stability compared with AlGaN under off-state bias stressing and gamma irradiation in terms of their DC characteristics, although AlGaN HEMTs had significantly higher breakdown voltages. The effect of plasma-enhanced chemical vapour deposition SiNx surface capping is explored, highlighting the sensitivity of InAlN HEMT performance to surface passivation techniques. InAlN-SiNx HEMTs suffered more from trap related degradation than AlGaN-SiNx devices in terms of radiation hardness and step-stress characteristics, attributed to an increased capturing of carriers in traps at the InAlN/SiNx interface.

  12. Dose in sensitive organs during the prostate treatment with a {sup 60}Co unit; Dosis en organos sensibles durante el tratamiento de prostata con una unidad de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Apdo. Postal 336, 98000 Zacatecas (Mexico); Navarro B, J. A. [Universidad Autonoma de Zacatecas, Unidad Academica de Fisica, Carretera a la Bufa s/n, Zacatecas (Mexico); Perez A, M. L.; Perez L, L. H., E-mail: fermineutron@yahoo.com [Instituto Zacatecano del Tumor, A. C., Lago de la Encantada No. 294, Fracc. Lomas del Lago, Zacatecas (Mexico)

    2012-10-15

    The absorbed dose by the bladder, the rectum and the gland thyroid was measured during a treatment applied for prostate cancer by means of a Cobalt 60 unit. The dose was measured using thermoluminescent dosimeters of the type TLD 100, with the values of the absorbed the values of the effective dose were calculated and was determined the probability of the development of a secondary cancer. Because these measurements cannot be made -in vivo- a phantom or mannequin was built with water that represents the hip and part of the torso of the human body and to represent the neck was used polyethylene. The study was carried out in the Instituto Zacatecano del Tumor that has a -cobalt bomb- which is used to treat oncology patients, during the phantom irradiation a dose of 200 c Gy was applied of this dose the bladder received 96.7%, the rectum 100.8% and the gland thyroid 0.3%. The dose received by the rectum and the bladder is due to the therapeutic beam while the dose received by the thyroid is due to the dispersed radiation by the phantom. The probability that in these organs a new neoplasm is developed is of 0.033% for the bladder, 0.157% for the rectum and 7.8 x 10{sup -5}% for the thyroid case. (Author)

  13. Identification of gamma-irradiated papaya, melon and watermelon

    Energy Technology Data Exchange (ETDEWEB)

    Marin-Huachaca, N.S.; Mancini-Filho, Jorge E-mail: jmancini@usp.br; Delincee, Henry E-mail: henry.delincee@bfe.uni-karlsruhe.de; Villavicencio, A.L.C.H. E-mail: villavic@net.ipen.br

    2004-10-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a {sup 60}Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0 kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  14. Identification of gamma-irradiated papaya, melon and watermelon

    Science.gov (United States)

    Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

    2004-09-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  15. Y-Irradiation Degradation of Methamidophos

    Institute of Scientific and Technical Information of China (English)

    ZHAO Renbang; BAO Huaying; XIA Lingyun

    2009-01-01

    The irradiation degradation of methamidophos in aqueous solutions by 60Co-γ rays was investigated.The effects of absorbed doses,saturated gas,and the additive of H2O2 on the degradation were also studied.The results showed that the increased with the increase of the irradiation dosage.At certain irradiation dosage,methamidophos could be degraded completely.The degradation rate of methamidophos in the solution saturated with oxygen was higher than those saturated with other gases,which reached 100% when the absorbed dose was 8 kGy.H2O2 degraded methamidophos slowly when it was used alone,but could accelerate the degradation obviously when it was used with irradiation together.

  16. Thermoluminescence properties of irradiated chickpea and corn

    Science.gov (United States)

    Necmeddin Yazici, A.; Bedir, Metin; Bozkurt, Halil; Bozkurt, Hüseyin

    2008-02-01

    A study was carried out to establish a detection method for irradiated chickpea and corn by thermoluminescence (TL) method. The leguminous were packed in polyethylene bags and then the packets were irradiated at room temperature at different doses by 60Co gamma source at 1, 4, 8 and 10 kGy. Minerals extracted from the leguminous were deposited onto a clean aluminum disc and TL intensities of the minerals were measured by TL. It was observed that the extracted samples from both leguminous exhibit good TL Intensity and the TL intensity of glow curves of them increased proportionally to irradiation doses. The TL glow curve of both irradiated leguminous presents a single broad peak below 400 °C. The TL trapping parameters glow peaks were estimated by the additive dose (AD), Tm(Ea)-Tstop and computerized glow curve deconvolution (CGCD) methods. The fading characteristics of glow curves were also recorded up to 6 months.

  17. INCASOY-35: PRIMERA VARIEDAD DE SOYA OBTENIDA EN CUBA A PARTIR DEL EMPLEO DE TÉCNICAS DE IRRADIACIÓN DE RAYOS GAMMA DE 60Co

    Directory of Open Access Journals (Sweden)

    R. Ortiz

    2005-01-01

    Full Text Available La variedad INCASoy-35 fue obtenida a partir de la irradiación de semillas de la variedad INCASoy-15 con dosis de 240 Gy de rayos gamma 60Co; esta variedad se adapta a siembras de primavera, verano e invierno y puede alcanzar rendimientos de 3 t.ha-1 de granos. Tolera las principales plagas y enfermedades y, en especial, resiste el ataque de nemátodos Meloidogyne incognita. En la época adversa de primavera, las semillas han mostrado tolerancia al deterioro. Tiene capacidad de garantizar altas producciones con bajos insumos, por lo que resulta factible para la agricultura cubana.

  18. Supplementary comparison CCRI(I)-S2 of standards for absorbed dose to water in 60Co gamma radiation at radiation processing dose levels

    DEFF Research Database (Denmark)

    Burns, D. T.; Allisy-Roberts, P. J.; Desrosiers, M. F.

    2011-01-01

    rate effect is presented and discussed briefly. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication......Eight national standards for absorbed dose to water in 60Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized...

  19. Magnetocaloric effect and critical behavior in melt-extracted Gd{sub 60}Co{sub 15}Al{sub 25} microwires

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Dawei; Jiang, Sida; Chen, Dongming; Liu, Yanfen; Sun, Jianfei [School of Materials Science and Engineering, Harbin Institute of Technology (China); Shen, Hongxian [School of Materials Science and Engineering, Harbin Institute of Technology (China); Institute of Materials and Department of Physics, University of South Florida, Tampa, FL (United States); Liu, Jingshun [School of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot (China); Phan, Manh-Huong [Institute of Materials and Department of Physics, University of South Florida, Tampa, FL (United States); Wang, Huan; Qin, Faxiang [Institute for Composites Science and Innovation (InCSI), College of Materials Science and Engineering, Zhejiang University, Hangzhou (China)

    2015-09-15

    High-quality Gd{sub 60}Co{sub 15}Al{sub 25} microwires with an average diameter of 40 μm were successfully fabricated by the melt-extraction method. The as-cast microwires undergo a second-order paramagnetic to ferromagnetic (PM-FM) transition at ∝100 K. Large values of the magnetic entropy change (-ΔS{sub M} ∝9.73 J kg{sup -1} K{sup -1}) and the refrigerant capacity (RC ∝732 J kg{sup -1}) are achieved for a field change of 5 T. A careful analysis of critical exponents near the PM-FM transition indicates the significant effects of structural disorder on the long-range ferromagnetic interaction and the magnetocaloric response of the microwires. The excellent magnetocaloric properties make the Gd{sub 60}Co{sub 15}Al{sub 25} microwires very promising for use in magnetic refrigerators operating in the liquid nitrogen temperature range. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Calculation of direct effects of {sup 60}Co gamma rays on the different DNA structural levels: A simulation study using the Geant4-DNA toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Tajik, Marjan; Rozatian, Amir S.H. [Department of Physics, University of Isfahan, Hezar Jarib Street, Isfahan 81746-73441 (Iran, Islamic Republic of); Semsarha, Farid, E-mail: Semsarha@ibb.ut.ac.ir [Institute of Biochemistry and Biophysics (IBB), University of Tehran, P.O. Box: 13145-1384, Tehran (Iran, Islamic Republic of)

    2015-03-01

    In this study, simple single strand breaks (SSB) and double strand breaks (DSB) due to direct effects of the secondary electron spectrum of {sup 60}Co gamma rays on different organizational levels of a volume model of the B-DNA conformation have been calculated using the Geant4-DNA toolkit. Result of this study for the direct DSB yield shows a good agreement with other theoretical and experimental results obtained by both photons and their secondary electrons; however, in the case of SSB a noticeable difference can be observed. Moreover, regarding the almost constant yields of the direct strand breaks in the different structural levels of the DNA, calculated in this work, and compared with some theoretical studies, it can be deduced that the direct strand breaks yields depend mainly on the primary double helix structure of the DNA and the higher-order structures cannot have a noticeable effect on the direct DNA damage inductions by {sup 60}Co gamma rays. In contrast, a direct dependency between the direct SSB and DSB yields and the volume of the DNA structure has been found. Also, a further study on the histone proteins showed that they can play an important role in the trapping of low energy electrons without any significant effect on the direct DNA strand breaks inductions, at least in the range of energies used in the current study.

  1. Optimization of foaming properties of sludge protein solution by 60Co γ-ray/H2O2 using response surface methodology

    Science.gov (United States)

    Xiang, Yulin; Xiang, Yuxiu; Wang, Lipeng; Zhang, Zhifang

    2016-10-01

    Response surface methodology and Box-Behnken experimental design were used to model and optimize the operational parameters of foaming properties of the sludge protein solution by 60Co γ-ray/H2O2 treatment. The four variables involved in this research were the protein solution concentration, H2O2, pH and dose. In the range studied, statistical analysis of the results showed that selected variables had a significant effect on protein foaming properties. The optimized conditions contained: protein solution concentration 26.50% (v/v), H2O2 concentration 0.30% (v/v), pH value 9.0, and dose 4.81 kGy. Under optimal conditions, the foamability and foam stability approached 23.3 cm and 21.3 cm, respectively. Regression analysis with R2 value of 0.9923 (foamability) and 0.9922 (foam stability) indicated a satisfactory correlation between the experimental data and predicted values (response). In addition, based on a feasibility analysis, the 60Co γ-ray/H2O2 method can improve odor and color of the protein foaming solution.

  2. Study on mutagenic effects of rice seeds irradiated by CO2 laser

    Institute of Scientific and Technical Information of China (English)

    LUORongting; ZHANGMingring

    1998-01-01

    Seeds of japonica rice (cv. Zhenuo 2) at two different physiotogical states (dry seeds with water content 13% and wet seeds soaked inthe water for 36 h) were irradiated by CO2 laser in four different power-densities. The seeds rradiated by 200GY of 60Co γ rays and no radiated seeds were used as the controls.

  3. Determination of the correction factor for attenuation, dispersion and production of electrons (K{sub wall}) in the wall of graphite of a ionization chamber Pattern National Type CC01 in fields of gamma radiation of {sup 60}Co; Determinacion del factor de correccion por atenuacion, dispersion y produccion de electrones (K{sub wall}) en la pared de grafito de una Camara de Ionizacion Patron Nacional Tipo CC01 en campos de radiacion gamma de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T.; Morales P, J.; Cruz E, P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-12-15

    It was determined the Kwall correction factor for the wall of graphite of the chamber of the pattern national type CC01 series 133 for a radiation field Gamma of {sup 60}Co. With this end to measured the currents of ionization l(x) as function of the thickness of the wall of the chamber: X=4,8,12,16 and 20 mm.The mensurations for each thickness consisting of three groups, of sizes n = 30 or 60 data for each group; obtaining 8 complete groups of mensurations independent in eight different dates.The determinate the factor carried out using three regression models: lineal, logarithmic and quadratic, models that were tried to validate with the tests of : i) Shapiro-Wilk and {chi}{sup 2} for the normality of the entrance data ii) Tests of Bartlett for variances homogeneity among groups for each thickness iii) The tests of Duncan for the stockings among groups of each thickness, and iv) The tests of adjustment lack (LOF) for the models used. Nevertheless, alone the models of the group of corresponding mensurations at 01-03-2000 17-08-2001 they can be validated by LOF, but not for tests of normality and homogeneity of variances. Among other assignable causes of variation we have: i) The values captured by the system of mensuration of the variables of it influences: pressure, temperature and relative humidity don{sup t} belong together with the existent ones to the moment to capture the l(x). ii) The mensuration room presents flows of air, for what was suited o diminish their volume and to eliminate the flows of air. iii) A protocol settled down of taking of measures that it consisted in: - Pre-irradiation 5 minutes the chamber after the change of polarity and hood change, with a period of stabilization of 5 minutes after the pre-irradiation. - Pre-irradiation for 5 minutes before the taking of the readings, with the object of eliminating variation sources assigned to currents of escapes or due variations to transitory. iv) To realize corrections for relative humidity of

  4. Effect of gamma radiation from {sup 60}C in conservation and quality of pepper fresh and pulp; Efeito da radiacao gama do {sup 60}Co na conservacao e qualidade de pimenta in natura e em polpa

    Energy Technology Data Exchange (ETDEWEB)

    Milagres, Regina Celia Rodrigues de Miranda

    2014-07-01

    Capsicum peppers are among the most used and most valued seasoning spices in the world. They are highly susceptible to post harvest decay, therefore the use of irradiation may contribute to conservation of this fruit which has significant nutritional, economic and social value. Were evaluated the effects of gamma radiation of {sup 60}Co in increasing the shelf-life and preservation of quality of pepper 'Dedo-de-moca' (Capsicum baccatum var. Pendulum) fresh and pulp associated or not with another conservation methods. Gamma radiation doses were investigated of 0,25; 0,50; 0,75; 1,00; 1,25; 1,50; 2,00 e 3,00 kGy in fresh fruit and 1,50; 2,00; 3,00; 4,50 e 6,00 kGy in pepper pulp. The use of laboratory pasteurization (85°C/3min), the addition of citric acid (5%) and 5% NaCl were also investigated in the pepper pulp. The samples were stored at 5 °C and or 25 °C. Were performed analysis: visual (disease incidence, turgidity and color); bioactive compounds (carotenoids, capsaicinoids, antioxidant capacity and phenolic compounds); physicochemical (Weight loss, firmness, soluble solids (SS), pH, titratable acidity (TA), ratio, color and moisture); respiratory rate and ethylene production; proximate composition (moisture, soluble and insoluble fiber, ash, protein, ether extract, total and available carbohydrate); microbiological contamination (mesophilic aerobic microorganisms, coliforms at 45 °C, Salmonella spp. and yeasts and molds) and sensory (acceptance test, difference test and paired preference). Radiation doses between 0.25 and 3.00 kGy were not effective to increase shelf-life and maintain fresh pepper quality during storage. There was increased intensity of red color, of incidence of disease, decreased turgidity and changes in physical, chemical and nutritional parameters. In pulp, the doses of gamma radiation of 4.50 and 6.00 kGy and the addition of 5% NaCl no changing sensory attributes, physical-chemical and bioactive compounds. Only the

  5. Dose-dependent and gender-related radiation-induced transcription alterations of Gadd45a and Ier5 inhuman lymphocytes exposed to gamma ray emitted by (60)Co.

    Science.gov (United States)

    Tavakoli, Hassan; Manoochehri, Mahdi; Modarres Mosalla, Sayed Mahdi; Ghafori, Mostafa; Karimi, Ali Akbar

    2013-04-01

    Growth arrest DNA damage-inducible 45a gene (Gadd45a) and immediate early response gene 5 (Ier5) have been emphasised as ideal radiation biomarkers in several reports. However, some aspects of radiation-induced transcriptional alterations of these genes are unknown. In this study, gender-dependency and dose-dependency as two factors that may affect radiation-induced transcription of Gadd45a and Ier5 genes were investigated. Human lymphocyte cells from six healthy voluntary blood donors (three women and three men) were irradiated in vitro with doses of 0.5-4.0 Gy from a (60)Co source and RNA isolated 4 h later using the High Pure RNA Isolation Kit. Dose and gender dependency of radiation-induced transcriptional alterations of Gadd45a and Ier5 genes were studied by quantitative real-time polymerase chain reaction. The results showed that as a whole, Gadd45a and Ier5 gave responses to gamma rays, while the responses were independent of radiation doses. Therefore, regardless of radiation dose, Gadd45a and Ier5 can be considered potential radiation biomarkers. Besides, although radiation-induced transcriptional alterations of Gadd45a in female and male lymphocyte samples were insignificant at 0.5 Gy, at other doses, their quantities in female samples were at a significantly higher level than in male samples. Radiation-induced transcription of Ier5 of females samples had a reduction in comparison with male samples at 1 and 2 Gy, but at doses of 0.5 and 4 Gy, females were significantly more susceptible to radiation-induced transcriptional alteration of Ier5.

  6. Trials to identify irradiated chestnut (Castanea bungena) with different analytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H.-W. E-mail: chunghw@kfda.go.kr; Delincee, Henry; Han, S.-B.; Hong, J.-H.; Kim, H.-Y.; Kim, M.-C.; Byun, M.-W.; Kwon, J.-H

    2004-10-01

    Photostimulated luminescence (PSL) measurement, DNA comet assay, electron spin resonance (ESR) spectroscopy and thermoluminescence (TL) measurement were applied to identify irradiated chestnut. Samples were irradiated with {sup 60}Co {gamma}-rays at 0-0.5 kGy. The PSL photon counts for irradiated chestnuts were too low to be distinguished from those of the non-irradiated sample. There was no difference in DNA comets between non-irradiated and irradiated chestnuts. ESR spectroscopy did not show any radiation-induced specific signals but a symmetric singlet. However, using TL, the shape of the glow curve (Glow 1) made it possible to identify the irradiated chestnuts. In addition, the TL glow ratio (Glow 1/Glow 2) obtained by normalization was less than 0.01 for the non-irradiated sample and {>=}0.10 for irradiated ones, respectively.

  7. Effect of a killed whole Neospora caninum tachyzoite vaccine on the crude abortion rate of Costa Rican dairy cows under field conditions.

    Science.gov (United States)

    Romero, J J; Pérez, E; Frankena, K

    2004-09-02

    A standard field trial was carried out to assess the effect of a commercial Neospora-vaccine based on whole killed tachyzoites (Bovilis-Neoguard, Intervet) on the abortion rate. Eight hundred and seventy-six cows, over 2.5 months pregnant, belonging to 25 Costa Rican dairy herds, were used in the analysis. For each cow vaccinated, a cow of the same herd, breed and age category, was selected as control. The period of administration of treatments extended from June to November of 2000. The treatments were administered in two, 5-ml doses 1 month apart, the first dose given between day 75 and 90 of gestation. The incidence of abortion among all treated cows was of 16.0% (140/876). The treatment specific incidence was 11.2% (49/438) and 20.8% (91/438) for the vaccinated and the placebo group, respectively. The prevented fraction by vaccination amounted to 0.46 (95% CI: 0.26, 0.61), and the cumulative incidence ratio for the vaccinated group was 0.54. The Cox hazard ratio was 0.51(95% CI: 0.37, 0.72), meaning that the force of abortion is reduced twice in the vaccinated group. The results of this study, the first one following this type of design, shows that the killed whole Neospora caninum tachyzoite preparation had a reasonable effect on the abortion rate in Costa Rican dairy cattle.

  8. On the efficacy and safety of vaccination with live tachyzoites of Neospora caninum for prevention of neospora-associated fetal loss in cattle.

    Science.gov (United States)

    Weber, Fred H; Jackson, James A; Sobecki, Brian; Choromanski, Les; Olsen, Mary; Meinert, Todd; Frank, Rodney; Reichel, Michael P; Ellis, John T

    2013-01-01

    Infection of cattle with Neospora caninum may result in abortion or the birth of a congenitally infected calf. Vaccination with live N. caninum protects against experimental infection of cattle and mice, and the naturally attenuated Nc-Nowra strain of N. caninum is of particular interest as a potential vaccine candidate. Vaccination of heifers prior to breeding with live Nc-Nowra tachyzoites by either the subcutaneous or the intravenous route reduced the rate of abortion and the presence of the parasite in calves as determined by PCR and serology after infection of cows with a virulent isolate. Protected fractions were 55.6% to 85.2% depending on the route of vaccination and growth conditions of the vaccine strain, with cryopreserved Nc-Nowra tachyzoites being less effective, with a 25.9% protected fraction. Vaccination appeared to reduce the rate of pregnancy after artificial insemination in some groups compared to nonvaccinated, nonchallenged controls. One animal that was vaccinated but not challenged experienced an abortion, but Nc-Nowra could not be detected in any of the cows in this group or their progeny. This study confirms that live vaccination can be an effective method of preventing neosporosis in cattle and yet highlights the technical hurdle of preservation of live parasites that must be overcome for a vaccine to be commercially successful.

  9. Cytogenetic and dosimetric effects of {sup 131}I in lymphocyte of patients with differentiated thyroid cancer with and without r-hTSH stimulation. Study in thyroid tumor cells (WRO) treated with {sup 131}I and {sup 60}Co in vitro; Efeitos citogenetico e dosimetrico do {sup 131}I em pacientes com cancer diferenciado da tireoide com e sem estimulacao com r-hTSH. Estudo em celulas tumorais tireoidianas (WRO) tratadas com {sup 131}I e {sup 60}Co in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Valgode, Flavia Gomes Silva

    2015-11-01

    significance, with or without r-hTSH. However, the cytotoxic assay, showed a tendency to decrease at higher concentrations of 1.85 (p <0.05) and 3.70 MBq/ml (p <0.01) only in the presence of r-hTSH, coincident with the highest level of uptake. WRO cells were also relatively radioresistant to external irradiation of {sup 60}Co in the range of 0.2-8.3 Gy, with a gradual decrease in function of time for higher doses (10,20 and 40Gy).The data obtained showed little cytogenetic damage in patients upon therapeutic exposure, suggesting a safe and effective treatment for both groups of patients. Patients in group A, however, had a better quality of life by using r-hTSH. In vitro studies with internal ({sup 131}I) and external ({sup 60}Co) irradiation, with or without r-hTSH, point to the need for an alternative therapeutic strategy to overcome the loss of ability of thyroid cells (WRO) to concentrate radioiodine, which is responsible for the failure of radioiodine therapy in patients with DTC. (author)

  10. Polymerization of vinyl acetate in bulk and emulsion by gamma irradiation

    Science.gov (United States)

    Mesquita, Andrea C.; Mori, Manoel N.; Andrade e Silva, Leonardo G.

    2004-09-01

    The vinyl acetate polymerization to produce poly(vinyl acetate) was carried out in bulk and emulsion using a 60Co gamma irradiator Gammacell-220 type. The irradiation was carried out in a dose rate of 5.25 and 5.30 kGy/h, respectively. The polymers obtained were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and gel permeation chromatography (GPC). Tests of density, hardness and Vicat softening temperature were carried out.

  11. Study of {sup 137}Cs e {sup 60}Co sorption in sediments from Saco de Piraquara de Fora, Angra dos Reis and its application for environmental monitoring; Estudo da sorcao de {sup 137}Cs e {sup 60}Co em sedimentos do Saco de Piraquara de Fora em Angra dos Reis e sua aplicacao para o monitoramento ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ingryd Marques

    2016-08-01

    Both the suspended solid particles and the bed sediments sorb radionuclides, released in water systems. Sorption is usually represented mathematically by the distribution coefficient that is based in equilibrium between phases. Here the adsorption/desorption kinetics of {sup 60}Co and {sup 137}Cs in sea water were simulated by batch equilibrium experiments with sediments in two points (PT - 01, PT - 02) from Saco de Piraquara de Fora inlet (SPF). For both radionuclides, partition coefficient values (Kd) for the sampling point PT - 02 (509 and 385 L/kg for {sup 60}Co and {sup 137}Cs, respectively) were higher than the values determined for PT - 01 one (426 and 182 L/kg for {sup 137}Cs and {sup 60}Co, respectively). The higher values of Kd of PT-02 reflects the higher CEC (71,4 cmolc.dm{sup 3}) and content of mud < 63 μm (87%) when compared to PT-01 (CEC of 39,5 cmol{sub c}.dm{sup 3}) and mud (55%). In comparison with the values reported in the literature, the found Kd values are low, which may be related to the predominance of kaolinite, which is a clay of low sorption capacity. The Kd values with an increase in temperature of 23 deg C to 27 deg C were similar ({sup 60}Co in PT-02 and {sup 137}Cs in both sediment) or 27 ° C values were higher ({sup 60}Co the PT-01). With increasing temperature to 31 °C Kd values for the two radionuclides showed a decrease. However, increasing temperature increases the desorption of the two radionuclides for both sediments The sorption process is spontaneous and favorable for both sediments and the model of sorption can be fitted by both Freundlich and Langmuir sorption isotherms. The maximum amount of {sup 60}Co that can be sorbed on sediments were 1,64 10{sup -5} moles/g (4,12 10{sup 10} Bq/g) and 2,79 10{sup -5} moles/g (7,03 10{sup 10} Bq/g) to PT-01 and PT-02, respectively, and of {sup 137}Cs 1,99 10{sup -6} moles/g (9,70 10{sup 8} Bq/g) and 6,60 10{sup -6} mol/g (2,87 10{sup 9} Bq/g ) to PT-01 and PT-02. Two areas in SPF can

  12. Food-irradiation technology and reconsideration for the safety of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Aibara, Kageaki (National Inst. of Health, tokyo (Japan))

    1984-08-01

    In the first half of this paper, the definition of several basic concepts on radiation and the units of the quantities related to radiation are given to reconfirm them. In the second half of the paper, the general status of food irradiation technology and irradiated foods are reported. 25 years have elapsed since 1958 when the legal situation of food irradiation research was clarified in the U.S. as a part of the peaceful uses of atomic energy. The types of radiation authorized for use in food irradiation so far are ..gamma..-ray from /sup 60/Co and /sup 137/Cs, X-ray lower than 5 MeV, and electron beam lower than 10 MeV. Large scale irradiation plants operating in the world are listed. The biological effect of radiation includes sterilization, insecticide and growth control, and the sterilization effect further includes radappertization, radicidation and radurization. The insecticide and growth control are also divided into several categories. For these, respective examples of food concerned are listed. The trend of irradiated foods in the world shows that the irradiation treatment of foods is permitted over a wide range of foods. In 1980, the conclusion of the Joint Expert Committee on Integrity of Irradiated Foods of FAO/IAEA/WHO was issued. In the paper, the table of legally authorized irradiated foods in 20 countries in the world is given at the end.

  13. Preparation of Plate Fe60Co8Zr10Mo5W2B15 Bulk Amorphous Alloy and Its Fracture Toughness

    Institute of Scientific and Technical Information of China (English)

    XIAO Huaxing; CHEN Guang

    2005-01-01

    With processes of arc melting, inductive melting and copper mold suction casting, a plate Fe-based bulk amorphous alloy Fe60Co8Zr10Mo5W2B15 with a thickness of 1mm was prepared. The surfaces and fractures of the cast bulk amorphous alloy were agleam and with typical metallic luster. The glass transition temperature(Tg), supercooled liquid region(△Tx)and reduced glass transition temperature(T rg)of the prepared Fe-based amorphous alloy are 884 K,63 K, and 0.611 respectively. The fracture toughness of the cast bulk amorphous alloy is at the level of 1.6 MPa·m1/2.

  14. Supplementary comparison CCRI(I)-S2 of standards for absorbed dose to water in {sup 60}Co gamma radiation at radiation processing dose levels

    Energy Technology Data Exchange (ETDEWEB)

    Burns, D.T.; Allisy-Roberts, P.J. [Bureau International des Poids et Mesures, Pavillon de Breteuil, F-92312 Sevres cedex (France); Desrosiers, M.F. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Sharpe, P.H.G. [National Physical Laboratory, Teddington, Middlesex (United Kingdom); Pimpinella, M. [Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, Rome (Italy); Lourenco, V. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Gif-sur-Yvette (France); Zhang, Y.L. [National Institute of Metrology, Beijing (China); Miller, A. [Riso High Dose reference Laboratory, Riso DTU, Roskilde (Denmark); Generalova, V. [Institute for Physical-Technical and Radiotechnical Measurements, Moscow (Russian Federation); Sochor, V. [Czech Metrology Institute, Brno (Czech Republic)

    2011-06-15

    Eight national standards for absorbed dose to water in {sup 60}Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized by the Bureau International des Poids et Mesures, who also participated at the lowest dose level using their radiotherapy-level standard for the same quantity. The national standards are in general agreement within the standard uncertainties, which are in the range from 1 to 2 parts in 10{sup 2}. Evidence of a dose rate effect is presented and discussed briefly. (authors)

  15. Re-evaluation of the product of (W/e)air and the graphite to air stopping-power ratio for 60Co air kerma standards.

    Science.gov (United States)

    Thomson, R M; Rogers, D W O

    2010-07-07

    Experiments which determine the product of (W/e)air, the average energy deposited per coulomb of charge of one sign released by an electron coming to rest in dry air, and (LDelta/rho)Ca, the Spencer-Attix mean restricted mass collision stopping-power ratio for graphite to air, in a 60Co or 137Cs beam are reanalysed. Correction factors, e.g., to account for gaps about a calorimeter core or perturbations due to a cavity's presence, are calculated using the EGSnrc Monte Carlo code system and these generally decrease the value of (W/e)air(LDelta/rho)Ca for each experiment. Stopping-power ratios are calculated for different choices of density correction and average excitation energy (I-value) for graphite. To calculate an average value (W/e)air(LBIPM/rho)Ca for the BIPM air kerma standard, each experimental result is multiplied by the ratio (LBIPM/rho)Ca/(LDelta/Rho)Ca. While individual values of (LDelta/rho)Ca are sensitive to the I-values and density corrections assumed, this ratio varies by less than 0.1% for different choices. Hence, the product (W/e)air(LBIPM/rho)Ca is relatively insensitive to these choices. The weighted mean of the updated data is (W/e)air(LBIPM/rho)Ca=33.68 J C(-1)+/-0.2%, suggesting that the accepted value of 33.97 J C(-1)+/-0.1% is 0.8% too high. This has implications for primary 60Co air kerma standards worldwide and potentially for the choice of graphite I-value and density correction for the calculation of the graphite stopping power, as well as the value of (W/e)air.

  16. Serum metabonomics of rats irradiated by low-dose γ-rays

    OpenAIRE

    HE, YING; Xian-rong SHEN; Deng-yong HOU; Yu-ming LIU; Ding-wen JIANG; Qing-rong WANG; Ke-xian LI; Chen, Wei; Tian-tian QIAN

    2014-01-01

    Objective To explore the effect of low-dose γ-rays on the metabolites in rat serum. Methods Sixteen healthy male SD rats were randomly divided into control group and irradiated group (n=8). The rats in irradiated group were irradiated by 60Co γ-rays with a dose rate of 72mGy/h for 7 days (1 hour per day). At the 7th day after irradiation, blood samples were taken from abdominal aorta to obtain the serum. The metabolic fingerprints of serum were obtained from the two groups of rats, and 1H nuc...

  17. Detection of garlic gamma-irradiated by assay comet

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Alvarez, Damaris L.; Miranda, Enrique F. Prieto; Carro, Sandra; Iglesias Enrique, Isora; Matos, Wilberto [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), Ciudad de La Habana (Cuba)], e-mail: damaris@ceaden.edu.cu

    2009-07-01

    The garlic samples were irradiated in a facility with {sup 60}Co sources, at absorbed dose values of 0-0,15 kGy. The detection method utilized for the identification of the irradiated garlic was biological comet assay. The samples were classified post-irradiation several times. The irradiated samples showed high strand breaks of DNA exhibiting comets of several forms, while the not irradiated and lower dose samples showed a behavior like round shape and light comets. Significant differences were found for higher absorbed dose values at 0.06 kGy, this absorbed dose value is corresponding with the applied dose value at this food in order to avoid the germination. (author)

  18. Gynogenesis in carp, Cyprinus Carpio L. and tench, Tinca Tinca L. induced by 60Co radiation in highly homogeneous radiating field

    Science.gov (United States)

    Pipota, J.; Linhart, O.

    The paper deals with a method of fertility inactivation of fish spermatozoa by gamma radiation. Spermatozoa motility remained unchanged after irradiation. Irradiated sperm has been utilized to induced gynogenesis by means of retention of the second polar body and of mitotic gynogenesis, realized in carp for the first time. Homogeneity of gamma-rays field was + - 1 %.

  19. Design of Indigenous ELISA Using Tachyzoites from the RH Strain of Toxoplasma gondii and Comparison with Commercial Kits in Ahvaz, Southwest of Iran, 2015

    Science.gov (United States)

    Mohammadpour, Niloofar; Saki, Jasem; Rafiei, Abdollah; Khodadadi, Ali; Tavalla, Mehdi; Cheraghian, Bahman

    2016-01-01

    Background Toxoplasma gondii is one of the most common causes of latent infections in humans worldwide. Detecting anti-Toxoplasma antibodies in serum using serological tests is a common method to diagnose toxoplasmosis. Objectives In the present study, an indigenous ELISA kit was prepared using tachyzoites from the RH strain of T. gondii, and its sensitivity and specificity were compared with those of commercial kits. Methods To produce antigens, 0.02 mL of locally isolated T. gondii RH strain parasites along with 109 tachyzoites were injected into the peritoneal cavities of 50 laboratory mice (BALB/C). Parasites were collected after 4 days. After filtering and washing, the concentration of protein in sonicated tachyzoites was calculated using the Lowry protein assay. The dilution of antigen, serum and alkaline phosphatase conjugate was assessed in designing an indigenous ELISA method; then ELISA was performed based on these dilutions, and its sensitivity was determined using 200 serum samples. In addition, the specificity of the assay was evaluated using 40 serum samples from patients with tuberculosis, leukemia or hydatid cyst. Results Indigenous ELISA was used to examine 100 serum samples containing anti-T. gondii IgG, with a sensitivity of 98% (commercial kits: 100%). Another 100 serum samples containing anti-T. gondii IgM were also tested, with a sensitivity of 99% (commercial kits: 100%). When 40 serum samples from patients with leukemia, hydatid cyst or tuberculosis were examined using anti-T. gondii IgG, the specificity was 100%, identical to commercial kits. However, the specificity of a similar test with anti-T. gondii IgM was just 28.6% for serum samples from leukemia patients, 21.4% for hydatid cyst and 16.7% for tuberculosis. Conclusions We found that purified locally isolated soluble crude antigens of the RH strain of T. gondii from the peritoneal cavity of mice may be one of the most promising antigens for detection of human toxoplasmosis in routine

  20. Raman and AFM study of gamma irradiated plastic bottle sheets

    Science.gov (United States)

    Ali, Yasir; Kumar, Vijay; Sonkawade, R. G.; Dhaliwal, A. S.

    2013-02-01

    In this investigation, the effects of gamma irradiation on the structural properties of plastic bottle sheet are studied. The Plastic sheets were exposed with 1.25MeV 60Co gamma rays source at various dose levels within the range from 0-670 kGy. The induced modifications were followed by micro-Raman and atomic force microscopy (AFM). The Raman spectrum shows the decrease in Raman intensity and formation of unsaturated bonds with an increase in the gamma dose. AFM image displays rough surface morphology after irradiation. The detailed Raman analysis of plastic bottle sheets is presented here, and the results are correlated with the AFM observations.

  1. X-ray versus gamma irradiation effects on polymers

    Energy Technology Data Exchange (ETDEWEB)

    Croonenborghs, B. [Sterigenics EMEAA, Remylaan 4c box 4, 3018 Leuven (Belgium); Smith, M.A. [Sterigenics International, 10811 Withers Cove Park Drive, Charlotte, NC 28278 (United States); Strain, P. [Sterigenics EMEAA, Remylaan 4c box 4, 3018 Leuven (Belgium)], E-mail: pstrain@eu.sterigenics.com

    2007-11-15

    Today, the most common methods used for medical device sterilisation are by gaseous ethylene oxide and by electron beam or gamma irradiation. With X-ray sterilisation about to enter the market, its material compatibility needs to be assessed at doses typically encountered during a sterilisation process. This paper reports on a study that compares the effects of exposing different types of plastics that are commonly used in medical devices to {sup 60}Co or to 5 MeV X-rays. The dose rate for both irradiation modalities was of the same order of magnitude. Under these conditions, both types of radiation are found to have similar effects on polymer properties.

  2. EPR identification of irradiated Monascus purpureus red pigment

    Energy Technology Data Exchange (ETDEWEB)

    Duliu, Octavian G. E-mail: odlu@scut.fizica.unibuc.ro; Ferdes, Mariana; Ferdes, Ovidiu S

    2000-01-01

    Fresh red alimentary pigment extracted from Monascus purpureus fungus exhibits an intense EPR line consisting of a single, narrow line, attributed to a quinone radical. When irradiated with 7 MeV electrons or {sup 60}Co {gamma}-rays, the amplitude of this line increased with the absorbed dose following a saturation exponential dependency up to 10 kGy. During annealing treatment (isothermal heating at 100 deg. C) the irradiation centers decay exponentially with a half-life time of 2.30 min.

  3. EPR identification of irradiated Monascus purpureus red pigment

    Science.gov (United States)

    Duliu, Octavian G.; Ferdes, Mariana; Ferdes, Ovidiu S.

    2000-01-01

    Fresh red alimentary pigment extracted from Monascus purpureus fungus exhibits an intense EPR line consisting of a single, narrow line, attributed to a quinone radical. When irradiated with 7 MeV electrons or 60Co γ-rays, the amplitude of this line increased with the absorbed dose following a saturation exponential dependency up to 10 kGy. During annealing treatment (isothermal heating at 100°C) the irradiation centers decay exponentially with a half-life time of 2.30 min.

  4. Toxoplasmosis: The spread of tachyzoites, cysts and oocysts%弓形虫病:速殖子、包囊和卵囊的传播

    Institute of Scientific and Technical Information of China (English)

    汪涛; 汤自豪

    2012-01-01

    Toxo plasma gondii is widely distributed opportunistic pathogenic within the world, which can infect all warm-blooded animals including human and cause zoonotic toxoplasmosis , seriously throating human health and livestock production . This article focuses on the biological characteristics and transmission feature of Toxop lasma gondii tachyzoite , cysts and oocysts.%目的 弓形虫是一种世界范围内广泛分布的机会致病原虫,能感染包括人在内的所有温血动物,能引起人兽共患弓形虫病,严重威胁着人类健康和畜牧业生产.本文重点阐述弓形虫速殖子、包囊和卵囊的生物学特性和传播特点.

  5. Characterization on the microstructure of gamma-ray irradiated Nd2Fe14B magnet.

    Science.gov (United States)

    Han, Young Chul; Kim, Young Hwan; Cha, Hyun Gil; Kim, Chang Woo; Ji, Eun Sun; Heo, Jin Kook; Kwon, Hae Woong; Kang, Young Soo

    2009-02-01

    The effect of 60Co gamma-ray irradiation on the microstructure of Nd2Fe14B magnets was investigated with electron spin resonance (ESR) and thermal mechanical analyzer (TMA). When the 60Co gamma-ray with dose from 0 Mrad to 100 Mrad was exposed to Nd2Fel,4B magnet having different sizes at room temperature, the increased demagnetization properties of the Nd2Fe14B magnets were studied by Hall probe. For all samples, changed Curie temperature and micro-crystal structure of Nd2Fe14B magnet by gamma-ray irradiation has been also studied. Moreover the strong and broad single line shaped ESR signal in the resonance magnetic field is attributed to unpaired electron of iron ions in the sample by the effect of gamma-ray irradiation.

  6. Sublethal Irradiation Promotes Migration and Invasiveness of Prostate Cancer PC-3 Cells: Implications for Radiotherapy of Human Prostate Cancer

    Institute of Scientific and Technical Information of China (English)

    Xiaoyi Zhang; Baofa Hong; Jianguang Zhou; Liquan Zhou; Lian Zou

    2007-01-01

    OBJECTIVE To study the changes in the matrix metalloproteinases-2 and 9 (MMP2, MMP9) induced by 60Co y-ray external irradiation of human prostate cancer PC-3 cells.METHODS Human prostate cancer PC-3 cells were irradiated with different doses of 60Coy-rays. Cell migration and invasiveness were evaluated and the expression of MMP2, and MMP9 was investigated by RT-PCR, Western blotting and flow cytometry(FCM).RESULTS Irradiation enchances invasive protential at the doses of 1,3 and 5 Gy.whereas it significantly inhibits cell migration. CONCLUSION The different doses of 60Co y-ray external irradiation for prostate cancer may have different effects through the changes of MMP2, and MMP9 expression.

  7. Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the LNE-LNHB, France and the BIPM in 60Co gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D. T.; Delaunay, F.; Donois, M.

    2013-01-01

    An indirect comparison of the standards for air kerma of the Laboratoire National de Métrologie et d'Essais-Laboratoire National Henri Becquerel (LNE-LNHB), France and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in April 2013. The comparison result, evaluated as a ratio of the LNE-LNHB and the BIPM standards for air kerma, is 0.9994 with a combined standard uncertainty of 1.8 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  8. KEY COMPARISON: Comparison of the standards for absorbed dose to water of the BNM-LNHB and the BIPM for 60Co γ rays

    Science.gov (United States)

    Allisy-Roberts, P. J.; Burns, D. T.; Kessler, C.; Delaunay, F.; Leroy, E.

    2005-01-01

    A comparison of the standards for absorbed dose to water of the Bureau National de Métrologie - Laboratoire National Henri Becquerel (BNM-LNHB), Saclay, France and of the Bureau International des Poids et Mesures (BIPM) has been made in 60Co radiation under the auspices of the key comparison BIPM.RI(I)-K4. The comparison result expressed as a ratio of the BNM-LNHB and the BIPM standards for absorbed dose to water is 0.9970 (0.0053). The degrees of equivalence between the BNM-LNHB and the other participants in this comparison have been calculated and the results are given in the form of a matrix for the 12 national metrology institutes (NMIs) that have taken part in the ongoing comparison for absorbed dose to water. A graphical presentation is also given. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section I of the Consultative Committee for Ionizing Radiation (CCRI(I)), according to the provisions of the Mutual Recognition Arrangement (MRA).

  9. Comparison of the standards for absorbed dose to water of the NRC and the BIPM for {sup 60}Co gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, C.; Allisy-Roberts, P.J.; Burns, D.T. [Bureau International des Poids et Mesures (BIPM), 92 - Sevres (France); McCaffrey, J.P.; McEwen, M.R.; Ross, C.K. [National Research Council of Canada, Ottawa (Canada)

    2010-06-15

    A comparison of the standards for absorbed dose to water of the National Research Council of Canada (NRC) and of the Bureau International des Poids et Mesures (BIPM) was carried out in the {sup 60}Co radiation beam of the BIPM in May 2009 under the auspices of the key comparison BIPM.RI(I)-K4. The comparison result, based on the calibration coefficients for two transfer standards and expressed as a ratio of the NRC and the BIPM standards for absorbed dose to water, is 0.9980(52). This result replaces the 1998 NRC value of 0.9976(51) in this key comparison. The degrees of equivalence between the NRC and the other participants in this comparison have been calculated and the results are given in the form of a matrix for the ten national metrology institutes (NMIs) with published results that have taken part in the ongoing comparison for absorbed dose to water. A graphical presentation is also given. (authors)

  10. Monitoring of tritium, 60Co and 137Cs in the vicinity of the warm water outlet of the Paks Nuclear Power Plant, Hungary.

    Science.gov (United States)

    Janovics, R; Bihari, Á; Papp, L; Dezső, Z; Major, Z; Sárkány, K E; Bujtás, T; Veres, M; Palcsu, L

    2014-02-01

    Danube water, sediment and various aquatic organisms (snail, mussel, predatory and omnivorous fish) were collected upstream (at a background site) and downstream of the outlet of the warm water channel of Paks Nuclear Power Plant. Gamma emitters, tissue free-water tritium (TFWT) and total organically-bound tritium (T-OBT) measurements were performed. A slight contribution of the power plant to the natural tritium background concentration was measured in water samples from the Danube section downstream of the warm water channel. Sediment samples also contained elevated tritium concentrations, along with a detectable amount of (60)Co. In the case of biota samples, TFWT exhibited only a very slight difference compared to the tritium concentration of the Danube water, however, the OBT was higher than the tritium concentration in the Danube, independent of the origin of the samples. The elevated OBT concentration in the mollusc samples downstream of the warm water channel may be attributed to the excess emission from the nuclear power plant. The whole data set obtained was used for dose rate calculations and will be contributed to the development of the ERICA database.

  11. Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the SCK.CEN, Belgium and the BIPM in 60Co gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D.; Mihailescu, L. C.; Chiriotti, S.

    2017-01-01

    A first key comparison of the standards for air kerma of the Laboratory for Nuclear Calibrations (LNK) from the Studiecentrum voor Kernenergie—Centre d'Etude de l'Energie Nucleaire (SCK.CEN), Belgium and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in September 2016. The comparison result, evaluated as a ratio of the SCK.CEN and the BIPM standards for air kerma, is 1.0021 with a combined standard uncertainty of 2.6 × 10-3. The results for an indirect comparison made at the same time are consistent with the direct results at the level of 7 parts in 104. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  12. Effects of {sup 60}Co gamma radiation on toxicity and hemorrhagic, myonecrotic, and edema-forming activities of Cerastes cerastes venom

    Energy Technology Data Exchange (ETDEWEB)

    Abib, H. [Univ. des Sciences et de la Technologie, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Houari Boumedienne, Bab Ezzouar (Algeria); Laraba-Djebari, F. [Inst. Pasteur d' Algerie, Lab. de Recherche et de Developpement sur les Venins, Alger (Algeria)]. E-mail: flaraba@ibnsina.ands.dz

    2003-12-01

    Antisera are used as effective antidotes against the local effects of snake bites. To improve antisera production and extend the life of surrogates used to produce antibodies, the chronic effects of venom toxicity must be reduced. The present study evaluated the effectiveness of gamma irradiation to reduce the local effects associated with viperid snake bites by evaluating in NMRI mice the toxicity and edematic, hemorrhagic, and myonecrotic activities of native and irradiated Cerastes cerastes venoms. These results indicated that the toxicity of irradiated venoms (1 and 2 kGy) decreased as compared with that of native venom. The edematic and hemorrhagic activities were also reduced in the detoxified samples, particularly with the 2-kGy radiation dose. Furthermore, the creatine phosphokinase (CPK) activity was significantly increased in the serum and decreased in the myocardium after envenomation with native venom, but no significant enzymatic changes were observed in mice envenomated with irradiated venom. Histopathologic evaluation showed that native venom caused severe degenerative changes in the myocardium. In the case of 2-kGy-irradiated venom, no tissue alterations were observed. These results indicate that irradiation of venom with a 2-kGy dose may offer an effective method for reducing the chronic toxic effects of venom in immunized animals. (author)

  13. Utilization of half-embryo test to identify irradiated beans

    Energy Technology Data Exchange (ETDEWEB)

    Villavicencio, Anna Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Mancini-Filho, Jorge [Sao Paulo Univ., SP (Brazil). Faculdade de Ciencias Farmaceuticas; Delincee, Henry [Federal Research Centre for Nutrition - BFE, Karlsruhe (Germany)

    1996-07-01

    Germination tests were carried out in irradiated and non-irradiated bean seeds which allow to observe characteristically variations on the shoots and roots. The methodology used in this work, is based upon biological changes which occur in two Brazilian beans, Phaseolus vulgaris L., var. carioca and Vigna unguiculata (L.) Walp, var. macacar, irradiated in a {sup 60} Co source, with doses of 0,0.5, 1.0, 2.5, 5.0 and 10.0 kGy. The shoots and roots were observed during 3 days of culturing period under specified conditions. The differences observed in these two varieties were analysed immediately after irradiation and after 6 months of storage period at room temperature. Irradiated half-embryos showed markedly reduced root grow and almost totally retarded shoot elongation. Differences between irradiated and nonirradiated half-embryo could be observed after irradiation when different beans and storage time were varied. The shoots of half-embryos irradiated with more than 2.5 kGy did not undergo any elongation, whereas, the shoots of non-irradiated or those beans irradiated under 1.0 kGy elongated significantly within the 3 day test period. (author)

  14. Effect of. gamma. -irradiation in the keeping quality of Nigerian onion cultivars

    Energy Technology Data Exchange (ETDEWEB)

    Agbaji, A.S.; Ogbadu, G.H.; van Amstel, H. (Ahmadu Bello Univ., Zaria (Nigeria). Dept. of Biochemistry)

    1981-01-01

    Onion of variety Ds x Ws'78 and Ds'79 harvested 14 days prior to the experiment were treated with 5, 8 and 15 krad doses of ..gamma..-irradiation from a /sup 60/Co ..gamma..-irradiator and stored. Onions were weekly investigated for sprouting and rotting. Chemical analyses were carried out monthly for dry matter, flavour, ascorbic acid, reducing sugar and protein. In comparison, a local method of storage was carried out. Irradiation dose of 5-15 krad completely inhibited sprouting throughout the whole storage period. Irradiated bulbs however, showed a higher tendency to rot. In comparison with the control, irradiation did not have any significant effect on dry matter, flavour component and ascorbic acid but the protein content was significantly lower in the irradiated bulbs. The compositional differences found between irradiated and untreated onions seem to be of no nutritional or organoleptic significance. Almost 100% loss was recorded for local storage trial.

  15. Statement on the validity and robustness of information provided on irradiated iron oxides

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2014-07-01

    Full Text Available Following a Rapid Alert System for Food and Feed (RASFF notification concerning the use of an unauthorised irradiated colouring agent (brown iron oxide as coatings of food supplements, the European Commission asked EFSA to assess the scientific validity and robustness of three documents i two safety assessments from two pharmaceutical companies including information on the manufacturing process of iron oxides, and ii one safety assessment on gamma irradiated iron oxides in food supplements provided by a consultant. According to the supplier of iron oxides and hydroxides (E 172, the aim of the 60Co-gamma irradiation treatment was to eliminate microbiological contamination. Iron oxides and hydroxides (E 172 are authorised food additives in the EU. EFSA noted that the gamma irradiation of iron oxides (yellow, red, black and brown has not been previously evaluated by other Scientific Committees dealing with foodstuffs, pharmaceutical products or cosmetics and that the irradiation doses applied to iron oxides in this particular case are higher than the doses currently authorised in the EU for “other food and food ingredients”. EFSA also noted that some evidence is available in the literature demonstrating a reduction of iron(III to iron(II due to 60Co-gamma irradiation and, that the food additive black iron oxide, as authorised in the EU, contains iron in both (II and (III valence states. Therefore, an increase in the content of divalent iron would not be of safety concern per se. However, EFSA also notes that the information on irradiated iron oxides provided is very limited and insufficient to substantiate the claim that iron oxides are not expected to undergo any chemical transformation upon irradiation. In order to demonstrate the chemical stability of iron oxide during the 60Co-gamma irradiation treatment, EFSA recommends to carry out some further analyses.

  16. IMMUNE TOLERANCE INDUCED BY GAMMA-RAY IRRADIATION

    Institute of Scientific and Technical Information of China (English)

    练燕; 王延江; 粟永萍; 冉新泽; 艾国平; 刘晓宏; 郭朝华; 程天民

    2003-01-01

    Objective: To detect the existence of immune tolerance induced by gamma-ray irradiation. Methods: Peritoneal cells were harvested from mice subjected to 5 Gy 60Co gamma-ray total body irradiation at 3d, 7d, 15d and 30d, then their counts, morphological changes and IL-12 gene expression were investigated. Results: After irradiation, the peritoneal cells were sharply reduced, the cell morphology shifted from round-like to polymorphic and fusiform with some processes, expression of IL-12 p35 was seriously suppressed, while that of IL-12 p40 greatly enhanced. Conclusion: Our data highly suggest that the gamma-ray irradiation could potentially induce dendritic cell (DC) commitment and immune tolerance.

  17. Effect of irradiation on the macro- and microstructure of strawberries

    Energy Technology Data Exchange (ETDEWEB)

    Voeroes, Z.; Kovacs, E. (Kerteszeti Egyetem, Budapest (Hungary)); Zackel, E. (Koezponti Elelmiszeripari Kutato Intezet, Budapest (Hungary))

    1985-01-01

    Samples of Gorella, Pocahontas and Rival strawberry varieties were irradiated (2,5 kGy) by means of a sup(60)Co source to increase storage life. The packaged fruits were stored in cabinets of 80-90% relative vapour content at 5 and 10 deg C, respectively. No significant differences could be found in the refraction % and pH values of the irradiated and control samples and of the packeged and unpackaged samples. Due to irradiation the consistency of fruits softened. At the measurements of strawberries with Instron consistometer the optimal quality marks seem to be obtainable by measuring the deformation steadiness. By means of optical microscopy it was stated that the tissue structure of various strawberry varieties did not alter essentially due to irradiation.

  18. Development of food irradiation technology and consumer attitude toward irradiated food in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Joong-Ho; Byun, Myung-Woo; Cho, Han-Ok (Korea Atomic Energy Research Inst., Daeduk (Korea, Republic of))

    1992-12-01

    In Korea, the well-integrated research of biological effects of radiation has been launched from the late 1960s. As research activities, the following food items have been dealt with: sprouting foods, fruits, mushrooms, grains, spices or mixed condiments, fish or fishery products, meat or meat products, and fermented foods. The usage of gamma radiation from [sup 60]Co source is now authorized for food irradiation of the following items: potato, onion, garlic, chestnut, mushroom, dried mushroom, dried spices (including red pepper, garlic, black pepper, onion, ginger, and green onion), dried meat, powdered fish and shellfish, soybean paste powder, hot pepper paste powder, soybean sauce powder, and starch. Since the authorization of food irradiation in 1985, consumers' acceptance has been considered the most important. The survey evaluating the basic perception and attitule toward food irradiation revealed the following results. Consumers' awareness of food irradiation was 82%, with significantly higher in radiation workers than the general public (p<0.0001). Seventy-five percent distinguished the contaminated food by radionuclides from irradiated food. In purchasing irradiated foods, 50.9% required more information. The contribution of irradiated foods to wholesomeness was suspicious in 51%, acceptable in 33%, and uncertain in 16%. If information about the benefits of irradiation is provided to consumers, positive response was increased to 60%. The most critical impediment in the commercial application of food irradiation was found to have resulted from the general consumers' slow acceptance; however, consumers' attitude to irradiated food became positive if they understood the safety and advantages of this technology. The most important task is to overcome consumers' psychological resistance and transporting matters of the products to be irradiated. (N.K.).

  19. Coefficients of leaf-fruit translocation for {sup 60}Co, {sup 90}Sr and {sup 137}Cs in bean plant (Phaseolus vulgaris); Coeficientes de translocacao folha-fruto de {sup 60}Co, {sup 90}Sr e {sup 137}Cs em feijoeiro (Phaseolus vulgaris)

    Energy Technology Data Exchange (ETDEWEB)

    Macacini, Jose Flavio

    2000-01-15

    Due to the increasing use of nuclear fission for the generation of electrical energy, the safety aspects of power plants must be minutely appraised. In case of an accident, with liberation of radioactive material into the atmosphere, knowledge about the behavior of plant species when in contact with radionuclides is indispensable. An important route through which agricultural products are contaminated by radionuclides is leaf-fruit translocation. This phenomenon can be evaluated by simulating a fallout contamination in a controlled atmosphere using as a tracer man-made radionuclides. In order to quantity the leaf-fruit translocation coefficients for {sup 60}Co, {sup 90}Sr and {sup 137}Cs in the common bean (Phaseolus vulgaris), variety black diamond, an experiment was carried out in a greenhouse with completely randomized blocks design with six treatments and four blocks. A mixture of these three radionuclides was prepared and used to determine their translocation coefficients. The bean plants were contaminated inside a device especially designed to avoid environmental contamination. In each treatment four vases were sprinkled and one was used to estimate the initial activity of the other three vases. High-resolution gamma-ray spectrometry was used for {sup 60}Co and {sup 137}Cs activity determinations and chemical separation followed by beta counting of {sup 90}Y was used for {sup 90}Sr determinations. The number of treatments was reduced from six to four sprayings corresponding to 30, 45, 60 and 75 days after planting. This reduction was due to the attack of common and gold mosaic viroses. Symptoms were observed on the diseased bean plants 50 days after planting. It was possible, however, to verify a functional dependence between instant of tracer application and the level of physiological development of the bean plant. It was verified that the temporal relationship values for leaf-fruit translocation were similar for {sup 60}Co and {sup 137}Cs. For the {sup 90

  20. Application of a rapid screening method to detect irradiated meat in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Villavicencio, A.L.C.H. E-mail: villavic@net.ipen.br; Mancini-Filho, J. E-mail: jmancini@usp.br; Delincee, H. E-mail: henrydelincee@bfe.uni-karlsruhe.de

    2000-03-01

    Based on the enormous potential for food irradiation in Brazil, and to ensure free consumer choice, there is a need to find a convenient and rapid method for detection of irradiated food. Since treatment with ionising radiation causes DNA fragmentation, the analysis of DNA damage might be promising. In this paper, the DNA Comet Assay was used to identify exotic meat (boar, jacare and capybara), irradiated with {sup 60}Co gamma rays. The applied radiation doses were 0, 1.5, 3.0 and 4.5 kGy. Analysis of the DNA migration enabled a rapid identification of the radiation treatment.

  1. Application of a rapid screening method to detect irradiated meat in Brazil

    Science.gov (United States)

    Villavicencio, A. L. C. H. A. L. C. H.; Mancini-Filho, J. J.; Delincée, H.

    2000-03-01

    Based on the enormous potential for food irradiation in Brazil, and to ensure free consumer choice, there is a need to find a convenient and rapid method for detection of irradiated food. Since treatment with ionising radiation causes DNA fragmentation, the analysis of DNA damage might be promising. In this paper, the DNA Comet Assay was used to identify exotic meat (boar, jacaré and capybara), irradiated with 60Co gamma rays. The applied radiation doses were 0, 1.5, 3.0 and 4.5 kGy. Analysis of the DNA migration enabled a rapid identification of the radiation treatment.

  2. The green tea extract epigallocatechin-3-gallate inhibits irradiation-induced pulmonary fibrosis in adult rats

    OpenAIRE

    You, Hua; Wei, Li; Sun, Wan-Liang; Wang, Lei; YANG, ZAI-LIANG; Liu, Yuan; Zheng, Ke; Wang, Ying; Zhang, Wei-Jing

    2014-01-01

    The present study evaluated the effect of epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea, on irradiation-induced pulmonary fibrosis and elucidated its mechanism of action. A rat model of irradiation-induced pulmonary fibrosis was generated using a 60Co irradiator and a dose of 22 Gy. Rats were intraperitoneally injected with EGCG (25 mg/kg) or dexamethasone (DEX; 5 mg/kg) daily for 30 days. Mortality rates and lung index values were calculated. The severity of fibr...

  3. Consecutive C[subscript 60] Fullerene Dissociation from Ir([eta][superscript 2]-C[subscript 60])(CO)(Cl)(PPh[subscript 3])[subscript 2] and the Oxidative Addition of Benzene

    Science.gov (United States)

    Felix, Tamara; Cortes-Figueroa, Jose E.

    2010-01-01

    This laboratory activity is a mechanistic exploration of the interactions between electronically deficient organometallic compounds and solvent molecules. Simple kinetics experiments designed to explore the mechanism of C[subscript 60] fullerene-benzene exchange on Ir(([eta][superscript 2]-C[subscript 60])(CO)(Cl)(PPh[subscript 3])[subscript 2]…

  4. Characterization of 60 Co y-radiation induced radical products of antipyrine by means of high performance liquid chromatography, mass spectrometry, capillary zone electrophoresis, micellar electrokinetic capillary chromatography and nuclear magnetic resonance spectrometry

    NARCIS (Netherlands)

    Coolen, S.A.J.; Everaerts, F.M.; Huf, F.A.

    1997-01-01

    Monitoring the amount of oxidative damage, caused by free radicals, is a major problem in free radical and aging research. Antipyrine is proposed as an exogenous marker for the biomolecular monitoring of oxidative stress. In this paper the characterization of the 60Co γ-radiation products of antipyr

  5. The RBE of 3.4 MeV alpha-particles and 0.565 MeV neutrons relative to 60Co gamma-rays for neoplastic transformation of human hybrid cells and the impact of culture conditions.

    Science.gov (United States)

    Frankenberg-Schwager, M; Spieren, S; Pralle, E; Giesen, U; Brede, H J; Thiemig, M; Frankenberg, D

    2010-01-01

    The neoplastic transformation of human hybrid CGL1 cells is affected by perturbations from external influences such as serum batch and concentration, the number of medium changes during the 21-day expression period and cell seeding density. Nevertheless, for doses up to 1.5 Gy, published transformation frequencies for low linear energy transfer (LET) radiations (gamma-rays, MeV electrons or photons) are in good agreement, whereas for higher doses larger variations are reported. The (60)Co gamma-ray data here for doses up to 1.5 Gy, using a low-yield serum batch and only one medium change, are in agreement with published frequencies of neoplastic transformation of human hybrid cells. For 3.4 MeV alpha-particles (LET = 124 keV/mum) and 0.565 MeV monoenergetic neutrons relative to low doses of (60)Co gamma-rays, a maximum relative biological effectiveness (RBE(M)) of 2.8 +/- 0.2 and 1.5 +/- 0.2, respectively, was calculated. Surprisingly, at higher doses of (60)Co gamma-rays lower frequencies of neoplastic transformation were observed. This non-monotonic dose relationship for neoplastic transformation by (60)Co gamma-rays is likely due to the lack of a G2/M arrest observed at low doses resulting in higher transformation frequencies per dose, whereas the lower frequencies per dose observed for higher doses are likely related to the induction of a G2/M arrest.

  6. 60Co-γ射线辐照处理对天竺葵、观赏椒种子发芽率及幼苗的影响%The Effect of 60Co-γRay Radiation on the Germination Rate of Seed and Growth of Seeding of Pelargonium and Capsioum annuum L.

    Institute of Scientific and Technical Information of China (English)

    强继业; 夏更寿; 王海棠; 尹瑞新; 王元军

    2005-01-01

    60Co-γ射线辐照处理天竺葵、观赏椒种子,观察其发芽率和幼苗生长情况.结果表明:γ射线辐射对这2种观赏植物的发芽率和幼苗生长发育具有不同的影响.对天竺葵的发芽率有促进作用,但抑制幼苗生长;对观赏椒发芽率作用不显著,对幼苗前期生长有抑制作用.

  7. Radiation damage of LSO crystals under γ- and 24 GeV protons irradiation

    Science.gov (United States)

    Auffray, E.; Barysevich, A.; Fedorov, A.; Korjik, M.; Koschan, M.; Lucchini, M.; Mechinski, V.; Melcher, C. L.; Voitovich, A.

    2013-09-01

    Irradiation damage of undoped and low Ce doped lutetium oxyorthosilicate has been investigated. Crystals were irradiated with both a 60Co γ-quanta source with an absorbed dose of 2000 Gy and, at CERN PS, a high-rate 24 GeV proton beam with a fluence of ˜3.6×1013 p/cm2. Both irradiations produced a similar set of induced absorption bands. However, a shift of the fundamental absorption spectrum cutoff appears after proton irradiation, but not in the case of the γ-irradiation. The observed shift of the band edge in the transmission spectrum following proton irradiation in lutetium oxyorthosilicate crystals indicates that this phenomenon is a general property of heavy crystalline materials. A possible proton-induced transmission damage mechanism is discussed.

  8. The Effect of Vitamin D3 Alone and Mixed with IFN-γ on Tachyzoites of Toxoplasma Gondii (RH Strain Proliferation and Nitric Oxide (NO Production in Infected Macrophages of BALB/C Mice

    Directory of Open Access Journals (Sweden)

    E Al-Kawaz

    2010-09-01

    Full Text Available Introduction: Toxoplasma gondii is an obligatory interacelullar parasite that infects nucleated cells in its intermediate hosts. The aim of the present study was to determine the effect of vitamin D3 on the multiplication of T. gondii in peritoneal macrophage of Balb/c mice and nitric oxide production by macrophages. Methods: According to usage of vitamin D3 (one dose or seven doses and INFγ in vitro and in vivo, this study was divided into four experiments. In all experiments, the macrophages were col­lected from peritoneum and cultured in RPMI-1640. Then the supernatants were collected after 24 h and their nitric oxide was measure. After 96 h, the macrophages were collected and stained and the number of tachyzoites was measured. Results: The first experiment (the mice were infected with tachyzoites and after 2 h, got one dose vita­min D3 intraperitonealy showed the best results. The mean of tachyzoites per macrophages was 2.37, and mean ± SD of nitric oxide was 187.8 ± 9.Discussion: High-level production of nitric oxide may be related to the only one injection of vita­min D3. The injection in long time might suppress the immune system.

  9. SU-E-T-102: Determination of Dose Distributions and Water-Equivalence of MAGIC-F Polymer Gel for 60Co and 192Ir Brachytherapy Sources

    Energy Technology Data Exchange (ETDEWEB)

    Quevedo, A; Nicolucci, P [University of Sao Paulo, Ribeirao Preto, SP (Brazil)

    2014-06-01

    Purpose: Analyse the water-equivalence of MAGIC-f polymer gel for {sup 60}Co and {sup 192}Ir clinical brachytherapy sources, through dose distributions simulated with PENELOPE Monte Carlo code. Methods: The real geometry of {sup 60} (BEBIG, modelo Co0.A86) and {sup 192}192Ir (Varian, model GammaMed Plus) clinical brachytherapy sources were modelled on PENELOPE Monte Carlo simulation code. The most probable emission lines of photons were used for both sources: 17 emission lines for {sup 192}Ir and 12 lines for {sup 60}. The dose distributions were obtained in a cubic water or gel homogeneous phantom (30 × 30 × 30 cm{sup 3}), with the source positioned in the middle of the phantom. In all cases the number of simulation showers remained constant at 10{sup 9} particles. A specific material for gel was constructed in PENELOPE using weight fraction components of MAGIC-f: wH = 0,1062, wC = 0,0751, wN = 0,0139, wO = 0,8021, wS = 2,58×10{sup −6} e wCu = 5,08 × 10{sup −6}. The voxel size in the dose distributions was 0.6 mm. Dose distribution maps on the longitudinal and radial direction through the centre of the source were used to analyse the water-equivalence of MAGIC-f. Results: For the {sup 60} source, the maximum diferences in relative doses obtained in the gel and water were 0,65% and 1,90%, for radial and longitudinal direction, respectively. For {sup 192}Ir, the maximum difereces in relative doses were 0,30% and 1,05%, for radial and longitudinal direction, respectively. The materials equivalence can also be verified through the effective atomic number and density of each material: Zef-MAGIC-f = 7,07 e .MAGIC-f = 1,060 g/cm{sup 3} and Zef-water = 7,22. Conclusion: The results showed that MAGIC-f is water equivalent, consequently being suitable to simulate soft tissue, for Cobalt and Iridium energies. Hence, gel can be used as a dosimeter in clinical applications. Further investigation to its use in a clinical protocol is needed.

  10. Comprehensive Evaluation of Toxoplasma gondii VEG and Neospora caninum LIV Genomes with Tachyzoite Stage Transcriptome and Proteome Defines Novel Transcript Features

    KAUST Repository

    Ramaprasad, Abhinay

    2015-04-13

    Toxoplasma gondii is an important protozoan parasite that infects all warm-blooded animals and causes opportunistic infections in immuno-compromised humans. Its closest relative, Neospora caninum, is an important veterinary pathogen that causes spontaneous abortion in livestock. Comparative genomics of these two closely related coccidians has been of particular interest to identify genes that contribute to varied host cell specificity and disease. Here, we describe a manual evaluation of these genomes based on strand-specific RNA sequencing and shotgun proteomics from the invasive tachyzoite stages of these two parasites. We have corrected predicted structures of over one third of the previously annotated gene models and have annotated untranslated regions (UTRs) in over half of the predicted protein-coding genes. We observe distinctly long UTRs in both the organisms, almost four times longer than other model eukaryotes. We have also identified a putative set of cis-natural antisense transcripts (cis-NATs) and long intergenic non-coding RNAs (lincRNAs). We have significantly improved the annotation quality in these genomes that would serve as a manually curated dataset for Toxoplasma and Neospora research communities.

  11. Safety and immunogenicity of a soluble native Neospora caninum tachyzoite-extract vaccine formulated with a soy lecithin/β-glucan adjuvant in pregnant cattle.

    Science.gov (United States)

    Mansilla, Florencia Celeste; Moore, Dadín Prando; Quintana, María Eugenia; Cardoso, Nancy; Hecker, Yanina Paola; Gual, Ignacio; Czepluch, Wenzel; Odeón, Anselmo Carlos; Capozzo, Alejandra Victoria

    2015-05-15

    The global economic impact of Neospora caninum infection in cattle herds has promoted the development of vaccines that can be safely used during pregnancy. The aim of this study was to evaluate the safety and immunogenicity of a vaccine formulated with the soluble fraction of tachyzoite's lysate and a soy-based aqueous adjuvant (sNcAg/AVEC), which was protective in the mouse model and induced strong IFN-γ responses and high avidity antibodies in non-pregnant cattle. Ten pregnant heifers were vaccinated twice during the first trimester of gestation and 8 remained unvaccinated. Anti-N. caninum immune responses were efficiently primed by vaccination, evidenced by a quick induction of IgM serum titers (7dpv) and a prompt switch to high avidity IgG shortly after infection (performed at 78 or 225 days of gestation; n=5 each); while naïve cattle elicited lower IgG titers, with a delayed kinetics. High systemic IFN-γ levels were induced after infection which did not interfere with pregnancy. No local or systemic adverse effects were recorded along the study. Calves were born in term and in good health conditions, showing that the sNcAg/AVEC vaccine was safe when applied to healthy heifers during the first trimester of gestation.

  12. Comprehensive evaluation of Toxoplasma gondii VEG and Neospora caninum LIV genomes with tachyzoite stage transcriptome and proteome defines novel transcript features.

    Science.gov (United States)

    Ramaprasad, Abhinay; Mourier, Tobias; Naeem, Raeece; Malas, Tareq B; Moussa, Ehab; Panigrahi, Aswini; Vermont, Sarah J; Otto, Thomas D; Wastling, Jonathan; Pain, Arnab

    2015-01-01

    Toxoplasma gondii is an important protozoan parasite that infects all warm-blooded animals and causes opportunistic infections in immuno-compromised humans. Its closest relative, Neospora caninum, is an important veterinary pathogen that causes spontaneous abortion in livestock. Comparative genomics of these two closely related coccidians has been of particular interest to identify genes that contribute to varied host cell specificity and disease. Here, we describe a manual evaluation of these genomes based on strand-specific RNA sequencing and shotgun proteomics from the invasive tachyzoite stages of these two parasites. We have corrected predicted structures of over one third of the previously annotated gene models and have annotated untranslated regions (UTRs) in over half of the predicted protein-coding genes. We observe distinctly long UTRs in both the organisms, almost four times longer than other model eukaryotes. We have also identified a putative set of cis-natural antisense transcripts (cis-NATs) and long intergenic non-coding RNAs (lincRNAs). We have significantly improved the annotation quality in these genomes that would serve as a manually curated dataset for Toxoplasma and Neospora research communities.

  13. Current status of food irradiation in the world. Trend in Asia

    Energy Technology Data Exchange (ETDEWEB)

    Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2002-11-01

    This review describes the current status of food irradiation in the world and particularly, its trends in Asia, based on the report of the economic scale investigation on the irradiation in United States and Japan (2001) and on the information of 12th International Meeting on Radiation Processing in France in 2001 and on personal communications. International Consultative Group on Food Irradiation promotes its activities of irradiation globally and 46 countries are affiliated. Food irradiation is allowed in 52 countries. In 1999, 257,000 t of food is irradiated in the world, of which 1/3 is due to spice. The facilities for the irradiation have such sources as {sup 60}Co and {sup 137}Cs {gamma}-rays, electron beam of <10 MeV and X-ray with <5 MeV. Detection methods of irradiated foods are summarized by the project of Analytical Detection Methods for Irradiation Treatment of Foods. The US is the most advanced country in the irradiation and, in Japan, only irradiation of potato is permitted. The detailed present status is also described of Bangladesh, China (the irradiation is most widely conducted in the world), India, Indonesia, Korea, Malaysia, Thailand and Vietnam. Recently Australia and New Zealand have started the irradiation. (K.H.)

  14. Effect of gamma irradiation combined with hot water treatment on the texture, pulp color and sensory quality of ''Nahng Glahng Wahn'' mangoes

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, M.; Jobin, M.; Beliveau, M.; Gagnon, M. (Canadian Irradiation Centre, Laval, PQ (Canada))

    1992-01-01

    Mangoes (Mangifera indica L.) from Thailand of the 'Nahng Glahng Wahn' variety were irradiated with a [sup 60] Co source at a dose of 0.63 kGy and a dose rate of 9.23 kGy/hr, with or without a hot water treatment prior to irradiation. The irradiation treatment had little effect on the texture and preserved the yellow color in the pulp. Test of sensory evaluation revealed that irradiated mango pulp was preferred for overall appearance, taste, texture and palatability. The appearance of whole irradiated mangoes was also preferred over that of the control mangoes. However, no significant differences were observed between irradiated and hot water dipped irradiated mangoes for all characteristics studied in mangoes pulp. The results showed that these treatments (hot water dip plus irradiation or irradiation alone) are useful and non-destructive methods to preserve consumer acceptability.

  15. On line high dose static position monitoring by ionization chamber detector for industrial gamma irradiators

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Ary A. [Universidade Estadual de Londrina-Depto de Fisica, Rodovia Celso Garcia Cid, km 38, 086051-990 Londrina (Brazil); Vieira, Jose M. [Instituto de Pesquisas Energeticas e Nucleares-IPEN/CNEN-SP, Prof. Lineu Prestes, 2242-Cidade Universitaria, 05508-900 Sao Paulo (Brazil); Hamada, Margarida M. [Instituto de Pesquisas Energeticas e Nucleares-IPEN/CNEN-SP, Prof. Lineu Prestes, 2242-Cidade Universitaria, 05508-900 Sao Paulo (Brazil)], E-mail: mmhamada@ipen.br

    2010-04-15

    A 1 cm{sup 3} cylindrical ionization chamber was developed to measure high doses on line during the sample irradiation in static position, in a {sup 60}Co industrial plant. The developed ionization chamber showed to be suitable for use as a dosimeter on line. A good linearity of the detector was found between the dose and the accumulated charge, independently of the different dose rates caused by absorbing materials.

  16. On line high dose static position monitoring by ionization chamber detector for industrial gamma irradiators.

    Science.gov (United States)

    Rodrigues, Ary A; Vieira, Jose M; Hamada, Margarida M

    2010-01-01

    A 1 cm(3) cylindrical ionization chamber was developed to measure high doses on line during the sample irradiation in static position, in a (60)Co industrial plant. The developed ionization chamber showed to be suitable for use as a dosimeter on line. A good linearity of the detector was found between the dose and the accumulated charge, independently of the different dose rates caused by absorbing materials.

  17. Results on photon and neutron irradiation of semitransparent amorphous-silicon sensors

    CERN Document Server

    Carabe, J; Ferrando, A; Fuentes, J; Gandia, J J; Josa-Mutuberria, I; Molinero, A; Oller, J C; Arce, P; Calvo, E; Figueroa, C F; García, N; Matorras, F; Rodrigo, T; Vila, I; Virto, A L; Fenyvesi, A; Molnár, J; Sohler, D

    2000-01-01

    Semitransparent amorphous-silicon sensors are basic elements for laser 2D position reconstruction in the CMS multipoint alignment link system. Some of the sensors have to work in a very hard radiation environment. Two different sensor types have been irradiated with /sup 60/Co photons (up to 100 kGy) and fast neutrons (up to 10/sup 15 / cm/sup -2/), and the subsequent change in their performance has been measured. (13 refs).

  18. Irradiation damage

    Energy Technology Data Exchange (ETDEWEB)

    Howe, L.M

    2000-07-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization.

  19. Application of the Cavity theory in the calibration of the powder TLD-100 for energies of {sup 60} Co, {sup 137} Cs, {sup 192} Ir and RX 50, 250 k Vp; Aplicacion de la Teoria de la Cavidad en la calibracion de polvo TLD-100 para energias de {sup 60} Co, {sup 137} Cs, {sup 192} Ir y RX 50, 250 kVp

    Energy Technology Data Exchange (ETDEWEB)

    Loaiza C, S.P. [UAEM, Programa de Maestria en Fisica Medica, 50180, Toluca, Estado de Mexico (Mexico); Alvarez R, J.T. [ININ, 52750, Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: sandraplc_04@yahoo.com.mx

    2006-07-01

    A powder lot TLD-100 (LiF:Mg,Ti) in absorbed dose terms in water D{sub w} for the following radiation sources: {sup 60} Co, {sup 137} Cs and RX 50 and 250 k Vp is calibrated; to continuation is made a lineal interpolation of the TLD response in function of the effective energy of the sources to calibrate a source of {sup 192} Ir. The calibration of those fields in D{sub w} are carried out with aid of the Bragg-Gray cavity theory, the one which finds implicit in the following protocols: IAEA-TRS 398 for the {sup 60} Co and the AAPM TG61 for X Rays of 50 and 250 k Vp. Additionally the AAPM protocol TG43 to determine the D{sub w} in function of the kerma intensity S{sub k} in the case of the {sup 137} Cs is used. The calibration curves for the response of the TLD-100 R{sub TLD} vs D{sub w}, corresponding to each one of the sources already mentioned are constructed. The R{sub TLD} vs D{sub w} by least heavy square by means of a second order polynomial that corrects the supralineality of the response is adjusted. The curves are validated by lack of LOF adjustment and by the Anderson Darling normality test. Later the factors of sensitivity (F{sub s}) for the sources of {sup 192} Ir: Micro Selectron and Vari Source are interpolated, used respectively in the A and B hospitals for treatments of brachytherapy of high dose rate (HDR), the expanded uncertainties associated to the D{sub w} and F{sub s} are also determined. Finally, an acrylic phantom and a couple of capsules are already sent to the hospitals mentioned, to verify a nominal D{sub w} of 2 Gy, in a case an underestimate in 5.5% in the imparted D{sub w} and in other an overestimation in a range of -1.5 to -8.0% was obtained. The obtained results in this work establish the bases for the development of a national dosimetric quality control program for brachytherapy of HDR with sources of {sup 192} Ir. (Author)

  20. 60Co-γ射线照射大鼠损伤作用中硫辛酸对谷胱甘肽的调节与再生%Modulation of lipoic acid and regeneration of glutathion in rats injured by radiation with 60Co-γ ray

    Institute of Scientific and Technical Information of China (English)

    赵康涛; 海春旭; 梁欣; 张晓迪; 秦绪军; 刘瑞; 陈宏莉; 谷小刚

    2003-01-01

    目的: 以60Co-γ射线照射大鼠损伤为模型,研究硫辛酸对大鼠谷胱甘肽(glutathione, GSH)的调节和再生作用. 方法: 二级SD大鼠40只,雌雄各半,随机分为4组,为阴性对照组、阳性对照组、低剂量组(硫辛酸0.2 g*L-1),高剂量组(硫辛酸0.4 g*L-1),60Co-γ射线照射剂量为4 Gy. 对阳性组、低剂量组、高剂量组动物进行照射后,低剂量组和高剂量组动物分别给予硫辛酸油溶液灌胃(5 mL*kg-1). 阴性组和阳性组分别给予处理精炼油灌胃作为对照;连续灌胃给药2 d后断头处死,收集全血静置、析出血清,用荧光分光法及分光光度法测定GSH,MDA和谷胱甘肽过氧化物酶(glutathione peroxidase, GPx)等指标. 结果: 辐射损伤引起还原型谷胱甘肽含量的降低而氧化型谷胱甘肽(oxidized glutathione, GSSG)的含量增高(P<0.05);补充了硫辛酸能增加还原型谷胱甘肽的含量,且随着给药剂量的增加而升高(P<0.05),GSSG则呈相反趋势;硫辛酸能降低辐射损伤造成的GPx的活性的应激性增高(P<0.05). 结论: 硫辛酸对辐射损伤造成的氧化损伤具有保护作用,并能调节抗氧化剂GSH的含量,提高机体的抗氧化能力.

  1. Thermoluminescence properties of irradiated chickpea and corn

    Energy Technology Data Exchange (ETDEWEB)

    Necmeddin Yazici, A. [University of Gaziantep, Department of Engineering, Physics, 27310 Gaziantep (Turkey)], E-mail: yazici@gantep.edu.tr; Bedir, Metin; Bozkurt, Halil [University of Gaziantep, Department of Engineering, Physics, 27310 Gaziantep (Turkey); Bozkurt, Hueseyin [University of Gaziantep, Department of Food Engineering, 27310 Gaziantep (Turkey)

    2008-02-15

    A study was carried out to establish a detection method for irradiated chickpea and corn by thermoluminescence (TL) method. The leguminous were packed in polyethylene bags and then the packets were irradiated at room temperature at different doses by {sup 60}Co gamma source at 1, 4, 8 and 10 kGy. Minerals extracted from the leguminous were deposited onto a clean aluminum disc and TL intensities of the minerals were measured by TL. It was observed that the extracted samples from both leguminous exhibit good TL Intensity and the TL intensity of glow curves of them increased proportionally to irradiation doses. The TL glow curve of both irradiated leguminous presents a single broad peak below 400 degC. The TL trapping parameters glow peaks were estimated by the additive dose (AD), T{sub m}(E{sub a})-T{sub stop} and computerized glow curve deconvolution (CGCD) methods. The fading characteristics of glow curves were also recorded up to 6 months.

  2. Effects of hadron irradiation on scintillating fibers

    Energy Technology Data Exchange (ETDEWEB)

    Atac, M. (Univ. of California, Los Angeles, CA (United States) Fermi National Accelerator Lab., Batavia, IL (United States)); Buchanan, C.; Chrisman, D.; Cline, D.; Kolonko, J.; Kubic, J.; Park, J. (Univ. of California, Los Angeles, CA (United States)); Baumbaugh, A.; Binkley, M.; Bross, A.D.; Finley, D.; Elias, J.; Foster, G.W.; Kephart, R.; Kephart, R.; Kim, C.; Park, H.; Pla-Dalmau, A.; Rivetta, C.; Tkaczyk, S.; Wagner, R. (Fermi National Accelerator Lab., Batavia, IL (United States)); Chung, M.; Goldberg, H.; Jeskik, R.; Margulies, S.; Mendez, H.; Solomon, J.; Vaca, F. (Univ. of Illinois, Chicago, IL (United States)); Kelley, C. (Massachusetts College of Pharmacy and Allied Health Sciences, Boston, MA (United States)); Baumbaugh, B.; Bishop, J.; Biswas, N.; Cason, N.; Jacques, J.; Kehoe, R.; Kelly, M.; Kenney, V.; LoSecco, J.; Ruchti, R.; Shephard, W.; Warchol, J.; Wayne, M.; Marchant, J.; Mountain, R.J. (Univ. of Notre Dame, IN (United States)); Davis, D.; Vandergriff, D. (O

    1993-08-01

    Trackers based on scintillating-fiber technology are being considered by the Solenoidal Detector Collaboration at SSC and the D[phi] collaboration at Fermilab. An important issue is the effect of the radiation existing in the detector cores on fiber properties. Most studies of radiation damage in scintillators have irradiated small bulk samples rather than fibers, and have used X-rays, [sup 60]Co gammas, or electron beams, often at accelerated rates. The authors have irradiated some 600 fibers in the Fermilab Tevatron C[phi] area, thereby obtaining a hadronic irradiation at realistic rates. Four-meter-long samples of ten Bicron polystyrene-based fiber types, maintained in air, dry nitrogen, argon, and vacuum atmospheres within stainless-steel tubes, were irradiated for seven weeks at various distances from the accelerator beam pipes. Maximum doses, measured by thermoluminescence detectors, were about 80 Krad. Fiber properties, particularly light yield and attenuation length, have been measured over a one-year period. A description of the work together with the results is presented. At the doses achieved, corresponding to a few years of actual fiber-tracking detector operation, little degradation is observed. In addition, recovery after several days' exposure to air has been noted. Properties of unirradiated samples kept in darkness show no changes after one year.

  3. γ-ray irradiation effect on siloxane foam containning phenyl

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The 60Co γ radiation effect on spherical open-porous polymethylphenylvinyl siloxane foam was studied in different atmospheres at room temperature. The physical and chemical behaviors of unirradiated and irradiated materials were studied by SEM, FTIR, TG (thermal gravity analysis), GC/MS(gas chromatography and mass spec troscopy), etc. The present results indicate that the yields of gas products increase linearly with the dose increasing. Furthermore, some changes in material's microscopic form, composition, structure and mechanical property were observed, but the maxi mum thermal decomposition temperature of the sample alters little and the dose gives no effect on it.

  4. Effect of melatonin and time of administration on irradiation-induced damage to rat testes

    Directory of Open Access Journals (Sweden)

    G. Take

    2009-07-01

    Full Text Available The effect of ionizing irradiation on testes and the protective effects of melatonin were investigated by immunohistochemical and electron microscopic methods. Eighty-two adult male Wistar rats were divided into 10 groups. The rats in the irradiated groups were exposed to a sublethal irradiation dose of 8 Gy, either to the total body or abdominopelvic region using a 60Co source at a focus of 80 cm away from the skin in the morning or evening together with vehicle (20% ethanol or melatonin administered 24 h before (10 mg/kg, immediately before (20 mg/kg and 24 h after irradiation (10 mg/kg, all ip. Caspace-3 immunoreactivity was increased in the irradiated group compared to control (P < 0.05. Melatonin-treated groups showed less apoptosis as indicated by a considerable decrease in caspace-3 immunoreactivity (P < 0.05. Electron microscopic examination showed that all spermatogenic cells, especially primary spermatocytes, displayed prominent degeneration in the groups submitted to total body and abdominopelvic irradiation. However, melatonin administration considerably inhibited these degenerative changes, especially in rats who received abdominopelvic irradiation. Total body and abdominopelvic irradiation induced identical apoptosis and testicular damage. Chronobiological assessment revealed that biologic rhythm does not alter the inductive effect of irradiation. These data indicate that melatonin protects against total body and abdominopelvic irradiation. Melatonin was more effective in the evening abdominopelvic irradiation and melatonin-treated group than in the total body irradiation and melatonin-treated group.

  5. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Webb, T.

    1986-01-01

    The proposed use of gamma radiation from cobalt 60 and cesium 137 for food irradiation in the United Kingdom is discussed, with particular reference to the possible dangers and disadvantages to the safety and wholesomeness of the food.

  6. Metacyclic promastigotes of Leishmania amazonensis selection using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bonetti, Franco C.; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Centro de Biologia Molecular]. E-mail: fbonetti@usp.br; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo, SP (Brazil). Lab. de Protozoologia

    2005-07-01

    Leishmania spp. causes a spectrum of human diseases, ranging from self-healing skin lesions to severe and lethal visceral disease. In previous work we demonstrated that the protein and nucleic acid metabolism and oxidative respiration were severely affected by irradiation, in a dose response way, but a small but representative fractions are relatively radio resistant, surviving after 800 Gy of {sup 60}Co irradiation. The best explanation could be a selection of metacyclic promastigotes. In these forms, the G0 state allows the adequate correction of DNA repair after the irradiation insult. In this work, we are looking for the ideal radiation dose to select the higher proportion of metacyclic forms of L.. (L.) amazonensis in culture. Parasites were grown in RPMI 1640 medium, plus 20% fetal calf serum, than they were irradiated with different doses ranging between 25 and 400 Gy. Parasites irradiated at 400 Gy infected, proportionally, more cells than parasites irradiated at other doses. To confirm this metacyclogenesis, a complement lysis assay was performed with 5, 10 and 20% of male guinea pig blood serum at 20 deg C for 3 hours, and parasites counted. Guinea pig serum a 10% promotes more lysis, with 200 Gy irradiated parasites being less affected, probably due to metacyclic selection. These preliminary results suggests that the ionizing radiation, specially between 200 and 400 Gy, could be a alternative tool for the selection of metacyclic forms of Leishmania amazonensis in culture. (a0011uth.

  7. Identification of irradiated refrigerated pork with the DNA comet assay

    Science.gov (United States)

    Araújo, M. M.; Marin-Huachaca, N. S.; Mancini-Filho, J.; Delincée, H.; Villavicencio, A. L. C. H.

    2004-09-01

    Food irradiation can contribute to a safer and more plentiful food supply by inactivating pathogens, eradicating pests and by extending shelf-life. Particularly in the case of pork meat, this process could be a useful way to inactivate harmful parasites such as Trichinella and Taenia solium. Ionizing radiation causes damage to the DNA of the cells (e.g. strand breaks), which can be used to detect irradiated food. Microelectrophoresis of single cells (``Comet Assay'') is a simple and rapid test for DNA damage and can be used over a wide dose range and for a variety of products. Refrigerated pork meat was irradiated with a 60Co source, Gammacell 220 (A.E.C.L.) installed in IPEN (Sa~o Paulo, Brazil). The doses given were 0, 1.5, 3.0 and 4.5kGy for refrigerated samples. Immediately after irradiation the samples were returned to the refrigerator (6°C). Samples were kept in the refrigerator after irradiation. Pork meat was analyzed 1, 8 and 10 days after irradiation using the DNA ``Comet Assay''. This method showed to be an inexpensive and rapid technique for qualitative detection of irradiation treatment.

  8. Identification of irradiated refrigerated pork with the DNA comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, M.M. E-mail: villavic@net.ipen.br; Marin-Huachaca, N.S.; Mancini-Filho, J. E-mail: jmancini@usp.br; Delincee, H.; Villavicencio, A.L.C.H. E-mail: henry.delincee@bfe.uni-karlsruhe.de

    2004-10-01

    Food irradiation can contribute to a safer and more plentiful food supply by inactivating pathogens, eradicating pests and by extending shelf-life. Particularly in the case of pork meat, this process could be a useful way to inactivate harmful parasites such as Trichinella and Taenia solium. Ionizing radiation causes damage to the DNA of the cells (e.g. strand breaks), which can be used to detect irradiated food. Microelectrophoresis of single cells ('Comet Assay') is a simple and rapid test for DNA damage and can be used over a wide dose range and for a variety of products. Refrigerated pork meat was irradiated with a {sup 60}Co source, Gammacell 220 (A.E.C.L.) installed in IPEN (Sao Paulo, Brazil). The doses given were 0, 1.5, 3.0 and 4.5 kGy for refrigerated samples. Immediately after irradiation the samples were returned to the refrigerator (6 deg. C). Samples were kept in the refrigerator after irradiation. Pork meat was analyzed 1, 8 and 10 days after irradiation using the DNA 'Comet Assay'. This method showed to be an inexpensive and rapid technique for qualitative detection of irradiation treatment.

  9. Enact of Glutathione(GSH/GSSG) Contents of Fermented Ginseng on the {gamma}-irradiated Liver of Mice

    Energy Technology Data Exchange (ETDEWEB)

    Ko, In Ho [Dept. of Radiology Technology, Jeju Halla College, Jeju (Korea, Republic of)

    2006-03-15

    The radioprotective effects of white and fermented ginseng on liver damage induced by {sup 60}Co {gamma}-ray were investigated. To one group of ICR male mice were given white(150 mg/kg/day for 7 days, orally) and fermented ginseng(150 mg/kg/day for 7 days, orally) before {sup 60}Co {gamma}--ray irradiation. To another group were irradiated by 5 Gy(1.01 Gy/min) dose of {sup 60}Co {gamma}--ray. Contrast group were given with saline(0.1 mL). The levels of reduced(GSH) and oxidized(GSSG) glutathione in liver tissue were measured. In the fermented(150 mg/kg) and white ginseng(150 mg/kg) groups than irradiation group, the GSH levels were significantly increased, but the GSSG levels were significantly decreased. The ratio of GSSG/total GSH was significantly decreased in the fermented(150 mg/kg) and white ginseng(150 mg/kg) groups than irradiation group. In the fermented(150 mg/kg) groups than white ginseng(150 mg/kg) groups the GSH levels were significantly increased. The radioprotective effects of fermented(150 mg/kg) groups than white ginseng(150 mg/kg) groups were increased.

  10. [Food irradiation].

    Science.gov (United States)

    Migdał, W

    1995-01-01

    A worldwide standard on food irradiation was adopted in 1983 by Codex Alimentarius Commission of the Joint Food Standard Programme of the Food and Agriculture Organization (FAO) of the United Nations and the World Health Organization (WHO). As a result, 41 countries have approved the use of irradiation for treating one or more food items and the number is increasing. Generally, irradiation is used to: food loses, food spoilage, disinfestation, safety and hygiene. The number of countries which use irradiation for processing food for commercial purposes has been increasing steadily from 19 in 1987 to 33 today. In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in Institute of Nuclear Chemistry and Technology. The plant is equipped with a small research accelerator Pilot (19MeV, 1 kW) and an industrial unit Elektronika (10MeV, 10 kW). On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permission for irradiation for: spices, garlic, onions, mushrooms, potatoes, dry mushrooms and vegetables.

  11. Kinetics and time dependence of the differential agglutination of acetone [AC]- and formalin [HS]-fixed Toxoplasma tachyzoites by serum of mice with experimental toxoplasmosis.

    Science.gov (United States)

    Ali, Nehad Mahmoud; Habib, Khaled Sayed Mohamed

    2012-04-01

    Researches to specify a serologic diagnostic test capable of determining the stage of toxoplasmosis, whether recent or latent, have been hampered by lack of knowing the real time of infection. Studying the precise kinetics of the differential agglutination of acetone [AC]-fixed versus that of formalin [HS]-fixed tachyzoites (differential agglutination test or AC/HS test) by sera of mice during the course of toxoplasmosis and assessment of its value in the differentiation between recent and latent infections in mice were the aims of the present work. Experimental toxoplasmosis was induced in mice, sera were collected sequentially and AC/HS test, FAST-ELISA to determine levels of IgM and IgG and microscopic examination of brain for Toxoplasma cysts were done. Both AC and HS specific patterns in the AC/HS test were noted to be dependent on the time from the onset of infection. Acute patterns of the AC/HS test were observed early in infection till before the appearance of brain cysts. Non-acute patterns were obtained late on 28th day post infection coinciding with the disappearance of IgM, persistence of IgG and presence of cysts in brains. The AC antibody was high in the recent phase of infection, and then it declined to be replaced by high sustained level of HS antibody late in infection. In conclusion, in the presence of both IgM and IgG, the appearance of either equivocal pattern or the non-acute pattern in the AC/HS test is significant in ruling out acute infection in mice.

  12. In vitro cultivation of Hammondia heydorni: Generation of tachyzoites, stage conversion into bradyzoites, and evaluation of serologic cross-reaction with Neospora caninum.

    Science.gov (United States)

    Gondim, L F P; Meyer, J; Peters, M; Rezende-Gondim, M M; Vrhovec, M G; Pantchev, N; Bauer, C; Conraths, F J; Schares, G

    2015-06-15

    Hammondia heydorni was in vitro isolated from oocysts shed by three dogs using a finite cell line from embryonal bovine heart (KH-R). The oocysts were purified and suspended in 2% potassium dichromate or 2% sulphuric acid for sporulation for 2-5 days at room temperature. The parasites were confirmed as H. heydorni by PCR using specific primers (JS4/JS5) and by negative reaction for Neospora caninum employing the primers Np6+/Np21+. H. heydorni sporulated oocysts (1 × 10(6)) from each dog were initially treated with sodium hypochlorite. For excystation of sporozoites, oocysts from one dog were lysed by ultrasound followed by incubation with 0.75% taurocholate. Excystation of sporozoites from the other two dogs was achieved by oocyst fragmentation with glass beads with no further chemical treatment. Tachyzoites were clearly seen in the cultures at three days post inoculation (dpi). Bradyzoite conversion and cyst formation were evaluated at different time points by using a polyclonal rabbit serum against a bradyzoite-specific antigen (anti-BAG1), and a rat monoclonal antibody (mAbCC2) against a cyst wall protein. Bradyzoites were firstly detected at 7 dpi. Between 18 and 21 dpi most of cultured parasites consisted of encysted bradyzoites. The H. heydorni cysts increased in size during cultivation and reached a length of up to 135 μm. The parasite was maintained in the bovine heart cells up to 4.5months. Sera from mice and sheep experimentally infected with H. heydorni oocysts reacted with H. heydorni by IFAT, but did not cross-react with N. caninum antigens using IFAT or immunoblot. These findings suggest that serological cross-reactivity between H. heydorni and N. caninum seems to be of minor importance.

  13. Thermal analysis of polypropylene modified by gamma irradiation composites under outdoor conditions

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, Luiz G.H.; Oliani, Washington L.; Lugao, Ademar B.; Parra, Duclerc F., E-mail: dfparra@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This work reports the influence of the clay in the degradation process of the HMSPP.The polypropylene (PP) was irradiated under acetylene atmosphere in gamma irradiation source ({sup 60}Co) to obtain the HMSPP (high melt strength polypropylene). Composites of HMSPP were processed in twin-screw extruder with clay Cloisite 20A and Maleic Anhydride (PP-g-MA) as coupling agent. The obtained composites were exposed under outdoor conditions for 6 months. The ageing effects were characterized by Differential Scanning Calorimetry (DSC), Thermogravimetry Analysis (TGA). Chemical oxidation was evaluated by Carbonyl Index (IC) through infrared Spectroscopy (FT-IR). The results showed correlation between carbonyl index and ageing time. (author)

  14. Effects of 3 MeV proton irradiation on the mechanical properties of polyimide films

    Science.gov (United States)

    Hill, David J. T.; Hopewell, Jefferson L.

    1996-11-01

    The effects of 3 MeV proton irradiation on the elongation to break, fracture energy and Young's Modulus have been investigated for films of Kapton and Ultem over the dose range 0-75 MGy at ambient temperature. The results have been compared with those reported by other workers for irradiation by 60Co gamma rays and 2 MeV electron beams under similar conditions, and little difference was found between the damage to the mechanical properties of the films induced by these three beam types.

  15. Effect of {sup 60}Co gamma radiation on the levels of phenolic compounds from crude extracts of bark of Spondias luta L

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo H.F.; Silva, Hianna A.M.F.; Melo, Mychely S., E-mail: santosghf@hotmail.com, E-mail: hiannaamfs@gmail.com, E-mail: mychely.melo@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Silva, Edvane B., E-mail: edvborges@yahoo.com [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil). Centro Academinco de Vitoria

    2013-07-01

    Spondias luta L. (Anacardiaceae), popularly known as cajazeira, is a plant widespread in several regions of Brazil, famous for containing phenolic compounds, which are responsible for your characteristic astringent. Ionizing radiations have the ability to cross the material, ionizing atoms and molecules, causing changes in atoms and molecules important. It is known ionizing radiation promotes quantitative and qualitative changes in plant materials, increasing, decreasing or inactivating secondary substances. The objective of this work was to evaluate the effect of gamma radiation as a modifier of the activity of the phenolic compounds of the bark extract of S. luta L. Methods: For the dosage of phenol extracts (control, irradiated with 5 kGy, 10 kGy, 15 kGy and 20 kGy) were diluted in methanol to a final concentration of 200 mg / L. In test tubes were added 50 μL of extract plus 1 ml of distilled water and 500 μl of Folin (diluted 1:10). After 10 minutes in a dark chamber was added 2.5 ml of calcium carbonate to 20% and the content of the tube was homogenized. After 20 minutes was performed with a spectrophotometer at 735 nm. The assay was performed in triplicate and calculated from a standard curve solution of gallic acid and expressed in μEAG (GAE/mg extract). Results: The control extracts, irradiated to 5 kGy, 10 kGy, 15 kGy and 20 kGy, had, respectively, 6.25, 6.70, 6.25, 6.85, 6.45 μEAG/mg of extract. Conclusion: The results showed no significant change in the amount of phenolic compounds, showing that these compounds are radioresistant extract these doses. (author)

  16. The influence of {sup 60}Co gamma radiation on the action of phenolic compounds Anadenanthera colubrina (Vell.) Brenan in the microbiological control of crude extracts

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo Henrique F. dos; Silva, Edvane B. da, E-mail: santosghf@hotmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR); Sena, Kesia Xisto da Fonseca R. de; Silva, Bruna L., E-mail: kxfrs@bol.com.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Antibioticos; Lima, Claudia S. de A., E-mail: claudia.salima@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    2009-07-01

    Anadenanthera colubrina (Vell.) Brenan, known popularly as angico is a tree founded in northeastern of Brazil, and has great economic and ecological interest. These trees are characterized by high levels of tannins. To evaluate the influence of gamma radiation in plant extracts of barks and leaves of angico, we got extracts of barks and leaves in 70% ethanol, which was filtered and evaporated until dryness. It were classified in four groups (non-irradiated, 5; 7.5 and 10 kGy). The total phenols were quantified by Folin-Ciocalteau method, and the tannins, using the precipitation of casein. The antimicrobial activity of extracts was observed using the paper disk diffusion methods against Gram-positive, Gram-negative, acid-alcohol-resistant bacteria: and yeasts. The halos greater than 10 mm were considered actives. It was also performed the Minimal Inhibitory Concentration (MIC) using Gram positive and alcohol-acid resistant bacteria. The results showed that tannins of A. colubrina, were 52 to 57% of total phenols, and leaves, 58 to 60%. The percentage of total phenols and tannins in the barks and leaves of A. colubrina have not statistically significant change when compared with the irradiated control. These results suggest that A. colubrina has antimicrobial activity against the Gram-positive and alcohol-acid -resistant bacteria, confirmed by MIC. The extracts of leaves it was additionally actives against the Gram-negative and against the yeast C. albicans. These results show that the gamma radiation has not influence about the antimicrobial activity of crude extracts of barks and leaves of A. colubrina. (author)

  17. Effect of gamma irradiation on microbial load and sensory characteristics of aniseed (Pimpinella anisum).

    Science.gov (United States)

    Al-Bachir, M

    2007-07-01

    Seeds of anise (Pimpinella anisum) were exposed to doses of 0, 5, 10, 15 and 20kGy in a (60)Co package irradiator. Irradiated and unirradiated samples were stored at room temperature. Microbial populations on seeds, total and inorganic soluble solids in water extract and sensory properties of the latter were evaluated after 0, 6 and 12 months of storage. Results indicated that gamma irradiation reduced the aerobic plate counts of aniseed. Immediately after irradiation, the total soluble solids in an extract of irradiated seeds were greater than those of unirradiated ones. The total soluble solids in an extract of irradiated and un-irradiated seeds increased after 6 and 12 months of storage. There were no significant differences (p>0.05) in inorganic soluble solids between the water extract of irradiated and unirradiated aniseeds. Sensory evaluation indicated that gamma irradiation improved sensory characteristics of aniseed water extract tested immediately after irradiation; however, after 12 months of storage, no significant differences (p>0.05) were found in color, taste or flavor between extract of irradiated and unirradiated seeds.

  18. Steroidogenesis in the testes and the adrenals of adult male rats after. gamma. -irradiation in utero at late pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Keiko; Takahashi, Masakazu; Ishii-Ohba, Hiroko; Ikeda, Kiyomi; Inano, Hiroshi (National Inst. of Radiological Sciences, Chiba (Japan))

    1990-02-01

    Pregnant rats were irradiated with 2.1Gy {gamma}-ray of {sup 60}Co at day 20 of gestation. Seventy days after birth, the body weight of the fetally irradiated male pups was significantly lower than the control. The testes, ventral prostates and seminal vesicles were atrophied by irradiation, whereas no decreased weight of the adrenals was observed. Histological examination of the testes of the irradiated rats revealed a complete disappearance of germinal cells. Sertoli cells and Leydig cells appeared normal, and no apparent histological difference was observed in the adrenals between the control and the irradiated rats. Examination of steroidgenesis in testes and adrenals led to the conclusion that irreversible damage was induced in spermatogenesis and androgen production by the fetal irradiation, whereas corticoidogenesis was not affected. (author).

  19. 60钴全身照射后自体骨髓移植的动物实验%Autografts of Bone Marrow in Dogs after Total Body Irradiation with 60Co

    Institute of Scientific and Technical Information of China (English)

    Wang Yaoping

    1982-01-01

    @@ 我们于1978年10月至1979年5月,对60钴全身照射后的动物作自体骨髓移植实验,目的是观察:(1)60钴全身照射的抑制作用及毒性反应; (2)自体骨髓移植对60钴全身照射后的动物的保护作用.现将实验工作总结于下.

  20. Dosimetry of an animal irradiation system

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Nelson M.; Funari, Ana P.; Miranda, Jurandir T.; Napolitano, Celia M.; Goncalves, Josemary A.C.; Bueno, Carmen C.; Mathor, Monica B., E-mail: nelsonnininho@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Radiation therapy uses ionizing radiation for cancer treatment, but its effectiveness may be limited by the consequent appearance of radiodermatitis. This problem may present several degrees: the highest among them is radionecrosis. Therefore, a model of study for the animal irradiation system (AIS) was built, generating radionecrosis on rat backs. The AIS is comprised by: a) a shield between the {sup 60}Co irradiator metallic guide and the animal immobilizer (AI), with holes exposing the rat skin; b) a shield on the AI posterior part and (c) the AIS angle. The doses were measured with alanine pellets in seven positions (two external and five internal) and different heights, in axial planes along the AI, and irradiated with 85 Gy. The similarity in the geometry of the AIs made it possible to relate the doses of positions 1-7 with the same height among the AISs. The AISs equidistance to the source allowed simultaneous animal exposure. Minimizing the shielding and maximizing the angles among the AISs provided average doses almost identical in position 1. A small variation among the mean doses for each of the AISs enabled to replace them by the average doses of the three AISs at position 1. Shields allowed the attenuation of the uncertainties in the alanine pellet in the AI, reduction of the exposure time without compromising rat security and the rise of the dose in measurement positions 1 and 2. The maximization of the angles among the AISs reduced the shielding secondary radiation contribution. (author)

  1. Thermogravimetry of irradiated human costal cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Martinho Junior, Antonio C.; Machado, Luci D.B.; Dias, Djalma B.; Mathor, Monica B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: antonio_carlos_martinho@msn.com; lmachado@ipen.br; dbdias@ipen.br; mathor@ipen.br; Herson, Marisa R. [Universidade de Sao Paulo, SP (Brazil). Hospital das Clinicas. Banco de Tecidos do Instituto Central]. E-mail: marisah@vifm.org; Meumann, Nilton F.; Pasqualucci, Carlos Augusto G. [Universidade de Sao Paulo, SP (Brazil). Faculdade de Medicina. Servico de Verificacao de Obitos]. E-mail: svoc@usp.br

    2007-07-01

    Costal cartilage has been sterilized with gamma radiation using {sup 60}Co sources at two different doses, 25 kGy and 50 kGy, for storage in tissue banks. Samples of costal cartilage were deep-freezing as method of preservation. Thermogravimetry (Shimadzu TGA-50) was used to verify the water release of costal cartilage before and after irradiation. The TG tests were carried out at heating rate of 10 deg C/min from room temperature to 600 deg C under a flow rate of 50 mL/min of compressed air. Samples of costal cartilage were divided in 2 parts. One part of them was kept as reference material; the other part was irradiated. This procedure assures better homogeneity of the sample and reproducibility of the experimental results. The obtained data have shown that the TG curves have the same pattern, independently of the sample. Non-irradiated samples showed great variability of thermogravimetric curves among different donors and for the same donor. Further experimental work is being carried out on human cartilage preserved in glycerol in high concentration (> 98%) to compare with those deep freezing. (author)

  2. Immunological assessment of mice hyperimmunized with native and Cobalt-60-irradiated Bothrops venoms

    Directory of Open Access Journals (Sweden)

    R. S. Ferreira Junior

    2005-12-01

    Full Text Available ELISA was used to evaluate, accompany, and compare the humoral immune response of Swiss mice during hyperimmunization with native and Cobalt-60-irradiated (60Co venoms of Bothrops jararaca, Bothrops jararacussu and Bothrops moojeni. Potency and neutralization were evaluated by in vitro challenges. After hyperimmunization, immunity was observed by in vivo challenge, and the side effects were assessed. The animals immunization with one LD50 of each venom occurred on days 1, 15, 21, 30, and 45, when blood samples were collected; challenges happened on the 60th day. Results showed that ELISA was efficient in evaluating, accompanying and comparing mouse immune response during hyperimmunization. Serum titers produced with natural venom were similar to those produced with irradiated venom. Immunogenic capacity was maintained after 60Co-irradiation. The sera produced with native venom showed neutralizing potency and capacity similar to those of the sera produced with irradiated venom. All antibodies were able to neutralize five LD50 from these venoms. Clinical alterations were minimum during hyperimmunization with irradiated venom, however, necrosis and death occurred in animals inoculated with native venom.

  3. GZP型60Co源剂量学参数的蒙特卡洛模拟%A Monte Carlo-based dosimetric study of the GZP 60Co source

    Institute of Scientific and Technical Information of China (English)

    王先良; 袁珂; 唐斌; 康盛伟; 黎杰; 肖明勇; 李晓兰; 李林涛; 王培

    2016-01-01

    目的 GZP型60Co源高剂量率后装机在临床中已有应用,模拟计算GZP型60Co源的剂量学参数.方法 使用EGSnrc蒙特卡洛软件模拟计算已知的BEBIG60Co源(Co0.A86)剂量学参数,与其结果进行对比,验证方法的可行性.对GZP型高剂量率后装机60Co源进行建模,用同样方法模拟计算GZP型60Co源剂量学参数.结果 对BEBIG 60Co源,结果与标准数据吻合很好,单位活度空气比释动能强度SK/A相差0.2%,剂量率常数∧相差1.0%,径向剂量函数gL(r)和各向异性函数F(r,θ)曲线吻合.计算得到的GZP型60Co源(1、2)号通道的SK/A和∧分别是3.011×10-7 cGycm2h-1Bq-1和1.118 cGyh-1U-1,GZP (3)号通道60Co源的SK/A和∧分别是3.002× 10-7 cGycm2h-1Bq-1和1.110 cGyh-1U-1,gL(r)、F(r,θ)和水模中单位空气比释动能强度的剂量率参照AAPM推荐列出.结论 研究结果可用于GZP型60Co源的计划系统中,也可以作为GZP型60Co源的质量控制.%Objective To simulate and calculate the dosimetric parameters of the GZP 60Co source that has been clinically used in high-dose-rate brachytherapy.Methods The EGSnrc Monte Carlo software was used to simulate and calculate the dosimetric parameters of a well known BEBIG 60Co source (Co0.A86).The results were compared with the actual parameters to verify the feasibility of this method.A Monte Carlo model of the GZP 60Co source for high-dose-rate brachytherapy was established to simulate and calculate its dosimetric parameters in the same way.Results For the BEBIG 60Co source,the resuhs were well accorded with the standard.The air-kerma strength per unit activity (SK/A) and dose rate constant (∧)deviated from the standard by 0.2% and 1.0%,respectively.The curves of the radial dose function gL(r) and the anisotropy function F (r,θ) fit well.For the GZP 60Co source,the SK/A and ∧values were calculated as 3.011 × 10-7 cGycm2h-1Bq-1 and 1.118 cGyh-1 U-1 in channel l&2 and 3.002× 10-7 cGycm2h-1 Bq-1 and 1.110 cGyh-1U

  4. Effect of molecular weight reduction by gamma irradiation on chitosan film properties

    Energy Technology Data Exchange (ETDEWEB)

    García, Mario A., E-mail: marioifal@gmail.com [Pharmacy and Food Institute, University of Havana, St. 222 No. 2317, ZC 13600 Havana (Cuba); Pérez, Liliam [Pharmacy and Food Institute, University of Havana, St. 222 No. 2317, ZC 13600 Havana (Cuba); Paz, Nilia de la [Drugs Research and Development Center, Ave. 26 No. 1605, Havana (Cuba); González, Juan [Food Industry Research Institute, Carretera al Guatao km 3 1/2, Havana, CP 19200 (Cuba); Rapado, Manuel [Radiobiology Department, Center for Technological Applications and Nuclear Development, St. 30 No. 502, Playa, Havana (Cuba); Casariego, Alicia [Pharmacy and Food Institute, University of Havana, St. 222 No. 2317, ZC 13600 Havana (Cuba)

    2015-10-01

    The present work aimed the influence of molecular weight (MW) reduction by irradiation with {sup 60}Co and polymer concentration on some physical properties of chitosan films. Irradiation of chitosan with a MW of 275.221 kDa and 74.74% of deacetylation degree was performed using a {sup 60}Co source to provide doses of 5, 10, 20 and 50 kGy to obtain chitosans with molecular weights of 247.847, 221.563, 126.469 and 77.063 kDa, respectively. Films were prepared via the solution casting method. Film-forming solutions (FFS) of chitosan irradiated or not, were prepared at 1.5 and 2% (w/v) in a solution of lactic acid at 1% (v/v) and 0.1% (v/v) of Tween 80. The FFS were poured into glass plates of 400 cm{sup 2} and dried at 60 °C during 10 h without airflow. The decrease of MW and increase of chitosan concentration increased the tensil strength and water vapor permeability while decreased the elongation at break of the films. The chitosan MW did not significantly influence (p > 0.05) the water solubility of films within a same polymer concentration. There was a decrease in the films' brightness with the increase of concentration and a decrease of the MW of irradiated chitosan, while the b* values of films increased and there was an increasing tendency of their apparent opacity. - Highlights: • MW reduction by {sup 60}Co irradiation increased the tensil strength of chitosan films. • MW reduction increased the water vapor permeability of chitosan films. • MW did not affect the films' water solubility within a same chitosan concentration. • Films' brightness decreased with the chitosan molecular weight reduction.

  5. Thermoluminescence of Simulated Interstellar Matter after Gamma-ray Irradiation

    CERN Document Server

    Koike, K; Koike, C; Okada, M; Chihara, H

    2002-01-01

    Interstellar matter is known to be strongly irradiated by radiation and several types of cosmic ray particles. Simulated interstellar matter, such as forsterite $\\rm Mg_{2}SiO_{4}$, enstatite $\\rm MgSiO_{3}$ and magnesite $\\rm MgCO_{3}$ has been irradiated with the $\\rm ^{60}Co$ gamma-rays in liquid nitrogen, and also irradiated with fast neutrons at 10 K and 70 K by making use of the low-temperature irradiation facility of Kyoto University Reactor (KUR-LTL. Maximum fast neutron dose is $10^{17}n_f{\\rm /cm^{2}}$). After irradiation, samples are stored in liquid nitrogen for several months to allow the decay of induced radioactivity. We measured the luminescence spectra of the gamma ray irradiated samples during warming to 370K using a spectrophotometer. For the forsterite and magnesite, the spectra exhibit a rather intense peak at about 645 -- 655 nm and 660 nm respectively, whereas luminescence scarcely appeared in olivine sample. The spectra of forsterite is very similar to the ERE of the Red Rectangle.

  6. Study of TL response in heavily irradiated rock salt

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, X.; Dies, X. (Univ. Politecnica de Catalunya, Barcelona (Spain). Inst. de Tecniques Energetiques); Cuevas, C. de las (Barcelona Univ. (Spain))

    1993-01-01

    Within the framework of the CEC R and D Programme ''Management and Storage of Radioactive Waste'', the study of the generation of radiation damage in heavily irradiated rock salt is being carried out. This work describes the experiments carried out for the validation of the TL techniques, in the assessment of the phenomena related to the energy absorbed by the rock salt, due to the high levels of irradiation. The samples analysed are natural rock salt coming from the Sallent mine (Spain). The chemical composition of the rocks is, in all cases, higher than 90% NaCl, having small amounts of SO[sub 4], Mg, K, Br and Sr as major impurities. A first set of irradiations was performed at the laboratory with a source of [sup 137]Cs. The doses reached were lower than 20Gy. A second set of irradiations was performed at an industrial facility with a source of [sup 60]Co, achieving doses up to 2.5 MGy. Afterwards the irradiated samples were analysed with TL and optical absorption techniques. The results have facilitated a study of the glow curves, their evolution in time and the influence of the chemical composition, the absorbed dose, and the absorbed dose rate. These experiments have increased knowledge of the behaviour of heavily irradiated rock salt. (Author).

  7. Comunicación corta. RADIOESTIMULACIÓN DE LA GERMINACIÓN EN Stevia rebaudiana CULTIVAR KH-IAN VC-142 (EIRETÉ, MEDIANTE EL EMPLEO DE RAYOS GAMMA 60CO

    Directory of Open Access Journals (Sweden)

    María C. González

    2015-01-01

    Full Text Available El presente trabajo tuvo como objetivo evaluar el efecto de bajas dosis de rayos gamma 60 Co en la germinación de las semillas de Stevia rebaudiana . Para ello se irradiaron semillas del cultivar KH-IAN VC-142 (Eireté, con dosis de 10 a 90 Gray (Gy. Se determinó que todas las dosis empleadas incrementaron el número de semillas germinadas pero la dosis de 10 Gy fue la que provocó la mayor estimulación en la germinación de las semillas.

  8. A comparison of drought resistance of three zoysiagrasses and their new strains induced by 60Co-γ radiation%3种结缕草及其60Co-γ辐射诱变新品系抗旱性比较

    Institute of Scientific and Technical Information of China (English)

    宋华伟; 刘颖; 曹荣祥; 张巨明

    2015-01-01

    [目的]探究3种结缕草Zoysia japonica及其60Co-γ辐射诱变选育的6种新品系间抗旱性的差异.[方法]以兰引Ⅲ号(LY)、ZS-1 (ZS)和ZS-SJZ (ZSS)3种结缕草及其6种新品系为材料,在盆栽条件下进行干旱胁迫处理,在干旱胁迫处理后第3、9、15天测定叶片相对含水量、相对电导率、脯氨酸含量、可溶性总糖含量,同时观测草坪草盖度和颜色变化;干旱胁迫处理后复水,观测草坪草盖度和颜色变化.[结果和结论]随着干旱胁迫的加剧,结缕草叶片相对含水量不断下降,脯氨酸含量、可溶性总糖含量和相对电导率呈上升趋势,草坪盖度和颜色评分降低.通过隶属函数标准差系数赋予权重法对9份材料的抗旱性进行综合评价,抗旱性从强到弱依次为ZSS-5> ZS-3> LY> LY-2> ZS> ZS-4> LY-1> ZSS-6> ZSS,新品系ZSS-5、ZSS-6、ZS-3抗旱性优于其亲本,说明结缕草可以通过辐射育种选育抗旱品种.

  9. Study on food preservation by irradiation of agricultural and marine products from Cheju island

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.H.; Kim, S.H.; Choung, C.C.; Cho, H.O. (Jeju Univ. (Republic of Korea))

    1984-01-01

    Salted dry yellow sea bream were vaccum packed in a plastic bags and irradiated at differents levels (0,0.5,1.0,1.5, and 2.0 Mrad) using sup(60)Co source. The irradiated samples were stored at room temperature 5degC. Physical and chemical properties were examined during storage. The total bacterial count was depressed according to level of irradiation applied. It was noted that cold storage after irradiation was more effective than room temperature. TMA contents slowly increased with higher dosage rates up to 1.5 Mrad but there was a gradual decrease of TMA at the 2.0 Mrad level. It was observed that there was a rapid decrease of TMAO 20 days after irradiation irrespective of storage temperature. The reduction of total nitrogen content was highest in the control but to a lesser degree when irradiation was applied. VBN content increased in all treatments 30 days after irradiation but it was also noted that there was a tendency toward depression of VBN by irradiation. The shelf life of salted dry sea bream was extended by 20 days with irradiation plus room temperature, and by 40 days with irradiation plus cold storage. To extend shelf life of salted dry sea bream, the most effective dosage rate was 1.0 Mrad based on tenderness, bacterial count and rancidity.

  10. DSC studies of retrogradation and amylose lipid complex transition taking place in gamma irradiated wheat starch

    Science.gov (United States)

    Cieśla, K.; Eliasson, A. C.

    2007-12-01

    The effect of gamma irradiation ( 60Co) with doses of 5-30 kGy on the amylose-lipid complex transition and retrogradation occurring in gels containing ca. 50% and ca. 20% wheat starch was studied by differential scanning calorimetry (DSC) during heating-cooling-heating cycles (up to three cycles). Transition of the amylose-lipid complex occurs in all the irradiated samples at a lower temperature as compared to the non-irradiated starch. That effect was larger when the radiation dose was higher. A further thermal treatment causes a decrease of the transition temperature in the irradiated samples, with no effect or increase of that temperature observed for the non-irradiated ones. Irradiation hinders retrogradation taking place in 50% gels but facilitates the process occurring in 20% gels. The differences between the irradiated and the non-irradiated samples are more evident in the every next heating or cooling cycle as well as after storage and in the case of ca. 50% suspensions as compared to ca. 20% suspensions. The results point out to the deterioration of the structure of the complexes formed in the irradiated starch as compared to the non-irradiated one.

  11. Chemical constituents of Panax ginseng exposed to. gamma. irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Joongho; Belanger, J.M.R.; Sigouin, M.; Lanthier, J.; Willemot, C.; Pare, J.R.J. (Agriculture Canada, Saint-Hyacinthe, Quebec (Canada))

    1990-03-01

    Chemical constituents were monitored to assess the biochemical and nutritional safety of Panax ginseng powders that were irradiated at doses of 1-10 kGy. Quantitative analysis has shown that the main effective components - saponins - are not altered by {sup 60}Co {gamma} irradiation. Ginsenoside-Rg{sub 1} was not affected by the treatment. Negligible changes were observed in the free carbohydrate contents. Doses of more than 5 kGy caused significant decreases in sulfur-containing amino acids and in tyrosine. At doses of 10 kGy, free amino acids, such as proline and lysine, showed an appreciable increase. The composition in minerals was not altered irrespective of the applied doses.

  12. Effects of gamma irradiation on electric characteristics of power diodes

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Renata F.; Santos, Thais C. dos; Pascoalino, Kelly C.; Goncalves, Josemary A.C.; Tobias, Carmen C.B., E-mail: ccbueno@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    In this work we presented the preliminary results of a systematic study of direct voltage and cut-off frequency variations of power diodes under different gamma irradiation doses. The samples were irradiated at a gamma facility, {sup 60}Co-Gammacell 220 (dose rate of 2.31 kGy/h), in the Radiation Technology Center (CTR) at IPEN/CNEN-SP. The temperature during exposure was typically 25 deg C. The values of direct voltage and the temporal response of the devices were studied for an accumulated dose of 1350 kGy. The results have shown an improvement of the reverse recovery behavior of this type of diode, as well as a 10% decrease in its direct voltage. (author)

  13. Different gamma radiation doses effects of {sup 60} Co on buds of banana plant (Nanicao-AAA) breeded in vitro; Efeito de diferentes doses de radiacao gama do {sup 60} Co em gemas de bananeira (Nanicao-AAA) desenvolvidas in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Gilberto Dias [Pernambuco Univ., Recife, PE (Brazil). Dept. de Botanica; Andrade, Arnobio Goncalves de [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Lab. de Quimica Vegetal; Kido, Laureen Michelle Houllou; Franca, Jose Geraldo Eugenio de [Empresa Pernambucasna de Pesquisa Agropecuaria (IPA), Recife, (Brazil); Colaco, Waldeciro [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear

    1999-11-01

    Buds from banana cv. Nanicao-AAA (3 mm x 3 mm) were aseptically cultured in a modified Murashige and Skoog (MS) basal medium supplement with bezylaminepurine and sucrose, and solidified with agar. Buds placed on sterile Petri dishes were irradiated with increasing gamma rays doses (10, 20, 30, and 40 Gy). The statistical design was completely randomized with 5 doses and 30 replications. After irradiation, buds were transferred to 10 ml of the same medium into test tubes, and allowed to grow in a controlled environment (25 deg C, 16 h illumination ) for 4 weeks. There were no significant differences (Tukey, 0,05) between doses in terms of oxidation: in around 20% for all treatments. On the other hand, a statistically significant decrease in the germination of new buds with increased doses of irradiation was observed. The treatment with 40 Gy reduced in 80% the germination of new buds by the end of the evaluated period (4 weeks), resulting in a mean production of 1,5 buds. Mean production in the control was 7,6 buds. no statistically significant differences were detected between treatments with 10, 20, and 30 Gy, with a mean production of 3 buds, less than half obtained in the control. (author) 9 refs., 2 figs.

  14. Effect of gamma irradiation on nutrient digestibility in SPF mini-pig

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jun-Yeob [College of Animal Life Sciences , Kangwon National University, 192-1 Kangwon Avenue 1, Chuncheon, Gangwon-do 200-701 (Korea, Republic of); Cho, Sung-Back [Swine Science Division, National Institute of Animal Science, Cheonan, Chungcheongnam-do 330-801 (Korea, Republic of); Kim, Yoo-Yong [College of Agriculture and Life Science, Seoul National University, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Ohh, Sang-Jip, E-mail: sjohh@kangwon.ac.k [College of Animal Life Sciences , Kangwon National University, 192-1 Kangwon Avenue 1, Chuncheon, Gangwon-do 200-701 (Korea, Republic of)

    2011-01-15

    This study was carried out to evaluate the effect of gamma irradiation on nutrient digestibility of either soy-based or milk-based diet for specific pathogen-free (SPF) mini-pigs. Gamma irradiation of the diets was done at dosage of 10 kGy with {sup 60}Co whereas autoclaving was executed at 121 {sup o}C for 20 min. Apparent crude protein digestibilities of gamma irradiated diets were higher (p<0.05) than those of autoclaved diets regardless of diet type. Digestibilities of dry matter, gross energy and total carbohydrate in the irradiated diet were higher than those of the autoclaved diet. From the results of nutrient digestibility of mini-pig diets in this study, 10 kGy gamma radiation was suggested as a convenient diet radicidation method that can minimize the decrease in nutrient digestibility on feeding to SPF mini-pigs.

  15. γ-Ray irradiation stability and damage mechanism of glycidyl amine epoxy resin

    Science.gov (United States)

    Diao, Feiyu; Zhang, Yan; Liu, Yujian; Fang, Jun; Luan, Weilin

    2016-09-01

    Irradiation stability of triglycidyl-p-aminophenol (TGPAP) epoxy resins was evaluated according to the changes of physico-chemical and mechanical properties under 60Co γ-ray irradiation with a dose rate of 10 kGy/h. The result shows that with the increase of radiation dose, bending strength, thermal stability, free radical concentration and storage modulus of epoxy resin decrease first, then increase slightly, and decline sharply at the end with a dose of 960 kGy, due to competition effects between radiation-induced degradation and cross-linking reaction. The damage mechanism was derived by analyzing structure and composition change of AFG-90 resins after irradiation via IR and XPS. Irradiation will result in weak bond breaking such as Csbnd C and Csbnd N bond, and new bond forming like Cdbnd C and Cdbnd O.

  16. Experience in Cuba in the licensing during import, commissioning and operation of an Irradiator LLCo ISOGAMMA; Experiencia en Cuba en el licenciamiento durante la importacion, puesta en servicio y operacion de un irradiador ISOGAMMA LLCo

    Energy Technology Data Exchange (ETDEWEB)

    Forteza, Yamil Lopez; Reyes, Yolanda Perez; Garcia, Jose R. Quevedo; Molina, Igor I. Sarabia; Gonzalez, Leonel Omarovich; Zubiaur, Omar Cruz, E-mail: yamil@orasen.co.cu, E-mail: yolanda@orasen.co.cu, E-mail: quevedo@orasen.co.cu [Ministerio de Ciencia, Tecnologia y Medio Ambiente (CNSN/CITMA), La Habana (Cuba). Centro Nacional de Seguridad Nuclear

    2013-07-01

    This work presented the experiences during the process of licensing an irradiator ISOGAMMA LLCo model according to the recommendations of the International Atomic Energy (IAEA). Aspects of the safety assessment are detailed, as well as control and verification requirements for radiation safety and security at different stages of the process (import, transportation, installation irradiator loading 60Co sources, commissioning and operation) of irradiator recently installed in Cuba. The results of the evaluation carried a source of reference and consultation necessary for the work of the regulator to consider for similar processes that lie ahead in other facilities irradiation.

  17. Development of detection methods for irradiated foods - Detection method for radiolytic products of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Su; Kim, Sun Min; Park, Eun Ryong; Lee, Hae Jung; Kim, Eun Ah; Jo, Jung Ok [Chosun University, Kwangju (Korea)

    1999-04-01

    Meat (beef, pork, chicken) and nut (sesame, perilla, black sesame, peanut) were irradiated with /sup 60/Co gamma-ray. A process to detect radiation-induced hydrocarbons and 2-alkylcyclobutanones includes the extraction of fat from meat and nut, separation of hydrocarbons and 2-alkylcyclobutanones with a florisil column and identification of GC/MS methods. Concentrations of the produced hydrocarbons and 2-alkylcyclobutanones tended to increase linearly with the dose levels of irradiation in beef, pork and chicken, while concentrations of radiation-induced hydrocarbons were different individually at the same dose level. In meat, hydrocarbons and 2-alkylcyclobutanones originated from oleic acid were found in a large amount. The concentrations of radiation-induced hydrocarbons were relatively constant during 16 weeks. In nut, hydrocarbons originated from oleic acid and linoleic acid were the major compounds whereas results of perilla was similar to meat. Radiation-induced hydrocarbons were increased linearly with the irradiation dose and remarkably detected at 0.5 kGy and over. 44 refs., 30 figs., 14 tabs. (Author)

  18. Teratogenic effect of Californium-252 irradiation in rats

    Energy Technology Data Exchange (ETDEWEB)

    Satow, Yukio; Lee, Juing-Yi; Hori, Hiroshi; Okuda, Hiroe; Tsuchimoto, Shigeo; Sawada, Shozo; Yokoro, Kenjiro (Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology)

    1989-06-01

    The teratogenicity of Californium-252 (Cf-252) irradiation which generates approximately 70% 2.3 MeV fast neutron and 30% gamma rays was evaluated. A single whole body exposure of Cf-252 at various doses was given to pregnant rats on day 8 or 9 of pregnancy, followed by microscopic autopsy of the fetuses at the terminal stage of pregnancy to search for external and internal malformations. For comparison, pregnant rats were irradiated with various doses of Cobalt-60 (Co-60) standard gamma rays at the same dose rate (1 rad/min.). The doses were 20-120 rad of Cf-252 and 80-220 rad of Co-60. Using frequency of radiation induced malformations observed on day 8 of pregnancy as an index, relative biological effectiveness (RBE) of 2.3-2.7 was obtained from the straight line obtained by modifying by the least squares method the frequency curves of malformed fetuses in total implants and in surviving fetuses. The types of malformations induced by Cf-252 and Co-60 irradiation were alike. Using fetal LD/sub 50/ as an index, 2.4 was obtained as RBE when irradiated on day 8 of pregnancy and 3.1 as that when irradiated on day 9. The results showed that Cf-252 had stronger a teratogenic effect than Co-60 gamma rays. (author).

  19. EPR investigation of some traditional oriental irradiated spices

    Science.gov (United States)

    Duliu, Octavian G.; Georgescu, Rodica; Ali, Shaban Ibrahim

    2007-06-01

    The 9.50 GHz electron paramagnetic resonance (EPR) spectra of unirradiated and 60Co γ-ray irradiated cardamom ( Elettaria cardamomum L. Maton, Zingiberaceae), ginger (( Zingiber officinale Rosc., Zingiberaceae), and saffron ( Crocus sativus L., Iridaceae) have been investigated at room temperature. All unirradiated spices presented a weak resonance line with g-factors around free-electron ones. After γ-ray irradiation at an absorbed dose of up to 11.3 kGy, the presence of EPR spectra whose amplitude increase monotonously with the absorbed dose has been noticed with all spices. A 100 °C isothermal annealing of 11.3 kGy irradiated samples has shown a differential reduction of amplitude of various components that compose initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after 83 days storage at room temperature but after 340 days storage at ambient conditions only irradiated ginger displays a weak signal that differs from those of unirradiated sample. All these factors could be taken into account in establishing at which extent the EPR is suitable to evidence any irradiation treatment applied to these spices.

  20. Gamma-ray Irradiation Induces Useful Morphological Variation in Bermudagrass

    Directory of Open Access Journals (Sweden)

    Songul SEVER MUTLU

    2015-12-01

    Full Text Available Bermudagrass, Cynodon dactylon (L. Pers. is a widely used warm-season turfgrass species in warmer regions of the world. Gamma (ɣ irradiation has been used to generate useful variations in turfgrass breeding for various morphological traits. The objective of the present study was to measure and determine variations in morphology and turfgrass characteristics of a native drought resistant bermudagrass germplasm irradiated with 70, 90 or 110 Gy using a 60Co source. The stolons containing a single node were irradiated and immediately planted for regeneration in a greenhouse at the Akdeniz University, Antalya, Turkey. Selected mutants regenerated from the irradiated stolons were clonally propagated and transplanted into plastic pots for further observations of turfgrass characteristics.  Survival rates of stolons exposed to 70, 90 and 110 Gy were 76%, 43% and 17% respectively, 6 weeks after treatment. Dosages of 85 and 57 Gy were determined as LD50 and LD20 for the cuttings, respectively. The linear reduction of survival rate with increasing gamma-rays was highly correlated (r2=0.99. A total of four mutant lines (0.3 % of the irradiated plants showed a distinct dwarfed growth habit. Three of these lines were originated from 70 Gy and one from 110 Gy. These mutant lines exhibited more dwarf growth habit, higher shoot density, finer leaf texture than parental genotype. Mutant lines developed in this study can be used for the development of improved bermudagrass cultivars for landscaping and sports turf.

  1. EPR investigation of some traditional oriental irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Duliu, Octavian G. [University of Bucharest, Department of Atomic and Nuclear Physics, Magurele, C.P. MG-11, RO-077125 Bucharest (Romania)]. E-mail: duliu@pcnet.ro; Georgescu, Rodica [National Institute for Physics and Nuclear Engineering -Horia Hulubei, C.P. MG-6, RO-077125 Bucharest (Romania); Ali, Shaban Ibrahim [University of Bucharest, Department of Atomic and Nuclear Physics, Magurele, C.P. MG-11, RO-077125 Bucharest (Romania)

    2007-06-15

    The 9.50 GHz electron paramagnetic resonance (EPR) spectra of unirradiated and {sup 60}Co {gamma}-ray irradiated cardamom (Elettaria cardamomum L. Maton, Zingiberaceae), ginger ((Zingiber officinale Rosc., Zingiberaceae), and saffron (Crocus sativus L., Iridaceae) have been investigated at room temperature. All unirradiated spices presented a weak resonance line with g-factors around free-electron ones. After {gamma}-ray irradiation at an absorbed dose of up to 11.3 kGy, the presence of EPR spectra whose amplitude increase monotonously with the absorbed dose has been noticed with all spices. A 100 {sup o}C isothermal annealing of 11.3 kGy irradiated samples has shown a differential reduction of amplitude of various components that compose initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after 83 days storage at room temperature but after 340 days storage at ambient conditions only irradiated ginger displays a weak signal that differs from those of unirradiated sample. All these factors could be taken into account in establishing at which extent the EPR is suitable to evidence any irradiation treatment applied to these spices.

  2. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Angelo, E-mail: aalberti@isof.cnr.it [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Chiaravalle, Eugenio [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Fuochi, Piergiorgio; Macciantelli, Dante [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Mangiacotti, Michele, E-mail: michelemangiacotti@libero.it [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Marchesani, Giuliana [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Plescia, Elena [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy)

    2011-12-15

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with {sup 60}Co {gamma}-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, SO{sub 2}{sup -} and SO{sub 3}{sup -} radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: > EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. > A conchiolin-derived radical can be used as irradiation marker for some mollusks. > A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  3. Production and characterization of antibodies against irradiated human erythrocytes membrane proteins

    Energy Technology Data Exchange (ETDEWEB)

    Amancio, Francisco F. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]|[Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia; Andrade Junior, Heitor F. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Inst. de Medicina Tropical

    1997-12-01

    Gamma irradiation affects people in several situations, with few if any sensitive biological assay of its action. Nucleic acids and proteins are affected by radiation, but only the former was used in most dosimetric techniques. The irradiation of proteins promotes structural modifications attributed to free radicals from water radiolysis. Theoretically, antibodies induced by irradiated proteins could recognize these radical-related new epitopes, allowing their use as a probe. Human erythrocyte membrane proteins (HEMP), few and well defined molecules, are certainly exposed to radiation, being the ideal target. With this rationale, we study the production of antibodies in mice immunized with {sup 60} Co irradiated HEMPs. Menbranes from hypotonic lysis with differential centrifugation of A+ erythrocytes, were irradiated in a Gammacell 220 with 400, 800 and 1600 Gy, and used as immunogen for Balb/c mice, after SDS-PAGE. Irradiated HEMP induced antibodies recognize only irradiated human erthrocytes in an intact cell indirect immunofluorescence assay (ICIIFA). When used in Wester-blot against non-irradiated HEMPs, those sera recognize most proteins, suggesting a pool of abs directed both to native, as detected by Western Blot, or irradiated, as detected by ICIFA, HEMPs. Those data confirmed our assumptions, allowing the use of those abs in the search for a method of biological dosimetry. (author). 18 refs., 3 figs.

  4. Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Jose R., E-mail: joseroberto.soares@mackenzie.br [Universidade Presbiteriana Mackenzie. Escola de Engenharia. Sao Paulo, SP (Brazil); Rela, Paulo R.; Costa, Fabio E., E-mail: prela@ipen.br, E-mail: fecosta@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes {sup 60}Co as radiation source. The developed work provides an accurate control and data acquisition for the application of good manufacturing practices during all phases of an irradiation process, required by the standards of ANVISA, technical ISO and IAEA recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The automatic data process acquisition using wireless ZigBee technology, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN-SP all the development was performed to be applied in irradiators' facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

  5. Comparison between different types of glass and aluminum as containers for irradiation samples by neutron activation analysis.

    Science.gov (United States)

    Sroor, A; El-Dine, N W; El-Shershaby, A; Abdel-Haleem, A S

    2000-01-01

    Three different types of glass and four different kinds of aluminum sheet have been analyzed using neutron activation analysis. The irradiation facilities of the first Egyptian research reactor (ET-RR-1) and a hyper-pure germanium (HPGe) detection system were used for the analysis. Among the 34 identified elements, the isotopes 60Co, 65Zn, 110mAg, 123mTe, 134Cs, 152Eu and 182Ta are of special significance because of their long half-lives, providing a background interference for analyzed samples. A comparison between the different types of containers was made to select the preferred one for sample irradiation.

  6. Evaluation of the ionizing radiation {sup 60}Co effect on the physical, chemical and nutritional properties of different cultivars of soybean grains (Glycine max (L.));Avaliacao dos efeitos da radiacao ionizante de {sup 60}Co em propriedades fisicas, quimicas e nutricionais de diferentes cultivares de graos de soja Glycine max (L.)

    Energy Technology Data Exchange (ETDEWEB)

    Toledo, Tais Carolina Franqueira de

    2006-07-01

    With the increase of the world population, creative strategies will be necessary to control food production. To achieve this challenge, new cultivars have been development, though different techniques and characteristics. To improve food conservation, a plant of methods can be used. The use of Cobalto-60 radiation is a secure and useful method to increase the life time of foods. Due to the commercial and nutritional importance of soybean, some alterations must be studied. This study has the objective to determinate this alterations caused by irradiation (with doses of 2, 4 and 8 kGy) in raw and cooked grain of five different cultivars of soybean (BRS 212, BRS 213, BRS 214, 231 BRS and E48), this study includes analysis of time cooking and hydratation, and chemical analysis of proximate composition, in vitro digestibility of proteins, percentage of deamidation , phenolics compounds, trypsin inhibitors and tannins. The amount of water absorbed by each grain varied from 14.00 to 16.66mL, and the time cooking varied from 119.67 to 291.33 minutes. The values found for ash were 4.90 to 6.08%, for protein from 21.23 to 36.99%, for fat from 19.22 to 24.84%, soluble staple fibres from 1.37 to 4.03% and insoluble staple fibres from 15.97 to 18.87%. The deamidation percentage in the different samples varied of 17,34 to 57.79% and the digestibility in vitro from 84.45 to 89.11%. Inside of the anti nutritional factors, the total compounds phenolics varied from 3.9 to 9.7 mg/g, the units of trypsin inhibited from 24.75 to 57.53 UTI/g and the tannins from 0.02 to 0.32 mg/g. For the physical analyses it showed differences in the time of hydratation among them and the irradiation promoted reduction in the time, but not in the amount of absorbed water; in the cooking time it had reduction with the increase of the doses of radiation; the differences found in the proximate composition did not have influence with the irradiation, but with the different cultivars; for the digestibility

  7. 抗弓形虫速殖子单克隆抗体的制备与特性研究%STUDY ON THE PREPARATION AND CHARATERIZATION OFA MONOCLONAL ANTIBODY TO TOXOPLASMA GONDH TACHYZOITES

    Institute of Scientific and Technical Information of China (English)

    朱云娟; 杨秀珍; 杨树森

    2000-01-01

    Aim To prepare and identify monodonal sntibody (Mab) specific for Toaoplasma gondii tachyzoites. Method The Mab specific for Taxoplasma gondii tachyrzoite were prepared via bybridoma technique. Indirect ELISA was used to determine the activity of the Mab. Agarose double immuodiffusion test was performed to confirm subclass and SDS-PAGE & western blot were used to analysis rolecular weight of the antigen (s) recognized by the Mab. IFA was used to identify the epitope of Taxoplasma gondii tachyzoites. The protection and specificity of the Mab were snalysed at same time. The Mab was tesed in Mab-ELISA method to detect Taxoplasma gondii antigen. Results A Msb F7C8H12 specific for T. gondii was produced. It belongs to IgG1 subclass. Moleculsr weight of the sntigens recognized by the Mab was 16.5 and 24 kDa. IFA did not show fiuorescence in intact tachyzoite.Inhibition test showed that the inhibition rate was 50% when the concetration of the antigen was 40μg/ml.Afterthe RH strain tachyzoites were incubated with Mab ascites, mice were inected with the tachyzoites through peritoneum. The results showed that the mean dead time of mice were not delayed. T. gondii antigen mixed with PBS snd normal human serum was detected by Mab-ELISA, the sensitvity was 0.78 yg/ml and 1.5μg/ml respectively. When mice were infected with T. gondiiRH strain tachyzoites, 103/mouse p.i., circulating antigen could be detectedin 6 day and 8 day. Conchusion The Mab (F7C8H12) to T. gomdii tachyzoites is an excellent probe for studying T. gondii snd toxoplasmosis.%目的 制备抗弓形虫速殖子单克隆抗体(Mab),并对其特性进行分析,探讨其在弓形虫病诊断中的作用。方法 利用杂交瘤技术制备抗弓形虫速殖子Mab。用间接ELISA法测定活性,以琼脂糖免疫双扩散鉴定亚类,通过SDS-PAGE和Westernblot分析该Mab所识别的抗原分子量,以IFA确定抗原位点在虫体的定位,并对其保护性及特异性进行分析。通过Mab

  8. Thalidomide combined with irradiation alters the activity of two proteases.

    Science.gov (United States)

    Şimşek, Ece; Aydemir, Esra; Korcum, Aylin Fidan; Fişkın, Kayahan

    2015-02-01

    The aim of the present study was to investigate the effects of thalidomide, a drug known for its anti‑angiogenic and antitumor properties, at its cytotoxic dose previously determined as 40 µg/ml (according to four cytotoxic test results). The effect of the drug alone and in combination with radiotherapy using Cobalt 60 (60Co) at 45 Gy on the enzymatic activity of substance‑P degrading A disintegrin and metalloproteinase (ADAM)10 and neprilysin (NEP) was investigated in the mouse breast cancer cell lines 4T1 and 4T1 heart metastases post‑capsaicin (4THMpc). Thalidomide (40 µg/ml) exerted differing effects on the activities of ADAM10 and NEP enzymes. In 4T1 cells, 40 µg/ml thalidomide alone did not alter ADAM10 enzyme activity. 60Co irradiation at 45 Gy alone caused a 42% inhibition in ADAM10 activity, however, the inhibition increased to 89% when combined therapy was used. By contrast, in the 4THMpc cell line, 40 µg/ml thalidomide alone induced a 66.6% increase in ADAM10 enzyme activity. Radiotherapy alone and thalidomide with 60Co combined therapy caused a 33.3 and 40% inhibition of ADAM10 activity, respectively. In 4T1 cells, thalidomide alone caused a 40.9% increase in NEP activity. Radiation therapy alone or in combination with the drug caused a 40.7% increase in NEP activity. In more aggressive 4THMpc cells, thalidomide alone caused a 26.6% increase in NEP activity. Radiotherapy alone and combined therapy caused a 33.3 and 37% increase in enzyme activity, respectively. To the best of our knowledge, the present study is the first to demonstrate that thalidomide alone or in combination with radiotherapy exhibits significant cytotoxic effects on 4T1 and 4THMpc mouse breast cancer cell lines indicating that this drug affects the enzymatic activity of ADAM10 and NEP in vitro.

  9. Report on EUROMET.RI(I)-K1 and EUROMET.RI(I)-K4 (EUROMET project no. 813): Comparison of air kerma and absorbed dose to water measurements of {sup 60}Co radiation beams for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Csete, I. [National Office of Measures (OMH) - pilot laboratory and corresponding author (Hungary); Leiton, A.G. [Research Centre for Energy, Environment and Technology (CMRI-CIEMAT) (Spain); Sochor, V. [Czech Metrology Institute (CMI) (Czech Republic); Lapenas, A. [Latvian National Metrology Center (LNMC-RMTC) (Latvia); Grindborg, J.E. [Swedish Radiation Protection Authority (SSI) (Sweden); Jokelainen, I. [Radiation and Nuclear Safety Authority (STUK) (Finland); Bjerke, H. [Norwegian Radiation Protection Authority (NRPA) (Norway); Dobrovodsky, J. [Slovak Institute of Metrology (SMU) (Slovakia); Megzifene, A. [International Atomic Energy Agency, IAEA, Vienna (Austria); Hourdakis, C.J. [Hellenic Atomic Energy Committee (HAEC-HIRCL) (Greece); Ivanov, R. [National Centre of Metrology (NCM) (Bulgaria); Vekic, B. [Rudjer Boskovic Institute (IRB) (Croatia); Kokocinski, J. [Central Office of Measures (GUM) (Poland); Cardoso, J. [Institute for Nuclear Technology (ITN-LMRIR) (Portugal); Buermann, L. [Physikalisch Technische Bundesanstalt (PTB) (Germany); Tiefenboeck, W. [Bundesamt fur Eich und Vermesungswesen (BEV) (Austria); Stucki, G. [17 Bundesamt fur Metrologie (METAS) (Switzerland); Van Dijk, E. [NMi Van Swinden Laboratorium (NMi) (Netherlands); Toni, M.P. [ENEA-CR Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti (ENEA) (Italy); Minniti, R. [20 National Institute of Standards and Technology (NIST) (United States); McCaffrey, J.P. [National Research Council Canada (NRC) (Canada); Silva, C.N.M. [National Metrology Laboratory of Ionizing Radiation (LNMRI-IRD) (Brazil); Kharitonov, I. [D I Mendeleyev Institute for Metrology (VNIIM) (RU); Webb, D. [Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) (Australia); Saravi, M. [National Atomic Energy Commission (CNEA-CAE) (Argentina); Delaunay, F. [Laboratoire National Henri Becquerel (LNE-LNHB) (France)

    2010-06-15

    The results of an unprecedented international effort involving 26 countries are reported. The EUROMET.RI(I)-K1 and EUROMET.RI(I)-K4 key comparisons were conducted with the goal of supporting the relevant calibration and measurement capabilities (CMC) planned for publication by the participant laboratories. The measured quantities were the air kerma (K{sub air}) and the absorbed dose to water (Dw) in {sup 60}Co radiotherapy beams. The comparison was conducted by the pilot laboratory MKEH (Hungary), in a star-shaped arrangement from January 2005 to December 2008. The calibration coefficients of four transfer ionization chambers were measured using two electrometers. The largest deviation between any two calibration coefficients for the four chambers in terms of air kerma and absorbed dose to water was 2.7% and 3.3% respectively. An analysis of the participant uncertainty budgets enabled the calculation of degrees of equivalence (DoE), in terms of the deviations of the results and their associated uncertainties. As a result of this EUROMET project 813 comparison, the BIPM key comparison database (KCDB) will include eleven new Kair and fourteen new D{sub w} DoE values of European secondary standard dosimetry laboratories (SSDLs), and the KCDB will be updated with the new DoE values of the other participant laboratories. The pair-wise degrees of equivalence of participants were also calculated. In addition to assessing calibration techniques and uncertainty calculations of the participants, these comparisons enabled the experimental determinations of N{sub Dw}/N{sub Kair} ratios in the {sup 60}Co gamma radiation beam for the four radiotherapy transfer chambers. (authors)

  10. Tenth value layers for 60Co gamma rays and for 4, 6, 10, 15, and 18 MV x rays in concrete for beams of cone angles between 0 degrees and 14 degrees calculated by Monte Carlo simulation.

    Science.gov (United States)

    Jaradat, Adnan K; Biggs, Peter J

    2007-05-01

    The calculation of shielding barrier thicknesses for radiation therapy facilities according to the NCRP formalism is based on the use of broad beams (that is, the maximum possible field sizes). However, in practice, treatment fields used in radiation therapy are, on average, less than half the maximum size. Indeed, many contemporary treatment techniques call for reduced field sizes to reduce co-morbidity and the risk of second cancers. Therefore, published tenth value layers (TVLs) for shielding materials do not apply to these very small fields. There is, hence, a need to determine the TVLs for various beam modalities as a function of field size. The attenuation of (60)Co gamma rays and photons of 4, 6, 10, 15, and 18 MV bremsstrahlung x ray beams by concrete has been studied using the Monte Carlo technique (MCNP version 4C2) for beams of half-opening angles of 0 degrees , 3 degrees , 6 degrees , 9 degrees , 12 degrees , and 14 degrees . The distance between the x-ray source and the distal surface of the shielding wall was fixed at 600 cm, a distance that is typical for modern radiation therapy rooms. The maximum concrete thickness varied between 76.5 cm and 151.5 cm for (60)Co and 18 MV x rays, respectively. Detectors were placed at 630 cm, 700 cm, and 800 cm from the source. TVLs have been determined down to the third TVL. Energy spectra for 4, 6, 10, 15, and 18 MV x rays for 10 x 10 cm(2) and 40 x 40 cm(2) field sizes were used to generate depth dose curves in water that were compared with experimentally measured values.

  11. Current situation of food irradiation practice in U.S.A

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu [Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology

    1996-12-31

    It is essential that private food companies adopt the process and retail stores sell irradiated food products in order to popularize food irradiation among consumers. FOOD TECHnology Inc. (former Vindicator Inc.), which is founded in Florida 1992 for the purpose of decontamination of fruit flies infected in Oranges using {sup 60}Co gamma-irradiation, and Carrot Top, which has been selling irradiated foods since 1992, are well known to be actively involved in PA activity of irradiated foods. Carrot Top is now strongly interested in selling tropical fruits from Hawaii, which has been prohibited to ship from Hawaii to the mainland without decontamination treatment by US government because of fruit fly infestation. They got a temporal permit for the shipment of those fruits with irradiation at Chicago. FOOD TECHnology Inc. irradiates chicken, tomatoes, strawberries and mushrooms. Foods for hospitalized patients and astronauts are also irradiated at FOOD TECHnology Inc.. All food supply for the `Space Shuttle` program has been provided. Recently they began to irradiate frozen shrimps and salmons. Carrot Top says that irradiated food items gain popularity among their customers although they changed the information transfer method from news letter to news paper advertisement as well as minimizing the description in the store. They noted that the goods sold well whether or not they are irradiated if they are fresh, good-looking and reasonable in price. FOOD TECHnology also commented that food industries has become more friendly towards food irradiation and they petitioned FDA for clearance of beef irradiation to decontaminate E. coli 0157:H7, but the private companies still hesitated to pick up this process therefore we need more efforts of PR. (J.P.N.)

  12. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    Energy Technology Data Exchange (ETDEWEB)

    Todoriki, Setsuko [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan)], E-mail: setsuko@affrc.go.jp; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan); Kanamori, Norihito [Japan International Research Center for Agricultural Science, Tsukuba, Ibaraki 305-8686 (Japan); Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio [School of Agriculture, Kinki University, Nara-city, Nara 631-8505 (Japan); Kawamoto, Shinichi [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan)

    2009-07-15

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a {sup 60}Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 deg. C. Additionally, the m-RNA levels of {beta}-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  13. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    Science.gov (United States)

    Todoriki, Setsuko; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka; Kanamori, Norihito; Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio; Kawamoto, Shinichi

    2009-07-01

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a 60Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 °C. Additionally, the m-RNA levels of β-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  14. Study and application of surface antigen in tachyzoites of Toxoplasma gondii%刚地弓形虫速殖子表面抗原的研究及应用

    Institute of Scientific and Technical Information of China (English)

    冷丽; 罗米; 高菊; 申丽洁

    2014-01-01

    弓形虫是一种专性细胞内寄生原虫,能感染包括人在内的所有温血动物。近年来弓形虫速殖子表面抗原已成为候选的诊断和疫苗抗原,主要包括P30、P22、P43、P35和P23等,本文就此做一综述。%Toxoplasma gondii is an intracellular protozoan parasite that infects all warm⁃blooded animals. The surface anti⁃gens of T. gondii with the potential for application as antigens of diagnosis and vaccines have been studied extensively in recent years especially for P43 P35 P30 P23 and P22. The studies on the surface antigen in tachyzoites of T. gondii are reviewed in this paper.

  15. Description of morphologic characters in avocado trees (Persea americana. Mill) var. Hass, submitted to gamma radiation of {sup 60} Co; Descripcion de caracteres morfologicos en arboles de aguacate (Persea americana. Mill) var. Hass, sometidos a radiacion gama de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval R, L

    2004-07-01

    It was carried out the characterization of 77 trees of avocado ''Hass'' subjected to gamma radiation of Co{sup 60}, in doses of 0, 5, 10,15, 20 and 25 Gy based on previous studies of radiosensitivity with ends of improvement located in the experimental center ''La Labor'' belonging to the foundation Salvador Sanchez Colin. CICTAMEX. S C. in Temascaltepec, Mexico. It was carried out the morphological characterization of this variety according to the nomenclature settled down by the International Office of Genetic Resources (IBPGRI), registering 27 variables for the description of the tree, 33 for description of the fruit and 14 for the characterization of the seed. Regarding the architectural characterization 10 variables were evaluated. Using gamma radiation of Co{sup 60} in the doses of 15 and 20 Gy it was detected a reduction of 22% in the portage of the tree, likewise had reduction the diameter of the trunk and of the foliage. It was found that the reduction in the behavior of the tree induces to a bigger variation of the form of the same one, in the distribution of the branches in the form of the fruit and in the form of the seed you Also detects a remarkable increment in the productivity of some hoist irradiated regarding the architecture of the tree one observes that the angle of inclination of the branches increase when being increased the radiation dose and that the longitude of the annual section of growth decreased significantly in the doses of 20 and 25 Gy. One observes a significant Increment in the I number of buds prolepticos in those hoist irradiated in the I finish mbdulo of rhythmic growth. Io that indicates a change substantial in the I inhabit of growth With the purpose of determining if the changes in morphology and architecture of the tree corresponded with the modification at level meristematico, they were carried out observations to the court microscope of having knitted apical vegetative meristematico

  16. Sensitivity of P-Channel MOSFET to X- and Gamma-Ray Irradiation

    Directory of Open Access Journals (Sweden)

    Milić Pejović

    2013-01-01

    Full Text Available Investigation of Al-gate p-channel MOSFETs sensitivity following irradiation using 200 and 280 kV X-ray beams as well as gamma-ray irradiation of 60Co in the dose range from 1 to 5 Gy was performed in this paper. The response followed on the basis of threshold voltage shift and was studied as a function of absorbed dose. It was shown that the most significant change in threshold voltage was in the case of MOSFET irradiation in X-ray fields of 200 kV and when the gate voltage was +5 V. For practical applications in dosimetry, the sensitivity of the investigated MOSFETs was also satisfactory for X-ray tube voltage of 280 kV and for gamma rays. Possible processes in gate oxide caused by radiation and its impact on the response of MOSFETs were also analyzed in this paper.

  17. Monte Carlo simulation of indirect damage to biomolecules irradiated in aqueous solution: The radiolysis of glycylglycine

    Energy Technology Data Exchange (ETDEWEB)

    Bolch, W.E.; Turner, J.E.; Yoshida, H.; Jacobson, K.B.; Hamm, R.N.; Wright, H.A.; Ritchie, R.H.; Klots, C.E.

    1988-07-01

    A Monte Carlo computer code is developed for simulating the radiolysis of glycylglycine in both oxygenated and deoxygenated aqueous solution. Second, this model is used to calculate the yields of various products in solutions irradiated either by 250-kVp X-rays or by /sup 60/Co gamma rays. Third, calculated product yields are compared to measured yields where available. The Monte Carlo computer codes used in this study are modified and extended versions of three existing simulation codes, written at the Oak Ridge National Laboratory (ORNL), which simulate irradiations of pure liquid water. The ORNL codes calculate the formation, diffusion, and reaction of free radicals and other species along charged-particle tracks in liquid water. As part of this research, these codes are extended to simulate irradiation of pure oxygenated water, oxygenated glycylglycine solutions, and deoxygenated glycylglycine solutions. 80 refs., 38 figs., 8 tabs.

  18. Electron spin resonance studies on PS, PP and PS/PP blends under gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, Jacobo E-mail: reyesj@camelot.rect.ucv.ve; Albano, Carmen E-mail: calbano@ivic.vealbanoc@camelot.rect.ucv.ve; Claro, Marjorie; Moronta, Delfin

    2003-06-01

    Electron spin resonance studies on polystyrene (PS), polypropylene (PP) and on 80/20 PS/PP blends with and without compatibilizer (block SBS), at 7.5 wt%, irradiated with gamma rays from a {sup 60}Co source at a dose rate of 4.8 kGy/h and at integral irradiation doses of 10, 25, 50, 60, 70, 400, 800 and 1300 kGy in the presence of air and at room temperature are reported. Dependence of resonance line width, Hpp, resonance line shapes, K, and resonance line intensity, Ipp, on the integral dose of irradiation is investigated. Nature of free radicals after 10 days of air storage is discussed.

  19. Microscopic investigations on various silicon materials irradiated with different particles with the DLTS method

    Energy Technology Data Exchange (ETDEWEB)

    Kuhnke, M.

    2001-02-01

    During irradiation of crystalline silicon with high energy particles silicon atoms are displaced out of their lattice sites and the primary defects silicon interstitials and vacancies from defects with the impurities oxygen and carbon. The radiation induced defects change the macroscopic parameters of silicon detectors, the leakage current and the full depletion voltage. The item of this thesis is to study the microscopic properties of radiation induced defects with the DLTS method and to understand the change of the macroscopic parameters of silicon detectors after particle irradiation. Various silicon materials were irradiated with low and high energy protons, high energy pions, neutrons and {sup 60}Co {gamma}-photons to investigate the dependence of the introduction rates of the radiation induced defects on particle and material type. The varied parameters of the silicon material are the shallow doping concentration phosphorous and the concentrations of the impurities oxygen and carbon. (orig.)

  20. Co-doped sodium chloride crystals exposed to different irradiation temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz-Morales, A. [Unidad Profesional Interdisciplinaria de Ingenieria y Tecnologias Avanzadas, IPN, Av. Instituto Politecnico Nacional 2580, Col. La Laguna Ticoman, 07340 Mexico D.F., Mexico and Unidad de Irradiacion y Segurid (Mexico); Cruz-Zaragoza, E.; Furetta, C. [Unidad de Irradiacion y Seguridad Radiologica, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, 04510 Mexico D.F (Mexico); Kitis, G. [Nuclear Physics Laboratory, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Flores J, C.; Hernandez A, J.; Murrieta S, H. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, AP. 20-364, 01000 Mexico D.F (Mexico)

    2013-07-03

    Monocrystals of NaCl:XCl{sub 2}:MnCl{sub 2}(X = Ca,Cd) at four different concentrations have been analyzed. The crystals were exposed to different irradiation temperature, such as at room temperature (RT), solid water (SW), dry ice (DI) and liquid nitrogen (LN). The samples were irradiated with photon from {sup 60}Co irradiators. The co-doped sodium chloride crystals show a complex structure of glow curves that can be related to different distribution of traps. The linearity response was analyzed with the F(D) index. The F(D) value was less than unity indicating a sub-linear response was obtained from the TL response on the function of the dose. The glow curves were deconvoluted by using the CGCD program based on the first, second and general order kinetics.

  1. DSC studies of retrogradation and amylose-lipid complex transition taking place in gamma irradiated wheat starch

    Energy Technology Data Exchange (ETDEWEB)

    Ciesla, K. [Institute of Nuclear Chemistry and Technology, Dorodna 16 str., 03-195 Warsaw (Poland)], E-mail: kciesla@orange.ichtj.waw.pl; Eliasson, A.C. [Department of Food Technology Engineering and Nutrition, Division of Food Technology, University of Lund, P.O. Box 124, S-221 00 Lund (Sweden)

    2007-12-15

    The effect of gamma irradiation ({sup 60}Co) with doses of 5-30 kGy on the amylose-lipid complex transition and retrogradation occurring in gels containing ca. 50% and ca. 20% wheat starch was studied by differential scanning calorimetry (DSC) during heating-cooling-heating cycles (up to three cycles). Transition of the amylose-lipid complex occurs in all the irradiated samples at a lower temperature as compared to the non-irradiated starch. That effect was larger when the radiation dose was higher. A further thermal treatment causes a decrease of the transition temperature in the irradiated samples, with no effect or increase of that temperature observed for the non-irradiated ones. Irradiation hinders retrogradation taking place in 50% gels but facilitates the process occurring in 20% gels. The differences between the irradiated and the non-irradiated samples are more evident in the every next heating or cooling cycle as well as after storage and in the case of ca. 50% suspensions as compared to ca. 20% suspensions. The results point out to the deterioration of the structure of the complexes formed in the irradiated starch as compared to the non-irradiated one.

  2. Variation in electrical properties of gamma irradiated cadmium selenate nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, R.P., E-mail: chauhanrpc@gmail.com; Rana, Pallavi, E-mail: prana.phy@gmail.com; Narula, Chetna; Panchal, Suresh; Choudhary, Ritika

    2016-07-15

    Preparation of low-dimensional materials attracts more and more interest in the last few years, mainly due to the wide field of potential commercial applications ranging from life sciences, medicine and biotechnology to communication and electronics. One-dimensional systems are the smallest dimension structures that can be used for efficient transport of electrons and thus expected to be critical to the function and integration of nanoscale devices. Nanowires with well controlled morphology and extremely high aspect ratio can be obtained by replicating a nanoporous polymer ion-track membrane with cylindrical pores of controlled dimensions. With this technique, materials can be deposited within the pores of the membrane by electrochemical reduction of the desired ion. In the present study, cadmium selenate nanowires were synthesized potentiostatically via template method. These synthesized nanowires were then exposed to gamma rays by using a {sup 60}Co source at the Inter University Accelerator Centre, New Delhi, India. Structural, morphological, electrical and elemental characterizations were made in order to analyze the effect of gamma irradiation on the synthesized nanowires. I–V measurements of cadmium selenate nanowires, before and after irradiation were made with the help of Keithley 2400 source meter and Ecopia probe station. A significant change in the electrical conductivity of cadmium selenate nanowires was found after gamma irradiation. The crystallography of the synthesized nanowires was also studied using a Rigaku X-ray diffractrometer equipped with Cu-Kα radiation. XRD patterns of irradiated samples showed no variation in the peak positions or phase change.

  3. Variation in electrical properties of gamma irradiated cadmium selenate nanowires

    Science.gov (United States)

    Chauhan, R. P.; Rana, Pallavi; Narula, Chetna; Panchal, Suresh; Choudhary, Ritika

    2016-07-01

    Preparation of low-dimensional materials attracts more and more interest in the last few years, mainly due to the wide field of potential commercial applications ranging from life sciences, medicine and biotechnology to communication and electronics. One-dimensional systems are the smallest dimension structures that can be used for efficient transport of electrons and thus expected to be critical to the function and integration of nanoscale devices. Nanowires with well controlled morphology and extremely high aspect ratio can be obtained by replicating a nanoporous polymer ion-track membrane with cylindrical pores of controlled dimensions. With this technique, materials can be deposited within the pores of the membrane by electrochemical reduction of the desired ion. In the present study, cadmium selenate nanowires were synthesized potentiostatically via template method. These synthesized nanowires were then exposed to gamma rays by using a 60Co source at the Inter University Accelerator Centre, New Delhi, India. Structural, morphological, electrical and elemental characterizations were made in order to analyze the effect of gamma irradiation on the synthesized nanowires. I-V measurements of cadmium selenate nanowires, before and after irradiation were made with the help of Keithley 2400 source meter and Ecopia probe station. A significant change in the electrical conductivity of cadmium selenate nanowires was found after gamma irradiation. The crystallography of the synthesized nanowires was also studied using a Rigaku X-ray diffractrometer equipped with Cu-Kα radiation. XRD patterns of irradiated samples showed no variation in the peak positions or phase change.

  4. Irradiation as a decontamination processing for rice paper sheet

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Michel M.; Thomaz, Fernanda S.; Fanaro, Gustavo B.; Duarte, Renato C.; Aquino, Simone; Villavicencio, Anna Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: villavic@ipen.br; Correa, Benedito [Universidade de Sao Paulo USP, SP (Brazil). Inst. de Ciencias Biomedicas. Dept. de Micologia]. E-mail: correabe@usp.br

    2007-07-01

    Starch is one of the most important plant products to man. The major sources of this compound for man's use are the cereals, but roots and tubers are also important. The starch industry comes in recent years growing and perfecting it self, leading to the necessity products with specific characteristics that take care the requirements of the market, it makes possible through processing raw material, still seldom explored. Rice paper sheet is an edible product derived from potatoes and rice, being commonly used to cover cakes, pies, and sweets in confectioner's shop. A microbiological control is necessary to give a high quality and to guarantee the security of this food. Irradiation would be a safe alternative as a decontamination method without adverse effects on the physical properties in the final products. The aim of this study was to investigate the best dose used as a decontamination method as well as discover the most prevalent fungi found in this product and changes on physical properties. Samples of rice paper sheet were irradiated with 2.5, 5.0 and 10.0 kGy using a {sup 60}Co irradiator. Irradiation appeared as a safe alternative as a decontamination method without adverse effects on the physical properties in the final products. (author)

  5. Production of high melt strength polypropylene by gamma irradiation

    Science.gov (United States)

    Lugão, A. B.; Artel, B. W. H.; Yoshiga, A.; Lima, L. F. C. P.; Parra, D. F.; Bueno, J. R.; Liberman, S.; Farrah, M.; Terçariol, W. R.; Otaguro, H.

    2007-11-01

    High melt strength polypropylene (HMS-PP) has been recently developed and introduced in the market by the major international producers of polypropylene. Therefore, BRASKEM, the leading Brazilian PP producer, together with EMBRARAD, the leading Brazilian gamma irradiator, and the IPEN (Institute of Nuclear Energy and Research) worked to develop a national technology for the production of HMS-PP. One of the effective approaches to improve melt strength and extensibility is to add chain branches onto polypropylene backbone using gamma radiation. Branching and grafting result from the radical combinations during irradiation process. Crosslinking and main chain scission in the polymer structure are also obtained during this process. In this work, gamma irradiation technique was used to induce chemical changes in commercial polypropylene with two different monomers, Tri-allyl-isocyanurate (TAIC) and Tri-methylolpropane-trimethacrylate (TMPTMA), with concentration ranging from 1.5 to 5.0 mmol/100 g of polypropylene. These samples were irradiated with a 60Co source at dose of 20 kGy. It used two different methods of HMS-PP processing. The crosslinking of modified polymers was studied by measuring gel content melt flow rate and rheological properties like melt strength and drawability. It was observed that the reaction method and the monomer type have influenced the properties. However, the concentration variation of monomer has no effect.

  6. Evaluating the effect of gamma radiation ({sup 60}Co) on protein arcelin and its influence in the resistance of Zabrotes subfasciatus (Boh., 1833) (Coleoptera: Bruchidae); Avaliacao do efeito da radiacao gama ({sup 60}Co) sobre a proteina arcelina e sua influencia na resistencia a Zabrotes subsfasciatus (Boh., 1833) (Coleoptera: Bruchidae)

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Valeria Wanderley

    1998-07-01

    The objective of this research was to evaluate the effects of different gamma doses of Cobalt-60 on arcelin protein in the manifestation of resistance to Zabrotes subfasciatus (Boh., 1833). Seeds of four lines of Phaseolus vulgaris carriers of arcelin protein (Arcelin-1, Arcelin-2, Arcelin-3 and Arcelin-4) and a cultivar without this protein were used as control (IAC-Carioca Akyta) obtained from the Instituto Agronomico do Estado de Sao Paulo - Nucleo Experimental de Campinas (IAC), were irradiated in a source of Cobalt-60, of the panoramic type, from the Instituto de Pesquisas Energeticas e Nucleares/CNEN/SP. The activity was approximately 2218.79 Ci, and the dose rate 0.678 kGy/h. The doses used were 0; 0.25; 0.5; 1.0 and 2.0 kGy. The results showed that the radiation doses did not influence the parameters evaluated in the resistance because a high degree of antibiose in the Arcelin-1 and Arcelin-2 lines was maintained. The Arcelin-3 and Arcelin-4 lines also maintained their behavior less expressive of resistance by antibiose only prolonging the period from egg to adult. The electrophoretic analysis of the lines and cultivar were not changed in relation to the radiation doses. But there was a decrease in relation to the intensity of color of the bands (absorbance) with the increase of the doses. (author)

  7. Protective effect of poly ({alpha}-L-glutamate) against UV and {gamma}-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu E-mail: mfuruta@riast.osakafu-u.ac.jp; Huy, Nguyen Quang; Tsuchiya, Akihito; Nakatsuka, Hiroshige; Hayashi, Toshio

    2004-10-01

    We occasionally found that poly ({alpha}-L-glutamate) showed a superior protective effect on enzymes against UV and {sup 60}Co-{gamma} irradiation. We selected papain and {alpha}-amylase as a model enzyme and irradiated the aqueous solution (10 mg/ml) of each enzyme with UV and {sup 60}Co-{gamma} rays in the presence of poly ({alpha}-L-glutamate) ({alpha}-PGA), poly (glucosyl oxyethyl methacrylate (GEMA)), and glucose (1.25% w/v each). The mixture of the three compounds has a significant protective effect on the activity of papain solution showing 40% of remaining activity twice as much as the control containing no additive at the dose of 15 kGy. Among them, {alpha}-PGA showed the highest protecting effect on the both papain and {alpha}-amylase even after 10-kGy irradiation at which 50% of the activity was retained. {alpha}-PGA also showed significant protective activity on {alpha}-amylase against UV both in solution and under dried state.

  8. Low-power laser irradiation did not stimulate breast cancer cells following ionizing radiation

    Science.gov (United States)

    Silva, C. R.; Camargo, C. F. M.; Cabral, F. V.; Ribeiro, M. S.

    2016-03-01

    Cancer has become a public health problem worldwide. Radiotherapy may be a treatment to a number of types of cancer, frequently using gamma-radiation with sources such as 137Cs and 60Co, with varying doses, dose rates, and exposure times to obtain a better as a stimulant for cell proliferation and tissue healing process. However, its effects on cancer cells are not yet well elucidated. The purpose of this work was to evaluate the effects of the LPL on breast cancer cultures after ionizing radiation. The breast cancer-MDA-MB-231 cells were gamma irradiated by a 60Co source, with dose of 2.5 Gy. After 24h, cells were submitted to LPL irradiation using a red laser emitting at λ= 660 nm, with output power of 40 mW and exposure time of 30 s and 60 s. The plates were uniformly irradiated, with energy of 1.2 J and 2.4 J, respectively. Cell viability was analyzed using the exclusion method with trypan blue. Our results show that breast cancer cells submitted to LPL after ionizing radiation remained 95 % viable. No statistically significant differences were observed between laser and control untreated cells, (P > 0.05). These findings suggest that LPL did not influenced cancer cells viability.

  9. Protection of negative gravitaxis in Euglena gracilis Z against gamma-ray irradiation by Trolox C

    Energy Technology Data Exchange (ETDEWEB)

    Sakashita, Tetsuya; Doi, Masahiro; Yasuda, Hiroshi; Fuma, Shoichi [National Inst. of Radiological Sciences, Chiba (Japan). Research Center for Radiation Safety; Hader, D.P. [Biologie der Friedrich-Alexander Univ., Erlangen (Germany). Inst. fuer Botanik und Pharmazeutische Biologie

    2002-12-01

    The protective effects of Trolox on the inhibition of negative gravitaxis in Euglena gracilis exposed to 200 Gy {sup 60}Co gamma-rays were examined using different concentrations (1, 10 and 100 {mu}M). The orientation precision of the negative gravitaxis was quantified using the r-value. A significant decrease in the r-value was observed in gamma-irradiated samples (0.18+/-0.03) compared to those of non-irradiated samples (0.47+/-0.03). There were no significant changes in the r-value of cells exposed to 200 Gy gamma-rays by the addition of 1 or 10 {mu}M of Trolox. A significant increase (0.19) in the r-value of cells exposed to 200 Gy with 100 {mu}M Trolox was observed. The results indicates that Trolox at a concentration of 100 {mu}M protects negative gravitaxis against {sup 60}Co gamma-ray irradiation at a dose of 200 Gy. It also suggests that the negative gravitaxis of Euglena gracilis is affected by free radicals.(author)

  10. Inactivation of mildew in rough rice and wheat by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jun, E-mail: jwang@zju.edu.c [Department of Biosystems Engineering, Zhejiang University, 268 Kaixuan Road, Hangzhou 310029 (China); Yu Yong [Department of Biosystems Engineering, Zhejiang University, 268 Kaixuan Road, Hangzhou 310029 (China)

    2010-06-15

    Rough rice and wheat were irradiated by gamma ray ({sup 60}Co) with different doses and the mildew inactivation efficacy was investigated after 0, 6 and 12 month storage. Five genera of mildew in rough rice and wheat were detected, including Alternaria, Fusarium, Aspergillus, Penicillium and Rhizopus. For Aspergillus, four genera of mold were detected, including Aspergillus Kawachii, Aspergillus glaucus, Aspergillus niger, Aspergillus flavus. Detection rates of the five genera of mildew and four genera of Aspergillus were all reduced with increasing dose after 0, 6 and 12 months storage. The detection rates of the other four genera of mildew had no significant change during storage.

  11. Action of Bothrops moojeni venom and its L-amino acid oxidase fraction, treated with {sup 60}Co gamma rays, in Leishmania spp; Acao do veneno de Bothrops moojeni e sua fracao L-aminoacido oxidase, submetida ao tratamento com raios gama de {sup 60}Co, em Leishmania spp

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Andre Gustavo Tempone

    1999-07-01

    Bothrops moojeni venom showed an anti leishmania activity in vitro, as determined by a cell viability assay using the reduction of MTT. After venom purification, by chromatography techniques, the fractions with anti leishmania and L-amino acid oxidase activities, eluted in the same positions. The molecular weight of the enzyme was estimated to be 140 kDa by molecular exclusion chromatography, and 69 kDa, by SDS-PAGE, migrating as a single band, with an isoelectric point of 4.8 as determined by isoelectric focusing. The purified LAO from B. moojeni venom, 135-fold more active than crude venom, showed homo dimeric constitution, and was active against Leishmania spp from the New World, with an effective concentration against L(L). amazonensis of 1.80 {mu}g/ml (EC{sub 50}), L.(V.) panamensis (0.78 |{mu}g/ml) and L.(L.) chagasi (0.63 ({mu}g/ml). Ultrastructural studies of promastigotes affected by LAO demonstrated cell death, with edema in several organelles such as mitochondria and nuclear membrane, before cell disruption and necrosis. The action of LAO was demonstrated to be hydrogen peroxide-dependent. Studies with LLCMK-2 cells, treated with LAO, showed a toxic effect, with an EC{sub 50} of 11|{mu}g/ml. Irradiation of LAO with 6{sup 0C}o gamma rays, did not affect its whole oxidative activity, neither detoxified the enzyme. Amastigotes treated with LAO were not affected by its hydrogen peroxide, otherwise, the exogenous product, killed amastigotes with an EC{sub 50} of 0.67mM. These data could be of help in the development of alternative therapeutic approaches to the treatment of leishmaniasis. (author)

  12. Characteristics of non-irradiated and irradiated double SOI integration type pixel sensor

    Science.gov (United States)

    Asano, M.; Sekigawa, D.; Hara, K.; Aoyagi, W.; Honda, S.; Tobita, N.; Arai, Y.; Miyoshi, T.; Kurachi, I.; Tsuboyama, T.; Yamada, M.

    2016-09-01

    We are developing monolithic pixel sensors based on a 0.2 μm fully depleted silicon-on-insulator (FD-SOI) technology for high-energy physics experiment applications. With this SOI technology, the wafer resistivities for the electronics and sensor parts can be chosen separately. Therefore, a device with full depletion and fast charge collection is realized. The total ionizing dose (TID) effect is the major challenge for application in hard radiation environments. To compensate for TID damage, we introduced a double SOI structure that implements an additional middle silicon layer (SOI2 layer). Applying a negative voltage to the SOI2 layer should compensate for the effects induced by holes trapped in the buried oxide layers. We studied the recovery from TID damage induced by 60Co γ and other characteristics of the integration-type double SOI sensor INTPIXh2. When the double SOI sensor was irradiated to 100 kGy, it showed a response to the infrared laser similar to that of a non-irradiated sensor when we applied a negative voltage to the SOI2 layer. Thus, we concluded that the double SOI sensor is very effective at sufficiently enhancing the radiation hardness for application in experiments with harsh radiation environments, such as at Belle II or ILC.

  13. Characteristics of non-irradiated and irradiated double SOI integration type pixel sensor

    Energy Technology Data Exchange (ETDEWEB)

    Asano, M.; Sekigawa, D. [Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8751 (Japan); Hara, K., E-mail: hara@hep.px.tsukuba.ac.jp [Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8751 (Japan); Center for Integrated Research in Fundamental Science and Engineering, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan); Aoyagi, W.; Honda, S.; Tobita, N. [Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8751 (Japan); Arai, Y.; Miyoshi, T.; Kurachi, I.; Tsuboyama, T.; Yamada, M. [Institute of Particle and Nuclear Study, KEK, Oho 1-1, Tsukuba, Ibaraki 305-0801 (Japan)

    2016-09-21

    We are developing monolithic pixel sensors based on a 0.2 μm fully depleted silicon-on-insulator (FD-SOI) technology for high-energy physics experiment applications. With this SOI technology, the wafer resistivities for the electronics and sensor parts can be chosen separately. Therefore, a device with full depletion and fast charge collection is realized. The total ionizing dose (TID) effect is the major challenge for application in hard radiation environments. To compensate for TID damage, we introduced a double SOI structure that implements an additional middle silicon layer (SOI2 layer). Applying a negative voltage to the SOI2 layer should compensate for the effects induced by holes trapped in the buried oxide layers. We studied the recovery from TID damage induced by {sup 60}Co γ and other characteristics of the integration-type double SOI sensor INTPIXh2. When the double SOI sensor was irradiated to 100 kGy, it showed a response to the infrared laser similar to that of a non-irradiated sensor when we applied a negative voltage to the SOI2 layer. Thus, we concluded that the double SOI sensor is very effective at sufficiently enhancing the radiation hardness for application in experiments with harsh radiation environments, such as at Belle II or ILC.

  14. Late effects of total-head gamma irradiation in mice. 2. Pathomorphological analysis of organic changes with regard to the role of the hypophysis - adrenal gland axis and of the thymolymphatic system

    Energy Technology Data Exchange (ETDEWEB)

    Tkadlecek, L.; Viklicka, S.; Karpfel, Z.; Pospisil, M.; Netikova, J. (Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav)

    1985-01-01

    Relations between late manifestations of wasting of C57BL/10 mice whose heads were irradiated with a dose of 16 Gy of /sup 60/Co gamma rays, and some pathomorphological findings in the organs of animals in the late period after irradiation were studied. A close correlation was found between the fall in body weight of animals during the period of the 6th month after irradiation and involution of the thymolymphatic system. Adenohypophysis and adrenal cortex of wasting animals revealed clear signs of structural defects, indicating failure of their hormonal functions. Morphological examination of brain, cerebellum, duodenum and liver did not exhibit signs of damage.

  15. The Exploration of Stereoscopic Imaging Technique in Dual View 60 Co Container Inspection System%双视角60Co集装箱检测系统中立体成像技术

    Institute of Scientific and Technical Information of China (English)

    薛岳; 苗积臣; 吴志芳; 邢桂来

    2014-01-01

    为了克服传统集装箱检测系统难以辨别前后重叠在一起的物体的缺点,双视角60 Co集装箱检测系统将立体成像技术应用在传统的检测系统中。双视角立体成像与分析是系统的核心技术之一,通过研究与比对不同的立体成像方式,针对系统的不同终端,分别应用色分法和时差分像法将系统从不同视角获得的图像分别传送至检测人员的左右眼,使其在大脑中融合成一幅立体图像。论文设计的双视角60 Co集装箱检测系统实现了对集装箱等大型客体的立体成像检测,不仅可以对前后重叠的物体进行有效区分,而且可以生成客体的三维影像,提高了系统的检测效果。%In traditional container inspection system, projection of different objects will overlap, making it diffi-cult to distinguish between them.In order to overcome this shortcoming, stereoscopic imaging is applied in the Binocular 60 Co container inspection system.The binocular stereoscopic imaging is one of the core technologies in the system.By studying and comparing different ways of stereoscopic imaging, according to different termi-nals of the system, anaglyph method and time-sequential method are respectively applied to transmit the image gained from different perspective to the corresponding eye of the inspector, generating stereoscopic image in the brain.The Binocular 60 Co container inspection system designed in this paper implements the stereoscopic image inspection for the containers and other large objects.This system is able to distinguish overlapping objects effec-tively, and detection effectiveness is improved through the stereoscopic image of the objects.

  16. Optical properties of CsI single crystals irradiated with neutrons at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Okada, M. [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.; Nakagawa, M. [Faculty of Education, Kagawa Univ., Takamatsu, Kagawa (Japan); Atobe, K. [Faculty of Science, Naruto Univ. of Education, Naruto, Tokushima (Japan); Itatani, N.; Ozawa, K. [Horiba Ltd., Minamiku, Kyoto (Japan)

    1998-05-01

    Optical properties of the irradiation-induced-defects in neutron-irradiated CsI single crystals have been investigated. The nominally pure CsI crystals are irradiated by reactor fast neutrons (E>0.1 MeV) with a fluence of 1.4 x 10{sup 15} n/cm{sup 2} at 20 K and by {gamma}-rays from {sup 60}Co source to a dose of 1.5 x 10{sup 4} Gy at liquid nitrogen temperature (LNT). After the irradiations, isochronal annealings are performed to investigate the thermal behavior of the defects. The glow peaks of the thermoluminescence (TL) in each sample irradiated with neutrons at 20 K and with {gamma}-rays at LNT are observed at about 100, 160 and 220 K. In the neutron-irradiated samples at 20 K, the emission band at 338 nm is observed at LNT. It is supposed that this emission band occurs by an excitation of {gamma}-rays from {sup 134}Cs, which is radioactivated by thermal neutrons among the reactor radiations. It is confirmed that the temperature dependence of the 338 nm band is similar with that of the emission band due to the self-trapped exciton which is introduced into the non-irradiated samples illuminated by higher energy photons. (orig.) 13 refs.

  17. Effect of γ-irradiation in the keeping quality of Nigerian onion cultivars

    Science.gov (United States)

    Agbaji, A. S.; Ogbadu, G. H.; Van Amstel, H.

    Onion of variety Ds × Ws'78 and Ds'79 harvested 14 days prior to the experiment were treated with 5, 8 and 15 krad doses of γ-irradiation from a 60Co γ-irradiator. Bulbs were stored in a well ventilated room at ambient temperature (20-25°C) and RH 20-82% in vegetable mesh bags on wooden shelves for 7 months. Onions were weekly investigated for sprouting and rotting. Chemical analyses were carried out monthly for dry matter, flavour, ascorbic acid, reducing sugar and protein. In comparison, a local method of storage was carried out. Irradiation dose of 5-15 krad completely inhibited sprouting throughout the whole storage period. Irradiated bulbs however, showed a higher tendency to rot. In comparison with the control, irradiation did not have any significant effect on dry matter, flavour component and ascorbic acid but the protein content was significantly lower in the irradiated bulbs. The compositional differences found between irradiated and untreated onions seem to be of no nutritional or organoleptic significance. Almost 100% loss was recorded for local storage trial.

  18. Irradiation treatment for the protection and conservation of cultural heritage artefacts in Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Katusin-Razem, Branka [Department of Chemistry, Ruder Boskovic Institute, Bijenicka cesta 54, P.O. Box 180, HR-10002 Zagreb (Croatia)], E-mail: brazem@irb.hr; Razem, Dusan [Department of Chemistry, Ruder Boskovic Institute, Bijenicka cesta 54, P.O. Box 180, HR-10002 Zagreb (Croatia); Braun, Mario [Croatian Conservation Institute, Zagreb (Croatia)

    2009-07-15

    The application of irradiation treatment for the protection of cultural heritage artefacts in Croatia was made possible by the development of radiation processing procedures at the Radiation Chemistry and Dosimetry Laboratory of the Ruder Boskovic Institute. After the upgrading of the {sup 60}Co gamma irradiation source in the panoramic irradiation facility in 1983 it became possible to perform both research and pilot plant-scale irradiations for sterilization, pasteurization and decontamination of various materials, including medical supplies, pharmaceuticals, cosmetics and foods, but also for disinfestation of cultural heritage artefects. The demand for irradiation treatment of cultural heritage objects has particularly increased as the increasing number of these objects, especially polychromic wooden sculptures, were requiring salvation, restauration and conservation as a consequence of direct and indirect damages inflicted to them during the war in Croatia, 1991-1995. The irradiation facility at the Ruder Boskovic Institute is briefly described and an account of its fifteen years' activities in the irradiation treatment of cultural heritage objects is given. Some case studies performed in cooperation with the Croatian Conservation Institute and other interested parties are presented, as well as some cases of protective and curative treatments for disinfestation and decontamination. International cooperations and activities are also mentioned.

  19. Laboratory longevity and competitiveness of Dacus ciliatus Loew (Diptera: Tephritidae) following sub-sterilizing gamma irradiation.

    Science.gov (United States)

    Nemny-Lavy, E; Nestel, D; Rempoulakis, P

    2016-06-01

    The effect of a sub-sterilizing gamma radiation dose on Dacus ciliatus adults was investigated to assess the suitability of the sterile insect technique (SIT) as an alternative method to control this pest. Late pupae (48 h prior to adult emergence) from a laboratory strain were irradiated with 120 Gy of gamma rays emitted by a 60Co source. Following adult emergence, the mortality of irradiated and non-irradiated cohorts was recorded. Over a period of 50 days after emergence, no significant negative effects of irradiation upon the longevity of male or female laboratory flies were observed. A laboratory competitiveness study (Fried test), using irradiated laboratory and wild males at a ratio of 3:1 was conducted to assess the ability of irradiated males to reduce the egg hatch rates of a wild population. The overall competitiveness was found to be ca. 0.32, suggesting a reduced, but satisfactory, quality of irradiated laboratory as compared with wild males. Based on the above findings, we calculated and proposed effective male release ratios for field application of SIT against D. ciliatus.

  20. Application of different techniques to identify the effects of irradiation on Brazilian beans after six months storage

    Energy Technology Data Exchange (ETDEWEB)

    Villavicencio, A.L.C.H.; Mancini-Filho, J.; Delincee, H

    1998-06-01

    Four different techniques to detect the effect of irradiation in beans were investigated. Two types of Brazilian beans, Phaseolus vulgaris L., var. carioca and Vigna unguiculata (L.) Walp, var. macacar, were irradiated using a {sup 60}Co source with doses ranging from 0, 1.0 to 10.0 kGy. After 6 months storage at ambient temperature the detection tests were carried out. Firstly, germination tests showed markedly reduced root growth and almost totally retarded shoot elongation of irradiated beans as compared to non-irradiated beans. Secondly, DNA fragmentation was studied using a microgel electrophoresis. Irradiated cells produced typical comets with DNA fragments migrating towards the anode. DNA of non-irradiated cells exhibited a limited migration. Thirdly, electron spin resonance for detection of cellulose radicals was tested, since it was expected that these free radicals are quite stable in solid and dry foods. However, only in beans irradiated with 10 kGy a small signal could be detected. Fourthly, thermoluminescence, a method to analyze mineral debris adhering to food, turned out to be a good choice to detect irradiation effects in beans, even after 6 months of storage. The results indicate that three of these four techniques proposed, can be used to detect the effect of irradiation in these two varieties of Brazilian beans at a dose level useful for insect disinfestation (1 kGy)

  1. Application of different techniques to identify the effects of irradiation on Brazilian beans after six months storage

    Science.gov (United States)

    Villavicencio, A. L. C. H.; Mancini-Filho, J.; Delincée, H.

    1998-06-01

    Four different techniques to detect the effect of irradiation in beans were investigated. Two types of Brazilian beans, Phaseolus vulgaris L., var. carioca and Vigna unguiculata (L.) Walp, var. macaçar, were irradiated using a 60Co source with doses ranging from 10.0 kGy. After 6 months storage at ambient temperature the detection tests were carried out. Firstly, germination tests showed markedly reduced root growth and almost totally retarded shoot elongation of irradiated beans as compared to non-irradiated beans. Secondly, DNA fragmentation was studied using a microgel electrophoresis. Irradiated cells produced typical comets with DNA fragments migrating towards the anode. DNA of non-irradiated cells exhibited a limited migration. Thirdly, electron spin resonance for detection of cellulose radicals was tested, since it was expected that these free radicals are quite stable in solid and dry foods. However, only in beans irradiated with 10 kGy a small signal could be detected. Fourtly, thermoluminescence, a method to analyze mineral debris adhering to food, turned out to be a good choice to detect irradiation effects in beans, even after 6 months of storage. The results indicate that three of these four techniques proposed, can be used to detect the effect of irradiation in these two varieties of Brazilian beans at a dose level useful for insect disinfestation (1 kGy).

  2. Detection of irradiated onion by means of the comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Alvarez, Damaris L.; Prieto Miranda, Enrique Fco.; Carro Palacio, Sandra [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear. (CEADEN), Ciudad de La Habana (Cuba)]. E-mail: damaris@ceaden.edu.cu; efprieto@ceaden.edu.cu; Iglesia Enriquez, Isora [Instituto de Investigacion para la Industria Alimenticia (IIIA), Ciudad de La Habana (Cuba)

    2007-07-01

    The ionizing radiations are used as a harmless alternative treatment that it substitutes the employment of chemical treatments, which after their application in the food products can remain residuals not desired that they come to be carcinogenic. With the food irradiation is eliminated microorganisms and the storage time is prolonged, which produces benefits for the Food Industry and the consumers. In many countries the search of sensitive detecting methods of irradiated foods is promoted by the necessity of the assurance of the consumption of foods with nutritional quality and to test directly the radiation processing, for which several techniques have been developed, these are based on the changes that induce the ionizing radiations in the food products. A recommended method is the Comet Assay of DNA, it is approved by the European Committee of Standardization (EN 13784). The DNA molecule is very sensitive to gamma radiations even at low radiation dose, where the modifications produced in the molecule can be monitored for this analytical technique well-known as Comet Assay of DNA or Single Cell Gel Electrophoresis. The objective of the present paper was to evaluate the modifications of the DNA molecule of irradiated onions with the Comet Assay for several dose values, the onions were conserved at environment and refrigeration temperatures. The samples were irradiated in a self-shielding irradiator with {sup 60}Co source, dose rate of 20.45 Gy/min and absorbed dose values of 0.5; 0.6; 0.8 and 1.0 kGy. This detection method demonstrates to be one sensitive and quick technique for the qualitative detection of irradiated onions. (author)

  3. Effects of high dose gamma irradiation on ITO thin film properties

    Energy Technology Data Exchange (ETDEWEB)

    Alyamani, A. [National Nanotechnology Center, King Abdul-Aziz City for Science and Technology (KACST), Riyadh (Saudi Arabia); Mustapha, N., E-mail: nazirmustapha@hotmail.com [Dept. of Physics, College of Sciences, Al Imam Mohammad Ibn Saud Islamic University, P.O. Box 90950, Riyadh 11623 (Saudi Arabia)

    2016-07-29

    Transparent thin-film Indium Tin Oxides (ITO) were prepared on 0.7 mm thick glass substrates using a pulsed laser deposition (PLD) process with average thickness of 150 nm. The samples were then exposed to high gamma γ radiation doses by {sup 60}Co radioisotope. The films have been irradiated by performing exposure cycles up to 250 kGy total doses at room temperature. The surface structures before and after irradiation were analysed by x-ray diffraction. Atomic Force Microscopy (AFM) was performed on all samples before and after irradiation to investigate any change in the grain sizes, and also in the roughness of the ITO surface. We investigated the influence of γ irradiation on the spectra of transmittance T, in the ultraviolet-visible-near infrared spectrum using spectrophotometer measurements. Energy band gap E{sub g} was then calculated from the optical spectra for all ITO films. It was found that the optical band gap values decreased as the radiation dose was increased. To compare the effect of the irradiation on refractive index n and extinction coefficient k properties, additional measurements were done on the ITO samples before and after gamma irradiation using an ellipsometer. The optical constants n and k increased by increasing the irradiation doses. Electrical properties such as resistivity and sheet resistance were measured using the four-point probe method. The good optical, electrical and morphological properties maintained by the ITO films even after being exposed to high gamma irradiation doses, made them very favourable to be used as anodes for solar cells and as protective coatings in space windows. - Highlights: • Indium Tin Oxide (ITO) thin films were deposited by pulsed laser deposition. • Effects of Gamma irradiation were investigated. • Changes of optical transmission and electrical properties of ITO films were studied. • Intensity of the diffraction peaks and the film's structure changed with increasing irradiation doses.

  4. Key comparison BIPM.RI(I)-K4 of the absorbed dose to water standards of the LNE-LNHB, France and the BIPM in 60Co gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D. T.; Delaunay, F.; Donois, M.

    2013-01-01

    An indirect comparison has been made of the standards for absorbed dose to water in 60Co radiation of the Laboratoire National de Métrologie et d'Essais-Laboratoire National Henri Becquerel (LNE-LNHB), France and of the Bureau International des Poids et Mesures (BIPM). The measurements at the BIPM were carried out in April 2013. The comparison result, based on the calibration coefficients for two transfer standards and evaluated as a ratio of the LNE-LNHB and the BIPM standards for absorbed dose to water, is 0.9971 with a combined standard uncertainty of 3.9 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  5. Microdosimetry of DNA conformations: relation between direct effect of (60)Co gamma rays and topology of DNA geometrical models in the calculation of A-, B- and Z-DNA radiation-induced damage yields.

    Science.gov (United States)

    Semsarha, Farid; Raisali, Gholamreza; Goliaei, Bahram; Khalafi, Hossein

    2016-05-01

    In order to obtain the energy deposition pattern of ionizing radiation in the nanometric scale of genetic material and to investigate the different sensitivities of the DNA conformations, direct effects of (60)Co gamma rays on the three A, B and Z conformations of DNA have been studied. For this purpose, single-strand breaks (SSB), double-strand breaks (DSB), base damage (BD), hit probabilities and three microdosimetry quantities (imparted energy, mean chord length and lineal energy) in the mentioned DNA conformations have been calculated and compared by using GEometry ANd Tracking 4 (Geant4) toolkit. The results show that A-, B- and Z-DNA conformations have the highest yields of DSB (1.2 Gy(-1) Gbp(-1)), SSB (25.2 Gy(-1) Gbp(-1)) and BD (4.81 Gy(-1) Gbp(-1)), respectively. Based on the investigation of direct effects of radiation, it can be concluded that the DSB yield is largely correlated to the topological characteristics of DNA models, although the SSB yield is not. Moreover, according to the comparative results of the present study, a reliable candidate parameter for describing the relationship between DNA damage yields and geometry of DNA models in the theoretical radiation biology research studies would be the mean chord length (4 V/S) of the models.

  6. Relative biological effectiveness of fission neutrons for producing micronuclei in the root-tip cells of onion seedlings after irradiation as dry seeds

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, W.; Ishikawa, Masayori; Hoshi, Masaharu [Hiroshima Univ. (Japan). Research Inst. for Radiation Biology and Medicine; Endo, Satoru [Hiroshima Univ., Higashi-Hiroshima (Japan). Graduate School of Engineering; Ikeda, Hideo [Hiroshima Univ., Higashi-Hiroshima (Japan). Faculty of Education

    2002-12-01

    The relative biological effectiveness (RBE) of mixed neutron and gamma-ray radiation emitted at a {sup 252}Cf source at the Research Institute for Radiation Biology and Medicine, Hiroshima University, compared with {sup 60}Co gamma-ray radiation was determined. The tissue-absorbed dose contribution of the accompanying gamma radiation was about 35.7% to the total tissue-absorbed dose from the {sup 252}Cf mixed radiation. The {sup 252}Cf mixed radiation and {sup 60}Co gamma rays produced approximate linear changes in the frequency of micronuclei induced in root-tip cells of Allium cepa L. onion seedlings after irradiation as dry dormant seeds with varying absorbed doses in onion seeds. Therefore, the RBE for radiation-induced micronuclei was calculated as the ratio of the slopes for the {sup 252}Cf mixed radiation and the {sup 60}Co gamma rays. The deduced RBE value of {sup 252}Cf mixed radiation of {sup 60}Co gamma rays to induce micronuclei in dry dormant onion seed cells was about 90.5{+-}3.6 ({+-}1{sigma}); the RBE of neutrons from the {sup 252}Cf mixed radiation was about 150{+-}6 ({+-}1{sigma}). Furthermore, the sensitivity ratio of the induction rate of micronuclei in dry dormant seeds to that in seedlings by neutrons from {sup 252}Cf mixed radiation was significantly different from that by {sup 60}Co gamma rays. From these results, we concluded that the repair efficiency of DNA damage induced by neutrons may be different from that by gamma rays. (author)

  7. Long-term follow-up study on reproductive and endocrine function in six victims accidentally exposed to 60 Co radiation%6名钴-60源辐射事故受照者生殖及内分泌功能远期效应随访

    Institute of Scientific and Technical Information of China (English)

    赵凤玲; 傅宝华; 吕玉民; 吴艳延; 邢志伟; 姜恩海; 姜梅玲; 于程程

    2014-01-01

    and endocrine function was performed in six victims exposed to the April 26 60 Co radiation accident in Henan province in 1999.1) Obstetrical history and female menstrual history were particularly inquired;2) the morphology and size of thyroid gland , uterus and ovary were examined via color Doppler ultrasound; 3 ) the level of reproductive hormone, thyroid function, and semen routine of male were detected in the radiation accident victims .Results Case Mei, a 38-year-old married female, was observed the amenorrhea induced by radiation 2 years after the exposure .And the obvious shrinkage of uterine and ovarian size , the significantly decreasing sex hormones levels of estradiol and progesterone, and the obviously increasing follicle-stimulating hormone (FSH) and luteinizing hormone (LH), were all found 2 years after the irradiation in the victim .Case Wang, an 8-year-old boy, of whom the development of reproductive organ, semen routine and reproductive hormone levels were all normal after radiation , and a healthy infant boy was born after his marriage.Case Tian, Yong, Min and Yi, were four adult males, of whom no significant change was observed in sexual desire after exposure , but their sperm counts and sperm motility significantly decreased 3 months after the radiation . The sperm number further fell to zero 6 months and 12 months later , and gradually began to recover 2 years after the radiation.Reproductive testosterone hormone levels were all at normal range in the four adult male victims , but the levels of temporarily elevated FSH in Tian , Min and Yi while the levels of temporarily elevated LH in Min were detected 1 year after the exposure .There were 5 victims examined by color Doppler ultrasound 15 years after radiation , Mei Tian and Min were diagnosed as the thyroid nodule , while Wang and Yi were normal .Higher levels of thyroid stimulating hormone (TSH) in Mei were observed at year 11, 13, and 15 after irradiation, while T3 and T4 were normal, and

  8. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Science.gov (United States)

    Alberti, Angelo; Chiaravalle, Eugenio; Fuochi, Piergiorgio; Macciantelli, Dante; Mangiacotti, Michele; Marchesani, Giuliana; Plescia, Elena

    2011-12-01

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy.We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with 60Co γ-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO2-, CO33-, SO2- and SO3- radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters.

  9. Identification of irradiated wheat by germination test, DNA comet assay and electron spin resonance

    Science.gov (United States)

    Barros, Adilson C.; Freund, Maria Teresa L.; Villavicencio, Ana Lúcia C. H.; Delincée, Henry; Arthur, Valter

    2002-03-01

    In several countries, there has been an increase in the use of radiation for food processing thus improving the quality and sanitary conditions, inhibiting pathogenic microorganisms, delaying the natural aging process and so extending product lifetime. The need to develop analytical methods to detect these irradiated products is also increasing. The goal of this research was to identify wheat irradiated using different radiation doses. Seeds were irradiated with a gamma 60Co source (Gammacell 220 GC) in the Centro de Energia Nuclear na Agricultura and the Instituto de Pesquisas Energéticas e Nucleares. Dose rate used were 1.6 and 5.8kGy/h. Applied doses were 0.0, 0.10, 0.25, 0.50, 0.75, 1.0, and 2.0kGy. After irradiation, seeds were analysed over a 6 month period. Three different detection methods were employed to determine how irradiation had modified the samples. Screening methods consisted of a germination test measuring the inhibition of shooting and rooting and analysis of DNA fragmentation. The method of electron spin resonance spectroscopy allowed a better dosimetric evaluation. These techniques make the identification of irradiated wheat with different doses possible.

  10. Gamma irradiator dose mapping: a Monte Carlo simulation and experimental measurements

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Rogerio R.; Ribeiro, Mariana A.; Grynberg, Suely E.; Ferreira, Andrea V.; Meira-Belo, Luiz Claudio, E-mail: rrr@cdtn.b, E-mail: marianaalmeida@ufmg.b, E-mail: seg@cdtn.b, E-mail: avf@cdtn.b, E-mail: lcmb@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Sousa, Romulo V.; Sebastiao, Rita de C.O., E-mail: romuloverdolin@yahoo.com.b, E-mail: ritacos@ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Inst. de Ciencias Exatas. Dept. de Quimica

    2009-07-01

    Gamma irradiator facilities can be used in a wide range of applications such as biological and chemical researches, food treatment and sterilization of medical devices and products. Dose mapping must be performed in these equipment in order to establish plant operational parameters, as dose uniformity, source utilization efficiency and maximum and minimum dose positions. The isodoses curves are generally measured using dosimeters distributed throughout the device, and this procedure often consume a large amount of dosimeters, irradiation time and manpower. However, a detailed curve doses identification of the irradiation facility can be performed using Monte Carlo simulation, which reduces significantly the monitoring with dosimeters. The present work evaluates the absorbed dose in the CDTN/CNEN Gammacell Irradiation Facility, using the Monte Carlo N-particles (MCNP) code. The Gammacell 220, serial number 39, was produced by Atomic Energy of Canada Limited and was loaded with sources of {sup 60}Co. Dose measurements using TLD and Fricke dosimeters were also performed to validate the calculations. The good agreement of the results shows that Monte Carlo simulations can be used as a predictive tool of irradiation planning for the CDTN/CNEN Gamma Cell Irradiator. (author)

  11. Effect of gamma irradiation on the behavioral properties of crotoxin

    Directory of Open Access Journals (Sweden)

    E.G. Moreira

    1997-02-01

    Full Text Available Crotoxin has been detoxified with gamma radiation in order to improve crotalic antiserum production. Nevertheless, present knowledge of the biological characteristics of irradiated crotoxin is insufficient to propose it as an immunizing agent. Crotoxin is known to increase the emotional state of rats and to decrease their exploratory behavior (Moreira EG, Nascimento N, Rosa GJM, Rogero JR and Vassilieff VS (1996 Brazilian Journal of Medical and Biological Research, 29: 629-632. Therefore, we decided 1 to evaluate the effects of crotoxin in the social interaction test, which has been widely used for the evaluation of anxiogenic drugs, and 2 to determine if irradiated crotoxin induces behavioral alterations similar to those of crotoxin in the social interaction, open-field and hole-board tests. Male Wistar rats (180-220 g were used. Crotoxin (100, 250, and 500 µg/kg was injected intraperitoneally 2 h before the social interaction test. Similarly, irradiated crotoxin (2000 Gy gamma radiation from a 60Co source was administered at the doses of 100, 250, and 500 µg/kg for the hole-board test, and at the doses of 1000 and 2500 µg/kg for the open-field and social interaction tests. ANOVA complemented with the Dunnett test was used for statistical analysis (P<0.05. Crotoxin decreased the social interaction time (s at the doses of 100, 250 and 500 µg/kg (means ± SEM from 51.6 ± 4.4 to 32.6 ± 3.7, 28.0 ± 3.6 and 31.6 ± 4.4, respectively. Irradiated crotoxin did not induce behavioral alterations. These results indicate that 1 crotoxin may be an anxiogenic compound, and 2 in contrast to crotoxin, irradiated crotoxin was unable to induce behavioral alterations, which makes it a promising compound for the production of crotalic antiserum

  12. DSC analysis of irradiated proteins from Crotalus durissus terrificus

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Karina Corleto de; Silva, Monica Nascimento da; Goncalves, Karina de Oliveira; Spencer, Patrick Jack; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Full text: Snake bites are a serious public health problem, especially in subtropical countries. In Brazil, the serum, the only effective treatment in case of snake bites, is produced in horses which, despite the large size, have a reduced lifespan due to the high toxicity of the antigen. It is known that ionizing radiation effects - direct and indirect - can modify the molecular structure, affecting the biological properties of proteins. Ionizing radiation has been employed to attenuate the toxicity of snake venoms, aiming to generate an improved antigen with low toxicity. Two proteins, purified from Crotalus durissus terrificus (Cdt) venom were tested in this work: crotoxin and crotamine. Crotoxin, the main toxic compound of Cdt venom, is a heterodimeric protein composed of two subunits: crotapotin and phospholipase A2. Crotamine is a highly basic polypeptide (pI - 10.3), with myotoxic activity and molecular weight of 4882 Da. It is composed of 42 amino acids residues and reticulated by three disulfide bonds. This study aimed to investigate the effects of radiation on crotoxin and crotamine using Differential Scanning Calorimetry (DSC). After isolation of the toxins by chromatographic techniques, they were irradiated with 2.0 kGy from {sup 60}Co source. The thermodynamics analysis, carried out in a METTLER TOLEDO, DSC 822e calorimeter, showed that irradiation promoted changes of the calorimetric profile. These changes suggest that, although radiation induced structural modifications of the protein, denaturation was only partial, since transition states could still be detected, suggesting that some structural elements were still present after irradiation. Taken together, our data suggest that following irradiation, the molecules underwent conformational changes, and that the remaining structural elements displayed a lower enthalpy, clearly indicating that the previously described loss of toxicity of irradiated toxins can be mostly ascribed to structural changes

  13. Stability of vitamin E content of {gamma}-irradiated biscuits

    Energy Technology Data Exchange (ETDEWEB)

    Taipina, Magda S.; Mastro, Nelida L. del [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: nlmastro@ipen.br; magtaipina@ig.com.br; Lamardo, Leda C.A. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Secao de Quimica Biologica]. E-mail: llamardo@ial.sp.gov.br

    2007-07-01

    The technology of food irradiation is seen by the industry as a means of ensuring food safety, since it exposes foods to ionizing radiation that kills insects, moulds and bacteria. The need to eliminate bacterial pathogens from read-to-eat food products must always be balanced with the maintenance of product quality. In addition to determining the effective ionizing radiation doses required for pathogen elimination the effects of irradiation on product chemistry, nutritional value and quality must also been determined. Vitamin E ({alpha}-tocopherol) is one of the most potent natural lipophilic antioxidants commonly present in the human diet. As it is considered a free radical scavenger there is a growing concern that irradiation might reduce the vitamin E content of food products prepared with ingredients rich in any of the dietary source of the vitamin. This work describes the effects of ionizing radiation on the vitamin E content of some biscuits commercially found in the market. Three lots of biscuits were used. Irradiation was performed in a {sup 60}Co Gammacell 220 source, dose rate of about 3.5 kGy/h at doses of 1 kGy and 3 kGy. For vitamin E determination samples were saponified with ethanolic potassium hydroxide in the presence of pyrogallol, and the tocopherols were extracted with petroleum ether. The absorbance was measured at 520 nm. From the obtained results it is possible to conclude that there was a notorious stability of the vitamin content of the biscuits submitted to gamma-irradiation at the assayed doses. (author)

  14. Thermal, tensile and rheological properties of high density polyethylene (HDPE) processed and irradiated by gamma-ray in different atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Ferreto, H. F. R., E-mail: hferreto@ipen.br, E-mail: ana-feitoza@yahoo.com.br; Oliveira, A. C. F., E-mail: hferreto@ipen.br, E-mail: ana-feitoza@yahoo.com.br; Parra, D. F., E-mail: dfparra@ipen.br, E-mail: ablugao@ipen.br; Lugão, A. B., E-mail: dfparra@ipen.br, E-mail: ablugao@ipen.br [Center of Chemistry and Environment, Institute of Energy and Nuclear Research - IPEN (Brazil); Gaia, R., E-mail: renan-gaia7@hotmail.com [Faculdades Oswaldo Cruz (Brazil)

    2014-05-15

    The aim of this paper is to investigate structural changes of high density polyethylene (HDPE) modified by ionizing radiation (gamma rays) in different atmospheres. The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical-chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. This polymer was irradiated with gamma source of {sup 60}Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h. The changes in molecular structure of HDPE, after gamma irradiations were evaluated using thermogravimetric analysis (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere.

  15. Thermal, tensile and rheological properties of high density polyethylene (HDPE) processed and irradiated by gamma-ray in different atmospheres

    Science.gov (United States)

    Ferreto, H. F. R.; Oliveira, A. C. F.; Gaia, R.; Parra, D. F.; Lugão, A. B.

    2014-05-01

    The aim of this paper is to investigate structural changes of high density polyethylene (HDPE) modified by ionizing radiation (gamma rays) in different atmospheres. The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical-chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. This polymer was irradiated with gamma source of 60Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h. The changes in molecular structure of HDPE, after gamma irradiations were evaluated using thermogravimetric analysis (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere.

  16. Improvement of plant parameters of the ROBO gamma irradiation facility due to design modification

    Science.gov (United States)

    Kovacs, A.; Moussa, A.; Othman, I.; Del Valle Odar, C.; Seminario, A.; Linares, M.; Huamanlazo, P.; Aymar, J.; Chu, R.

    1998-06-01

    Two industrial scale, "ROBO" type 60Co gamma irradiation facilities have recently been put into operation in Syria and Peru, and the dosimetry commissioning of both plants have been carried out to determine dose distribution within products and to calculate plant parameters such as efficiency, dose uniformity ratio and throughput. There are some design modifications between the two plants in connection with the location of the carriers with respect to the source plaque and also to each other. The effect of these construction modifications on the plant parameters is discussed in the analysis of the dose distribution data measured in the carriers with depth and height among the four irradiation rows on both sides of the source plaque. The plant parameters were also calculated for different product densities using the technical data of the facilities, and the calculated and measured results were compared to each other.

  17. Biochemical and immunological characterization of the main products of crotoxin irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Dept. de Bioengenharia

    1996-07-01

    Irradiation of crotoxin and its subunits with 2,000 Gy of gamma-rays from {sup 60} Co source leads to aggregation and generation of lower molecular weight breakdown products. Aggregates separated by gel filtration retain at least part of their higher-ordered structure, based on their reactivity with monoclonal antibodies, known to react with conformational epitopes in native crotoxin. Linear epitopes are also preserved, as demonstrated by peptide mapping of the aggregates. These same aggregates can function as antigens to raise antisera which cross-react and neutralize crotoxin. Compared with crotoxin, the aggregates appear to be less myotoxic, largely devoid of phospholipase activity and virtually non-toxic in mice. These results indicate that the irradiation of toxic proteins can promote significant detoxification, but still retain many of the original antigenic and immunological properties of native crotoxin. (author)

  18. Food irradiation makes progress

    Energy Technology Data Exchange (ETDEWEB)

    Kooij, J. van (Joint FAO/IAEA Div. of Isotope and Radiation Applications of Atomic Energy for Food and Agricultural Development, Vienna (Austria))

    1984-06-01

    In the past fifteen years, food irradiation processing policies and programmes have been developed both by a number of individual countries, and through projects supported by FAO, IAEA and WHO. These aim at achieving general acceptance and practical implementation of food irradiation through rigorous investigations of its wholesomeness, technological and economic feasibility, and efforts to achieve the unimpeded movement of irradiated foods in international trade. Food irradiation processing has many uses.

  19. Food irradiation in China

    Energy Technology Data Exchange (ETDEWEB)

    Wedekind, L.

    1986-08-01

    The paper concerns food irradiation in The People's Republic of China. Its use is envisaged to prolong storage times and to improve the quality of specific foodstuffs. Commercialisation in China, demonstration plants, seasonal shortages and losses, Shanghai irradiation centre, health and safety approval, prospects for wider applications and worldwide use of food irradiation, are all discussed.

  20. Impact of total ionizing dose irradiation on Pt/SrBi{sub 2}Ta{sub 2}O{sub 9}/HfTaO/Si memory capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Yan, S. A.; Tang, M. H., E-mail: mhtang@xtu.edu.cn, E-mail: lizheng@xtu.edu.cn; Xiao, Y. G.; Zhang, W. L. [School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105 (China); Hunan Provincial National Defense Key Laboratory of Key Film Materials and Application for Equipments, Xiangtan University, Xiangtan 411105 (China); Hunan Provincial Key Laboratory of Thin Film Materials and Devices, Xiangtan University, Xiangtan 411105 (China); Zhao, W.; Guo, H. X. [Northwest Institute of Nuclear Technology, Xi' an, Shanxi 710024 (China); Xiong, Y. [The School of Mathematics and Computational Science, Xiangtan University, Xiangtan, Hunan 411105 (China); Li, Z., E-mail: mhtang@xtu.edu.cn, E-mail: lizheng@xtu.edu.cn; Ding, H.; Chen, J. W.; Zhou, Y. C. [School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105 (China)

    2015-01-05

    In this work, metal-ferroelectric-insulator-semiconductor (MFIS) structure capacitors with SrBi{sub 2}Ta{sub 2}O{sub 9} (300 nm) as ferroelectric thin film and HfTaO (6 nm, 8 nm, 10 nm, and 12 nm) as insulating buffer layer were proposed and investigated. The prepared capacitors were fabricated and characterized before radiation and then subjected to {sup 60}Co gamma irradiation in steps of two dose levels. Significant irradiation-induced degradation of the electrical characteristics was observed. The radiation experimental results indicated that stability and reliability of as-fabricated MFIS capacitors for nonvolatile memory applications could become uncontrollable under strong irradiation dose and/or long irradiation time.

  1. Preparation and characterization of acrylic acid-grafted poly (vinyl alcohol) hydrogel actuators using γ-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    An, Sung Jun; Lim, Youn Mook; Gwon, Hui Jeong; Kim, Yun Hye; Youn, Min Ho; Nho, Young Chang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Han, Dong Hyun; Kim, Chong Yeal [Dept. of Radiation Science AND Technology, Graduate School of Chonbuk National University, Jeonju (Korea, Republic of)

    2008-01-15

    Active polymer gels expand and contract in response to certain environmental stimuli, such as the application of an electric field or a change in the pH level of the surroundings. This ability to achieve large, reversible deformations with no external mechanical loading has generated much interest in the use of these gels as biomimetic actuators and artificial muscles. In this study, poly (vinyl alcohol)(PVA) grafted acrylic acid monomer (PVA-g-AAc) hydrogels were prepared by {sup 60}Co γ-ray irradiation and their properties such as degree of grafting and weight swelling in electrostimulation as an artificial muscle and actuator were investigated.

  2. Nephropathy in the mature pig after the irradiation of a single kidney: A comparison with the immature pig

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, M.E.; Campling, D.; Rezvani, M.; Golding, S.J.; Hopewell, J.W.

    1989-06-01

    The right kidney of 11 mature 10-month-old Large White female pigs was irradiated with single doses of 9.8-14.0 Gy of 60Co gamma rays. Individual kidney glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured using 99mTc-DTPA and 131I-hippuran renography for periods up to 24 weeks after irradiation. Renal function was assessed either as a functional index, FI (FI = irradiated/unirradiated kidney function), or as the individual kidney GFR and ERPF. The radiation-induced changes after the irradiation of a single kidney (unilaterally irradiated--UI) of mature pigs were compared with those previously observed in 14-week-old immature pigs. Irradiation resulted in a dose-dependent reduction in the FI for both GFR and ERPF. However, these reductions were significantly less than those previously seen in immature pigs. Within 2 weeks of irradiation GFR increased in both the irradiated and the unirradiated kidneys in each animal, compared with unirradiated age-matched control kidneys. No marked changes in renal hemodynamics were seen in mature animals after a single dose of 9.8 Gy. This was in marked contrast to the pronounced reduction in the GFR and ERPF in the irradiated kidney previously observed in immature animals irradiated with an equivalent single dose of X rays. After higher doses, the irradiated kidney in mature pigs showed a dose-dependent reduction in GFR and ERPF. However, the extent of this reduction was significantly less than that seen in immature animals. There was no apparent difference in the response of the unirradiated kidneys in mature or immature pigs. The ED50 values, based on a probit fit to the data for the proportion of functional tests in which the irradiated kidney showed a greater than or equal to 50% reduction in GFR or ERPF, were higher in the mature animals.

  3. Effect of 60 Co-γradiation on some growth and nutrition indexes of Medicago sativa L.%60Co-γ辐射对紫花苜蓿部分生长及营养指标的影响

    Institute of Scientific and Technical Information of China (English)

    刘胜洪; 周玲艳; 杨妙贤; 刘文

    2015-01-01

    将紫花苜蓿( Medicago sativa L.)10个品种种子经2000 Gy剂量的60 Co-γ射线辐射处理,并就辐射处理对其部分生长和营养指标的影响进行了比较分析.结果显示,经60 Co-γ射线处理后,10种紫花苜蓿种子的萌发率、株高和营养指标等都发生了不同程度的变化.辐射处理对先行者、 WL525、 WL903和Adrenalian等紫花苜蓿品种种子萌发率的影响较小,而明显降低了其余大富豪、阿尔冈金、费纳尔、苜蓿王、标杆和WL2321等6个品种的种子萌发率;辐射处理对部分紫花苜蓿品种的生长速度有促进作用,而对部分品种的生长速度有抑制作用;辐射处理对大部分品种的粗蛋白、总糖、总氨基酸浓度有显著增高或降低作用,但对全部品种的干/鲜质量比无显著影响.%Ten Medicago sativa L.varieties were radiated by 2 000 Gy 60 Co-γray, and some growth and nutrition indexes were analyzed.The results showed that the germination rate, plant height and nutritional quality changed at different degrees after the radiation.The germination rates of six varieties, Million-aire, Algonguin, Fnal, Alfaking, Beraga and WL2321, were decreased by the radiation with no effect on those of four varieties, Xianxingzhe, WL525, WL903 and Adrenalian.Growth speed of partial varieties increased and that of partial varieties decreased after the radiation.Crude protein, total sugar and total a-mino acid contents of most varieties increased or decreased significantly but dry/fresh weight ratio of all changed with no significant difference after the radiation.

  4. Effect of gamma irradiation on the properties of plastic bottle sheet

    Science.gov (United States)

    Kumar, Vijay; Ali, Yasir; Sonkawade, R. G.; Dhaliwal, A. S.

    2012-09-01

    In this article, the effects of gamma irradiation on the optical and structural properties of plastic bottle sheets have been studied. Bottle sheets were exposed with 1.25 MeV 60Co γ-ray's source at various dose levels within the range from 0 to 670 kGy. The changes so induced were analyzed by using UV-Vis and X-ray diffraction spectroscopy. UV-Vis spectra show the peaks, their shifting and broadening as a result of gamma irradiation. With increasing γ-dose, the values of the direct and indirect band gap are found to be decreased. These results are in good agreement with the corresponding results published previously for polyethylene terephthalate polymer. We also calculated numbers of carbon atoms per conjugation length. The X-ray diffraction spectra exhibited an increase in peak intensity after gamma irradiation. Furthermore, the percentage crystallinity and crystallite size for pristine and irradiated sample have been calculated. It has been found that both crystallinity and crystallite size increase due to irradiation. In addition, interchain distances, micro strain, inter planar distance, dislocation density and distortion parameters were calculated. The analysis revealed there is the significant decrease in micro strain, dislocation density and distortion parameters with an increase of gamma dose, which is in line with the crystallinity calculation. Moreover, Interchain and Interplanar distances were marginally changed. These results demonstrated the applicability of sheets as a cost-effective dosimeter.

  5. Gamma-ray irradiation tests of CMOS sensors used in imaging techniques

    Directory of Open Access Journals (Sweden)

    Cappello Salvatore G.

    2014-01-01

    Full Text Available Technologically-enhanced electronic image sensors are used in various fields as diagnostic techniques in medicine or space applications. In the latter case the devices can be exposed to intense radiation fluxes over time which may impair the functioning of the same equipment. In this paper we report the results of gamma-ray irradiation tests on CMOS image sensors simulating the space radiation over a long time period. Gamma-ray irradiation tests were carried out by means of IGS-3 gamma irradiation facility of Palermo University, based on 60Co sources with different activities. To reduce the dose rate and realize a narrow gamma-ray beam, a lead-collimation system was purposely built. It permits to have dose rate values less than 10 mGy/s and to irradiate CMOS Image Sensors during operation. The total ionizing dose to CMOS image sensors was monitored in-situ, during irradiation, up to 1000 Gy and images were acquired every 25 Gy. At the end of the tests, the sensors continued to operate despite a background noise and some pixels were completely saturated. These effects, however, involve isolated pixels and therefore, should not affect the image quality.

  6. Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Andre Moreira; Alves, Glaucie J.; Aires, Raquel da Silva; Turibio, Thompson O.; Thomazi, Gabriela O. Coelho