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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 60Co

    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. Toxoplasma gondii vs ionizing radiation: cell and humoral immunity in spleen and gut of isogenic mice immunized with 60Co irradiated tachyzoites

    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-γ-/- mice were immunized with 107 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-γ -/- 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)

  3. 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

    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)

  4. Development of irradiator {sup 60}Co sources

    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)

  5. Development of irradiator 60Co sources

    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 60Co. The development of was based on 11 sources of 60Co 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 60Co is just one cause radionecrosis point (target point) of approximately 5 mm2 with a surrounding and adjacent area of radiodermatitis around about 8 to 10 mm2 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)

  6. Pagure 60Co panoramic irradiation facility

    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)

  7. Decontamination of fermented chicken feet by 60Co irradiation

    Fermented chicken feet was treated by 60Co irradiation, and the aerobic plate count, enumeration of coliforms, pathogens and TBARS value were measured during storage. The results showed that, aerobic plate count of all irradiated samples was lower than control, and enumeration of coliforms, and pathogens of Staphylococcus aureus, Shigella, Salmonella were not detected. TBARS value of all treatments was stable during 60 d storage. It could be concluded that 60Co irradiation of chicken feet was an effective method to prolong its shelf life. (authors)

  8. Effects of 60Co irradiation on virulent Toxoplasma gondii and its use in experimental immunization

    The effects of 60Co irradiation on the virulence and immunogenicity of the RG strain of Toxoplasma gondii was studied by infecting batches of mice with graded inocula of tachyzoites that had been exposed to radiation doses ranging from 0 to 20 000 rad. While doses of 15 000 and 20 000 rads appeared to be effective, and 10 000 rad nearly effective in annulling the virulence, irradiation at 5000 rad was only partially effective in rendering the organisms avirulent and could achieve only a prolongation of survival time of the inoculated mice. The survivors of higher irradiation inocula showed no evidence of the development of the parasite in them, but could resist a limited virulent challenge. The use of a booster inoculation improved both the quality and the duration of protective effect. (author)

  9. 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

    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)

  10. Radiolytic degradation scheme for 60Co-irradiated corticosteroids

    Kane, M.P.; Tsuji, K.

    1983-01-01

    The cobalt 60 radiolytic degradation products have been identified in the following corticosteroids: cortisone, cortisone acetate, hydrocortisone, hydrocortisone acetate, hydrocortisone sodium succinate, isoflupredone acetate, methylprednisolone, methylprednisolone acetate, prednisolone, prednisolone acetate, and prednisone. Two major types of degradation processes have been identified: loss of the corticoid side chain on the D-ring to produce the C-17 ketone and conversion of the C-11 alcohol, if present, to the C-11 ketone. Minor degradation products derived from other changes affecting the side chain are also identified in several corticosteroids. These compounds are frequently associated in corticosteroids as process impurities or degradation compounds. No new radiolytic compounds unique to 60Co-irradiation have been found. The majority of corticosteroids have been shown to be stable to 60Co-irradiation. The rates of radiolytic degradation ranged from 0.2 to 1.4%/Mrad.

  11. Planning a 60Co Irradiation Facility for Fruit Preservation

    A conceptual design for a conveyor system is proposed for use in fruit irradiation. The seasonal nature of the fruit harvest requires that the 60Co source inventory should be sufficient to meet the demand at peak season, but this would be excessive at the beginning and towards the end of the harvest. Because of the short crop period the possibility of other irradiation services should be exploited to ensure full utilization of the facility. For successful extension of fruit shelf-life rigid practices in pre-irradiation treatment are essential and careful packaging is indispensable to the operation of the irradiator. Based on the time required for construction and equipment supply, a period of 18 months should be assumed for completion of the project. (author)

  12. Planning a 60Co irradiation facility for fruit preservation

    A conceptual design for a conveyor system is proposed for use in fruit irradiation. The seasonal nature of the fruit harvest requires that the 60Co source inventory should be sufficient to meet the demand at peak season, but this would be excessive at the beginning and towards the end of the harvest. Because of the short crop period the possibility of other irradiation services should be exploited to ensure full utilization of the facility. For successful extension of fruit shelf-life rigid practices in pre-irradiation treatment are essential and careful packaging is indispensable to the operation of the irradiator. Based on the time required for construction and equipment supply, a period of 18 months should be assumed for completion of the project. (author)

  13. Seed germination of peanuts irradiated with cobalt (60CO)

    This work was realized to evaluate the effect of gamma irradiation (60Co) 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)

  14. Qualities of Patin Fishball Irradiated by Gamma Rays (60Co)

    An experiment on patin fishball quality using gamma irradiation (60Co) has been conducted. Samples were irradiated at 0, 1, 3 and 5 kGy and stored in refrigerator at temperature 10 oC for sixty days. Samples were analysed every fifteen days, except content of fat and protein that analysed only at the beginning and the end of storage. The purpose of this experiment is to know the quality changes of patin fishball irradiated during storage, by measuring of chemical (content of fat, protein, water, TVB value, pH value) and microbiology (TPC aerobic and anaerobic bacteria) changes. The results showed that irradiation did not affect macro nutrient contents (content of fat, protein and water) of patin fishball during storage but irradiation can affect TVB and pH values. Irradiation at 1 kGy can reduce one logarithmic cycle of total aerobic and anaerobic bacteria. The storage life of irradiated patin fishball treated at 1, 3 and 5 kGy could be extended up to 15, 30 and 60 days, respectively. Control samples the storage life could be extended less than 15 days. (author)

  15. 60Co γ-irradiation induced mutation breeding of ginger

    Sprout rhizome and plumelet rhizome of Laiwu ginger were irradiated by 60Co γ-rays at different doses (20, 25, 30 and 35 Gy), and the variations at the VM1, VM2, and VM3 generations were studied. The results showed that the inhibition effect of irradiation on the VM1 generation was found to be increased as the dose increased, and the sprout rhizome was more sensitive to γ-irradiation than the plumelet rhizome. The LD50 and LD60 dose of plumelet rhizomes were 20 and 25 Gy, respectively, and the optimum irradiation dose was 25Gy. The LD50 and LD60 dose of sprout rhizomes were below 20 Gy. Seven types of mutants were found and selected in VM2 generation. The induced mutation characters were unstable in the VM3 generation. Three mutant lines (GDC2531, PZC3026, ZLX2007) selected from VM3 generation showed high yield, and fresh weight of rhizomes increased 33.5%, 27.5% and 24.9%, respectively compared to control. (authors)

  16. Response of adrenal gland to whole body 60Co irradiation

    Whole body of the adult albino rates was exposed to 60Co radiation in a single dose of 600 R. Following irradiation the adrenal serotonin level was found higher till the end of 8th week except a fall on 14th day, whereas the blood 5HT level remained lower than the normal except a slight rise at the end of 1st week and dropped down at 14 days followed by a further rise. The blood catecholamine level was found increased at the end of 14th day followed by a fall at 4th and 8th weeks, but the levels were moving round the normal value. The histological studies of adrenal gland showed degranulation and hypertrophy of adrenal cortex and medullary cells at various intervals of post-irradiation. On the whole it is observed that maximum changes in the level of biogenic amines take place within 14 days after irradiation, and maximum rate of mortality also coincide with this period. Thus bringing out the fact that adrenal bioamines play an important role in the vital activities of the animals. (author)

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

    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)

  18. Effect of 60Co-gamma whole-body irradiation on serum amylase level

    Changes of serum amylase activity in rats, after several doses of acut 60Co-gamma irradiation as a function of time were investigated. These changes proved to be of no diagnostic value in early radiation damage. (author)

  19. Manufacture of 60Co source irradiation facility and measurement of radiation filed

    60Co source radiation facility is an important equipment to produce reference radiation filed, according to national standard, the scattered dose rate must be less than 5% of the total dose rate in the reference radiation filed. Scattered radiation contribution and uniformity of reference radiation field are important parameters to describe the radiation performance of 60CO source irradiation device, Monte Carlo method was used to study the scattered radiation and uniformity of the reference radiation filed to provide theoretical basis for the design of 60CO source irradiating device in order to avoid economic losses caused by design mistakes. When 60CO source irradiating device was manufactured, PTW ionization chamber was used to measure the irradiation field. The results showed that the scattered radiation and uniformity of the radiation filed were in good agreement with the simulation results. The radiation performance met the design requirements. (authors)

  20. Detection of Argentine onions treated with 60 Co irradiation

    Brazil has been the most important MERCOSUL's purchaser of fresh onions from Argentina. The increased claim for this fresh product has forced a consensus between the members nations, as regards to phytosanitary restrictions. The radio inhibition is described on National Food Codes in Brazil and Argentina. Methods of food irradiation detection must be performed, since they increase the consumer confidence. Quick and simple screening tests indicate whether a food product has been irradiated or not. This present study verified the DNA fragments of argentine fresh onions, produced during radiation process and 6 months of storage period. The DNA fragments are analyzed for detection of irradiated foods. The irradiated onions presented extensive DNA migrations, as comets, when submitted to agarose gel electrophoresis. They also showed more shelf life compared to the unirradiated onions. The unirradiated samples exhibited only limited DNA migration. This initial screen method showed to be effective for detection of irradiated onions. (author)

  1. Histological variations in liver of freshwater fish Oreochromis mossambicus exposed to 60Co gamma irradiation

    The irradiation effect of 60Co at the three dose level of 3 mGy, 30 mGy and 300 mGy on the histology of liver of the freshwater fish Oreochromis mossambicus was investigated. The liver of O. mossambicus was dissected out and processed for light microscopy studies. 60Co exposed O. mossambicus were found to result in several alterations in the histoarchitecture of liver. The alterations included mild congestion of blood vessels, structural alteration, cellular swelling, vacuolation and necrotic liver cells, indicating a definite response to 60Co irradiation. The results suggest that the liver of O. mossambicus exposed to 60Co were structurally altered with increasing dose levels. It is to record that alteration in the liver does not affect the physiology, behaviour or lethality of the individuals. Self regulating mechanisms would have influenced the liver to remain sustained. To confirm the same further studies in the direction by increasing dose level is required. - Highlights: ► Fish Oreochromis mossambicus irradiated to the dose of 3 mGy, 30 mGy and 300 mGy. ► Histoarchitecture of liver altered with increasing dose levels of 60Co. ► Alteration in the liver does not affect the physiology, behaviour or lethality. ► Self regulating mechanisms might have prevented from Lethality. ► HSI index value for exposed group reported (60Co.

  2. Molecular exclusion chromatographic analysis on 60Co irradiated rattlesnake

    Ionizing radiations are sufficiently energetic to be able of breaking chemical bonds and as result of that molecules of substances present in the irradiated will be chemically changed and their biological properties affected also. In this paper the effects of gamma radiation of Co-60 on the rattlesnake venom were studied. A pool of positive crotamina Crotalus durissus terrificus venom was dissolved in 0,15 M NaCl and irradiated with Co-60. Doses of 100, 250, 500, 750, 1500 and 2000 Gy were applied at the dose rate of 1190 Gy/h. With doses over 500 Gy the solutions became turbid, suggesting the presence of aggregates and structural changes of the proteins. The concentration of proteins from the filtered solution was measured by the Lowry method. One ml samples were measured at 230 nm. The partition coefficients and the areas of the three main fraction obtained were calculated. (author)

  3. Effect of 60Co γ-ray irradiation on salmonella in high immunity egg yolk

    Salmonella were inoculated into the yolk and irradiated with different dose of 60Co γ-ray. The results show that 3 kGy irradiation dose can kill all Salmonella in the yolk and D10 value of Salmonella in the yolk is 0.36-0.46 kGy

  4. Effect of 60Co γ irradiation and GA3 treatment on mutation of Carica papaya L

    The seeds of Carica papaya L. were irradiated by 60Co γ-rays of 10-40 Gy and treated by GA3 of 10-50 mg/L after irradiation. The results showed that small nuclear cell percentage, chromosome variation percentage and leaf variability of papaya seedling increased with increase of irradiation dose, the pollen fertility and fruit quality decreased. GA3 of 10-50 mg/L treatment after irradiation could alleviate the irradiation harm, and the effect of lower concentration of GA3 was better than higher concentration with lower dose irradiation, however, the effect of higher concentration of GA3 was better with higher dose irradiation

  5. Changes of collagen metabolism induced by 60Co γ-ray external irradiation

    Objective: To study the changes and molecular mechanism of collagen metabolism induced by 60Co γ-ray external irradiation of local tissues. Methods: After the hip skin of rabbits was irradiated with 60Co γ-rays, the changes of collagen metabolism and collagen contents of the rabbits' skin of different sex groups were determined. Results: The γ-rays decreased the soluble collagen contents (especially type III) and increased the activity of MMPs in local tissues. Although the radiation affected the contents of serum SOD, 5-HT, and LPO, its influence on the contents in local tissues was not remarkable. There were changes of collagen metabolism in local tissues after radiation injury, but no differences were found in SOD, 5-HT, LPO, and glucosamine of tissues. Conclusion: The main mechanism of skin burn induced by 60Co γ-rays may be that the changes of collagen metabolism bring about the pathological effect

  6. A description of 60Co gamma irradiation facilities in the Radiation Biology and Health Physics branch

    The Radiation Biology and Health Physics Branch manages three 60Co irradiation facilities, to (Gammabeam 150C, Gammacell 200 and Gammacell 220) provide a range of dose rates suitable for variety of applications. This report describes the physical characteristics of the facilities, a description of the dosimetry and operating procedures. (author). 6 refs., tabs., figs

  7. Analysis of the microbial growth in {sup 60}Co {gamma}-irradiated foods by calorimetry

    Furuta, Masakazu; Hayashi, Toshio [Osaka Pref. Univ., Research Institute for Advanced Science Technology, Sakai, Osaka (Japan); Hamasaki, Koji; Wirkner, Sandra; Constantinoiu, Elena; Takahashi, Katsutada [Osaka Pref. Univ., College of Agriculture, Sakai, Osaka (Japan)

    2002-09-01

    Using a heat conduction calorimeter equipped with 24 sample units the heat evolutions from growing {sup 60}Co {gamma}-irradiated bioburden of black pepper seeds and frozen beef were detected in the form of growth thermograms. {sup 60}Co {gamma}-irradiation affected the growth pattern in which a dose-dependent reduction of the growth rate constant was observed together with the retardation in growth, indicating a combination of bactericidal and bacteriostatic effects. We successfully determined the minimal inactivation doses for the two food samples using the relationship between the irradiation dose and the retardation in growth t{sub {alpha}}, or the growth rate constant {mu} obtained from the growth thermograms. These results strongly suggested the possibility of calorimetry as measure of predictive microbiology in food irradiation. (author)

  8. Effect of 60Co-γ ray irradiation on green coffee beans, 1

    Green coffee beans were irradiated with 60Co-γ rays at doses of 0, 0.05, 0.5, 5.0 and 10.0 Mrad and the changes of general components in green and roast coffee beans were investigated together with those of the organoleptic properties of roast beans during storage according to the cup testing. In case of Brazil santos beans, irradiation of some 0.05 Mrad 60Co-γ ray gave rather favourable mild flavour and no harmful influence on the quality of coffee, and moreover, would tend to extend the shelf life of roast beans. But influence of irradiation on the quality of coffee differed somewhat between two cultivars, Brazil santos and Colombia. (auth.)

  9. SV40 DNA amplification and reintegration in surviving hamster cells after 60Co γ-irradiation

    SV40-transformed Chinese hamster embryo cells were exposed to 60Co γ-irradiation and the fate of the integrated SV40 sequences was pursued over a period of 20 days following radiation exposure. As shown by colony hybridization, integrated SV40 sequences were amplified in surviving and non-surviving cells. At later times, however, clonal sublines of surviving cells grown for 20-30 cell generations after irradiation had lost most of their amplified SV40 copies but showed altered restriction fragment patterns indicating reintegration of SV40 sequences at new sites of the hamster genome. This suggest that 60Co γ-irradiation can generate mutations by inducing over-replication of chromosome segments that are then substrates of enzymatic rearrangements. (author)

  10. Effect of Vaccination with Irradiated Tachyzoites on Histopathological Changes and DNA Damage in Hepatocytes of Experimental Toxoplasmosis

    Current strategies for the control of toxoplasmosis are based on chemotherapy, however successful vaccine has also been demonstrated. The present study aims to assess the effect of the vaccination with radiation-attenuated tachyzoites in challenged mice regarding histopathological alteration and DNA damage of hepatocytes. Sixty mice were equally divided as follow: Group I left as a normal control group II was infected with 2x103 RH virulent tachyzoite s (infected control). Groups III and IV were subdivided into two subgroups a and b where subgroups IIIa and IVa were vaccinate d with 2.47 mw-min/cm2 UV and 0.3 KGy gamma radiation – attenuate d tachyzoites respectively without challenge (as vaccine control). Subgroups III b and IV b were vaccinate d with UV and gamma radiation - attenuated tachyzoites and challenged after three weeks with 2x103 RH virulent tachyzoites. Livers were examined for histopathological changes and DNA comet assay. It was observed that acute infection with Toxoplasma tachyzoites produced toxic effects which lead to severe damage in liver tissues and DNA of hepatocytes. Meanwhile, the protective effect of UV or gamma radiation-attenuated tachyzoites vaccine resulted in the maintenance of normal histopathological characteristics and DNA of hepatocyte s and UV irradiation is better in its protective capacity

  11. The studies on apple preservation by 60Coirradiation

    Studies on 60Coirradiation of Golden Delicious apple have been carried out. The results showed that the optimum irradiation dosage for stored apple was ranged from 0.3-0.5 kGy. With this dosage, the contents of vitamin C and titratable acidity in these apples had no significant change compared with unirradiated apples. The respiratory rate and the amount of ethylene release were decreased after irradiation. The mortality of the verticillate pathogenic fungi was 97% at the dose of 0.5 kGy

  12. Experiments for inactivation of mycoplasms and bacteria in calf sera, using 60Co irradiation

    The use of 60Co gamma radiation to inactivate mycoplasms in calf serum, newborn calf serum, and fetal calf serum is reported. A dose of 3 kGy, independent of dose rate, was found to be sufficient for inactivation in the above sera of several mycoplasms, including Acholeplasma laidlawii, Mycoplasma orale, M. arginini, M. hyorhinis, and M. bovis. The critical dose proved to be at 2 kGy. No difference was found to exist between the above species in susceptibility to irradiation in diluted sera (50% and 10% in Eagle MEM). Sensibility of wild mycoplasm strains was found to be identical with that of laboratory strains. Hence, 60Co gamma irradiation of sera appears to be a safe method by which to make sera free of mycoplasms. Bacillus subtilis in calf serum was inactivated by doses above 18 kGy, with the critical dose being 15 kGy. (author)

  13. Effects of 60Co-γ ray irradiation on antioxidant enzyme activities in tobacco

    Effects of 300Gy 60Co-γ ray irradiation on the activities of 3 antioxidant enzymes in tobacco were studied in this paper. The results showed that the activities of superoxide dismutase (SOD), peroxidas (POD) and catalse (CAT) in tobacco were gradually increased. All the activities of SOD POD and CAT reached the maximums at 12 h and then gradually decreased. Similar results were also observed in the expression of sod, pod and cat genes. These results indicated that the activities of antioxidant enzymes could play an important role in tobacco tolerance against irradiation

  14. Effect of 60Co-irradiation on penicillin G procaine in veterinary mastitis products

    The effect of 60Co-irradation on penicillin G procaine in a peanut oil-based veterinary mastitis product was examined by reversed-phase high-performance liquid chromatography (HPLC). The HPLC method is capable of separating and quantifiying procaine, penicillin G, and various degradation compounds. Values obtained by the HPLC method on the product irradiated and stored at various temperatures correlated well with those of the microbiological assay. No significant decrease in the procaine was detected even after 4.0-Mrad irradiation. The HPLC method is applicable for analysis of other beta-lactam antibiotics

  15. Biological effects of 60Co γ-irradiation on Laiwu ginger VM1 growth

    Rhizome of Laiwu ginger were treated with γ-irradiation at the doses of 0, 20, 40 and 60 Gy. The results showed that 60Co γ-irradiation inhibited the rhizome burgeoning, and decreased the survival rate of the seedlings, rate of leaf- expansion and the growth of plants (VM1). The inhibition effects became stronger with the increase of the irradiation dose. Different bands were found through the analysis of POD, EST isozymes and RAPD of VM1 plants, which showed that variation on molecular level occurred in VM1 plants. LD30-40 was appropriate for the irradiation of rhizomes of Laiwu ginger and the optimal irradiation dose was about 20- 30 Gy. (authors)

  16. Effect of dosage on property and structure of gelatin irradiated by 60Co γ-ray

    The gelatin was irradiated for 0-60 kGy dosages by 60Co γ-ray. The relationship of dosage and properties including viscosity, gel strength, mechanical property, molecular weight and protein component was discussed. The results show that there is a negative correlation between the dosage and intrinsic viscosity, relative viscosity, gel strength and molecular weight. With the increase of irradiation dosage, the γ, β, α chain content of gelatin decreases but the small molecules content increases, and relative molecular weight distribution changes wider. The elongation decreases but tensile strength of gelatin film increases. Compared with no irradiation one, the irradiation gelatin has more compact and smooth surface texture. It is assumed that when the limited water and oxygen exist during the irradiation process, cross-linking and degradation of gelatin molecular produce simultaneously and the main reaction is cross-linking. The reaction degree increases with the dosage. (authors)

  17. Decontamination of salmonella from the coastal fish meals by 60Co γ ray irradiation

    The decontamination fo salmonellae from fish meal samples by irradiation which 60Co γ ray was examined. Sixteen strains of Salmonella were used. A composite fish meal sample was prepared by mixing with different coastal meals, and after radiation sterilization at a dose of 20 kGy 60Co γ ray, which was employed as the salmonella-free meal sample. D10 values of test strains determined in buffered saline were found to range from 0.08 to 0.36 kGy, and inactivation factors at a dose of 1 kGy ranged from 102.8 to 1013. D10 values of test strains determined in the salmonella-free meal sample ranged from 0.59 to 1.64 kGy, and the inactivation factors at a dose of 10 kGy were found to range from 106.1 to 1017. Interestingly the D10 values of salmonellae determined in fish meal samples were 10 times as much compared with those determined in buffered saline. From the commercial aspects of coastal fish meal production, destruction of salmonellae in fish meals by 60Co γ ray irradiation was found to be much more practical than other methods such as dry heating and ethylene oxide fumigation. (author)

  18. Effects of 60Co γ-rays irradiation on seed growth of ground-cover chrysanthemum

    The seeds of ground-cover chrysanthemum were used to study the effects of different doses of 60Co γ-rays irradiation(10-50 Gy) on seed germination and physiological characteristics. The results showed that the rate of seed germination and seedling survival decreased significantly with the irradiation doses. With the increase of irradiation dose to above 20 Gy, the content of malondialdehyde (MDA) and activity of peroxidase (POD) in seedlings significantly increased. The similar trends were found in the activities of superoxide dismutase (SOD) and glutathione reductase (GR). Catalase (CAT) activity increased at doses lower than 20 Gy, and then decreased at the higher doses, whereas ascorbate peroxidase (APX) activity did not alter except for 40 Gy. It is concluded that the suitable irradiation dose of mutation breeding is 20 Gy for the seeds of ground-cover chrysanthemum. Although 60Co γ-rays irradiation resulted in damage of membrane lipid peroxidation in the survival seedlings, the increased activity of CAT and POD could protect them against the damage. (authors)

  19. Effects of testicular irradiation with 60Co in guinea pigs CAVIA PORCELLUS

    Improvements were made in restaint systems and in the technique of electroejaculation in guinea pigs, emphasizing safety, effectiveness and repetition. Arrangements for simultaneous testicular irradiation with 60Co in 5 animals and a phantom to test dose levels in the target region and scattering were also made. Effects of single and fractionated exposures on sperm were studied. A collimated point-shaped 60Co-machine calibrated to 7 R/min was used as radiation source. Groups of five 12 month aged male guinea pigs were exposed to either single testicular irradiation of 50, 100, 200 and 400 R or fractionated weekly testicular irradiation of 2, 5, 10 and 20 R, during 10 weeks. A last group was exposed to 4 fractionated testicular irradiations of 20 R at time intervals of 21 days and a group of 8 animals was used as control. Semen samples evaluations were made during 5 weeks before irradiation and in the subsequent 11 weeks. Abnormalities in sperm morphology were studied by William's method and phase contrast microscopy. Mean percentages of semen normal espermatzoons and spermatic abnormalities are shown in figures and photomicrographs. Marked differences on concentration, sperm motility and sperm abnormalities were found, but not on volume, in favour of 100 and 200 R single doses levels, as compared to fractionated 10 and 20 R. (Author)

  20. Protective effect of gingerol on leucocyte and bone marrow DNA of 60Co γ-rays irradiated mice

    In this article, the effect of gingerol on peripheral leucocyte and bone marrow DNA of 60Co γ-rays irradiated mice was developed., Twenty-four healthy healthy female Kunming mice were randomly divided into 4 groups: control, gingerol, irradiation and gingerol + irradiation group. Gingerol group and gingerol + irradiation group were given gingerol intragastrically once a day for five days. Irradiation group and gingerol + irradiation group were suffered from 5 Gy 60Co γ-rays irradiation at the rate of 1.2 Gy/min on the 6th day. Blood samples, spleens, livers and thigh bones were collected to be measured after 48 h. The results showed that, compared with irradiation group, gingerol + irradiation group had significantly higher spleen index (p60Co γ-rays irradiated mice. (authors)

  1. The study of mildew proof effect of 60Co γ irradiation on leather shoes

    Leather products occupy an important place in the national economy. In order to prevent from mildewing of leather products in storage, transportation and sale, the packed shoes were irradiated with 60Co γ ray. Test materials are cattle, sheep and pig leather shoes. The results shows that: 1. There are 11 types of molds which make leather shoes mildewed: Oospora sp, Rhizopus oryzae Went and Grrelings, Aspergillus flavus Link, Aspergillus terreus thom, Monilia sp, Botrytis sp, Aspergillus niger V. Tiegh, Penicillum Lividum Westling, Penicillum Corylophilum Dieckx, Penicillum Cyaneum (B. and S.) Biourge and Penicillum Verrulosum Peeyrone. 2. The three types of shoes packed with polyethylene film can be prevented from mildewing after irradiation at level of 12 kGy. 3. The irradiation at 30 kGy does not change the physical properties of the shoes. 4. The irradiated shoes packed with polyethylene film can prevent mildewing, but unpacked ones would be mildewed again

  2. Distribution of 60Co and 54Mn in graphite material of irradiated HTGR fuel assemblies

    Distribution of 60Co and 54Mn was measured in the graphite sleeves and blocks of the third and fourth HTGR fuel assemblies irradiated in the Oarai Gas Loop-1 (OGL-1), which is a high temperature inpile gas loop installed in the Japan Materials Testing Reactor (JMTR) of Japan Atomic Energy Research Institute (JAERI). Axial and circumferential profiles were obtained by gamma spectrometry, and radial profiles by lathe sectioning with gamma spectrometry. Distribution of 60Co is in good agreement with that of thermal neutron flux, and the Co content in the graphite is estimated to be -- 1 x 10-9 in weight fraction. Concentration of 54Mn decreases toward the axial center in its axial profile, and radially is almost uniform inside and appreciably higher at free surfaces. An estimated Fe content of --10-8 in wight fraction is smaller by two orders of magnitude than that from chemical analysis. Higher concentraion of 60Co and 54Mn at the free surfaces suggests the importance of transportation process of these nuclides in the coolant loop. (author)

  3. Phenotype and molecular analysis of M1 generation of stylosanthes irradiated by 60Co

    The seeds of Stylosanthes guianensis SW. ‘Reyan No.13’ were irradiated by 60Co at 0, 325, 487 and 974 Gy. Phenotype and molecular variations of Stylosanthes M1 generations were studied. Germination percentage, plant height, leaf length and stem diameter of M1 seedlings were determined using SRAP-PCR. Results showed that biological character indices of treatments were significantly lower than that of control (CK). Irradiation inhibited plant growth. Growth indices of 974 Gy treatment, except leaf length, were significantly lower than CK and other two treatments. Eight effective primers selected from 24 primers combination were used for SRAP-PCR. SRAP analysis revealed that the 57 of 88 DNA fragments were amplified showing polymorphisms. The average percentage of polymorphic bands was 64.77%. The effects of 60Coγ irradiation on DNA variation of seedlings were varied from different treatments. Numbers of polymorphic bands changed after irradiation. Coefficient of variation was in direct proportion to irradiation doses. Variation rates of 325 Gy, 487 Gy and 974 Gy treatments were 22.0%, 38.1% and 41.5%, respectively. The Nei’s genetic similarity coefficient of all treatments was ranged from 0.585 to 0.780 by software NTSYSpc 2.1 based on SRAP results and the average Nei's coefficient was 0.678. The Nei’s genetic similarity coefficient of 974 Gy treatment was 0.585 and variation degree was highest among all treatments, 487 Gy treatment was second and 325 Gy treatment was the lowest one. Based on present bands, four irradiated treatments were classified into two major groups by UPGMA cluster analysis. Group 1 included CK, 325 Gy and 487 Gy treatment and group 2 included 974 Gy. SRAP analysis determined variation of Stylosanthes after irradiation and the results of SRAP analysis were consistent with their biological indexes in some extent

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

    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.

  5. The influence of 60Co gamma irradiation for downy mildew infection on corn

    Corn seeds of Genjah kertas variety were irradiated with 60Co gamma in the range of 0 rad - 40.000 rads, at interval of 2000 rads, as preliminary investigation to obtain possibilities of corn mutation. Several agronomical effects of radiation on the seedling-plant such as seed germination, height of the seedling, ages of flowering, ages of harvesting, length and circle of the cob, 100U dry seeds weight, number and diameter of stomata, and percentage of downy mildew infection have been observed. The exact conclusion can be obtained only after testing the results of M2 and M3. (author)

  6. Humoral immune response against native or 60Co irradiated venom and mucus from stingray Paratrygon aiereba

    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 60Co 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 60Co 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)

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

    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

    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 0.5 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)

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

    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. - Highlights: • Poly-HEMA was grafted onto the surface of SS by 60Co-γ-ray irradiation. • Pristine SS was coated by dopamine to form a dense poly-dopamine film before radiation grafting. • The biocompatibility and hydrophility of SS were improved after the grafting of HEMA

  10. Cell survival of human tumor cells compared with normal fibroblasts following 60Co gamma irradiation

    Three tumor cell lines, two of which were shown to be HeLa cells, were irradiated with 60Co gamma irradiation, together with two cell cultures of normal human diploid fibroblasts. Cell survival was studied in three different experiments over a dose range of 2 to 14 gray. All the tumor cell lines showed a very wide shoulder in the dose response curves in contrast to the extremely narrow shoulder of the normal fibroblasts. In addition, the D/sub o/ values for the tumor cell lines were somewhat greater. These two characteristics of the dose response curves resulted in up to 2 orders of magnitude less sensitivity for cell inactivation of HeLa cells when compared with normal cells at high doses (10 gray). Because of these large differences, the extrapolation of results from the irradiation of HeLa cells concerning the mechanisms of normal cell killing should be interpreted with great caution

  11. Effect of 60Co γ-irradiation on the infectivity of toxoplasma gondii bradyzoites

    Homogenates of mouse brains harboring toxoplasma NT strain cysts were irradiated at various doses of 60Co γ ray and digested with 0.4% trypsin buffer to release bradyzoites from cysts. The suspensions containing various number bradyzoites were obtained through a serial 10-fold dilution in saline solution and inoculated intraperitoneally into mice separately. Infectivity of toxoplasma bradyzoites was determined by bioassay of mice. A group of mice inoculated with non-irradiated bradyzoites was used as control. Results showed that the minimal effective dose of γ rays controlling infectivity of toxoplasma NT strain bradyzoites was 0.55 kGy. Effect of 0.1 kGy γ rays on infectivity of toxoplasma bradyzoites was not significant. Infectivity of bradyzoites irradiated at 0.45 kGy had 104 fold reduction in comparison with that of 0.1 kGy

  12. Effects of 60Co irradiation on the genetics of indian meal moth

    4 ∼ 5 days old male pupae of Indian meal moth, Plodia interpunctella Hubner were irradiated with 1, 3, 5, 7 and 10 krad of 60Co γ-ray. The male moths developed from treated pupae and their F1 generation were put together with normal female moths for copulation separately. The genetic effects of irradiation was studied and the results showed that the effects of irradiation were significant, which related to the irradiation dosage, on both parental and filial generations. Only 40% of the pupae was emerged, when they were irradiated at 10 krad. The effects on deformation rates, survival rates, copulation abilities, fecundities, hatching rates and genetic sterilities varied with different irradiation dosage treatment. With consideration of the total irradiation effect, the dosage lower than 5 krad is desirable for inducing the sterility of adults and sex chain recessive lethal gene. With 1, 5 and 7 krad of irradiation, a mutant of P. interpunctella with transparent wings was induced, which provides a marking feature in control of Indian meal moth by sex chain recessive lethal gene

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

    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)

  14. Study for optimization of a 60 Co industrial irradiator of 250 k Ci

    This work presents results of a benchmark between calculated and experimental absorbed dose values for a typical product, in a 60 Co industrial irradiator, located at ININ, Mexico. The goal of this work is to reach a ± 10 % approximation between both values. ININ 60 Co industrial irradiator is a two level, two layer system with overlapping product configuration, 56 irradiation positions with an activity of around 250 k Ci. Calculated values were obtained by QAD-CGGP code. This code uses a point kernel technique, build-up factors fitting was done by geometrical progression and combinatorial geometry was used for 3 D system description. Main code modifications were related with source simulation by punctual sources and energy spectrum (16 energy groups) and anisotropic emission were also considered. Experimental data were obtained from routine dosimetry which was done with red acrylic pellets; they were irradiated together the product in predetermined positions, for 36 maximum and minimum absorbed dose values. Typical product was polypropylene Petri dish packages, apparent density 0.13 g/cm3. It was chosen because regular geometry (2 packages per full irradiator container) and enough amount for considering homogeneous loading inside irradiation chamber. Required minimum dose was 15 kGy. Results showed a 8% variation between calculated and experimental values for maximum absorbed dose (18.2 kGy vs 16.8 kGy) and 3 % variation for minimum absorbed dose (13.8 kGy vs 14.3 kGy); these results fixed with the original proposal. (Author)

  15. 60Co irradiation for sterilization of veterinary mastitis products containing antibiotics and steroids

    Tsuji, K.; Kane, M. P.; Rahn, P. D.; Steindler, K. A.

    Effects of 60Co irradiation for sterilization of veterinary mastitis products were evaluated. The mastitis products which were examined contained various combinations of antibiotics and steroids suspended in peanut oil vehicle. Bioburden data indicated that the unirradiated products were only occasionally contaminated with microorganisms. The D-values of the nonsterile product and environmental isolates were 0.028, 0.15, 0.017, and 0.018 Mrads for Aspergillus fumigatus, Penicillium oxalicum, Pseudomonas aeruginosa, and Pseudomonas maltophilia, respectively. The D-value of the biological indicator organism, Bacillus pumilus spores, in the vehicle was 0.27 Mrads. Thus, an irradiation dose of 1.6 Mrads would be sufficient to achieve six log cycles of destruction of the biological indicator organism. The minimum absorbed irradiation dose of 2.5 Mrads preferred by many countries for sterilization would achieve 9.3 log cycle destruction of the indicator organism and guarantee a probability of 1 × 10 -15 assurance for the most radio-resistant product isolate, Penicillium oxalicum. In order to examine short and long term chemical stabilities of active components, stability indicating high-performance liquid chromatographic (HPLC) methods for the determination of the following antibiotics and steroids were developed. They were: dihydrostreptomycin, neomycin, novobiocin, penicillin G, hydrocortisone acetate, hydrocortisone sodium succinate, and prednisolone. The rates of degradation and radiolytic degradation schemes for the majority of these compounds were elucidated. Formation of new compounds was not observed in these antibiotics and steroids upon 60Co irradiation. The compounds that increased by irradiation were inherently present in commercially available non-irradiated lots and/or can easily be formed by either acidic, basic, or thermal treatment.

  16. 60CoIrradiation Affects the Enzymatic Antioxidant System of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae)

    Ke Zhang; Zhibin Li; Shaowen Zhu; Qunfang Weng

    2014-01-01

    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), p...

  17. Studies on mutagenic activity of 60Co γ-ray irradiated rape pollen

    In the present study on disinfection, the rape pollen was irradiated with 2.5 kGy 60Co γ-ray. Micronuclei, sister chromatid exchanges (SCE) of bone marrow cells and chromosomal aberrations of meiotic cells in mice were used as an indicater of chromosomal damage to study the mutagenicity of irradiated rape pollen. The results are as follows: (1) The frequency of micronuclei in polychromatic erythrocytes is 2.00 per mille; nucleated cells is 0.8 per mille in control group. In the numbers of polychromatic erythrocytes and nucleated cells with micronuclei, there is no obviously difference in irradiated and unirradiated groups. (2) SCE incidence of control group is 2.01 ± 0.12/cell. No significant difference in the frequency of SCE exists between non-irradiated rape pollen and the control groups. But the frequency of SCE in irradiated rape pollen group (3000 mg/kg/day x 7) is 2.36 ± 0.12/cell; high dose group (6000 mg/kg/day x 7) is 2.96 ± 0.14/cell. In comparison with control group, there is a significant difference. (3) The chromatid breaks, fragments, and univalents in primary spermatocytes have been obseved. The frequencies of chromosomal aberration showed no obviously difference among irradiated and non-irradiated rape pollen groups

  18. A case of radiation gastroduodenitis caused by 60Co-irradiation therapy for hepatoma

    A 56-year-old man with hepatoma, who had been treated with total 3,960 rad of 60Co-irradiation 2 months previously, was readmitted to the hospital because of fever and anemia. Following admission, he passed tarry stools every day. Barium meal examination revealed esophageal varices and erosive gastritis of the antrum. At endoscopy, many hemorrhagic erosions were found in the gastric antrum and the first part of duodenum, which were located in the irradiation area. Since repeated blood transfusion failed to improve anemia, a complete fasting with intravenous hyperalimentation and antacid therapy were started. Two months later, feeding was started and thereafter continued without any appreciable GI bleeding or worsening of anemia. Endoscopic examination at this time revealed only a few erosions scattered over the edematous antral mucosa as well as the proximal duodenum. IVH, antacids and abstinence from food seem to be an effective measure in the treatment of radiation injury of the gut. (author)

  19. The degradation of p-chloronitrobenzene in aqueous solution by 60Coirradiation

    The degradation of p-Chloronitrobenzene (p-CNB) in aqueous solution was investigated by 60Coirradiation. The concentrations of p-CNB and inorganic ions generated during the irradiation process were measured by HPLC and Ion Chromatography technology. And also, the factors affecting degradation degree, such as absorbed dose, radiation aura, were studied in detail. It was found that the degradation degree of p-CNB and the concentrations of ions increased with absorbed dose. The presence of O2 was more favorable to the degradation of p-CNB. Furthermore, the experimental results showed that both hydrated electron and hydroxyl radical generated from water radiolysis could degrade p- CNB effectively and produce Cl-, NO3-, NH4- in the solutions. (authors)

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

    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.

  1. Biochemical and immunological alterations of 60 Co irradiated Bothrops jararacussu venom

    Proteins irradiation leads to structural alterations resulting in activity and function loss. This process has been useful to detoxify animal venoms and toxins, resulting in low toxicity products which increased immunogenicity. The Bothrops jararacussu venom behaves as a weak immunogen and its lethal activity in not neutralized by either autologous, heterologous or bothropic polyvalent antisera. This venom is markedly myotoxic and and the commercial bothropic antiserum does not neutralize this activity, because of this low immunogenicity of the myotoxins. This present work was done in order to evaluate the possibility of irradiating Bothrops jararacussu, intending to increase the immunogenicity of the myotoxic components, leading to productions of myotoxins neutralizing antibodies. Bothrops jararacussu venom samples were irradiated with 500, 1000 and 2000 Gy of 60 Co gamma rays. A 2.3 folds decrease of toxicity was observed for the 1000 Gy irradiated samples while the 2000 Gy irradiated sample was at least 3.7 folds attenuated. On the other hand, the 500 Gy did not promote any detoxification. Electrophoresis and HPLC data indicate that the irradiation lead to the formation of high molecular weight products (aggregates). The proteolytic and phospholipasic activities decreased in a dose dependent manner, the phospholipases being more resistant than the proteases. Both the animals (rabbit) immunized with either native or 2000 Gy irradiated venom produced native venom binding antibodies, a slightly higher titer being obtained in the serum of the rabbit immunized with the irradiated samples. Western blot data indicate that the anti-irradiated venom Ig Gs recognised a greater amount of either autologous or heterologous venom bands, both sera behaving as genus specific. The anti-native serum did not neutralize the myotoxic activity of native venom, while the anti-irradiated one was able to neutralize this activity. (author)

  2. A study on the irradiation effect of 60Co gamma ray on dental polymethylmethacrylate bonded parts

    In this paper we describe an experimental study on the irradiation effect of 60Co gamma ray on dental polymethylmethacrylate (P.M.M.A.) welding part, hot and cold polymerizing adhesion part. It was found that from the result of tension test, no remarkable change of mechanical property is found with any of the bonded parts by the irradiation dose up to 107 r., and no deterioration by irradiation is observed. And then, according to the results of bending test, it is found that, although the three different bonded parts have different features, the strength of the welded part and of the part adhered by hot polymerizing adhesive becomes lower by irradiation, and bending strength of the three parts converges on 6 kg/mm2 after irradiation within a range of 106 - 107 r.. Joint efficiency (= bonded part strength/base material strength) of 65 - 75% in tension and 50 - 62% in bending can be adopted. Fracture of the base material and of the Welded part are similar, and prove high bonding strength. (author)

  3. Evaluation by EPR of potential antioxidant components of 60Co-irradiated varieties of soybean

    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 60Co 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)

  4. Characteristic evaluation of papain irradiated with 60Co γ-rays for the purpose of sterilization

    To establish irradiation sterilization method for hybrid biomedical materials containing bioactive molecules together with artificial polymers, we employed dry powder and aqueous solution of papain as a model and examined radiation tolerance with 60Co γ-rays. The dry powder and frozen aqueous solution showed significant resistance after 30-kGy irradiation, indicating that commercial irradiation sterilization method for disposable medical supplies was applicable. Unfrozen aqueous solutions (10mg/ml), in contrast, showed significant drop of enzymatic activity within the early period of irradiation (ca. 0.5kGy) but 40% of the activity was recovered at ca. 3-kGy before total inactivation at 15kGy. Taking various conditions including dose rate, concentration of enzyme, oxygen and nitrogen bubbling into irradiation inactivation experiments, we demonstrated that inactivation of papain could be controlled under anoxic condition, such as nitrogen bubbling, increasing sample volume at high dose rates and high concentration of enzyme where dissolved oxygen was consumed rapidly. It is suggested that radiation inactivation of papain in the aqueous solution was occurred through reversible oxidation of the sulfhydryl group at the active site by free radicals derived from radiolysis of water and dissolved oxygen. (author)

  5. Effect of 60Co γ-rays irradiation on antioxidant enzymes activities in transgenic and non-transgenic tobacco seedlings

    Changes of activities of antioxidant enzymes in pprI-transgenic tobacco seedlings and non-transgenic tobacco seedlings after different doses 60Co γ-rays irradiation were studied. The results showed that the activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in pprI-transgenic tobacco seedlings and non-transgenic tobacco seedlings were gradually increased after different doses 60Co γ-rays irradiation. The activity of SOD was to the maximum at 100 Gy treatment, but the activity of POD and CAT at 300 Gy treatment, and then these three antioxidant enzymes gradually decreased with the increase of irradiation dose. Quantitative real-time PCR analysis also revealed that the over-express of these antioxidant enzymes were induced after different doses 60Co γ-rays irradiation and were consistent with the variance of their enzymic activities, which enhanced the tolerance of tobacco against irradiation. (authors)

  6. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of 60Co

    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 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 60 Co source. The native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD50 and biodistribution. The native and irradiated crotamine were labelled with 29.6 MBq of 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 106 cpm/mouse) of 125 I native crotamine or with 0.4 mL (1.3 x 106 cpm/mouse) of 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 muscle and they did not pass the blood - brain

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

    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.)

  8. Proteomics study of progeny of normal human liver cells irradiated by 60Co γ-rays

    Objective: To characterize the differential protein expression in the progeny of human liver cells 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-irradiation. 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 ion-top off light-mass spectrometry (MALDI-TOF MS) analysis, including 4 up-regulated and 13 down-regnlated proteins. Conclusions: The differentially expressed proteins profile could be significantly altered in the progeny of irradiated cells. The proteomics approach has the potential to detect the protein changes relevant to radiatian-induced genomic instability (RIGI). Further study of differentially expressed proteins would likely reveal the molecular mechanisms of gene expression in RIGI. (authors)

  9. Effects of flavonoids of Astragali Complanali against damage induced by 60Co γ-ray irradiation

    Objective: To study on the radioprotective effect of flavonoids of Astragali Complanali on γ-ray induced injury. Methods: Female mice were fed with FAC at different doses for 17 days, positive control were administered with Leucogen Tablets, irradiation and negative control were administered with distilled water only, then all mice except the negative control group were exposed to 6 Gy 60Co γ-ray for whole-body-irradiation at the 7th day, observe the protective effect of FAC against damage of irradiation and its effects on antioxidant system and immune function. Results: The 21-day survival rate of FAC-protected mice were higher than that in the control group, blood cell counts of FAC-protected mice were higher than those in the control group such as WBC, RBC, PLT, HGB and LY counts; superoxide dismutase and lymphocyte proliferation index of FAC-protected mice were much higher than those in the control group and malondiadehyde counts lower. Conclusion: These results suggest that FAC can alleviate irradiation damage induced by gamma-ray, might be associated with ameliorating antioxidant level and immune function. (authors)

  10. Dose-response for bone regeneration after single doses of 60Co irradiation

    The Bone Growth Chamber (BGC) methodology was used to establish a dose-response relationship for regeneration of mature bone tissue after irradiation of 5, 8, 11, 15 and 25 Gy single dose 60Co. The BGC, which is a titanium implant, was inserted in the proximal tibial metaphyses, bilaterally, of a rabbit immediately following local irradiation to one tibia. Each animal thus served as its own control. During a healing period of 4 weeks, the two canals penetrating the implant became filled with more or less newly formed bone. At the end of the healing period, the implants were removed and taken apart and the newly formed bone was collected and its volume measured by microradiography and microdensitometry. It was found that in the dose range of 5 to 8 Gy bone regeneration was reduced by about 20% as compared to non-irradiated controls. Between 8 and 11 Gy, there was a critical range in that a small increase in dose resulted in a greatly reduced bone formation. At 11 Gy and above, the depression in bone formation, as compared to non-irradiated controls, was about 65 to 75%

  11. Decomposition of ρ-nonylphenols in water by 60Co γ-ray irradiation

    ρ-Nonylphenols (NPs), one of endocrine disrupting chemicals, are used as plastic flexibilizers or nonionic surfactants, and widely released into the water environment. Hydroxyl radicals produced from water molecules by γ-ray irradiation have high oxidation reactivity. Recently, treatments with the hydroxyl radicals have drawn much attention to conserve the water environment. In this study, decompositions of NPs in water were investigated using hydroxyl radicals by 60Co γ-rays irradiation. The concentrations of the NPs at initial concentration from 45 to 1000 nM were decomposed by γ-ray irradiation. Qualitative and quantitative analyses of NPs were carried out by high performance liquid chromatography. The decomposition curves of NPs at each initial concentration were analyzed as single exponential functions. Alkylphenol activity of aqueous NPs solution, which was estimated by enzyme-linked immunosorbent assay, implies the irradiation products have alkylphenol activity. Two products having molecular weight of 236 were investigated by liquid chromatography-mass spectrometry, and were considered to be ρ-nonylcatechol and 1-(ρ-hydroxyphenyl)-1-nonanol on the basis of the oxidation mechanisms of ρ-cresol and 4-ethylphenol. (author)

  12. Irradiation effect on enzymatic activity of papain with 60Co-γ rays

    An investigation was made on the durability of enzyme activity against 60Coirradiation 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 O2 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 N2 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.)

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

    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)

  14. Effects of 60Co γ-ray irradiation on growth characters of Chamaecrista seeds

    The seeds of 5 Chamaecrista varieties were irradiated by 60Co γ-ray of 300 Gy and the effects on M1 generation were studied. The results showed that the emergence of 5 Chamaecrista varieties decreased in some degree ; the stem-length of variety 34721 was significantly decreased, the stem-diameter of variety 2219 and the leaf-width of variety 2219 were significantly increased. The number of branch, leaf and leaf-length had no significant difference, but there were many black blots in the leaf during early period; the dry-weight of aerial part changed in two directions, either increased (92985) or decreased (34721). The total N of variety 2217 were significantly increased and the total P of variety 92985 were significantly decreased. The squaring stage, initiate flower stage, full bloom stage, pod-bearing stage, peak pod setting stage and maturing stage had changed in two direction, either early, or late

  15. Evaluation of myotoxic activity of Bothropstoxin-1 irradiated with 60Co gamma rays

    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 NaNO3 and t-butanol, present selective effects on specific radical from water radiolysis. The NaNO3 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 60Co 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 NaNO3 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)

  16. Influence of 60Co irradiation on the mandible of adult rabbit

    This study was performed in order to observe the effect of 60Co γ-ray irradiation (5000, 8000 and 10000R) on rabbits' mandible, for as long as possible, approximately 18 months. Radiographical and histopathological studies were done after irradiation. The upper anterior teeth of all experimental animals showed elongation, lateral flection and diasthema. The lower anterior teeth showed shortening or disappearance of the crowns and resorption of the root apex in all. These teeth were lost eventually. Molar teeth disclosed shortening of crowns and irregular and partial loss on the surface of the dentine. Pulp chambers were extremely narrowed. These changes were most conspicuous in the 10,000R irradiation group. Mandibular fractures occurred in 13 cases, which include 3 cases with 5,000R, 4 cases with 8,000R and 6 cases with 10,000R. The alveolar bones were resorped, and were replaced with mandibular bone trabeculae. Various types of ankylosis of root surface and mandibulars were seen. These changes were more frequently noted in the molar regions that the anterior regions and in the groups with higher doses and longer days after irradiation. Bone trabeculae and cortex of the mandibles were resorped in the 3 irradiation groups in the early stage, but regeneration and thickening of the bones occured later. The usual case was that the anterior bone marrow became more gelatinous and the molar marrow became more fibrous. Hyperemia and abscess formation were recognized in some cases. Although in the molar regions these pathological changes were conspicuous in proportion to the amount of dose, in the anterior regions, the same changes were more conspicuous in the 5,000R irradiation group than in the 8,000R group. (J.P.N.)

  17. /sup 60/Co irradiation for sterilization of veterinary mastitis products containing antibiotics and steroids

    Tsuji, K.; Kane, M.P.; Rahn, P.D.; Steindler, K.A. (Upjohn Co., Kalamazoo, MI (USA))

    1981-01-01

    Effects of /sup 60/Co irradiation for sterilization of veterinary mastitis products were evaluated. The mastitis products which were examined contained various combinations of antibiotics and steroids suspended in peanut oil vehicle. Bioburden data indicated that the unirradiated products were only occasionally contaminated with microorganisms. The D-values of the nonsterile product and environmental isolates were 0.028, 0.15, 0.017, and 0.018 Mrads for Aspergillus fumigatus, Penicillium oxalicum, Pseudomonas aeruginosa, and Pseudomonas maltophilia, respectively. The D-value of the biological indicator organism, Bacillus pumilus spores, in the vehicle was 0.27 Mrads. Thus, an irradiation dose of 1.6 Mrads would be sufficient to achieve six log cycles of destruction of the biological indicator organism. The minimum absorbed irradiation dose of 2.5 Mrads preferred by many countries for sterilization would achieve 9.3 log cycle destruction of the indicator organism and guarantee a probability of 1 x 10/sup -15/ assurance for the most radio-resistant product isolate, Penicillium oxalicum. In order to examine short and long term chemical stabilities of active components, stability indicating high-performance liquid chromatographic (HPLC) methods for the determination of several of the antibiotics and steroids were developed. The rates of degradation and radiolytic degradation schemes for the majority of the compounds were elucidated.

  18. Effect of 60Co gamma-ray irradiation on dilute aqueous solutions of surfactants

    Present work deals with the effects of gamma irradiation from 60Co γ-ray source upon aqueous solutions of three kinds of surfactants. When dilute aqueous solutions of sodium dodecyl sulfate (SDS, anionic), cethyl trimethyl ammonium chloride (CTAC, cationic), and polyoxyethylene lauryl ether (POE, non-ionic) were irradiated with γ-rays at a room temperature, the residual concentration, products, surface tension, and forming power were examined by colorimetric method, IR spectrophotometric method, gaschromatography, Ross-Miles method, and Traube's stalagmometer etc. These surfactants were decomposed by the irradiation and thus the surface tension increased and the forming power, on the contrary, decreased with dose. Radiation chemical yields (G-value) of the degradation were about 1 for the solutions of SDS and CTAC, and about 0.3 for the POE solution. From the experimental results, it was found that following chemical reactions seem to occur followed by the radiolysis of water: a) bond cleavage of ester for SDS, of CN for CTAC, and of oxyethylene for POE, b) hydrogen abstraction from the surfactants, c) production of CO bond in the presence of dissolved oxygen. (auth.)

  19. Chemical changes in the chloroform-paraffin system irradiated by 60Co gamma-rays, 1

    It has been reported that the chloroform-paraffin-dye system have excellent sensitivity for radiation as a solid chemical dosimeter or a phantom. However, the chemical changes in the irradiated system are not examined in detail. In the present study, the effect of paraffin on changes in the above system of a liquid state irradiated by 60Co γ-rays was examined by using various normal paraffin, and the other variable factors on the changes were done. When the chloroform solution and the solution containing 25 per cent of paraffin by volume with 5.0 x 15-5 mol/liter of Methyl Yellow as a dye were irradiated by 2000 R, G values for the formation of hydrogen chloride in the both solutions were 8.4 and 10.8, respectively, and were little affected by the kind of those, from C6 (hexane) to C36 (hexatria-contane). These results suggest that chlorine radical formed by radiolysis of chloroform may react with hydrogen atom from paraffin, thereby increasing the amount of hydrogen chloride. Presence of oxygen increased G value of the chloroform solution from 7.6 to 8.4, but did little that of the solution containing paraffin. (author)

  20. 60Co irradiation for sterilization of veterinary mastitis products containing antibiotics and steroids

    Effects of 60Co irradiation for sterilization of veterinary mastitis products were evaluated. The mastitis products which were examined contained various combinations of antibiotics and steroids suspended in peanut oil vehicle. Bioburden data indicated that the unirradiated products were only occasionally contaminated with microorganisms. The D-values of the nonsterile product and environmental isolates were 0.028, 0.15, 0.017, and 0.018 Mrads for Aspergillus fumigatus, Penicillium oxalicum, Pseudomonas aeruginosa, and Pseudomonas maltophilia, respectively. The D-value of the biological indicator organism, Bacillus pumilus spores, in the vehicle was 0.27 Mrads. Thus, an irradiation dose of 1.6 Mrads would be sufficient to achieve six log cycles of destruction of the biological indicator organism. The minimum absorbed irradiation dose of 2.5 Mrads preferred by many countries for sterilization would achieve 9.3 log cycle destruction of the indicator organism and guarantee a probability of 1 x 10-15 assurance for the most radio-resistant product isolate, Penicillium oxalicum. In order to examine short and long term chemical stabilities of active components, stability indicating high-performance liquid chromatographic (HPLC) methods for the determination of several of the antibiotics and steroids were developed. The rates of degradation and radiolytic degradation schemes for the majority of the compounds were elucidated. (author)

  1. Analysis of the frequency of unstable chromosome aberrations in human lymphocytes irradiated with 60Co

    The aim of this study was to analyze the frequency of unstable chromosomal aberrations induced by gamma radiation from a 60Co source at two different doses. Samples were obtained from a healthy donor and exposed to 60Co 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

  2. Perna perna (LINNAEUS, 1758) mussels irradiated by 60CO gamma rays cytotoxicity evaluation

    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 60Co 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)

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

    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)

  4. Influence of rhTPO on hematopoiesis in mice irradiated with 60Co γ-ray

    Objective: Thrombopoietin, a major physiological regulator of megakaryocytopoiesis, has potent effects on megakaryocytopoiesis. With a view to finding a new therapeutic modality for bone marrow injury-induced thrombocytopenia, the authors studied the biological activity of rhTPO in vivo. Methods: The authors recombined hTPO by means of RT-PCR and eukaryotic expression. The rhPTO was administered to 5.0 Gy 60Co γ-ray irradiated male mice, once per day for 20 consecutive days. Peripheral blood counts were monitored and bone marrow was assayed for clonogenic activity. Results: Circulating platelet counts and CFU-MK of the rhTPO-treated mice increased significantly in contrast with the control group. Conclusion: These results show that rhTPO can restore platelets and CFU-MK of irradiated mice in vivo. Clearly, the growing understanding of the biology of TPO will lead to important new in-sights into megakaryocytopoiesis and to improvement in clinical treatment of bone marrow failure

  5. Toxoplasma gondii vs ionizing radiation: intestinal immunity induced in C57bl/6j mice by irradiated tachyzoites

    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)

  6. Biochemical and pharmacological characterization of irradiated crotamine by gamma rays of 60Co

    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 60Co 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 in

  7. 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

    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

  8. Flux and energy deposition distribution studies inside the irradiation room of the portuguese 60Co irradiation facility

    Full text: In December 2003 the irradiator of the Portuguese 60Co irradiation facility, UTR, was replenished. Eighteen new sources were loaded and the older ones (156) were rearranged. The result was an irradiator with about 10.2 P Bq of total activity. The active area of the irradiator has also increased. Now it uses twenty five of the thirty tubes of the source rack, nine more than in the previous geometry. This facility was designed mainly for sterilisation of medical devices. However it is also used for the irradiation of other products such as cork stoppers, plastics and a limited number of food and feed. The purpose of this work is to perform dosimetric studies inside the irradiation room of a 60Co irradiation facility, particularly, the flux and energy deposition distributions. The MCNPX code was used for the simulation of the facility. The track average mesh tally capabilities of MCNPX were used to plot the photon flux and energy deposition distributions. This tool provides a fast way for flux and energy deposition mapping. The absorbed dose distribution near the walls of the irradiation room was also calculated. Instead of using meshtallys as before, the average absorbed dose inside boxes lined with the walls was determined and afterwards a plot of its distribution was made. The absorbed dose rates obtained ranged from 5 to 500 Gy.h-1 depending on material being irradiated in process and the location on the wall. These positions can be useful for fixed irradiation purposes. Both dosimetric studies were done considering two different materials being irradiated in the process: cork stoppers and water, materials with quite different densities (0.102 and 1 g.cm-3, respectively). These studies showed some important characteristics of the radiation fields inside the irradiation room, namely its spatial heterogeneity. Tunnelling and shadow effects were enhanced when the product boxes increases its density. Besides a deeper dosimetric understanding of the

  9. The effect of 60Co γ-ray irradiation on the growth and regeneration of Cymbidium sinense rhizome

    The effect of 60Co γ-ray irradiation on growth of Cymbidium sinense rhizome and shoot regeneration were studied. The results showed that irradiation with low dose (2, 5 and 8 Gy) promoted the growth of Cymbidium sinense rhizome, while high dose (≥ 10 Gy) inhibited the growth. Shoot differentiation of rhizome was not affected by irradiation of low dose. Biochemical analyses indicated that the soluble protein content of rhizome irradiated with low dose was higher than that of CK, irradiated with 2 and 5 Gy seemed to reduce the activity of peroxidase, while irradiated with 8 Gy increased the activity of peroxidase

  10. Effects of 2.0 Gy of 60Co gamma rays irradiation on rat embryos

    Pregnant rats of Donryu strain were exposed to a whole-body 60Co γ 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 60Co γ 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.)

  11. Effects on agronomic traits of M1 by pollen of upland cotton irradiated by 60Co-γ ray

    [Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-? Ray of varied doses. [Method] Ripe pollen grains of upland cotton were irradiated by 60Co-γ Ray with doses of 5, 10, 15, and 20 Gy, respectively, to learn radiation effect and select appropriate dose. [Result] Most properties of M1 obviously showed variation when dose was over 10 Gy; vitality, growth, and fertility were greatly inhibited when dose was 15 Gy which was almost semi-lethal concentration, and variation species were richest at the same time, which provided materials for practical breeding. [Conclusion] 60Co-γ Ray of 15 Gy was more suitable for inducing research for ripe pollen grains of upland cotton

  12. Detection and thermoluminescence of coriander (Coriandrum sativum L.) irradiated with 60Co

    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 μm 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 60Co. 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)

  13. 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

    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)

  14. Mutant strain screening by 60Co γ-rays irradiation and its cellulase enzyme produce condition

    A mutant strain A50 with high cellulase activity was induced and isolated by using 60Co γ-rays irradiation from the initial Penicillium decumbens A10. The optimum fermentation conditions of A50 were investigated through orthogonal designing experiment, the major carbon resource 5%, the ratio between wheat bran and corn straw 1:1, the concentration of glucose as supplemental carbon 0.1%, the concentration of (NH4)2HPO4 as supplemental nitrogen resource 0.2%, the initial pH of liquid medium 5.0, the inoculated amount for fermentation 10% and the concentration of Tween-80 0.1%, 30 ml initial media filled in the 300 ml flask with culture condition of 32 degree C and 200 r/min. Under the optimum conditions mentioned above, the highest activities of cellulase and filter paper enzyme were 27.28 and 1.98IU/ml at 60 h fermentation, respectively, which was 33.2% and 45.59% higher than those of the initial strain. (authors)

  15. Efficacy of a 60Co irradiated vaccine for experimentally infected calves with dictyocaulus viviparus

    Dictyocaulus viviparus larvae in non-infected stage (L.1) were cultured in vitro to their infective stage (L.3) and were irradiated with 40 Krad from 60Co and used as a vaccine. The oral experimental vaccine dose was 1000 L.3/animal. Three groups were formed with 8 calves in each one: group No. 1 and group No. 2 were vaccinated at 10 weeks of age. Four weeks later group No. 1 was infected with non-irradiated 60 L.3/Kg. of animal weight 'challenge dose'. After four weeks of post-vaccination group No. 2 was revaccinated and 4 weeks later it was infected with the 'challenge dose' as the previous group. Eight calves constituted group No. 3, four in each group; they were infected with only the challenge dose respectively. Information data on respiratory and cardiac frequency, temperature, weight, and L.1 count/g. of feces were obtained from each animal three times a week. After five weeks of post-challenge all animals were slaughtered to observe anatomopathologic lessions in the heart and lungs; the number of adult Dictyocaulus viviparus present in the respiratory tract were search 't'. Student test was used for the statistical analysis. The weight increment difference between animals of group No. 1 related control group was 7Kg.; and 11.25 Kg/animal in group No. 2 respectively. The percentage of protection confered by the vaccine to the subjects in group No. 1 relative to the respectivecontrol group, was 83.2; that for the group No. 2 was 88.5 per cent. Post-morten examination revealed severe anatomopathologic lessions in the control groups; only few lessions were observed in group No. 1 and practically none in group No. 2

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

    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

  17. (60)Coirradiation affects the enzymatic antioxidant system of the citrus red mite Panonychus citri (Acari: Tetranychidae).

    Zhang, Ke; Li, Zhibin; Zhu, Shaowen; Weng, Qunfang

    2014-01-01

    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. PMID:24853454

  18. 60CoIrradiation Affects the Enzymatic Antioxidant System of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae

    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.

  19. Influence of 60Co γ irradiation on fertility of Japanese pine sawyer beetle Monochamus alternatus hope (Coleoptera: Cerambycidae)

    The fertility of the Japanese pine sawyer beetle Monochamus alternatus (Coleoptera: Cerambycidae) irradiated with 60Co γ-rays was remarkable reduced at the doses of 30Gy, 35Gy and 40Gy, especially at 40Gy. When the non-irradiated females were coupled with the irradiated males first, and then coupled with non-irradiated males, the hatchability and the fertility had little higher but lower than the control. It explained that radiation has certain influence to the female gonad. It also has difference between the hatching rate and the amount of eggs in different match. (authors)

  20. Expression of FHIT in AHH-1 cells irradiated by 60Co γ-ray and bystander effect cells

    Objective: To investigate the expression of FHIT gene in the 60Co gamma-ray irradiated human lymphocytoblast (AHH-1) cell and the bystander effect cell, and to explore the function of FHIT gene in the bystander effect of ionizing radiation. Method: Preparation of bystander effect cell model: after inadiated with different dose of 60Co gamma-ray (0, 2, 5 Gy), the directly irradiated AHH-1 cells were collected immediately by centrifugation and co-cultivated with non-irradiated cells in Transwell, forming the bystander effect group P1. In addition, some culture media supematant of directly irradiated cells were transferred to the non- irradiated cells culture medium, forming the group P2. Then cells were collected at 0, 6, 12, and 24 h after irradiation and the total RNA and protein were extracted. RT-PCR and Western blot were performed to determine the FHIT mRNA and protein level, respectively. Flow cytometry assay and cell counting were conducted to detect the alteration of cell cycle and cell proliferation, respectively at 0, 24 h after irradiation. Results: The mRNA level of FHIT gene among control cells, directly irradiated cells and bystander cells showed no obvious difference, while the FHIT protein level of the directly irradiated cells and bystander cells was significantly down-regulated compared with the control cells (F=102.45, P2 phase arrest and obviously inhibited the proliferation ability. Conclusions: 2 and 5 Gy of 60Co γ-ray irradiated AHH-1 cells can result in down regulation of the FHIT protein expression, which suggests that FHIT gene is involved in the process of bystander effect induced by irradiation. (authors)

  1. The influence of whole body 60Co-irradiation on distribution of 67Ga in tumor-bearing mice

    Since the initial findings that 67Ga has a preferential affinity for soft tissue tumors, in humans numerous suggestions have been advanced for the basic mechanism involved. The effects produced by whole-body X-irradiation on the excretion and tissue distribution of 67Ga have been reported by Swartzendruber and others. Bradley and coworkers have shown that these irradiation effects were associated with an increase in serum iron. The present investigation was undertaken in order to study the relationships between the change in the serum iron concentration and 67Ga accumulation in the tumor and soft tissues in mice bearing Ehrlich's ascites tumor. The following results were obtained. (1) The serum iron concentration was significantly decreased between 3 and 6 hours after 10 Gy (1,000 rad) dose of whole-body 60Co-irradiation. Subsequently, the serum iron levels were slowly elevated. (2) The uptake of 67Ga in the tumor and soft tissues was increased if the serum iron concentration was decreased by whole-body 60Co-irradiation during the early phase. On the contrary, if the serum iron concentration was high, the uptake of 67Ga in the tumor was decreased. (3) The excretion of 67Ga from the body was delayed if the serum iron concentration was decreased by whole-body 60Co-irradiation. However, if the serum iron concentration was high, the excretion of 67Ga from the body significantly increased. (author)

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

    Graphical abstract: -- Highlights: •Analyzing the impact of 60Co gamma radiation (low doses) in M. rosenbergii. •LD50 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 60Co gamma radiation induced morphological and histological variations in freshwater prawn Macrobrachium rosenbergii. The LD50 value of 60Co 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 the organs it is felt could

  3. Effect of irradiation using 60Co on Trichinella spiralis larvae and on the eggs and protoscolices of Echinococcus granulosus

    The effect of irradiation using 60Co on Trichinella spiralis larvae and on the eggs and protoscolices of Echinococcus granulosus was studied. A dose of 30 Gy had no effect on T. spiralis larvae and on the eggs and protoscolices of E. granulosus. Irradiation of free T. spiralis larvae from muscle in normal saline exposed to 90 Gy and higher doses produced loss of infection in mice. There was reduction in the infectivity of eggs and protoscolices of E. granulosus by irradiation at a dose of 120 Gy, while there was complete loss of activity at a dose of 500 Gy. (author). 5 refs, 2 figs

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

    Danielsson, Anna; Claesson, Kristina; Parris, Toshima Z; Helou, Khalil; Nemes, Szilárd; Elmroth, Kecke; Elgqvist, Jörgen; Jensen, Holger; Hultborn, Ragnar

    2013-01-01

    Purpose: The aim of this study was to identify gene expression profiles distinguishing alpha-particle (211)At and (60)Co irradiation. Materials and methods: Gene expression microarray profiling was performed using total RNA from confluent human fibroblasts 5 hours after exposure to (211)At labeled...... 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...... transcription, cell cycle regulation, and cell cycle arrest, whereas mitosis, spindle assembly checkpoint, and apoptotic chromosome condensation were uniquely enriched for alpha particle irradiation. Conclusions: LET-dependent transcriptional modulations were observed in human fibroblasts 5 hours after...

  5. Study on irradiation-induced-degradation of five fishery drugs in aqueous solution by 60Co γ-rays

    The degradation of five kinds of fishery drugs in aqueous solution irradiated by 60Co γ-rays at the absorbed dose of 0-10 kGy was investigated. The effects of acid/base, degassing and temperature on the degradation of fishery drugs were studied. The results show that fishery drugs can be degraded significantly with 60Co γ-rays irradiation,and the higher absorbed dose the higher degradation efficiency. The degradation percentage increases with the decrement of initial concentration of fishery drugs. More than 90% degradation of five fishery drugs has been achieved at absorbed dose of 8 kGy. The effects of acid/base and degassing environments on the degradation of fishery drugs are different. The lower temperature can inhibit remarkably the degradation of fishery drugs in aqueous solution. (authors)

  6. Regulation of Guzhen Fang on neuroendocrine and immune systems of rats irradiated with 60Co γ-rays

    Rats were singly irradiated with 6.8 Gy 60Co γ-rays. The changes of monoamine neurotransmitters in hypothalamus, luteinizing hormone (LH), estradiol (E2), testosterone (Ts) in serum, β-endorphin (β-EP) in plasma and the immunologic function of lymphocytes in spleen of rats were observed. The effects of Guzhen Fang (a traditional Chinese Medical prescription) composed of polygoni multiflori, cistanche salsa etc, were studied. The results were as follows: 1. After the rats were irradiated with 60Co γ-rays, the contents of monoamine neurotransmitters in hypothalamus decreased, β-EP in plasma increased, and the hyperfunction of hypothalamus-hypophysis-gonadal (HHG) axis and the hypofunction of lymphocytes appeared. The Guzhen Fang, however, could improve the above changes obviously. 2. Si Junzi Tang (also a traditional Chinese medical prescription) could also increase the immunologic function as Guzhen Fang did, but its effect on neuroendocrine system is not significant

  7. Effect of 60Co γ-rays irradiation pretreatment on callus inductivity and differentiation of strawberry anther

    Strawberry buds, in which a majority of pollen had single nuclear keeping to the side, were pretreated by 60Co γ-rays irradiation at different doses. The irradiation effect on the callus inductivity and plant differentiation rate of strawberry anther were studied. The results indicated that the pretreatment by 60Co γ-rays could increase the anther callus inductivity and plant differentiation rate significantly, and 20 Gy was the best dose. The callus inductivity of Akihime and Toyonoka increased by 39.09% and 35.68%, respectively, compared with the no-pretreatment materials. On the same media, the plant differentiation rate of Akihime and Toyonoka were also increased by 6.67%-6.72% and 4.73%-6.45%, respectively, compared with the two varieties of no-pretreatment. (authors)

  8. Prevention and control of pneumonia induced by 60Co γ irradiation of thorax in rats of selenium-enriched Spirulina

    From the indicators including body weight, wet lung weight, percentage of T lymphocytes in peripheral blood, the cell count of broncho-alveolar lavage fluid and its chemoluminescence, contents of hydroxyproline and collagen mRNA synthesis in lung, and pathological changes in pulmonary tissue, the preventive and curative effects of selenium-enriched Spirulina on the pneumonia induced by 60Co γ irradiation of thorax in rats were demonstrated during 90 days of observation

  9. Grafting of synthetic polyelectrolyte onto polymer surfaces--comparison of glow discharge and 60Co-gamma-irradiation method

    Water soluble polyelectrolyte synthesized from natural rubber contains sulfamate and carboxylate groups similar to that of heparin. It is observed that synthetic heparinoid polyelectrolyte is capable of inhibiting blood coagulation. In the present study, we attempted to graft the same onto polystyrene and polymethylmethacrylate surfaces using glow discharge technique and 60Co-gamma-irradiation method, and the surfaces were compared with respect to water contact angle and platelet adhesion parameters. Heparinized surfaces are also evaluated for relative comparison

  10. Studies on the function of pokeweed mitogen inducing lymphocytes and 60Co γ-ray irradiation effects

    T and B lymphocytes in human periphery blood were seperated by rosette procedure. After lymphocytes were labelled with T4+ McAB, T4+ and non-T4+ lymphocytes were isolated by cell affinity chromatography method. When parts of T, B, T4+ and non-T4+ cells were exposed to 10 Gy 60Co γ-rays, the function of poke weed mitogen (PWM) and 60Co-rays irradiation effect on lymphocytes were investigated by technique of 3H-TdR incorporation. The results showed that PWM can induce both T and B lymphocytes but B lymphocytes were more sensitive to PWM. The response of B lymphocytes to PWM was the same as that of non-T4+ cells, the response of T4+ cells to PWM was the lowest. DNA synthesis of both T and T4+ lymphocytes were synergistic to B lymphocytes. The synergistic effect in T and B lymphocytes were irradiated by 10 Gy 60Co γ-rays, the synergistic effect disappeared. Neither synergistic nor suppressive effect was found between non-T4+ and B lymphocytes. When T4+, B and non-T4+ lymphocytes had been exposed to 10 Gy irradiation, the percentage suppression of 3H-TdR incorporation between B and non-T4+ lymphocytes had no significant difference but was higher than that in T4+ lymphocytes

  11. Study on the down-regulation of PKCα by tamoxifen combined with 60Co γ-irradiation in glioma cells

    The mechanism of radio-sensitizing effect of tamoxifen on the influence of PKCα expression has been explored by tamoxifen combined with 60Co γ-irradiation in human glioma cells. The protein expression of PKCα and CyclinD1 were detected by using Western-Blot. The level of DNA strand breaks was detected by the alkaline single-cell gel electrophoresis assay. The results demonstrated that the combination of tamoxifen and 60Co γ-irradiation could reduce expression of PKCα and CyclinD1. And it also enhanced the radiation-induced DNA damage and attenuated the repair of damaged DNA. The above results reveal that the combination of tamoxifen and 60Co γ-irradiation can enhance the downregulation of the expression of PKCα and the induction in the low expression of CyclinD1 as well at the delay of DNA repair. All these may be related to the impairment of the radioresistance of SHG-44 cells by tamoxifen. (authors)

  12. Absorbed dose response of Al2O3 dosimeter irradiated by 60Co γ spectrum source capture and collimators

    Objective: To investigated the absorbed dose response of Al2O3 dosimeter in water phantom irradiated by 60Co γ spectrum source. Methods: The EGSnrc simulation program code DOSRZnrc was used to calculate the absorbed dose of the Al2O3 dosimeter and that of the equivalent volume of water in the corresponding position, as well as the absorbed dose conversion factor, irradiated by 60Co photon beams in a water phantom. Simulations were done for a cylindrical geometry dosimeter (diameter 0.4 cm and height 0.1 cm) and the dosimeter was placed at the centre of the water phantom at different depths. Results: The average absorbed dose conversion factor is 1.143±0.006 and changes little with the depth of the dosimeter in the water phantom, and the deviation is less than 1.0%. Conclusion: The absorbed dose response of Al2O3 dosimeter irradiated by 60Co γ spectrum source is steady and is independent on the depth of the dosimeter in water phantom in this research. (authors)

  13. Effect of 60Co-irradiation on the development and immunogenicity of Plasmodium berghei sporozoites in Anopheles stephensi mosquitoes

    Smrkovski, L.L.; McConnell, E.; Tubergen, T.A.

    1983-10-01

    Protection conferred to mice by Plasmodium berghei sporozoites increased significantly when the time interval between 60Co-irradiation of the infected mosquitoes and harvest of sporozoites increased. One thousand sporozoites conferred no protection against challenge if harvested on the day of irradiation, but protected 60% of recipient mice when harvested 28 days postirradiation. When the time between feeding of mosquitoes and irradiation was varied, sporozoites from mosquitoes irradiated 3 days after feeding were infective for mice. Sporozoites from mosquitoes irradiated on day 10 postfeeding were not infective, but were immunogenic. In all experiments a decline occurred in the number of recoverable sporozoites over a 28-day period postirradiation to less than 10% of the yield on the day of irradiation.

  14. Effects of accumulated 60Co γ-ray irradiation on the small molecular metabolites in rats urine

    Objective: To explore the effects of accumulated 60Co γ-ray irradiation on small molecular metabolites in rats urine. Methods: Ten healthy male SD rats were irradiated by 60Co γ-rays in 5 days and the accumulated doses were 0, 0.2, 0.4, 0.6, 0.8, 1.0 Gy, respectively. The metabolites in urine of different groups were measured with 1H-NMR combined with principal components analysis (PCA) and partial least square discriminate analysis (PLS-DA). Results: The metabolites in rat urine were obviously changed after irradiation. Compared with control group, the amount of acetoacetate decreased after irradiation (t=29.7-30.7, P<0.05), but its relative level was stable when the dose increased (P>0.05). Meanwhile,the relative level of hippuric acid increased (t=4.4-21.6, P<0.05) especially when the accumulated dose was higher than 1 Gy (t=21.6, P<0.05). The relative level of proline, taurine and trimethylamine-N-oxide increased after irradiation with the same trend(t=3.5-13.4, 4.7-11.5, 2.9-12.7, P<0.05). Conclusions: The acetoacetate, hippuric acid, proline, taurine, and trimethylamine-N-oxide may be applicable for biomarkers of accumulative irradiation on rat. (authors)

  15. Effects of 60Co γ-ray irradiation on expression of surface antigens in endothelial cells of human umbilical veins

    Culture of endothelial cells of human umbilical veins and avidin-biotin peroxidase complex (ABC) immunochemical technique were used in the experiment to detect the surface antigens in endothelial cells. Endothelial cells separated from five umbilical cords in original culture were divided into two groups, irradiated and non-irradiated. The cells were irradiated with 15 Gy of 60Co γ-rays at dose rates of 21.78 cGy/min. Then antigens RBC A, HLA-ABC, HLA-DR, CD4 and CD8 were assayed for both groups by the method of ABC. The results showed that the values of integrated optical density (IOD) for the surface antigens in the irradiated cells were lower than those in the non-irradiated cells with the difference in antigen expression in endothelial cells being significant (P<0.05) between the two groups

  16. 60Co-irradiation as an alternate method for sterilization of penicillin G, neomycin, novobiocin, and dihydrostreptomycin

    Tsuji, K.; Rahn, P.D.; Steindler, K.A.

    1983-01-01

    The effects of the use of 60Co-irradiation to sterilize antibiotics were evaluated. The antibiotic powders were only occasionally contaminated with microorganisms. The D-values of the products and environmental isolates were 0.028, 0.027, 0.015, 0.046, 0.15, 0.018, and 0.19 Mrads for Aspergillus species (UC 7297, 7298), A. fumigatus (UC 7299), Rhodotorula species (UC 7300), Penicillium oxalicum (UC 7269), Pseudomonas maltophilia (UC 6855), and a biological indicator microorganism, Bacillus pumilus spores (ATCC 27142). An irradiation dose of 1.14 Mrads, therefore, was sufficient to achieve a six-log cycle destruction of B. pumilus spores. Based on the bioburden data, a minimum irradiation dose of 1.05 Mrads was calculated to be sufficient to obtain a 10(-6) probability of sterilizing the most radioresistant isolate, Pen. oxalicum. To determine the radiolytic degradation scheme and the stability of the antibiotics following irradiation, high-performance liquid chromatographic (HPLC) methods were developed. The resulting rates of degradation for the antibiotics were 0.6, 1.2, 2.3, and 0.95%/Mrad for penicillin G, neomycin, novobiocin, and dihydrostreptomycin, respectively. Furthermore, radiolytic degradation pathways for the antibiotics were identified and found to be similar to those commonly encountered when antibiotics are subjected to acidic, basic, hydrolytic, or oxidative treatments. No radiolytic compounds unique to 60Co-irradiation were found.

  17. 60Co-irradiation as an alternate method for sterilization of penicillin G, neomycin, novobiocin, and dihydrostreptomycin

    The effects of the use of 60Co-irradiation to sterilize antibiotics were evaluated. The antibiotic powders were only occasionally contaminated with microorganisms. The D-values of the products and environmental isolates were 0.028, 0.027, 0.015, 0.046, 0.15, 0.018, and 0.19 Mrads for Aspergillus species (UC 7297, 7298), A. fumigatus (UC 7299), Rhodotorula species (UC 7300), Penicillium oxalicum (UC 7269), Pseudomonas maltophilia (UC 6855), and a biological indicator microorganism, Bacillus pumilus spores (ATCC 27142). An irradiation dose of 1.14 Mrads, therefore, was sufficient to achieve a six-log cycle destruction of B. pumilus spores. Based on the bioburden data, a minimum irradiation dose of 1.05 Mrads was calculated to be sufficient to obtain a 10(-6) probability of sterilizing the most radioresistant isolate, Pen. oxalicum. To determine the radiolytic degradation scheme and the stability of the antibiotics following irradiation, high-performance liquid chromatographic (HPLC) methods were developed. The resulting rates of degradation for the antibiotics were 0.6, 1.2, 2.3, and 0.95%/Mrad for penicillin G, neomycin, novobiocin, and dihydrostreptomycin, respectively. Furthermore, radiolytic degradation pathways for the antibiotics were identified and found to be similar to those commonly encountered when antibiotics are subjected to acidic, basic, hydrolytic, or oxidative treatments. No radiolytic compounds unique to 60Co-irradiation were found

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

    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

  19. Suppression by ellagic acid of 60Co-irradiation-induced lipid peroxidation in placenta and fetus of rats

    The effect of ellagic acid, a component of Eucalyptus maculata, on lipid peroxidation was examined in placenta and fetus of pregnant rats irradiated with 60Co. The increase in lipid peroxide levels by the irradiation of the placenta and fetus brain as well as those of the serum and organs of mother was suppressed by treatment of the mother rats with ellagic acid. This suppressing effect found in placenta and fetus was significantly correlated with that found in mother rats. Moreover, ellagic acid suppressed the morphological changes such as degeneration in the endothelial cells of placenta and liver cells of fetus caused by the irradiation and improved the survival rate after the irradiation. These suppressing effects of ellagic acid were approximately the same as those of α-tocopherol. (author)

  20. A general review on the effects of 60Co γ-rays irradiation on vitamin C in fruits and vegetables

    Vitamin C is a nutrient component in fruits and vegetables, it's also an important bioactive substance in human body, and there are also many factors that affect the contents of vitamin C in fruits and vegetables. There papers reported that 60Co γ-rays irradiation has effects on vitamin C in fruits and vegetables, but the effect degree has some differences. Some reports says the contents of vitamin C in fruits and vegetables could be significantly reduced by irradiation, while some literatures reported that irradiation at low doses had no significant effect. The content of vitamin C in fruits and vegetables could be influenced by various factors, such as ascorbic oxidative enzyme, chemical composition, irradiation dose, irradiation environment, physiological metabolism of fruits and vegetables, etc. Irradiation treatment is an important preservation technique of fruits and vegetables. Though there were some effects of irradiation on vitamin C of fruits and vegetables, it would not influence the applications of irradiation technology in the fruit and vegetable storage, because the effects of irradiation on vitamin C could be avoided or minimized through appropriate technical treatment. This paper tries systematically analyses and summarizes the results of related investigation and provides a helpful reference in scientific applications of irradiation technology on fruits and vegetables preservation. (authors)

  1. Infection of tissue-culture cells with 60Co gamma-irradiated malaria sporozoites

    Plasmodium berghei sporozoites, attenuated by radiation from a 60Co source (8 or 15 krads) retain the ability to enter WI38 human embryonic lung cells in vitro. During the first 24 hours of incubation, the sporozoites appear to undergo normal development into exoerythrocytic trophozoites. Further development appears abnormal, although the trophozoites persist in culture cells for at least 48 hours. Parasite reactivities to fluorescent-labelled, sporozoite-specific antisera are normal up to 48 hours in culture. These observations suggest that sporozoites used in vaccine preparations may enter host cells and transform into exoerythrocytic trophozoites in vivo, but that maturation of the exoerythrocytic stage may be incomplete. (author)

  2. Dominant lethal mutation induced by continuous irradiation of 60Co gamma rays in mice

    Female and male mice were exposed to 60Co gamma rays for 10 days, the accumulative doses were 0.396-2.024 and 0.462-2.552 Gy respectively. The number of dominant lethal mutations was calculated as follows: PRE = CL - (ED + LD + VIA). The results showed that Preimplantation Loss (PRE) ranged from 1.222 to 3.714 for female mice and 0.0345 to 2.2308 for male mice. In both cases a linear dose-effect relationship was observed. The PRE of oocytes is 1.66 times higher than that of spermatids

  3. Study of the ionization of alkane-electron scavenger reactant mixtures irradiated by 60Co gamma rays

    This study deals with ionization of alkane-electron scavenger reactant mixtures, irradiated by 60Co γ-rays. It is shown that the extrapolated free-ion yields (extrapolated yield method) decrease with the reactant concentration. On the basis of ONSAGER model and theoretical treatment of MOZUMDER, the cross sections of epithermal electron attachment in hexane, cyclohexane, 2,2-dimethylbutane, cyclopentane, 2,2,4-trimethylpentane for CCl4, C7F14, C6H5Br, C6H5Cl, C6F14, (C6H5)2 are determined. A comparison between gas-phase and liquid-phase cross sections is established

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

    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)

  5. Effect of combination of STAT3 RNAi and 60Co γ-irradiation on U251 cell proliferation

    Objective: To construct signal transduction and activators of transcription 3 (STAT3) small interference RNA (siRNA) expression vector and to study its effect on STAT3 expression and U251 cell line proliferation. Methods: STAT3 specific 19 bp oligonucleotides were designed and synthesized. These oligonucleotides were annealed to form the double strand DNA fragments and these fragments were cloned into Psilence2.1-U6-H1 vector. The recombinant of STAT3-siRNA expressing construction was confirmed by Hind III and BamH I double digestion and sequencing. The STAT3-siRNA was transfected into U251 cell. The inhibitory effect of STAT3-siRNA construction was tested by Western blot. Cellular proliferation activities were measured by tetrazolium bromide (MTT) colorimetry. Cloning efficiency and MTF were used to confirm the radiation dose. Results: STAT3-siRNA expression vector was successfully constructed, and it could effectively down-regulate the protein levels of STAT3 in transfected U251 cell line; and the radiation dose was confirmed to 2 Gy. U251 cells transfected with STAT3-siRNA expression vector showed lower cellular proliferation compared with non-transfected U251 cells (P60Co γ-irradiation showed lower cellular proliferation compared with non-irradiated U251 cells (P60Co γ irradiation can enhance the inhibitory efficiency. (authors)

  6. Regulation of photosynthetic performance and antioxidant capacity by 60Co γ-irradiation in Zizania latifolia plants

    The aim of the present work was to investigate the photosynthetic performance and antioxidant enzyme activities in response to γ-irradiation of an aquatic plant Zizania latifolia. The Z. latifolia seedlings at 6-leaf stage were exposed to 25, 50 and 100 Gy of γ rays from a 60Co source. The growth parameters, chlorophyll contents, photosynthetic gas exchange, chlorophyll fluorescence, malondialdehyde (MDA) content, antioxidant enzyme activities and antioxidant contents were examined at 1–5 weeks post-irradiation (WPI). The results showed that plant height, leaf number and tiller (branch close to ground) number were significantly suppressed by 50 and 100 Gy irradiation at 5, 3–5 and 4–5 WPI, respectively, but they were not significantly different from control by 25 Gy irradiation. Chlorophyll a, chlorophyll b, and total chlorophyll contents were also found to be significantly decreased by irradiation. The net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr) generally declined in a dose-dependent manner. As for the chlorophyll fluorescence parameters, maximum quantum efficiency of PSII photochemistry (Fv/Fm), actual photochemical efficiency of PSII (ΦPSII) and photochemical quenching (qP) were observed to be significantly decreased compared to the control at 3 WPI, while non-photochemical quenching (NPQ) significantly increased by 100 Gy. γ-irradiation induced substantial increase in MDA content, ascorbate peroxidase (APX) activity, reduced ascorbate (AsA) content and reduced glutathione (GSH) content, suggesting a protective mechanism of Z. latifolia plant against oxidative stress when exposed to γ-irradiation. - Highlights: • The responses of Zizania latifolia plants to 60Co γ-irradiation were examined. • Plant growth was suppressed by high doses of irradiation but slightly affected by low doses. • γ-irradiation reduced PSII activity and chlorophyll content. • γ-irradiation

  7. Effects of total base of sophora alopecuroides on lipid peroxidation of 60Co γ-rays irradiated mice

    Objective: To study the effects of total base of Sophora alopecuroides on lipid peroxidation of irradiated mice. Methods: The mice were treated orally with different doses of total base of Sophora alopecuroides, after exposed to whole-body 60Co γ-rays at a dose of 5.0 Gy. The content of MDA in the liver and activities of Se-GSH-PX, SOD, GPT, GOT were measured. Results: After irradiation, the general status of the mice were changed such as hair deprivation, body weight reduction, blood spots appeared on the tail. Activities of Se-GSH-PX, SOD decreased remarkably, whereas those of GPT and GOT increased. MDA contents increased obviously. Oral administration of total base of Sophora alopecuroides could accelerate restoration of these indexes. Conclusion: Total base of Sophora alopecuroides has certain protective effects on irradiated mice, the mechanism of which may be related with antioxidation

  8. The sensitivity of the most common microorganisms of pig liquid manure to the effect of 60Co irradiation

    In model experiments the most common representatives of pathogens and facultative pathogens of pig liquid manure contaminating bacterial flora were examined for their sensitivity to different doses of 60Co, using liquid medium supplemented with 1% glucose, as well as Korthof-medium and different kinds of selective media. Erysipelothrix rhusiopathiea, Brucella suis, Mycoplasma hyorhinis and Pasteurella haemolytica proved to be the most senstive ones to irradiation, as they did not survive 100 krad dose. The highest resistances were observed in the cases of the following microorganisms: the spore containing Bacillus anthracis, killed by 700 krad irradiation dose, the saprophytic and pathogenic Mycobacteria and the spore containing Clostridium perfringens, killed by 1000-1500 krad irradiation. (author)

  9. A case of AML with preceding hypoplastic stage after oophoro-hysterectomy and 60Co-irradiation

    A case of AML (preceded by a hypoplastic stage) which developed after oophoro-hysterectomy and 60Co-irradiation is presented, and related literature concerning irradiation-induced leukemia and the early diagnosis of leukemia and/or preleukemia are discussed. The patient, a 47 year old female had had surgery and irradiation with a subsequent normachromic anemia necessitating transfusions 11 years prior to her presenting herself at our hospital because of anemia. Her pancytopenic peripheral blood picture combined with a relatively hypererythroid marron led to a diagnosis of atypical hypoplastic anemia. Two years after this she suddenly developed a high fever, general fatigue and a severe anemia. Hematological studies revealed acute myeloblastic leukemia. A combination therapy consisting of DM, 6MP, prednisolon and blood transfusions was given with no effect and 3 months after the onset, the patient died of asphyxia resulting from gross hemoptysis. Autopsy revealed pulmonary hemorrhage secondary to the leukemia. (J. Evans)

  10. Study on influences of rabbit thyroids irradiated by 60Co-gamma ray

    Effects of radiotherapy on the thyroid gland were evaluated with rabbits. gamma ray of 3.000R was irradiated locally. Thyroid hormone T4 and T3 were assayed by RIA method, blood flow was estimated by sup(99m)Tc-MAA uptake, and histopathological changes were also studied. T4 and T3 markedly decreased one day after irradiation, and a decrease of T4 was greater than that of T3. T4 and T3 continued to decrease until 3 days after irradiation, then, began to increase slowly, 7 days after irradiation, and almost returned to the initial level 14 days after irradiation. T4 kept the level thereafter with little changes, but T3 tended to decrease. sup(99m)Tc uptake decreased sharply one day after irradiation and continued to decrease gradually. It began to increase slowly 28 days after and almost returned to about 2/3 the initial level 56 days after irradiation. Histopathological study revealed no remarkable changes except degeneration and proliferation of follicular epithelium 14 days after irradiation. Changes in T4 and T3 due to decreased thyroid function after irradiation was comparatively parallel to histopathological changes. However, changes in blood flow and those in T4 and T3 were parallel with each other only at the time immediately after irradiation and at the end of the follow-up. This tendency was marked in T4. (Ueda, J.)

  11. The variation of short-branch type pear induced by 60Co γ-ray irradiation

    The variation of short-branch type Apple pear and Korean pear(Pyrus communis) induced by γ-ray irradiation was discussed. The results obtained are as follows: In comparing with Apple pear, Korean pear appeared more susceptible to γ-ray treatment; γ-ray irradiation increased the frequency of the short-branch variation; The character of short-branch induced by γ-ray irradiation could be directly introduced to the V(vegetative) generation

  12. Influence of 60Co-γ ray and electron beam irradiation on physicochemical characteristic of pork

    The effects of γ ray and electron-beam irradiation on the physicochemical characteristic of chilled pork were investigated to determine the appropriate irradiation mode. Pork was soaked in antioxidant solution (1 g/L), packaged in vacuum, irradiated at 3 kGy, and refrigerated storage for 30 d. Total bacterial counts, peroxide values, thiobarbituric acid reactive substances, volatiles and off-odor of irradiated pork were analyzed. Total bacterial counts of irradiated pork reduced and were <10 cfu/g at 30 d. Peroxide values, thiobarbituric acid reactive substances and volatiles contents of pork irradiated by y ray were higher than pork irradiated by electron-beam Pork irradiated by γ ray combined with antioxidant was most close to nonirradiated pork in odor, and similarity was 89.68%. Results showed that electron-beam irradiation reduced lipid oxidation and volatiles contents, and γ ray helped to reduce off-odor, furthermore, addition of antioxidant could effectively reduce lipid oxidation and off-odor. (authors)

  13. 60Co γ-irradiation mutation induction for screening of avilamycin strains with high productivity and its culture medium optimization

    60Co γ-irradiation was used for mutation treatment to screen high avilamycin production strains. Irradiation at 350 Gy gave a positive mutation ratio at 26.5%. The derived mutant H-15 strain of Streptomyces viridoehrongenes showed high avilamycin productivity at 68.5mg/L. Then effects of different carbon and nitrogen sources on the producing strain H-15 were investigated by one factor test and optimized with Response Surface Methodology. The results indicated that the optimum carbon and nitrogen source were soluble starch 20.12g/L, ribose 7.81 g/L, soy powder 25.23 g/L and soy peptone 5.06 g/L. Under those conditions, the predicted consistent value of avilamycins yield was 101.48 mg/L, which was in consistent with the measured value. (authors)

  14. 60Co irradiation effects on cooked rice texture and amylopectin structure

    The effect of γ irradiation on the cooked rice texture and amylopectin structure is studied with three varieties (Zhefu 504, Zhefu 802 and Zaogeng T2) subjected to 4 kGy, 8 kGy and 12 kGy irradiation. The results indicate that irradiation has significant effect on the texture of the cooked rice; the hardness, cohesiveness, gumminess and chewiness reduce significantly with the increase of the irradiation dose. Irradiation also affects the chain length distribution of the amylopectin, the side-chains of amylopectin of Zhefu 504 with the 12 ≥ DP, Zhefu 802 with 24 ≥ DP ≥ 13 and Zaogeng T2 with 24 ≥ DP ≥13 and 36 ≥ DP ≥ 25 are broken

  15. Influence of 60Co γ irradiation pre-treatment on characteristics of hot air drying sweet potato slices

    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 rose 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, 10 kGy, 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 170 min faster than that of 65 ℃. The drying speed of 7 mm sweet potato slices was 228 min faster than that of 3 mm sample. The cell wall and the vacuole of the sweet potato slices were broken after irradiation, and its water activity increased with the increase 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, 10 kGy, respectively. The hot air drying rate, surface temperature and water activity of sweet potato are significantly impacted by irradiation. The conclusion provides a theoretical foundation for further processing technology of combined radiation and hot air drying sweet potato. (authors)

  16. Underwater versus dry irradiation with {sup 60}Co, a qualitative analysis

    Omi, Nelson M.; Rela, Paulo R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: nminoru@ipen.br; prela@ipen.br

    2007-07-01

    The development of gemstone gamma irradiation devices showed that underwater irradiation leads to better results than the irradiation in dry condition. Many reasons may be shown for that behavior. This work intends to analyze qualitatively two of these reasons. The medium discontinuity between the irradiation source, gemstone, and the air inside the irradiation devices, which is minimized in underwater irradiation, is one of them. The other analyzed hypothesis is the differences between the interactions of source's direct radiation and those from the scattered radiation. The numerical study of these hypothesis, as long as some irradiation tests may be presented in future works. The main conclusion of this work is that the absorbed dose may have different behavior view if the depending on the kind and energy level of the absorbed dose. For example, it is not used to consider what portion of the dose is due to source's direct hit, what part is from ejected electrons with high or low energy and how much high, medium and low energy electro-magnetic quanta hit a portion of mass when determining its radiation dose. To know the total absorbed dose is usually, but not always, enough to explain a material response to radiation. (author)

  17. 60Co-γ-irradiation of dried DNA and isolated cell nuclei of chicken erythrocytes

    In this work low molecular products, which resulted from γ-irradiation of dried DNA, were isolated and quantitatively determined. Unchanged nucleic bases were released. The irradiation was successful in a vacuum as well as in oxygen. In the case of the drily irradiated DNA, the base release made up 30% of the total strand breaks. The release of DNA bases was also first studied in cell nuclei of eucaryotic cells, the erythrocyte nuclei of chicken blood. The second part of this work dealt with the isolation and identification of radiation induced changes in the 2-dioxyribose unit of DNA. In the third part it was investigated, whether as a result of γ-irradiation of DNA malonic dialdehyde was formed. It could be shown that neither malonic aldehyde nor basic propenal were formed, but instead products, which were still bound to the DNA and formed a chromophore with 2-thio barbituric acid. In this work the direct irradiation effect was investigated in DNA systems as well as in erythrocyte nuclei. By the isolation of low molecular irradiation products this work offers a contribution to the understanding of the irradiation chemistry in an eucaryotic cell, in which the direct effect on the DNA and the resulting radiation damage were given a deciding role for genetic information. (orig./MG)

  18. Cutaneous mitochondrial protection by topical treatment of herbal antioxodiants following 60 Co-gamma irradiation

    To find out the effective dose of herbal antioxidants to elevate the cutaneous lipid peroxidation (LP) at optimal level, gamma irradiation of cutaneous microsomal fraction was performed at different doses and 200 Gy was chosen. The present findings indicate that the failure of succinate in suppression of mitochondrial LP of irradiated rats might be due to diminishing of mitochondrial antioxidants which had been reduced by free radicals (generated by irradiation), since succinate suppressed mitochondrial LKP in antioxidant-treated rats. From these points of view, topical application of either curcumin or ellagic acid could be beneficial in prevention of radiation skin cancer

  19. Effect of 60Coirradiation on mating ability of males of Helicoverpa armigera

    The effects of γ-rays irradiation on the mating ability and flight capability of male cotton bollworm Helicoverpa armigera were studied in laboratory and field cages. The results showed that when the irradiation dose increased from 0Gy to 400Gy, the flight capability decreased: flight distance decreased from 69.65km to 38.30km; average flight distance decreased from 44.19km to 13.55km. The longevity of the irradiated males was significantly shorter than that of the wilds but there was no significant difference according to different doses. Egg hatchability was affected significantly by irradiation but there was no significant difference in eggs laid per female, fecundation eggs as increasing treated doses. When the ratio of sterilized males (treated dose 200 Gy) to fertile males was as 5:1 in field cages, the F1 hatchability was significantly decreased and the purpose of controlling cotton bollworm population could be effectively achieved. (authors)

  20. Effects of 60Coirradiation sterilization and influence on the quality of paprika powder

    The pollution of paprika powder was investigated and effects of gamma irradiation on the sterilization and quality were studied. The results showed that paprika powder was seriously polluted and gamma irradiation reduced significantly the total population of mesophilic bacteria, coliforms, lactobacillus, micrococcus, mould and spore. The mortality rate could reach 82%-94% at 2.62 kGy. There was no significant different between three kinds of packaging. The D10 va1ue of coliforms was 2.05-3.21 kGy, which were sensitive to irradiation and were the indicating bacteria of radiation dose setting. The lightness and yellowness of paprika powder decrease at high does, but total color difference and ASTA value had no significant difference, and the same to pungency by Scoville Test. So irradiation sterilization was perfect way to improve the quality paprika powder. (authors)

  1. Characteristic evaluation of papain irradiated with {sup 60}Co {gamma}-rays for the purpose of sterilization

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

    1998-09-01

    To establish irradiation sterilization method for hybrid biomedical materials containing bioactive molecules together with artificial polymers, we employed dry powder and aqueous solution of papain as a model and examined radiation tolerance with {sup 60}Co {gamma}-rays. The dry powder and frozen aqueous solution showed significant resistance after 30-kGy irradiation, indicating that commercial irradiation sterilization method for disposable medical supplies was applicable. Unfrozen aqueous solutions (10mg/ml), in contrast, showed significant drop of enzymatic activity within the early period of irradiation (ca. 0.5kGy) but 40% of the activity was recovered at ca. 3-kGy before total inactivation at 15kGy. Taking various conditions including dose rate, concentration of enzyme, oxygen and nitrogen bubbling into irradiation inactivation experiments, we demonstrated that inactivation of papain could be controlled under anoxic condition, such as nitrogen bubbling, increasing sample volume at high dose rates and high concentration of enzyme where dissolved oxygen was consumed rapidly. It is suggested that radiation inactivation of papain in the aqueous solution was occurred through reversible oxidation of the sulfhydryl group at the active site by free radicals derived from radiolysis of water and dissolved oxygen. (author)

  2. Comparison of the generation of interface states in MOS structures due to 60Co and VUV irradiation accompanied with photo-injection of electrons

    The buildup of interface states in MOS structures with differently annealed oxides is studied under vacuum ultraviolet (VUV) and 60Co irradiation. A larger creation of interface states is observed if photoinjection of electrons is applied simultaneously with the VUV irradiation. The presence of electrons at the Si/SiO2 interface favors the generation and explains the larger amount of interface states after 60Co irradiation. After VUV irradiation the interface state density increases in n-samples to a specific saturation value which is reached earlier if gate voltage is made more positive or samples are exposed to photoinjection. This is due to the increase of the radiation peak which is located in the upper half of the silicon gap. The impact of post oxidation annealing on the interface state generation is investigated due to VUV and 60Co irradiation. (author). 26 refs., 9 figs., 1 tab

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

    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

  4. Strand breaks and lethal damage in plasmid DNA subjected to 60CO-γirradiation

    Experiments with calf thymus DNA subjected to extracellular irradiation yield information on the role of direct and indirect effects in single-strand breakage, if this is evaluated with reference to the scavenger activity in respect of OH radicals. The role of the two processes in the occurrence of double-stand breaks and further damage leading to cell decay has so far remained largely obscure. It was the aim of the study described here to contribute to research in this field by performing in vitro experiments on biologically active DNA. For this purpose, DNA from pBR322 plasmids was irradiated in the presence of OH-radical scavengers. The number of single-strand and double-strand breaks was determined on the basis of the system's ability to eliminate OH radicals. In order to asses the influence of irradiation processes on the biological activity of DNA, investigations were carried out in E. coli for transformations caused by irradiated plasmid DNA. The results were interpreted in the light of theories about inhomogenous reaction kinetics put forward by Mark et al. (1989). It was finally discussed, which of the gamma-irradiation injuries occurring in DNA was to be held responsible for the inactivation of plasmid DNA and which enzymatic processes were additionally at work here. (orig./MG)

  5. Effect of the irradiation on Salmonella enteretidis var. typhimurium with gamma rays from 60Co

    The use of ionizinf radiation to the destruction of microrganisms responsible for food deterioration, and productive of feeding toxinfections constitute their usefulness for actually peaceful goals of nuclear energy. The feeding toxinfections are, among us, produced in their most part by Salmonella enteritidis var. typhimurim. One hundred nineteen samples of milk containing about 150.000 bacteria per ml, by means doses ranging from 100 to 1.100 gy, two samples of surviving bacteria were again irradiated by doses up to 2.5000 Gy. The bacteria not previously irradiated were throughly killed by means of doses of 1.100 Gy. Salmonella enteritidis var. typhimurium was inactivated by means of 1.200 and 1.900 Gy doses. It was concluded that 60-Cobalt gamma radiation minimal lethal dose to Salmonella enteritidis var. typhimurium is 1.200 Gy; the re-irradiation to the survivors prompts the forthcoming of more resistant germs. (author)

  6. Studies on acute toxicity and mutagenicity of 60Co irradiated pollens

    The acute toxicity test showed that the oral LD50 values were >21500 mg/kg for male and female mice, indicating that irradiated pollens belong to low toxicity grade or practically non-toxic. Mutagenicity were studied in three short-term tests. Ames test showed that irradiated pollens did not induce mutation towards strains TA99, TA97, TA100 and TA102. Micronucleus test in the bone marrow cells indicated that the percentage of polychromatic erythrocytes with micronuclei in exposed groups had no significant difference in comparison with the controlled ones. Chromosomal test for reproduction cells showed that the increase of chromosomal aberration rate was not observed. All the above results suggest that irradiated pollens are safe for human consumption

  7. Induction of mutation in Jujube (Zizyphus jujuba Mill) using tissue culture combined with 60Coγ-ray irradiation

    In vivo and in vitro mutagenesis techniques were assayed to explore effects of irradiation in jujube (Ziziphus jujuba Mill) improvement. 60Co γ-ray irradiated seeds and shoot tips of a land race of jujube originating in Shangdong province of China were micropropagated up to M1V4 generation on MS basal medium containing 2 mg/L BA and 0.4 mg/L IBA. The rooting MS medium contained 1 mg/L BA and 0.6 mg/L IAA, ZEA 1 mg/L, 2, 4-D 0.5 mg/L, and NAA 0.5 mg/L in different combinations. Adventitious buds were also produced from irradiated calli derived from leaf and hypocotyl fragments and the elongated adventitious buds rooted in vitro prior to green house transfer. Different doses (20 to 900Gy) were tested for in vitro explants as well as the jujube kernels irradiation. Six types of leaf shape and seven types of fruit shape mutations were observed and different ripening characters and growth habits were recorded in the orchard on putatively mutated mature trees. Even though there is a need for confirmation and molecular characterization, these mutations may be considered as a new and powerful way for jujube improvement in order to develop genotypes with promising value added traits. (author)

  8. 60Co γ-irradiation induced polymerization of methyl methacrylate in imidazolium ionic liquids

    Room temperature ionic liquids (RTILs), as a class of novel environmental benign 'green solvents', have been used as reaction media for various polymerizations due to their unique properties of non-volatility, high polarity, ease of recycling and chirality. In radiation polymerization, the energetic photons or electrons result in the formation of solvated electron and radical ions in ionic liquids, which initiate polymerization of monomers without any chemical initiator. In this work, effects of gamma ray irradiation on pure ionic liquid [bmim][PF6] was investigated in detail in a dose range of 5-400 kGy. The ionic liquids were quite stable under low dose irradiations, but underwent notable radiolysis with high doses. With the irradiated [bmim][PF6], the UV-Vis absorbance increased and the fluorescence intensity decreased with increasing doses. Raman spectra proved that gamma radiation induced significant chemical scission of n-butyl group (e.g. C-H and C-C scission), along with damages to the [PF6]- anion. In cooled samples of the irradiated [bmim][PF6] we found two coexist crystal structures, which had suffered a continuous destruction under high dose irradiation. After ensuring stability of the ionic liquids to low dose irradiation, radiation polymerization of methyl methacrylate (MMA) in ionic liquids and IL/organic solutions was performed. By adding the ionic liquids, the monomer conversion and molecular weight (Mw) of the polymer increased significant. Mw of PMMA in neat ionic liquid increased by about 60 times, from 3 x 104 with pure organic solvent to about 2 x 106. Molecular weight of the polymer increased with the IL fraction in the IL/organic solutions, and it was dependent on ionic liquids and solvents used, too. It was also found that the polymer obtained in the existence of IL showed multi-modal broadened molecular weight distribution (MWD). A reasonable explanation is the inhomogeneous nature of the ionic liquid in micron scale and the complicated

  9. Studies on the use of 60Co irradiation to control infectivity of Toxoplasma gondii

    Toxoplasma gondii cysts in minced pig brain, tongue, liver, heart and muscle were placed into plastic vials. These materials were irradiated at various doses. The irradiated tissue was then treated with artificial digestive juice and the suspension of bradyzoites prepared. The suspension was used to infect mice intraperitoneally and kittens orally. Unirradiated tissue with T. gondii was given to mice and kittens to serve as controls. Determination of infectivity was done on the 50th day after the mice were infected or 3-15 days after the kittens were infected. Loss of infectivity was confirmed according to the following criteria: no cyst in mouse brain impression smears; no oocyst in faeces of kittens; subinoculation in mice and indirect haemagglutination tests were negative, while all bioassay, parasitological examinations and serological tests in the control group were positive. Repeated experiments were done in order to calculate the minimal effective irradiation dose (MED). Activity of radiation source: 37 x 1013 bq; uniform dosage: 12.38 Gy/min. Results showed that (1) the MED of gammar rays to control infectivity of the Chinese NT strain and the US ME-49 and TS-2 strains of T. gondii cysts in pork was approximately 0.6 kGy; and (2) infectivity for mice of NT strain bradyzoites released from cysts irradiated with gamma rays at a dose of 0.45 kGy decreases to 1/10,000. These data could be valuable in practical operations to control T. gondii in pork products. (author). 7 refs, 1 fig., 4 tabs

  10. Fire Events Effect on Concrete Shielding of 60Co Industrial Irradiation Facilities

    Concrete is the most important structural which is used in radiation shielding for owing to its low price and good shielding performance. In concrete structures, of industrial irradiation facilities cracks occur due to thermal stress, hydration he at, weather, dry storage radiation of sources and fire events nuclear reaction. Shielding performance is effected according to the crack size geometry (width, depth and bending). However, there are no design criteria providing the allowable crack size limits for concrete shielding. Three different methods are applied in this work wbere the measuring instrument for qualifying the effect of cracks on shielding performance in concrete mass. The correlation between crack size and concrete shielding performance is deduced. The surface dose rate increased logarithmically according to the increase in crack width. The results are compared by the effects of fire events inside industrial irradiation facilities cold sterilization which led to change the effected mechanical parts and electrical components. Radiation concrete shielding is repaired. Radiation standard measurements outside irradiation concrete facility recorded normal radiation values. Radiation safety is maintained

  11. 60Co irradiation effect on color in minimally processed cauliflower (Brassica spp)

    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)

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

    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)

  13. Double strand breaks in DNA in vivo and in vitro after 60Co-γ-irradiation

    The questions of what the correlation is between double strand breaks in DNA in the cell and lethal radiation damage and by means of which possible mechanisms DNA double strand breaks could occur were studied. E. coli served as test system. In addition to this the molecular weight of the DNA from irradiated E. coli as a function of the radiation dose under various conditions was measured. This data was compared on the one hand to the survival of the cell and on the other hand to the formation of DNA double strand breaks in an aqueous buffer system, which in its ionic characteristics was similar to cell fluids. (orig./MG)

  14. The Effect of 60Co Gamma Irradiation on Various Fractions of Human Blood-Plasma Proteins

    The potential usefulness of employing ionizing radiation to cold-sterilize biomedical products has stimulated interest in characterizing the radiation sensitivity of various biologicals like vitamins, antibiotics, enzymes, antibodies and blood plasma fractions. This report presents findings on the sensitivity of haemagglutinin activity in human sera exposed to cobalt-60 gamma radiation. At doses tested between 0.2 and 5.0 Mrad, α-isohaemagglutinins were found to be more readily inactivated than ß-isohaemagglutinins, but neither was completely inactivated in this range. Sterility, clotting and antihaemophilic activity were also assessed on irradiated and freeze-dried preparations of human plasma with no significant differences in response detected. (author)

  15. The use of 60Co-γ-irradiation for the production of vaccines

    The polymerization conditions for the incorporation of virus antigens into poly(methyl methacrylate) particles were investigated. The dose and the dose rate appeared to be the relevant factors for optimizing the polymerization conditions. It was concluded that a dose of 500 krads at a dose rate of 2.2 krads min-1 leads to a satisfactory product. With these irradiation conditions the antibody inducing properties of fluid influenza and polio vaccines were not affected. Influenza virions incorporated into poly(methyl methacrylate) particles exhibited strong adjuvant properties during revaccination. (author)

  16. Storage pool water condition of multipurpose compact 60Co irradiator of IPEN-CNEN/SP

    A new type compact gamma irradiator was developed and installed at IPEN-CNEN/SP, it is classified as category IV irradiator according to International Atomic Energy Agency-IAEA. The originality of its design remains on the rotating concrete door, which integrates the shielding system with the product handling system, permitting the input and output of the products in a continuous way, without the necessity to lower the sources and open the irradiator chamber to change the batch. The licensed capacity of this irradiator is 37 P Bq (1 MCi) and the water pool liner, manufactured in stainless steel, has 7.0 m deep and 2.7 m diameter. A sealed radiation source may be defined as a quantity of radioactive material sealed within non-radioactive material, which the confining barrier is intended to prevent leakage or escape of the radioactive material under normal handling conditions and also under foreseeable mishaps. The use of cobalt-60 radiation sources in a wet storage environment requires care in the control of that environment to avoid the potential for deterioration of the stainless steel. In the literature, the tests performed demonstrated that stainless steel had excellent performance under controlled environment conditions. The inspection includes assessing the condition of storage pool water and measuring the pool water conductivity. The demineralized water normally used in storage pools is usually an effective and secure medium in which to store stainless steel. However, there are certain constituents and contaminants in the water which can affect this behaviour. For instance, the pH has a small but definite effect on the tendency for pitting corrosion. Nevertheless, there is also evidence that both strongly alkaline and strongly acid environments can encourage pitting corrosion. In general, an around neutral pH is recommended. The conductivity is used as a measure of the extent to which ionic species are present in the pool water. International recommendations

  17. A comparison of 95 MeV oxygen ions and 60Co gamma irradiation effect on nonlinear optical L-alanine cadmium chloride single crystals

    Single crystal of nonlinear optical (NLO) material L-alanine cadmium chloride (LACC) was grown by slow evaporation method at room temperature. The grown crystals were irradiated with 95 MeV oxygen ions and 60Co gamma radiation at doses of 1 Mrad and 6 Mrad. The structural, chemical, dielectric properties, AC and DC conductivity, refractive index of the crystals were studied before and after irradiation. There is a slight change in the lattice parameters due to compressive strain field generated in the irradiated crystals. The observed increase in dielectric constant was found to be more for 60Co gamma irradiated crystals than 95 MeV oxygen ion irradiated crystal. A considerable change in the values of refractive indices was observed for both gamma and ion irradiated crystals. The AC and DC conductivity was found to increase after irradiation. (author)

  18. Calibration of radioprotection instruments and calibrated irradiation: characterization of gamma beam of 137Cs and 60Co

    Radioprotection Laboratory belongs to Dosimetry Reference Regional Centre of Atomic Energy National Commission, C.A.E. This laboratory offers the service of calibrations for radioprotection instruments as Geiger Muller detector, ionisation chamber, probe, proportional counters, electronic personal dosimeters and others used in nuclear medicine, radiotherapy centres, nuclear power plants, industry and in other applications of ionising radiation. Also it offers the service of calibrated irradiations. A gamma Irradiator and a Stabilipam 300 X-ray are the equipment of the Radioprotection Laboratory used for calibrations. Hopewell Designs Irradiator was installed to improve the quality of services in 2005. The irradiator has a 137Cs source of 10 Curies and a 60Co source of 1 Curie, approximately. Theoretical and experimental studies were done to analyse symmetry, flatness, penumbra and secondary radiation of photon beams. For symmetry, flatness and penumbra X-OMAT-V films and thermoluminescent dosimeters (TLDs) were used. Films were placed to 0.7 and 1 meter from collimator exit receiving 10, 40, 80, 100 and 120mGy. TLDs were placed to 1 and 1.80 meters from collimator on a surface higher than 137Cs beam cross section. Also studies were done to a distance of 1m and 1.80 from exit collimator using LiF powder in capsules. Irradiations were done without attenuators and with a collimator aperture of 8 C degrees. Results were compared to those obtained with Monte Carlo simulation (MCNP5c code). For secondary radiation calculation three methods were employed: Shadow-shield, Multiple distance and Monte Carlo simulation. Finally, from theoretical and experimental studies could conclude that the secondary radiation resulted to be lower than 3.5%, total radiation, symmetry and flatness were higher than 90% and penumbra was lower than 13 mm. Those results agree to recommendations ISO 4037 Standard. (author)

  19. A comparison of large-scale electron beam and bench-scale 60Co irradiations of simulated aqueous waste streams

    The effectiveness of using high energy electron beam irradiation for the removal of toxic organic chemicals from water and wastewater has been demonstrated by commercial-scale experiments conducted at the Electron Beam Research Facility (EBRF) located in Miami, Florida and elsewhere. The EBRF treats various waste and water streams up to 450 l min-1 (120 gal min-1) with doses up to 8 kilogray (kGy). Many experiments have been conducted by injecting toxic organic compounds into various plant feed streams and measuring the concentrations of compound(s) before and after exposure to the electron beam at various doses. Extensive experimentation has also been performed by dissolving selected chemicals in 22,700 l (6000 gal) tank trucks of potable water to simulate contaminated groundwater, and pumping the resulting solutions through the electron beam. These large-scale experiments, although necessary to demonstrate the commercial viability of the process, require a great deal of time and effort. This paper compares the results of large-scale electron beam irradiations to those obtained from bench-scale irradiations using gamma rays generated by a 60Co source. Dose constants from exponential contaminant removal models are found to depend on the source of radiation and initial contaminant concentration. Possible reasons for observed differences such as a dose rate effect are discussed. Models for estimating electron beam dose constants from bench-scale gamma experiments are presented. Data used to compare the removal of organic compounds using gamma irradiation and electron beam irradiation are taken from the literature and a series of experiments designed to examine the effects of pH, the presence of turbidity, and initial concentration on the removal of various organic compounds (benzene, toluene, phenol, PCE, TCE and chloroform) from simulated groundwater

  20. A comparison of large-scale electron beam and bench-scale 60Co irradiations of simulated aqueous waste streams

    Kurucz, Charles N.; Waite, Thomas D.; Otaño, Suzana E.; Cooper, William J.; Nickelsen, Michael G.

    2002-11-01

    The effectiveness of using high energy electron beam irradiation for the removal of toxic organic chemicals from water and wastewater has been demonstrated by commercial-scale experiments conducted at the Electron Beam Research Facility (EBRF) located in Miami, Florida and elsewhere. The EBRF treats various waste and water streams up to 450 l min -1 (120 gal min -1) with doses up to 8 kilogray (kGy). Many experiments have been conducted by injecting toxic organic compounds into various plant feed streams and measuring the concentrations of compound(s) before and after exposure to the electron beam at various doses. Extensive experimentation has also been performed by dissolving selected chemicals in 22,700 l (6000 gal) tank trucks of potable water to simulate contaminated groundwater, and pumping the resulting solutions through the electron beam. These large-scale experiments, although necessary to demonstrate the commercial viability of the process, require a great deal of time and effort. This paper compares the results of large-scale electron beam irradiations to those obtained from bench-scale irradiations using gamma rays generated by a 60Co source. Dose constants from exponential contaminant removal models are found to depend on the source of radiation and initial contaminant concentration. Possible reasons for observed differences such as a dose rate effect are discussed. Models for estimating electron beam dose constants from bench-scale gamma experiments are presented. Data used to compare the removal of organic compounds using gamma irradiation and electron beam irradiation are taken from the literature and a series of experiments designed to examine the effects of pH, the presence of turbidity, and initial concentration on the removal of various organic compounds (benzene, toluene, phenol, PCE, TCE and chloroform) from simulated groundwater.

  1. 255Gy irradiated tachyzoites of Toxoplasma gondii induce intestinal immune response in C57BL/6J immunized by oral route

    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 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. 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)

  2. High dose rate 60Co remote afterloading irradiation in cancer of the cervix in Haiti, 1977-1984

    From 1977 through 1984, 293 previously untreated patients with biopsy proven carcinoma of the uterine cervix were treated by whole pelvis irradiation and high intensity 60Co remote afterloading (RAL) intrauterine tandem techniques in Haiti. The treatment results were analyzed retrospectively to evaluate the therapeutic results and prognostic factors of a strict protocol involving 40 Gy to the whole pelvis (2 Gy/day, 5 days/week). In addition, on the 5th day of the 3rd week, the first outpatient 60Co remote afterloading intracavitary insertion, delivering 7.5 Gy to point A with each insertion, repeated 3 times by a week separation for a total of 4 times. The total TDF for external beam plus RAL was 158 and 175 for early and late effects respectively. One hundred-four patients were evaluable after 1 year or more follow-up, with a median of 26.5 months. No evidence of disease (NED) by Stage at 1 year was: Stage I of 100% (3/3), Stage II of 82% (9/11), Stage III of 80% (47/59), and Stage IV of 58% (18/31). The post-therapeutic complication rate was 7.7%, with no fistulas or requirement of surgical intervention. Those with documented follow-up of at least 2 years (74 patients) had comparable survival to other high dose rate and low dose rate studies. This study shows that outpatient brachytherapy can be carried out without sophisticated and expensive equipment with minimal staff trained in radiation therapy. A detailed description of this outpatient RAL technique and results are described so that this method can be adapted to other developing and industrialized nations where cost containment is becoming a key issue

  3. Induction by gamma irradiation (60Co), characterization and utilization of mutants for economic traits in Isabgol (Plantago ovata Forsk.)

    Plantago ovata (Isabgol) is an annual herb which attains a height of 30-40 cm. The stem is wholly underground and covered with fine hairs. It is important for its seeds and husk which have been used as laxative for centuries all over the world. Induced mutation breeding was initiated for augmenting the spectrum of variability as also to select a genotype adaptable to north Indian conditions. Dry seeds of P. ovata (three generations selfed) were irradiated with gamma rays (60Co, 10-100 kR) at the interval of 10 kR and treated with the chemical mutagen, ethidium bromide (EB-0.2%). Mutagenesis resulted in useful qualitative and quantitative variations and changed the mean values for different agronomical traits in both positive and negative directions. A wide range of viable morphological mutants was isolated and the spectrum of viable mutations was wider. Pollen fertility declined in various directions with increased doses of gamma rays as compared to control. Irradiation at more than 50 kR doses reduced seed germination. LD50 was found to be between 40-50 kR doses. Earlier a promising mutant was released as a variety Niharika and now another mutant FEA-5 is in pipeline for release for commercial cultivation in North Indian plains. (author)

  4. Influence of natural antioxidants on lipid composition of beef burgers submitted to irradiation in 60 Co source and electron beams

    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 60Co 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)

  5. Day-and-night rhythm change in the contents of 5-hydroxytryptamine (5-HT) of brains and livers of mice irradiated by 5Gy 60Co γ rays

    The day-and-night rhythm changes in the contents of 5-HT of the brains and livers of mice treated by whole-body irradiation with 5 Gy 60Co γ rays were investigated by means of fluorescent spectrophotometry. The results showed that compared with control, the 5-HT contents in both tissues, generally speaking, were increased significantly after diurnal irradiation, but decreased insignificantly after night irradiation

  6. Effect of low dose irradiation of 60Co γ-rays on seed germination, seedling growth and enzymes activity of Lactuca sativa

    The seeds of Lactuca sativa were irradiated by different doses (10, 20, 30, 40, 50 Gy) of 60Co γ-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 30 Gy. POD activity after irradiation treatment in the range of 10 to 50 Gy and CAT activity after irradiation treatment in the range of 20 Gy to 40 Gy was lower than that of control. (authors)

  7. Some Results Of Gamma-60Co Irradiation Application To Breed New Soybean Varieties At Institute Of Agricultural Genetics, 2001 - 2007

    To overcome the disadvantage characters and continue create new genetical materials in new Soybean variety selection to get high yield, resistance to with disadvantage conditions, good quality. The Institute of Agricultural Genetics successfully combinated the good particularities of mutant varieties DT84/DT83 and received DT2001 variety, and from mutant DT90/DT84 received new variety DT96. These varieties quite resists with rare good drought-tolerant, high yield from 2000 to 3500 kg/ha, appropriate with all of 3 crops: spring, summer and winter and have wide adaptation. DT96, DT2001 varieties were adopted by MARD Scientific Council as New National Varieties. cooperated with Dalat Institute of Nuclear research treated the Gamma - 60Co Irradiation on Soybean and Vegetable Soybean. Irradiated dry seed of 3 varieties DT96, DT2001, DT158 with dose levels of 150, 200, 250 Gy in order to shorten the rise time and strengthen the drought resistance. At M3 generation had selected 3 lines D.96/26, D.01/58, D.58/08, D.58/224, which have rise time from 3 to 5 day shorter and yield higher than control (D.96/150, D.01/245). Irradiated the 2 vegetable Soybean DT02 (to ameliorate its thick shell, improve sweetness and resist with collapse) and DT06 (to ameliorate its heat resistance) with dose levels of 100, 140, 180, 220 Gy were received the generations and now continue being researching the M3 generation in 2007 summer crop. (author)

  8. Comparative studies on chromosome aberrations in rhesus monkeys induced by 60Co γ ray irradiation under different irradiation conditions

    Rhesus monkeys were irradiated by 60Cr γ ray exposure under different conditions, and comparative studies on their chromosome aberrations have been made. The dose rate of single acute irradiation was 223 mGy/min, the dose rate of fractionated curmulative irradiation was 223 mGy/min, and the dose of 0.25 Gy was delivered once a week, the dose rate of chronic continuous irradiation was 0.26 mGy/min for 190 min, 5 days per week. The total coumulative dose for each group was 2.0 Gy. It was found that the types of chromosome aberrations were mainly dicentric aberrations and acentric fragments in single acute irradiation, and acentric fragments in both fractionated coumulative and chronic continuous irradiation groups. The frequencies of chromosome aberrations in these groups increase linearly with increasing dose. The degree of chromosome damage in single acute irradiation group was much greater than those in the other groups, but degree and characteristics of chromosome damage between fractionated cumulative and chronic continuous irradiation groups was not significantly different. Acentric fragments in lymphocyte chromosomes ceased to increase when the cumulated dose in fractionated cumulative or chronic continuous irradiation reached to more than 1.0 Gy. The frequencies of chromosome aberrations basically decreased to control level within a year following the termination of irradiation

  9. 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

    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)

  10. Differential expression profiles of microRNAs in liver of 60Co γ-ray irradiated mice

    Objective: To investigate the differential expression profiles of microRNAs in the liver of 60Co γ-ray irradiated mice using microRNA microarray and to explore their main functions by bioinformatic analysis. Methods: After SPF C57BL/6J mice expose to 4 Gy-single whole body radiation,total number of peripheral WBC and the fMNPCE were measured at 3 d.The differentially expressed miRNAs in mouse liver were detected with miRNA microarray, miRNA-124 and miR-34a were confirmed by real time RT-PCR assay. Bioinformatic analysis was applied to explore target genes and the main functions of the differential expressed miRNAs. Results: Compared with control group, the total number of peripheral WBC decreased (t=2.87, P<0.05), while the fMNPCE in bone marrow increased (t=-2.91, P<0.05) after 4 Gy γ-ray irradiation.miRNA microarray revealed that 17 miRNAs were differentially expressed, in which 9 up-regulated, 8 down-regulated. The expression levels of miR-124 and miR-34a were coincident with the result of real time RT-PCR. GO analysis showed that some pathways including adherens junction and cell cycle were suppressed, while some immune-related pathways were activated. Conclusions: miR-34a and miR-194 were involved in the regulation of acute radiation damage, some other miRNAs including miR-124, miR-382 and miR-92a* also played important roles in radiation process. (authors)

  11. Obtained and evaluation of antisera raised against irradiated crotalic whole venom or crotoxin in 60 Co source

    Snake bite is a great Public Health problem in our country. The accidents with snakes from Crotalus genus are the most severe. About 1% of the victims die without seratherapy. The antivenons are obtained from hyper immune horse plasma. During the production these animals present signs of envenoming that result in a decrease of organic resistance besides the horses maintenance is very expensive and the producers are fewer, so the sera production is restrict. Many techniques which could reduce the venoms toxicity and increase the sera production using chemical and physical agents have been studied. The gamma rays are excellent tool to detoxify venoms and toxins. It is able to modify protein structures that decrease lethally, toxic and enzymatic activities without modifying the immunogenicity. So, it is important evaluate the sera production in rabbits using gamma rays detoxified venom and crotoxin as immunogen and their power as reagents in immuno assays. In order to obtain the antisera, Crotalus durissus terrificus whole venom or isolated crotoxin was irradiated with 2.000 Gy in 60 Co source, in a 150 mM NaCl solution, and inoculated in rabbits. The sera production were screened by immunoprecipitation, immuno enzymatic (ELISA) and immunoradiometric (IRMA) assays. The specificity was studied by immuno-electrophoresis, ELISA and western blot techniques. The neutralizing power was evaluated by neutralization of phospholipase A2 activity of toxin in vitro. The antisera were used as reagents in antigen capture assays ELISA and IRMA immuno assays to detect circulant antigens in sera of mice experimentally inoculated with crotalic venom or crotoxin. The results showed that both detoxified venom or crotoxin were good immunogens, and they were able to induce antibodies that could recognize non-irradiated venom or isolated crotoxin. The data suggest that those antibodies present more specificity and higher in vitro neutralizing power, when compared with commercial

  12. 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

    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

  13. The effects of low-dose 60Co-γ rays irradiation on some enzyme activities and isoenzyme zymogram in pak-choi seedlings

    The changes in activities of ascorbate oxidase, polyphenol oxidase, catalase and zymogram of peroxidase isoenzyme, esterase isoenzyme in pak-choi seedlings induced by low-dose 60Co-γ rays irradiation were studied. The results indicated that the activities of ascorbate oxidase and polyphenol oxidase were enhanced. Zymogram of peroxidase isoenzyme and esterase isoenzyme also changed. And the effect of 6'0Co-γ ray on catalase was different. All these changes indicated the possibility of enhancing plant resistance, promoting growth and raising the yield of pak-choi

  14. 60Co-γ辐射对菊苣种子发芽及幼苗生理的影响%Effects of 60Co-γ-rays Irradiation on Chicory Seed Germination and Seedling Physiology

    张玉; 白史且; 李达旭; 王曾珍

    2013-01-01

    Chicory seeds were irradiated with 60Co-γ-rays at 100, 150, 200 and 300 Gy to determine germination rate and physiological characteristics from mutagenic effects of irradiation doses. Results showed that seed germination rate decreased as the irradiation dosage increased. There was significant difference between 200 Gy irradiation dosage and control(P<0. 05). Superoxide dismutase (SOD) activities, peroxi-dase (POD) activities, soluble protein and soluble sugar contents first increased then declined with a gradual irradiation increase, and differed significantly between control and 150 Gy, 100 Gy, 150 Gy, 150 Gy treatments (P<0. 05), respectively. MDA content increased with increased irradiation dosage, and there was significant difference between control and the treatments above 150 Gy dose (P<0. 05). The protein content first increased then declined, and differed significantly between control and treatments (P<0. 05). It was concluded that the mutagenic effect of chicory irradiated by low dosage (below 150 Gy) was not obvious. However, physiological and biochemical characteristics of chicory irradiated above 200 Gy were significantly altered. The study provides a theoretical basis for chicory radiation mutation breeding.%为明确60 Co-γ射线对菊苣(Cichorium intybus L.)辐照诱变效果,采用不同剂量60Co-γ射线(100 Gy,150 Gy,200 Gy和300 Gy)辐照处理菊苣种子,测定其发芽率和相关生理指标.结果表明:随着辐照剂量的增加,菊苣发芽率降低,200 Gy以上辐照处理发芽率与对照差异显著(P<0.05);超氧化物歧化酶(SOD)、过氧化物酶(POD)活性、可溶性蛋白和可溶性糖含量随着辐照剂量增加均表现为先升后降的趋势,分别在辐射剂量为150 Gy,100 Gy,150Gy,150 Gy及以上时与对照差异显著(P<0.05);丙二醛(MDA)含量随着辐照剂量增加而逐渐升高,150 Gy以上辐照处理与对照差异显著(P<0.05);蛋白含量呈现先增后减的趋

  15. The effects of seeds irradiation with 60Co γ-ray on seed germination and shoot growth of Brassica campetris L. ssp. Chinensis var. utilis

    Seeds of Brassica campetris L. ssp. Chinensis var. utilis pre-soaked with water for 1h were irradiated with 60Co γ-ray. Irradiation delayed the germination of seeds but did not affect the germination rate. The height, root length, fresh weight and survival rate of seedlings decreased with the increasing of irradiation dose. There were significant negative correlation between death rate and the height, root length and fresh weight. The dose of 200 - 300 Gy were recommended as suitable irradiation doses for pre-soaked seeds

  16. The effects of 60Co γ-ray irradiation on the DC characteristics of enhancement-mode AlGaN/GaN high-electron-mobility transistors

    Chen Chao; Tian Ben-Lang; Liu Xing-Zhao; Dai Li-Ping; Deng Xin-Wu; Chen Yuan-Fu

    2012-01-01

    The effects of 60Co y-ray irradiation on the DC characteristics of AlGaN/GaN enhancement-mode high-electronmobility transistors (E-mode HEMTs) are investigated.The results show that having been irradiated by 60Coγ-rays at a dose of 3 Mrad (Si),the E-mode HEMT reduces its saturation drain current and maximal transconductance by 6% and 5%,respectively,and significantly increases both forward and reverse gate currents,while its threshold voltage is affected only slightly.The obvious performance degradation of E-mode AlGaN/GaN HEMTs is consistent with the creation of electronegative surface state charges in the source-gate spacer and gate-drain spacer after being irradiated.

  17. 255Gy irradiated tachyzoites of Toxoplasma gondii induce intestinal immune response in C57BL/6J immunized by oral route

    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)

  18. 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

    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.

  19. The effect of combination of ErbB2 RNAi and 60Co γ-irradiation on U251 cell apoptosis

    To construct erythroblastic leukemia viral oncogene homolog 2 (ErbB2) small interference RNA (siRNA) expression vector and to study its effect on U251 cell line proliferation and apoptosis combining with 60Co γ-irradiation. ErbB2 specific 19bp oligonucleotides were designed and synthesized. These oligonucleotides were annealed to form the double strand DNA fragments, which was cloned into pSilence2.1-U6-H1 vector. The recombinant pSilence2.1-ErbB2 expression construct was confirmed by Hind III and BamH I double digestion and sequencing. The pSilence 2.1-ErbB2 was transfected into U251 cell. Cellular proliferation activities were assayed by tetrazolium bromide (MTT) colorimetry. The apoptosis of transfected U251 cell was examined with Hoechst 33258 staining and Annexin-V kit. Psilence 2.1-ErbB2 expression vector was successfully constructed and it can effectively inhibit pro- liferation(p60Co γ-irradiation, the effect of inhibiting proliferation was more significant compared with non-irradiated U251 cells(p60Co γ-irradiation can enhance the inhibitory efficiency in U251 cell line. (authors)

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

    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.

  1. Enhancing the lipid content of the diatom Nitzschia sp. by 60Coirradiation mutation and high-salinity domestication

    To improve the lipid accumulation of diatom cells, Nitzschia sp. was mutated by 60Co-γ-ray irradiation and cultivated with high salinity. The biomass and lipid yields of Nitzschia sp. mutated by 60Co-γ-ray irradiation at 900 Gy were increased by 53.8% and 28.1%, respectively. The lipid content of Nitzschia sp. mutant cells cultivated with gradually increased salinity of up to 30‰ was increased from 11.9% to 27.2%. This was because that the increased demand for nitrogen to keep cells healthy growth under high salinity conditions resulted in lipid accumulation, which was beneficial to prevent cell membranes from being destroyed by changing osmotic pressure. When the Nitzschia-ZJU1 strain obtained from Nitzschia sp. by irradiation mutation and salinity domestication was cultured in the growth media with no nitrogen and no silicon, the lipid content of cells was dramatically increased to 51.2%. - Highlights: • Nitzschia species were mutated by 60Coirradiation for high lipid production. • Mutants were domesticated with high salinity to increase lipid content in cells. • Lipid content of domesticated mutants was 1.3 times higher than original strain. • Lipid content reached 51.2% under 30‰ salinity, nitrogen and silicon deprivation

  2. Cytotoxicity evaluation of Diethyltoluamide (DEET) in Perna perna (Linnaeus, 1758) mussels non-irradiated and irradiated with 60Co gamma radiation

    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 60Co 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-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-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)

  3. The response to climate factors for the different specificity in M2 physiology of 60Co γ-ray irradiated flowers

    Physiology and climate factor of different M2 flower (Begonia tuberhybrida Voss and Dahlia pinnata Cav root) after 60Co γ-ray irradiated were determined. The result showed that transpiration rate, stoma conductance, intercellular CO2 concentration of M2 of Dahlia pinnata Cav are affected obviously with climate factors, however, effect on the photosynthetic speed was not found, and M2 of Begonia tuberhybrida Voss was not significant for physiology to climate

  4. The effects of chloramphenicol and 60Co irradiation on the experimental mycosis in mice inoculated intragastrically with two kinds of pathogenic yeast-like fungi

    Two kinds of pathogenic yeast, Cryptococcus neoformans and Candida albicans were inoculated into the stomachs of mice. The effects of intragastric administration of chloramphenicol (CM) and systemic irradiation with 60Co on the acceralation of infection were studied in intragastrically inoculated mice. When Cryptococcus neoformans were simply inoculated, it was difficult for them to reside in the alimentary canal to cause infection. In case of candida albicans inoculated simply, they were also unable to induce infection though they remained in the alimentary canal for a long time. In the experiment combining intragastric administration of the fungi and CM some mice contracted the disease and died. The effect of CM in causing infection was not proved. In the experiments combining 60Co irradiation and intragastric administration of CM and fungi, a high incidence of fungus infection was noted with both Cryptococcus neoformans and Candida albicans. Fungus lesions were observed in many organs, and in all of the mice which died systemic fungus lesions were noted. It was shown that systemic irradiation with 60Co had a specific effect on facilitating the infection. In these studies no difference was observed in the incidence of the fungus disease in respect of the origin of the causative fungi. (J.P.N.)

  5. Characterization of 60Co and 137Cs beams from irradiator Shepherd 81 - 14D of LNMRI/IRD in radiation protection

    The objective of this work is the characterization of 60Co beams and the 137Cs 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)

  6. Effect of 60Co γ irradiation with seed and shoot-tip of Brassica campestris L. var on its culture in vitro

    The survival rate in vitro of shoot-tips of Brassica campestris L. var from seeds irradiated by 60Co γ-rays decreased with the increase of dose. Irradiation inhibited proliferation of shoot-tip, induction of callus from cotyledons and differentiation of the callus. The age of explant contributed to the effect of irradiation in the culture. Irradiation stimulated the proliferation of shoot-tip with dose less than 50 Gy. Based on the effect of irradiation in the tissue culture, the effective dose recommended was about 200 Gy for seeds, 50-100 Gy for pre-soaked germinating seeds and 40-70 Gy for shoot-tips in vitro, respectively

  7. A primary study on mutation induction of in-vitro cultured garlic shoots by 60Co γ-ray irradiation

    In vitro cultured shoots of four garlic cultivars were used to estimate radio-sensitivities and mutation rate by 60Co γ-ray. LD50 of the tested materials was around 7∼9 Gy with a mutation rate of 5%. Two mutants, Tai-R1 and Cang R2 were proved to be genetical variants by the investigation on agronomic characters and the analysis of peroxidase isozyme

  8. Effect of hydrogen on change carrier dissipation in 60Co irradiated by γ-quanta and non-alloyed n-type GaAs

    The pretreatment in hydrogen plasma (the hydrogenation) influences on the charge carrier dissipation processes in the non-alloyed gallium arsenide of n-type with no = (5...7) centre dot 1015 cm-3 and μo = (5...6) centre dot 10 13 cm2 / (V centre dot c) irradiated by γ-quantum 60Co was studied. The comparison of experimental dependence μ (T) with the designed one in the temperature range 77...291 K for non-hydrogenized and hydrogenized non irradiated and γ-quantum irradiated crystals was carried out. It is shown that the main dissipative mechanism that determine the charged carrier mobility in the non hydrogenized material is the dissipation on the charged centers - the radiation defects in the γ-quantum irradiated GaAs; the presence of double ionized defects is possible

  9. Effect of 60Co γ-rays irradiation on growth and anti-oxidant enzyme activities of rhizomes in cymbidium goeringii

    The rhizomes of Cymbidium goeringii were cut into tip, middle and basal segments with a length of about 1 cm, and the segments were irradiated with 60Co γ-rays at doses of 0, 5, 10, 20, 30 and 50 Gy, respectively. The growth characters, the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (G-POD), and peroxidase isozyme of the were measured. The results showed that the segments irradiated at the dose of 30 and 50 Gy could survive, but couldn't form new rhizomes and the growth was almost stagnated. With the increase of the doses, the SOD and CAT activities of the rhizome were increased first, then significantly decreased, but the reverse effect was observed in G-POD activities, which was decreased first, then increased. Combining both the effect resuhson the growth characters, on activity changes of peroxidase isozyme and the changes of the anti-oxidant enzymes after irradiation, it was concluded that the appropriate doses of 60Co γ-rays irradiation for mutation breeding of Cymbidium goeringii should be in the rage of 20 to 30 Gy, and the optimal part of the rhizome seems to be the tip segment. (authors)

  10. Electrical characteristics of 60Co gamma-ray irradiated pentacene-based organic thin film field effect transistors

    Preliminary studies of the 60Co γ-ray radiation effects on pentacene-based organic thin film transistors (OTFTs) with two kinds of gate insulators have been carried out. Negative threshold voltage shifts of OTFTs with a SiO2 gate insulator are consistent with positive charge trapping, and a rebound effect is observed. Threshold voltage of OTFTs with a polyimide gate insulator continuously decreased with increasing the total dose. When the total dose reached 1200 Gy (Si), the carrier mobility of OTFTs with the SiO2 gate insulator decreased by nearly 80%, while the carrier mobility of OTFTs with the polyimide gate insulator decreased by almost 40%. (author)

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

    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.

  12. Effect of 60Co γ ray irradiation on electrical parameters of MOVPE grown GaAs epilayer and p-i-n detectors

    60Co γ ray irradiation on GaAs epilayer and p-i-n detectors structures was carried out to determine the radiation hardness of the devices. The carrier density and mobility decreases with increasing radiation doses due to the creation of Ga vacancies. The generation recombination centers increases with increasing radiation doses that leads to five fold increase in the dark current of the p-i-n device at 50 KGy. The radiation hardness value obtained was 4.7x10-19 A/cm. (author)

  13. Effect of fractionated 60Co γ-ray irradiation on 8-epi-prostaglandin F2α in plasma and RBC membrane of dogs

    Objective: By observing the alteration of 8-epi-prostaglandin F2α(8-epi-PGF2α) in plasma and RBC membrane of dogs during and after γ irradiation, and comparing it with malondialdehyde (MDA), the authors aimed to assess the value of measuring its concentrations in realizing the irradiation-induced lipid peroxidative reaction, and to detect the effect of superoxide dismutase (SOD) on this procedure. Methods: 18 adult out bred dogs (6 dogs each were randomly assigned to low-dose SOD treatment group, high-dose SOD treatment group and control group) were irradiated with 60Co γ-rays at a dose of 0.6 Gy per day for 5 days, and the concentrations of 8-epi-PGF2α and MDA in plasma and RBC membrane were assayed before, during, and after the irradiation. Results: The mean plasma 8-epi-PGF2α level in dogs was significantly increased during the γ-irradiation, and gradually decreased after the irradiation was ended, while the enhanced 8-epi-PGF2α concentration in RBC membrane was higher than that in plasma, and it reached the peak level at the 2nd day after the irradiation was ended and then started to decrease; SOD could markedly inhibit its increase. The levels of MDA in plasma and RBC membrane were not significantly changed. Conclusion: 8-epi-PGF2α can serve as a new and more sensitive index for reflecting the irradiation-induced lipid peroxidative reaction

  14. Destruction of Radiation-Resistant Micro-Organisms on Surgical Sutures by 60Co-Irradiation Under Manufacturing Conditions

    Any process adopted for producing sterile medical products must be demonstrated to produce sterility under reproducible manufacturing conditions. In addition, a margin of safety is required to guard against non-sterility due to undetected departures from standard operating practices. This study reports the results of exposure to 60Co γ-rays of surgical sutures intentionally contaminated with known radiation-resistant organisms, including St. faecalis, M. radiodurans and B. pumilus, under normal manufacturing conditions. Additionally, the results of over 20 000 sterility tests under prolonged incubation are reported to indicate that routine sterility testing of radiation-sterilized sutures is adequate to detect radiation survivors. The nature and level of the natural contaminants of surgical sutures before sterilization is tabulated and discussed from the standpoint of the safety factor inherent in the process. (author)

  15. Differential expression profile in the progeny of normal human liver cells irradiated by 60Co γ-rays

    Objective: To investigate the differential expression profile in the progeny of human liver cells surviving from ionizing radiation. Methods: Complemental DNA gene chip was used to measure the transcriptional profile in progeny of HL-7702 cells exposed to 0, 2, 4, and 6 Gy of 60Co γ-rays, and the differentially expressed genes HAVCR2 and RAN were further identified by real-time PCR. Results: The transcription level of 262 genes, 2746 genes and 3406 genes changed in the progeny of survival cells at 2, 4 and 6 Gy, respectively. A total of 71 common differentially expressed genes were screened, most of which were associated with transduction, cell cycle regulation, cellular immunity, cytoskeleton and movement, cell replication and repair mechanism. Conclusions: Ionizing radiation could induce the expression changes of many genes, which might reveal the molecular mechanisms of gene expression in radiation induced genomic instability. (authors)

  16. Dose-rate effect on chromosomal aberrations induced by 60Co γ-rays irradiation in human peripheral blood lymphocyte

    To estimate exactly the biological dose of persons exposed to different dose rate, human peripheral blood was exposed to 60Co γ-rays in vitro at low, middle and high dose rates respectively and chromosome samples were prepared, then dose-response curves were established according to the dicentrics and ring frequencies. The result showed that the aberration frequency at same dose level increased with dose rate and there was an obvious dose-rate effect. Absorbed dose estimated with low dose-rate dose-response curve was higher markedly than that with high dose-rate dose-response curve. So, considering the effect of dose-rate, approximate dose-rate dose-response curve should be chosen when absorbed dose estimation and the result will be credible. (authors)

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

    Zhao, Huiru; Gu, Yunhong; Ya, Huiyuan; Jiao, Zhen; Qin, Guangyong

    2009-02-01

    Mutagenesis and retrotransposons have a close relationship, but little attention has been paid yet to the activity of retrotransposons 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 5 × 10-2 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.

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

    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.

  19. Breeding of Xinchun No.30 with early maturity, good quality and high yield by hybridization and 60Co γ-rays irradiation

    F1 hybrid seeds of Xinchun 9/xinchun 6 were treated by 80 Gy 60Co γ-rays irradiation,after many generations' selection on single spike in progenies, Xinchun No.30 with early maturity, good quality and high yield was bred. Xinchun No.30 was officially registered by Xinjiang Crops Variety Examination and Approval Committee in March 2009. It was characterized by high and stable yield(5250-900 kg/hm2), wide adaptation area,good resistance to rust and powdery mildew, lodging resistance and medium to strong gluten quality. The results showed that hybridization combined with irradiation is a useful breeding approach to develop new varieties with drought resistance, good quality and high yield potential. (authors)

  20. Rapid rejoining of DNA strand breaks in resting human lymphocytes after irradiation by low doses of 60Co γ rays or 14.6-MeV neutrons

    The production and repair of DNA strand breaks was studied in human lymphocytes by means of a sensitive fluorometric technique. Lymphocytes were isolated by conventional methods and air-equilibrated suspensions were irradiated by low doses (less than or equal to 2 Gy) of either 60Co γ rays or 14.6-MeV neutrons at 00C. The apparent yield of initial strand breaks induced by neutrons was only 36% of that induced by γ rays, in agreement with the observations of other workers. Resting lymphocytes were found to be proficient in their ability to rejoin γ-induced strand breaks at 370C; rejoining followed biphasic kinetics, with 70% of the breaks disappearing with a half-life of about 3 min. Although the initial number of breaks induced by neutron irradiation was low, after 20 min of incubation the residual number of breaks was very similar for the two forms of radiation

  1. A study on the irradiation effect of 60Co-γ ray for dental P.M.M.A. bonded parts

    In this paper we describe an experimental study on the irradiation effect of 60Co-γ ray for dental P.M.M.A. welding parts, hot polymerizing adhesion parts and cold polymerizing adhesion parts. As a result of this series of test and experiments, it was found that from the result of tension test, no remarkable change is found with any of the bonded materials by the irradiation dose up to 107 r., and no deterioration by irradiation is observed. And then, according to the results of bending test, it is found that, although the three different bonded materials have different features, high strength of the welded material and of the material adhered by hot polymerizing adhesive becomes lower by irradiation, and strength of the three materials converges after irradiation within the range of 106-107 r. Joint efficiency of 65-75% in tension and 50-62% in bending can be adopted. With regard to fracture, blocks of each specimen are finely divided and show tendency of becoming brittle by irradiation. Fracture of the base material and of the bonded materials are similar and prove bonding of high strength. (author)

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

    The goals of this study were to examine the effects of 0, 50, and 100 rad of 60Co 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

  3. Effect of 60Co γ-irradiation on postharvest quality of pleurotus nebrodensis stored at 4 degree C

    The effect of γ-rays irradiation on the fresh-keeping of Pleurotus nebrodensis fruit bodies was reported in this paper. Fresh harvested fruit bodies of Pleurotus nebrodensis were irradiate at different doses levels (0.8-2.0 kGy) and stored for 22 days at 4 degree C. The fruit bodies treated with 1.2 kGy irradiation retained the highest soluble protein contents, and exhibited less postharvest softening throughout the storage period. Regression analysis plots of fruit body hardness versus soluble protein content were linear (t>0.05). Increases in mushroom cell permeability observed throughout the storage period were directly related to irradiation dose. Too higher dose(≥2.0 kGy) of irradiation will accelerate the nutrition degradation and rotting of the fruit bodies. (authors)

  4. Immune response against the irradiated Bothropstoxin-1 with 60Co: identification of main cytokines involved and the participation of scavengers substances

    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- IFNγ 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 (60Co 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-γ, 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-γ and IL-2 (Th1 response) than the control sample. The cells of Knockout-IFNγ 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. Experimental infection with Klebsiella pneumoniae and its gentamicin therapy in guinea pigs 60Co irradiated with 4 Gy

    Sublethal irradiation was used to suppress the immunity response of the organism. Following the development of infection with Klebsiella pneumoniae the therapeutical effect was compared of intramuscular administration and of inhalation of gentamicin. Intramuscular administration was statistically significant for reducing the mortality of infected guinea pigs as against non-treated animals at days 7 to 10 after irradiation. Administration by inhalation had the same effect between days 12 and 25 after irradiation. The weight and blood counts of the animals were observed during the experiment. (M.D.)

  6. The effects of 60Coirradiation on the cell proliferation kinetics of DMBA-induced tongue carcinoma in hamster

    In the occation 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 60Coirradiation to DMBA-induced hamster tongue carcinoma (hereafter ''the Tumor'') and normal tongue epithelium (hereafter ''the Normal'') by using 3H-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 (Tg1) of the Normal was 31.0 hours and that of the Tumor was 8.7 hours. After irradiation, Tg1 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. (author)

  7. The effects of 60Co γ-ray irradiation on the cytoskeleton of mouse peritoneal macrophages and human peripheral blood monocytes in vitro

    The whole mount cell electron microscopy in combination with selective extraction method for preparing cytoskeletal framework was applied. Cy toskeleton prepared by Triton X-100 treatment of mouse peritoneal macrophages and human peripheral blood monocytes appeared in electron microscopy as a highly organized and interconnected three-dimensional matrix of different fibrous elements. Since such cytoskeletons are open membrane-free system, individual fibrous organizations can be identified by specific antibodies. An indirect immunogold procedure using monoclonal anti-tubulin or anti-actin antibodies was applied to visualize tubulin-or actin-containing structures. The three-dimensional visualization of Triton X-100 resistant cytoskeletons had been used to demonstrate that different doses of 60Co γ-ray caused a distinctive and reproducible alterations of the cytoskeletons of intact mouse peritoneal macrophages and human peripheral blood monocytes in vitro. The results showed that there were some similar alterations with those caused by cytochalasin B and by colchicine. From these observations and other workers' studies, it's likely that 60Co γ-ray irradiation may inhibit cytoplasmic microtubule and microfilament assembling

  8. Performance of p-bulk microstrip sensors under 60Co γ irradiation at rates expected at the HL-LHC

    Takahashi, Y.; Hara, K.; Kim, S.; Ikegami, Y.; Takubo, Y.; Terada, S.; Unno, Y.; Mitsui, S.; Kamada, S.; Yamamura, K.

    2013-01-01

    We are developing p-bulk microstrip sensors for the high luminosity upgrade of the LHC accelerator, HL-LHC. The stability of FZ (float zone) wafers available to Hamamatsu Photonics was examined by irradiating them at rates expected at the HL-LHC. They show degradation in the operational voltage at low dose but recover after the dose is accumulated. The instability is dependent on the bias voltage and dose rate, and also on the irradiation history. We have characterized the instability and attributed the cause to the charge concentration at the electrode edge. The strip isolation, which is degraded while in irradiation, is shown not to induce any practical problem for the operation.

  9. Preparation and Characterization of Fe3O4 Magnetic Nano-particles by 60Co γ-ray Irradiation

    Mingcheng YANG; Hongyan SONG; Chengshen ZHU; Suqin HE; Ya GAO

    2007-01-01

    By using a new method, 60C0 γ-ray irradiation, Fe3O4 magnetic nano-particles were successfully synthesized at room temperature under ambient pressure. The structure, morphology and magnetic properties of these nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM), respectively. The radiation formation mechanism was also discussed. The results show that the absorbed dose can greatly influence the structure, morphology and magnetic properties of the products. XRD and TEM studies show that the product prepared by γ-ray irradiation (10 kGy) is pure FesO4 phase and the mean diameter of these nano-particles is about 21 nm. The Fe3O4 nano-particles synthesized by γ-ray irradiation (10 kGy) are mainly in small cubic shape and the size uniformity of these particles is good.

  10. Preliminary study on effects of 60Co γ-irradiation on video quality and the image de-noising methods

    There will be variable noises appear on images in video once the play device irradiated by γ-rays, so as to affect the image clarity. In order to eliminate the image noising, the affection mechanism of γ-irradiation on video-play device was studied in this paper and the methods to improve the image quality with both hardware and software were proposed by use of protection program and de-noising algorithm. The experimental results show that the scheme of video de-noising based on hardware and software can improve effectively the PSNR by 87.5 dB. (authors)

  11. Studies on progenitor cell compartments of 60Co irradiated and normal fetuses at 55 days of gestation

    Studies were performed on canine fetal tissues obtained from animals exposed to in vivo chronic irradiation and unexposed controls. CFU-GM, CFU-F and CFU-L assays were done using placental conditioned medium (PCM) or Concanavalin-A (Con-A) as the colony stimulating factor. Preliminary work using medium conditioned with canine spleen cells (SCM) was also begun which indicated that this colony stimulating factor greatly increases the number of colonies observed in both the CFU-GM and CFU-L assays. Chronic irradiation may adversely affect PCM responsive CFU-GM and CFU-F but not Con-A-reactive CFU-L

  12. Histologic effect of fractionated doses of selectively applied /sup 60/Co irradiation to the teeth of albino rats

    Sweeney, W.T.; Elzay, R.P.; Levitt, S.H.

    1977-01-01

    This study compares the effects of fractionated 2400, 4800 and 7200 rad doses of Co-60 irradiation on the formed and developing teeth of the rats. The 7200 rad dosage was found to cause damage to both odontoblasts and ameloblasts of developing incisors but to spare previously formed molars.

  13. Histologic effect of fractionated doses of selectively applied 60Co irradiation to the teeth of albino rats

    This study compares the effects of fractionated 2400, 4800 and 7200 rad doses of Co-60 irradiation on the formed and developing teeth of the rats. The 7200 rad dosage was found to cause damage to both odontoblasts and ameloblasts of developing incisors but to spare previously formed molars

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

    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)

  15. Comparison of the protective resistance induced by 60Co-irradiated cercariae and schistosomula of the WFFS and NMRI strains of Schistosoma mansoni

    Mice, CBA/HT6T6 and C57BL/10, were vaccinated with 1 x 350 or 1 x 500 Schistosoma mansoni cercariae or schistosomula attenuated with 20 or 56 krad 60Co irradiation and challenged with 200 cercariae. Protective resistance against homologous strain challenge was compared using the Winches Farm Field Station (WFFS) and Naval Medical Research Institute (NMRI) strains of S. mansoni. Maximal resistance to challenge was obtained in both strains of mice with cercariae or schistosomula of either WFFS or NMRI strain attenuated with 20 krad. Protection using organisms attenuated with 56 krad was significantly lower. Since previous studies with the two parasite strains have shown that the biological effects of irradiation are similar, the difference in the immunogenicity of the 56 krad-irradiated NMRI strain in this study from earlier studies must be due either to different local conditions for irradiation or to adaptation of the NMRI strain to a new laboratory environment. This finding may have important implications for vaccination studies and investigations of the mechanisms of immunity where radiation-attenuated parasites are used. (author)

  16. Licensing of a Type B(U) package design for the transport of industrial 60Co sealed sources and the use as irradiator facility in Argentina

    This paper points out the relevant regulatory issues related to the licensing process of a Type B(U) package design, EMI-9 model, approved for the transport and the use as irradiator facility. The radioactive contents is 60Co sealed sources of up to 2,96 PBq, as a special form radioactive material for industrial use. The correspondent Approval Certificate was issued by the Nuclear Regulatory Authority of Argentina in accordance with the Regulatory Standard AR 10.16.1 that is coincident with the 1985 Edition (As Amended 1990) of the IAEA Regulations. It is described the most significant activities performed during the licensing process as well as brief comments are made on the experience gained from previous Type B(U) package design developments. (author)

  17. Thermoluminescence characteristics of Nd-doped SiO2 optical fibers irradiated with the 60Co gamma rays

    Thermoluminescence (TL) properties (radiation sensitivity, dose response, signal fading) of Nd-doped SiO2 optical fibers irradiated with 1.25 MeV photons to 1–50 Gy were studied. The peak of the glow curve is around 190 °C regardless of the dose. The dose response is linear up to 50 Gy. The radiation sensitivity is 219 nC mg−1 Gy−1. The fiber can be a potential candidate for photon radiotherapy dosimetry due to its high radiation sensitivity, linear dose response in a wide range, slow fading, and high spatial resolution due to the small size of the fiber. - Highlights: • First study of Nd+3 doped optical fibers irradiated by 1250 keV gamma radiation. • Linear response of optical fiber doped with neodymium. • The peak intensity of TL response for 60 Gy is twice that of the 30 Gy. • A potential candidate for photon radiotherapy dosimetry

  18. Influence of rhTPO/GM-CSF fusion protein on hemopoiesis in mice irradiated with 60Co γ-rays

    Objective: To find a new biological therapy for secondary hematopoietic failure including anemia, infection and hemorrhage after administration of chemotherapeutic drugs etc. Methods: hGM-CSF gene was ligated with hTPO gene isolated from human fetal liver mRNA and a new fusion protein rh TPO/GM-CSF obtained. Results: The new fusion protein could promote recovery of peripheral WBC and PLT of 5.0 Gy irradiated mice. BFU-E, CFU-Meg and CFU-GM in bone marrow of mice after irradiation recovered significantly by treatment with rhTPO/GM-CSF fusion protein for 10 days. Conclusion: These results suggest that the new fusion protein has the biological activity of both hTPO and hGM-CSF simultaneously and can stimulate the proliferation of megakaryocytes and granulocyte progenitors

  19. Seabuckthorn leaf extract (SBL-1) counters radiation damage by regulating time kinetics of apoptosis in jejunal crypts in total body 60Co-gamma-irradiated mice

    The radioprotective properties of plant Hippophae rhamnoides L. (common name Seabuckthorn, family Eleagnaceae) were reported and treatment with SBL-1 (herbal preparation from Seabuckthorn leaves), before whole body exposure to 60Co-gamma-rays (10 Gy), rendered >90% survivors in mice population, while 100% mortality was observed in non-SBL-1 treated, 60Co-gamma-irradiated (10 Gy) controls. Purpose of this study was to investigate the early as well as late modifying effects of SBL-1 on radiation induced apoptosis in jejunal crypts and m-RNA levels and protein levels of Bcl2 and Bax. A 30 day study was performed with 8-9 weeks old inbred male Swiss albino Strain 'A mice. Histology study was performed with jejunum to record the time dependent changes in the number of apoptotic cells in Crypts of Lieberkuhn; quantitative reverse polymerase chain reaction was performed to record the time kinetic of changes in m-RNA levels of BcI-2 and Bax genes. The changes in BcI-2 and Bax proteins were also recorded by western blotting. One time administration of SBL-1, prior to lethal whole body irradiation (10 Gy), significantly (p< 0.05) countered the radiation induced increases in cryptal apoptotic cells, Bax levels, and decrease in BcI-2 in a time dependent manner from 24 h till day 30. This study demonstrated that one of the underlying mechanisms of SBL-1 for countering radiation induced GI syndrome was by altering the time kinetics of apoptosis in cryptal cells; besides reducing the early damage. (author)

  20. Effects of 60CoIrradiation Intensity on Watermelon Seed Germination and Seedling Growth%60Co-γ辐射对西瓜种子萌发和幼苗生长的效应

    李玉明; 杨世梅; 纪海波; 方春媛; 潘从祥; 陈年来

    2013-01-01

    In order to investigate the effects of different doses of 60Co-γ radiation on watermelon seed germination and seedling growth, watermelon seeds with different qualities of 12 varieties were used as the test materials to investigate the effects of six different doses of radiation on emergence rate, surviving rate, emergence time, cotyledon area, plant height and stem diameter. The results showed that medium size seeds of watermelon demonstrated a promoting effect on seedling growth under the dose of 200 Gy and 400 Gy. When the radiation dose exceed 600 Gy, all watermelon seeds showed the extremely significant level (P small seed > medium seeds.%为了探讨60Co-γ辐射剂量对不同质量西瓜种子萌发和幼苗生长的影响,以不同质量的12个西瓜品种干种子为材料,通过6个剂量的辐射处理,研究辐射剂量对西瓜干种子出苗率、存活率、出苗时间、子叶面积、株高及茎粗等的影响.结果表明,200和400 Gy辐射对中等种子出苗有促进作用,超过600 Gy都具有显著(P<0.05)抑制作用;随着辐射剂量的增加,植株出苗时间延长,幼苗生长缓慢;根据半致死剂量确定西瓜种子适宜辐射剂量为600~800 Gy.不同大小西瓜种子对60Co-γ辐射的敏感性表现为大种子>小种子>中等种子.

  1. 60Co γ-ray irradiation effect on germination and seedling growth of dry Buchloe dactyloides seeds

    The dry seeds of Buchloe dactyloides were irradiated by γ-ray at dose of 25-300 Gy. Seed germination and seedling characters were surveyed in laboratory and field. The results indicated that radiation could promote seed germination, and the optimum dose was 100 Gy. The dose of 150 Gy was the up limit to germination rate, root length and seedling height in field. When the radiation dose was bellow 100 Gy, the fresh weight of stems, leaves and roots of seedlings were increased. From this study, the recommended radiation does for Buchloe dactyloides dry seeds treatment was between 100-150 Gy for the purpose of promoting germination. (authors)

  2. Chemical changes in the chloroform-paraffin-dye system irradiated with 60Co gamma-rays, 2

    Studies have been carried out on the amount of hydrogen chloride formed by the radiolysis of chloroform in a solid paraffin-chloroform-Methyl Yellow system, and the color changes from yellow to red and absorption energy observed. The amount of hydrogen chloride formed and the intensity of the red color were determined with a pH meter, a spectrophotometer, and a color/ color-difference meter. It was found that the color-difference meter had the most excellent spectral response and sensitivity for measurement of the irradiated sample, and that the color-difference, ΔE, obtained by reflectometry increased proportionally with the increase in the radiation dose throughout a region of 100 -- 5000 R. When a solid sample composed of 1.0 kg paraffin (m.p. 62 -- 640C), 0.74 kg chloroform and 3.4 x 10-3 mol Methyl Yellow was subjected to 1000 R irradiation at 200C, 2.5 x 1014 molecules of hydrogen chloride were formed in 1.0 g of the solid sample with the absorption energy of 5.9 x 1016 eV, 3.2 x 1016 eV of which contributed to chloroform as the absorption energy. (author)

  3. Effect of physical exercise on the state of the heart and central hemodynamics in dogs exposed to external (60Co) and internal (239PuO2) irradiation

    Experiments were conducted on mongrel dogs aged 2 to 4 with the body mass of 15.1 ± 0.9 kg. The animals were exposed to combined and isolated γ-irradiation at a dose of 51.6 mC/kg and submicron 239PuO2 in the amount not less than 7 kBq/kg. Single circular irradiation was provided from 60Co γ-sources at a dose rate of 1.03-1.3 mA/kg. 239PuO2 was inhaled 6 days after irradiation. 20 min. running on a tredbahn with the speed of 4.7 km/h served as a physical exercise model. The dogs were examined 0.5, 1, 1.5 and 4 yrs. after the initiation of the experiment at rest and within 1 h after physical exercise. Methods of tetrapolar chest rheography and electrocardiography were employed. It was shown that in the combined effect of two radiation factors the rates of increase in the cardiac index were inhibited at the expense of physical exercise influence as compared to those in the isolated radionuclide effect and resulted from less ''economical'' heart action

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

    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.

  5. Activity evaluation from different native or irradiated with 60 Co gamma rays snake venoms and their inhibitory effect on Leishmania (Leishmania) amazonensis

    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 LLCMK2 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 60Co 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. 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

    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)

  7. The effect of vitamin A on CD4+ and CD8+ cells irradiated by 60Co γ-ray

    The monocyte-depleted peripheral blood mononuclear cells were separated into CD4+ and CD8+ subpopulations by panning technique with McAb CD4 and CD8. The purity of CD4+ and CD8+ cells was 89.2% and 85.8% respectively, which was estimated by an indirect immunofluorescence technique. The radiosensitivities of CD4+ and CD8+ cells and the effect of DNA synthesis in both cells' subpopulations influenced by Vit A were assessed by 3H-TdR incorporation. The experimental result showed that after γ-radiation in different doses on CD4+ and CD8+ cells, the 3H-TdR incorporation was significantly decreased. The 3H-TdR incorporation rate in CD8+ cells irradiated with addition of 5 μg/ml Vit A increased significantly (p<0.05)

  8. Utilization of an elite rice germplasm-Yangdao 6 with high combining ability created by 60Co γ-irradiation

    Yangdao 6, a new rice variety bred by irradiation induced mutation, is an elite Indica germplasm with a higher general combining ability (GCA) and specific combining ability (SCA) compared with other restorer lines in yield composing traits, including total grains per panicle, filling grains per panicle, seed setting, 1000-grain weight, grain plumpness, yield per plant, etc. Used as a parent with high yield, good quality and multi-resistance, it has a good probability for breeding super-high-yield hybrid combinations both for the 'two-line' and Honglian-type CMS lines. And as a restorer line, it accelerates both the breeding of hybrid combinations and routine cultivars with a mode of 'boat goes up as river rises'. (authors)

  9. 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

    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.

  10. The influence of α-amylase supplementation, γ-irradiation (60Co) as well as long time of storage of wheat grain on flour technological properties

    The varieties of winter wheat, Aria and Beta, were studied. The Aria variety was stored for the period of four years. The part of wheat grain from Beta variety was irradiated with γ rays (60Co). In extracts from wheat kernels and flour protein content, total α- and β-amylolytic activity as well as α-amylolytic activity were determined, α-amylases of native and fungal origin were added to the flour obtained from samples of stored wheat kernels (Aria), irradiated and non-irradiated (Beta). Consequently native α-amylase activity of flour increased by 25% and 50%, respectively. Extensive technological estimation of grain and flour with amylase supplements was carried out. The study included: sedimentation analysis, falling number test, milling experiment, farinogram and extensogram analyses, measurement of the degree of damaged starch and flour colour, as well as baking experiment. The obtained experimental loaves of bread were tested for their ability to remain fresh. It was found out that the stored grain flour was characterized by the highest α-amylolytic activity and the lowest falling number value, whereas the irradiated grain flour showed the highest degree of starch damage and water absorption. When α-amylase supplementation to doughs was not accompanied by either irradiation or storage of grain, it definitely changed their physical properties for the worse. The negative influence of native α-amylases appeared to be less significant than that of fungal α-amylases. The positive influence of α-amylase supplementations, especially of those increasing by 25% the native α-amylolytic activity of flour on volume, and freshness of loaves of bread was observed. (author)

  11. Carcinogenic effect of in utero 252Cf and 60Co irradiation in C57BL/6N x C3H/He F1 (B6C3F1) mice

    C57BL/6N x C3H/He F1 mice were exposed in utero to 0, 1.0 and 2.7 Gy of 252Cf or 60Co at day 16.5th of gestation. Mice of both sexes were observed for 2 years. The females in the irradiated groups showed increases in the incidences of pituitary, mammary gland, liver and lung tumors. 252Cf was more effective in inducing tumors than was 60Co. Interestingly, the incidence of hematopoietic tumors decreased by irradiations with 252Cf but not with 60Co. The incidences of liver tumors in males increased by 252Cf-irradiation, whereas, the incidences of skin and soft tissue tumors increased by 60Co-irradiation. These results indicate that irradiation in utero during the late embryonic stage can induce tumors postnatally after a long latency. Moreover, females irradiated in utero had disfunction of the ovaries, evidence of impairment of the female's specific hormonal environment. This may be the cause of the low incidence of ovarian tumors and the high incidences of liver, lung and pituitary tumors in these female mice. Females with pituitary tumors had a high serum prolactin, which might be responsible for the concurrence of mammary gland tumors. These results indicate the importance of host factors in the development of radiation-induced tumors. (author)

  12. Tachyzoites of Toxoplasma gondii irradiated with 255 Gy induces decrease of cysts and cerebral lesions in mice challenged with cysts of ME-49

    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)

  13. Effects of gamma irradiation of the 60 Co on antimicrobial action of plant extracts of bark and leaves of Schinus terebinthifolius Raddi

    This study aimed to evaluate the potential for antimicrobial activity in vitro of extracts of bark and leaves of S. terebinthifolius treated with 60Co 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

  14. Cloning and molecular analysis of GA2ox1 gene mutation generated by gamma-ray 60Co irradiation in mutagenized Tamxoan - TDB06 rice cultivar

    In the present study, we have used various rice cultivars such as Nipponbare, Tamxoan Hai Hau and mutagenized TDB06 which was obtained from Tamxoan Hai Hau calli irradiated by gamma-ray 60Co with the aim of cloning, sequencing and investigating the molecular mutants of GA2ox1 gene which regulates the height of rice cultivars. Interestingly, we have found that the nucleotide sequence of GA2ox1 gene of mutagenized TDB06 is slightly changed compare to that of original Tamxoan Hai Hau and Nipponbare. The GA2ox1 gene sequence differences of mutagenized TDB06 compared to Tamxoan Hai Hau and Nipponbare are 9 and 2 nucleotides, respectively. We have also shown that the amino acid sequence of GA2ox1 protein is also different among various cultivars in which amino acids corresponding to positions 137 (Alanine), 167 (Threonine), 222 (Valine), 227 (Histidin) of mutagenized TDB06 were replaced with other amino acids Valine, Alanine, Arginine and Lysin, respectively. Nucleotide sequences of GA2ox1 gene isolated from mutagenized TDB06 and Tamxoan Hai Hau cultivars have been registered in Genbank/NCBI with accession numbers EF164903 and EF164904. Based on these initial results, we continuously isolate genes related to dwarf character, construct vectors and do transformation. This strategy can significantly contribute to improve efficiency of rice breeding in Vietnam. (author)

  15. Influence of 60Co γ-ray irradiation and applied bias voltages on dielectric properties of Al/SiO2/p-Si (MIS) structures

    The MIS structures were exposed to 60Co γ-ray source at 5 kGy and radiation effect on dielectric properties has been investigated using admittance method (C-V and G/ω-V) by applying a small ac signal of 40 mV amplitude at 1 MHz and room temperature. The voltage dependent dielectric constant (ε'), dielectric loss (ε''), loss tangent (tanδ), electric modulus(M*) and ac electrical conductivity (σac) profiles show an intersection behavior about 1.6 V. The ε', ε'', tanδ and σac values decrease with increasing dose before intersection point after than they become increase. Such behavior can be explained on the basis of Maxwell-Wagner interfacial polarization and restructuring and reordering of interface states charges due to the effect of γ-ray irradiation. Also, the imaginer part of M* exhibits a peak. It is concluded that all these parameters of MIS structure are strongly dependent on the radiation dose and applied bias voltage especially in depletion region.

  16. Differential radio-sensitivities of human chromosomes 1 and 2 in one donor in interphase- and metaphase-spreads after 60Co γ-irradiation

    Radiation-induced chromosome aberrations lead to a plethora of detrimental effects at cellular level. Chromosome aberrations provide broad spectrum of information ranging from probability of malignant transformation to assessment of absorbed dose. Studies mapping differences in radiation sensitivities between human chromosomes are seldom undertaken. Consequently, health risk assessment based on radio-sensitivities of individual chromosomes may be erroneous. Our efforts in this article, attempt to demonstrate differences in radio-sensitivities of human chromosome-1 and/or -2, both in interphase and metaphase spreads. Upon blood collection, dosimetry and irradiation were performed. Lymphocytes were isolated after whole-blood irradiation with 60Co γ-rays in the dose range of 0–5 Gy for both interphase, and metaphase aberration studies. Induction of premature chromosome condensation in interphase cells was accomplished using a phosphatase inhibitor, calyculin-A. Metaphase spreads were harvested from short-term peripheral blood lymphocyte cultures following colcemid arrest and using an automated metaphase harvester and spreader. Aberration analysis in both interphase and metaphase spreads were done using FISH. In interphase, aberrant cell and aberration frequency involving chromosome 1 and/or 2 increased linearly with radiation dose. In metaphase, aberrations increased in a linear-quadratic manner with dose. Our studies ascertain that chromosome-2 is more radio-sensitive than chromosome-1 in both interphase and metaphase stages, albeit the DNA content of chromosome-2 is lesser than chromosome-1 by almost 10 million base pairs. Differences in radio-sensitivities of chromosomes have implications in genetic damage, chromosome organization, and chromosome function. Designing research experiments based on our vital findings may bring benefit to radiation-induced risk assessment, therapeutics and development of chromosome specific biomarkers

  17. Evaluation of the radio modifier effect of propolis on chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60-CO

    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 60Co γ 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 μg/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 - 400μ/ml) in PC3 cells irradiated with 5 Gγ. The survival curves obtained were adequately fitted by a linear-quadratic model, where the α 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 μg/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 obtained in vitro showed a

  18. Effect of 60Co γ-ray Irradiation on Growth Characteristics of Chamaecrista%60Co-γ射线辐照处理对决明若干生长特性的影响

    翁伯琦; 徐国忠; 郑向丽; 应朝阳; 黄毅斌

    2005-01-01

    利用60℃o-γ射线(辐照剂量为300 Gy,剂量率为4.687 5 Gy/min)辐照豆科决明属5个牧草品种的种子,通过盆栽收集各个品种的M1代种子,然后进行M2代试验与观察.结果表明,辐照后5个决明M2代的种子出苗率、植株的茎长、叶宽均无显著差异;34721号决明植株冠高有显著增长、2219号决明茎径有显著增长、86134号决明分枝数有极显著增长,92985号决明分枝数则有显著降低、86134号决明叶数和地上部植株干重有显著增长、2219号决明叶长增长显著,其余参试品种则无显著差异.植株的营养成分测定表明:仅2219号决明K含量呈显著下降、其他品种的N,P,K含量则无显著差异;2219不仅氨基酸总量呈显著下降、而且17种氨基酸都表现为不同程度的下降,86134氨基酸总量有显著增长、同时17种氨基酸都表现为不同程度的增长,而其余3个参试品种都无显著差异.经60Co-γ射线辐照处理后的34721,86134,92985的酯酶同工酶谱与相应的对照有明显差别.生长观察结果表明,参试的5个决明品种M2代植株生长的现蕾期、初花期、盛花期、初荚期、盛荚期、成熟期表现为双向性,既有提早,也有推迟.

  19. 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

    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)

  20. Luminescence characteristics of C5+ ions and 60Co irradiated Li2BaP2O7:Dy3+ phosphor

    Wani, J. A.; Dhoble, N. S.; Lochab, S. P.; Dhoble, S. J.

    2015-04-01

    In this work a study on some thermoluminescence characteristics of Li2BaP2O7:Dy phosphor is presented. The phosphor was synthesized by solid state diffusion method and characterized for its phase purity by X-ray diffraction (XRD). FT-IR spectrum was also carried out to confirm the presence of phosphate family and vibrations corresponding to P-O-P group. Spectroscopic investigation was approached through photoluminescence (PL) and thermoluminescence (TL). PL emission spectrum of Dy3+ ions corresponding to 4F9/2 → 6H13/2 (483 nm) and 4F9/2 → 6H15/2 (574 nm) transitions is revealed under 351 nm excitation wavelength. This characteristic emission confirms the presence of Dy3+ ions in the Li2BaP2O7 host matrix. To induce TL properties in Li2BaP2O7:Dy phosphor was irradiated with C5+ ion beams and gamma rays (60Co). A nearly simple glow curve was observed for Li2BaP2O7:Dy under two different excitation sources. TL response is almost linear over a wide range. Average absorbed dose (D bar) and mean linear energy transfer (LET ‾) of C5+ ion beams in Li2BaP2O7:Dy have also been calculated. Values of parameters like E and S known as trap depth and frequency factor respectively were obtained by using TLanal computer program. Also SRIM based calculations were performed to study the effect of C5+ ion beams on the samples of Li2BaP2O7:Dy. SRIM calculations show that Ba2+ vacancies are highest in number. Till date no such luminescence information on Li2BaP2O7:Dy phosphor is available.

  1. 6Co γ射线诱发小鼠DNA甲基化改变%DNA methylation changes induced by 60 Co γ-ray irradiation

    黄铖铖; 孙秀锦; 胡明江; 程跃进; 古桂雄; 崔凤梅

    2011-01-01

    Objective To study the change and significance of DNA methylation pattern and DNA methyltransferase (DNMT1) protein in 60Co γ-ray irradiated mice tissues. Methods Twelve SPF C57BL/6J mice were randomly divided in-tocontrol group and radiation group. The radiation group were exposed to 4Gy-single whole body radiation. All mice were sacrificed 3 days after the radiation. The total number of peripheral white blood cells and the frequencies of micronucleated polychromatic erythocytes(fMNPCE) were measured. Methylated DNA immunoprecipitation-chip(MeDIP-chip) was adopted to investigate the differentially expressed CpG islands methylation profiles in mouse liver genome promoter. The immunohisto-chemical(SP method) and western blot method were used to check the expression of DNMT1 protein in tissues. Results Compared with the control group,the promoter methylation profiles of irradiated mice changed obviously, with 1300 genes methylated and 660 genes demethylated. With the improvement of the screening criteria,the obviously methylated genes were Trim71,Sema3f, Pcdh8,Sox4,1110034A24Rik, Limkl, Nefl, and Xprl and the demethylated genes were Sfrsl8,Drl, Ankrd42,Nael ,Sfil ,Accnl ,Srd5al ,Nsun2,Eifla,and Dusp5. Except in the lung,the expression of DNMT1 protein in liver, kidney, testicle, and brain tissues were all increased (P < 0.05). Conclusion There are methylation changes of gene promoter in ionizing radiation injury and the increased expression of DNMT1 may be the reason of gene promoter methylation.%目的 探讨基因组启动子甲基化谱及DNA甲基化酶1(DNMT1)表达量在60Co-γ射线照射小鼠各组织的变化及其意义.方法SPF级C57BL/6J雄性小鼠12只随机分为对照组和照射组,照射组小鼠接受4Gy60 Co-y射线单次全身照射后,均眼球摘除取血后处死,收集各脏器组织,进行外周血白细胞计数和骨髓嗜多染红细胞微核计数,应用甲基化DNA免疫沉淀-芯片(MeDIP-chip)杂交技术对y射线

  2. Protective and/or recovering effects of various kinds of chemicals and drugs to the hemopoietic injuries caused by the irradiation of /sup 60/Co. gamma. -rays in the mice

    Kagimoto, Akio

    1987-01-01

    We have injected eleven kinds of chemical substances and drugs intraperitoneally in the male ddN mice, and studied the relative protective and/or recovering effects of them to the hemopoietic injuries caused by the whole body irradiation of 600R of /sup 60/Co ..gamma..-rays. Good radioprotective activity on bone marrow cells in the irradiated mice was found, when we administered AET (S, 2-aminoethylisothiuronium Br. HBr) before irradiation, 5-HTP (5-hydroxytryptophane) in low dosage before irradiation, Glutathione before irradiation, or Serotonin (5-HT; 5-hydroxytryptamine) in high dosage before irradiation. Good radioprotective or recovering activity was observed on the weight of the spleen, by Serotonin in high and low dosage before irradiation, or DBCC (5,6-dimethyl benzimidazolyl cobamide coenzyme; Vitamin B/sub 12/) after irradiation. Positive responses of reticulocytes, erythrocytes, hemoglobin, and hematocrit were obtained in the irradiated mice, when we administered Serotonin in high dosage before irradiation, MET (S-Methyl-l-cysteine sulfoxide) before irradiation, a cocktail of Periactin (Cyproheptadine hydrochloride) and Serotonin before irradiation, MET before and after irradiation or Nucleo (a mixture of products made by degrading yeast-RNA) after irradiation respectively. A good response in leukocyte count was observed when Serotonin in high dosage before irradiation was administered, and in granulocyte count by Serotonin in high dosage before or 5-HTP in low dosage before irradiation. Lymphocyte count was protected or recovered by Serotonin in high dosage before or Nucleo after irradiation. Thrombocyte count was protected by Serotonin in high and low dosage before, Glutathione before, or AET before irradiation.(author).

  3. Protective and/or recovering effects of various kinds of chemicals and drugs to the hemopoietic injuries caused by the irradiation of 60Co γ-rays in the mice

    We have injected eleven kinds of chemical substances and drugs intraperitoneally in the male ddN mice, and studied the relative protective and/or recovering effects of them to the hemopoietic injuries caused by the whole body irradiation of 600R of 60Co γ-rays. Good radioprotective activity on bone marrow cells in the irradiated mice was found, when we administered AET (S, 2-aminoethylisothiuronium Br. HBr) before irradiation, 5-HTP (5-hydroxytryptophane) in low dosage before irradiation, Glutathione before irradiation, or Serotonin (5-HT; 5-hydroxytryptamine) in high dosage before irradiation. Good radioprotective or recovering activity was observed on the weight of the spleen, by Serotonin in high and low dosage before irradiation, or DBCC (5,6-dimethyl benzimidazolyl cobamide coenzyme; Vitamin B12) after irradiation. Positive responses of reticulocytes, erythrocytes, hemoglobin, and hematocrit were obtained in the irradiated mice, when we administered Serotonin in high dosage before irradiation, MET (S-Methyl-l-cysteine sulfoxide) before irradiation, a cocktail of Periactin (Cyproheptadine hydrochloride) and Serotonin before irradiation, MET before and after irradiation or Nucleo (a mixture of products made by degrading yeast-RNA) after irradiation respectively. A good response in leukocyte count was observed when Serotonin in high dosage before irradiation was administered, and in granulocyte count by Serotonin in high dosage before or 5-HTP in low dosage before irradiation. Lymphocyte count was protected or recovered by Serotonin in high dosage before or Nucleo after irradiation. Thrombocyte count was protected by Serotonin in high and low dosage before, Glutathione before, or AET before irradiation.(author)

  4. 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

    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)

  5. 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

    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)

  6. 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

    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)

  7. Effect of dose-rate of gamma irradiation (60Co) on the anti nutritional compounds phytic acid and antitrypsin on soybean (glycine max L.)

    An investigation on the effect of gamma irradiation at different dose-rate on the anti-nutritional compounds (phytic acid and antitrypsin) and the color of soybean has been conducted. The purpose of the study was to analyze the influence of the dose-rate on the rate of change of anti-nutritional compounds and color. Samples were irradiated with dose-rates of 1.30; 3.17; 5.71 and 8.82 kGy/hour with irradiation time varied from 0.5 to 55 hours. Phytic acid content and antitrypsin activity, as well as their L α b color values were analyzed. Results showed that a simple first order kinetics model can be used to describe changes in the concentration of the anti-nutritional compounds and color soybeans during the radiation processing. Data indicate that irradiation process at higher dose-rate (shorter time) is more effective in destroying anti-nutritional compounds as compared to that of irradiation process at lower dose-rate (longer time). Furthermore, irradiation process at higher dose-rate (shorter time) also have less detrimental effect on color of the soybean and the resulted soybean flour as compared to that of irradiation process at lower dose-rate (longer time). These findings suggest that irradiation process at a same dose may potentially be optimized by selecting the most appropriate combination of dose-rate and time of irradiation. (author)

  8. Comparison of results of the manual and automated scoring of micronucleus frequencies in 60Co-irradiated peripheral blood lymphocytes for triage dosimetry

    Scoring micronuclei in the peripheral blood lymphocytes of individuals exposed to ionizing radiation is a rapid biodosimetry assay. Peripheral blood lymphocytes from five individuals were exposed in vitro to 0–5 Gy of 60Co γ-radiation at a dose rate of 0.76 Gy/min. The blood cultures were initiated with RPMI-1640 (80%) supplemented with FBS (20%), stimulated with mitogen and incubated at 37 °C for 44 h. At the 44th hour, cytochalasin-B (6 µg/mL) was added, and the cultures were incubated for 28 h more. The cells were harvested with a pre-chilled hypotonic solution (0.075 M) and fixed with a Carnoy's solution (methanol/acetic acid 5:1). Giemsa- and propidium-iodide-stained cells affixed to slides for microscopy were scored manually and automatically with the micronucleus scoring software from MetaSystems. The micronucleus frequencies determined in the Giemsa-stained cells by manual and automated scoring were 23.6% different (P<0.0001) with an efficiency of 24.9%. Slides stained with propidium iodide are a better choice for automated scoring than Giemsa-stained ones. - Highlights: • Stains (Giemsa and PI) used did not influence the MN dose response. • No significant variation in the MN yield at lower doses between scoring methods. • Automated scoring of MN in PI stained cells would be the choice for triage

  9. Study on the grafting of N-vinypyrrolidone onto xanthan gum by 60Co γ-irradiation and properties of the grafted copolymer

    Simultaneous radiation grafting method (60Co γ-rays as the radiation source) was used to prepare xanthan gum-graft-N-vinypyrrolidone (XG-g-NVP), and the influence factors of the grafting degree was preliminarily studied. The structure of the grafted copolymer was characterized by the Fourier-transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA), and the solution viscosity properties of the grafted copolymer in low grafting rate were studied by rheometer. The results show that the grafting rate increases with absorbed dose and gradually achieve to the balance. The grafting rate reaches maximum when the xanthan gum concentration is 10 g/L or the mass ratio is 10:1 meanwhile the other two factors are in a certain experimental value range. FT-IR figure shows that the grafting reaction occurs in NVP vinyl part and lactam structure is retained. Thermo-gravimetric analysis shows that XG-g-NVP enhanced thermal stability of xanthan gum. The properties of XG-g-NVP solution show that grafting to enhance the performance of resisting high temperature and shear strength. (authors)

  10. Microstructural study of Y1Ba2Cu3O7-x/Ag samples irradiated with 60Co γ rays at high doses

    We have investigated the damage induced by irradiation in Y1Ba2Cu3O7-x silver added samples. The samples were prepared with 0 and 6.5 wt% of silver and irradiated by high-energy γ irradiation (50-150 Mrad). The roles of silver and dosage irradiation are discussed in terms of their effects on microstructure, crystallinity, critical temperature (Tc) and zero-resistance temperature (T0). After irradiation, Tc decreased while the room-temperature electrical resistance increased by a factor of 8 for some of the samples. The difference in T0 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, Jc decreased because of the weak-link breakage induced by high doses of γ rays. (author)

  11. Analysis of the chromosome damage and repair kinetics in CHL cells after 6'0Co γ-irradiation by PCC technique

    The kinetics of chromosome damage and repair was determined by PCC. Chromosome damage repair was not detectable until 30 min after irradiation and nearly half of chromosome damage was repaired by 6 h. In contrast, significant DNA repair occurred at 5 min after γ-irradiation measured by FADU technique. These results suggest that the early repairing DNA SSBs are not important in the formation of chromosome aberration, the different repair kinetics between DNA and chromosome damages might reflect their different repair mechanism

  12. 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

    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.

  13. Changes of gene expression of platelet-derived growth factor-β and transforming growth factor-β1 mRNA in wound tissues after 60Co γ-irradiation and role of phenytoin sodium

    Objective: To study the changes of gene expression of growth factors in wound tissues after 60Co γ-irradiation and the role of phenytoin sodium. Methods: Wound tissues were collected from dorsum incision in rats, in which polyvinyl alcohol sponges had been implanted. The expressions of platelet-derived growth factor-B (PDGF-B) mRNA and transforming growth factor-β1 (TGF-β1) mRNA in wound tissues were determined by in situ bybridization. Results: It was found that the expressions of PDGF-B mRNA and TGF-β1 mRNA were decreased after 6 Gy whole-body irradiation, and phenytoin sodium significantly increased the expressions of PDGF-B mRNA and TGF-β1 mRNA in both irradiated and non-irradiated wounds. Conclusion: It is suggested that the decrease of expressions of growth factors in wound tissues plays an important role in the impairment of wound healing by systemic irradiation. Phenytoin sodium enhances the expression of growth factors in wound and helps improve wound healing

  14. Performance of p-bulk microstrip sensors under {sup 60}Co γ irradiation at rates expected at the HL-LHC

    Takahashi, Y. [IPAS, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan); Hara, K., E-mail: hara@hep.px.tsukuba.ac.jp [IPAS, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan); Kim, S. [IPAS, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan); Ikegami, Y.; Takubo, Y.; Terada, S.; Unno, Y. [INPS, High Energy Accelerator Research Org. (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Mitsui, S. [Sokendai, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Kamada, S.; Yamamura, K. [Hamamatsu Photonics Co. Ltd., Ichino, Hamamatsu Shizuoka 435-0051 (Japan)

    2013-01-21

    We are developing p-bulk microstrip sensors for the high luminosity upgrade of the LHC accelerator, HL-LHC. The stability of FZ (float zone) wafers available to Hamamatsu Photonics was examined by irradiating them at rates expected at the HL-LHC. They show degradation in the operational voltage at low dose but recover after the dose is accumulated. The instability is dependent on the bias voltage and dose rate, and also on the irradiation history. We have characterized the instability and attributed the cause to the charge concentration at the electrode edge. The strip isolation, which is degraded while in irradiation, is shown not to induce any practical problem for the operation.

  15. Study of the effect of gamma irradiation (60 Co) on the quality of sugar cane spirit and on the cask of maturation

    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)

  16. Study of the effect of gamma irradiation (60CO) on the quality of sugar cane spirit and on the cask of maturation

    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)

  17. Severe acute radiation syndrome. Treatment of a lethally 60Co-source irradiated accident victim in China with HLA-mismatched peripheral blood stem cell transplantation and mesenchymal stem cells

    This is a case report of a 32-year-old man exposed to a total body dose of 14.5 Gy γ-radiation in a lethal 60Co-source irradiation accident in 2008 in China. Frequent nausea, vomiting and marked neutropenia and lymphopenia were observed from 30 min to 45 h after exposure. HLA-mismatched peripheral blood stem cell transplantation combined with infusion of mesenchymal stem cells was used at Day 7. Rapid hematopoietic recovery, stable donor engraftment and healing of radioactive skin ulceration were achieved during Days 18-36. The patient finally developed intestinal obstruction and died of multi-organ failure on Day 62, although intestinal obstruction was successfully released by emergency bowel resection. (author)

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

    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.

  19. Effects of 60Co gamma irradiation on Eimeria falciformis (Eimer 1870) Schneider 1875, a protozoan parasite of the mouse, Mus musculus L

    Oocysts of an E. falciformis strain first isolated in Wuppertal, Germany were exposed to cobalt-60 gamma radiation under different conditions of oocyst age and development. In order to construct survival curves for oocysts irradiated in the unsporulated state, normalized percent sporulation was plotted as a function of radiation dose. Oocysts irradiated in the sporulated state never caused infection after receiving doses of 50 krads or more. Rarely, oocysts which had received 40 krads produced infection and completed their life cycle in susceptible hosts, but usually the doses beyond which infection did not occur ranged from 30 to 35 krads. Immunity was shown best by hosts which had received unirradiated oocysts in vaccinations prior to challenge. When irradiated sporulated oocysts were used in attempts to immunize susceptible hosts against coccidiosis, the most positive results were obtained from oocysts which had been exposed to 20 krads. Animals receiving vaccinations of oocysts exposed to 20 krads always survived the minimal infections caused by vaccination and also exhibited good immunity to challenge

  20. Effects of restrain and regulation on production of β-adrenergic receptors in lung of Sprague-Dawley rats by 60Co γ-ray irradiation

    Objective: To study the restrain and regulation on production of β-adrenergic receptors in Sprague-Dawley rat lung by 20 Gy γ-ray irradiation. Methods: To determine production of β-adrenergic receptors (Bmax) after irradiation and BAAM irreversible blockade by radioligand binding assay of receptors. Results: β-adrenergic receptors were sensitive to γ-rays, and the sensitivity level declined to the lowest on day 20 after radiation, then the receptors were recovered gradually. But the receptor production rate (Pr) was slower, i. e., Pr was (0.36±0.03) x 109 sites/mg protein/h [control groups, (8.20 ± 1.47) x 109]. The half-time of update (T1/2 ) was put off for 10.9 days as compared to BAAM group. Conclusion: Production of receptors can be restrained by 20 Gy γ-ray irradiation, resulting in lower receptor production rate, and longer half-time of update (T1/2 ). (authors)

  1. 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

    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)

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

    The objective of present study was to assess the effect of Brazilian propolis (AF-08) on CHO-K1 cells irradiated with 60Co, 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)

  3. 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

    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)

  4. 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

    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

  5. 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

    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/60Co) 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 107 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 vaccines could be

  6. Effect of Irradiation of 60CO Gamma Rays on Growth of Garlic (Allium Sativum L) Plants Cv. Lumbu Hijau at Low Land Area

    Garlic originally come from the sub tropical area. In Indonesia, garlic is grown generally in high land area with an altitude between 1000 - 1600 m above sea level. Therefore, the area for growing and producing garlic is limited. Besides, genetic variation of garlic is very narrow since garlic belongs to vegetatively propagated crops. An effort for increasing genetic variation of garlic was done by exposing garlic cloves to gamma rays in order to obtain garlic mutant lines adapted to low land area. Garlic cloves were exposed to different doses of gamma rays 0 (untreated) 2, 4, 6, 8 and 10 Gy at the Centre for Research and Development of Isotope and Radiation Technology. Each dose consisted of 150 garlic cloves. Untreated and irradiated garlic cloves were grown at Bandar Buat Experimental Station (50 m above sea level), Padang, West Sumatera. The experiment was arranged in a randomized block design with three replication. The parameter observed were percentage of grown plants and survival harvested plants, plant height, leaf number, chlorophyll content, number of stomata, plant age, number of cloves per bulbs, fresh, dry weight and diameter of bulbs. The result indicated that the dose of gamma rays 6 Gy is an advantage dose for obtaining well adapted garlic mutant lines in the low land area. (author)

  7. Study of recombination processes for 'electron-hole' pairs in germanium irradiated by γ rays from 60Co using the photovoltaic effect in P-N junctions

    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 γ rays from a Co60 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: σp = 4 X 10-15 cm2 and σn = 3 X 10-15 cm2. The value of σn 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 σp ≥ 10-14 cm2. 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)

  8. Detection Method of TOXOPLASMA GONDII Tachyzoites

    Eassa, Souzan; Bose, Chhanda; Alusta, Pierre; Tarasenko, Olga

    2011-06-01

    Tachyzoites are considered to be the most important stage of Toxoplasma gondii which causes toxoplasmosis. T. gondii is, an obligate intracellular parasite which infects a wide range of cells. The present study was designed to develop a method for an early detection of T. gondii tachyzoites. The method comprised of a binding assay which was analyzed using principal component and cluster analysis. Our data showed that glycoconjugates GC1, GC2, GC3 and GC10 exhibit a significantly higher binding affinity for T. gondii tachyzoites as compared to controls (T. gondii only, PAA only, GC 1, 2, 3, and 10 only).

  9. Effects of 60Co administration on early placental cells

    The effects of 60Co administration on early placental cells were studied. Placental tissue and embryo obtained by induced abortion (6 - 13 weeks gestational age) were placed in the minimal essential medium (MEM) and irradiated with various doses of 60Co. After irradiation, the villi were cultured in a CO2 incubater at 370C. Cell growth process was observed every day with the phase-contrast microscope. Between 1 and 5 days epitheloid cells were dominant, but from about 7th day on fibroblastic cells dominated the culture. In placental tissue irradiated with 100, 200, 500 rad, fibroblastic cells began to grow earlier than in non-treated. Over 3000 rad 60Co inhibited the growth of cells and a culture was impossible. For each dose, the tissue was incubated for various periods of time, exposed to tritiated thymidine for the last hour and autoradiogram was prepared by the dipping method. The labeling index of irradiated trophoblasts showed a significant decrease compared with controls. A chromosome study was made in irradiated in vitro cell lines of fetus and placenta. There was no significant difference between the two cell lines concerning the frequency of chromosome aberration, which tended to increase as the chromosome becomes longer. It is concluded that the trophoblast is highly radiosensitive and that irradiation early in pregnancy may damage DNA synthesis in the trophoblast, and induce abortion. (author)

  10. Metabolism of 60Co in mollusca

    After mollusca were bred in 60Co-labeled sea water or were given 60Co-labeled feed for certain hours, their tissues including the liver were removed as experimental samples. 60Co metabolism was observed by the Sephadex gel filtration profile. A gel chromatogram of the liver in gastropoda showed a marked peak of 60Co on the high-molecular side. Although the peak was observed on both high- and low-molecular sides in pelecypoda, it was more marked on the high-molecular side than on the low-molecular side. In cephalopoda, the peak pattern was similar to that in the other mollusca, but the proportion of low-molecular components was comparatively large. The gel filtration profile of 60Co in various tissues of cephalopoda revealed the incorporation of 60Co into the high-molecular components in blood, three peaks in the kidneys, and the incorporation of 60Co into the low-molecular components in the branchial heart. The metabolism of 60Co was dependent upon the chemical form of Co in gastropoda, and organic 60Co was specifically observed in the high-molecular components. (Namekawa, K.)

  11. The Research on Effect of 60CoγIrradiation on Radiolysis Behavior of BOPA/CPP Packaging Materials by GC/MS%气相色谱质谱联用法分析60Coγ对包装材料双向拉伸尼龙/流延聚丙烯(BOPA/CPP)的辐解行为的影响

    王宽强; 贺承启; 张勋龙; 彭秧

    2015-01-01

    This article researched radiolysis Behavior of 60 Coγirradiated BOPA/CPP Packaging Material by GC/MS. In full scan mode,all the 60 compounds were determined by spectrum,the mainly new radiolysis products were benzene,1,3 bis (1,1-dimethylethyl)and 2,5-Cyclohexadiene1,4-dione;At the same time,the contents of benzene,1,3,bis(1,1-di⁃methylethyl);Phenol,2,4-bis(1,1-dimethylethyl);2,5-Cyclohexadiene1,4-dione;Phenol 2,6--bis(1,1-dimethyleth⁃yl ) ,2,6-bis(1,1-dimethylethyl);Bis(cis-13-docosenamido)methane had obvious changes ,but the other radiolysis products had few changes at different irradiation intensities.%利用气相色谱质谱联用法研究了,受不同强度60Coγ辐照的包装材料BOPA/CPP的辐解行为;经过谱库检索,共检出60多种辐解产物,其中新检出主要的辐解产物有1,3-二叔丁基苯、2,6-二叔丁基苯醌;在不同的辐照强度下,1,3-二叔丁基苯,2,4二叔丁基苯酚,2,6二叔丁基对苯醌,4-乙基,2,6-二叔丁基苯酚,顺芥酸酰胺等物质发生了较明显的变化,其余辐解物没有发生太大的变化。

  12. 60Co levels in the seawater regions

    In order to assess the contribution from nuclear power facilities to the 60Co levels in seawater regions, it is essential to grasp the background values of 60Co. The following matters are described: 60Co sources and the respective inputs; nuclear test fallout and nuclear power plants; the 60Co levels in overseas countries; the 60Co levels in Japan; the 60Co levels from nuclear power plants in Fukui prefecture. In the seawater regions around Japan, there have been numerous instances of 60Co detection; several pCi/kg of dry earth in sea bottom earth and about 1 pCi/kg of raw material in marine life can be considered as the background levels due to nuclear test fallout and nuclear-powered submarines. In the seawater regions of Fukui prefecture, the 60Co levels appreciably exceeded the above background due to the nuclear power plants, which are insignificant concerning the radiation exposure of the local people. (Mori, K.)

  13. 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

    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

  14. 60Co-γ射线辐射对美女樱·菠萝菊根长·芽长及出芽率的影响%Effect of the Treatment with 60Co-γ Ray Irradiation on the Germination Rate and the Length of Bud and Root of Verbena hortensis and Carthamus tinctorius

    吴光升; 强继业; 陈立

    2005-01-01

    对美女樱和菠萝菊种子进行4种剂量的60Co-γ射线处理,结果显示:40Gy的辐射剂量可促进美女樱出芽率,而10、20、80Gy的辐射剂量抑制出芽率.辐射剂量和芽长、根长呈正相关.80Gy辐射剂量对美女樱的出芽率、芽长、根长较适宜.对菠萝菊而言,辐射剂量和出芽率、根长呈负相关.辐照对菠萝菊种子起抑制作用,说明菠萝菊不适合此范围的高剂量辐照.其中辐射剂量为20、80Gy时,菠萝菊种子不发芽;辐射剂量为40 Gy时,芽长达到了4.91 mm,远远大于对照0.57 mm.

  15. Sorption of 60 Co on inorganic solids

    The behavior of sorption of the 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, MnO2, SnO, TiO2, activated carbon and calcinate hydrotalcite was investigated. It was found that the best sorbents of the 60 Co was the MnO2, activated carbon and TiO2 whose sorption was incremented when increasing the pH value of the aqueous solutions, in the one case of the hydrated oxides, the 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)

  16. 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

    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)

  17. Effect of 60Co radiation on peritoneal cells

    This work deals with the effect of 60Co gamma irradiation on the levels and quality of peritoneal cells of albino mice. The cells were obtained from peritoneal exudate, fixed and stained in 30% glacial acetic acid containing 0,5% cristal violet. Os exudates from irradiated and control animals the qualitative analysis and the counting of different cell populations were performed one hour, three days and six days after irradiation with 9 Gy. All the cell populations from the peritoneal exudate shown a decrease 3 days after the irradiation with 9.0. Gy but the different cellular populations dimished in unlike proportions. The data reaffirm the discrepance in radiosensivity of the diverse peritoneal cell populations. (author)

  18. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818) DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818)

    Elaine Barros da Costa CARVALHO; Melo, Ana Maria Mendonça de Albuquerque; Mauricy Alves da MOTTA

    1999-01-01

    The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony...

  19. 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

    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

  20. Disturbed tooth formation by 60Co-gamma-ray radiation

    The molar of guinea pigs was irradiated with 60Co-#betta# ray for daily observations of the manifestation of disturbed tooth formation by microradiography and the time registration by tetracycline-labelling. Irradiation first injured young blast cells of the dentin in the growth phase, dental pulp cells, and cells of the enamel. The portion composed of injured cells formed a depressed ''constriction'' from the dental pulp side toward the border between the enamel and dentin. The cells of the enamel injured by irradiation in the growth phase later formed a very thin irregular stroma. In contrast, cells in the differentiation or subsequent phase at the time of irradiation and cells probably having started to grow after irradiation proceeded with formation of a normal stroma and calcification. No uniform relation was obtained between the histological staining of the organic stroma of normal or abnormal dentin and calcification. Labelling with tetracycline revealed that the irradiation conditions in the present study provoked hardly any changes in the speed of tooth eruption. (Chiba, N.)

  1. Initial research of screening for the differentially expressed proteins in beagles irradiated with 4.5 Gy 60Co γ-rays by two-dimensional gel electrophoresis and mass spectrometry

    Objective: To explore the mechanisms of cytokines on acute radiation disease in irradiation beagles. Methods: The sera of beagles irradiated with 4.5 Gy γ-rays with cytokines treatment was collected at different time points post irradiation. The two-dimensional gel electrophoresis (2-DE) was differentially expressed proteins with significance, and the amino acid sequences should be determined. Results: High resolution 2-DE gel map was obtained. There were six differentially expressed proteins in sera of irradiated beagles at different time points. Four protein spots were successfully identified by MS. A significant spot was identified as serum amyloid A (SAA) by HD-MS, with relative molecular mass of 13 077 and isoelectric point of 6.26. Expression of SAA was not found 1 d pre-irradiation and 36 d post-irradiation, but increased slightly 1 d (0.2166) and significantly 14 d post-irradiation (0.4577). Conclusions: The expression of serum amyloid A was consistent with the process of acute radiation injury, which might indicate the turnover of the disease. (authors)

  2. 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

    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)

  3. Vehicle mobile 60Co container inspection system

    This paper presents a mobile 60Co container inspection system (CIS) and its performance. With all devices including industrial 60Co source, high sensitive gas-ionized array detector, image treatment and control system, inspection driving device on a vehicle, the vehicle mobile CIS has advantages of high agility and climate resistance, and it can complete emergent inspection. The mobile CIS contains equipment-vehicle and control-vehicle. Equipment-vehicle and object-container are still, while a folding detector gantry is moving through a folding rail on the equipment-vehicle and completes the inspection. the mobile CIS has the inspection characteristics similar to the fixed system and it can be used in worse circumstances. Its CI (Contrast Indicator) and IQI (Image Quality Indicator) for 100 mm steel plate attain to 0.5% and 2.5% respectively, and the SP (Space Penetration) is about 240 mm (Fe). Maximum dose per scanning is about 5 μGy, scanning speed is varied from 6 to 18 m/min, and maximum transformational speed is 90 km/h

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

    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)

  5. Different gamma ray (60 Co) dose effects on Sorghum genotype germination

    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 60Co 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 60Co 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 60Co-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 60Co 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 60Co doses. (author)

  6. The possible use of 60Co irradiation attenuated vaccine for the control of human Leishmaniasis in Ethiopia. Part of a coordinated programme on the use of nuclear techniques in the preparation of vaccines against parasitic diseases

    Radiation effects and the evaluation of radiation-attenuated organisms as vaccines was studied with Leishmania enriettii infections in guinea pigs. The use of heat-killed or live but radiation-attenuated promastigotes with or without the concurrent use of BCG as adjuvant failed to elicit protection to challenge with normal virulent organisms. The effects of varying several factors such as irradiation dose, internal from vaccination to challenge, and the use of irradiated macrophages infected with leishmanial organisms failed to elicit protective immunity

  7. Effect of 60 Co gamma radiation on crystalline proteins

    In order to study the effects of 60 Co gamma radiation on crystalline proteins an in vitro system was set up. For that, aqueous solutions from bovine crystalline were used irradiated with 0, 5.000, 10.000, 15.000, 20.000 and 25.000 Gy. The treatment led to protein alterations determined by different methods. By turbidimetry the formation of aggregates that increased with the radiation dose was revealed. The same observation was done from viscosity data and from the UV spectrum of the samples. From amino acid analysis and fluorimetry determinations, tryptophan appeared as the most sensitive amino acid. An increase in the free-S H-groups was also observed. After the standardization of the method, the radio modifier capability of glutathione, amino ethyl thiourea, mercapto ethyl alanine and dimethyl sulfoxide was tested. The results showed that in the presence of those substances the radiation effect was diminished. (author)

  8. Inhibition of MAPK and PKC pathways by 60Co γ-radiation in cultured vascular smooth muscle cells

    Objective: To investigate the signal transduction pathways inhibited by 60Co γ-radiation in cultured vascular smooth muscle cells (VSMC). Methods: The cultured VSMC were irradiated with 60Co γ-radiation of 3.5, 7.0 and 14 Gy respectively. VSMC proliferation was measured by 3H-TdR incorporation, while PKC, MAPK activities were determined by radioactivity assay. Results: Proliferation of VSMC was inhibited by 7.0, 14 Gy 60Co γ-irradiation and the activities of PKC, MAPK were decreased significantly. Conclusion: Inhibitory effect of 7.0, 14 Gy 60Co γ-irradiation on proliferation of VSMC might be resulted from decrease of the activity of PKC, MAPK

  9. Radiation effects of polyolefin elastomer by 60Co γ-rays

    Polyolefin elastomer was irradiated in air or N2 to different doses by 60Co γ-rays. Gel fraction, mechanic performance and flame retarding property of the irradiated POE were investigated. G value of the POE crosslinked in air or N2 is 0.13 and 0.14, respectively. Gel fraction of the irradiated POE increased with both absorbed dose and sensitizer content, and the value of tensile strength and oxygen index (OI) increased to some extent after irradiation. The value of break at elongation decreased slightly after irradiation. (authors)

  10. 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

    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)

  11. Accumulation and excretion of 60Co by marine organisms

    The biological half-life of 60Co accumulated from seawater by marine fish was 20-50 days. It was slightly longer in the liver and muscles than in the whole body. Feed including natural feed organisms contributed more to the total body burden of 60Co than environmental waters. The total body burden of 60Co via feed varied according to the organism species, kinds of feed and the root of incorporation. Transfer ratio of 60Co from the water into the organisms was higher than that from the marine sediments having high affinity of Co into the organisms. The elevated water temperature promoted the biological activity, resulting in the increased bioaccumulation of radioactive Co. Concentration coefficients of 60Co by mollusca and seaweeds were generally high. In particular, organic 60Co was more likely to be accumulated than inorganic 60Co. The biological half-life of organic 60Co was longer than inorganic 60Co in mollusca, while it was the same as or shorter than inorganic 60Co in the other organisms. (Namekawa, K.)

  12. Effect of 60CO radiation processing in mate (Ilex paraguariensis)

    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 60Co at doses 0, 3, 5, 7 and 10kGy 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 10kGy 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 10kGy 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 and

  13. Effect of 60Co radiation processing in mate (Ilex paraguariensis)

    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 60Co 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 and

  14. Responses of commercial broiler chicks to 60Co gamma-rays

    A total of 360 chicks of Nichols line at one-day old were used in this study. Within each sex, the chicks were divided into three exposure treatments (non-irradiated, 400 rads and 800 rads). The source of irradiation was 60Co gamma-rays. The results can be summarized as follows: Of the 360 chicks used in this study, only 10 chicks died during the experimental period. Radiation induced a reduction in body weight in both sexes during the growth period. Gamma-rays reduce the feed intake in both sexes. Moreover, the feed conversion ratio for the irradiated chicks was higher than that the non-irradiated birds. While red blood cells and hemoglobin content were higher in the irradiated chicks, white blood cells count and especially lymphocytes did not affect by 60Co gamma-rays. Gamma-rays had no effect on carcass, bone, meat and giblets as fractions of body weight in both sexes. Moreover, meat water content decreased and meat fat content increased in irradiated chicks. The total length and the total weight of the GI tract decreased due to 60Co gamma-rays. The response of the different regions of the GI tract to this rays is different. Moreover, the effect of this radiation on the GI tract is dependent upon the body weight irrespective of the sex. (orig./MG)

  15. Transfer of 60Co from midwater squid to sperm whales

    Sperm whales are notable squid-eaters. They feed mainly on medium to large-sized cephalopods at midwater levels and defecate near the surface. This suggests the existence of an upward transport of 60Co by sperm whales from the mesopelagic zone (150-1,200m). To elucidate this squid-whale route for this artificial radionuclide, 60Co content was determined in squid and in predator whales captured by commercial whaling. In the Cephalopoda livers 60Co levels of 30-500 mBq kg-1 wet were found and in the viscera of Odontoceti (toothed whales) 15-40 mBq kg-1 wet. About 0.3% of 60Co ingested was estimated to be retained in a 23-year-old male sperm whale. In the livers of Bryde's whales, 60Co levels of 40-80 mBq kg-1 wet were detected, but not in euphausiids and sardines, their possible prey. The level of Co in sperm whales was nearly the same as in Bryde's whales. Specific radioactivity 60Co/59Co in mBq μg-1 was several times higher in sperm whale (1.1-1.6) than in cephalopods (0.19-0.77). Eating prey with a high content of 60Co in the 1960's may have contributed to the present body burden in sperm whales with a long-life span. However, the origin of 60Co in Bryde's whales is unknown. (author)

  16. Research and construction of 60Co container inspection system

    The author presents a special kind of container inspection system, in which the radiation source is a 60Co industrial radiography source of 100-300 Ci. By the adoption of special high sensitivity array detector and other technical solutions, this 60Co container inspection system possesses nice properties. Its 'image quality indicator (IQI)' and 'contrast indicator (CI)' for 100 mm steel plate are equal to 0.7% and 2.5% respectively. Its 'steel penetration (SP)' is about 240 mm. The 60Co container inspection system is much cheaper and more reliable than the accelerator inspection system, and the area for its installation and operation is much smaller. The 'Steel Penetration (SP)' of 60Co system is much higher than that of X-ray machine inspection system. The another merit of 60Co system is the feasibility of designing and constructing a movable type

  17. Radiolysis of saturated phospholipids. [/sup 60/Co

    Handel, A.P.; Nawar, W.W.

    1981-06-01

    Volatile radiolysis products of 1,2-dipalmitoyl-sn-glycerol-3-phosphoethanolamine were recovered by cold-finger distillation and analyzed by gas chromatogrphy and mass spectrometry. They include series of n-alkanes, 1-alkenes, n-alkanals, 2-alkanones, 3-alkanones, 4-alkanones, and methyl and ethyl esters. Quantitative analysis showed that the amounts of products from irradiated 3-sn-phosphatidylethanolamine were strikingly different from those recovered from the acylglycerols. Nonvolatile radiolytic products were separated by thin-layer chromatography. These included palmitic acid, palmitone, lysophosphatidylethanolamine, ethanolamine phosphate, and five unidentified compounds. Possible mechanisms for the formation of these compounds are discussed.

  18. Dosimetric response of united, commercially available CTA foils for 60Co gamma rays

    The usefulness of two kinds of untinted CTA foils: Fuji CTR-125 dosimetric foil and technical CTA-T foil, produced by 'Zaklady Chemiczne, 'Gorzow Wielkopolski' as support for light-sensitive layers of amateur photo-films, for 60Co gamma ray dosimetry was investigated. In spite of rather bad physical parameters of the technical foil (spread of foil thickness, high and different initial absorbance) the dosimetric response of both foils for 60Co gamma rays was similar. The CTA-T foil can be used for routine dosimetry providing that dosimetric signals have to be calculated exactly as recommended by the ASTM (American Society for Testing and Materials) standard, i.e. as the difference of absorbance of irradiated and (the same) non-irradiated foil. Any other approach may lead to high errors of dose evaluation. The last is true also for other CTA foils, especially after long self-life. (author)

  19. The effect of 60Co gamma radiation on human serum gamma-globulin

    The effect of 60Co gamma radiation on human serum gamma-globulin was studied in vitro experiments. Solutions of 0.5 percent gamma-globulin were exposed to 0.2, 0.5, 1.0 and 1.9 Mrad doses 60Co gamma irradiation. Experiments showed that electrophoretic mobility of serum gamma-globulin decreased after gamma irradiation. No significant change in gamma-globulin UV absorption spectrum was observed at 0.2, 0.5, 1.0 and 1.9 Mrad doses. Gamma-globulin becomes progressively less soluble in water as the radiation doses is increased. Radiation induced transformation into insoluble gamma-globulin agregates and scission products. (author)

  20. Study on the radiation research of differentiation state oxalis triaggularis purpurea regeneration system by 60Co γ-rays

    To study the mutation method of Oxalis triangularis purpurea, the Oxalis triangularis purpurea regeneration system generated from the leaf was irradiated by 60Co γ-rays. It shows that the number of adventitious bud and root induced from the differentiation state Oxalis triangularis purpurea regeneration system are cut down with the increment of absorbed doses. After growth seedling length has not distinctly reduced while the absorbed dose is 10 Gy. And it has reduced at 25 Gy and 50 Gy of 60Co γ-rays irradiation with the differentiation state tissue of Oxalis triangularis purpurea. The mutation, such as leaf number, leaf colour and leaf shape mutation, mainly the leaf number mutation (76% of the total mutation) occur in the 60Co γ-rays irradiated group. The M2 mutation rate is 2.9%, and the main mutations are leaf number mutations. (authors)

  1. 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

    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

  2. A positron 1D-ACAR spectrometer for the study of 60Co containing materials

    In order to study some micro-structural changes in irradiated nuclear reactor-pressure vessel steels using a positron annihilation technique, a new three-detector set-up, suitable for a positron 1-dimensional angular correlation of annihilation radiation (1D-ACAR) study of 60Co-containing materials, was developed. The design of the equipment as well as results from test measurements are described. (orig.)

  3. Mutant in tobacco anther culture induced by 60Co γ-rays

    The tobacco anthers at uninucleate eccentric stage were irradiated by 60Co γ-rays for the purpose of inducing desirable mutants. The results showed that the induction frequency of plantlets increased following 1kR of 60Co γ-rays treatment. However, the time of plantlet induction was delayed and the percentage of responding anthers as well as the number of plantlets induced per anther significantly decreased after 3kR of 60Co γ-ray radiation which was considered as a semilethal exposure. The plantlet numbers induced per anther were extremely low following 6kR of 60Co γ-ray radiation. A white flower mutant appeared in the induced progenies. The tobacco leaf quality of this mutant were significantly improved as compared with its parental line. The mutant line has been tested and proved to have commercial value though the resistance to the black shank of tobacco slightly decreased as compared with the parental line

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

    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.

  5. 60Co retention by a freshwater planktonic alga Scenedesmus obliquus

    This paper presents the results of various decontamination experiments aimed at evaluating 60Co retention by Scenedesmus obliquus, and the respective role played by absorption and adsorption in the contamination of the alga by this radionuclide. The physiological condition of cells is not involved in radiocobalt desorption, which seems to indicate that the phenomenon is of a passive nature. When the precontamination time is extended, the proportion of adsorbed 60Co decreases, and the final percentage of radionuclide retained increases. These results are confirmed by bringing cells into contact with a strong chelating agent. The elimination of 60Co in the presence of EDTA undergoes a sharp decrease which is correlated with the increase in the duration of the precontamination phase. The use of a weaker complexing agent, such as NaCl, leads to the hypothesis of there being 2 types of 60Co receptor on cell membranes. (author)

  6. 60Co照射后豚鼠内耳前庭终器毛细胞损伤及凋亡的实验研究%INJURY AND APOPTOSIS IN VESTIBULAR APPARATUS OF INNER EAR IN GUINEA PIGS AFTER 60Co IRRADIATION

    孙贝蒂; 唐安洲; 谢利红

    2012-01-01

    目的:探讨60Co照射后豚鼠内耳前庭终器损伤与caspase-3、bax及bcl-2表达的关系及照射后前庭功能的损伤情况.方法:将白化豚鼠40只随机分为正常对照组和照射组(1,4,14,30 d组),每组8只.照射组豚鼠右耳颞部做一次性60Coγ射线照射40 Gy.分别于照射前、照射后1,4,14 d及30 d行冰水试验后处死,取出听泡,行前庭终器切片、HE染色、免疫组化染色,并分离囊斑及壶腹嵴,行超薄切片透射电镜检查.结果:冰水试验照射组眼震时间较对照组缩短,差异有统计学意义(P<0.05),照射后30 d组眼震时间较其他照射组长,差异有统计学意义(P<0.05).照射组豚鼠的囊斑较对照组感觉上皮层厚度变薄,毛细胞数量减少,纤毛变短、减少,照射组壶腹嵴耳石层消失,纤毛消失.透射电镜显示,照射后各组的囊斑及壶腹嵴均可见受损的毛细胞,受损毛细胞线粒体肿胀,以30 d为明显,线粒体嵴变短减少并且发生断裂.照射后各组囊斑caspase-3、bax、bcl-2表达较对照组增强,差异有统计学意义(P<0.05).照射后30 d组囊斑、壶腹嵴caspase-3表达强度较其他对照组减弱,差异有统计学意义(P<0.05).照射后4 d组囊斑、壶腹嵴bax表达上调程度较bcl-2表达上调程度强,差异有统计学意义(P<0.05),bax/bcl-2上升.照射后30 d组囊斑、壶腹嵴bcl-2的上调程度较bax表达上调程度强,差异有统计学意义(P<0.05),bax/bcl-2下降.结论:凋亡相关蛋白caspase-3的表达上调及bax、bcl-2的不均衡表达上调可能在60Coγ射线造成的前庭损伤中起重要作用.%Objective:To explore the damage of vestibular inner ear after Co irradiation and the relationship of vestibular apparatus injury and caspase-3, bax and bcl-2. Methods: Forty guinea pigs were randomly divided into 5 groups, including control (N) and radiation groups (Dl , D4, DM and D30). The right ear of the guinea pigs was radiated. The guinea pigs were sacrificed on

  7. Study on the possibility of using a 60 Co therapeutical unity in Intensity Modulated Radiotherapy (IMRT)

    With the increasing advances in complex treatment techniques, there is a tendency to obtain more sophisticated equipment to deliver the dose. The use of 3D conformal radiotherapy is now routine in many radiotherapy facilities as well as the utilization of intensity modulated radiotherapy (IMRT). Both are usually implemented using linear accelerators equipped with multi leaves collimators, which create the conformity and the fluence distributions required. However, the complexity of increasingly sophisticated equipment, such as linear accelerators, requires a frequent quality control of their operation, as well as a detailed and constant maintenance. Even carrying out these procedures, the accelerators may present technical problems interrupting for a long time a treatment using the IMRT technique. Despite the clear practical and technological advantages that linear accelerators have on 60Co irradiators, these devices occupy an important place in radiotherapy, mainly due to the low cost of equipment installation and maintenance when compared to those required by accelerators. Many radiotherapy facilities that work with IMRT have tele therapeutic isocentric 60Co units. In principle, such equipment would be able to be used for treatment with IMRT using compensating blocks to modulate the beam. This study investigates this possibility and shows that it is feasible. The comparison of treatment plans of a head-and-neck cancer and other of a cancer of the central nervous system, based on a 60Co irradiator and a Linac 2300 C/D, presented advantages for the 60Co irradiator. Furthermore; the delivery of dose obtained with the two systems showed themselves equivalent when compared to their respective plans. (author)

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

    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.

  9. Effects of 60Co-γ-ray and cyclophosphamide on the contents of monoamine neurotransmitters in hypothalamus of rats

    The model of rats irradiated by 60Co-γ-ray(60Co) or injected by cyclophosphamide (Cy) was studied. It was found that the contents of monoamine neurotransmitters change greatly in the hypothalamus in both kinds of model. The contents of noradrenaline (NA) and dopamine (DA), and the ratio of DA to DOPAC increased significantly in hypothalamus of rats irradiated by 60Co. The contents of NA and the ratio of 5-hydroxyamine (5-HT) to 5-hychoxyindole acetic acid (5-HIAA) decreased markedly in lamus of rats injected by Cy. The author thinks that there is a certain relation between the monoamine neurotransmitters and the activity of methylation of NA and monoamine oxidase

  10. HeLa cell tumor response to 60Co, Cs-137, Cf-252 radiations and cisplatin chemotherapy in nude mice

    HeLa cells were implanted into athymic nude mice from tissue culture and solid tumors established (HeLa cell tumor or HCT). Large cell numbers of 1 X 107 were required to obtain consistent and progressive growth, and tumor growth followed a Gompertzian mode. Irradiation studies were carried out using acute Cobalt-60 (60Co), low-dose-rate (LDR) Cs-137 and LDR Cf-252. Cf-252, a neutron-emitting radioisotope, produced an immediate tumor shrinkage and regression response after a dose of 279 cGy. Acute 60Co or LDR Cs-137 irradiation with 1000 cGy had little effect on the HCT. After a dose of 2000 cGy of 60Co radiation tumor shrinkage followed a latent period of approximately 5 days. Cisplatin had no effect on the HCT in nude mice in stationary or late exponential growth

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

    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 60Co 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. - Highlights: • The absorbed doses in the bladder, rectum and thyroid were measured. • Measurements were done during prostate treatment with a 60Co unit. • TLD100s in a water phantom were used. • The effective doses were also estimated

  12. A comparison of pdd for 60Co teletherapy units

    Although BJR supplement No 17 provides TAR and PDD tables for 60Co gamma rays, due to inherent differences hat exists among individual teletherapy machine and their source it is essential to measure TAR and PDD that are applicable for user's teletherapy unit. TAR and PDD values for different field sizes at 80 cm SSD, open field, gantry angle 0o, collimator angle 0o were determined in CIRUS 60Co teletherapy unit by ionization chamber NE2570/1B Farmer type. PDD for a standard field size 10 10 cm2, open field, gantry angle 0o,Collimate angle 0o were determined in MEDNIF FYC 2600H 60Co teletherapy unit by using ionization chamber RT101. That experimentally measured PDD values for both units were compared with published values in BJR supplement No 17. The experimentally measured values for CIRUS 60Co showed up to 0.8% deviation at maximum and that for MEDNIF 60Co showed up to 4.5% deviation at maximum. This study investigated the discrepancy between the BJR values and experimentally determined values for two teletherapy units in Nepal

  13. Concentration of 60Co by marine organisms through sediments

    Uptake of 60Co absorbed on sea sands by benthic marine organisms was observed in laboratory experiments, since the radioactive cobalt released from nuclear power plants or other establishments into coastal seawater trends to be absorbed on sea sediments and also various kinds of marine organisms live in bottom sediments. Few kinds of flatfishes (Limanda spp.) and shrimp (Trachypenaeus curvirostris) were reared in aquariums contained seawater and sea sands which were highly contaminated with 60Co previously, and whole body retention and distribution of radioactivity were measured on the organisms taken up from the aquariums occasionally by a scintillation counter. Uptake of 60Co from ingested sea sands was also observed on the flatfishes administrating the contaminated sands orally. Concentration of 60Co by the flatfishes reared in the sands was not significant while the shrimp showed high retention of the radioactivity. The food habit of shrimp which usually feeds on organic detritus with other small benthic organisms is different from that of flatfishes, one of the carnivorous, and considered to bring the difference on the pathway of radionuclides concentration. Assimilation of 60Co via the digestive tract of flatfishes through the sands was estimated as about 10 per cent of the administrated radioactivity. (auth.)

  14. On the Spirulina platensis - 60 Co2+ bioaccumulation system

    Radiochemical studies, IR spectrometry and electron microscopy studies have been carried out with the purpose of establishing the mechanisms involved in the bioaccumulation of 60 Co2+ in the blue alga Spirulina platensis. By measuring the radioactivity it was determined that, without ionic competition, an one week old culture of Spirulina platensis can retain up to 65% of the 60 Co2+ ions from a slightly radioactive solution. Sodium carbonate is involved in the mechanism of the bioaccumulation of these β + γ - radiocations (a phenomenon evidenced by IR spectrometry). Electronic microscopy studies point out that the compounds resulted from the interaction between the exopolysaccharides and 60 Co2+ disperse in the solution. Thus, even though the radiocobalt is completely blocked up in complex compounds, it is not completely retained on the surface and inside of the alga. (authors)

  15. Preparation of low molecular weight chitosan by a combination of chemical treatment and 60Co gamma radiation

    A low molecular weight chitosan finds potential applications in agriculture, medicine, personal health care, cosmetics etc. Chitosan undergoes depolymerization when exposed to ionizing radiation, therefore 60 Co gamma rays or electron beam irradiation appears to be the most promising way to prepare a low molecular weight chitosan

  16. Dosimetric evaluation of Radiotherapy units wit 60Co

    The SSDL network of the IAEA performs, every year, quality audit tests for radiotherapy services (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 60 Co radiotherapy units. (Author)

  17. Comparative analysis of 60Co intensity-modulated radiation therapy

    Fox, Christopher; Romeijn, H. Edwin; Lynch, Bart; Men, Chunhua; Aleman, Dionne M.; Dempsey, James F.

    2008-06-01

    In this study, we perform a scientific comparative analysis of using 60Co beams in intensity-modulated radiation therapy (IMRT). In particular, we evaluate the treatment plan quality obtained with (i) 6 MV, 18 MV and 60Co IMRT; (ii) different numbers of static multileaf collimator (MLC) delivered 60Co beams and (iii) a helical tomotherapy 60Co beam geometry. We employ a convex fluence map optimization (FMO) model, which allows for the comparison of plan quality between different beam energies and configurations for a given case. A total of 25 clinical patient cases that each contain volumetric CT studies, primary and secondary delineated targets, and contoured structures were studied: 5 head-and-neck (H&N), 5 prostate, 5 central nervous system (CNS), 5 breast and 5 lung cases. The DICOM plan data were anonymized and exported to the University of Florida optimized radiation therapy (UFORT) treatment planning system. The FMO problem was solved for each case for 5-71 equidistant beams as well as a helical geometry for H&N, prostate, CNS and lung cases, and for 3-7 equidistant beams in the upper hemisphere for breast cases, all with 6 MV, 18 MV and 60Co dose models. In all cases, 95% of the target volumes received at least the prescribed dose with clinical sparing criteria for critical organs being met for all structures that were not wholly or partially contained within the target volume. Improvements in critical organ sparing were found with an increasing number of equidistant 60Co beams, yet were marginal above 9 beams for H&N, prostate, CNS and lung. Breast cases produced similar plans for 3-7 beams. A helical 60Co beam geometry achieved similar plan quality as static plans with 11 equidistant 60Co beams. Furthermore, 18 MV plans were initially found not to provide the same target coverage as 6 MV and 60Co plans; however, adjusting the trade-offs in the optimization model allowed equivalent target coverage for 18 MV. For plans with comparable target coverage

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

    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)

  19. The data correction algorithms in 60Co train inspection system

    Because of the physical characteristics of the 60Co train inspection system and the application of high-speed data collection system based on current integral, the original images have been distorted in a certain degree. Authors investigate into the reasons why the distortion comes into being, and accordingly present the data correction algorithm

  20. Development of 60Co cargo train inspection system

    The author introduces the research and development of 60Co cargo train inspection system. With the use of radiography principle, every car image is acquired when the cargo train runs through the inspection channel. It is evaluated whether the cargo in car matches the corresponding customs declaration information with digital image processing techniques. The system has been installed in railway port at Manzhouli Customs

  1. Gamma 60 Co D L 50/30 of Biomphalaria glabrata (Say, 1818)

    The variation of resistance to 60 Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60 Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

  2. Gamma {sup 60} Co D L {sub 50/30} of Biomphalaria glabrata (Say, 1818)

    Carvalho, Elaine Barros da Costa; Melo, Ana Maria Mendonca de Albuquerque; Motta, Mauricy Alves da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    1999-12-01

    The variation of resistance to {sup 60} Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell {sup 60} Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL{sub 50/30}=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

  3. The effect of 60Co γ-rays on Con A and LPS induced lymphocytes

    The effect to 60Co γ-rays on lymphocytes induced by Con A and LPS and the relationship between these two groups of cells were investigated by means of 3H-TdR incorporation. The study showed that in vitro, Con A cells were able to promote the inducing effect of LPS to B cells. When Con A cells were irradiated by 10 Gy γ-rays, the 3H-TdR incroporation value reduced significanly and the stimulating effect of Con A cells on LPS cells disappeared. Having been irradiated by γ-rays, LPS cells were not able to be stimulated by normal Con A cells. When the groups of cells were incubated together after irradiation, the synergistic function disappeared, furthermore the suppressive effect of Con A cells on LPS cells emerged. When these two groups of cells were investigated by means of agar culture, the suppressive effect of 10 Gy-γ-rays on lymphocytes colony formation was more obvious. Tests on 8 patients who were suffering from carcinoma of nasopharynx showed that after a course of teatment with 60Co γ-rays, the incorporation value in Con A cells became much smaller, the stimulating effect of Con A cells on LPS cells disappeared. LPS cells could not be stimulated by normal Con A cells. The study demonstrated that the radiosensitivity of Con A cells was higher than that of LPS cells

  4. The effect of 60Co γ-rays on con A and LPS induced lymphocytes

    The effect of 60Co γ-rays on lymphocytes induced by Con A and LPS and the relationship between these two groups of cells were investigated by means of 3H-TdR incorporation. The study showed that in vitro, Con A cells were able to promote the inducing effect of LPS to B cells. When Con A cells were irradiated by 10 Gy γ-rays, the 3H-TdR incorporation value reduced significantly and the stimulating effect of Con A cells on LPS cells disappeared. Having been irradiated by γ-rays, LPS cells were not be able to be stimulated by normal Con A cells. When the groups of cells were incubated together after irradiation, the synergistic function disappeared, furthermore the suppressive effect of Con A cells on LPS cells emerged. When these two groups of cells were investigated by means of agar culture, the suppressive effect of 10 Gy γ-rays on lymphocytes colony formation was more obvious. Tests on 7 patients who were suffering from carcinoma of nasoparynx showed that after a course of treatment with 60Co γ-rays, the incorporation value in Con A cells became much smaller, the stimulating effect of Con A cells on LPS cells disappeared. LPS cells could not be stimulated by normal Con A cells. The study demonstrated that the radiosensitivity of Con A cells is higher than that of LPS cells

  5. Reliability of planar silicon transistors exposed to 60Co γ rays

    This report gives an account of results obtained during investigations on the reliability of silicon Planar Transistors, irradiated by the 60Co γ rays. We consider in a first part the variation of the average values of the parameters of the lots under test. Then, a more complete statistical study is carried out (distribution of the values of the parameters within the lots; research of correlations, etc. ). It is clearly stated and shown that evaluation of the degradation of the gain of transistors depends on: the conditions of measurement (voltage, current), after irradiation; the polarisation of the elements during irradiation; the origin of manufacture of the lots under test (4 manufacturers). We show then the difficulties met to predict the behaviour of the transistors under radiation stress, and attempt is made to define practical rules for design engineers. (author)

  6. Determination of the sterilizing gamma radiation dose of 60Co to ACANTHOSCELIDES OBTECTUS imagos (col. bruchidae)

    This paper relates the results of experiments dealing with irradiation of adults of Acanthoscelides obtectus (Say, 1831). The insects were irradiated with doses of 0 (control), 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 20 krad gamma radiation of a 60Co source. After irradiation, the adults were kept for observation on beans (Phaseolus vulgaris) var. Jalo, in a controlled environmen t chamber at 30 +- 10C and 70 +- 5% relative humidity. Continuous weighing at weekly intervals was done 22 times, showing, by weight loss in percent, that the sterilizing dose for adults was 10,65 krad. It could also be observed that losses of less than 0,5% occured at 9 krad. For a possible employment on commercial scale, the ideal radiation dose for bean desinfestation would be 10 krad, after which no weight loss occurrence. (Author)

  7. Effects of 60Co γ rays on the cell cycle progress of MCF-7 cells

    To investigate the effects of ionizing radiation on cell cycle progress of tumor cell lines, the human breast cancer MCF-7 cell line cultured in vitro was exposed to 60Co γ rays and the alterations in cell cycle progress after irradiation were measured by flow cytometry. The results indicated that the MCF-7 cells showed a transient S arrest continuing for about 6 h and an obvious G2 arrest continuing for about 63 h after irradiation with 5.0 Gy γ rays. S and G2 arrest culminated at 9 h and 18 h respectively after irradiation and the peak values of S and G2 arrest reached respectively 1.6 times and 6.2 times as many as normal value. The dose-effect curve examined 9 h after irradiation was quite different from that examined 18 h after irradiation. Both of the S arrest at 9 h after irradiation and the G2 arrest at 18 h after irradiation presented significant relationship with irradiation dose

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

    Erma Sulistyaningsih; Sukarti Moeljopawiro; Jarot Subandono; Wayan T. Artama

    2015-01-01

    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 recom...

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

    Purpose: To determine the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters (TLD-100) for 125I and 103Pd brachytherapy sources relative to 60Co. Methods: LiF:Mg,Ti TLDs were irradiated with low-energy brachytherapy sources and with a 60Co teletherapy source. The brachytherapy sources measured were the Best 2301 125I seed, the OncoSeed 6711 125I seed, and the Best 2335 103Pd 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 60Co 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 60Co irradiations. The measured and MC-calculated results for all irradiations were used to determine the TLD intrinsic energy dependence for 125I and 103Pd relative to 60Co. Results: The relative TLD intrinsic energy dependences (relative to 60Co) 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 125I and 103Pd sources relative to 60Co. TLD measurements of absolute dose around 125I and 103Pd brachytherapy sources should explicitly account for the relative TLD intrinsic energy dependence in order to improve dosimetric accuracy

  10. Distribution of 60Co in steel samples from Hiroshima

    This paper describes ultra low-level gamma-ray spectrometry measurements of the 60Co activity distribution inside one 52 mm and one 41 mm thick steel sample. The samples had been exposed to the Hiroshima atomic bomb and were from the Aioi bridge and the Yokogawa bridge. Both samples were measured in a recent study aiming to back up model calculation of Hiroshima dosimetry. The 60Co activity distributions found in this study support the assumptions made in the previous study. - Highlights: ► The Co-60 activity distribution within two thick steel samples from Hiroshima was measured. ► Activities down to 0.1 mBq were measured using underground gamma-ray spectrometry systems. ► The distribution confirms assumptions made in previous studies. ► Further support to the Dosimetry System 02 is provided.

  11. Software program in 60Co container inspection system

    The author analyzes the features and limits of the present container inspection system in the world, and puts forward a new inspection apparatus with 60Co as radiography source and microcomputer network to complete inspecting image's acquisition, transmission, assignment, process, inspection, control and information management etc. The author emphasizes on task analysis and technical request in the system, discusses the software running environment and developing environment, the tasks logical division, and makes clear the design's idea, object and style

  12. Fabrication, qualification and calibration of 60 Co sealed sources

    Argentina produces about 5% of the worldwide production of 60 Co radioisotope (3,000,000 of Ci/year) whose main application is the radio sterilization of disposable medical consumables, the radiating therapy, and the food preservation for human consumption. From 1985 to the present 56,000,000 Ci were produced. At first all the generated 60 Co was exported in bulk to the sealed sources producers, but now the local production of sources has been consolidated and 100% of the 60 Co is used to manufacture sealed sources. That is a successful production of around 400 sealed sources, 70% of which have been made during the last three years. Mainly 95% of the sealed sources for industrial applications were exported to the United States, Europe, Japan and China. These countries are the main importation centers. The local and regional markets are the most important users of the sources for x-ray radiography. At present 8% of the total sources that were produced are used as x-ray sources. The present work describes the development of the sequence of manufacture of simple and double encapsulated radioactive sources, which includes the in-process inspection, the certification of the sealed sources according the designation E66646 (5,7) of the ISO 2919:1999(E) standard and a statistical quality control analysis of the penetration of the seam weld of the end caps. (author)

  13. Comparison of treatment in soybean grains between 60Co and e-beans applications

    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 60Co. 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 60Co 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 60Co 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)

  14. Onset of behavioral effects in mice exposed to 10-Gy 60Co radiation

    Maier, D.M.; Landauer, M.R.

    1990-10-01

    The effects of 10 Gray (Gy)60Co radiation on social behavior, locomotor activity, and body weight were assessed in individually housed male Swiss-Webster mice. In Experiment 1, aggressive behavior was evaluated prior to irradiation and for 7 d postirradiation by placing an untreated intruder in the irradiated or sham-irradiated resident's home cage for 5 min. Offensive aggressive behavior was not affected significantly by radiation until day 7 postirradiation, when attack latency increased, the frequency and duration of fighting decreased, and the frequency of bites, lunges, and chases decreased. Untreated intruder mice paired with irradiated resident mice showed a decrease in the duration of defensive upright postures, squeaks, and escapes on day 7 postirradiation. In Experiment 2, locomotor activity and body weight were monitored for 7 d postirradiation. Body weight was decreased in irradiated mice beginning 4 d postirradiation. Locomotor activity was suppressed in irradiated animals 90 min after irradiation and remained depressed throughout the 7-d testing period.

  15. Effects of 60Co γ-rays on PWM and LPS induced lymphocytes

    The relationship between lymphocytes induced by PWM and LPS was investigated by means of 3H-TdR and 14C-UR incorporation. The study showed that in votro, PWM-induced cells were able to promote the stimulating effect of LPS to B lymphocyte. The stimulating effect of PWM-induced cells was obviously weakened after PWM cells being irradiated with γ-rays. When PWM-induced cells and LPS-induced cells were incubated together, with one kind of cells exposed to 60Co γ-rays, incorporation value of 3H-TdR became much smaller and the synergetic function disappeared, especially, when PWM-induced cells were irradiated. For patients suffering from carcinoma of nasopharynx, when treated with 60Co γ-rays, the incorporation value in LPS-induced cells approached normal level, while the incorporation value in PWM-induced cells reduced significantly and the stimulating effect of PWM-induced cells on LPS-induced cells became much weaker. The fact described above demonstrated that PWM-induced cells have the function of T-helper cells and play a more important role in the synergy than LPS induced cells

  16. Effect of 60Co γ-rays on PWM and LPS induced lymphocytes

    The relationship between lymphocytes induced by PWM (pokeweed mitogen) and LPS (lipopolysaccharide) was investigated by means of 3H-TdR incorporation. The study showed that, in vitro, PWM-induced cells were able to promote the stimulating effect of LPS to B lymphocytes. The stimulating effect of PWM-induced cells was obviously weakened after PWM cells being irradiated with γ-rays. When PWM-induced cells and LPS-induced cells were incubated together, with one kind of cells exposed to 60Co γ-ray, incorporation value of 3H-TdR became much smaller and the synergetic function disappeared, especially, when PWM-induced cells were irradiated. For patients suffering from carcinoma of nasopharynx, while treated with 60Co γ-rays, the incorporation value in LPS-induced cells approached normal level, meanwhile, the incorporation value in PEM-induced cells reduced significantly and the stimulating effect of PWM-induced cells on LPS-induced cells became much weaker. The facts described above demonstrated that PWM-induced cells have the function of T-helper cells and play more important role in the synergy than LPS-induced cells

  17. Radiation esophagitis in the opossum: radioprotection with indomethacin. [/sup 60/Co

    Northway, M.G.; Libshitz, H.I.; Osborne, B.M.; Feldman, M.S.; Mamel, J.J.; West, J.H.; Szwarc, I.A.

    1980-05-01

    Twenty-five opossums were evaluated before irradiation by fiberoptic endoscopy and air-contrast barium esophagram examination. All animals received 2250 rad /sup 60/Co-irradiated in a single exposure to the entire esophagus and lower exophageal sphincter. Animals received treatment with indomethacin. Acute esophagitis occurred 7 to 10 days postirradiation in control animals and was characterized by erythema, ulceration, and sloughing of esophageal mucosa as determined by air-contrast barium esophagram, endoscopy, and histology. Prostaglandin-treated animals showed more severe evidence of esophagitis than control animals. Indomethacin-treated animals showed no signs or only mild esophagitis posttreatment. It is concluded that indomethacin treatment may significantly reduce the severity of radiation esophagitis perhaps by blockade of prostaglandin synthesis.

  18. Treatment of pituitaary dependent cushing's syndrome with closed stereotactic radiosurgery by means of 60Co gamma radiation

    Four patients with pituitary dependent Cushing's syndrome treated with external irradiation to the pituitary using 60Co gamma irradiation given with a stereotactic technique. The size of the sella turcica was normal or slightly enlarged in all patients. The doses given varied between 7000 and 10000 rad, and the observation time ranged between 14 and 20 months. Three of the patients showed complete clinical remission and one marked improvement. One patient developed ACTH insufficiency, while none developed insufficient secretion of other pituitary hormones. No complications of the irradiation were observed. (author)

  19. Radioprotective effects of sodium tungstate on hematopoietic injury by exposure to 60Co γ-rays in Wistar rats

    Radioprotective effects of sodium tungstate (ST) on 60Co γ-ray induced decrease in hematocrit value and in survival rate in Wistar strain male rats were examined. A long term administration of ST (less than 150 mg/kg body weight/day) for 60-300 day had no significant effects on body and organs weights and survival days. The LD50/60 in 20 weeks old rats was 220 mg/kg body weight/day. Daily administration of 38, 75 or 150 mg from 7 days before and after irradiation to 60 days significantly mitigated the decrease in hematocrit values, especially at 23 days after irradiation (P60Co γ-rays significantly. The dose-reduction factor for survival of 38 mg ST administered rats was 1.14. (author)

  20. Sorption of 60 Co in natural zeolite (clinoptilolite)

    A Mexican zeolite (clinoptilolite) from Taxco, Guerrero, was partially stabilized with sodium cations. Radioactive Cobalt (60 Co) was used to study the Co 2+ sorption in the stabilized zeolite (Na+). It was found that sorption in general does not favour the diffusion of cobalt between framework, it explains because of it is a natural zeolite and its composition heterogeneous decrease its exchange capacity by the generated competence to the existence other type of exchange ions. The cobalt retention reached the highest level, around 0.408 m eq Co2+ /g in the Na-Clinoptilolite. The crystallinity of the aluminosilicates was maintained during experiments, it was verified by XRD patterns. (Author)

  1. Determination of 60Co sorption in natural clinoptilolite

    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 CoCl2 solution marked with 60 Co at p H 6.5 in different contact times. It was observed a maximum sorption of 0.408 m eq Co+2/g mineral, from 0.314 m eq Co+2/g mineral correspond at ion exchange. (Author)

  2. 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)

    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

  3. Study on the possibility of using a {sup 60} Co therapeutical unity in Intensity Modulated Radiotherapy (IMRT); Estudo sobre a possibilidade do uso de uma unidade terapeutica de {sup 60}Co em IMRT

    Dantas, Samuel Cesar

    2009-06-15

    With the increasing advances in complex treatment techniques, there is a tendency to obtain more sophisticated equipment to deliver the dose. The use of 3D conformal radiotherapy is now routine in many radiotherapy facilities as well as the utilization of intensity modulated radiotherapy (IMRT). Both are usually implemented using linear accelerators equipped with multi leaves collimators, which create the conformity and the fluence distributions required. However, the complexity of increasingly sophisticated equipment, such as linear accelerators, requires a frequent quality control of their operation, as well as a detailed and constant maintenance. Even carrying out these procedures, the accelerators may present technical problems interrupting for a long time a treatment using the IMRT technique. Despite the clear practical and technological advantages that linear accelerators have on {sup 60}Co irradiators, these devices occupy an important place in radiotherapy, mainly due to the low cost of equipment installation and maintenance when compared to those required by accelerators. Many radiotherapy facilities that work with IMRT have tele therapeutic isocentric {sup 60}Co units. In principle, such equipment would be able to be used for treatment with IMRT using compensating blocks to modulate the beam. This study investigates this possibility and shows that it is feasible. The comparison of treatment plans of a head-and-neck cancer and other of a cancer of the central nervous system, based on a {sup 60}Co irradiator and a Linac 2300 C/D, presented advantages for the {sup 60}Co irradiator. Furthermore; the delivery of dose obtained with the two systems showed themselves equivalent when compared to their respective plans. (author)

  4. Polymer microcapsules prepared in inverse emulsion by 60Co γ-ray induced interfacial polymerization

    Inverse emulsion was usually applied to polymerization of hydrophilic monomers, such as acrylamide, acrylic acid, salt of acrylic acid, and N-isopropylacrylamide. However, there have been few reports of one-step synthesis hydrophobic polymer hollow spheres or microcapsules in inverse emulsion system via an interfacial polymerization approach under mild reaction conditions. The motivation of this work is to explore the formation mechanism of polymer microcapsules via γ-ray irradiation in W/O inverse emulsion system. Utilizing the strong reducing radical (OH, hydrated electron) and oxidant radical (eaq-, hydroxyl radical) produced in aqueous phase by 60Co γ-ray irradiation, two interfacial redox initiation systems were proposed and applied to the preparation of polymer microcapsules. In this work, BPO (benzoyl peroxide)-eaq- and DMA (N, N-dimethyl aniline)-OH were used to control the polymerization position at the water-oil interface. High viscosity of external oil phase, high inner phase emulsion and polymeric surfactant were employed to depress the homogeneous nuclei and enhance stability of the inverse emulsion during polymerization. A typical inverse emulsion of water : Span80: kerosene : styrene = 20ml : 2.0g :10ml/4ml (including 0.050g BPO) was irradiated to 20 kGy by 60Co γ-rays at a dose rate of 65 Gy/min. Finally, polystyrene microcapsules were synthesized successfully with an average diameter of 400 nm and shell thickness of 50 nm. The productivity of micro-capsules decreased with the increasing of styrene content due to the homogeneous nuclei. When cyclohexane was used as the oil phase, porous polymer materials can be successfully obtained. Because of the multiplicity in choosing oil-soluble monomers and substances being dissolved in the aqueous phase, this approach revealed interests in encapsulation of bioactive materials or drugs. (authors)

  5. Effect of 60Co γ-rays on the lymphocyte subsets with monoclonal antibodies

    Three kinds of monoclonal antibodies (McAb), OkT4 McAb, OkT3 McAb and HI43, were used to identify T helper (Th). T suppresser (Ts) and B lymphocytes respectively. After lympbocytes were immediately exposed to 0.1 Gy, 0.25 Gy and 4 Gy 60Co γ-rays, 200 cells were counted to obtain the percentage of immunofluorescence positive cells. The results show that when the Th, Ts and B lymphocytes were irradiated by 0.1 Gy 60Co γ-rays, their abilities to combine with McAb decreased significantly. The radiation effect was more remarkable with increasing radiation dosage. Three kinds of the immunofluorescence positive cells percentages were analysed with weighted linear regression method. The relational coefficients (r) of Th, Ts and B lymphocytes were 0.8131, 0.8832 and 0.9086. The significant tests of regression coefficient showed that the radiosensitivities of Ts and B lymphocytes were higher than that of Th lymphocytes

  6. Effect of 60 Co gamma radiation on Biomphalaria Glabrata (Mollusca, Gastropoda) embryos: mortality, malformation and hatching

    A study was carried out on the radiosensitivity of Biomphalaria glabrata embryos submitted to doses of 5, 10, 15, 20 and 25 Gy of 60 Co during the cleavage, blastula, gastrula, young trochophore and trochophore stages. Mortality, malformation and hatching were the parameters used to evaluate the damage induced by ionizing radiation. Estimated L D50 values (15 days) showed that the cleavage stage (4.3 Gy) was approximately four times more radiosensitive than the trochophore stage (17.0 Gy). Susceptibility to malformation induction was higher in the blastula, gastrula and young trochophore stages. Several types of morphogenetic malformations were observed, such as head malformations, exogastrulas, shell malformations, and embryos with everted stomodeum, with nonspecific malformations being the most frequent. The types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied. The dose of 15 Gy was sufficient to greatly reduce the number of hatching snails regardless of the embryonic stage irradiated. We conclude that the effect of 60 Co gamma radiation on B. glabrata embryos presented a specific pattern. (author)

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

    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.

  8. Study of 60Co as gamma source in backscatter gamma densitometers

    In this work the performance of backscatter gamma densitometer is studied using 60Co 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 60Co in this system. Furthermore, a comparison between 60Co and was done. The obtained results indicate that 60Co can be advantageous in this regard.

  9. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818 DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818

    Elaine Barros da Costa CARVALHO

    1999-11-01

    Full Text Available The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30 = 218.2 Gy was found greater than in cross-fecundation forms. These data point to a low radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon.A variação da resistência entre indivíduos em autofecundação e fecundação cruzada de Biomphalaria glabrata foram estudadas. Uma população de 480 moluscos foi observada durante 29 dias, distribuída em 8 grupos de caramujos isolados e 8 grupos em colônias após a exposição (30 caramujos por grupo-dose a doses crescentes de radiação gama. Foram usadas doses de 10, 20, 40, 60, 80, 160, 320 e 640 Gy de um irradiador Gamma-Cell 60Co. Dois grupos não irradiados - isolado e colônia - foram separados como controle e após a irradiação todos os caramujos voltaram para aquários onde viviam antes. A sobrevida foi estimada pela contagem diária dos animais vivos em cada grupo-dose, a partir do dia da irradiação. O resultado mostrou maior sobrevivência nos grupos isolados (DL50/30 = 218.2 Gy que nos grupos

  10. Fieldbus: technology application in a 60Co sterilization plant

    Process instrumentation was made by pressure signals in the 1940s. In the 1960s, 4-20 mA analogue signals were introduced. The development of digital processors in the 1970s sparked the use of computers to monitor and control instruments from a central point. In the 1980s smart sensors were developed and implemented in digital control, microprocessor environments. Fieldbus is a generic-term that describes a new digital communications network. The network is a digital, bi-directional, multidrop, serial-bus, and communications network used to link isolated field devices, such as controllers, transducers, actuators and sensors. Fieldbus technology may improve quality, reduce costs and increase efficiency because information is transmitted digitally without analog to digital or digital to analog converters, which also minimizes hardware errors. Fieldbus communication is based on two-wire communication, interconnecting all the components in the system. This paper introduces Fieldbus technology in a 60Co sterilization plant

  11. Retention of ingested (60)Co by a freshwater fish

    The experiment was carried out on a group of 10 carp receiving the soft tissue of previously contaminated lymnaea as food. Ingestion by carp of 45 daily rations, distributed over a 63-day period, resulted in a low retention of the radionuclide. The contamination kinetics showed that the steady state should be reached after only 225 days. The 60Co transfer factor was approximately 10−2 and the retention factor about 3.3 x 10−3. During the depuration phase, radiocobalt elimination by the carp developed in accordance with an exponential model based on the existence of two biological half-lives of 1.5 and 35 days which indicate a high Co turnover. During both phases of the experiment, urinary and branchial excretion appeared to be higher than faecal excretion

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

    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)

  13. Microbiological analysis of peach palm in natura submitted to 60Co radiation

    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 60Co multipurpose irradiator. Radiation treatment appeared to be a useful alternative to reduce microbial contamination in the samples analyzed. (author)

  14. A study on the radiative mutation on the seeds of Adzuki bean by 60Co γ ray

    The seeds of Adzuki bean were irradiated by 60Co γ ray of 0-700 Gy. The results showed that: (1) The sub-lethal dose (LD50) was 389 Gy and the early seedling leaf at M1 showed incised, chlorotic, yellow, mosaic and curly edge. The absorbed dose was related with the rate of misshaped leaf. chromosomal aberration, chromosome bridge and fragment of M1 in the tip were observed. If the seed was irradiated with 400 Gy, the rate of abnormal cell at the root was more than 10%. The relationship between pollen fertility and irradiation dose was negative correlated. When the irradiation dose was 387 Gy, the pollen fertility was 50% in the seeds of Adzuki bean. (2) The optimum irradiation dose for the seed of Adzuki bean is 400 Gy in the M1 and M2

  15. Chromosome ploidy and related enzyme activities of cymbidium goeringii rhizome treated by 60Co γ-rays

    After acute 60Co γ-rays irradiation of treated Cymbidium goeringii 'Songmei', stem tip induction, the bud induction, chromosome ploidy and cytochrome oxidase (COD), peroxidase (POD), amylase (AMY), esterase (EST) enzyme activities of rhizomes between different treatments were analyzed. Results showed that irradiation of dose above 10 Gy inhibited the bud induction and proliferation of rhizome. Low dose irradiation(≤7 Gy) induced hyperdiploid phenomenon, and all with high dose irradiation (≥10 Gy) caused hypodiploid. EST activity of Cymbidium goeringii rhizome after the treatment was higher compared to the control, POD activity and AMY activity in low dose treatment (≤ 7 Gy) were higher than that of control, while COD activity in high dose treatment (≥ 10 Gy) was higher than that of control. The results indicated that the critical dose was between in the range of 7 ∼ 10 Gy, which could be used as the optimal dose for irradiation-induced mutation of Cymbidium goeringii. (authors)

  16. Evaluation of fruit productivity and quality in Hass avocado submitted to 60Co gamma radiation

    Evaluation of productivity, postharvest behavior and fruit quality was performed on four years Hass avocado trees irradiated with 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 CO2/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)

  17. 60Co gamma radiation effect on AlGaN//AlN/GaN HEMT devices

    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. (authors)

  18. 60Co gamma radiation effect on AlGaN/AlN/GaN HEMT devices

    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.

  19. Study on change of free radicals of bamboo with 60Co γ radiation

    Bamboo samples collected in mountain areas of Fujian province were mechanically pulverized into saw dust. This breaks the covalent bonds of bamboo molecules and free radicals are formed. ESR characterization of the bamboo saw dust samples of 20, 200 and 500 mesh showed that the relative intensity of the 500 mesh saw dust was the highest, and that of the 20 mesh was the lowest(g=2.0033). After 60Co γ-ray irradiation,the intensity of free radicals increased sharply. At>100 kGy, the free radicals tended to be saturated at about 40 times of the free radicals produced mechanically. The intensity of free radicals increased exponentially with the dose below 100 kGy, and decay coefficients of the free radicals in the three samples were different. (authors)

  20. Establishment of a production line for the fabrication of mega-curie sealed 60Co sources

    In order to change the status that highly radioactive 60Co sources in China are de- pendent on imports, the fabrication technology of sealed 60Co sources was successfully developed and a mega Curie production line was established. This paper describes the hot cell facilities for the 60Co source encapsulation and quality control, the model and main technical parameters of the sealed 60Co source, the fabrication process, some key techniques in the re- search and development of the sealed 60Co source, etc. (authors)

  1. Five detector set-up for positron 1D-ACAR study of 60Co containing materials

    Design of the five detector set-up, for 1-Dimensional Angular Correlation of Annihilation Radiation (1-ACAR) study of 60Co-containing materials as well as test measurements are described. The equipment is based on simultaneous registration of a starting positron (by detection of gamma-photon with energy 1274 keV) and its annihilation with an electron in the studied material (by detection of two annihilation gamma photons with the energy 511 keV emitted mainly at the 180o-angle). Through this triple coincidence the distributing 60Co-contribution (gamma-photons with energy of 1.17 and 1.33 MeV) can be effectively separated from the annihilation spectra of irradiated reactor pressure vessel steel specimens. (author). 8 refs, 2 figs

  2. Transference kinetics of 60Co in an aquatic-terrestrial ecosystem

    The dynamics of transportation, accumulation, disappearance and distribution of 60Co in a simulated aquatic-terrestrial ecosystem was studied by isotope-tracer technique. In the aquatic system, 60Co was transported and transformed via depositing, coupling with ions and adsorption. The absorption resulted in the redistribution and accumulation of 60Co in each compartment of the system. Specific activities of 60Co in water started sharply and gently decreased. The sediment accumulated a large amount of 60Co by adsorption and ion exchange. The hornwort (Ceralophyllum demersum) could also adsorb a large amount of 60Co in a short time, because of its large specific surface area. Fish (Carassius auratus) and snail (Bellamya purificata) had a poor capacity of adsorbing 60Co. The distribution of 60Co in the fish was mainly in the viscera, and the amount of 60Co in the snail flesh was greater than that in the shell. The amount of 60Co in individual compartment in the system was changed with time. The highest specific activity of 60Co in the bean of the terrestrial system remained in the root nodule. (authors)

  3. Accumulation, Toxicity And Elimination Of 60Co In Some Aquatic Bivalves

    The present study was undertaken to evaluate the importance of some common bivalve oysters namely Caelatura teretiusculua and Caelatura companyoi as new radiobioindicators for 60Co in Egyptian aquatic environment.The uptake and accumulation of 60Co in water were followed for four weeks to evaluate the following:1-Maximum uptake as concentration factor values.2-The rate of survival of bivalves at different activity levels of 60Co to estimate its toxic effect.3-The lethal dose (LD50) of 60Co.4-The effect of ph of 60Co polluted water on survival of biota.5-The competitive effects of Zn+2 and Fe+3 with 60Co on the uptake and accumulation.6-The effect of biota weight on the uptake of 60Co.7-Elimination of the accumulated 60Co by such biota in water and in 10-4M ethylene diamine tetra acetic acid (EDTA) as chelating agent that enhance the bivalve to release the accumulated radioisotope.The results showed that 60Co was highly taken up by the investigated biota with high concentration factor values and that EDTA enhanced the decontamination of 60Co than water. It could be concluded that the investigated bivalves can be used as good radiobioindicators for pollution of water with 60Co.

  4. Influence of pH-buffer action on desorption behavior of 60Co adsorbed on sand

    In order to clarify influence of pH-buffer action of soil on desorption behavior of radionuclides absorbed on a soil, a batch type desorption experiment, in which a coastal sand adsorbed 60Co was contacted with an aqueous solution of 4, 7 or 10 in pH, was performed. When pH of the solution became higher, the desorption ratio of 60Co from the sand to the solution decreased, while the abundance ratio of non-cationic 60Co species increased. Relationship between the pH of solution and the desorption ratio of 60Co could been explained by a pH dependency of negative charge density on the sand surface. It was found that the non-cationic 60Co species in the solution was colloidal {60Co (OH)2}n, which was formed by hydrolysis of 60Co2+ at buffered pH. (author)

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

    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

  6. Mechanism of INF-γ antagonizing pulmonary fibroblast proliferation stimulated by 60Co γ-rays

    Objective: To explore the mechanism of IFN-γ antagonizing human pulmonary fibroblasts (HLF) proliferation stimulated by 60Co γ-rays. Methods: The time- and dose-effect of HLF proliferation promoted by TGF-β1 and rat serum after radiation as well as effect of IFN-γ on proliferation were observed by MTT colorimetric methods. Content of TGF-β1 in rat serum and pulmonary tissues after irradiation as well as the effect of IFN-γ on rat serum after radiation promoting HLF to synthesize TGF-β1 were determined by ELISA. Results: TGF-β1 played a role in promoting HLF proliferation. The sera of irradiated rats could promote HLF proliferation and TGF-β1 synthesis, but the effect was inhibited by IFN-γ significantly (P<0.05). The level of TGF-β1 in rat serum and lung tissues gradually increased from 1 to 4 weeks after irradiation. Conclusions: TGF-β1 is involved in the process of γ-rays stimulating HLF proliferation, while IFN-γ can inhibit HLF from synthesizing TGF-β1 and antagonize its role of promoting HLF proliferation. (authors)

  7. Protective effect of catecholestrogens against 60Co γ-ray radiation injury in mice

    When 10-week-old male BALB/c mice received whole-body irradiation with a single dose of 8 Gy 60Co γ-ray and catecholestrogen 2-hydroxyestradiol (2-OHE2) was subcutaneously injected 3 hours before and after the irradiation, 30-day survival rate of the mice was 70%, while the survival rate of the mice administered the other test samples was as follows; 2-hydroxyestrone, 20%; 2-hydroxyestriol, 20%; 4-hydroxyestradiol, 0%; 2-methoxyestrone, 0%; 2-methoxyestradiol, 0%; 2-methoxyestriol, 0%; estrone, 0%; estradiol, 5%; estriol, 0%; control, 5%. Lipid peroxide level in the liver of mice markedly increased on the 4th day after the irradiation. However, this increase in the lipid peroxide level was significantly suppressed by the administration of 2-OHE2. The radiation-induced anemia, leukopenia, and atrophy of the thymus were significantly protected by the administration of 2-OHE2. These results indicate that 2-OHE2 had a potent inhibitory effect on radiation injury. (author)

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

    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

  9. ONE CASE OF LEUKEMIA INDUCED BY 60Co ACCIDENT

    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.

  10. Determination of Absorbed Dose in Large 60-Co Fields Radiotherapy

    Radiation in radiotherapy has selective impact on ill and healthy tissue. During the therapy the healthy tissue receives certain amount of dose. Therefore dose calculations in outer radiotherapy must be accurate because too high doses produce damage in healthy tissue and too low doses cannot ensure efficient treatment of cancer cells. A requirement on accuracy in the dose calculations has lead to improvement of detectors, and development of absolute and relative dosimetry. Determination of the dose distribution with use of computer is based on data provided by the relative dosimetry. This paper compares the percentage depth doses in cubic water phantoms of various dimensions with percentage depth doses calculated with use of Mayneord factor from the experimental depth doses measured in water phantom of large dimension. Depth doses in water phantoms were calculated by the model of empirical dosimetrical functions. The calculations were based on the assumption that large 60Co photon field exceeds the phantom's limits. The experimental basis for dose calculations by the model of empirical dosimetrical functions were exposure doses measured in air and dose reduction factors because of finite phantom dimensions. Calculations were performed by fortran 90 software. It was found that the deviation of dosimetric model was small in comparison to the experimental data. (author)

  11. 60 Co 放射源运输容器屏蔽性能检测%Shielding Performance Measurements on Container for 60 Co Radioactive Sources Transport

    孙洪超; 李国强; 闫峰; 庄大杰; 孙树堂; 王学新

    2015-01-01

    工业及医疗用放射源主要包括60 Co、137 Cs、131 I、32 P、153 Sm、99 Mo、90 Sr、89 Sr等核素,射线形式有α、β、γ、中子等。本文针对运输活动中γ辐射,使用现有的60 Co放射源运输容器,开展辐射屏蔽性能检测技术研究。通过模拟计算和实验测量,得到运输容器最大装载活动情况下外部辐射水平,并对计算和实验结果进行了比较。针对放射源在屏蔽容器中安放位置发生偏移和放射源在容器中安放方式不同对容器外部的辐射水平影响进行了相关研究。研究结果可对今后完善放射性物质运输容器的辐射屏蔽性能检测提供一定的借鉴。%Some radioactive sources are often used in irradiation industry and radiothera‐py ,such as 60Co ,137Cs ,131I ,32P ,153Sm ,99Mo ,90Sr ,89Sr and so on .The radiation includeα、β、γ and n .The radiation from γ sources are the mostly concerned during the transporting of radioactive sources .The shielding performance measurements on con‐tainer for 60Co radioactive sources transport were discussed by using both Monte Carlo method simulation calculation and experiment measurement . Some important factors w as discussed w hich could affect the results of shielding performance measurements . The layout of radioactive sources had a important impact on the monitoring results of the external radiation levels of radiation sources transport container .The results affor‐ded the contribution to the improvement of the radiation monitoring and management of radioactive material transportation package .

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

    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.

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

    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

  14. Treatment of peach seeds with 60Co gamma-rays

    Peach seeds have been treated with gamma-rays during their stratification in February, March and early April to determine the optimal and lethal doses of irradiation. The latter took place at an intensity ranging between 1386 to 1750 r/min in doses of 4, 8, 12, 16, 20 and 24 kR. Untreated seeds have been used for control. The lethal dose (LD100) in irradiation stratified seeds in February and March prove to be about 16 kR. A dose between 4 to 8 kR is found most favourable for irradiation of stratified peach seeds. With raising the doses of irradiation the number of obtained plants declines. The mean height of plants also declines in the initial growth period. Some morphological changes such as shortened internodes, modified leaf shape and size, chlorophyll insufficiency and stopping of growth appear in some plants developing from irradiated seeds. (author)

  15. Characterization and performance study of high-dose 60Co gamma-ray calibration laboratory for radiation processing

    The 60Co gamma-ray irradiation facility for high absorbed dose calibration at radiation processing dose level was originally designed and constructed in JAERI. Uncertainty in absorbed dose given at JAERI was estimated by reviewing its characteristics and dosimetry performance. Dosimeter calibration equipment consists of the two plaque 60Co gamma-ray radiation sources giving different dose rate range of 5-200 Gy/h and 400 Gy/h-20 kGy/h, a dosimeter holder stage with high-reproducible positioning, a parallel-plate ionization chamber for accurate measurement of exposure-rates, and an auxiliary temperature/humidity-controlled irradiation vessel for dosimeter calibration under specific irradiation condition. The characteristics of the irradiation field and dosimetry performance are sufficient to give a known dose to working dosimeters to be calibrated for absorbed doses in the range of 0.5 Gy to 160 kGy within a reasonable operation time, 8 h, with an uncertainty of ±2.2% at a 95% confidence level. Calibration of dosimeters giving known doses by transfer dosimetry employing alanine dosimeters calibrated at JAERI is also achievable with an uncertainty of ±3.4% at a 95% confidence level. (author)

  16. Effects of 60Co γ-ray partial radiation on chromosome aberration in human peripheral blood in vitro

    Objective: To investigate the effects of 60Co γ-ray partial radiation on chromosome aberration in human peripheral blood in vitro. Methods: The samples of heparinized peripheral whole blood from 3 healthy persons were exposed to 60Co γ-rays at the doses between 0 and 8 Gy with the dose rate of 0.35 Gy/min at the temperature of 37 ℃ ,and then mixed with the unirradiated blood samples of the Microscopy was used to observe the chromosome aberration double (centromere + centromere) and the biological dose was estimated thereby. Results: The amounts of double centromere + centromere were increased along with the dose of irradiation in all groups. The estimated biological dose was higher than the 1/3 of the irradiation dose when the dose was between 0.5 to 2 Gy, and was close to the 1/3 of the irradiation dose when the dose was between 4 to 8 Gy. Conclusion: Chromosome aberration can be used as a biomarker in estimation of uneven irradiation. (authors)

  17. The radiation effect of 60Co gamma rays on polycarbonate detector

    The irradiation of polymeric materials with ionizing radiation (gamma rays, X rays, accelerated electrons, ion beams) leads to the formation of very reactive intermediates products (excited states, ions and free radicals), which result in rearrangements and/or formation of new bonds. The effects of these reactions are formation of oxidized products, grafts, scission of main chain (degradation) or cross-linking. Often the two processes (degradation - cross- linking) occur simultaneously, and the outcome of the process is determined by a competition between the reactions. Polycarbonate detectors are used as a particle track detector for neutrons and alpha particles detection. This work aims to study the ionizing radiation dose response of polycarbonate samples using spectrophotometric technique. A commercially available polycarbonate was analysed and its dosimetric characteristics were studied: radiation-induced absorption spectra, ambient light, temperature and humidity influence, pre- and post-irradiation stability, reproducibility and dose range useful response. Samples of polycarbonate (3 x 1 cm2) were irradiated with 60Co gamma radiation in free air at electronic equilibrium with absorbed doses between 1 and 95 kGy. When exposed to gamma radiation the polycarbonate detectors undergoes changes in their optical response, the colour variation is used for determining the absorbed dose. A Shimadzu UV-2101PC spectrophotometer was used for scanning the absorption spectra and measuring the optical density of film detectors irradiated with different radiation doses. Polycarbonate film detector are easy to prepare and to analyse, of good optical quality, inexpensive and of small size. The dosimetric accuracy can be affect by environmental conditions so, the detectors must be stored in appropriate conditions. The reproducibility of the detectors response can be improved by careful monitoring of optical densities before irradiation. The dose response curve presents linear

  18. The radiation effect of 60Co gamma rays on polycarbonate detector

    The irradiation of polymeric materials with ionizing radiation (gamma rays, X rays, accelerated electrons, ion beams) leads to the formation of very reactive intermediates products (excited states, ions and free radicals), which result in rearrangements and/or formation of new bonds. The effects of these reactions are formation of oxidized products, grafts, scission of main chain (degradation) or cross-linking. Often the two processes (degradation - cross- linking) occur simultaneously, and the outcome of the process is determined by a competition between the reactions. Polycarbonate detectors are used as a particle track detector for neutrons and alpha particles detection. This work aims to study the ionizing radiation dose response of polycarbonate samples using spectrophotometric technique. A commercially available polycarbonate was analysed and its dosimetric characteristics were studied: radiation-induced absorption spectra, ambient light, temperature and humidity influence, pre- and post-irradiation stability, reproducibility and dose range useful response. Samples of polycarbonate (3 x 1 cm2) were irradiated with 60Co gamma radiation in free air at electronic equilibrium with absorbed doses between 1 and 95 kGy. When exposed to gamma radiation the polycarbonate detectors undergoes changes in their optical response, the colour variation is used for determining the absorbed dose. A Shimadzu UV- 2101PC spectrophotometer was used for scanning the absorption spectra and measuring the optical density of film detectors irradiated with different radiation doses. Polycarbonate film detector are easy to prepare and to analyse, of good optical quality, inexpensive and of small size. The dosimetric accuracy can be affect by environmental conditions so, the detectors must be stored in appropriate conditions. The reproducibility of the detectors response can be improved by careful monitoring of optical densities before irradiation. The dose response curve presents linear

  19. Radiation effects of 60Co γ-rays on expression of CDKN1A mRNA in human lymphocytoblast

    Objective: To study effect of 60Co γ-rays radiation with different doses on expression of CDKN1A gene mRNA in human lymphocytoblast cultured for different time. Methods: After human lymphocytoblasts were irradiated by the 60Co γ-rays with various doses of 0, 0.2, 1, 3, 5 and 10 Gy, and cells were separately cultured for sustaining survival during 0, 4, 24, 48, 72 and 96 h. The total RNA was extracted from each sample and the real-time PCR was conducted to observe the gene CDKN1A mRNA level changes in lymphocytoblasts exposed to various radiation doses for various cultured time. Results: Expressive levels of the CDKN1A mRNA in lymphocytoblasts gradually went up with increasing radiation doses, which showed γ-rays dose dependent from 0 Gy to 5 Gy (P<0.05), and reach the peak when cells were cultured for 24 h after exposing to radiation while displayed an expressive downtrend during the later stage of cell culture. Conclusion: Increase of the CDKN1A mRNA expression level in human lymphocytoblasts after exposing to 60Co γ-rays radiation within 24 hours of culture shows a dose dependent way, which may be used to evaluate the ionizing radiation dose. (authors)

  20. Effect of gamma radiation of 60Co in the variability of chinese bean [Vigna unguiculata (l.) Walpers] en R4M4

    Selection of plants of Chinese bean coming from seed irradiated with gammas of 60Co in the generation R4M4 (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)

  1. A Study on the Characters of the Seeds of M2 Generation of Chamaecrista Freated with 60Coγ-ray Irradiation%红壤山地决明属牧草辐射后代变异趋势的研究

    徐国忠; 郑向丽; 应朝阳; 黄毅斌; 翁伯琦

    2005-01-01

    利用60Coγ射线(辐照剂量为300Gy ,剂量率为4.6875Gy)辐照豆科决明属5个牧草品种的种子,通过盆栽混合收集M1代各个品种的种子,然后进行M2代试验观察和测定,了解其变异趋势.辐射M2代试验结果表明,辐照后5个决明品种的出苗率、茎长、叶宽、地上部干重都无显著差异;冠高34721有显著增长、茎粗2219有显著增长、分枝数86134有极显著增长和92985有显著降低、叶数86134有显著增长、叶长2219有显著增长;植株的营养成分(N、P、K),全(K)2219有显著下降;植株的营养成分(氨基酸),2219氨基酸总的含量有显著下降、且17种氨基酸都表现为不同程度的下降,86134氨基酸总的含量有显著增长、且17种氨基酸都表现为不同程度的增长.

  2. TGFβ1正、反义基因转染60Co照射HELF对TGFβ1及I型前胶原mRNA表达调控影响%Gene transfection using lipid-mediated TGFβ1 sense and antisense gene expression vectors and its effects on TGFβ1 and procollagen I mRNA expression in 60Co-irradiated human embryo lung fibroblasts

    刘纯杰; 王德文; 高亚兵; 熊呈琦; 彭瑞云; 崔雪梅; 宋良文; 张兆山; 龙建银; 王会信

    2001-01-01

    Objective To investigate the effects on gene expression of 60Co-irradiated human embryo lung fibroblasts after gene transfection using lipid-mediated TGFβ1 sense and antisense gene expression vectors. Methods TGFβ1 sense and antisense gene expression vectors were transfected using a lipid-mediated method.Gene expression was analysed by RNA dot blot. Results HELFs irradiated with 5 Gy were transfected with an expression vector encoding the human TGFβ1 sense or antisense gene under control of the mouse mammary tumor virus long terminal repeat(MMTV-LTR)promotor/enhance sequence(pMAMneo-TGFβ1,or pMAMneo-anti-TGFβ1).The transfected cells elected by G418 resistance were cultured in DMEM containing dexamethasone.The chromosomal DNA and RNA were extracted.Positive reaction was showed from chromosomal DNA by a PCR method of neo-specific primers and DNA dot blot with Dig-labelling neo-specific probe.RNA dot blot analysis showed that TGFβ1 mRNA level of the cells transfected with pMAM neo-anti TGFβ1 decreased,but that of transfected with pMAM neo-TGFβ1 increased.For procollagen Ⅰ mRNA,the transfected pMAM neo-anti TGFβ1 was lower than untransfected cells and the transfected pMAM neo-TGFβ1 was higher. Conclusion After TGFβ1 sense and antisense gene transfection,TGFβ1 mRNA level of the cells transfected with TGFβ1 antisense gene decreased,but that with TGFβ1 sense gene increased.For procollagen Ⅰ mRNA,the cells transfected with TGFβ1 antisense gene was lower than untransfected cells and the cells transfected with TGFβ1 sense gene was higher than untransfected cells.%目的观察TGFβ1正、反义基因转染60Co γ射线照射的HELF后对其TGFβ1 mRNA及Ⅰ型前胶原mRNA表达调控的影响。方法采用脂质体介导法进行基因稳定转染,转染细胞经PCR,DNA dot blot鉴定和RNA dot blot分析。结果选择5 Gy照射细胞,采用Lipofect AMINE将TGFβ1正、反义基因表达载体pMAMneo-TGFβ1和pMAMneo-Anti TGFβ1

  3. Placental transfer of 60Co as a function of gestation age

    The transfer of 60Co from mother to foetus in relation to the time of gestation was examined 24 hrs after injecting 5 μCi of 60CoCl2 to the pregnant rat on 15th - 21st day of gestation. The radioactivity of foetuses, placentae as well as liver, kidney and femur of mother was determined. It was found that activity of 60Co transferred to the foetus body increased with the time of gestation. (author)

  4. Evaluation of gamma-sterilization (60Co) by RT-PCR by DHFR expression detection

    The improvement of techniques to detect pathogen agents in blood had reduced significantly the contamination mechanisms by hemocomponents in blood transfusion procedures. Ionizing radiation is a method that has presented several applications on medicine and in currently days has been showing special attention on blood banks which has been applied to avoid TA-GVHD development. DHFR is an enzyme constitutive in Plasmodium protozoa and has an important role in folate metabolism on these parasites. Detecting the expression of RNAm coder for this enzyme is possible to evaluate the viability of this parasite in blood samples. Plasmodium chabaudi AJ is a parasite that induces lethal malaria in rodents similar to human malaria In this work, the objective was to detect the presence of plasmodium protozoa in irradiated blood samples, infected experimentally, through the application of a RT-PCR using primers for the coder sequence of DHFR's mRNA. We studied doses of ionizing radiation between 0 and 75 Gy. The irradiation procedures were accomplished in Center of Radiation Technology of IPEN-CNEN in a 60Co panoramic source. Our results had demonstrated that RT-PCR is a sensible method to evaluate the viability of plasmodium in blood samples because the technique could detect low parasite burden in all tested samples. (author)

  5. Evaluation of gamma-sterilization ({sup 60}Co) by RT-PCR by DHFR expression detection

    Converso, Ana Paula G.; Andrade Junior, Heitor F. de [Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil)]. E-mail: anapaulagconverso@gmail.com; hfandrad@usp.br; Vieira, Daniel P. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil); E-mail: dperezv@usp.br

    2007-07-01

    The improvement of techniques to detect pathogen agents in blood had reduced significantly the contamination mechanisms by hemocomponents in blood transfusion procedures. Ionizing radiation is a method that has presented several applications on medicine and in currently days has been showing special attention on blood banks which has been applied to avoid TA-GVHD development. DHFR is an enzyme constitutive in Plasmodium protozoa and has an important role in folate metabolism on these parasites. Detecting the expression of RNAm coder for this enzyme is possible to evaluate the viability of this parasite in blood samples. Plasmodium chabaudi AJ is a parasite that induces lethal malaria in rodents similar to human malaria In this work, the objective was to detect the presence of plasmodium protozoa in irradiated blood samples, infected experimentally, through the application of a RT-PCR using primers for the coder sequence of DHFR's mRNA. We studied doses of ionizing radiation between 0 and 75 Gy. The irradiation procedures were accomplished in Center of Radiation Technology of IPEN-CNEN in a {sup 60}Co panoramic source. Our results had demonstrated that RT-PCR is a sensible method to evaluate the viability of plasmodium in blood samples because the technique could detect low parasite burden in all tested samples. (author)

  6. Effect of 60Co radiation-induced grafting of methyl methacrylate on mechanical properties of bamboo

    In order to investigate the effect of radiation grafting on mechanical properties of bamboo, the original and carbonized bamboo soaked with monomer MMA were radiation grafted by 60Co γ rays with the doses of 60-220 kGy. The results showed that compared with original blanks, treated with MMA and irradiated with the dose of 180 kGy the specific gravity, bending strength modulus of elasticity of original bamboo increased by 6.7%, 4.4%, and 28%, meanwhile its oven-dried radial, tangential and volumetric shrinkage decreased by 38.9%, 47.4%, and 32.9%, respectively. What is more, treated with MMA and irradiated with the doses of 140 kGy the specific gravity and modulus of elasticity of carbonized bamboo increased by 6.8% and 20%, while its oven-dried radial, tangential, volumetric shrinkage decreased by 11%, 4.6% and 12%, respectively. The study reveals that mechanical properties of original and carbonized bamboo can be enhanced by radiation grafting copolymerization with suitable absorbed doses, which may be valuable for the further research of developing new bamboo plastic composites. (authors)

  7. Change of free radicals and chemical structure of Moso bamboo with 60Co γ radiation

    After 60Co γ radiation, absolutely dry bamboo powder produced free radicals and its chemical composition and structure changed. Electron spin resonance (ESR) and X-ray photoelectron spectroscopy (XPS) techniques were used to measure the spectrum of the free radicals and X-ray photoelectron spectroscopy of the γ-ray radiated bamboo powder. The test results reveal that when the spectral splitting factor (g) of the bamboo free radicals is 2.0033, and the intensity of free radicals increase with the absorbed dosage of irradiation according to exponential law. After irradiation of 200 kGy, the O/C atomic number ratio in the bamboo surface increases slightly, C-C and C-H content increases, C-O and C=O content decreases, and -O-C=O content increases to 1.5 times over that of the original, which indicates some oxygen-containing functional groups occur and oxidation state of carbon increases in the bamboo surface. (authors)

  8. Bioaccumulation and elimination of 60 Co and 137 Cs by Anomalocardia brasiliana (Gmelin, 1791) (Mollusca bivalvia). Remobilization of 60 Co, retained in marine sediment by microbial activity

    It was studied the capacity of a bi valve mollusc Anomalocardia brasiliana, which lives in the local bottom sediment, to remobilize 60 Co previously sorbed in the sediment. Laboratory experiments demonstrated that the transference of 60 Co from the sediment to the animal was insignificant (bioaccumulation factor (BF) of the order of 10-3). At the same time, the capacity of microorganisms, present in the bottom sediment, to remobilize 60 Co was studied. The results showed that this via of transference was important, considering the much greater microorganism biomass in relation to the biomass of bentonic organisms, as a whole. For 137 Cs the determined BF from water to the animal was 2.2. and, as in the case of 60 Co, the soft tissues concentrated more 137 Cs than shell. Remaining viscera showed the highest BFs. In another series of experiments, the loss of 60 Co or 137 Cs, previously accumulated by A. brasiliana, was followed in aquaria with or without sediment and the respective biological half-lives were calculated. Soft tissues retained 60 Co longer (biological half-life = 117 days) than shells, whereas for 137 Cs the opposite was observed and shells showed a biological half life of 38.5 days. The low values of 60 Co and 137 Cs BFS do not allow to classify A. brasiliana as good biological indicator for pollution by there radionuclides. However since A brasiliana is consumed by the local population and is commercialized to other areas, it was recommended that its contamination by 60 Co or 137 Cs should be monitored. (author)

  9. Studies on the transportation dynamics of 60Co in simulated ecosystem

    The isotope tracer techniques were applied to study the transportation, accumulation and distribution of 60Co in the pot-cultivated tomato-soil, aquatic and terrestrial ecosystems. Based on the principle of tracer dynamic compartment models, the mathematical formulae were established via computer simulation to describe the 60Co behavior patterns in ecosystems and thus provided some basic information for elucidating the behavior of 60Co in the environment. The results are as follows: (1) When 60Co was introduced into the tomato-soil system, 60Co was transported and accumulated in the soil and adsorbed by tomato root quickly, then transported to the above-ground plant. (2) The behavior patterns of 60Co in the tomato-soil system could be described using the opened two-compartment model. (3) When 60Co was introduced into aquatic system in the form of 60Co-CoCl2, it was transported and transformed via deposit, complexation with other ions, adsorption and absorption by aquatic living things and led to the distribution and accumulation in individual part of the living things. (4) The behavior pattern of 60Co in the aquatic-terrestrial ecosystem could be described by using opened five-compartment model

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

    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)

  11. Use of 60Co panoramic source in the induction of oral mucositis in rats

    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 60Co 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)

  12. INCASoy-36: soybean variety obtained in Cuba after the induction of mutations with 60Co gamma rays

    INCASoy-36 variety was obtained after irradiating seeds from INCASoy-15 at doses of 240 Gy 60Co gamma rays. This variety is adapted to summer and winter seedings; however, it can also be used in spring. Besides, its yields can reach up to 3,5-4,0 t.ha-1 grains in summer and spring seedings. It is tolerant to the main pests and diseases; it is especially resistant to Meloidogyne incognita attacks. During the adverse spring season, seeds have been damage tolerant. It can assure high productions with low inputs; therefore, it is feasible to Cuban agriculture. (Author)

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

    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.

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

    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.

  15. Study on the grafting of N-vinypyrrolidone onto xanthan gum by 60Co γ-irradiation and properties of the grafted copolymer%黄原胶辐射接枝N-乙烯基吡咯烷酮及其物性研究

    李咏富; 李彦杰; 哈益明; 王锋

    2011-01-01

    Simultaneous radiation grafting method (60Co γ-rays as the radiation source) was used to prepare xanthan gum-graft-N-vinypyrrolidone (XG-g-NVP), and the influence factors of the grafting degree was preliminarily studied. The suucture of the grafted copolymer was characterized by the Fourier-transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA), and the solution viscosity properties of the grafted copolymer in low grafting rate were studied by rheometer. The results show that the grafting rate increases with absorbed dose and gradually achieve to the balance. The grafting rate reaches maximum when the xanthan gum concentration is 10 g/L or the mass ratio is 10:1 meanwhile the other two factors are in a certain experimental value range. FT-IR figure shows that the grafting reaction occurs in NVP vinyl part and lactam structure is retained. Thermo-gravimetric analysis shows that XG-g-NVP enhanced thermal stability of xanthan gum. The properties of XG-g-NVP solution show that grafting helps to enhance the performance of resisting high temperature and shear strength.%采用共辐射法制备了黄原胶-N-乙烯基吡咯烷酮接枝共聚物(XG-g-NVP).研究表明在黄原胶浓度及XG/NVP质量比一定的情况下,接枝率随吸收剂量的增加而增加,并逐步达到平衡:在吸收剂量和质量比一定时,接枝率住浓度为10g/L达到最大;在吸收剂量和黄原胶浓度一定时,接枝率在质量比为10:1达到最大值.红外光谱研究表明接枝反应发生在NVP乙烯基部位,接枝共聚物保留了NVP的内酰胺结构;热重分析表明接枝共聚物的热稳定性得到了增强.接枝共聚物在低接枝率下溶液粘性特征的流变分析表明,其抗高温、抗剪切的能力得到了提高.

  16. Investigations on Pasteurization of Cold Marinades by 60Co Gamma Rays

    Marinated herring fillets are a fish product matured under the action of acetic acid and salt and marketed in a spiced brine containing about 3% salt and acetic acid (pH 4). Since the usual addition of the preservative hexamethylene-tetramine has been restricted to a limited period of time by the new German food law, investigations were made on pasteurization by means of ionizing rays, as a new method of preservation without the addition of other preservatives. Decay of this food product was caused by heterofermentative lactic-acid bacteria, which decarboxy- lated the amino acids set free from the protein; the decay was a result of carbon dioxide bombardment. The marinades were packed into flat tins holding about 125 g, and exposed to 60Co gamma rays from an under-water source, while being cooled. The shelf life of the tinned marinades was extended by the irradiation. The period up to bombardment at 15°C was three times as long as usual in cases of irradiation with 155 krad. The critical number of 1 million germs per ml at 15°C was also reached after a period three times as long as usual upon irradiation with 160 krad. The LD99 of three isolated strains of lactic-acid bacteria irradiated in a salt-peptone solution was 113, 165 and 144 krad, respectively. Since at 15°C the growth of the germs is retarded, while at 20°C it is practically unrestrained, the period of durability at a storage temperature of 18°C could only be doubled by irradiation with 280 krad. The organoleptic tests were based on preference analyses by means of the nine-step Hedonic scale, and on difference tests (triangle test) and were performed by a paneli At 70 kràd the taste is still acceptable at 140 krad there is a distinct taste of rays and at 280 krad the taste is disagreeable. A distinct improvement in taste is achieved by irradiation at low temperatures (-30°C) and by the addition of ascorbic acid, sorbitol and spices. The experiments are being continued. (author)

  17. Effects of γ (60Co) and β (90Sr) radiations in Chinese hamster ovarian cells (CHO-K1): induction of micronuclei and cell death

    Among various types of ionising radiation, the beta emitter radionuclides are involved in many sectors of human activity, such as nuclear medicine, nuclear industries and biomedicine, with a consequent increased risk of accidental, occupational or therapeutic exposure. Despite their recognized importance, there is little information about the effect of beta particles at the cellular level when compared to other types of ionizing radiation. Thus, the objective of the present study was to evaluate the genotoxic and cytotoxic effects of 90Sr, a pure, highly energetic beta source, on CHO-K1 cells and to compare them with data obtained with 60Co. CHO-K1 cells irradiated with different doses (1.0, 2.5, 5.0, 7.5 Gy) of 60Co (0.34 Gy.min-1) and 90Sr (0.23 Gy.min-1) were processed for analysis of clonogenic death, induction of micronuclei (MN) and necrotic and apoptotic death. The survival curves obtained for both types of radiation were better fitted by the linear-quadratic model and were similar. However, the cytogenetic results showed that both the proportion of micronucleated cells and the magnitude of radioinduced lesions demonstrated by the analysis of MN distribution were significantly higher in cells irradiated with 60Co than in cells irradiated with 90Sr, whereas 90Sr was more damaging than 60Co in terms of cell death induction. Necrosis was the major type of death observed in CHO-K1 cells. The data obtained suggest that the low incidence of micronucleated cells after exposure to 90Sr may be a consequence of selective elimination of severely damaged cells from the population by the necrotic process at a higher rate than observed with 60Co exposure. The data obtained also demonstrated the need to use several parameters for a better estimate of cellular sensitivity to the action of genotoxic agents, which would be important in terms of radiobiology, oncology and therapeutics. (author)

  18. The effect of 60Co-γ ray on fertilized eggs and growing change in chicken

    The fertilized eggs were stimulated by 60Co-γ ray of different doses. The experimental results show that the rate of hatching of different fertilized eggs reaches the maximum when the dose of 60Co-γ ray is 300rad. And, the higher the dose of 60Co-γ ray is used, the lower the rate of breeding and hatching are obtained. It is concluded that it is beneficial to growing of cock and the fertilized eggs are stimulated by the 60Co-γ ray of low doses. However, the growing of hen is inhibited and eggs are early produced with the low dose treatment of 60Co-γ ray

  19. Aspects of the immune response against proteic antigens submitted to the effects of {sup 60}Co gamma radiation; Aspectos da resposta imune frente a antigenos proteicos irradiados com {sup 60}Co

    Alves, Janaina Baptista. E-mail: janabap@gmail.com

    2004-07-01

    Considering the effects of gamma radiation on proteins and the capacity of the immune system to recognize modified macromolecules, we decided to evaluate some immunological aspects of B10.PL mice exposed to native or irradiated ovalbumin and bothrops toxin-1 (BthTx-1). In order to evaluate possible structural modifications of the molecules after being irradiated ({sup 60}Co gamma rays), bothrops toxin-1 was analysed by electrophoresis, while ovalbumin was submitted to analytical size exclusion chromatography. The toxin was also analysed by ESI-mass spectrometry. Our results indicate that radiation promoted modifications on both the molecules. Aiming to compare the toxicity of the native and irradiated forms of the toxin, an in vitro cytotoxicity assay, using CHO cells, was performed. According to our results, the modified toxin was 5 folds less toxic than its native counterpart. Sera of animals immunized with the native and irradiated proteins were analyzed in order to evaluate levels of IgG, as well as to quantify specific isotopes. While the native proteins induced a predominant Th2 response, the irradiated molecules apparently promoted a switch towards a Th1 pattern. We also performed a cell proliferation assay with splenocytes from mice immunized with either the native or the irradiated proteins, cultured in the presence of the antigens. Our results indicate that both the forms of the proteins induced a similar proliferative response. These data indicate a potential use of detoxified proteins as antigens for immunization. (author)

  20. Serum asparate aminotransferase levels following cadmium and/or 60Co radiation

    A total of 216 young adult male Sprague‐Dawley rats were used. Animals were injected intraperitoneally (IP) every 3 days for 29 days for a total of 9 injections with 0, 1.0, or 2.5 mg Cd/kg body wt. Twenty‐four hrs after the last Cd injection (day 30), each animal was subjected to an acute sublethal total‐body exposure of 0, 3.62 or 5.43 gray of gamma (60Co) radiation at a dose rate of 3.04 gray/min. Eight rats from each of the 9 groups were sacrificed by cardiac exsanguination on post‐irradiation day 1, 7, or 21. A significant high‐dose cadmium‐induced increase in AST enzyme was observed at days 1 and 7; however, by day 21 levels had returned to normal. The results suggest that high‐dose cadmium increases were dose and time‐dependent. No significant differences in AST values were observed between radiation only groups, days, or doses. However, significant dose‐related differences were observed between high‐dose cadmium and means, as well as between high and low‐dose cadmium doses at days 1, 7, and 21. When the co‐insult was used, significant differences were seen between the high cadmium‐high radiation group and the mean at day one

  1. Some gamma radiation (60Co) effects on Chrysomya megacephala (Fabricius, 1794) (Diptira-Calliphoridae)

    The effect of different gama radiation (60Co) doses on Chrysomya megcephala (Fabricius) have been studied under laboratory conditions, in the Entomology Section of Centro de Energia Nuclear na Agricultura (CENA-USP), Piracicaba, SP, Brasil. The insects were collected close to sucking animals brooding areas, identified and reared on artificial diet, being kept in a temperature (26 +- 20C) and humidity (66 +- 9%) controlled room, with 12L:12D photopheriod. A Gammabeam type 650 Cobalt-60 gamma irradiation source was used, with 28, 196x1010 Bq activity at the beginning of the experiment. The pupae were submitted to increasing gamma radiation doses. To determine lethal doses, treatments were carried out at four different ages and to determine the sterilizing doses two-three day pupae were used. It was noted pupae radiosensitivity decreased with age, LD50 varying from 14 - 513 Gy. The sterilizing dose for males was 40 Gy and for females 30 Gy. During the individuals life cycle, it was noted that there was a decrease in life expectancy (exo) of adults when the gamma radiation dose was increased. Treated males were more sensitive than females (Crossed with ''normals''), there occurring a marked reduction in the number of eggs and their viability when the used gamma radiation dose was increased. (author)

  2. Modification of polyethersulfone films by grafting hydrophilic monomers with 60Co γ-rays

    Polyethersulfone (PES), with its high strength, high temperature resistance, corrosion- resistance, oxidation resistance and applicability under wide pH range, is used extensively as ultrafiltration and nanofiltration membrane. However, PES membranes foul easily in such an application because of hydrophobic nature of PES raw materials. Improving the hydrophilicity of PES by grafting hydrophilic monomers onto it is of potential to solve the problem. At present, common approaches to improve hydrophilicity of PES membranes are UV grafting modification, plasma modification, and chemical modification, whereas grafting and modifying PES films by 60Co γ-rays has rarely been reported. Studies have been carried out in our laboratory to graft hydrophilic monomers onto PES membranes directly or PES powders via simultaneous radiation grafting with the rays. Acrylic acid, methyl acrylic acid or acrylamide was used to study effects of the monomer concentration, irradiation dose and dose rate, solvent, inhibitor and pH of the grafting solution on the degree of grafting. The results showed that hydrophilicity of all the PES membranes could be improved, with the extent of improvement being dependent on the grafting conditions. (authors)

  3. Changes in membrane receptors of B and T human lymphocytes exposed to 60Co gamma rays

    The present report describes the effect of 50 to 2500 rad of 60Co gamma rays on the membrane receptors of B and T lymphocytes. Surface membrane immunoglobulins and Fc receptors were used as markers for B cells, while the formation of rosettes with sheep red blood cells was used as a marker for T cells. The effect of radiation is expressed as the percentage of viable cells that bear membrane receptors. The radiation effects were studied after 2, 24, 36 hr of culture. For B lymphocytes no reduction in SmIg and Fc receptors was seen 2 hr after radiation, whereas a dose-related reduction was observed after 24 and 36 hr. A dose-related inhibition of the ''capping'' of SmIg was observed. For T lymphocytes a reduction of E rosette formation was seen starting 2 hr after irradiation. Electron microscopy of separated B and T cells showed a higher sensitivity of T cells as well as a different structural arrangement of the chromatin as a consequence of radiation damage. These data suggest differentiated behavior of B and T lymphocyte membrane receptors after exposure to radiation

  4. Effects of 60Co gamma radiation on defense function of human polymorphonuclear leukocytes

    The effects of radiation on defense function of polymorphonuclear leukocytes (PMN) were studied following irradiation with 60Co γ radiation (30 - 3,000 rad) using PMN separated from the peripheral blood of healthy volunteers. The migration distances for all three measures of chemotaxis to fMet-Leu-Phe (10-8 M), chemokinesis induced by fMet-Leu-Phe, and random migration tended to decrease with increasing dose, showing 0.0054 μm/rad (p -5 M) in conjunction with cytochalasin B (CB, 5 μg/ml) there was a significant dose trend, showing the dose effects of decreasing 0.0022 % release/rad for BGL and 0.0030 % release/rad for LYZ with increasing dose. In superoxide anion (O2-) production, a slight and marginally significant linear dose trend was found. These results suggest that the defense function of PMN is not so resistant to radiation as predicted from the fact that PMN in the peripheral blood are differentiated and mature. It is thought that radiation inflicts substantially harmful effects on the defense function of peripheral PMN. (author)

  5. The effect of 60Co-γ ray on the culture cell of Leymus chinensis

    The chromosomal variation and the growth and differentiation of the calli of Leymus chinensis irradiated by 60Co-γ rays at different dose and dose rate were investigated. It was shown that γ-rays in the range of 30∼100 Gy induced a lot of structural variations of chromosome, such as fragmentation, ring formation etc. and led to chromosomal elimination and inhibition of mitosis of the cells. The rate of chromosomal variation and the degree of inhibition in growth and differentiation of the callus were in relation to the dose and dose rate of γ-rays. The sensitivity of the cell to γ-rays is depended on the time of subculture. After two-day's subculture the calli were most sensitive. The results provide the cytological evidence of the effect of γ-rays on the cultured cell of Leymus chinensis and may be valuable for asymmetrical cell hybridization of L. chinensis, which plays a role as a donor

  6. 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}

    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)

  7. Evaluation of 60Co radiation effect in the survival of different mouse strains. Radiomodifiers and celular response

    The radiomodifier capacity of proteose-peptone (PP), imidazole derivatives such as azomycin and levamisole against an 8 or 9 Gy single dose of 60Co irradiation of mice from IPEN animal house was evaluated, being the biological responses compared with other mouse strains. It is concluded that PP, azomycin and PP + azomycin behaved as radioprotectors, while lavamisole appeared as a radiossensitizer. The various strains showed differences in their survival indexes. The changes in body weight curves of mice from all the experiments were followed during 30 days. Qualitative and quantitative analysis 2 hours, 3 and 6 days after irradiation of typical macrophages, mononuclear cells (monocytes and lymphocytes), polimorphonuclear and mast cells from peritonium of test animals showed that radiation interfered in a differential way in the kinetics of peritoneal cells. (author)

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

    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.

  9. Radiolysis of D(+)-carnitine by 60Co-γ-radiation and formation of L(+)-β-methylcholine

    The radiolysis of D(+)-carnitine by 60Co-γ-radiation was examined to obtain optically active β-methylcholine. It was found that the radiolysis leads to a number of trimethylammonium bases but to no other betaines. (+)-β-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 (+)-β-methylcholine was formed from D(+)-carnitine is pharmacologically important, because acetyl-L(+)-β-methylcholine has a strong interaction with muscarinic receptors. (author)

  10. The regional genomic instability induced by 60Co γ-rays in B16 cells transfected by GFP

    Objective: To detect the regional genomic instability of B16 cells treated with 60Co γ-rays by a green fluorescence protein (GFP)-based genomic instability reporting system. Methods: Three groups were employed as non-transfection group, vector control group and transfection group. The GFP-marked reporter construct pCMV-EGFP2XhoI for regional genomic instability was successfully transfected into B16 cells using liposome. B16 cells were selected by screening of G418 with a series of concentrations and limiting dilution cultures to yield a single colony. B16 cells with the genomic instability report system were then irradiated by 60Co γ-rays at doses of 0, 2 and 4 Gy. The regional genomic instability of B16 cells was quantified by counting the number of cells with GFP expression. Results: B-16 cell strain steadily expressing the GFP-based genomic instability reporting system was established successfully. GFP-positive B16 cells were observed at 1 d after irradiation with 60Co γ-rays at doses of 2 and 4 Gy. Positive correlations between fluorescence intensity and dose and fluorescence intensity and time were also observed. The positive expression rate of GFP followed the increased of dose (F=36.55, 36.76, P<0.05) and time (t=-3.27, -3.16, -4.26, -6.11, -7.17, P<0.05), and differences between groups were significant. The positive expression rate of GFP increased significantly at 3 d, and maximum expression was observed at 5 d (2.46 ± 0.24 and 3.82 ± 0.35). The level was tending towards stability. Spontaneous GFP expression at a ratio of 1/600000 was observed in 0 Gy group after 2 weeks of culture. Conclusions: The regional genomic instability of B16 cells induced by 60Co γ-rays can be detected using a GFP-labelled genomic instability reporter system. (authors)

  11. Biological dosimetry in radiological protection: dose response curves elaboration for 60Co and 137Cs

    Ionizing radiation sources for pacific uses are being extensively utilized by modern society and the applications of these sources have raised the probability of the occurrence of accidents. The accidental exposition to radiation creates a necessity of the development of methods to evaluate dose quantity. This data could be obtained by the measurement of damage caused by radiation in the exposed person. The radiation dose can be estimated in exposed persons through physical methods (physical dosimetry) but the biological methods can't be dispensed, and among them, the cytogenetic one that makes use of chromosome aberrations (dicentric and centric ring) formed in peripheral blood lymphocytes (PBL) exposed to ionizing radiation. This method correlates the frequency of radioinduced aberrations with the estimated absorbed dose, as in vitro as in vivo, which is called cytogenetic dosimetry. By the introduction of improved new techniques in culture, in the interpretation of aberrations in the different analysers of slides and by the adoption of different statistical programs to analyse the data, significant differences are observed among laboratories in dose-response curves (calibration curves). The estimation of absorbed dose utilizing other laboratory calibration curves may introduce some uncertainties, so the International Atomic Energy Agency (IAEA) advises that each laboratory elaborates your own dose-response curve for cytogenetic dosimetry. The results were obtained from peripheral blood lymphocytes of the healthy and no-smoking donors exposed to 60Co and 137Cs radiation, with dose rate of 5 cGy.min.-1. Six points of dose were determined 20,50,100,200,300,400 cGy and the control not irradiated. The analysed aberrations were of chromosomic type, dicentric and centric ring. The dose response curve for dicentrics were obtained by frequencies weighted in liner-quadratic mathematic model and the equation resulted were for 60Co: Y = (3 46 +- 2.14)10-4 cGy-1 + (3.45 +- 0

  12. Aspects of the immune response against proteic antigens submitted to the effects of 60Co gamma radiation

    Considering the effects of gamma radiation on proteins and the capacity of the immune system to recognize modified macromolecules, we decided to evaluate some immunological aspects of B10.PL mice exposed to native or irradiated ovalbumin and bothrops toxin-1 (BthTx-1). In order to evaluate possible structural modifications of the molecules after being irradiated (60Co gamma rays), bothrops toxin-1 was analysed by electrophoresis, while ovalbumin was submitted to analytical size exclusion chromatography. The toxin was also analysed by ESI-mass spectrometry. Our results indicate that radiation promoted modifications on both the molecules. Aiming to compare the toxicity of the native and irradiated forms of the toxin, an in vitro cytotoxicity assay, using CHO cells, was performed. According to our results, the modified toxin was 5 folds less toxic than its native counterpart. Sera of animals immunized with the native and irradiated proteins were analyzed in order to evaluate levels of IgG, as well as to quantify specific isotopes. While the native proteins induced a predominant Th2 response, the irradiated molecules apparently promoted a switch towards a Th1 pattern. We also performed a cell proliferation assay with splenocytes from mice immunized with either the native or the irradiated proteins, cultured in the presence of the antigens. Our results indicate that both the forms of the proteins induced a similar proliferative response. These data indicate a potential use of detoxified proteins as antigens for immunization. (author)

  13. In Vivo Internal Decontamination of 134Cs and 60Co from Male Albino Rats

    The Present work aimed to evaluate the therapeutic role of prussian blue (PB), vermiculite and calcium trisodium salt of diethylenetriaminepentaacetic acid (DTPA) as internal de contaminants of radio-active cesium and/ or cobalt in adult male albino rats. Radionuclides were given as a single doses; 60Co was introduced orally, subcutaneously or intraperitoneally (ip) while 134Cs was taken orally or in combination with ip injection of 60Co. The de contaminants were supplied daily for three weeks immediately after 60Co or 134Cs intake; oral dose of PB + vermiculite treated the oral 134Cs group, oral and subcutaneous 60Co groups and combined 60Co and 134Cs groups. Rats receiving ip dose of 60Co were treated with daily ip dose of DTPA while the three de contaminants were added to the combined 60Co and 134Cs groups.Haemoglobin concentration (Hb), haematocrite percentage (Ht), red blood cells count (RBC's), as well as liver function tests (total bilirubine, total protein, albumin, globulin, A/ G ratio, alanine transaminase (ALT), spartic transaminase (AST) and alkaline phosphatase (ALP)) were analyzed in all groups. The data obtained revealed that internal contamination by radioactive materials causes a significant decrease in the RBC's counts, Hb concentration, haematocrit value, serum total proteins and albumin. On the other hand, the therapeutic agents caused a significant amelioration in the changes produced by internal contamination with variable degree. Thus, it could be concluded that the therapeutic agents might provide a protection against internal contamination hazards

  14. Development of technology for the large-scale preparation of 60Co polymer film source

    60Co sources (∼37 kBq) in the form of a thin film are widely used in position identification of perforation in offshore oil-well explorations. This paper describes the large-scale preparation of such sources using a radioactive polymer containing 60Co. 60Co was extracted into chloroform containing 8-hydroxyquinoline. The chloroform layer was mixed with polymethyl methacrylate (PMMA) polymer. A large film was prepared using the polymer solution containing the complex. The polymer film was then cut into circular sources, mounted on a source holder and supplied to various users

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

    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.

  16. Gamma radiation effects of {sup 60} Co on Bombyx mori (Lep., Bombycidae) modifying the silk fiber production; Influencia da radiacao gama ({sup 60} Co) na producao de fios de seda em Bombyx mori(Lep.,Bombycidae)

    Carneiro Junior, Francisco [Universidade Metodista de Piracicaba (UNIMEP), SP (Brazil); Bendassolli, Jose A. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)

    1997-12-01

    The present work aimed to verify the biological effects of the application of different doses of gamma radiation during the fifth instar of the silkworm catepillar. Sevently eight silkworm caterpillars (Bombyx mori) were irradiated with {gamma}{sup 60} Co radiation at the initial period of the fifth instar. The caterpillars were divided and classified in six batches of thirteen individuals each. Treatments 1 through 5 received 20, 40, 60, 80 and 100 Gy, respectively, and the control, also consisted of thirteen caterpillars, was not irradiated. The results showed a general increase in the silk fiber content in the irradiated batches compared to the control. The weight of the silk cocoons was higher with increasing doses of irradiation, from 20 to 80 Gy, respectively, followed by a decrease in weight in the treatment irradiated with 100 Gy. the results obtained in this experiment enable the conclusion that the radiation applied to the caterpillars significantly influenced the production of silk fiber in this species. (author). 4 refs., 2 figs., 3 tabs.

  17. Monte Carlo calculation of 60Co γ-ray's albedo-dose rate from the air

    The Monte Carlo calculation of 60Co γ-ray's albedo-dose rate from the air is reported. A formula is presented with which the relations of the albedo-doserate with some parameters are simulated and fitted

  18. Bioremediation of 60Co from simulated spent decontamination solutions of nuclear power reactors by bacteria

    The spent decontamination solutions generated from nuclear power reactors contain radionuclides of cobalt (60Co, 56Co and 57Co) along with a large excess (105) of non-radioactive metal ions (Fe, Ni and Cr). Our previous studies demonstrated that bioremediation of 60Co from simulated effluents using fungal biomass can provide an alternative to conventional ion exchangers. In this study, we used several bacteria to further improve the process of bioremediation by decreasing biomass requirement and treatment period. Further, metabolite activation in specific bacterial species resulted in enhanced bioremediation of 60Co from simulated effluent. Optimization of conditions in simulated effluent for the eight bacterial species to accomplish maximum 60Co removal is discussed. (author)

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

    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. PMID:26408852

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

    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...

  1. Multistep process of neoplastic transformation of normal human fibroblasts by 60Co gamma rays and Harvey sarcoma viruses

    Namba, M.; Nishitani, K.; Fukushima, F.; Kimoto, T.; Nose, K.

    1986-03-15

    As reported previously (Namba et al., 1985), normal human fibroblasts were transformed by 60Co gamma-ray irradiation into immortal cells with abnormal karyotypes. These transformed cells (KMST-6), however, showed a low cloning efficiency in soft agar and no transplantability. However, upon treatment with Harvey murine sarcoma virus (Ha-MSV), the cells acquired elevated clonability in soft agar and transplantability in nude mice. Ha-MSV alone, however, did not convert normal human fibroblasts into either immortal or tumorigenic cells. The Ha-MSV-transformed KMST-6 cells showed an enhanced expression of the ras oncogene, but normal and 60Co gamma-ray-transformed cells did not. Our current data suggest that gamma rays worked against normal human cells as an initiator, giving rise to chromosome aberrations and immortality, and that Ha-MSV, probably through its ras oncogene, played a role in the progression of the malignant cell population to a more malignant one showing enhanced colony formation in soft agar and tumorigenicity in nude mice.

  2. Study into the effect of 60Co γ-rays on the lymphocyte subests with monoclonal antibodies

    Three kinds of monoclonal antibodies, OKT4McAb, OKT8McAb and HI43McAb, were used in experiment to identify T helper (Th), T suppresser (Ts) and B lymphocytes respectively. After lymphocytes were exposed to 0.1 Gy, 0.25 Gy, 1 Gy and 4 Gy 60Co γ-rays, immediately, the author observed the radiation effect by means of the indirect immunofluorescence test. 200 cells were conted to obtain the percent of immunofluorescence positive cells. The results indicated that when the Th, Ts and B lymphocytes were irradiated by 0.1 Gy 60Co γ-rays, their abilities to combine with McAb decreased significantly. The radiation effect became more and more obvious with increasing radiation dosage. The percents of three kinds of the immunofluorescence positive cells were analysed with weighted linear regression methods. The correlation coefficients (r) of Th, Ts and B lymphocytes were 0.8131, 0.8832 and 0.9086 respectively. The significant tests of regression coefficient showed that the radiosensitivities of Ts and B lymphocytes had no significant difference and were higher than that of Th lymphocytes

  3. Study on the therapeutic effect of cytokine on acute radiation syndrome induced by 60Co γ ray exposure

    Objective: To examine the therapeutic effect of combined administration of rhIL-11 and rhG-CSF on acute radiation syndrome induced by 60Coγ ray exposure in beagles. Methods: Sixteen beagles were randomly divided into the control (n=5), symptomatic treatment group (n=5) and cytokine treatment group (n=6). All the beagles in the three groups were exposed to the whole-body irradiation of 60Co γ ray at a dose of 4.5 Gy. The animals in the second group accepted active symptomatic treatment. The animals in the cytokine treatment group were sub-cutaneously administered rhIL -11 and rhG -CSF besides active symptomatic treatment. Hemogram of peripheral blood, pristine apoptosis and necrosis ratio of nucleated cells, the content of IL-2 and IFN-γ in plasma and formation of bone marrow were used to evaluate the therapeutic effect. Results: In the cytokine treatment group, the animal' survival rate 45 days after exposure was increased and hemogram of peripheral blood was improved significantly. The rate of pristine apoptosis and necrosis of nucleated cell declined obviously. Early, the content of both IL-2 and IFN-γ in plasma was up significantly, then the content of IL-2 rapidly descended, but that of IFN-γ was relatively stable. Conclusion: The combined administration of rhIL-11 and rhG-CSF significantly improved the recovery of hematopoietic and immunological function. (authors)

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

    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 60CO radiotherapy. The dosage of Carboplatin was between 20 mg and 35 mg per square meter of body surface. The dosage of external 60CO 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)

  5. Study of the effect of 60Co γ-rays on lymphocyte subsets with monoclonal antibodies (McAb) and pokeweed mitogen (PWM)

    The efect of 60Co γ-rays on the lymphocytes were investigated with T4, T8, and HI4, McAbs. T and B lymphocytes were separated by rosetting procefures. After lymphocytes were labelled by T4 McAb, T4+ and non-T4+ cells were obtained by cell affinity chromatography method. When parts of T, B, T4+ and non-T4+ cells were exposed to 10 Gy 60Co γ-rays, the stimulating function of pokeweed mitogen and the effect of 60Co γ-rays on lympocytes were observed by technique of 3H-TdR incorporation. The results showed that when T4+, T8+ and HI43+ cells were labelled after irradiation at a dose of 0.1 Gy within one hour, the number of positive cells decreased significantly. The cells radiosensitivity in the group of T8+, and HI43+ lympocytes. PWM can stimulate both T and B cells but B cells were more sensitive to PWM. The response of B cells to PWM was the same as that of non-T4+ cells. The response of B lympocytes but such a kind of synergistic effect in T cell were irradiated by 10 Gy 60Co γ-rays, their synergistic effect disappeared. Neither synergistic nor suppressive effect was found between the cells in B group and non-T4+ group. When T4+, B and non-T4+ cells had been exposed to 10 Gy irradiation, the decreasing value of 3H-TdR incorporation in B and non-T4+ cells had no significant difference but their decreasing value was more obvious than that in T4+ group

  6. The studies of effects of 60Co γ-rays on DNA damage and repair in tumor cells

    The effects of 60Co γ-rays and its combination with hyperthermia on DNA strand breaks and their repair in L5178y cells were studied using alkaline elution technique. When the cells were heated at 43 degree C for 30 min, there was obvious inhibition of repair of DNA damage caused by γ-irradiation. The hyperthermia before irradiation produced better inhibiting effect than that after irradiation. The effects of radiation on DNA strand breaks and its repair in HL-60 cells and HL-60 (VCR) cells were analyzed using technique of hydroxyapatite chromatography and the results sowed that the extent of DNA strand breaks in HL-60 cells and HL-60 (VCR) cells induced by irradiation was not markedly different, but the power of repair of strand breaks and the radioresistance of function of DNA synthesis in HL-60 (VCR) cells were higher than those in HL-60 cells. The difference was obvious. The results suggest that the heterogeneity of radiosensitivity of leukemia cells is correlated with its drug resistance. (10 refs., 3 tabs.)

  7. Mechanisms of60Co uptake and loss by Scenedesmus obliquus and transfer to two benthic organisms

    The affinity of Scenedesmus obliquus for 60Co has been confirmed under various experimental conditions allowing for the age of cultures, the physiological state of the cells, the radioactivity level and stable cobalt concentration in the medium, and the acute or periodic nature of the contamination. The dry weight 60Co concentration factor may reach 4x104 in LCO culture medium and is about 104 in natural water. 60Co uptake by algae is a 95% passive phenomenon, initiated by radionuclide absorption on the cell walls and followed by intracellular diffusion in accordance with Fick's law. From the initial cationic form, radiocobalt develops anion forms at a rate proportional to the algal biomass, resulting in lower contamination of old and dense cultures. After transfer in natural or artificial nonradioctive medium, 60Co is eliminated by Scenedesmus obliquus, mainly as Co2+ ions, according to a two-phase exponential process with two biological half-lives. The study of radioactive cobalt transfer from algae to gammarids and to midge larvae reveals the extend to which phytoplankton predominate over water and sediment in contaminating these two organisms. The total 60Co uptake depends significantly on whether the cells are incorporated in or deposited on the sediment. No biomagnification phenomenon of the radionuclide was found in any case, as the transfer factor was less than 1. Depuration of 60Co by organisms involved a two-phase exponential process regardless of whether uptake occured directly or from food. The presence of sediment appears to reduce the 60Co desorption rate, but from 85 to 95% of the initial quantity is eliminated. This percentage does not depend on the transfer pathway or the presence of organic matter, and indicates very slight assimilation of radiocobalt ingested with algal cells

  8. Comparative uptake from sea water and tissue distribution of 60Co in marine mollusks

    Five different species of marine mollusks, Mytilus galloprovincialis Lmk., Tapes decussatus L., Cerastoderma (Cardium) edule (L.), Donax vittatus (da Costa) and Patella vulgata L., were exposed to 60Co-labelled sea water under laboratory conditions. After a 1-mo exposure, tested species reached different whole-body 60Co concentration factors (CF) over radioactive sea water of 73 +/- 27, 22 +/- 10, 84 +/- 25, 6.3 +/- 1.4 and 31 +/- 10, respectively, which are not dependent upon the size of mollusks. Equations for the experimental uptake curves, obtained using a multi-exponential model, indicate that 60Co uptake by mollusks involves two or three compartments, according to the species. In all species, the larger compartments turn over with long biological half-lives, dependent upon species. At the beginning of the experiment, 60CoCl2 added to sea water was mainly in cationic forms. These forms were progressively converted into anionic plus neutral forms most likely due to complex formation with organic ligands. With time this physico-chemical evolution had a lowering effect on 60Co bioaccumulation by mollusks. Analysis of 60Co in tissues revealed that Donax shell and mantle do not accumulate the radionuclide in great quantities, generating the low whole-body concentration factor found. In contrast, shell and mantle from all other species displayed variable but high CFs. Shell by itself accounts for more than half of the 60Co whole-body burden. Among soft tissues, gills and viscera displayed the highest CF and muscle the lowest. From these experiments, one may conclude that significant differences among species do exist regarding Co bioaccumulation potential

  9. Comparative uptake from sea water and tissue distribution of 60Co in marine mollusks

    Carvalho, F.P.

    1987-07-01

    Five different species of marine mollusks, Mytilus galloprovincialis Lmk., Tapes decussatus L., Cerastoderma (Cardium) edule (L.), Donax vittatus (da Costa) and Patella vulgata L., were exposed to /sup 60/Co-labelled sea water under laboratory conditions. After a 1-mo exposure, tested species reached different whole-body /sup 60/Co concentration factors (CF) over radioactive sea water of 73 +/- 27, 22 +/- 10, 84 +/- 25, 6.3 +/- 1.4 and 31 +/- 10, respectively, which are not dependent upon the size of mollusks. Equations for the experimental uptake curves, obtained using a multi-exponential model, indicate that /sup 60/Co uptake by mollusks involves two or three compartments, according to the species. In all species, the larger compartments turn over with long biological half-lives, dependent upon species. At the beginning of the experiment, /sup 60/CoCl2 added to sea water was mainly in cationic forms. These forms were progressively converted into anionic plus neutral forms most likely due to complex formation with organic ligands. With time this physico-chemical evolution had a lowering effect on /sup 60/Co bioaccumulation by mollusks. Analysis of /sup 60/Co in tissues revealed that Donax shell and mantle do not accumulate the radionuclide in great quantities, generating the low whole-body concentration factor found. In contrast, shell and mantle from all other species displayed variable but high CFs. Shell by itself accounts for more than half of the /sup 60/Co whole-body burden. Among soft tissues, gills and viscera displayed the highest CF and muscle the lowest. From these experiments, one may conclude that significant differences among species do exist regarding Co bioaccumulation potential.

  10. 紫外和60Co-γ诱变对树干毕赤酵母发酵木糖产乙醇的影响%Effects of Mutagenesis by UV lrradiation and 60Co-γlrradiation on Fermentation of Xylose to Ethanol by Pichia stipitis

    刘阳; 熊冬梅; 熊兴耀; 苏小军; 蔡柳; 曾璐

    2015-01-01

    ln this study, effects of UV irradiation and 60Coirradiation on fermenta-tion of xylose to ethanol by Pichia stipitis were analyzed to investigate the optimal mutagenic conditions. According to the growth curve and fermentation curve of P. stipi-tis, the optimal incubation duration and fermentation duration of P. stipitis mutant strain were 18 and 48 h, respectively. The cel concentration of original yeast liquid was 107 cel s/ml. After mutagenesis by UV irradiation and 60Coirradiation, yeast liquid was incubated in 20 g/L xylose media for 48 h. According to the results, after UV irradiation for 45-75 s, transformation efficiency reached 0.3794 g/g, which was 74.39% of the theoretical value; after irradiation with 800-1 000 Gy 60Co-γ, transforma-tion efficiency reached 0.3165 g/g, which was 62.06% of the theoretical value. Therefore, both UV irradiation and 60Coirradiation could improve the efficiency of xylose fermentation to ethanol by P. stipitis under appropriate conditions.%以树干毕赤酵母为出发菌株,研究紫外短波照射和60Co-γ辐照2种诱变方法对该菌种利用木糖产乙醇性能的影响,探讨较佳诱变条件。通过绘制菌体生长曲线及发酵曲线,确定了诱变菌最适宜的培养时长为18 h,诱变菌最适宜的发酵时长为48 h。原菌液浓度为107个/ml时,根据诱变后菌液在木糖浓度20 g/L中培养48h的结果可知,紫外处理45~75 s乙醇产率可达0.3794 g/g,为理论值的74.39%,辐照处理800~1000 Gy,乙醇产率可达0.3165 g/g,为理论值的62.06%。因此,紫外及辐照这2种诱变方式在合适的参数条件下均能提高树干毕赤酵母利用木糖产乙醇的转化率。

  11. Radiation-induced micronucleus formation in mice bone marrow after exposure to different doses of 60Co gamma radiation

    The frequency of micronuclei formation in the polychromatic erythrocytes and normochromatic erythrocytes was studied at 12 and 24th post-irradiation in mice bone marrow whole-body exposed to 0, 0.5, 1.0, 2.0, 3.0 and 4.0 Gy of 60Co gamma radiation. It was observed that the frequency of MPCE (micronucleated polychromatic erythrocytes) and MNCE (micronucleated normochromatic erythrocytes) increased with increase in exposure dose in both intervals studied. The data analyzed using the linear quadratic (Y+C+αD+βD2) equation. It was found that the data for MPCE and MNCE fitted best for linear quadratic model. (The PCE/NCE ratio declined with increase in exposure dose in both intervals and this decline was dose related. (author). 28 refs., 1 tab

  12. Tl response of KMgF3 :Lu+PTFE depending on the dose of gamma radiation of 60Co

    Due to the great interest in Tl dosimetry for measuring the levels of radiation doses, as environmental as in the different medical radiation applications in different laboratories of the World it is continued in the searching of new Tl materials with optimum dosimetric characteristics and low cost. In this work the obtained results when irradiating Tl dosemeters of KMgF3 :Lu + PTFE with gamma radiation of 60 Co are presented. Such results showed that this material presents linearity of response depending on the dose between 0.016 to 100 Gy. Although it is continued with the characterization tests it is able to say that this Tl new material can be used for dosimetric aims. (Author)

  13. Activity evaluation of 60Co, 137Cs, 152Eu, 154Eu, 14C and total β in graphite from the thermal column of Romanian TRIGA research reactor

    Several methods were investigated for identification and activity evaluation of 60Co, 137Cs, 152Eu, 154Eu, 14C and total β in graphite samples collected from the thermal column of Romanian research reactor. An ORTEC DIGIDART multichannel gamma spectrometer was used for measurement of 60Co, 137Cs, 152Eu and 154Eu. The main contribution to the radioactivity of graphite comes from 60Co, 152Eu and 154Eu. Combustion of graphite samples using a PerkinElmer sample oxidizer was utilized for total oxidizing of 14C to gaseous carbon dioxide. A TRI-CARB Packard liquid scintillation analyzer was used for 14C counting. The degree of 14C recovery in the analyzed standard samples was higher than 98%, and the 14C retention degree in the circuits of combustion system was less than 0.08%. To evaluation of total β activity in the irradiated graphite, the samples were measured using a proportional counter. The mean total β activity in the irradiated graphite samples was about 3000 Bq/g. (authors)

  14. Effects of different premature chromosome condensation method on dose-curve of 60Co γ-ray

    Objective: To study the effect of traditional method and improved method of the premature chromosome condensation (PCC) on the dose-effect curve of 60Co γ ray, for choosing the rapid and accurate biological dose estimating method for the accident emergency. Methods: Collected 3 healthy male cubits venous blood (23 to 28 years old), and irradiated by 0, 1.0, 5.0, 10.0, 15.0, 20.0 Gy 60Co γ ray (absorbed dose rate: 0.635 Gy/min). Observed the relation of dose-effect curve in the 2 incubation time (50 hours and 60 hours) of the traditional method and improved method. Used the dose-effect curve to verify the exposure of 10.0 Gy (absorbed dose rate: 0.670 Gy/min). Results: (1) In the traditional method of 50-hour culture, the PCC cell count in 15.0 Gy and 20.0 Gy was of no statistical significance. But there were statistical significance in the traditional method of 60-hours culture and improved method (50-hour culture and 60-hour culture). Used the last 3 culture methods to make dose curve. (2) In the above 3 culture methods, the related coefficient between PCC ring and exposure dose was quite close (all of more than 0.996, P0.05), the morphology of regression straight lines almost overlap. (3) Used the above 3 dose-effect curves to estimate the irradiation results (10.0 Gy), the error was less than or equal to 8%, all of them were within the allowable range of the biological experiment (15%). Conclusion: The 3 dose-effect curves of the above 3 culture methods can apply to biological dose estimating of large doses of ionizing radiation damage. Especially the improved method of 50-hour culture,it is much faster to estimate and it should be regarded as the first choice in accident emergency. (authors)

  15. 60Co deposition on carbon-steel structural materials after seawater infiltration in BWR plant

    Seawater infiltration occurred during shutdown of the Hamaoka Unit 5 (H-5). Chloride ion (Cl-) is known to affect the corrosion behavior of carbon steel, and it may change the properties of the oxide film formed on the surface. 60Co deposition in high-temperature water is strongly related to the oxide film properties, and any change in the properties may affect the 60Co deposition after the plant is restarted. This paper shows the results of 60Co deposition tests of carbon steels under simulated H-5 water conditions. Specimens for the 60Co deposition tests were prepared in three steps, which simulated the conditions of normal plant operation, seawater infiltration, and chemical decontamination after the infiltration. The first step was a prefilming step under Normal Water Condition (NWC). The second step included two different conditions: seawater infiltration and keeping after infiltration. Prefilmed specimens were immersed in 450 ppm Cl- diluted artificial seawater at 513 K for 24 hours. Following that, the specimens were immersed in 50 ppm Cl- diluted artificial seawater at 323 K for 100-500 hours. During the second step, the prefilming oxide (NiFe2O4) flaked off in spots. In the third step, the oxide remaining on some specimens after the second step was removed chemically. The three types of prepared specimens, that is, a prefilmed specimen, an exposed specimen, and an oxide-removed specimen, were used for the 60Co deposition tests using 0.015 Bq/cm3 60Co solution for 500 or 1000 hours under NWC conditions. After the deposition tests, the 60Co activity was measured with a Ge detector. From the results of the deposition test, at the spots where flaking occurred in the second step, only loose hematite was formed, and generation of a new protective film was not observed. The amount of 60Co deposited on the exposed specimen was more than that on the prefilmed and oxide-removed specimens. The simulated infiltrating conditions inhibited the regeneration of a

  16. Dominant lethal effect of gamma radiation of 60Co in Biomphalaria glabrata (SAY, 1818)

    Germ cell mutations are used in ecotoxicological studies as biomarkers of population effects and indicators of ecological changes. Biomphalaria glabrata, a freshwater mollusk, is a good experimental model for biomonitoring studies due to its biological characteristics and the ecological importance of this invertebrate group. The dominant lethal test was established in B. glabrata for the detection of germ cell mutations. Results with chemical mutagens showed that this system is efficient, specific and sensitive in the evaluation of germ cell mutations induced by reference mutagens. In this work, the dominant lethal effects of gamma radiation of 60Co were studied. A preliminary experiment was done to establish the dose range and to estimate the chronology of spermatogenesis in B. glabrata. This estimate is possible because of the uniformity in response to ionizing radiation between germ cells at homologous stages of spermatogenesis in widely different species. In general, pre-meiotic germ cells are less sensitive to the induction of lethal dominant mutations than post-meiotic cells. This effect can be attributed to: young gametogenic cells - mitotically active - have greater repair ability from sub-lethal DNA damage and there is a selective elimination of the damaged cells. In our system: induction of lethal dominant mutations causes an increase in the frequency of malformations and, cytotoxic effect is displayed as a reduction in the crossing rates. Total duration of spermatogenesis was estimated in approximately 36 days, with the following distribution of stages: 1 to 13 days - spermatogonia, 14 to 20 days - spermatocytes, 21 to 36 days - spermatids and spermatozoa. Based on this chronology, irradiated wild-type snails with 2,5; 10 and 20Gy and crossed with non-irradiated albino snails after 7, 17, 23, 30 and 36 days. The frequencies of malformations in the heterozygous wild-type offspring of the nonirradiated albino snails were used as indicator of germ cell

  17. Monte Carlo dosimetry for 125I and 60Co in eye plaque therapy

    Monte Carlo calculations of radiation dosimetry using morse code are performed for 125I and 60Co point sources in a cylindrical head phantom that simulates the geometry of eye plaque therapy for choroidal melanoma. We obtain the dose variation in the eye at submillimeter intervals over distances as close as 1 mm and up to 2.5 cm from the source. The calculations for 125I are performed for the phantom media of water, protein, and a homogenized protein--water mixture simulating the composition of the eye. Relative dose functions for 125I for these phantom media are fitted to second-degree polynomials. Agreement is found with published results. The relative dose function for 60Co at eye position in the water head phantom is fitted to a third-degree polynomial and compared with that for 60Co at the center of a large water sphere. A boundary effect due to the head phantom--air interface on the dose distribution for 60Co is demonstrated. The dose falloff with distance is faster for the eye geometry compared with the bulk geometry. We also show that the relative dose distributions within the tumor are comparable for 125I and 60Co by comparing their relative dose functions. This result is consistent with the success of clinical trials of large melanoma treatments with 125I plaques

  18. Effect of 60Co gamma irradiation on metal--ceramic systems

    The following systems were studied: silver supported catalysts, silver powders, sandwich type samples (Ag/Ca(OH)2/Ag), calcium hydroxide, calcium carbonate, and a silver galvanic cell. The following experimental methods were used: ethylene oxidation experimental set-up, ESCA and AES, experimental set-up to study gas products from radiation decomposition, x-ray diffraction method, SEM, BET surface measurements, and measurements of current in a silver galvanic cell. It is suggested that observed Co-60 gamma ray effects on metal ceramic systems are electrochemical in nature and can be explained by radiation chemistry. A review of literature dealing with Co-60 gamma rays and solids is presented

  19. Preoperative irradiation in carcinoma of the pancreas. [/sup 60/Co or 46 MeV photons

    Pilepich, M.V. (Washington Univ., St. Louis, MO); Miller, H.H.

    1980-11-01

    Seventeen patients with carcinoma confined to the pancreas and the peripancreatic area received preoperative radiation therapy in an attempt to increase the resectability rate and to reduce the incidence of recurrence. The tumors were considered either unresectable or of borderline resectability. The radiation dose ranged between 4000 to 5000 rads, the majority of patients (75%) receiving 4400 to 4600 rads in 4 1/2 to 5 weeks. After a period averaging six weeks the patients were reevaluated for surgery. Eleven patients were explored and six underwent radical resection. Two patients remained disease free after five years. Pancreatic resection is feasible following a course of preoperative radiotherpy to a moderately high dose. It is suggested that the response of the primary tumor to radiotherapy be used as a criterion for selecting patients for reexploration and resection.

  20. The effect of 60Co γ-rays on the contents of paramylon and trehalose in Euglena gracilis

    Full text: It is reported that the non-reducing disaccharide trehalose is accumulated in various organisms and protects biomolecules against various environmental stresses including heat shock, osmotic shock, and oxidative stresses. Euglena (Euglena gracilis) is photosynthetic unicellular organisms which is classified both as animal and as plant because of its motility. In our previous study, it was shown that salt stress causes degradation of paramylon, the reserve carbohydrate of Euglena, and trehalose, the degraded product of paramylon, accumulated simultaneously to maintain the osmotic pressure of Euglena cells. Euglena is known to be radiation-resistant more than Escherichia coli and other bacteria. Therefore, we have investigated whether or not the same phenomenon could be observed in Euglena after 60Co-gamma irradiation. Exposure of the native Z strain and chloroplast-deficient SM-ZK strain of Euglena to a dose of 500 kGy induced significant paramylon degradation and trehalose accumulation during the incubation in the Koren-Hunter culture medium containing glucose as carbon source after the irradiation. Forty percent of the paramylon was degraded within 10-hr incubation after the irradiation but accumulated trehalose content was about one sixth of that by salt stress. Trehlose accumulation disappeared when the irradiated cells were incubated in phosphate buffer but it recovered when glucose is added to the buffer to the same concentration as K-H media. These results suggest that trehalose accumulation in irradiated Euglena cells plays a role in protecting cellular constituents from oxidative damage caused by gamma-irradiation independently of the response to salt stress

  1. Characterization of 60Co dose distribution using BEAMnrc Monte Carlo code

    In this study BEAMnrc based on EGSnrc as Monte Carlo code has been used for modeling and simulating 60Co machine in radioisotope centre of Khartoum (RICK), Two fields size ( 5 cm x 5 cm and 35 cm x 35 cm), were been studied, to define the characterization of 60Co machine and to investigate the effect of increasing the surface to skin distance (SSD) on the 60Co machine properties, e.g.; beam profile and percentage depth dose (Pdd). For the narrow field size there is a small change observed in the curves representing beam profile and the percentage depth dose when increasing the distance by 5 cm, for the wide fi ld size there relatively clear different in curves. The study results been compared with other previous studies and clear consistence observed. (Author)

  2. Soil to plant transfer of 137Cs and 60Co in Ferralsol, Nitisol and Acrisol

    In this study, soil to plant transfer factor values were determined for 137Cs and 60Co 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 137Cs, and organic matter for 60Co. Results of sequential chemical extraction were coherent with root uptake and allowed the recognition of the role of iron oxides on 137Cs behaviour and of Mn oxides on 60Co 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

  3. High dose rate sup 60 Co-RALS intraluminal radiation therapy for advanced biliary tract cancer with obstructive jaundice

    Tamada, Toshiaki; Yoshimura, Hitoshi; Yoshioka, Tetsuya; Iwata, Kazuro; Ohishi, Hajime; Uchida, Hideo (Nara Medical Univ., Kashihara (Japan))

    1991-12-01

    High-dose-rate intraluminal irradiation with a {sup 60}Co remote afterloading system, using our newly developed applicator, was performed in 15 cases of advanced biliary tract cancer (2 gallbladder cancers, 13 cholangiocarcinomas). The applicator which was thin with an outer diameter of 14 Fr had a double lumen which included a small lumen for a guide wire for easy exchange to a drainage tube. Therefore, the irradiation procedure could be easily finished in a short time within little distress to the patient. The tumor marker CA1 19-9 was useful in assessing the therapeutic effect and follow-up observation after treatment. The average tube-free period and survival time were 5.9 months and 8.3 months, respectively. Histopathological examination of the cases autopsied showed that the combination of intraluminal (30 Gy) and external (30 Gy) irradiation offered good local control of the cancer that was within 1 cm from the source. Cholangiocarcinoma with relatively short length of obstruction, stage III or stage IV when the cancer infiltration was localized around the bile duct, achieved a comparatively long survival time. It was suggested that the combined use of high-dose-rate intraluminal radiotherapy, with precisely delivered radical radiation to tumors localized in the bile duct wall, and external radiotherapy delivered as additional radiation to the surrounding bile duct would provide radiotherapeutic advantage and contribute to survival after treatment for advanced biliary tract cancer. (author).

  4. Quality control and calibration of the ZEUS forward and rear calorimeters with 60Co sources

    We present the motivation for and the design of a mobile 60Co source system used as part of the quality control and calibration monitoring scheme for the ZEUS calorimeters. A 2 mCi 60Co source is pushed by a computer controlled drive mechanism through guide tubes which extend into the calorimeter. Measurements of induced photocurrents as a function of the source position allow checks on the calorimeter response. We present results obtained during the initial scan of all 1024 towers of the forward and rear calorimeter modules. (orig.)

  5. In vivo effect of some home spices extracts on the Toxoplasma gondii Tachyzoites

    Najia A Al-Zanbagi

    2009-01-01

    Full Text Available Toxoplasmosis drugs have the longest history and are still the first choice for most conditions. Alternative drugs such as Co-trimoxazole and Tetracycline have been tried and acclaimed successful. The lack of general acceptance, however, is an indication that the results are not very convincing. A wide range of antibiotics is urgently needed for patients with drug reaction or resistance problems. The anti-toxoplasmic activity of water and ethanol extracts as well as the oil of some home spices (Piper nigrum, Capsicum frutescens, Cinnamomum cassia and Curcuma longa, were evaluated in murine models of intraperitoneal infection using the RH strain of Toxoplasma gondii. Female mice were infected with 2x10 [2] tachyzoites/ml, and then treated intraperitoneally with the home spices at 100 and 200 mg/kg/day for seven days. The tested extracts reduced the mean number of tachyzoites present in the peritoneal fluid of the experimental mice. The most effective extract was Curcuma longa ethanol extract which showed a 98.6% and 99.2% inhibition of the growth of Toxoplasma tachyzoites in 100 and 200 doses respectively compared to the control infected untreated mice.

  6. 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

    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.

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

    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)

  8. Use of 60Co gamma radiation in increased levels of total polyphenol extracts of bark of Schinus terebinthifolius Raddi

    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 60Co. 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 60Co 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)

  9. The measurement of some signals for control system of 60Co scan system for freight train

    The 60Co Scan system for Freight Train has an automatic inspection flow, so it is very crucial that the measurement of the signals for the automatic control system. In this paper, we mainly introduce the identification of the intervals between two freight train carriage, the measurement of the train speed, and identification of freight train

  10. Design and realization of the review station of 60Co train inspection system

    The author illustrates design and realization of the review station software of 60Co train inspection system (TCT-SCAN). The software have two remarkable functions: processing images of carriages and accessing information of inspection, which are provided by two processes respectively. The communication between processes is realized by memory-mapped file

  11. 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

    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

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

    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

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

    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

  14. Study of gamma radiation from 60Co effects on Apis mellifera venom: biochemical, pharmacological and immunological aspects

    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 60Co 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 PLA2 activity analysis, lethality assay (LD50). Biodistribution studies was carried out after labelling native and irradiated bee venom with 99mTc. 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 PLA2 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. Biodistribution studies showed

  15. Effects of 60Co γ-rays radiation on biological characters of Platanus acerifolia Willd. weed and seedlings

    The dry seeds of Platanus acerifolia Willd. were irradiated by different doses of 60Co γ-rays, and the effect of the radiation on M1 were investigated. Results showed that the seed germination rate, emerged seedling rate and survival seedling rate of Platanus aceriflia Willd. Decreased with dose increase at the dose of 50-400 Gy, as well as the plant height, fresh weight and length of root. The radiation inhibited the seeding growth significantly. Compared with CK, the true leaf emerging time of samples irradiated at 50-250 Gy was late for 2, 5, 9 and 14d, respectively. But the young seedlings of samples treated at 300-400 Gy were severely twisted and abnormal, and gradually died after 15d. Based on the data of seeding rate and root growth, it is concluded that the semi-lethal radiation dose of Platanus acerifolia Willd. dry seed was 50 Gy, and the suitable dose range for radiation breeding was 50 to 250 Gy. (authors)

  16. Clinical data from one year follow-up of victims of the radiation accident with 60Co in Bulgaria.

    Djounova, J; Guleva, I; Negoicheva, K; Mileva, I; Panova, D; Rupova, I

    2014-09-01

    A severe radiation accident occurred on 14 June 2011 in an industrial irradiation facility for medical equipment sterilization in Bulgaria. Five people were exposed for 5-10 min to a 60Co source containing 137 TBq. The Emergency Department of the National Centre of Radiobiology and Radiation Protection (NCRRP), Bulgaria, put into practice the plans for providing medical care in radiation accidents and the procedures developed for assessment of injury severity, the decision-making algorithm regarding subsequent treatment, and the therapy for persons affected. The activities performed for initial assessment of the severity of injury of irradiated patients were published in 2012. Based on predictive assessments of the severity of radiation damage, it was decided that the victims required hospitalization at a specialized hematology clinic. Percy Hospital in Paris was chosen for this purpose. The aim of this report is to present the results of 1-y follow-up for three of the victims. Sadly, 1 mo after the accident, Patient 4 died from a heart attack. The medical opinion was that this was not a direct outcome of the irradiation. Patient 5 was only followed up for 4 mo (118 d) because medical follow-up is voluntary, and despite repeated calls, the patient did not respond. Medical examinations by a physician as well as hematology and biochemical tests were performed using standard laboratory methods. The obtained results were compared to the victims' personal reference limits obtained from annual health monitoring. After the accident, the recovery to normal content of peripheral blood cells was observed in all victims. Nevertheless, there were observed cases of thrombocytopenia, granulocytopenia, and leucocytopenia at various times after exposure. During the period of observation, morphological changes in red blood cells such as anisomicrocitosis, macrocytes, megalocytes, and polychromatic erythrocytes were demonstrated. During the 1-y observation period, all victims showed

  17. Effect of the ionizing radiation of the 60Co on the radiological properties of guar gum and carboxymethylcellulose for the food industry use

    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 60 Co ionizing radiation. (author)

  18. Breeding of 'fu 296' rice with high yield and good quality by 60Co γ-rays irradiaton dry seeds of hybrid F1

    F1 dry seeds of Z96-03 x Guangchangzhan were irradiated by 80 Gy 60Co γ-rays. The early maturity inbred indica rice 'Fu 296' was developed through the pedigree breeding method. It has the primary characteristics of high and stabilizing grain yield, better grain quality, ideotype canopy architecture, erect leaves, taller plant height, stiff and sturdy stems, resistance to lodging, large panicle and higher filled seed rate, et al. Fu 296 had passed the cultivar registration of Hunan Province in March, 2008. (authors)

  19. Effect of 60Co gamma radiation on insects infesting rice during storage. Part III. Oryzaephylus surinamensis L., Cryptolestes pusillus S. and Cryptolestes ferrugineus S. (Cucujidae; Coleoptera)

    Losses in rice grain in quantity and quality during storage are caused by insects infestations. In this paper the effect of 60Co gamma radiation on the mortality of Oryzaephilus surinamensis L., Cryptolestes pusillus S. and Cryptolestes ferrugineus S. adults was study. Insects were irradiated with doses from 0,20 to 1,00 kGy at dose rates from 0,97 to 0,94 kGy.h-1. After the treatment, the radiation damages were evaluated taking in consideration the sterility and mortality produced in the irradiated populations. According to the experimental results it was confirmed that irradiation doses from 0,40 to 0,60 kGy were effective to control the insects pests of stored rice in Cuba

  20. Comparison of dosimetric standards of Canada and France for photons at 60Co and higher energies

    We report the results of a comparison of the dosimetric standards of Canada and France for photon beams at 60Co and a few higher energies. The present primary standard of absorbed dose to water for NRC, Canada is based on measurements made with a sealed water calorimeter. The corresponding standard of the LNHB, France is based on measurements made with a graphite calorimeter at 60Co energy and transferred to absorbed dose to water for 60Co and higher-energy photon beams using both ion chambers and Fricke dosemeters as transfer instruments. To make this comparison, we used three graphite-walled NE2571 Farmer chambers. The absorbed dose to water determined by the LNHB was greater than that determined by NRC by 0.20% at 60Co energy. This difference is not significant given the uncertainties on the standards. In order to do the comparison for higher-energy photons, we interpolated the NRC data set at the beam qualities used at the LNHB. When %dd(10)x is used as the method of specifying beam quality, the determination of absorbed dose to water by the LNHB is about 0.2% greater than that determined by NRC and consistent with the results at 60Co. However, when using TPR20,10 as the beam quality specifier, the LNHB determination is greater than the NRC's determination by 0.8% and 1.2% at 12 and 20 MV respectively. This discrepancy, which systematically increases with increasing energy, eventually exceeds the uncertainties in the ratio of the standards, estimated to be 0.7%. This underscores the importance of selecting the method of specifying beam quality, either %dd(10)x or TPR20,10, at least for the 'soft' beams used by NRC in this comparison. In the case of the air kerma standards, which were also compared at 60Co energy, the LNHB determination was greater than NRC's by 0.14%, which is not significant given the uncertainties on the standards. (author)

  1. A new type of quinoxalinone derivatives affects viability, invasion, and intracellular growth of Toxoplasma gondii tachyzoites in vitro.

    Rivera Fernández, Norma; Mondragón Castelán, Mónica; González Pozos, Sirenia; Ramírez Flores, Carlos J; Mondragón González, Ricardo; Gómez de León, Carmen T; Castro Elizalde, Kitzia N; Marrero Ponce, Yovani; Arán, Vicente J; Martins Alho, Miriam A; Mondragón Flores, Ricardo

    2016-05-01

    Quinoxalinone derivatives, identified as VAM2 compounds (7-nitroquinoxalin-2-ones), were evaluated against Toxoplasma gondii tachyzoites of the RH strain. The VAM2 compounds were previously synthesized based on the design obtained from an in silico prediction with the software TOMOCOMD-CARDD. From the ten VAM2 drugs tested, several showed a deleterious effect on tachyzoites. However, VAM2-2 showed the highest toxoplasmicidal activity generating a remarkable decrease in tachyzoite viability (in about 91 %) and a minimal alteration in the host cell. An evident inhibition of host cell invasion by tachyzoites previously treated with VAM2-2 was observed in a dose-dependent manner. In addition, remarkable alterations were observed in the pellicle parasite, such as swelling, roughness, and blebbing. Toxoplasma motility was inhibited, and subpellicular cytoskeleton integrity was altered, inducing a release of its components to the soluble fraction. VAM2-2 showed a clear and specific deleterious effect on tachyzoites viability, structural integrity, and invasive capabilities with limited effects in host cells morphology and viability. VAM2-2 minimum inhibitory concentration (MIC50) was determined as 3.3 μM ± 1.8. Effects of quinoxalinone derivatives on T. gondii provide the basis for a future therapeutical alternative in the treatment of toxoplasmosis. PMID:26888289

  2. Coordinated progression through two subtranscriptomes underlies the tachyzoite cycle of Toxoplasma gondii.

    Michael S Behnke

    Full Text Available BACKGROUND: Apicomplexan parasites replicate by varied and unusual processes where the typically eukaryotic expansion of cellular components and chromosome cycle are coordinated with the biosynthesis of parasite-specific structures essential for transmission. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe the global cell cycle transcriptome of the tachyzoite stage of Toxoplasma gondii. In dividing tachyzoites, more than a third of the mRNAs exhibit significant cyclical profiles whose timing correlates with biosynthetic events that unfold during daughter parasite formation. These 2,833 mRNAs have a bimodal organization with peak expression occurring in one of two transcriptional waves that are bounded by the transition into S phase and cell cycle exit following cytokinesis. The G1-subtranscriptome is enriched for genes required for basal biosynthetic and metabolic functions, similar to most eukaryotes, while the S/M-subtranscriptome is characterized by the uniquely apicomplexan requirements of parasite maturation, development of specialized organelles, and egress of infectious daughter cells. Two dozen AP2 transcription factors form a series through the tachyzoite cycle with successive sharp peaks of protein expression in the same timeframes as their mRNA patterns, indicating that the mechanisms responsible for the timing of protein delivery might be mediated by AP2 domains with different promoter recognition specificities. CONCLUSION/SIGNIFICANCE: Underlying each of the major events in apicomplexan cell cycles, and many more subordinate actions, are dynamic changes in parasite gene expression. The mechanisms responsible for cyclical gene expression timing are likely crucial to the efficiency of parasite replication and may provide new avenues for interfering with parasite growth.

  3. Cataract production in mice by fractionated doses of 12C particles or 60Co gamma radiation

    The objective of our study was to evaluate the sparing effects of long-term dose fractionation with high LET 12C ions and 60Co gamma radiation. Because cataract examinations could be performed nondestructively, mice dedicated to studies of life shortening and carcinogenic response to photons and heavy charged particles were available for study. The project's staffing was such that slit-lamp biomicroscopic examinations could be performed only on CB6F1 male mice that received single or fractionated doses of 225 MeV/amu 12C ions and animals that received a single or fractionated dose of 60Co gamma radiation of 4.17 Gy. A total of 24 fractionated doses were administered weekly. Using a semiquantitative scoring system, the severity of cataract response was evaluated at three sample times following the single dose or first fractionated dose

  4. Removal of 60Co and 134Cs from radioactive process waste water by flotation

    The removal of 134Cs and 60Co from radioactive process waste water using cetyl pyridinium chloride (CPC) as a collector and cobalt(II) hexacyanoferrate(II) as a precipitant for 60Co and sorbent (ion exchanger) for 13'4Cs was intensively investigated and the best removal conditions could be established. The results indicate that under the optimum conditions removals higher than 96% and 97% could be achieved for Co(II) and Cs(I), respectively. Cobalt(II) hexacyanoferrate(II) was found to have high affinity for cesium and can preferentially remove it in presence of relatively high amounts of other alkali or alkaline earth cations. A two-stage flotation process was successfully tested for the removal of both Cs(I) and Co(II) from waters containing both cations. (author) 59 refs.; 8 figs.; 2 tabs

  5. National comparison of activity measurements of 131I, 60Co, and 133Ba in Indonesia

    National comparisons of radioactivity measurements of 131I and 60Co (in 2010) and of 133Ba (in 2011) were carried out within the framework of the National Radiation Metrology Laboratory Program of Indonesia, coordinated by PTKMR-BATAN. Eleven laboratories took part in the comparison, and all measurements were made using gamma spectrometry, on point sources with an activity between 2000 Bq and 6000 Bq. Several laboratories reported values which were more than 10% different from the reference value for 131I and 133Ba. Possible reasons for these differences are discussed. This program will be continued with other radionuclides to maintain and control quality assurance for the local laboratories. - Highlights: • PTKMR-BATAN coordinated national comparison of 131I, 60Co and 133Ba. • Eleven laboratories took part in the comparison. • All measurements were done using gamma spectrometry methods. • For 131I and 133Ba, 3 laboratories have more than 10% difference from reference laboratory value

  6. The teratogenic effects of low dose 60Co γ-rays on the early pregnant rats

    The pregnant Wistar rats were exposed to 0.5 Gy and 1.0 Gy 60Co γ-rays at the 9th day after conception. The results: 60Co γ-rays at dose of 1.0 Gy could induced many defects: excenphaly, hydrocephalus, gastroschisis, cleft palate and cleft lip, anophthalmia, microphthalmia, shorten tail and absent tail in surviving fetuses. The growth retardation was found from the parameters of fetal weight, height, head circle and development of skeleton. In the group of radiation dose 0.5 Gy, only hydrocephalus, absent tail and growth retardation of skeleton appeared. The results suggest that low-dose exposure in the early pregnant rats can induce fetal defects and growth retardation. The probable mechanism of teratogen and growth retardation was discussed. The cAMP levels of brain and liver of rat fetuses were reported

  7. Long-term clearance of accidentally inhaled 60Co aerosols in humans

    Long-term body retention was measured on six workers inhaling 60Co aerosols incidentally during manipulation with a high activity 60Co source. An improved whole body counter technique and calibration provided good conditions to follow the body clearance over 4 years. A two-detector profile scanning arrangement was used to measure the activity distribution 'in vivo' over the lung region. The observed whole body retention followed a two-exponential time function between 10-1500 days. The consistency of the measured retention pattern with ICRP inhalation model was investigated assuming different aerosol size distributions. A possible extension of ICRP lung model is proposed to take into account the actual pulmonary lung clearance determined individually. (R.P.) 29 refs.; 15 figs.; 6 tabs

  8. The realization of 60Co container inspection system's check-in station

    The functional design and realizing mode of the check-in station software of 60Co container inspection system are illustrated. Check-in station plays an important role in 60Co container inspection system. It undertakes the tasks of inputting the container's relative information, flow control of containers waiting for inspections and the information transfer. Of all the information of check-in station inputs, the customs declaration or the encasement declaration is the main information to be input. In this software, they are input by scanner and the control module of scanner is programmed according to Twain criterion. As Twain criterion is generally followed by image industry, this software has high generality and facility independence

  9. Recognition of tachyzoite and bradyzoite antigens of Toxoplasma gondii by infected hosts.

    Makioka, A; Suzuki, Y.; Kobayashi, A

    1991-01-01

    Western immunoblots of tachyzoite and bradyzoite antigens of Toxoplasma gondii were probed with antisera from rabbits and mice at intervals between 2 and 8 weeks after infection and with human antisera with various titers of antibody. With rabbit and mouse antisera, two groups of antigens with molecular masses of 54 to 63 kDa (designated 58.5-kDa antigens) and 26 to 29 kDa (designated 27.5-kDa antigens) were demonstrated commonly for both stages, while those antisera reacted strongly with tac...

  10. Monte Carlo simulation of a digital coincidence system applied to 60Co standardization

    The Laboratorio de Metrologia Nuclear (LMN) at the Instituto de Pesquisas Energeticas e Nucleares (IPEN) is developing a Digital Coincidence System (DCS), including the design of the proper acquisition electronics and analysis software. A brief discussion about the measurement methodology and the electronics operation is presented. This work is focused on the results of the designed software (the Monte Carlo simulation of 60Co decay data and the Coincidence Data Analysis), which are in good agreement with the experimental data. (author)

  11. Studies on bioaccumulation of 152Eu, 137Cs, 60Co by different algal genera

    In the present paper, the bioaccumulation of a mixture of potentially hazardous, long lived radionuclides 152Eu, 137Cs and 60Co by five algal genera of three different family, viz.: Lyngbya and Phormidium from cyanophyceae; Phizoclonium and Chaetomorpha from chlorophyceae and Catenella from rhodophyceae have been studied. Because of the long half life and high solubility, these radionuclides are considered the most hazardous in the nuclear spent fuel

  12. Image acquisition, transmission and assignment in 60Co container inspection system

    The author describes the data acquisition mode and image reconstruction method in 60Co container inspection system, analyzes the relationship between line pick period and geometry distortion, makes clear the demand to data transmitting rate. It discusses several data communication methods, draws up a plan for network, realizes automatic direction and reasonable assignment of data in the system, cooperation of multi-computer and parallel processing, thus greatly improves the systems inspection efficiency

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

    Milenković Aleksandra S.; Smičiklas Ivana D.; Marković Jelena P.; Vukelić Nikola S.

    2014-01-01

    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 r...

  14. A case study of medical intervention following intake of 60Co

    The present study is based on the follow up study of a case of 60Co internal contamination using whole body counting and bioassay analysis. The effect of medical intervention applied on the subject is studied. Medical intervention with D-penicillamine (250 mg x 4 daily) orally was administered from thirteenth day of initial exposure for about a fortnight, which showed reduction of activity present by 33.4% through urine. (author)

  15. Development and characterization of a new graphite ionization chamber for dosimetry of 60Co beams

    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 60Co 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 cm3. 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 60Co 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 60Co gamma beams. (author)

  16. 60Co accumulation from sediment and planktonic algae by midge larvae (Chironomus luridus)

    This paper reports the results of several experiments carried out to evaluate uptake and retention by a limicolous midge larva of 60Co retained in sediment, either adsorbed on mineral particles or bound to planktonic algae. In order to determine their relative contributions in radionuclide accumulation, the different vectors (water, algae and sediment) were first labelled individually and then simultaneously. 60Co accumulation from water and from algae results in a maximum concentration factor of 30 and in a mean trophic transfer factor of 4·5 × 10−3. The level of contamination of midge larvae from sediment is markedly influenced by the presence of endogenous organic matter. Thus the radionuclide transfer factor is about twice as high for larvae placed in labelled raw sediment than for larvae placed in labelled incinerated sediment, in the presence as in the absence of contaminated planktonic algae. Irrespective of the contamination conditions, 60Co depuration from midge larvae is a very rapid phenomenon that corresponds, in all cases, to a radionuclide half-life of only a few days

  17. A new parallel-plate graphite ionization chamber as a 60Co gamma radiation reference instrument

    The calibration procedure in radiotherapy treatments is very important and a sensitive task due to the high doses delivered to the patients. Generally, the air-kerma cavity standards for 60Co gamma rays are graphite cavity ionization chambers. In this work a new parallel-plate graphite ionization chamber was studied to analyze its potential use as a reference instrument. In order to evaluate its performance in 60Co beams, it was submitted to several characterization tests. Moreover, Monte Carlo simulations were undertaken using the EGSnrc code to study the influence of the chamber components on its response. The results obtained showed that this new ionization chamber presented a satisfactory performance in all evaluated tests. - Highlights: ► A new ionization chamber was characterized as a reference dosimeter for 60Co beams. ► The EGSnrc code was used to determine the influence of the chamber components. ► The characterization test results were within the recommended limits. ► The results showed that this dosimeter may be used as a reference dosimeter

  18. Transfer and mobility of 137 Cs and 60 Co in oxisol and alfisol

    One manner to assess potential mobility of radionuclides in soils is the use of sequential extraction procedures. These procedures intend to provide the radionuclide partitioning in geochemical phases of soil affected by changes in physico-chemical conditions. In this study a new sequential chemical extraction protocol was choose to evaluate 60 Co and 137 Cs mobility under a large range of physico-chemical soil properties. The results of sequential procedure was further compared with soil to plant transfer factors data for maize and radish and with soil properties, showing rather consistent results. The 137 Cs distribution in soil showed that Fe oxides are the main sink for this element and after 14 years after contamination the 137 Cs was still available for plants. The 60 Co distribution showed that Mn oxides are the main sink for this element in Alfisol and 5 years after contamination no 60 Co was detected as bioavailable neither detectable in maize. The knowledge of the bio-geochemical behavior of radionuclides in soil system can be useful for risk assessment studies, to be applied in the case of nuclear accident or contamination scenarios. (author)

  19. Leaching of 60Co, 137Cs and 226Ra in lysimeter experiments

    The present report describes the first results obtained from lysimeter experiments started in 1990. The lysimeter plant consists of twelve soil monoliths from four different sites (three replicates each). Since 1990 the following agricultural crops were grown: endive, corn, winter wheat, mustard, sugar beet and potato. Gravitational water ranged from 3.9 % to 18.3 % of precipitation plus irrigation water, calculated as half years average values excluding the first six months of operation. The two Cambisols on sediments exhibited a mean percentage of approx. 10 %. The Dystric Cambisol on silicate rock and the Gleysol showed average values of 20 %. In 1990 the top layers (20 cm) were contaminated with three radionuclides. The leaching of the contaminants 60Co, 137Cs and 226Ra differed distinctly between the elements. The lowest leaching rates were observed for 137Cs, followed by 60Co. The 226Ra-concentrations in the gravitational water were clearly highest of all. However, the comparison of the 226Ra/2228Ra ratios in deep soil layers and in gravitational water showed that the 226Ra measured in the leachate originates from the natural contents in the subsoil and not from the artificial 226Ra contamination of the topsoil. The mobility of the artificial radionuclides decreased therefore in the following order: 60Co > (226Ra) > 137Cs. (author)

  20. Effects of 60Co γ-radiation on the embryo development of goldfish

    The effects of 60Co γ-radiation on the development of goldfish embryos were investigated by different doses and different dose rate. The results showed that 0.5-1.0 Gy 60Co γ-radiation could speed up the development of embryos, but did not cause higher hatching rate. 0.5-1.0 Gy 60Co γ-radiation caused hyperradiosensitivity on goldfish embryos, whereas 2.0-4.0 Gy caused increased radioresistance. Embryos at 4-8 cell stage showed higher survival rate and lower abnormal embryo rate than embryos at multicellular stage or early gastrula stage when radiated at the same dose and dose rate. The results also showed that the radiation at low dose rate (lower than 1.0 Gy/min) could cause more serious damage than the relative higher dose rate (1.0 Gy/min). Early embryos radiated at 1.0 Gy/min dose rate and lower than 2.5 Gy were suggested for the breeding. (authors)

  1. Effects of {gamma} ({sup 60}Co) and {beta} ({sup 90}Sr) radiations in Chinese hamster ovarian cells (CHO-K1): induction of micronuclei and cell death; Efeitos das radiacoes {gamma} ({sup 60}Co) e {beta} ({sup 90}Sr) em celulas de ovario de hamster chines (CHO-K1): inducao de micronucleos e morte celular

    Murakami, Daniella

    2003-07-01

    Among various types of ionising radiation, the beta emitter radionuclides are involved in many sectors of human activity, such as nuclear medicine, nuclear industries and biomedicine, with a consequent increased risk of accidental, occupational or therapeutic exposure. Despite their recognized importance, there is little information about the effect of beta particles at the cellular level when compared to other types of ionizing radiation. Thus, the objective of the present study was to evaluate the genotoxic and cytotoxic effects of {sup 90}Sr, a pure, highly energetic beta source, on CHO-K1 cells and to compare them with data obtained with {sup 60}Co. CHO-K1 cells irradiated with different doses (1.0, 2.5, 5.0, 7.5 Gy) of {sup 60}Co (0.34 Gy.min{sup -1}) and {sup 90}Sr (0.23 Gy.min{sup -1}) were processed for analysis of clonogenic death, induction of micronuclei (MN) and necrotic and apoptotic death. The survival curves obtained for both types of radiation were better fitted by the linear-quadratic model and were similar. However, the cytogenetic results showed that both the proportion of micronucleated cells and the magnitude of radioinduced lesions demonstrated by the analysis of MN distribution were significantly higher in cells irradiated with {sup 60}Co than in cells irradiated with {sup 90}Sr, whereas {sup 90}Sr was more damaging than {sup 60}Co in terms of cell death induction. Necrosis was the major type of death observed in CHO-K1 cells. The data obtained suggest that the low incidence of micronucleated cells after exposure to {sup 90}Sr may be a consequence of selective elimination of severely damaged cells from the population by the necrotic process at a higher rate than observed with {sup 60}Co exposure. The data obtained also demonstrated the need to use several parameters for a better estimate of cellular sensitivity to the action of genotoxic agents, which would be important in terms of radiobiology, oncology and therapeutics. (author)

  2. Expression changes of human mitochondrial COX genes in human lymphocytes after exposed by 60Co γ-rays

    Objective: To explore the changes of human mitochondrial COX Ⅰ , COX Ⅱ and COX Ⅲ genes expression induced by ionizing irradiation. Methods: Changes of human COX genes expression were detected by RT-PCR and Real-time PCR 8 h after the irradiation in human lymphoblastoid cell lines,which were exposed to 1-10 Gy 60Co γ-rays. The protein levels were detected by flow cytometry and the COX activity was measured by colorimetry. The dose-effect relationships between the expression changes of the genes and the doses were established. The changes of these genes expression were also analyzed at different post-radiation time-points between 0.5 h and 72 h after irradiation of 5 Gy in order to explore the time-effect. Results: The expression of 3 genes at mRNA level was up-regulated. A good dose-effect relationship was showed for COXⅠ and COX Ⅲ at dose range of 0-3 Gy and 0-8 Gy for COX Ⅱ (FCOXⅠ=116. 62, FCOXⅡ=17. 89, FCOXⅢ = 8.20, P<0.05). For the time-effect after irradiation, the gene expression levels of COX Ⅱ and COX Ⅲ genes were up-regulated and the peak change occurred at 4 h after irradiation. For COX Ⅰ gene, the mRNA expression levels were down-regulated during 0.5-72 h (FCOXⅠ=31.99, FCOXⅡ=19.47, FCOXⅢ=20.64, P<0.05 ). At the protein level, the levels of COX Ⅰ and COX Ⅱ were lowered in lower doses and enhanced in higher doses, and the levels of COX Ⅲ were decreased at all dose levels (FCOXⅠ=16.96, FCOXⅡ=32.5, FCOXⅢ=6.51, P<0.05). The protein levels of COX Ⅰ and COX Ⅱ were enhanced during 4-72 h and 8-72 h respectively after 5 Gy irradiation (FCOXⅠ=14.68,FCOXⅡ=17.18, FCOXⅢ =2.52, P<0.05). The activities of COX were lowered at different dose levels and different time-points. Conclusions: Ionizing radiation might induce the changes in mitochondrial COX Ⅰ, COX Ⅱ and COX Ⅲ gene expression, and lead to the reduction of the COX activities. (authors)

  3. 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

    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)

  4. Dose-dependent pattern of inducible mRNA expression of PIG3 gene in normal human lymphoblastoid cells by 60Co γ-rays

    Objective: To investigate the dose-response pattern on the inducible expression of PIG3 mRNA in normal human lymphoblastoid AHHI cells by 60Co γ-rays, and its possibility for developing novel radiation biodosimeter. Methods: Laser confocal fluorescent microscopy was used to detect the γ-H2AX foci, a biomarker of DNA double-strand break. After irradiation with 0, 1, 2, 4, 6, 8 and 10 Gy of 60Co γ- rays, AHH-1 cells were harvested at 4, 10 and 24 h post-irradiation, and subjected to total RNA extraction and detection of PIG3 mRNA expression by quantitative real-time PCR. Results: PIG3 protein foci were formed in the nuclei at 30 min after irradiation, and a part of these PIG3 foci were colocalized with γH2AX foci. After irradiation, PIG3 mRNA level was enhanced with the increased time of postirradiation, and remained an increased level at least till 24 h. The radiation-inducible expression of PIG3 mRNA was demonstrated in a dose-dependent manner. The dose-dependent range at 4 h post-irradiation was 0-6 Gy, and at 10 h and 24 h was 0-10 Gy. Conclusions: PIG3 involves in the cellular response to DNA double-strand break. The dose-dependent inducible response of PIG3 mRNA expression might provide a valuable candidate for developing a novel radiation biodosimeter. (authors)

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

    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 chain

  6. Ionizing radiation from 60Co and electron accelerator in reducing the population of Salmonella sp. inoculated in chicken meatballs: evaluation of acceptance by consumer

    Salmonella sp. is one of the main microorganisms that causes outbreaks of food borne diseases associated to poultry, and among its derivatives, the chicken meatballs are getting the favorites of the consumer. In the attempt to improve microbiological food safety, a method that has been hardly studied is the irradiation. To study the viability of the use o ionizing radiation originated from 60 Co and electrons accelerator in the reduction of Salmonella sp., frozen chickens meatballs were inoculated with 104 CFU/g of Salmonella sp., with needle and syringe. Subsequently they were exposure to doses of 1.5, 2.0, 2.5 and 3.0 kGy and Salmonella sp. was enumerated. Chicken meatballs were exposed to doses 3.0, 4.0 and 5.0 kGy and submitted to sensory analysis. The gamma radiation from 60CO was effective in the reduction of Salmonella sp. inoculated in chicken meatballs. The ionizing radiation originated from electron beam was not effective in the conditions applied in this research. The commercial chicken meatballs prepared with chicken meat, mixed up with soy protein, seasoning and anti-oxidants additives did not loose their sensorial quality when exposure to doses of 3.0, 4.0 and 5.0 kGy and, in a general way, the consumers showed to be disposed to buy the irradiation product (author)

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

    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.

  8. The effect of a live Neospora caninum tachyzoite vaccine in naturally infected pregnant dairy cows.

    Mazuz, M L; Fish, L; Wolkomirsky, R; Leibovich, B; Reznikov, D; Savitsky, I; Golenser, J; Shkap, V

    2015-06-15

    Neosporosis, caused by the intracellular protozoan Neospora caninum, is a major cause of abortion and reproductive failure in cattle worldwide. The principal route of transmission of neosporosis is via in utero infection of the offspring. There is no effective prophylactic treatment or vaccine available against bovine neosporosis. A N. caninum NcIs491 isolate was examined for its ability to immunize and reduce abortions in naturally infected dairy cows under field conditions. N. caninum-seropositive pregnant dams were inoculated with 10(8) live tachyzoites during mid-term pregnancy. A total of 520 N. caninum seropositive dams were included in this study, of these, 146 were immunized and 374 cows served as a non-vaccinated control group. A significantly lower incidence of abortion was observed in vaccinated compared to non-vaccinated cows, 16 and 26% respectively (P=0.01), with a vaccine efficacy of 39%. However, the number of seropositive offspring remained similar in both groups. Overall, this field trial suggests that vaccination with live N. caninum tachyzoites should be considered as an effective measure to reduce abortions caused by neosporosis in naturally infected cows. PMID:25890821

  9. Response of the alanine/ESR dosimetry system to MV x-rays relative to 60Co radiation

    The measurand relevant in dosimetry for radiation therapy is the absorbed dose to water, DW. The Physikalisch-Technische Bundesanstalt (PTB) has established a secondary standard for DW for high-energy photon and electron radiation based on electron spin resonance (ESR) of the amino acid alanine. Since the calibration is usually performed using 60Co radiation while a huge part of the external radiation therapy is done with high-energy x-rays from linear accelerators, determination of the response is an important issue. The results presented in this paper are the most accurate ones available today with uncertainties assigned to the relative response for 8 MV and 16 MV of the order of 0.3%. The experimental results are compared to Monte Carlo simulations using the EGSnrc software package. In the appendix, it is demonstrated how mean values from repetitive irradiations and their uncertainties are obtained in a consistent way using Bayesian statistics, even in the presence of at first sight inconsistent data. It is important to note that the formulae derived to obtain the final results follow from first principles, without recurring to ad hoc solutions or simple recipes and are valid for all kinds of repetitive measurements

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

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

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

    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 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 60 Co irradiation blocks the reproductive capacity without affecting the short term viability of tachzoites of T. gondii. (author). 11 refs., 1 fig

  12. 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

    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.

  13. Behavior of the sorption of 60 Co in aqueous solution on inorganic materials as function of p H

    The sorption of the 60 Co is evaluated in aqueous solution on Mg O, MnO2, TiO2, Sn O, activated carbon and hydrotalcite calcined as a function of the p H, using the method for lots and quantifying at the 60 Co for gamma spectrometry. Likewise it was explained the one behavior of the sorption of the 60 Co in the materials with base in the chemical species of this radioactive isotope in aqueous solution. The chemical species of the 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 60 Co showed a significant sorption on MnO2, TiO2 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 60 Co for ion exchange via. It was found that the 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)

  14. Study of the action of 60Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp

    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 60Co 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)

  15. Study of the action of 60Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp

    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 60Co 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)

  16. Assessment of the mobility and bioavailability of 60 Co and 137 Cs in contaminated soils

    Results of a classical sequential chemical extraction procedure for 137 Cs in an acid Oxisol showed that after 3 years of contamination radiocesium remains potentially available for transfer processes: 40% bio-available, 20% mobile under oxidizing conditions and 40% bound to Fe and Mn oxides (available under reducing conditions). At this time, the transfer factor obtained in this soil was higher than values obtained in basic Oxisol and was higher than values obtained in soils from temperate climate areas. Seven years after the contamination, the 137 Cs distribution in this acid Oxisol have been changed as consequence of changes in soil properties: 8% bioavailable, 16% mobile under oxidizing conditions, 43% bound to Fe and Mn oxides and 33% strongly bound to soil compounds. Changes in the 137 Cs distribution in this soil were followed by reductions in soil to plant transfer factor. Between 1996 and 2000, the 137 Cs distribution, 137 Cs soil to plant transfer factor and soil properties in the basic Oxisol remained almost the same. The 60 Co distribution showed that Mn oxides is the main sink for this element and four years after contamination no 60 Co was detected as bioavailable or detectable in plants. In this study the use of an alternative sequential chemical extraction protocol to evaluate 60 Co and 137 Cs mobility under a large range of physico-chemical soil properties has shown to be very consistent with soil to plant transfer factors data for maize. The knowledge of bio-geochemical behavior of radionuclides in soil system can be used for the risk assessment in the case of nuclear accident or contamination scenarios. (author)

  17. 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

    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)

  18. The transfer of 60Co from feed into vitamin B12 in cow liver, milk and beef

    The transfer of the radionuclide 60Co from feed to milk, meat and the organs of a cow and its incorporation into vitamin B12 were studied in order to determine the transfer coefficient of 60Co into vitamin B12 in cattle. Upper limits of transfer coefficients for 60Co organically complexed into vitamin B12 were determined to be 6.0 x 10-5 days/litre in milk and 3.9 x 10-5 days/kg in meat, based on values measured after 140 days in bovine liver. (author)

  19. Assessing deposition levels of 55Fe, 60Co and 63Ni in the Ignalina NPP environment

    Two RBMK-1500 reactor units operated in Lithuania in the 1987-2004 period (one of them was stopped for decommissioning in 2004). This study presents a preliminary investigation of surface deposition density levels of 55Fe and 63Ni in moss samples collected in the close vicinity of the Ignalina NPP. Non-destructive analysis by the HPGe gamma-spectrometry was followed by radiochemical separation. Radiochemical analysis was based on anion-exchange and extraction chromatography. 55Fe and 63Ni activities were measured by liquid scintillation counting (LSC). The results indicate that the deposition values of 55Fe are generally higher than those of 60Co and 63Ni.

  20. Sensitivity of watermelon variety Bojura to mutant agents 60Co and EMS

    Nikolay Velkov; Nasya Tomlekova; Fatma Sarsu

    2016-01-01

    A study on the sensitivity of watermelon variety Bojura to mutagenic agents was carried out in 2013-2014. The goal was to establish effective doses for mutagenic treatment of dry seeds with 60Co gamma rays (80, 100, 200, 250, 350 and 450 Gy) and swollen seeds with water for 24 hours were treated with ethyl methanesulfonate (EMS) at a concentration of 2%. Dominant mutations were not observed in the M1 generation. Morphological changes in 14 of 1395 M2 plants were observed. Phenotypic variation...