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Sample records for lethal dose values

  1. In vitro cell culture lethal dose submitted to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Carolina S.; Rogero, Sizue O.; Rogero, Jose Roberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: carolina_sm@hotmail.com; Ikeda, Tamiko I.; Cruz, Aurea S. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil)

    2009-07-01

    The present study was designed to evaluate the in vitro effect of gamma radiation in cell culture of mouse connective tissue exposed to different doses of gamma radiation and under several conditions. The cell viability was analyzed by neutral red uptake methodology. This assay was developed for establish a methodology to be used in the future in the study of resveratrol radioprotection. Resveratrol (3,4',5- trihydroxystilbene), a phenolic phytoalexin that occurs naturally in some spermatophytes, such as grapevines, in response to injury as fungal infections and exposure to ultraviolet light. In the wines this compound is found at high levels and is considered one of the highest antioxidant constituents. The intense antioxidant potential of resveratrol provides many pharmacological activities including cardioprotection, chemoprevention and anti-tumor effects. Our results demonstrated that {sup 60}Co gamma radiation lethal dose (LD50) on NCTC clone 929 cells was about 340Gy. (author)

  2. In vitro cell culture lethal dose submitted to gamma radiation

    International Nuclear Information System (INIS)

    Moreno, Carolina S.; Rogero, Sizue O.; Rogero, Jose Roberto; Ikeda, Tamiko I.; Cruz, Aurea S.

    2009-01-01

    The present study was designed to evaluate the in vitro effect of gamma radiation in cell culture of mouse connective tissue exposed to different doses of gamma radiation and under several conditions. The cell viability was analyzed by neutral red uptake methodology. This assay was developed for establish a methodology to be used in the future in the study of resveratrol radioprotection. Resveratrol (3,4',5- trihydroxystilbene), a phenolic phytoalexin that occurs naturally in some spermatophytes, such as grapevines, in response to injury as fungal infections and exposure to ultraviolet light. In the wines this compound is found at high levels and is considered one of the highest antioxidant constituents. The intense antioxidant potential of resveratrol provides many pharmacological activities including cardioprotection, chemoprevention and anti-tumor effects. Our results demonstrated that 60 Co gamma radiation lethal dose (LD50) on NCTC clone 929 cells was about 340Gy. (author)

  3. Successful Treatment of Acute Lethal Dose of Acrylamide Poisoning

    Directory of Open Access Journals (Sweden)

    Ali Banagozar Mohammadi

    2015-03-01

    Full Text Available Background: Acrylamide (C3H5NO is a vinyl monomer. This water-soluble crystalline solid is a colorless, odorless agent which is used in scientific laboratories and some industries. Acrylamide has cellular oxidative effects. Acute or chronic poisoning with this agent happens as a result of skin, respiratory, or oral contacts. Clinical manifestations depend on the dose, duration, and frequency of contact. Management of these patients consists of conservative and palliative therapies to reduce the oxidative effects. Case: The case was a 29-year-old girl with a Master of Sciences degree in genetics who worked in a university research center with previous history of depression. She had ingested 100cc of 30% Acrylamide solution for intentional suicide attempt. The patient was successfully managed using N-acetyl cysteine, vitamin C, and melatonin. Conclusion: Early diagnosis and appropriate treatment with recommended agents together with supportive therapies can save the life of patients exposed to potentially lethal doses of acrylamide, although intentional or accidental.

  4. Comparative influence of dose rate and radiation nature, on lethality after big mammals irradiation

    International Nuclear Information System (INIS)

    Destombe, C.; Le Fleche, Ph.; Grasseau, A.; Reynal, A.

    1997-01-01

    For the same dose and the 30 days lethality as biological criterion, the dose rate influence is more important than the radiation nature on the results of an big mammals total body irradiation. (authors)

  5. Sterilization and lethal gamma radiation doses on adults and eggs of Sitotroga Cerealella (OLIVIER)

    International Nuclear Information System (INIS)

    Wiendl, F.M.; Bovi, O.A.; Arthur, V.

    1975-04-01

    The influence of lethal doses of radiation from a cobalt 60 gamma source on eggs, adults and fertitility of Sitotroga Cerealella (Olivier) is described. Eggs irradiated with a dose of 14 Krad still showed viability of 16.1%. On longevity doses up to 70 Krad were usually non lethal but some variation could be observed related to the larval diet. Females fertilized by males irradiated with a dose of 70 Krad produced 36% fertile eggs. When the females were irradiated with the same dose, their fertility dropped to 2.2% and when both sexes were irradiated with a 60 Krad dose, the fertility was 28.8%

  6. Frequencies of aneuploidy and dominant lethal mutations in young female mice induced by low dose γ-rays

    International Nuclear Information System (INIS)

    Yao Suyan; Zhang Chaoyang; Dai Lianlian; Gao Changwen

    1991-01-01

    Relationship between aneuploidy, dominant lethal mutations and doses in young feral mice induced by low dose γ-rays was examined. The results suggest that the frequencies of aneuploidy of embryos increased at 0.15 Gy, but increases at over 0.50 Gy after irradiation in groups. The frequencies of aneuploidy and dominant lethal mutations increased with increasing doses and fitted linear relationship. This dose-response relationship of trisomic was not significant. The frequency of dominant lethal mutations induced by 60 Co γ irradiation is 5.59%. The effect of dominant lethal mutation is higher than that of the aneuploidy

  7. Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation

    International Nuclear Information System (INIS)

    Vaiman, M.; Guenet, J.-L.; Maas, J.; Nizza, P.

    1966-05-01

    Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of γ radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [fr

  8. Lethal doses of ionizing radiation versus endogenous level of superoxide dismutase

    Energy Technology Data Exchange (ETDEWEB)

    Lipecka, K; Domanski, T; Dniaszewska, K; Grabowska, B; Pietrowicz, D; Lindner, P; Cisowska, B; Gorski, H [Military Medical Academy, Lodz (Poland). Inst. of Occupational Medicine

    1982-06-22

    The stability of superoxide dismutase (SOD) as well as its activity distribution in a human population were investigated. The SOD activity level of the erythrocytes proved to be an index for the endogenous SOD activity in the whole body. In a rat population, having similar SOD frequency distribution as a human population, the mortality due to acute irradiation depended on the SOD level; after a single acute dose approximating the lethal dose (LD/sub 50/30/) the survival depended distinctly on the endogenous SOD activity level.

  9. Lethal dose of gamma radiation for eggs of Corcyra cephalonica (Stainton, 1865) (Lepidoptera: Pyralidae), rice moth

    International Nuclear Information System (INIS)

    Aguilar, J.A.D.; Arthur, V.

    1994-01-01

    The aim of this experiment was to observe the effects of gamma radiation on rice moth Corcyra cephalonica (STAINTON, 1865) eggs. The doses utilized in this experiment were 0; 25; 50; 75; 100; 125; 150; 175; 200 Gy. The experiment was carried out in a climatic room at 25 ± 2 0 C and 70 ± 10% R.H. It was observed that lethal dose LD50 and LD100 for eggs from adults reared by artificial diet were 16 and 75 Gy, respectively. (author). 14 refs, 1 fig, 1 tab

  10. Determination the lethal dose of ascaris lumbricoides ova by gamma irradiation

    CERN Document Server

    Shamma, M A; Sharabi, N

    2002-01-01

    The lethal gamma irradiation dose of ascaris lumbricoides which collected from Damascus Sewage water Plant was determined. Ascaris lumbricoides ova were treated with several gamma irradiation doses with (0.1, 0.2, 0.3, 0.4,...and 1.5 KGy). No morphological changes were observed on the eggs when directly examined microscopically after irradiation. However after two weeks of incubation at 37 degree centigrade the cell contents of the eggs which irradiated with 0.5 KGy and beyond were fragmented and scattered in the whole eggs and no larvae were observed after eight weeks of incubation. It is concluded that the dose 0.5 my be considered as the dose of choice if sewage water is to be treated by gamma rays.

  11. Determination the lethal dose of ascaris lumbricoides ova by gamma irradiation

    International Nuclear Information System (INIS)

    Shamma, M.; Al-Adawi, M.; Sharabi, N.

    2002-11-01

    The lethal gamma irradiation dose of ascaris lumbricoides which collected from Damascus Sewage water Plant was determined. Ascaris lumbricoides ova were treated with several gamma irradiation doses with (0.1, 0.2, 0.3, 0.4,...and 1.5 KGy). No morphological changes were observed on the eggs when directly examined microscopically after irradiation. However after two weeks of incubation at 37 degree centigrade the cell contents of the eggs which irradiated with 0.5 KGy and beyond were fragmented and scattered in the whole eggs and no larvae were observed after eight weeks of incubation. It is concluded that the dose 0.5 my be considered as the dose of choice if sewage water is to be treated by gamma rays. (author)

  12. Caffeine protects mice against whole-body lethal dose of {gamma}-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    George, K.C.; Hebbar, S.A.; Kale, S.P.; Kesavan, P.C. [Biosciences Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    1999-06-01

    Administration of caffeine (1,3,7-trimethylxanthine), a major component of coffee, to Swiss mice at doses of 80 or 100 mg/kg body weight 60 min prior to whole-body lethal dose of {gamma}-irradiation (7.5 Gy) resulted in the survival of 70 and 63% of animals, respectively, at the above doses in contrast to absolutely no survivors (LD-100/25 days) in the group exposed to radiation alone. Pre-treatment with a lower concentration of caffeine (50 mg/kg) did not confer any radioprotection. The protection exerted by caffeine (80 mg/kg), however, was reduced from 70 to 50% if administered 30 min prior to irradiation. The trend statistics reveal that a dose of 80 mg/kg administered 60 min before whole-body exposure to 7.5 Gy is optimal for maximal radioprotection. However, caffeine (80 mg/kg) administered within 3 min after irradiation offered no protection. While there is documentation in the literature that caffeine is an antioxidant and radioprotector against the toxic pathway of radiation damage in a wide range of cells and organisms, this is the first report demonstrating unequivocally its potent radioprotective action in terms of survival of lethally whole-body irradiated mice. (author)

  13. The Hematopoietic Syndrome of the Acute Radiation Syndrome in Rhesus Macaques: A Systematic Review of the Lethal Dose Response Relationship.

    Science.gov (United States)

    MacVittie, Thomas J; Farese, Ann M; Jackson, William

    2015-11-01

    body irradiation (TBI) with 250 kVp or 2 MeV x radiation, Co gamma radiation and reactor- and nuclear weapon-derived mixed gamma: neutron-radiation, delivered at various dose rates from a total body, bilateral, rotational, or unilateral exposure aspect. The DRRs established by a probit analysis vs. linear dose relationship were characterized by two main parameters or dependent variables: a slope and LD50/30. Respective LD50/30 values for studies that used 250 kVp x radiation (five primary studies combined, n = 338), 2 MeV x radiation, Co gamma radiation, and steady-state reactor-derived mixed gamma:neutron radiation for total body uniform exposures were 521 rad [498, 542], 671 rad [632, 715], 644 rad [613, 678], and 385 rad [357, 413]. The respective slopes were steep and ranged from 0.738 to 1.316. The DRR, LD50/30 values and slopes were also determined for total body, non-uniform, unilateral, pulse-rate exposures of mixed gamma:neutron radiation derived at reactor and nuclear weapon detonations. The LD50/30 values were, respectively, 395 rad [337, 432] and 412 rad [359, 460]. Secondary data sets of limited studies that did not describe a DRR were used to support the mid-to-high lethal dose range for the H-ARS and the threshold dose range for the concurrent acute GI ARS. The available evidence provided a reliable and extensive database that characterized the DRR for the H-ARS in young rhesus macaques exposed to 250 kVp uniform total body x radiation without the benefit of medical management. A less substantial but consistent database demonstrated the DRR for total body exposure of differing radiation quality, dose rate and non-uniform exposure. The DRR for the H-ARS is characterized by steep slopes and relative LD50/30 values that reflect the radiation quality, exposure aspect, and dose rate over a range in time from 1954-2012.

  14. Derangement of cellular plasma membranes due to non-lethal radiation doses

    International Nuclear Information System (INIS)

    Koeteles, G.J.; Kubasova, T.; Somosy, Z.; Horvath, L.

    1983-01-01

    Earlier observations in the laboratory on fibroblasts and various blood cells of animal and human origins pointed to alteration of concanavalin A binding sites of plasma membranes as well as to concomitant morphological changes and scanning electron microscopic appearance of cell surfaces following sub-lethal doses of X-, fission neutron and beta irradiations. The effects appeared early and existed temporarily; their intensities and the restitution of membrane function depended on radiation doses, types and conditions of cells. In the present paper further aspects of structural and functional derangements of plasma membranes are introduced which were provoked by X- and tritium beta irradiation in the dose range up to 2.5 Gy and in the concentration range from 3.7 kBq/mL, respectively. The state of membrane structure was followed by bindings of various ligands of different receptor requirements, concanavalin A, cationized ferritin and polio virus. In the case of X-irradiation the binding conditions suggest the shift of overall negative surface charges to less negative ones. It was also found that radiation-induced phenomena appear on the cell surface unevenly. Long- and short-term treatments of cells with 3 H-thymidine and 3 H-water also perturb the plasma membrane; beta irradiation affects it directly. Membrane structure and function are suggested to offer good biological models to study correlation of energy deposition and biological effects, both restricted to domains of nanometre range. The data give evidence for radiation-induced membrane alterations in the sub-lethal or non-lethal ranges which might have consequences in the development of stochastic and non-stochastic effects. (author)

  15. Influence of radioprotectors on total body weight evolution and on oxygen consumption in lethal dose irradiated animals. (Preliminary study)

    International Nuclear Information System (INIS)

    Fatome, M.; Martine, G.; Bargy, E.; Andrieu, L.

    Comparison of total body weight evolution and oxygen consumption in lethal dose irradiated animals, protected by various well known radioprotective substances, isolated or in mixture, with evolution and consumption of non protected animals irradiated at the same dose and with these of check animals [fr

  16. Chloroquine Improves Survival and Hematopoietic Recovery After Lethal Low-Dose-Rate Radiation

    International Nuclear Information System (INIS)

    Lim Yiting; Hedayati, Mohammad; Merchant, Akil A.; Zhang Yonggang; Yu, Hsiang-Hsuan M.; Kastan, Michael B.; Matsui, William; DeWeese, Theodore L.

    2012-01-01

    Purpose: We have previously shown that the antimalarial agent chloroquine can abrogate the lethal cellular effects of low-dose-rate (LDR) radiation in vitro, most likely by activating the ataxia-telangiectasia mutated (ATM) protein. Here, we demonstrate that chloroquine treatment also protects against lethal doses of LDR radiation in vivo. Methods and Materials: C57BL/6 mice were irradiated with a total of 12.8 Gy delivered at 9.4 cGy/hour. ATM null mice from the same background were used to determine the influence of ATM. Chloroquine was administered by two intraperitoneal injections of 59.4 μg per 17 g of body weight, 24 hours and 4 hours before irradiation. Bone marrow cells isolated from tibia, fibula, and vertebral bones were transplanted into lethally irradiated CD45 congenic recipient mice by retroorbital injection. Chimerism was assessed by flow cytometry. In vitro methylcellulose colony-forming assay of whole bone marrow cells and fluorescence activated cell sorting analysis of lineage depleted cells were used to assess the effect of chloroquine on progenitor cells. Results: Mice pretreated with chloroquine before radiation exhibited a significantly higher survival rate than did mice treated with radiation alone (80% vs. 31%, p = 0.0026). Chloroquine administration before radiation did not affect the survival of ATM null mice (p = 0.86). Chloroquine also had a significant effect on the early engraftment of bone marrow cells from the irradiated donor mice 6 weeks after transplantation (4.2% vs. 0.4%, p = 0.015). Conclusion: Chloroquine administration before radiation had a significant effect on the survival of normal but not ATM null mice, strongly suggesting that the in vivo effect, like the in vitro effect, is also ATM dependent. Chloroquine improved the early engraftment of bone marrow cells from LDR-irradiated mice, presumably by protecting the progenitor cells from radiation injury. Chloroquine thus could serve as a very useful drug for protection

  17. Experimental Salmonella typhimurium infections in rats. II. Active and passive immunization as protection against a lethal bacterial dose

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T; Klausen, B

    1990-01-01

    Immunization against a lethal dose of Salmonella typhimurium was studied in athymic and thymus-bearing LEW rats. Active immunization was performed with formalin-killed whole cell vaccine or sublethal infection prior to the lethal infection. After vaccination with killed bacteria the euthymic...... from immunized thymus grafted animals provided only limited protective effect, and treatment with cells from athymic animals had no effect. The study shows that although isogeneic thymus-grafted nude rats become resistent to reinfection with S. typhimurium, only large doses of spleen cells from...

  18. Effect of dose-rate on the frequency of X-linked lethal mutation in the nematode Panagrellus redivivus

    International Nuclear Information System (INIS)

    Ager, D.

    1984-01-01

    A total X-ray dose of 50 Gy was applied to the nematode Panagrellus redivivus using dose-rates ranging from 0.23 Gy/min to 10.49 Gy/min, and the frequency of lethal X-chromosomes was determined. This frequency ranged from approximately 1.6% at the lower dose-rate to 4.3% at the highest dose-rate, indicating a dose-rate dependency of mutation frequency in the spermatogonia and oogonia of this organism. (orig.)

  19. Straightening Beta: Overdispersion of Lethal Chromosome Aberrations following Radiotherapeutic Doses Leads to Terminal Linearity in the Alpha–Beta Model

    Directory of Open Access Journals (Sweden)

    Igor Shuryak

    2017-12-01

    Full Text Available Recent technological advances allow precise radiation delivery to tumor targets. As opposed to more conventional radiotherapy—where multiple small fractions are given—in some cases, the preferred course of treatment may involve only a few (or even one large dose(s per fraction. Under these conditions, the choice of appropriate radiobiological model complicates the tasks of predicting radiotherapy outcomes and designing new treatment regimens. The most commonly used model for this purpose is the venerable linear-quadratic (LQ formalism as it applies to cell survival. However, predictions based on the LQ model are frequently at odds with data following very high acute doses. In particular, although the LQ predicts a continuously bending dose–response relationship for the logarithm of cell survival, empirical evidence over the high-dose region suggests that the survival response is instead log-linear with dose. Here, we show that the distribution of lethal chromosomal lesions among individual human cells (lymphocytes and fibroblasts exposed to gamma rays and X rays is somewhat overdispersed, compared with the Poisson distribution. Further, we show that such overdispersion affects the predicted dose response for cell survival (the fraction of cells with zero lethal lesions. This causes the dose response to approximate log-linear behavior at high doses, even when the mean number of lethal lesions per cell is well fitted by the continuously curving LQ model. Accounting for overdispersion of lethal lesions provides a novel, mechanistically based explanation for the observed shapes of cell survival dose responses that, in principle, may offer a tractable and clinically useful approach for modeling the effects of high doses per fraction.

  20. Priming dose of phenylhydrazine protects against hemolytic and lethal effects of 2-butoxyethanol

    International Nuclear Information System (INIS)

    Palkar, Prajakta S.; Philip, Binu K.; Reddy, Ramesh N.; Mehendale, Harihara M.

    2007-01-01

    Protection against a high dose of a toxicant by prior exposure to another toxicant is called heteroprotection. Our objective was to establish a heteroprotection model in RBCs. Female Sprague Dawley rats treated with an LD90 dose of 2-butoxyethanol (BE, 1500 mg/kg in water, 5 ml/kg po) 14 days after priming with 0.9% NaCl suffered 90% mortality by 15 days, whereas all rats receiving the LD90 dose of BE 14 days after priming with phenylhydrazine (PHZ, 125 mg/kg in 0.9% NaCl, 3 ml/kg po) survived. Hematocrit decreased from normal 45% to 24% by day 3 after PHZ priming and improved thereafter. Increasing the time interval between the priming and LD90 dose to 21 days abolished the heteroprotection. RBCs obtained on days 7 and 14 after PHZ priming unlike those on day 21 were resilient to the hemotoxic metabolite of BE, butoxyacetic acid (BAA). Unaltered hepatic alcohol and aldehyde dehydrogenase activities upon PHZ priming suggested that bioactivation of BE to BAA was unaffected. Lower renal (6 and 12 h) and hepatic (12 h) BAA levels and 3 fold higher excretion of BAA in PHZ-primed rat urine suggested a protective role of toxicokinetics. Higher erythropoietin, reticulocytes, and resiliency of PHZ-primed rat RBCs indicated that newly formed RBCs are resilient to hemolytic BAA. The antioxidant levels in the PHZ-primed rat RBCs did not indicate a protective role in heteroprotection. In conclusion, the resistance of PHZ-primed rats against BE-induced hemotoxicity and lethality is mediated by a combination of altered toxicokinetics, robust erythropoiesis, and resiliency of new RBCs

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  2. Determining lethal dose of gamma radiation on different stages of Tribolium Cosmonauts H b s t

    International Nuclear Information System (INIS)

    Zolfagharieh, H.R.; Majd, F.; Torshyzie, M.; Babaie, M.

    1992-10-01

    Pest infestation causes great losses to stored grain through out the world. This is specially true in developing countries where the technology is less advanced, and climatic conditions are extremely favourable for the development of pests. Irradiation is on approved method of direct control for stored-product insect in wheat and wheat flour in many countries, and in dictation are that it will soon be approved for all grain, grain products and other dry food commodities. Radiation doses required to kill or sterilized the most important storage pests in all stages are known. However irradiation is very effective in preventing insect development and in producing sterility. A detailed analysis of the radiosensitivity of stored-product insects shows the different groups of pests have very different sensitivities and quarantine doses can be tailored to kill or sterilize the species of quarantine concern. The effect of irradiation on insects are many, and varied, depending primarily on the species, stage, age and physical factors. The aim is to survey the effect of gamma radiation on stored pest, which can categorized under following classes: 1-The effect of gamma radiation on different stages grow of tribolium castaneum (H B S T); 2-Determination of lethal doses.; 3-The study of gamma radiation on products. In summary these information indicated that fairly low dosages of gamma radiation could be used on commodities such as bulk grain in which some infestation by insect stages of irradiation would be required on products such package foods where hundred percent mortality must be obtain. (author)

  3. Determination of gamma radiation lethal dose (LD50) and resveratrol cytotoxicity level in tumor cells line

    International Nuclear Information System (INIS)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R.; Cruz, Aurea S.

    2011-01-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD 50 ) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC 50% in NCI-H292 cells was 192μM and in RD cells was 128μM; and RD cells gamma radiation LD 50 was 435Gy. (author)

  4. The effects of radiation dose-rate and quality on the induction of dominant lethals in mouse spermatids

    International Nuclear Information System (INIS)

    Searle, A.G.; Beechey, G.V.

    1981-01-01

    Hybrid male mice were given 3 Gy (300 rad) doses of X- or γ-irradiation at dose-rates of either 0.6 or 0.002 Gy/min for each radiation. Germ-cells treated as spermatids were tested for dominant lethality. Effects on spermatogonia were evaluated by studying testis-weight, sperm-count and sperm abnormalities. The rate of induction of dominant lethal mutations was 2.1 times as high after acute X-irradiation as after protracted γ-irradiation. Most of this difference resulted from the change in radiation quality, since the relative effectiveness of X- versus γ-irradiation was 1.9 at low and 1.6 at high dose rates. For each radiation, however, fewer dominant lethals were induced at low dose-rates than at high (low/high ratios of 0.8 and 0.9 respectively) although differences did not reach a significant level. There were no statistically significant effects of dose rate on testis-weight of sperm-count in the X-ray series, but there were significantly less severe effects on both with protraction of the γ-irradiation. Evidence for effects of radiation quality on these characters was conflicting. Frequencies of abnormal spermatozoa were markedly increased 7 weeks after irradiation but there were no consistent effects of radiation intensity or quality. (orig.)

  5. Effects of lethal dose of γ-irradiation on intestinal enzymes of the pigeons Columba livia intermedia Strickland

    International Nuclear Information System (INIS)

    Gadhia, P.K.

    1979-01-01

    Effect of γ-irradiation with lethal dose (1000 rads) on alkaline phosphatase and glucose-6-phosphatase have been studied in two different regions (duodenum and ileum) of small intestine of pigeons. The enzymes were studied at different intervals like 2, 4, 6 and 8 days after irradiation. The sp. activities of enzyme increased significantly both in duodenum and ileum. However, significant increase in alkaline phosphatase and glucose-6-phosphatase were observed at the 2nd and the 4th days post-irradiation respectively. The increase in enzyme activities may present de novo synthesis of these enzymes after lethal dose of irradiation. The histologic picture revealed that after the 4th day of irradiation, the number of goblet cells increased and after the 6th day crypt-villus system was destroyed completely as compared to sham-irradiated pigeons. (author)

  6. Effects of lethal dose of. gamma. -irradiation on intestinal enzymes of the pigeons Columba livia intermedia Strickland

    Energy Technology Data Exchange (ETDEWEB)

    Gadhia, P.K. (South Gujarat Univ., Surat (India). Dept. of Biosciences); Shah, V.C. (Gujarat Univ. School of Sciences, Ahmedabad (India))

    1979-09-01

    Effect of ..gamma..-irradiation with lethal dose (1000 rads) on alkaline phosphatase and glucose-6-phosphatase have been studied in two different regions (duodenum and ileum) of small intestine of pigeons. The enzymes were studied at different intervals like 2, 4, 6 and 8 days after irradiation. The sp. activities of enzyme increased significantly both in duodenum and ileum. However, significant increase in alkaline phosphatase and glucose-6-phosphatase were observed at the 2nd and the 4th days post-irradiation respectively. The increase in enzyme activities may present de novo synthesis of these enzymes after lethal dose of irradiation. The histologic picture revealed that after the 4th day of irradiation, the number of goblet cells increased and after the 6th day crypt-villus system was destroyed completely as compared to sham-irradiated pigeons.

  7. Sub-Lethal Dose of Shiga toxin 2 from Enterohemorrhagic Escherichia coli Affects Balance and Cerebellar Cythoarquitecture.

    Directory of Open Access Journals (Sweden)

    Luciana eD’Alessio

    2016-02-01

    Full Text Available Shiga toxin producing Escherichia coli may damage the central nervous system before or concomitantly to manifested hemolytic uremic syndrome symptoms. The cerebellum is frequently damaged during this syndrome, however the deleterious effects of Shiga toxin 2 has never been integrally reported by ultrastructural, physiological and behavioral means. The aim of this study was to determine the cerebellar compromise after intravenous administration of a sub-lethal dose of Shiga toxin 2 by measuring the cerebellar blood brain barrier permeability, behavioral task of cerebellar functionality (inclined plane test, and ultrastructural analysis (transmission electron microscope. Intravenous administration of vehicle (control group, sub-lethal dose of 0.5 ηg and 1 ηg of Stx2 per mouse were tested for behavioral and ultrastructural studies. A set of three independent experiments were performed for each study (n=6. Blood–Brain Barrier resulted damaged and consequently its permeability was significantly increased. Lower scores obtained in the inclined plane task denoted poor cerebellar functionality in comparison to their controls. The most significant lower score was obtained after 5 days of 1ηg of toxin administration. Transmission electron microscope micrographs from the Stx2-treated groups showed neurons with a progressive neurodegenerative condition in a dose dependent manner. As sub-lethal intravenous Shiga toxin 2 altered the blood brain barrier permeability in the cerebellum the toxin penetrated the cerebellar parenchyma and produced cell damaged with significant functional implications in the test balance.

  8. The Effect of A Single Sub-Lethal Dose of Whole Body Irradiation on the Small Intestine of Rats

    International Nuclear Information System (INIS)

    Al-Ramli, M. A.; Kubba, M. A.; Al-Bassam, L. S.; Belhaj, K.; Al-shawish, N. M.

    2007-01-01

    The effect of whole body radiation with a single sub-lethal dose at 4 Gy on rat small intestine was studied histologically and quantitatively. Irradiated animals were euthanized at 24 hours, 3, 7, 14, 21 and 28 days post- irradiation. Crypts of Leiberkuhn and peyer's patches were especially targeted by irradiation. The crypts showed severe cellular fragmentation in the germinal cellular compartments twenty Four hours after irradiation resulting in partial denudation of villi especially at their Tips. At three days, these cells resumed their proliferative activity with the appearance of unusually large numbers of mitotic figures. Cellular regeneration in the crypts and on the villous surface showed improvement with advancing time till day 28 when the villi had complete epithelial covering and the proliferative activity of the germinal cryptic cells returned to normal. The quantitative study included the measurement of about fifty villi at each time after irradiation. A significant decrease in villous length was noticed at twenty four hours post-irradiation compared to the control values. The length of villi plateaued at about this level till day twenty one when it slightly increased to reach a sub normal mean length on day 28. We concluded that whole body irradiation with a single dose at 4 Gy was enough to induce cryptic cellular necrosis with sloughing of epithelial villous columnar covering. This cellular damage was, however, sub- total since quick regenerative cellular activity was noticed three days post-irradiation. The decrease in the villous length paralleled the cryptic cellular damage whereas full recovery was not achieved despite obvious cellular regeneration.

  9. Effect of mutagen combined action on Chlamydomonas reinhardtii cells. II. Dependence of lethal effect on mutagen dose and on conditions of cultivation following mutagen action. [In Slovak

    Energy Technology Data Exchange (ETDEWEB)

    Podstavkova, S; Vlcek, D; Dubovsky, J [Komenskeho Univ., Bratislava (Czechoslovakia). Prirodovedecka Fakulta

    1978-01-01

    The effect of UV radiation and UV radiation combined with alkylnitrosourea derivatives (N-methyl-N-nitrosourea and N-ethyl-N-nitrosourea) was observed on survival of cells of the algae Chlamydomonas reinhardtii. In particular, single parts were evaluated of the overall lethal effect - dying of cells before division and dying of cells after division. It was found that the combined action of low doses of UV radiation and alkylnitrosoureas result in a pronounced protective effect which manifests itself by a higher frequency of surviving cells than was that effected by the action of alkylnitrosoureas alone. As a result of combined action with higher doses of UV radiation this effect is lost, and the resultant values will come close to the theoretically anticipated values. This gradual transition from a protective to an additive effect mainly manifests itself by changes in the proportion of cells dying before division.

  10. Protection of lethally irradiated mice with allogeneic fetal liver cells: influence of irradiation dose on immunologic reconstitution

    International Nuclear Information System (INIS)

    Tulunay, O.; Good, R.A.; Yunis, E.J.

    1975-01-01

    After lethal irradiation long-lived, immunologically vigorous C3Hf mice were produced by treatment with syngeneic fetal liver cells or syngeneic newborn or adult spleen cells. Treatment of lethally irradiated mice with syngeneic or allogeneic newborn thymus cells or allogeneic newborn or adult spleen cells regularly led to fatal secondary disease or graft-versus-host reactions. Treatment of the lethally irradiated mice with fetal liver cells regularly yielded long-lived, immunologically vigorous chimeras. The introduction of the fetal liver cells into the irradiated mice appeared to be followed by development of immunological tolerance of the donor cells. The findings suggest that T-cells at an early stage of differentiation are more susceptible to tolerance induction than are T-lymphocytes at later stages of differentiation. These investigations turned up a perplexing paradox which suggests that high doses of irradiation may injure the thymic stroma, rendering it less capable of supporting certain T-cell populations in the peripheral lymphoid tissue. Alternatively, the higher and not the lower dose of irradiation may have eliminated a host cell not readily derived from fetal liver precursors which represents an important helper cell in certain cell-mediated immune functions, e.g., graft-versus-host reactions, but which is not important in others, e.g., allograft rejections. The higher dose of lethal irradiation did not permit development or maintenance of a population of spleen cells that could initiate graft-versus-host reactions but did permit the development of a population of donor cells capable of achieving vigorous allograft rejection

  11. Insect radiosensitivity: dose curves and dose-fractionation studies of dominant lethal mutations in the mature sperm of 4 insect species

    International Nuclear Information System (INIS)

    LaChance, L.E.; Graham, C.K.

    1984-01-01

    Males of 4 species of insects: Musca domestica L. (housefly) (Diptera), Oncopeltus fasciatus (Dallas) (milkweed bug) (Hemiptera), Anagasta kuhniella (Zeller) (mealmoth) (Lepidoptera) and Heliothis virescens (Fab.) (tobacco budworm) (Lepidoptera) were irradiated as adults. Dose-response curves for the induction of dominant lethal mutations in the mature sperm were constructed. The curves were analyzed mathematically and compared with theoretical computer simulated curves requiring 1, 2, 4, 8 and 16 'hits' for the induction of a dominant lethal mutation. The 4 species belonging to 3 different orders of insects showed a wide range in radiation sensitivity and vastly different dose-response curves. When the data were analyzed by several mathematical models the authors found that a logistic response curve gave reasonably good fit with vastly different parameters for the 4 species. Dose-fractionation experiments showed no reduction in the frequency of lethal mutations induced in any species when an acute dose was fractionated into 2 equal exposures separated by an 8-h period. (Auth.)

  12. Importance of dose metrics for lethal and sublethal sediment metal toxicity in the oligochaete worm Lumbriculus variegatus

    Energy Technology Data Exchange (ETDEWEB)

    Penttinen, O.P.; Kilpi-Koski, J.; Toivainen, K. [Helsinki Univ., Lahti (Finland). Dept. of Ecology end Environmental Sciences; Jokela, M. [Mikkeli Univ. of Applied Sciences, Mikkeli (Finland); Vaeisaenen, A. [Jyvaeskylae Univ. (Finland). Dept. of Chemistry

    2008-02-15

    Background, aims, and scope. There is an increasing demand for controlled toxicity tests to predict biological effects related to sediment metal contamination. In this context, questions of metal-specific factors, sensitivity of toxicity endpoints, and variability in exposure duration arise. In addition, the choice of the dose metrics for responses is equally important and is related to the applicability of the concept of critical body residue (CBR) in exposure assessments, as well as being the main focus of this study. Methods. Experiments were conducted to assess toxicity of Cd, Cr, Cu and Pb to the oligochaete worm Lumbriculus variegatus with the aim of determining CBRs for two response metrics. Mortality and feeding activity of worms exposed to sediment-spiked metals were used as end-points in connection with residue analyses from both the organisms and the surrounding media. Results. LC50 values were 0.3, 1.4, 5.2, and 6.7 mg/L (from 4.7 {mu}mol/L to 128.0 {mu}mol/L), and the order of toxicity, from most toxic to least toxic, was Cu > Cd > Pb>Cr. By relating toxicity to body residue, variability in toxicity among the metals decreased and the order of toxicity was altered. The highest lethal residue value was obtained for Cu (10.8 mmol/kg) and the lowest was obtained for Cd (2.3 mmol/kg). In the 10-d sublethal test, both time and metal exposure were an important source of variation in the feeding activity of worms. The significant treatment effects were observed from worms exposed to Cd or Pb, with the controls yielding the highest feeding rate. However, quantitative changes in the measured end-point did not correlate with the exposure concentrations or body residues, which remained an order of magnitude lower than in the acute exposures. (orig.)

  13. Comparative studies of dose-response curves for recessive lethal mutations induced by ethylnitrosourea in spermatogonia and in spermatozoa of Drosophila melanogaster

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, I.; Ayaki, T.; Ohshima, K.

    1984-01-01

    Induction of recessive lethal mutation by N-ethyl-N-nitrosourea (ENU) was studied for the second chromosome of spermatogonia and spermatozoa in Drosophila melanogaster. ENU (0.03, 0.3, and 1.0 mM) was given to flies by dissolving it in feeding sucrose solution. When plotted against absorbed doses of ENU, the observed frequencies to recessive lethals showed a linear relationship for induction in spermatozoa but a sigmoidal relationship for induction in spermatogonia. These results suggest that in spermatogonia ENU-induced mutational damage is more repairable in a lower dose range of ENU. Mosaic lethal mutations were induced by ENU but not in spermatogonia.

  14. Determination of the Median Lethal Dose and Electrophoretic Pattern of Hottentotta saulcyi (Scorpiones, Buthidae Scorpion Venom

    Directory of Open Access Journals (Sweden)

    ErsenAydın Yağmur

    2015-10-01

    Full Text Available Background: In this study, we investigated the lethal potency, electrophoretic protein pattern and in vivo effects of Hottentotta saulcyi scorpion venom in mice.Methods: Scorpions were collected at night, by using a UV lamp from Mardin Province, Turkey. Venom was obtained from mature H. saulcyi scorpions by electrical stimulation of the telson. The lethality of the venom was determined by i.v. injections using Swiss mice. In vivo effects of the venom were assessed by using the intraperitoneal route (ip injections into mice (20±1g and monitored for 24 h. The protein profiles of the scorpion venom were analyzed by NuPAGE® Novex® 4–12 % gradient Bis-Tris gel followed by Coomassie blue staining.Results: The lethal assay of the venom was 0.73 mg/kg in mice. We determined the electrophoretic protein pattern of this scorpion venom to be 4, 6, 9, 31, 35, 40, 46 and 69 kDa by SDS-PAGE. Analysis of electrophoresis indicated that H. saulcyi scorpion intoxicated mice exhibited autonomic nervous system symptoms (tachypnea, restlessness, hyperexcitability, convulsions, salivation, lacrimation, weakness.Conclusions: Hottentotta saulcyi scorpion venom includes short-chain neurotoxins and long-chain neurotoxins according to the electrophoretic protein patterns. The stings of H. saulcyi scorpion must be considered of risk for humans in the southeastern region, Turkey.

  15. Changes in electrographic correlates of sleep-wakefulness cycle in cats irradiated with minimal lethal doses

    International Nuclear Information System (INIS)

    Kordzadze, R.N.; Nadarishvili, K.Sh.; Tsinitia, K.A.

    1983-01-01

    The paper deals with the dynamics of changes in bioelectrical activity (BEA) of the somatosensory cortex (SC) and dorsal hippocampus (DH) in the sleep-wakefulness (SW) cycle by means of a computer and automatized frequency analysis system in the course of chronic experiences with cats before and at various stages of development of radiation sickness (RS). The dose of single whole-body irradiation equaled 8 Gr (800+-20 rad). It has been shown that changes which occur in SC substantially differ in dependence on the stages of the SW cycle. More pronounced changes after irradiation are observed in low-frequency rhythms, particularly at the stage of deep slow wave sleep (DSWS) and less pronounced - in the paradoxical sleep (PS). Rhythmics shifts taking place in DH are mainly similar during wakefulness (W), superficial slow wave sleep (SSWS) and DSWS. In PS changes in rhythmics considerably differ as compared with We SSWS and DSWS. Revealed are also other specific shifts including a reliable enhancement of absolute value (AV) and specific ponderability (SP) of thera-rhythm of hippocampus during the RS acute period in animals survived the three week observation period. All this permits to conclude that BEA quantitative studies of various brain areas in the SW permit to reveal the trends in search of diagnostic and prognostic value of such investigations in case of different extreme states and to outline on the patogenetic basis correction methods for neutral disorders in case of RS

  16. Exome sequencing for gene discovery in lethal fetal disorders--harnessing the value of extreme phenotypes.

    Science.gov (United States)

    Filges, Isabel; Friedman, Jan M

    2015-10-01

    Massively parallel sequencing has revolutionized our understanding of Mendelian disorders, and many novel genes have been discovered to cause disease phenotypes when mutant. At the same time, next-generation sequencing approaches have enabled non-invasive prenatal testing of free fetal DNA in maternal blood. However, little attention has been paid to using whole exome and genome sequencing strategies for gene identification in fetal disorders that are lethal in utero, because they can appear to be sporadic and Mendelian inheritance may be missed. We present challenges and advantages of applying next-generation sequencing approaches to gene discovery in fetal malformation phenotypes and review recent successful discovery approaches. We discuss the implication and significance of recessive inheritance and cross-species phenotyping in fetal lethal conditions. Whole exome sequencing can be used in individual families with undiagnosed lethal congenital anomaly syndromes to discover causal mutations, provided that prior to data analysis, the fetal phenotype can be correlated to a particular developmental pathway in embryogenesis. Cross-species phenotyping allows providing further evidence for causality of discovered variants in genes involved in those extremely rare phenotypes and will increase our knowledge about normal and abnormal human developmental processes. Ultimately, families will benefit from the option of early prenatal diagnosis. © 2014 John Wiley & Sons, Ltd.

  17. Dose-response tests and semi-field evaluation of lethal and sub-lethal effects of slow release pyriproxyfen granules (Sumilarv®0.5G) for the control of the malaria vectors Anopheles gambiae sensu lato.

    Science.gov (United States)

    Mbare, Oscar; Lindsay, Steven W; Fillinger, Ulrike

    2013-03-14

    Recently research has shown that larviciding can be an effective tool for integrated malaria vector control. Nevertheless, the uptake of this intervention has been hampered by the need to re-apply larvicides frequently. There is a need to explore persistent, environmentally friendly larvicides for malaria vector control to reduce intervention efforts and costs by reducing the frequency of application. In this study, the efficacy of a 0.5% pyriproxyfen granule (Surmilarv®0.5G, Sumitomo Chemicals) was assessed for the control of Anopheles gambiae sensu stricto and Anopheles arabiensis, the major malaria vectors in sub-Saharan Africa. Dose-response and standardized field tests were implemented following standard procedures of the World Health Organization's Pesticide Evaluation Scheme to determine: (i) the susceptibility of vectors to this formulation; (ii) the residual activity and appropriate retreatment schedule for field application; and, (iii) sub-lethal impacts on the number and viability of eggs laid by adults after exposure to Sumilarv®0.5G during larval development. Anopheles gambiae s.s. and An. arabiensis were highly susceptible to Sumilarv®0.5G. Estimated emergence inhibition (EI) values were very low and similar for both species. The minimum dosage that completely inhibited adult emergence was between 0.01-0.03 parts per million (ppm) active ingredient (ai). Compared to the untreated control, an application of 0.018 ppm ai prevented 85% (95% confidence interval (CI) 82%-88%) of adult emergence over six weeks under standardized field conditions. A fivefold increase in dosage of 0.09 ppm ai prevented 97% (95% CI 94%-98%) emergence. Significant sub-lethal effects were observed in the standardized field tests. Female An. gambiae s.s. that were exposed to 0.018 ppm ai as larvae laid 47% less eggs, and females exposed to 0.09 ppm ai laid 74% less eggs than females that were unexposed to the treatment. Furthermore, 77% of eggs laid by females exposed to 0

  18. Relative effect of radiation dose rate on hemopoietic and nonhemopoietic lethality of total-body irradiation

    International Nuclear Information System (INIS)

    Peters, L.J.; McNeill, J.; Karolis, C.; Thames, H.D. Jr.; Travis, E.L.

    1986-01-01

    Experiments were undertaken to determine the influence of dose rate on the toxicity of total-body irrdiation (TBI) with and without syngeneic bone-marrow rescue in mice. The results showed a much greater dose-rate dependence for death from nonhemopoietic toxicity than from bone-marrow ablation, with the ratio of LD 50 's increasing from 1.73 at 25 cGy/min to 2.80 at 1 cGy/min. At the higher dose rates, dose-limiting nonhemopoietic toxicity resulted from late organ injury, affecting the lungs, kidneys, and liver. At 1 cGy/min the major dose-limiting nonhemopoietic toxicity was acute gastrointestinal injury. The implications of these results in the context of TBI in preparation for bone-marrow transplantation are discussed. 15 refs., 4 figs

  19. Lethal dose determination of Cobalt-60 for adult Tribolium castaneum (Coleoptera: Tenebrionidae) and Cryptolestes ferrugineus (Coleoptera: Laemophloeidae)

    International Nuclear Information System (INIS)

    Farias, Anderson Aparecido; Potenza, Marcos Roberto; Reis, Fabricio Caldeira; Sato, Mario Eidi

    2015-01-01

    The insect infestation is a major problem in the grain storage. The pesticides are most widely used method for disinfestation and prevention. Treatment with gamma irradiation may increase the product shelf life without encountering formation of waste can be used in packaged foods and ready for commercialization, representing an important alternative to the use of pesticides. This study aimed to determine the immediate lethal dose of gamma radiation for adults of Tribolium castaneum and Cryptolestes ferrugineus. The study was conducted in the Instituto Biologico and the radiations held at the Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN, Sao Paulo city, using a multipurpose irradiator Cobalt-60 with 3.31 dose rate and 3.23 kGy in months of November/2014 and January/2015. Each experimental unit consisted of 20 adult insects, confined in a 10 mL polyethylene container. The experimental plots in number 10 per dose were subjected to increasing doses of gamma radiation: 0; 0.5; 0.75; 1.0; 1.25; 1.50; 1.75; 2.00; 2:50 and 3.00 kGy. Mortality was assessed within two to four hours after irradiation. The data were submitted to Probit analysis, using the POLO PLUS program. The LD90 to control 90% (LD90) to control adult Cryptolestes ferrugineus and Tribolium castaneum were 2.73 and 2.91 kGy, respectively. (author)

  20. Lethal dose determination of Cobalt-60 for adult Tribolium castaneum (Coleoptera: Tenebrionidae) and Cryptolestes ferrugineus (Coleoptera: Laemophloeidae)

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Anderson Aparecido, E-mail: potenza@biologico.sp.gov.br [Instituto Biologico, Centro de Pesquisa e Desenvolvimento de Protecao Ambiental, Sao Paulo, SP (Brazil); Potenza, Marcos Roberto, E-mail: fcreis@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Reis, Fabricio Caldeira; Sato, Mario Eidi, E-mail: mesato@biologico.sp.gov.br [Instituto Biologico, Centro Experimental Central, Laboratorio de Acarologia, Campinas, SP (Brazil)

    2015-07-01

    The insect infestation is a major problem in the grain storage. The pesticides are most widely used method for disinfestation and prevention. Treatment with gamma irradiation may increase the product shelf life without encountering formation of waste can be used in packaged foods and ready for commercialization, representing an important alternative to the use of pesticides. This study aimed to determine the immediate lethal dose of gamma radiation for adults of Tribolium castaneum and Cryptolestes ferrugineus. The study was conducted in the Instituto Biologico and the radiations held at the Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN, Sao Paulo city, using a multipurpose irradiator Cobalt-60 with 3.31 dose rate and 3.23 kGy in months of November/2014 and January/2015. Each experimental unit consisted of 20 adult insects, confined in a 10 mL polyethylene container. The experimental plots in number 10 per dose were subjected to increasing doses of gamma radiation: 0; 0.5; 0.75; 1.0; 1.25; 1.50; 1.75; 2.00; 2:50 and 3.00 kGy. Mortality was assessed within two to four hours after irradiation. The data were submitted to Probit analysis, using the POLO PLUS program. The LD90 to control 90% (LD90) to control adult Cryptolestes ferrugineus and Tribolium castaneum were 2.73 and 2.91 kGy, respectively. (author)

  1. Effects of sub-lethal dose of γ-irradiation on lysosomal enzymes in tissue of pigeon

    International Nuclear Information System (INIS)

    Shah, V.C.; Gadhia, P.K.

    1979-01-01

    Effects of total body γ-irradiation with sub-lethal dose (300 rad) on three lysosomal enzymes namely acid phosphatase, ribonuclease-II and deoxyribonuclease-II have been studied in pigeons. Liver, kidney and spleen were the tissues studied at different intervals like 1-h, 24-h, 48-h, and 72-h of irradiation. The specific activities ('crude' fraction) of acid phosphatase and ribonuclease-II increased significantly in spleen and liver at 48-h of irradiation. The activity of deoxyribonuclease-II in liver and spleen was increased only at 72-h post-irradiation. On the other hand, the total activities of three lysosomal enzymes did not show remarkable change throughout 72-h of irradiation. (author)

  2. Alternative methods for the median lethal dose (LD(50)) test: the up-and-down procedure for acute oral toxicity.

    Science.gov (United States)

    Rispin, Amy; Farrar, David; Margosches, Elizabeth; Gupta, Kailash; Stitzel, Katherine; Carr, Gregory; Greene, Michael; Meyer, William; McCall, Deborah

    2002-01-01

    The authors have developed an improved version of the up-and-down procedure (UDP) as one of the replacements for the traditional acute oral toxicity test formerly used by the Organisation for Economic Co-operation and Development member nations to characterize industrial chemicals, pesticides, and their mixtures. This method improves the performance of acute testing for applications that use the median lethal dose (classic LD50) test while achieving significant reductions in animal use. It uses sequential dosing, together with sophisticated computer-assisted computational methods during the execution and calculation phases of the test. Staircase design, a form of sequential test design, can be applied to acute toxicity testing with its binary experimental endpoints (yes/no outcomes). The improved UDP provides a point estimate of the LD50 and approximate confidence intervals in addition to observed toxic signs for the substance tested. It does not provide information about the dose-response curve. Computer simulation was used to test performance of the UDP without the need for additional laboratory validation.

  3. The clinic and pathologic picture in the lethal dose irradiated ewes

    International Nuclear Information System (INIS)

    Halagan, J.; Stanikova, A.; Maracek, I.

    2004-01-01

    The history of clinical symptoms as well as pathologic histological and morphological changes after long/lasting gamma irradiation were estimated in seven clinical healthy ewes. The animals were irradiated continually seven days with totally 6.7 Gy per ewe. Clinically recognizable symptoms of the radiation sickness were observed commencing the 4 th after last dose of irradiation. Sharp increase of the body temperature, heart and respiratory frequency rate as well as apathy, anorexia, arrhythmia, dyspnoe, diarrhea, dehydration, polyuria were prevalent in clinical founding . All of the animals were death in course of seven days after last irradiated dose. The gastrointestinal radiation syndrome was typical evidence of gastrointestinal tract and the general hemorrhagic enhancing of the gamma irradiation damage effects was confirmed. (authors)

  4. Productivity and food value of Amaranthus cruentus under non-lethal salt stress

    Science.gov (United States)

    Macler, Bruce A.; Macelroy, Robert D.

    1989-01-01

    Experiments were carried out to analyze the effects of increasing salinity stress on growth, photosynthesis, and carbon allocation in the crop plant Amaranthus. Plants were germinated and grown in Hoagland's solution with NaCl concentrations of 0 to 1.0 percent. The limits of total salinity in the plant growth medium are investigated. For Amaranthus cruentus, germination, vegetative growth, flowering, seed development and yield were normal at salinities from 0 to 0.2 percent. Inhibition of these phases increased from o.2 to 0.4 percent salinity and was total above 0.5 percent with 1 percent salinity was lethal to all developmental phases. Onset of growth phases were not affected by salinity. Plants could not be adapted by gradually increasing salinity over days or weeks. Water uptake increased, while photosynthetic CO2 uptake decreased with increasing salinity on a dry weight basis during vegetative growth. Protein levels were unchanged with increasing salinity. Leaf starch levels were lower at salinities of 0.5 percent and above, while stem starch levels were not affected by these salinities. The evidence supports salt inhibition arising frm changes in primary biochemical processes rather than from effects on water relations. While not addressing the toxic effects of specific ions, it suggests that moderate salinity per se need not be a problem in space systems.

  5. Method and apparatus for determining the dose value of neutrons

    International Nuclear Information System (INIS)

    Burgkhardt, B.; Piesch, E.

    1976-01-01

    A method is provided for determining the dose value of neutrons leaving a body as thermal and intermediate neutrons after having been scattered in the body. A first dose value of thermal and intermediate neutrons is detected on the surface of the body by means of a first detector for neutrons which is shielded against thermal and intermediate neutrons not emerging from the body. A second detector is used to measure a second dose value of the thermal and intermediate neutrons not emerging from the body. A first correction factor based on the first and second values is obtained from a calibration diagram and is applied to the first dose value to determine a first corrected first dose value. 21 Claims, 6 Drawing Figures

  6. On the constitutionality of dose limiting values

    International Nuclear Information System (INIS)

    Goetz, V.

    1976-01-01

    The fundamental right according to Art. 2 par. 2 sentence 1 of the German Constitution is relevant for the set-up and application of radiation protection law. Resulting from Art. 2 par. 2 sentence 1 of the Constitution it is a general obligation of the state to protect life (Federal Constitutional Court, judgment of 25th Feb., 1975, BVerfGE 39.1) and physical soundness. The subjective basic right of everybody to defend against official encroachments his personal integrity corresponds to the right of the individual within the framework of the official obligation for protection from the state (to ward off danger). The term of danger, as to the degree of its determination, corresponds to that of the encroachment. To speak of danger in a legal sense, the causal connection between a certain source of danger and certain damage must be ascertained and proved. Topical controversies as to the admissibility of activity discharges of low doses range in the field of risk reduction and thus in the field of the duty of the state to take precautionary steps against risks (Art. 2 par. 2 sentence 1 of the Constitution). The constitution, however, does not contain any basic right that every risk has to be avoided. On the other hand, the necessity of cautions valuation of radiation risks can be derived from the Constitution. The fixation of dose limits and their application in connection with general radiation protection principles (paragraph 28 E of the Radiation Protection Ordinance) do not contain any 'interference' with the basic right in the sense of Art. 2 par. 2 sentence 3 of the Constitution. Neither from aspects of the principle of the legal state nor from Art. 80 par. 1 of the Constitution can the use of the legal form of the Ordinance be doubted. (orig./HP) [de

  7. Histopathological changes in the kidney of experimental animals caused by lethal doses of thallium

    Energy Technology Data Exchange (ETDEWEB)

    Danilewicz, M; Danilewicz, M; Kurnatowski, A

    1979-01-01

    The experiment was carried out on 65 white male Wistar rats and 65 white male Swiss mice poisoned with thallium sulfate in doses 30 to 40 mg/kg body weight. The animals were sacrificed in the 4, 8, 24, 48th hours of experiment and their kidneys were submitted to light and an electron microscopic examination. With the light microscope necrosis of epithelium of Henle loops, hydropic degeneration, swelling and focal necrosis of epithelium of proximal convoluted tubules, and stromal oedema were seen. An electron microscopic study pointed out swelling and degenerative changes in the mitochondria, loss of microvilli in many cells, dilatation of endoplasmic reticulum and decrease of electron density of basement membranes. Urea level in blood serum and protein level in urine increased.

  8. Establishing Local Reference Dose Values and Optimisation Strategies

    International Nuclear Information System (INIS)

    Connolly, P.; Moores, B.M.

    2000-01-01

    The revised EC Patient Directive 97/43 EURATOM introduces the concepts of clinical audit, diagnostic reference levels and optimisation of radiation protection in diagnostic radiology. The application of reference dose levels in practice involves the establishment of reference dose values as actual measurable operational quantities. These values should then form part of an ongoing optimisation and audit programme against which routine performance can be compared. The CEC Quality Criteria for Radiographic Images provides guidance reference dose values against which local performance can be compared. In many cases these values can be improved upon quite considerably. This paper presents the results of a local initiative in the North West of the UK aimed at establishing local reference dose values for a number of major hospital sites. The purpose of this initiative is to establish a foundation for both optimisation strategies and clinical audit as an ongoing and routine practice. The paper presents results from an ongoing trial involving patient dose measurements for several radiological examinations upon the sites. The results of an attempt to establish local reference dose values from measured dose values and to employ them in optimisation strategies are presented. In particular emphasis is placed on the routine quality control programmes necessary to underpin this strategy including the effective data management of results from such programmes and how they can be employed to optimisation practices. (author)

  9. The effect of sub-lethal doses on the ploidy level in rats hepatocytes with aging

    International Nuclear Information System (INIS)

    Ekhtiar, A. M.

    2004-11-01

    It has been shown that the polyploidization levels in rat's hepatocytes increased with aging. The high LET ionizing radiation also induce cell polyploidization by two different means: cells and nuclei fusion, and mitosis restriction after DNA replication. The purpose of the present study was to determine the kinetic of rat's hepatocytes polyploidization with ageing, and the late effects of low doses of gamma irradiation on polyploidization. To this end, three groups of rats were used. Each group composed of 175 four weeks old animals. The first was served as a control, the second and the third groups were irradiated with 4 and 2 Gy respectively, of gamma irradiation at the age of one month. Of each group, 7-8 animals were monthly scarified (for two years), and their liver tissues were used to obtain cell suspensions which were further fixed in gradual series concentrations of ethanol. After staining with Propidum Iodide 'PI' (10 6 cells per ml of PI used at 10 - 5 M final concentration), the cells were analyzed on a FACS Vantage Flow Cytometer (Becton Dickinson). In the control, the results showed: 1) A decrease of cell fraction that contained normal diploid until steady level. 2) Biphasic changes of fraction tetraploidy cells (increase until age of 4 month followed by decrease). 3) The fraction of octaploidy cells appeared at age of 3-4 month and increased continuously with the aging. In accompanied to life-span reductions of 4 Gy irradiated animals, the DNA contents were similar to those in control groups in addition to some quantities variation due to a programmed cell death (Apoptosis) induced by irradiation and regenerations. These variations persisted till the age of 7 month, in additional to reduce the spin-life of irradiated animals. The irradiation with 2 Gy induced some quantities variation in comparison with nonirradiated group, appeared in the reduction of rate conversion from one ploidy class to another, and in shift with 2-3 months of the second pike

  10. Determination of gamma radiation lethal dose (LD{sub 50}) and resveratrol cytotoxicity level in tumor cells line

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cruz, Aurea S. [Instituto Adolfo Lutz (IAL-SP) Secao de Culturas Celulares, SP (Brazil)

    2011-07-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD{sub 50}) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC{sub 50%} in NCI-H292 cells was 192{mu}M and in RD cells was 128{mu}M; and RD cells gamma radiation LD{sub 50} was 435Gy. (author)

  11. Tityus serrulatus Scorpion Venom: In Vitro Tests and Their Correlation with In Vivo Lethal Dose Assay

    Directory of Open Access Journals (Sweden)

    Daniela Cajado-Carvalho

    2017-11-01

    Full Text Available Scorpion stings are the main cause of human envenomation in Brazil and, for the treatment of victims, the World Health Organization (WHO recommends the use of antivenoms. The first step to achieve effective antivenom is to use a good quality venom pool and to evaluate it, with LD50 determination as the most accepted procedure. It is, however, time-consuming and requires advanced technical training. Further, there are significant ethical concerns regarding the number of animals required for testing. Hence, we investigated the correspondence between LD50 results, in vitro assays, and a strong correlation with proteolytic activity levels was observed, showing, remarkably, that proteases are potential toxicity markers for Tityus serrulatus venom. The comparison of reversed-phase chromatographic profiles also has a potential application in venoms’ quality control, as there were fewer neurotoxins detected in the venom with high LD50 value. These results were confirmed by mass spectrometry analysis. Therefore, these methods could precede the LD50 assay to evaluate the venom excellence by discriminating—and discarding—poor-quality batches, and, consequently, with a positive impact on the number of animals used. Notably, proposed assays are fast and inexpensive, being technically and economically feasible in Tityus serrulatus venom quality control to produce effective antivenoms.

  12. A PC program for estimating organ dose and effective dose values in computed tomography

    International Nuclear Information System (INIS)

    Kalender, W.A.; Schmidt, B.; Schmidt, M.; Zankl, M.

    1999-01-01

    Dose values in CT are specified by the manufacturers for all CT systems and operating conditions in phantoms. It is not trivial, however, to derive dose values in patients from this information. Therefore, we have developed a PC-based program which calculates organ dose and effective dose values for arbitrary scan parameters and anatomical ranges. Values for primary radiation are derived from measurements or manufacturer specifications; values for scattered radiation are derived from Monte Carlo calculations tabulated for standard anthropomorphic phantoms. Based on these values, organ doses can be computed by the program for arbitrary scan protocols in conventional and in spiral CT. Effective dose values are also provided, both with ICRP 26 and ICRP 60 tissue-weighting coefficients. Results for several standard CT protocols are presented in tabular form in this paper. In addition, potential for dose reduction is demonstrated, for example, in spiral CT and in quantitative CT. Providing realistic patient dose estimates for arbitrary CT protocols is relevant both for the physician and the patient, and it is particularly useful for educational and training purposes. The program, called WinDose, is now in use at the Erlangen University hospitals (Germany) as an information tool for radiologists and patients. Further extensions are planned. (orig.)

  13. Protection of melanized Cryptococcus neoformans from lethal dose gamma irradiation involves changes in melanin's chemical structure and paramagnetism.

    Directory of Open Access Journals (Sweden)

    Abdelahad Khajo

    Full Text Available Certain fungi thrive in highly radioactive environments including the defunct Chernobyl nuclear reactor. Cryptococcus neoformans (C. neoformans, which uses L-3,4-dihydroxyphenylalanine (L-DOPA to produce melanin, was used here to investigate how gamma radiation under aqueous aerobic conditions affects the properties of melanin, with the aim of gaining insight into its radioprotective role. Exposure of melanized fungal cell in aqueous suspensions to doses of γ-radiation capable of killing 50 to 80% of the cells did not lead to a detectable loss of melanin integrity according to EPR spectra of melanin radicals. Moreover, upon UV-visible (Xe-lamp illumination of melanized cells, the increase in radical population was unchanged after γ-irradiation. Gamma-irradiation of frozen cell suspensions and storage of samples for several days at 77 K however, produced melanin modification noted by a reduced radical population and reduced photoresponse. More direct evidence for structural modification of melanin came from the detection of soluble products with absorbance maxima near 260 nm in supernatants collected after γ-irradiation of cells and cell-free melanin. These products, which include thiobarbituric acid (TBA-reactive aldehydes, were also generated by Fenton reagent treatment of cells and cell-free melanin. In an assay of melanin integrity based on the metal (Bi(+3 binding capacity of cells, no detectable loss in binding was detected after γ-irradiation. Our results show that melanin in C. neoformans cells is susceptible to some damage by hydroxyl radical formed in lethal radioactive aqueous environments and serves a protective role in melanized fungi that involves sacrificial breakdown.

  14. The monetary value of the averted dose for public exposure

    International Nuclear Information System (INIS)

    Katona, T.; Eged, K.; Kanyar, B.; Kis, Z.; Nenvei, A.

    2002-01-01

    In general, the concept of optimisation in radiation protection and safety appears as cost-minimisation in new procedures, methods in practices, and/or protective actions following unacceptable contamination. In the practical implementation of the concept, the cost of protective actions should be balanced with the benefits of exposure reduction. The monetary value of the averted dose can be assessed by the product of the cost of unit avoided collective dose (alpha-value) and the averted collective dose (ICRP 1991, 1993). According to the ICRP and others, the monetary value of the averted dose - in addition to the avoided health detriment - needs to take into account economical and social circumstances, ethical factors etc. (ICRP 1993, 2000; IBSS 1995; Oughton 2000). Most of the alpha-value assessments have been performed for workers (Hardeman et al. 1998; Lefaure 1998). Due to the different dose limitations and action levels for public exposures the monetary value of the averted dose may vary whether the averted dose refers to workers or to the public. Until now, only a few investigations have been performed to the public exposures. Eeckhoudt et al. (1999) proposed a method based on compensation dependency and on comparisons between the workers and the general public. The present paper includes the results obtained by the WTP method for the public. The questionnaire and analysis were developed by the CEPN (Centre d'Etude sur L'Evaluation de la Protection dans le Domaine Nucleaire, France) for specialists in the nuclear field (Leblanc et al. 1994). In 2000, questionnaire modifications were first introduced to adjust the Hungarian factors (Eged et al. 2001, 2002). The questionnaire was further modified in 2001 to take into account the Hungarian public factors

  15. Effects of melatonin in rats in the initial third stage of pregnancy exposed to sub-lethal doses of herbicides.

    Science.gov (United States)

    Almeida, Lécio Leone de; Teixeira, Álvaro Aguiar Coelho; Soares, Anísio Francisco; Cunha, Franklin Magliano da; Silva, Valdemiro Amaro da; Vieira Filho, Leucio Duarte; Wanderley-Teixeira, Valéria

    2017-04-01

    Exposure to the herbicides Paraquat (PQ) and Roundup ® may cause cell lesions due to an increase in oxidative stress levels in different biological systems, even in the reproductive system. Evaluate the possible changes in reproductive parameters and hepatic, as well as its prevention by simultaneous application of melatonin. Thirty-five female rats at the age of 3 months were divided into seven groups: three groups exposed to sub-lethal doses of the herbicides PQ (50mg/kg) and Roundup ® (500mg/kg) (n=5, G2, G3 and G4); three groups exposed to herbicides and simultaneous treatment with 10mg/kg of Melatonin (n=5, G5, G6 and G7) and control group (n=5, G1) from the first to the seventh day of pregnancy. On the seventh day of pregnancy, the rats were anesthetized and euthanized, followed by laparotomy to remove their reproductive tissues and liver. Body and ovary weights were taken and the number of implantation sites, corpora lutea, preimplantation losses, implantation rates were counted and histopathology of the implantation sites, morphometry of the surface and glandular epithelia of endometrium and hepatic oxidative stress were undertaken. The present study shows the decrease in body and ovary weight, decrease in the number of implantation sites, implantation rate, in the total number of corpora lutea and increase of preimplantation percentages were observed when compared to the G1: Fig. 1 and Table 1, (p>0.001 ANOVA/Tukey). The histopathological analysis of the implantation sites showed a disorder of the cytotrophoblast and cell degeneration within the blastocyst cavity in Fig. 4. Morphometry revealed a reduction in surface and glandular epithelia and in the diameter of the endometrial glands (Table 2; p>0.05 ANOVA/Tukey), whereas in liver, serum levels of thiobarbituric acid reactive substances (TBARS) were found to be significantly elevated (Fig. 2; p>0.001; p>0.05 ANOVA/Tukey), and serum level of reduced glutathione (GSH) was significantly lower (Fig. 3; p>0

  16. Patient dose reference values for explorations of radiodiagnostic

    International Nuclear Information System (INIS)

    Vano, E.; Gonzalez, L.; Moran, P.; Calzado, A.; Delgado, V.; Ruiz, M.J.

    1992-01-01

    Among the results of the research programs developed in the European Community dealing with radiological protection, dose estimation and quality control in radiodiagnostics, the preparation of a document on Quality criteria for radiodiagnostic images is worthy of note. This document proposes criteria for image quality and patient dose reference values for explorations of thorax, cranium, lumbar region, pelvis, urinary tract and breast. Said reference values, while indicative, are merely an average approximation, from which the radiodiagnostic services of each area may differ significantly, as can be deduced from a EC-coordinated project. With this in mind, and following a strategy applied in the EC to establish said reference values, in this report, provisional reference values, specific for Spain, are proposed for simple examinations (those analyzed by the group of EC experts, among others) and complex probes (intravenous urography, opaque enema and esophagogastroduodenal enema). (author)

  17. Chimeric anti-staphylococcal enterotoxin B antibodies and lovastatin act synergistically to provide in vivo protection against lethal doses of SEB.

    Directory of Open Access Journals (Sweden)

    Mulualem E Tilahun

    Full Text Available Staphylococcal enterotoxin B (SEB is one of a family of toxins secreted by Staphylococcus aureus that act as superantigens, activating a large fraction of the T-cell population and inducing production of high levels of inflammatory cytokines that can cause toxic shock syndrome (TSS and death. Extracellular engagement of the TCR of T-cells and class II MHC of antigen presenting cells by SEB triggers the activation of many intracellular signaling processes. We engineered chimeric antibodies to block the extracellular engagement of cellular receptors by SEB and used a statin to inhibit intracellular signaling. Chimeric human-mouse antibodies directed against different neutralizing epitopes of SEB synergistically inhibited its activation of human T-cells in vitro. In the in vivo model of lethal toxic shock syndrome (TSS in HLA-DR3 transgenic mice, two of these antibodies conferred significant partial protection when administered individually, but offered complete protection in a synergistic manner when given together. Similarly, in vivo, lovastatin alone conferred only partial protection from TSS similar to single anti-SEB antibodies. However, used in combination with one chimeric neutralizing anti-SEB antibody, lovastatin provided complete protection against lethal TSS in HLA-DR3 transgenic mice. These experiments demonstrate that in vivo protection against lethal doses of SEB can be achieved by a statin of proven clinical safety and chimeric human-mouse antibodies, agents now widely used and known to be of low immunogenicity in human hosts.

  18. A single dose of an inhibitor of cyclooxygenase 2, meloxicam, administered shortly after irradiation increases survival of lethally irradiated mice

    Czech Academy of Sciences Publication Activity Database

    Hofer, Michal; Pospíšil, Milan; Dušek, L.; Hoferová, Zuzana; Weiterová, Lenka

    2011-01-01

    Roč. 176, č. 2 (2011), s. 269-272 ISSN 0033-7587 R&D Projects: GA ČR(CZ) GA305/08/0158 Grant - others:GA ČR(CZ) GAP303/11/0128 Program:GA Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : cyclooxygenase-2 inhibition * lethal irradiation * survival Subject RIV: BO - Biophysics Impact factor: 2.684, year: 2011

  19. Acute Oral Toxicity of Tetrodotoxin in Mice: Determination of Lethal Dose 50 (LD50 and No Observed Adverse Effect Level (NOAEL

    Directory of Open Access Journals (Sweden)

    Paula Abal

    2017-02-01

    Full Text Available Tetrodotoxin (TTX is starting to appear in molluscs from the European waters and is a hazard to seafood consumers. This toxin blocks sodium channels resulting in neuromuscular paralysis and even death. As a part of the risk assessment process leading to a safe seafood level for TTX, oral toxicity data are required. In this study, a 4-level Up and Down Procedure was designed in order to determine for the first time the oral lethal dose 50 (LD50 and the No Observed Adverse Effect Level (NOAEL in mice by using an accurate well-characterized TTX standard.

  20. ECOS: sorption, dose, consumption and miscellaneous data values

    International Nuclear Information System (INIS)

    Kane, P.

    1984-10-01

    This report describes the nature of the data stored within the program ECOS, lists the values currently used and references the sources used. Also included are the element-specific equilibrium distribution coefficients (Ksub(D)) which are held in a data file external to ECOS. Nuclide-specific decay constants and dose factors are presented, as are certain plant- and animal-specific data not included in external files. Several miscellaneous items of data stored within ECOS are described. None of the data stored within ECOS are accessible to the user. (author)

  1. Clinical value of CARE dose 4D technique in decreasing CT scanning dose of adult chest

    International Nuclear Information System (INIS)

    Wu Aiqin; Zheng Wenlong; Xu Chongyong; Fang Bidong; Ge Wen

    2011-01-01

    Objective: To investigate the value of CARE Dose 4D technique in decreasing radiation dose and improving image quality of multi-slice spiral CT in adult chest scanning. Methods: 100 patients of chest CT scanning were equally divided into study group and control group randomly. CARE Dose 4D Technique was used in study group. Effective mAs value, volume CT dose index (CTDI vol ) and dose length product (DLP) were displayed automatically in machine while chest scanning; those values and actual mAs value of every image were recorded respectively. The image quality at apex of lung, lower edge of aorta arch, middle area of left atrium and base of lung on every image of 400 images was judged and classified as three level (excellent, good, poor) by two deputy chief physicians with double blind method, the image noise at corresponding parts was measured. Results: While setting 80 mAs for quality reference mAs, the effective mAs value in study group most decreased 44 mAs than control group with an average decrease of 9.60 (12.0%), CTDI vol with 4.75 mGy with an average decrease of 0.95 mCy (11.0%), DLP 99.50% in study group, with 98.0% in control group. But it was higher at apex of lung and base of lung, lower at middle area of left atrium, and similar at lower edge of aorta arch in study group than contrast group. The image noise were lower at apex of lung and base of lung in study group than control group (t =6.299 and 2.332, all P<0.05), higher at middle area of left atrium in study group than control group (t=3.078, P<0.05) and similar at lower edge of aorta arch in study group than control group (t=1.191, P>0.05). Conclusions: CARE Dose 4D technique provides a function regulated mAs real-time on line, it not only raises utilization rate of radiation and decreases radiation dose, but also promises and increases image quality in chest CT scanning, and has some clinical significance. (authors)

  2. Cyp1a1(-/-) male mice: protection against high-dose TCDD-induced lethality and wasting syndrome, and resistance to intrahepatocyte lipid accumulation and uroporphyria

    International Nuclear Information System (INIS)

    Uno, Shigeyuki; Dalton, Timothy P.; Sinclair, Peter R.; Gorman, Nadia; Wang, Bin; Smith, Andrew G.; Miller, Marian L.; Shertzer, Howard G.; Nebert, Daniel W.

    2004-01-01

    To study liver toxicity and uroporphyrin (URO) accumulation and urinary excretion, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent ligand for the aryl hydrocarbon receptor (AHR), is often used as the prototype. In this study, we asked the question how important is the role of CYP1A1 in causing TCDD toxicity. Using a single large intraperitoneal dose of TCDD (200 μg/kg) and following the response over an 8-week period, we found this dose: (a) was lethal in less than 4 weeks to Cyp1a1(+/+) males but not to Cyp1a1(-/-) males or to females of either genotype; (b) caused a wasting syndrome in Cyp1a1(+/+) but not Cyp1a1(-/-) mice; (c) resulted in thymic atrophy, regardless of gender or genotype; (d) decreased spleen size and caused leukocytopenia in males but not females of either genotype; (e) caused hepatocyte hypertrophy in Cyp1a1(+/+) more so than in Cyp1a1(-/-) mice; (f) increased intrahepatocyte lipids and total liver fat content in Cyp1a1(+/+) more than Cyp1a1(-/-) males and females; and (g) caused uroporphyria in Cyp1a1(+/+) males much more than Cyp1a1(+/+) females, or in Cyp1a1(-/-) mice. Contrary to Cyp1a2(-/-) knockout mice that exhibited 15 times less accumulation of TCDD in liver than Cyp1a1/1a2(+/+) wild-type mice, Cyp1a1(-/-) mice did not show this altered TCDD distribution - indicating that CYP1A2 but not CYP1A1 is the major hepatic TCDD-binding 'sink'. Our data demonstrate that CYP1A1 contributes to high-dose TCDD-induced toxicity, uroporphyria, and lethality

  3. New values of some physical interaction coefficients for dose measurements

    International Nuclear Information System (INIS)

    Eisenlohr, H.H.; Zsdanszky, K.

    1986-01-01

    At its 8th meeting in 1985 Section I of the ''Comite Consultatif pour les Etalons de Mesure des Rayonnements lonisants'' (CCEMRI) to the ''Comite International des Poids et Mesures'' (CIPM) has put forward a recommendation on new values of some physical constants to be used for exposure and absorbed dose determinations (see Annex I). Implementation of this recommendation has some impact on the measurement of exposure, air kerma and absorbed dose, and may result in changes in calibration factors of dosimeters. This subject will be discussed in detail at the IAEA Workshop on Calibration Procedures in Dosimetry, to be held in Quito in October 1986. The following information may assist SSDLs in preparing themselves for the expected changes of calibration factors. The recommendation has been caused by new numerical values of some physical constants which have become available recently. The two most important changes concern: a) S m,a , the ratio of the mean restricted collision mass stopping powers of the chamber material to that of air for electrons crossing the cavity, and b) W air /e, the mean energy required to produce an ion pair in air per electron charge, for electrons emitted by radioactive sources or produced by photon absorption

  4. Non-lethal approach identifies variability of δ15N values in the fin rays of Atlantic Goliath Grouper, Epinephelus itajara

    Directory of Open Access Journals (Sweden)

    Orian E. Tzadik

    2015-06-01

    Full Text Available The Atlantic Goliath Grouper, Epinephelus itajara, is critically endangered throughout its range but has begun to show initial signs of recovery in Florida state waters. As the population continues to rebound, researchers face a pressing need to fill the knowledge gaps about this iconic species. Here, we examined the δ15N isotopic records in fin rays collected from Atlantic Goliath Grouper, and related changes of isotopic ratios over time to life history characteristics. Fin-ray analysis was used as a non-lethal technique to sample individuals from two locations at similar latitudes from the west and east coasts of Florida, USA. δ15N data were acquired by mechanically separating the annuli of each fin ray and then analyzing the material in an Irradiance Elemental Analyzer Mass Spectrometer. The δ15N values were consistent among individuals within populations from each coast of Florida, and mirrored the expected changes over the lives of the fish. Overall, differences were found between δ15N values at juvenile life history phases versus adult phases, but the patterns associated with these differences were unique to each coastal group. We demonstrated, for the first time, that δ15N values from fin rays can be used to assess the life histories of Atlantic Goliath Grouper. The non-lethal strategies outlined here can be used to acquire information essential to the management of species of concern, such as those that are threatened or endangered.

  5. Lethal doses of ozone for control of all stages of internal and external feeders in stored products

    DEFF Research Database (Denmark)

    Hansen, Lise S.; Hansen, Peer; Jensen, Karl-Martin V.

    2012-01-01

    Gaseous ozone (O3) has potential for control of insects in stored grain. Previous studies have focused on freely exposed insects. Immatures of internal pests, (e.g. Sitophilus spp. and most stages of Rhyzopertha dominica F.) are protected within kernels and probably require higher doses and....../or longer treatment times for full control. A laboratory study determined the doses of ozone necessary for full control of freely exposed and internal stages of eleven stored product pest species. Test insects were three species of Sitophilus, R. dominica, Tribolium confusum Jacquelin du Val, T. castaneum...

  6. Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation; Etude clinique et symptomatologique chez le porc soumis a une irradiation gamma totale a dose letale

    Energy Technology Data Exchange (ETDEWEB)

    Vaiman, M; Guenet, J -L; Maas, J; Nizza, P

    1966-05-01

    Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of {gamma} radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [French] Les auteurs rapportent les resultats d'une etude clinique et hematologique chez des porcs de race corse irradies in toto a dose sensiblement letale. Le but de cette etude etait de connaitre l'evolution du syndrome aigu d'irradiation chez le porc et de permettre ainsi le developpement d'experimentations ulterieures, en particulier dans le domaine therapeutique. La dose delivree etait de 285 rad (en dose absorbee au niveau du plan median vertical anteroposterieur. L'etude a porte essentiellement: 1. Sur les modifications cyclo-hematologiques du sang circulant immediatement apres l'irradiation, pour les differentes lignees cellulaires; l'evolution de ces modifications a ete notee jusqu'a la mort; 2. Sur les modifications de la cytologie medullaire apres irradiation (evolution du myelogramme et essai d'evaluation de la cellularite de la moelle osseuse);: 3. Sur les signes cliniques, d'ailleurs tres discrets, observes chez les porcs apres irradiation. (auteurs)

  7. Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation; Etude clinique et symptomatologique chez le porc soumis a une irradiation gamma totale a dose letale

    Energy Technology Data Exchange (ETDEWEB)

    Vaiman, M.; Guenet, J.-L.; Maas, J.; Nizza, P

    1966-05-01

    Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of {gamma} radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [French] Les auteurs rapportent les resultats d'une etude clinique et hematologique chez des porcs de race corse irradies in toto a dose sensiblement letale. Le but de cette etude etait de connaitre l'evolution du syndrome aigu d'irradiation chez le porc et de permettre ainsi le developpement d'experimentations ulterieures, en particulier dans le domaine therapeutique. La dose delivree etait de 285 rad (en dose absorbee au niveau du plan median vertical anteroposterieur. L'etude a porte essentiellement: 1. Sur les modifications cyclo-hematologiques du sang circulant immediatement apres l'irradiation, pour les differentes lignees cellulaires; l'evolution de ces modifications a ete notee jusqu'a la mort; 2. Sur les modifications de la cytologie medullaire apres irradiation (evolution du myelogramme et essai d'evaluation de la cellularite de la moelle osseuse);: 3. Sur les signes cliniques, d'ailleurs tres discrets, observes chez les porcs apres irradiation. (auteurs)

  8. Comparison between dose values specified at the ICRU reference point and the mean dose to the planning target volume

    International Nuclear Information System (INIS)

    Kukoowicz, Pawel F.; Mijnheer, Bernard J.

    1997-01-01

    Background and purpose: To compare dose values specified at the reference point, as recommended by the International Commission on Radiation Units and Measurements, ICRU, and the mean dose to the planning target volume, PTV. Material and methods: CT-based dose calculations were performed with a 3-D treatment planning system for 6 series of patients treated for bladder, brain, breast, lung, oropharynx and parotid gland tumour. All patients were arbitrarily chosen from a set of previously treated patients irradiated with a two- or three-field technique using customised blocks. Appropriate wedge angles and beam weights were chosen to make the dose distribution as homogeneous as possible. Results: The dose at the ICRU reference point was generally higher than the mean dose to the PTV. The difference between the ICRU reference dose and the mean dose to the PTV for an individual patient was less than 3% in 88% of cases and less than 2% in 72% of the cases. The differences were larger in those patients where the dose distribution is significantly influenced by the presence of lungs or air gaps. For each series of patients the mean difference between the ICRU reference dose and the mean dose to the PTV was calculated. The difference between these two values never exceeded 2%. Because not all planning systems are able to calculate the mean dose to the PTV, the concept of the mean central dose, the mean of the dose values at the centre of the PTV in each CT slice, has been introduced. The mean central dose was also calculated for the same patients and was closer to the mean dose to the PTV than the ICRU reference dose. Conclusion: The mean dose to the PTV is well estimated by either the ICRU reference dose or the mean central dose for a variety of treatment techniques for common types of cancer

  9. Lethal Epistaxis.

    Science.gov (United States)

    Byard, Roger W

    2016-09-01

    Epistaxis or nosebleed refers to bleeding from the nostrils, nasal cavity, or nasopharynx. Occasional cases may present with torrential lethal hemorrhage. Three cases are reported to demonstrate particular features: Case 1: A 51-year-old woman with lethal epistaxis with no obvious bleeding source; Case 2: A 77-year-old man with treated nasopharyngeal carcinoma who died from epistaxis arising from a markedly neovascularized tumor bed; Case 3: A 2-year-old boy with hemophilia B who died from epistaxis with airway obstruction in addition to gastrointestinal bleeding. Epistaxis may be associated with trauma, tumors, vascular malformations, bleeding diatheses, infections, pregnancy, endometriosis, and a variety of different drugs. Careful dissection of the nasal cavity is required to locate the site of hemorrhage and to identify any predisposing conditions. This may be guided by postmortem computerized tomographic angiography (PCTA). Despite careful dissection, however, a source of bleeding may never be identified. © 2016 American Academy of Forensic Sciences.

  10. A mathematical approach to optimal selection of dose values in the additive dose method of ERP dosimetry

    International Nuclear Information System (INIS)

    Hayes, R.B.; Haskell, E.H.; Kenner, G.H.

    1996-01-01

    Additive dose methods commonly used in electron paramagnetic resonance (EPR) dosimetry are time consuming and labor intensive. We have developed a mathematical approach for determining optimal spacing of applied doses and the number of spectra which should be taken at each dose level. Expected uncertainitites in the data points are assumed to be normally distributed with a fixed standard deviation and linearity of dose response is also assumed. The optimum spacing and number of points necessary for the minimal error can be estimated, as can the likely error in the resulting estimate. When low doses are being estimated for tooth enamel samples the optimal spacing is shown to be a concentration of points near the zero dose value with fewer spectra taken at a single high dose value within the range of known linearity. Optimization of the analytical process results in increased accuracy and sample throughput

  11. Comparative lethality kinetic curves and predictive models of F-value for Listeria monocytogenes using different sanitizers

    Science.gov (United States)

    Beltrame, Cezar A; Kubiak, Gabriela B; Rottava, Ieda; Toniazzo, Geciane; Cansian, Rogério L; Lerin, Lindomar A; de Oliveira, Débora; Treichel, Helen

    2013-01-01

    The objective of this work was to evaluate the kinetic of inactivation of Listeria monocytogenes using peracetic acid, chlorhexidine, and organic acids as active agent, determining the respective D-, Z-, and F-values. From our knowledge, these important results from an industrial view point are not available in the current literature, mainly for organic acids, pointing out the main contribution of the present work. Lower D-values were obtained for peracetic acid and chlorhexidine, compared with the organic acids. For the reduction of 6 log10 of L. monocytogenes using peracetic acid, at 0.2, 0.1, and 0.05% are necessary 7.08, 31.08, and 130.44 min of contact, respectively. The mathematical models of F-values showed that at concentrations lower than 0.15% one can verify an exponential increase in F-values, for both de chlorhexidine and peracetic acid. The organic acids presented a linear behavior, showing slight variation in F-values, is even more effective in under dosage. The results obtained are of fundamental importance in terms of industrial strategy for sanitization procedure, permitting to choose the best relation product concentration/exposure time, aiming at reducing costs without compromising the disinfectant efficiency. PMID:24804011

  12. Application of maximum values for radiation exposure and principles for the calculation of radiation doses

    International Nuclear Information System (INIS)

    2007-08-01

    The guide presents the definitions of equivalent dose and effective dose, the principles for calculating these doses, and instructions for applying their maximum values. The limits (Annual Limit on Intake and Derived Air Concentration) derived from dose limits are also presented for the purpose of monitoring exposure to internal radiation. The calculation of radiation doses caused to a patient from medical research and treatment involving exposure to ionizing radiation is beyond the scope of this ST Guide

  13. Effect of Linezolid on the 50% Lethal Dose and 50% Protective Dose in Treatment of Infections by Gram-Negative Pathogens in Naive and Immunosuppressed Mice and on the Efficacy of Ciprofloxacin in an Acute Murine Model of Septicemia

    Science.gov (United States)

    Marra, Andrea; Lamb, Lucinda; Medina, Ivette; George, David; Gibson, Glenn; Hardink, Joel; Rugg, Jady; Van Deusen, Jeffrey

    2012-01-01

    Murine models of infection were used to study the effect of linezolid on the virulence of Gram-negative bacteria and to assess potential pharmacodynamic interactions with ciprofloxacin in the treatment of these infections, prompted by observations from a recent clinical trial. Naive and immunosuppressed mice were challenged with Klebsiella pneumoniae 53A1109, K. pneumoniae GC6658, and Pseudomonas aeruginosa UC12120 in acute sepsis and pulmonary infection models, using different serial dilutions of these pathogens (groups of 8 animals each). Linezolid (100 mg/kg/dose) was administered orally at 0.5 and 4.0 h postchallenge in the sepsis model and at 4 h postchallenge followed by 2 days of twice-daily treatment in the pulmonary model. Further, ciprofloxacin alone and in combination with oral linezolid was investigated in the sepsis model. Survival was assessed for 4 and 10 days postchallenge in the systemic and respiratory models, respectively. The data were fitted to a nonlinear regression analysis to determine 50% lethal doses (LD50s) and 50% protective doses (PD50s). A clinically relevant, high-dose regimen of linezolid had no significant effect on LD50 in these models. This lack of effect was independent of immune status. A combination of oral ciprofloxacin with linezolid yielded lower PD50s than oral ciprofloxacin alone (ciprofloxacin in combination, 8.4 to 32.7 mg/kg; oral ciprofloxacin, 39.4 to 88.3 mg/kg). Linezolid did not improve the efficacy of subcutaneous ciprofloxacin (ciprofloxacin in combination, 2.0 to 2.4 mg/kg; subcutaneous ciprofloxacin, 2.0 to 2.8 mg/kg). In conclusion, linezolid does not seem to potentiate infections caused by Gram-negative pathogens or to interact antagonistically with ciprofloxacin. PMID:22710118

  14. Median lethal dose determination for percutaneous exposure to soman and VX in guinea pigs and the effectiveness of decontamination with M291 SDK or SANDIA foam.

    Science.gov (United States)

    Clarkson, Edward D; Schulz, Susan M; Railer, Roy F; Smith, Kelly H

    2012-08-03

    Soman (GD) and VX are chemical warfare agents that can be absorbed through the skin. We determined the median lethal dose (MLD) for the cutaneous application of GD and VX in anesthetized haired guinea pigs and then tested the ability of a currently fielded decontamination kit, the M291 Skin Decontamination Kit (SDK), and decontaminating foam made by SANDIA Labs to decontaminate areas that have been exposed to cutaneous applications of GD and VX. The fur of guinea pigs was clipped on the left flank 24h prior to exposure. Animals were anesthetized and 5 min later neat GD or neat VX was applied. The MLD for percutaneous exposure to GD was 11.6 mg/kg, and to VX it was 0.10mg/kg. To test the ability of the M291 SDK, either GD or VX was applied and removed 1 min later with the pads of the M291 SDK clasped in a pair of forceps and wiped across the flank of the animal. The MLDs for GD and VX removed with the M291 SDK pads were 76.9 mg/kg and 0.87 mg/kg, respectively. When neat GD or neat VX was applied and removed 1 min later in the same manner with gauze soaked in SANDIA foam (MDF-100), the MLDs were 412 mg/kg and 10.4 mg/kg respectively. These data demonstrate that GD and VX are significantly less potent when applied cutaneously than previously reported for subcutaneous injections and indicate that improvement is needed on the limited protective ratio provided by the M291 SDK. Published by Elsevier Ireland Ltd.

  15. Comparison of the Concentrations of Lidocaine in Different Body Fluids/Tissues after Subarachnoid Space and Intravenous Administration of a Lethal Dose of Lidocaine

    Directory of Open Access Journals (Sweden)

    Nan Zhang

    2015-01-01

    Full Text Available The objective of the study was to compare the concentration of lidocaine in different body fluids/tissues after subarachnoid space and intravenous administrations of a lethal dose of lidocaine. Totally 18 dogs were used in the experiment. Six dogs were given subarachnoid anesthesia, another were given an intravenous injection of a dose of 75 mg/kg weight of lidocaine hydrochloride in 5 min and the last 6 dogs were used as the blank control dogs and given a subarachnoid space injection or a femoral artery injection of the same volume of sodium chloride. As soon as its vital signs disappeared, each dog was dissected and the specimen, such as brain, cerebrospinal fluid (CSF in lateral ventricle, CSF in subarachnoid space, spinal cord (cervical spinal cord, thoracic spinal cord, lumbar spinal cord, and waist spinal cord, heart, lung, liver, spleen, kidney, bile, urine, heart blood, peripheral blood, muscle in injection location, and muscle in no injection location, were collected for analysis of lidocaine immediately. Analysis was performed with gas chromatography-mass spectrometry (GC-MS. From the maximum to the minimum, the order of lidocaine concentration detected in the subarachnoid space-administered dogs was as follows: CSF in subarachnoid space, waist spinal cord, thoracic spinal cord, CSF in lateral ventricle, lumbar spinal cord, cervical spinal cord, lung, kidney, muscle in injection location, heart, brain, spleen, heart blood, liver, peripheral blood, bile, muscle in no injection location, and urine. The order of lidocaine concentration detected in the intravenously administered dogs was as followed: Kidney, heart, lung, spleen, brain, liver, peripheral blood, bile, heart blood, cervical spinal cord, thoracic spinal cord, muscle in injection location, lumbar spinal cord, muscle in no injection location, CSF in subarachnoid space, urine, and CSF in lateral ventricle. The maximum concentration of lidocaine was detected in the subarachnoid

  16. Novel Insect-Specific Eilat Virus-Based Chimeric Vaccine Candidates Provide Durable, Mono- and Multivalent, Single-Dose Protection against Lethal Alphavirus Challenge.

    Science.gov (United States)

    Erasmus, Jesse H; Seymour, Robert L; Kaelber, Jason T; Kim, Dal Y; Leal, Grace; Sherman, Michael B; Frolov, Ilya; Chiu, Wah; Weaver, Scott C; Nasar, Farooq

    2018-02-15

    Most alphaviruses are mosquito borne and exhibit a broad host range, infecting many different vertebrates, including birds, rodents, equids, humans, and nonhuman primates. Recently, a host-restricted, mosquito-borne alphavirus, Eilat virus (EILV), was described with an inability to infect vertebrate cells based on defective attachment and/or entry, as well as a lack of genomic RNA replication. We investigated the utilization of EILV recombinant technology as a vaccine platform against eastern (EEEV) and Venezuelan equine encephalitis viruses (VEEV), two important pathogens of humans and domesticated animals. EILV chimeras containing structural proteins of EEEV or VEEV were engineered and successfully rescued in Aedes albopictus cells. Cryo-electron microscopy reconstructions at 8 and 11 Å of EILV/VEEV and EILV/EEEV, respectively, showed virion and glycoprotein spike structures similar to those of VEEV-TC83 and other alphaviruses. The chimeras were unable to replicate in vertebrate cell lines or in brains of newborn mice when injected intracranially. Histopathologic examinations of the brain tissues showed no evidence of pathological lesions and were indistinguishable from those of mock-infected animals. A single-dose immunization of either monovalent or multivalent EILV chimera(s) generated neutralizing antibody responses and protected animals against lethal challenge 70 days later. Lastly, a single dose of monovalent EILV chimeras generated protective responses as early as day 1 postvaccination and partial or complete protection by day 6. These data demonstrate the safety, immunogenicity, and efficacy of novel insect-specific EILV-based chimeras as potential EEEV and VEEV vaccines. IMPORTANCE Mostly in the last decade, insect-specific viruses have been discovered in several arbovirus families. However, most of these viruses are not well studied and largely have been ignored. We explored the use of the mosquito-specific alphavirus EILV as an alphavirus vaccine

  17. OCCUPATIONAL DOSE DURING ADULT INTERVENTIONAL CARDIOLOGY: FIRST VALUES WITH PERSONAL ACTIVE DOSIMETERS IN CHILE.

    Science.gov (United States)

    Ubeda, Carlos; Morales, Claudio; Gutiérrez, Diego; Oliveira, Marcus; Manterola, Carlos

    2018-05-11

    The objective of this article is to present initial occupational dose values using digital active personal dosimeters for medical staff during adult interventional cardiology procedures in a public hospital in Chile. Personal dose equivalent Hp(10) over the lead apron of physician, nurse and radiographer were measured during 59 procedures. Mean values of occupational dose Hp(10) per procedure were 47.6, 6.2 and 4.3 μSv for physician, nurse and radiographer, respectively. If no protective tools are used, physician dose can exceed the new eye lens dose limit.

  18. Guideline values for skin decontamination measures based on nuclidspecific dose equivalent rate factors

    International Nuclear Information System (INIS)

    Pfob, H.; Heinemann, G.

    1992-01-01

    Corresponding dose equivalent rate factors for various radionuclides are now available for determining the skin dose caused by skin contamination. These dose equivalent rate factors take into account all contributions from the types of radiation emitted. Any limits for skin decontamination measures are nowhere contained or determined yet. However, radiological protection does in practice require at least guideline values in order to prevent unsuitable or detrimental measures that can be noticed quite often. New calculations of dose equivalent rate factors for the skin now make the recommendation of guideline values possible. (author)

  19. Application of maximum values for radiation exposure and principles for the calculation of radiation dose

    International Nuclear Information System (INIS)

    2000-01-01

    The guide sets out the mathematical definitions and principles involved in the calculation of the equivalent dose and the effective dose, and the instructions concerning the application of the maximum values of these quantities. further, for monitoring the dose caused by internal radiation, the guide defines the limits derived from annual dose limits (the Annual Limit on Intake and the Derived Air Concentration). Finally, the guide defines the operational quantities to be used in estimating the equivalent dose and the effective dose, and also sets out the definitions of some other quantities and concepts to be used in monitoring radiation exposure. The guide does not include the calculation of patient doses carried out for the purposes of quality assurance

  20. Application of maximum values for radiation exposure and principles for the calculation of radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The guide sets out the mathematical definitions and principles involved in the calculation of the equivalent dose and the effective dose, and the instructions concerning the application of the maximum values of these quantities. further, for monitoring the dose caused by internal radiation, the guide defines the limits derived from annual dose limits (the Annual Limit on Intake and the Derived Air Concentration). Finally, the guide defines the operational quantities to be used in estimating the equivalent dose and the effective dose, and also sets out the definitions of some other quantities and concepts to be used in monitoring radiation exposure. The guide does not include the calculation of patient doses carried out for the purposes of quality assurance.

  1. Values of dose and individual of a individual thermoluminescent dosimeter submitted to x and gamma radiations

    International Nuclear Information System (INIS)

    Moraes, Cassiana Viccari de; Pela, Carlos Alberto

    2001-01-01

    The individual monitoring provides information for the control of exposures, and estimates the dose received by individuals. This is an essential tool in personal dosimetry. It's based on a radiation protection concept, allowing an individual exposure control, besides guaranteeing that the dose restrictions will not be exceeded. Usually, the dose monitoring is performed by using an individual dosemeter placed on a representative position of the most exposed point on the thoracic surface. The dosemeter, which is analyzed in the present work, is made of three CaSO 4 -Dy thermoluminescent detectors, plastic filters, copper and copper-lead, mounted in an acrylic support. The dose received by on each detector, which forms the dosemeter, is related according to their energetic curve dependence. The dose amount is calculated from these curves by using an algorithm, and it was taken in to consideration the detector calibration and thermoluminescent responses, due to the x and g radiation exposure. That algorithm has the capacity to determine the energies that were irradiated the detector. Therefore, to aid the service in the moment of evaluate the dose received by the individual and where it is coming from. The algorithm has provided individual dose value H x , defined as operational quantity for photons adopted in the Brazilian Metric System. The algorithm can determine two dose values and such values have been analyzed according to the kind of irradiated energy on the dosimeter and it has shown that both values are within established limits by Instituto de Radioprotecao e Dosimetria (IRD). (author)

  2. Proposal of dose constraint values to the patient in diagnostic radiology

    International Nuclear Information System (INIS)

    Arranz, L.; Sastre, J.M.; Ferrer, N.; Andres, J.C. De; Guibelalde, E.; Tobarra, B.; Madrid, G.

    1996-01-01

    A dose constraint is the value of an individual dose not to be exceeded in the individual dose distribution considered in an optimization process. The objective of a dose constraints is to set a ceiling to the doses to individual from a source, practice or task which are considered acceptable in the optimization process at the design stage. Implicitly, as C. Zuur states, dose constraints are below the relevant dose limit and usually should be established as local or national levels. Exposures for medical purposes are not subject to dose limits and hence dose constraints were recommended by the ICRP just for occupational and public exposures. However, as an effective tool for optimization for medical exposures, ICRP-60 in paragraph 180 recognizes the value of applying this concept to patient diagnostic radiology with some peculiarities: 'Considerations should be given to the use of dose constraints, or investigation levels, selected by the appropriate professional or regulatory agency, for application in some common diagnostic procedures. They should be applied with flexibility to allow higher cases where indicated by sound clinical judgement.' This paper analyzes retrospectively the dose levels imparted to patient in some common examinations (chest, lumbar spine and mammography) at different optimization stages of different facilities to propose some local constraints for diagnostic examinations. Dose values have been obtained under routine working conditions. Centres included in the survey have been chosen all over Spain, classifying them with particular attention to the following aspects: -Organizational aspects of the diagnostic radiology service, i.e., operational, technical and clinical criteria, as well as quality requirements. - Evaluation and revision of routine medical protocols. -Quality control of the radiological equipment. - Quality criteria for the surveillance of the weekly procedures, with requirements of proper training of die technical staff

  3. Dose estimation in CT exams of the abdomen based on values of DLP

    International Nuclear Information System (INIS)

    Kikuti, C.F.; Medeiros, R.B.; Salvadori, P.S.; Costa, D.M.C; D'lppolito, G.

    2013-01-01

    One of the challenges of multidetector computerized tomography is to minimize the risk of ionizing radiation using optimized protocols since higher doses are necessary to obtain high image quality. It was also noted that, due to the geometry in image acquisition using MDCT becomes necessary to estimate dose values consistent with the hypothesis clinically and with the specificities of the tomographic equipment. The aim of this study was to estimate the doses in abdomen exams from the data recorded on the MDCT console and dimensions obtained from DICOM images of patients undergoing different clinical protocols. Were collected, from the image DICOM of 101 exams, values of the dose length product (DLP) provided by Philips Health Care - Brilliance 64 equipment console, in order to relate them with the dose values obtained by means of thermoluminescent dosimeters ( TLD ) of CasSo 4 :Mn placed on the surface of a cylindrical simulator abdomen acrylic manufactured under the technical - operational conditions for a typical abdomen exam. From the data obtained, it was possible to find a factor of 1.16 ( 5 % ) indicating that the DLP values Brilliance 64 console underestimate the doses and this should be used with correction factor to estimate the total dose of the patient. (author)

  4. Value of public health and safety actions and radiation dose avoided

    International Nuclear Information System (INIS)

    Baum, J.W.

    1994-05-01

    The values judged best to reflect the willingness of society to pay for the avoidance or reduction of risk were deduced from studies of costs of health care, transportation safety, consumer product safety, government agency actions, wage-risk compensation, consumer behavior (market) studies, and willingness-to-pay surveys. The results ranged from $1,400,000 to $2,700,000 per life saved. Applying the mean of these values ($2,100,000) and the latest risk per unit dose coefficients used by the ICRP (1991), which take into account risks to the general public, including genetic effects and nonfatal cancers, yields a value of dose avoided of $750 to $1,500 per person-cSv for public exposures. The lower value applies if adjustments are made for years of life lost per fatality. A nominal value of $1,000 per person-cSv seems appropriate in light of the many uncertainties involved in deducing these values. These values are consistent with values recommended by several European countries for individual doses in the region of 1 mSv/y (100 mrem/y). Below this dose rate, most countries have values a factor of 7 to 10 lower, based on the assumption that society is less concerned with fatality risks below about 10 -4 /y

  5. Value of public health and safety actions and radiation dose avoided

    Energy Technology Data Exchange (ETDEWEB)

    Baum, J.W. [Brookhaven National Lab., Upton, NY (United States)

    1994-05-01

    The values judged best to reflect the willingness of society to pay for the avoidance or reduction of risk were deduced from studies of costs of health care, transportation safety, consumer product safety, government agency actions, wage-risk compensation, consumer behavior (market) studies, and willingness-to-pay surveys. The results ranged from $1,400,000 to $2,700,000 per life saved. Applying the mean of these values ($2,100,000) and the latest risk per unit dose coefficients used by the ICRP (1991), which take into account risks to the general public, including genetic effects and nonfatal cancers, yields a value of dose avoided of $750 to $1,500 per person-cSv for public exposures. The lower value applies if adjustments are made for years of life lost per fatality. A nominal value of $1,000 per person-cSv seems appropriate in light of the many uncertainties involved in deducing these values. These values are consistent with values recommended by several European countries for individual doses in the region of 1 mSv/y (100 mrem/y). Below this dose rate, most countries have values a factor of 7 to 10 lower, based on the assumption that society is less concerned with fatality risks below about 10{sup {minus}4}/y.

  6. Feasibility of applying gamma irradiation as disinfestation technique on date fruits in respect to nutritional value that is affected by disinfesting gamma ray doses

    International Nuclear Information System (INIS)

    Ahmed, El-Sayed S.

    1976-01-01

    Infested and non-infested dry date fruits (Phonex dactylifera), Abrimi variety (9.2% moisture), with Ephestia cautella Walker were irradiated for 0, 15, 20 and 40 Krad gamma ray doses emitted from Co-60 source with 1.36 x 10-rad/h. as a dose rate. Irradiated fruits were stored at room temperature, at 20-25 0 C and 85-95% R.H., in packages to avoid reinfestation. A dose of 20 Krad is 100 percent effective in preventing the emergency of eggs, larva, and pupae in fruits as reflected by zero per cent emergency count for live adults. Also, this dose was found to be lethal for adult stage of the insect. On the other hand, 2 Krad dose does not produce significant changes in the nutritional qualities of fruits, as measured by chemical analytical means for carbohydrates, protein and amino acids, directly after irradiation as well as at 2, 4 and 6 months storage. The triangular tests show that irradiation treatments even with 4 Krad exerted no determinal effect upon the sensory qualities of stored irradiated date fruits. These results point out the feasibility of applying gamma irradiation, 20 Krad, as disinfestation technique against Ephestia cautella Walker in dry date fruits without exerting any effect on the nutritional value

  7. The Alpha value decrease when the annual individual effective dose decreases?

    International Nuclear Information System (INIS)

    Sordi, Gian M.; Marchiusi, Thiago; Sousa, Jefferson de J.

    2008-01-01

    A recent IAEA publication tells that a few entities took different alpha values for maxima individual doses. Beyond to disregard the international agencies, that recommend only one alpha value for each country, the alpha values decreases when the individual doses decreases and the practice happens exactly the conversely as we will show in this paper. We will prove that the alpha value increase when the maximum individual doses decreases in a four different manner. The first one we call the theoretical conception and it is linked to the emergent of the ALARA policy and to the purpose that led to the 3/10 of the annual limits, for to decrease the individual doses as a first resort and a 1/10 as a last resort. The second prove will be based in a small mine example used in the ICRP publication number 55 concerning to the optimization and the quantitative decision-aiding techniques in radiological protection where we will determine the alpha value ranges in which each radiological protection options becomes the analytical solution. The third prove will be based in the determination of the optimized thickness example of a plane shielding for a radiation source exposed in the ICRP publication number 37. We will use, also, the numerical example provided there. Eventually, as four prove we will show that the alpha value dos not only increases with the maximum individual dose decrease, but also, with the shielding geometry. (author)

  8. Absorbed dose to the urinary bladder wall for different radiopharmaceuticals using dynamic S-values

    International Nuclear Information System (INIS)

    Andersson, M.; Minarik, D.; Mattsson, S.; Leide-Svegborn; Johansson, L.

    2015-01-01

    Full text of publication follows. Aim and background: the urinary bladder wall is a radiosensitive organ that can receive a high absorbed dose from radiopharmaceuticals used in diagnostic nuclear medicine. Current dynamic models estimate the photon and electron absorbed dose at the inner surface of the bladder wall. The aim of this work has been to create a more realistic estimation of the mean absorbed dose to the urinary bladder wall from different radiopharmaceuticals. This calculation also uses dynamic specific absorption fractions (SAF) that changes with bladder volume and are gender specific. Materials and Methods: the volume of the urinary bladder content was calculated using a spherical approximation with a urinary inflow of 1.0 ml/min and 0.5 ml/min during day and night time, respectively. The activity in the bladder content was described using a bi-exponential extraction from the body. The absorbed dose to the bladder wall was estimated using linear interpolation of SAF values from different bladder volumes, ranging from 10 ml to 800 ml. Administration of the activity was assumed to start at 09:00 with an initial voiding after 40 minutes and a voiding interval of 3.5 hours during the day. A six hour night gap, starting at midnight, with a voiding right before and after the night period, was used. Calculations were made, with the same assumptions, for an earlier dynamic bladder model and with a static SAF value from the ICRP/ICRU adult reference computational phantoms for a bladder containing 200 ml. Values for the absorbed dose per unit administered activity for 19 commonly used radiopharmaceuticals were calculated, e.g. 18 F-FDG, 99m Tc-pertechnetate, 99m Tc-MAG3 and 123 I-NaI. Results and conclusion: the results of the estimates of the absorbed doses to the inner bladder wall were a factor of ten higher than the estimates mean absorbed doses. The mean absorbed doses to the bladder wall were slightly higher for females than males, due to a smaller female

  9. The Effect Of Inoculation Dose Of trypanosoma Evansi On Blood Value In Animal Hosts f Mice

    International Nuclear Information System (INIS)

    Arifin, M.

    2002-01-01

    An experiment was carried out to obtain the information and its relation between a number of parasites and pathogenity in mice. The pathogenity of T. evansi was depend on the exchange of blood value of infected mice. The parasites was irradiated by gamma rays 6 O C o with the dose of and 300 Gy. The dose of inoculation were 1 x 10 5 , 5 x 10 5 and 1 x 10 6 parasites per mice. The results obtained showed that a number of parasites were inoculated caused the drop of blood value of mice. The number of parasites and irradiation were also significant effect to the blood value (P<0.01)

  10. Staff lens doses in interventional urology. A comparison with interventional radiology, cardiology and vascular surgery values

    International Nuclear Information System (INIS)

    Vano, E; Fernandez, J M; Sanchez, R M; Resel, L E; Moreno, J

    2016-01-01

    The purpose of this work is to evaluate radiation doses to the lens of urologists during interventional procedures and to compare them with values measured during interventional radiology, cardiology and vascular surgery. The measurements were carried out in a surgical theatre using a mobile C-arm system and electronic occupational dosimeters (worn over the lead apron). Patient and staff dose measurements were collected in a sample of 34 urology interventions (nephrolithotomies). The same dosimetry system was used in other medical specialties for comparison purposes. Median and 3rd quartile values for urology procedures were: patient doses 30 and 40 Gy cm 2 ; personal dose equivalent Hp(10) over the apron (μSv/procedure): 393 and 848 (for urologists); 21 and 39 (for nurses). Median values of over apron dose per procedure for urologists resulted 18.7 times higher than those measured for radiologists and cardiologists working with proper protection (using ceiling suspended screens) in catheterisation laboratories, and 4.2 times higher than the values measured for vascular surgeons at the same hospital. Comparison with passive dosimeters worn near the eyes suggests that dosimeters worn over the apron could be a reasonable conservative estimate for ocular doses for interventional urology. Authors recommend that at least the main surgeon uses protective eyewear during interventional urology procedures. (paper)

  11. Site-specific parameter values for the Nuclear Regulatory Commission's food pathway dose model

    International Nuclear Information System (INIS)

    Hamby, D.M.

    1992-01-01

    Routine operations at the Savannah River Site (SRS) in Western South Carolina result in radionuclide releases to the atmosphere and to the Savannah River. The resulting radiation doses to the off-site maximum individual and the off-site population within 80 km of the SRS are estimated on a yearly basis. These estimates are currently generated using dose models prescribed for the commercial nuclear power industry by the Nuclear Regulatory Commission (NRC). The NRC provides default values for dose-model parameters for facilities without resources to develop site-specific values. A survey of land- and water-use characteristics for the Savannah River area has been conducted to determine site-specific values for water recreation, consumption, and agricultural parameters used in the NRC Regulatory Guide 1.109 (1977) dosimetric models. These site parameters include local characteristics of meat, milk, and vegetable production; recreational and commercial activities on the Savannah River; and meat, milk, vegetable, and seafood consumption rates. This paper describes how parameter data were obtained at the Savannah River Site and the impacts of such data on off-site dose. Dose estimates using site-specific parameter values are compared to estimates using the NRC default values

  12. Sensitivity of NTCP parameter values against a change of dose calculation algorithm

    International Nuclear Information System (INIS)

    Brink, Carsten; Berg, Martin; Nielsen, Morten

    2007-01-01

    Optimization of radiation treatment planning requires estimations of the normal tissue complication probability (NTCP). A number of models exist that estimate NTCP from a calculated dose distribution. Since different dose calculation algorithms use different approximations the dose distributions predicted for a given treatment will in general depend on the algorithm. The purpose of this work is to test whether the optimal NTCP parameter values change significantly when the dose calculation algorithm is changed. The treatment plans for 17 breast cancer patients have retrospectively been recalculated with a collapsed cone algorithm (CC) to compare the NTCP estimates for radiation pneumonitis with those obtained from the clinically used pencil beam algorithm (PB). For the PB calculations the NTCP parameters were taken from previously published values for three different models. For the CC calculations the parameters were fitted to give the same NTCP as for the PB calculations. This paper demonstrates that significant shifts of the NTCP parameter values are observed for three models, comparable in magnitude to the uncertainties of the published parameter values. Thus, it is important to quote the applied dose calculation algorithm when reporting estimates of NTCP parameters in order to ensure correct use of the models

  13. Caracterização da dose letal mínima por irradiação gama para Penicillium citrinum Characterization of minimum lethal dosis of gama irradiation to Penicillium citrinum

    Directory of Open Access Journals (Sweden)

    A. N. Norberg

    1993-12-01

    Full Text Available O uso das radiações ionizantes na destruição de microrganismos responsáveis pela deterioração de alimentos ou causadores de infecções ou toxinfecções alimentares, constituiu-se aplicação da energia nuclear, para fins verdadeiramente pacíficos. Penicillium citrinum é um fungo produtor de micotoxinas, responsáveis por intoxicações em humanos e animais que se utilizam de alimentos contaminados. Há escassez de informações sobre a resistência do P. citrinum à irradiação gama; assim esta pesquisa objetivou determinar a dose letal por irradiação gama para esse microrganismo. Foram irradiadas 76 suspensões, contendo aproximadamente 100.000 esporos por mililitro, com doses entre 0,2 e 2,2 KGy (KiloGray, sendo os sobreviventes re-irradiados com doses até 3,0 KGy. O fungo foi totalmente destruído com dose de 2,2 KGy. P. citrinum descendentes dos sobreviventes de 2,0 KGy, quando re-irradiados também foram totalmente destruídos com dose de 2,2 KGy. Observou-se um aumento da resistência às doses mais baixas em relação ao fungo não irradiadoThe use of nuclear power through radiation for the destruction of microrganisms which cause food decay, and toxicosis, is specifically for peaceful purposes. Penicillium citrinum is a fungus which produce mycotoxins responsible for intoxication in humans and animals as a result of eating contaminated food. There is little informations on the resistance of P. citrinum to radiation. The objective of this research is to determine the lethal dose of gama radiation for these microrganisms. Seventy six suspensions containing approximately 100,000 spores/ml received a dose of radiation between 0.2 and 2.2 KGy (KiloGray, being one sample still alive re-irradiated with doses up to 3.0 KGy. The fungus were totally destroyed with a 2.2 KGy. Seventy six suspensions containing approximately 100,000 spores/ml received a dose of radiation between 0.2 and 2.2 KGy, being one sample still alive re

  14. Determination of carcinogenic threshold limit values using the tumorigenic dose rate 50% (TD50)

    International Nuclear Information System (INIS)

    Bonvalot, Y.; Oudiz, A.; Hubert, P.; Abenhaim, L.

    1989-01-01

    The objective of the present study is to propose a simple procedure for the determination of Occupational Limit Values (OLVs) based on the TD 50 concept (Tumorigenic Dose Rate 50%). The TD 50 concept was introduced by Peto R. and al. to help classify chemical substances according to their carcinogenic potency. The TD 50 is that dose rate (in mg/KXg body weight/day) which, if administered chronically for the standard lifespan of the species will halve the probability of remaining tumorless throughout that period. Using TD 50 values available for 776 substances, the procedure presented here allows one to determine OLVs corresponding to a fixed excess risk. It is based on a mathematical high-to-low doses extrapolation of the TD 50 . OLVs obtained with this procedure are compared with currently available TLVs and other occupational guidelines. (author)

  15. Relative effect of dose-rate values and fractionation on late responding tissues and tumours

    International Nuclear Information System (INIS)

    Malgieri, F.

    1995-01-01

    There are currently available different facilities for radiotherapy also with regard to the dose-rate values (in the ranges LDR - MDR - HDR), sometimes used alternatively or subsequently for the same tumour. We have set up a 'unitary' L-Q model, based on Liversage's and Dale's works, that explicitly include also the dose-rate value and a correction factor of the β parameter depending on the sublethal damage repair time constant, on the length of time of each irradiation and on the time interval between following irradiation for to realize the effect of the incomplete repair when the time interval is short as, for example, in the PLDR. This 'unitary' L-Q model is, of course, usable in the same way both for external beam therapy and for curietherapy and make possible to compute and compare, for each kind of tumour and normal tissue, the relative effect of the different available modality of radiotherapy also with regard to the dose-rate. We show and discuss the resulting relationships of the ratio BED 'late'/BED tumour changing the time-dose parameters and the values of the biological characteristic parameters T p , α/β and μ, for defined size of tumour control and different value of the doserate

  16. ALARA database value in future outage work planning and dose management

    International Nuclear Information System (INIS)

    Miller, D.W.; Green, W.H.

    1995-01-01

    ALARA database encompassing job-specific duration and man-rem plant specific information over three refueling outages represents an invaluable tool for the outage work planner and ALARA engineer. This paper describes dose-management trends emerging based on analysis of three refueling outages at Clinton Power Station. Conclusions reached based on hard data available from a relational database dose-tracking system is a valuable tool for planning of future outage work. The system's ability to identify key problem areas during a refueling outage is improving as more outage comparative data becomes available. Trends over a three outage period are identified in this paper in the categories of number and type of radiation work permits implemented, duration of jobs, projected vs. actual dose rates in work areas, and accuracy of outage person-rem projection. The value of the database in projecting 1 and 5 year station person-rem estimates is discussed

  17. ALARA database value in future outage work planning and dose management

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.W.; Green, W.H. [Clinton Power Station Illinois Power Co., IL (United States)

    1995-03-01

    ALARA database encompassing job-specific duration and man-rem plant specific information over three refueling outages represents an invaluable tool for the outage work planner and ALARA engineer. This paper describes dose-management trends emerging based on analysis of three refueling outages at Clinton Power Station. Conclusions reached based on hard data available from a relational database dose-tracking system is a valuable tool for planning of future outage work. The system`s ability to identify key problem areas during a refueling outage is improving as more outage comparative data becomes available. Trends over a three outage period are identified in this paper in the categories of number and type of radiation work permits implemented, duration of jobs, projected vs. actual dose rates in work areas, and accuracy of outage person-rem projection. The value of the database in projecting 1 and 5 year station person-rem estimates is discussed.

  18. Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

    Energy Technology Data Exchange (ETDEWEB)

    Rawl, Richard R [ORNL; Scofield, Patricia A [ORNL; Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL

    2010-04-01

    The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU clause can also have important economic implications for co-mined ores and products that are not intended for the fuel cycle but that have uranium extracted as part of their industrial processing. In examination of the footnotes in Table 2 of TS-R-1, which identifies the progeny included in the exempt or A1/A2 values, there is no explanation of how the progeny were selected. It is recommended that the progeny for both the exemption and A{sub 1}/A{sub 2} values should be similar regardless of application, and that the same physical information should be used in deriving the limits. Based on the evaluation of doses due to the transport of low

  19. Finger doses during interventional radiology: The value of flexible protective gloves

    International Nuclear Information System (INIS)

    Vehmas, T.

    1991-01-01

    Finger doses of radiologists and assistants during 19 interventional radiological procedures were measured with thermoluminescent dosimeters (TLDs), and two types of flexible protective gloves were compared with each other. There were considerable differences in doses between different sites of TLDs on fingers. The exact site of TLDs on hands/fingers should thus be reported in papers. Both gloves were also irradiated through an Alderson phantom and the attenuation values were measured. The gloves with slightly greater attenuation proved to be significantly less comfortable to use. Wearing flexible protective gloves did not lengthen screening times as compared to a previous study in the same department. Various aspects of using such gloves are discussed. The attenuation values of gloves reported by the manufacturers may not apply under all clinical circumstances. (orig.) [de

  20. Comparison of internal dose estimates obtained using organ-level, voxel S value, and Monte Carlo techniques

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, Joshua, E-mail: grimes.joshua@mayo.edu [Department of Physics and Astronomy, University of British Columbia, Vancouver V5Z 1L8 (Canada); Celler, Anna [Department of Radiology, University of British Columbia, Vancouver V5Z 1L8 (Canada)

    2014-09-15

    Purpose: The authors’ objective was to compare internal dose estimates obtained using the Organ Level Dose Assessment with Exponential Modeling (OLINDA/EXM) software, the voxel S value technique, and Monte Carlo simulation. Monte Carlo dose estimates were used as the reference standard to assess the impact of patient-specific anatomy on the final dose estimate. Methods: Six patients injected with{sup 99m}Tc-hydrazinonicotinamide-Tyr{sup 3}-octreotide were included in this study. A hybrid planar/SPECT imaging protocol was used to estimate {sup 99m}Tc time-integrated activity coefficients (TIACs) for kidneys, liver, spleen, and tumors. Additionally, TIACs were predicted for {sup 131}I, {sup 177}Lu, and {sup 90}Y assuming the same biological half-lives as the {sup 99m}Tc labeled tracer. The TIACs were used as input for OLINDA/EXM for organ-level dose calculation and voxel level dosimetry was performed using the voxel S value method and Monte Carlo simulation. Dose estimates for {sup 99m}Tc, {sup 131}I, {sup 177}Lu, and {sup 90}Y distributions were evaluated by comparing (i) organ-level S values corresponding to each method, (ii) total tumor and organ doses, (iii) differences in right and left kidney doses, and (iv) voxelized dose distributions calculated by Monte Carlo and the voxel S value technique. Results: The S values for all investigated radionuclides used by OLINDA/EXM and the corresponding patient-specific S values calculated by Monte Carlo agreed within 2.3% on average for self-irradiation, and differed by as much as 105% for cross-organ irradiation. Total organ doses calculated by OLINDA/EXM and the voxel S value technique agreed with Monte Carlo results within approximately ±7%. Differences between right and left kidney doses determined by Monte Carlo were as high as 73%. Comparison of the Monte Carlo and voxel S value dose distributions showed that each method produced similar dose volume histograms with a minimum dose covering 90% of the volume (D90

  1. Validation of mean glandular dose values provided by a digital breast tomosynthesis system in Brazil

    International Nuclear Information System (INIS)

    Beraldo O, B.; Paixao, L.; Donato da S, S.; Araujo T, M. H.; Nogueira, M. S.

    2014-08-01

    Digital breast tomosynthesis (DBT) is an emerging imaging modality that provides quasi-three-dimensional structural information of the breast and has strong promise to improve the differentiation of normal tissue and suspicious masses reducing the tissue overlaps. DBT images are reconstructed from a sequence of low-dose X-ray projections of the breast acquired at a small number of angles over a limited angular range. The Ho logic Selen ia Dimensions system is equipped with an amorphous Selenium (a-Se) detector layer of 250 μm thickness and a 70 μm pixel pitch. Studies are needed to determine the radiation dose of patients that are undergoing this emerging procedure to compare with the results obtained in DBT images. The mean glandular dose (D G ) is the dosimetric quantity used in quality control of the mammographic systems. The aim of this work is to validate D G values for different breast thicknesses provided by a Ho logic Selen ia Dimensions system using a DBT mode in comparison with the same results obtained by a calibrated 90 X 5-6M-model Radcal ionization chamber. D G values were derived from the incident air kerma (K i ) measurements and tabulated conversion coefficients that are dependent on the half value layer (HVL) of the X-ray spectrum. Voltage and tube loading values were recorded in irradiations using W/Al anode/filter combination, automatic exposure control mode and polymethyl methacrylate (PMMA) slabs which simulate different breast thicknesses. For K i measurements, the ionization chamber was positioned at 655 mm from the focus and the same radiographic technique values were selected with the manual mode. D G values for a complete procedure ranged from 0.9 ± 0.1 to 3.7 ± 0.4 mGy. The results for different breast thicknesses are in accordance with values obtained by DBT images and with acceptable levels established by the Commission of the European Communities (Cec) and the International Atomic Energy Agency (IAEA). This work contributes to

  2. Validation of mean glandular dose values provided by a digital breast tomosynthesis system in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Beraldo O, B.; Paixao, L.; Donato da S, S. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Post-graduation in Sciences and Technology of Radiations Minerals and Materials, Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte (Brazil); Araujo T, M. H. [Dr Maria Helena Araujo Teixeira Clinic, Guajajaras 40, 30180-100 Belo Horizonte (Brazil); Nogueira, M. S., E-mail: bbo@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte (Brazil)

    2014-08-15

    Digital breast tomosynthesis (DBT) is an emerging imaging modality that provides quasi-three-dimensional structural information of the breast and has strong promise to improve the differentiation of normal tissue and suspicious masses reducing the tissue overlaps. DBT images are reconstructed from a sequence of low-dose X-ray projections of the breast acquired at a small number of angles over a limited angular range. The Ho logic Selen ia Dimensions system is equipped with an amorphous Selenium (a-Se) detector layer of 250 μm thickness and a 70 μm pixel pitch. Studies are needed to determine the radiation dose of patients that are undergoing this emerging procedure to compare with the results obtained in DBT images. The mean glandular dose (D{sub G}) is the dosimetric quantity used in quality control of the mammographic systems. The aim of this work is to validate D{sub G} values for different breast thicknesses provided by a Ho logic Selen ia Dimensions system using a DBT mode in comparison with the same results obtained by a calibrated 90 X 5-6M-model Radcal ionization chamber. D{sub G} values were derived from the incident air kerma (K{sub i}) measurements and tabulated conversion coefficients that are dependent on the half value layer (HVL) of the X-ray spectrum. Voltage and tube loading values were recorded in irradiations using W/Al anode/filter combination, automatic exposure control mode and polymethyl methacrylate (PMMA) slabs which simulate different breast thicknesses. For K{sub i} measurements, the ionization chamber was positioned at 655 mm from the focus and the same radiographic technique values were selected with the manual mode. D{sub G} values for a complete procedure ranged from 0.9 ± 0.1 to 3.7 ± 0.4 mGy. The results for different breast thicknesses are in accordance with values obtained by DBT images and with acceptable levels established by the Commission of the European Communities (Cec) and the International Atomic Energy Agency (IAEA

  3. The monetary value of the collective dose equivalent unit (person-rem)

    International Nuclear Information System (INIS)

    Rodgers, Reginald C.

    1978-01-01

    In the design and operation of nuclear power reactor facilities, it is recommended that radiation exposures to the workers and the general public be kept as 'low as reasonably achievable' (ALARA). In the process of implementing this principle cost-benefit evaluations are part of the decision making process. For this reason a monetary value has to be assigned to the collective dose equivalent unit (person-rem). The various factors such as medical health care, societal penalty and manpower replacement/saving are essential ingredients to determine a monetary value for the person-rem. These factors and their dependence on the level of risk (or exposure level) are evaluated. Monetary values of well under $100 are determined for the public dose equivalent unit. The occupational worker person-rem value is determined to be in the range of $500 to about $5000 depending on the exposure level and the type of worker and his affiliation, i.e., temporary or permanent. A discussion of the variability and the range of the monetary values will be presented. (author)

  4. Comparision the value of detecting myocardial viability between low dose dobutamine stress MRI and echocardiography

    International Nuclear Information System (INIS)

    He Yi; Zhang Zhaoqi; Yu Wei; Miao Cuilian; Zhao Yike; Yan Zixu

    2006-01-01

    Objective: To Compare the diagnostic value between low dose dobutamine stress transthrotic echocardiography and low dose dobutamine stress MRI in detecting myocardial viability of chronic myocardial infarction. Methods: Rest and low dose dobutamine (5, 10 μg·kg -1 ·min -1 ) stress transthrotic echocardiography and cine-MRI were performed in 30 patients with chronic myocardial infarction. 24 patients underwent successful revascularization and 10 of them underwent another rest cine-MRI study to assess segmental myocardial functional recovery. Left ventricular were divided into 16 segments, the criteria of viability in different techniques is: MRI: dobutamine induced systolic wall thickening was ≥2 mm in akinetic or diskinetic segments at rest; Echocardiography: wall motion score reduced at least 1 after dobutamine stress in akinetic or' diskinetic segments at rest. Results: One hundren and eight segments showed wall motion abnormalities of 30 patients, 65 and 56 segments shows positive reaction, 43 and 52 segments shows negativereaction in MRI and echocardiography after dobutamine stress respectively. Kappa value of the two techniques is 0.75, concordance in both techniques is 88%. Twenty-four segments showed functional recovery, 14 segments remained dysfunction 3-6 months after revascularization, the sensitivity, specificity and accuracy of detecting myocardial viability in chronic myocardial infarction in MRI and echocardiography is 95.8% vs 79.2% (P>0.05), 85.7% vs 85.7% (P>0.05), 92.1% vs 81.6% (P>0.05) respectively. The sensitivity and accuracy of MRI is a little higher. Conclusion: The ability of detecting myocardial viability by both low dose dobutamine stress transthrotic echocardiography and low dose dobutamine stress MRI is similer, the sensitivity and accuracy of MRI is a little higher. (authors)

  5. Influence of lung parameter values for the Brazilian population on inhalation dose

    International Nuclear Information System (INIS)

    Reis, Arlene A.; Lopes, Ricardo T.

    2009-01-01

    The Human Respiratory Tract Model (HRTM) proposed by the ICRP Publication 66 accounts for the morphology and physiology of the respiratory tract. The ICRP 66 presents deposition fraction in the respiratory tract regions considering reference values from Caucasian man. However, in order to obtain a more accurate assessment of intake and dose the ICRP recommends the use of specific information when they are available. The main objective of this study is to evaluate the influence in dose calculation to each region of the respiratory tract when physiological parameters from samples of Brazilian population, in different levels of exercise, are applied in the deposition model.The dosimetric model of HRTM was implemented in the software EXCEL for Windows and committed equivalent dose was determined for each respiratory tract region. First it was calculated the total number of nuclear transformations considering the fractional deposition of activity in each source tissue obtained by application of physiological and morphological Brazilian parameters in the deposition model and then it was calculated the total energy absorbed per unit mass in the target tissue.The variation in the fractional deposition in the compartments of the respiratory tract in changing the physiological parameters from Caucasian to Brazilian adult man causes variation in the number of total transformations and also in the equivalent dose in each region of the respiratory tract. The variations are not the same for all regions of the respiratory tract and depend on levels of exercise. (author)

  6. Cholinesterase response in the rhabdomyosarcoma tumor and small intestine of the BALB/c mice and the radioprotective actions of exogenous ATP after lethal dose of neutron radiation

    International Nuclear Information System (INIS)

    Szeinfeld, D.; De Villiers, N.

    1993-01-01

    The rhabdomyosarcoma tumors were subjected to different doses of 2.0, 3.8 and 7.0 Gy from a neutron beam facility p(66 MeV)/Be. Elevated levels of cholinesterase activity are observed in which there is a correlation between the different doses of neutron radiation and the augmentation response of this enzyme. The increase of cholinesterase activity after 7 Gy neutron irradiation as a feature of involvement in the homeostatic mechanism maintaining the proper choline/acetylcholine ratio in the cell is also observed at 1 and 24 h in both tissues, rhabdomyosarcoma and small intestine. The activity of the enzyme after neutron irradiation with prior administration of ATP showed smaller increases when compared with increase observed after neutron irradiation alone. Moreover in the present work the protective mechanism of ATP in the response of cholinesterase activity is marked differential between both, normal and tumoral tissue and correlated inversely with the administered of the following concentrations of exogenous ATP (8, 25, 80, 250, and 700 mg/kg body weight) prior to exposure to 7 Gy neutron radiation. These results reflect the radioprotective ability of exogenous ATP to exert a number of metabolic adaptations as a defense mechanism in which the cell exposed to neutron radiation could remain viable because the injury is potentially repairable. (orig.) [de

  7. Early changes in GABA and dlutamine levels and aminotransferase activity in rat brain after total-body γ-irradiation with absolutely lethal doses

    International Nuclear Information System (INIS)

    Rozanov, V.A.; Karpovich, G.A.

    1985-01-01

    The contents of gaama-aminobutyric acid (GABA) and glutamate (GL) as well as GABA-aspartate- and alanine aminotransferase activities were measured in rat cerebellum, cerebral cortex and truncus cerebri 1, 3, 6, 24 and 48 hr following total-body γ-irradiation ( 60 Co) with a dose of 30 Gy. All the indices under study changed in a similar way in the cortex and truncus cerebri while in the cerebellum, GABA level increased and GABA-α-ketoglutarate aminotransfearse activity decreased 60 min after irradiation. The levels of GABA and GL in the cortex and truncus cerebri decreased immediately and increased 24 hr after irradiation. Activity of aminotransferases changed in a phase manner: changes in aspartate- and alanine aminotransferase activity were more pronounced than those of GABA-α-ketoglutarate aminotransferase activity and correlated with the glutamate level changes

  8. Dose estimation in CT exams of the abdomen based on values of DLP; Estimativa da dose em exames de tomografia de abdome com base nos valores de DLP

    Energy Technology Data Exchange (ETDEWEB)

    Kikuti, C.F.; Medeiros, R.B.; Salvadori, P.S.; Costa, D.M.C; D' lppolito, G., E-mail: kikuticf@gmail.com, E-mail: rbitelli2011@gmail.com [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Coordenadoria de Fisica e Higiene das Radiacoes. Departamento de Diagnostico por Imagem

    2013-10-01

    One of the challenges of multidetector computerized tomography is to minimize the risk of ionizing radiation using optimized protocols since higher doses are necessary to obtain high image quality. It was also noted that, due to the geometry in image acquisition using MDCT becomes necessary to estimate dose values consistent with the hypothesis clinically and with the specificities of the tomographic equipment. The aim of this study was to estimate the doses in abdomen exams from the data recorded on the MDCT console and dimensions obtained from DICOM images of patients undergoing different clinical protocols. Were collected, from the image DICOM of 101 exams, values of the dose length product (DLP) provided by Philips Health Care - Brilliance 64 equipment console, in order to relate them with the dose values obtained by means of thermoluminescent dosimeters ( TLD ) of CasSo{sub 4}:Mn placed on the surface of a cylindrical simulator abdomen acrylic manufactured under the technical - operational conditions for a typical abdomen exam. From the data obtained, it was possible to find a factor of 1.16 ( 5 % ) indicating that the DLP values Brilliance 64 console underestimate the doses and this should be used with correction factor to estimate the total dose of the patient. (author)

  9. Analysis of cell cycle regulated and regulating proteins following exposure of lung derived cells to sub-lethal doses of a-rays

    Science.gov (United States)

    Trani, D.; Claudio, P. P.; Cassone, M.; Lucchetti, C.; D'Agostino, L.; Caputi, M.; Giordano, A.

    Introduction Since the last century mankind had to face an increased exposure to man made and natural sources of radiation Radiation represents a therapeutic instrument for radiosensitive cancers as well as a cytotoxic agent for normal human tissues The effects of prolonged exposure to low doses of high energy radiation are still not well-known at the molecular and clinical level Understanding their molecular effects will aid in developing more tailored therapeutic strategies as well as implementing radio-protective measures essential prerequisite for the long-time permanence of men in space Objective of the study The general aim of this study was to evaluate the susceptibility and the response of lung epithelial cells to DNA damage induced by ionizing radiations We decided to study a panel of epithelial bronchial cell lines because of their fast-growth rate and their prominent exposure to both environmental and medical radiations The specific objective of our study was to qualitatively and semi-quantitatively assess the involvement and behaviour of selected genes in DNA damage DNA-repair mechanisms and apoptosis which follow radiation exposure with the aim to determine the involvement of the most promising targets for the early detection of radiation-mediated lung damage before chronic disease develops Methods Four epithelial cell lines one normal and three neoplastic were selected in order to detect and compare survival cell cycle and protein expression differences related to their different genetic asset

  10. The application and shielding value of low-dose CT scanning in hypoxic ischemic encephalopathy of neonate

    International Nuclear Information System (INIS)

    Wu Aiqin; Zheng Wenlong; Xu Chongyong; Cheng Jianmin; Chen Yu; Chen Tinggang

    2006-01-01

    Objective: To investigate the application and shielding value of multi-slice spiral CT scanning with low-dose in hypoxic ischemic encephalopathy (HIE) of neonate. Methods: 60 neonates with HIE diagnosed by clinic were prospectively selected and randomly divided into two groups averagely. The technical parameters were tube tension 120 kV, slice thickness and gap 6 mm, conventional tube current 250 mAs and low dose 50 mAs. Weighted CT dose index (CTDI w ) and dose length product (DLP) were compared to each other. The image noise were analyzed with water phantom of children's skull. The mean and standard deviation of CT value were statistically analyzed. The image quality was blindly evaluated in two different dose groups. Results: (1) The mAs, CTDI w and DLP in low dose group were 20 % of conventional dose group; (2) The noise of water phantom in low dose group was larger than in conventional dose group with the significant difference (t=34.533, P < 0.01 ); (3) The imaging quality in low dose group was mostly better, but inferior to conventional dose group, while there is no poor images to influence the diagnosis of HIE. Conclusions: The low dose scanning will be practical in diagnosis of HIE, and beneficial to protect the newborn which corresponds to the optimizing principle of ICRP in medical radiation protection. (authors)

  11. Dose and image quality in low-dose CT for urinary stone disease: added value of automatic tube current modulation and iterative reconstruction techniques

    International Nuclear Information System (INIS)

    Soenen, Olivier; Balliauw, Christophe; Oyen, Raymond; Zanca, Federica

    2017-01-01

    The aim of this study was to compare dose and image quality (IQ) of a baseline low-dose computed tomography (CT) (fix mAs) vs. an ultra-low-dose CT (automatic tube current modulation, ATCM) in patients with suspected urinary stone disease and to assess the added value of iterative reconstruction. CT examination was performed on 193 patients (103 baseline low-dose, 90 ultra-low-dose). Filtered back projection (FBP) was used for both protocols, and Sinogram Affirmed Iterative Reconstruction (SAFIRE) was used for the ultra-low-dose protocol only. Dose and ureter stones information were collected for both protocols. Subjective IQ was assessed by two radiologists scoring noise, visibility of the ureter and overall IQ. Objective IQ (contrast-to-noise ratio, CNR) was assessed for the ultra-low-dose protocol only (FBP and SAFIRE). The ultra-low-dose protocol (ATCM) showed a 22% decrease in mean effective dose ( p < 0.001) and improved visibility of the pelvic ureter (p = 0.02). CNR was higher for SAFIRE (p < 0.0001). SAFIRE improves the objective IQ, but not the subjective IQ for the chosen clinical task. (authors)

  12. Using ionising radiation against terrorism and contrabandage determination of the occurring dose values

    International Nuclear Information System (INIS)

    Hupe, O.; Ankerhold, U.

    2006-01-01

    Full text of publication follows: Presently the combat against terrorism and contrabandage is gaining in importance. This leads to a growing need for human inspections for weapons or chemical substances like drugs or explosives at e.g. airports and federal buildings. Up to now, this has been done mainly by pat search or the use of metal detectors. But the installed metal detection systems can have a high rate of false alerts, caused e.g. by belt buckles, leading to a high rate of time consuming manual follow-up checks. Also, it is not possible to detect chemical substances or modern plastic weapons. Therefore, a lot of efforts have been made to develop reliable technologies for passenger and cargo controls. Up to now, the demands placed on control systems for the use in routine are fulfilled only by X-ray screening systems. X-ray scanners have been used successfully for several years for personnel controls (checks) at diamond mines and prisons or as cargo scanner. So far, however, these systems have not been used frequently for human inspections, e.g. at airports. In general, two aspects must be considered wit h regard to the use of X-ray personnel scanners: the privacy aspect, because the body shape is seen, and the radiation protection aspect. For radiation protection purposes, and to observe the prescribed dose limits, it is extremely important to know the dose a person gets knowingly when passing a personnel scanner or, as a stowaway, a cargo scanner. Within the scope of a research project measurements were performed on different types of personnel and cargo scanners, using the transmission and backscattering method. All scanners investigated work with a high dose rate and use a short irradiation time. Because of this technique, reliable values of the personal and ambient dose equivalent, H p (10) and H * (10), could be determined only with a specially developed measuring system (presented in a poster at this conference). The scanner systems and dose values

  13. CAN INITIAL βHCG VALUES PREDICT THE NEED FOR SECOND DOSE OF METHOTREXATE IN MEDICAL MANAGEMENT OF ECTOPIC PREGNANCY?

    Directory of Open Access Journals (Sweden)

    Priya Narayanan

    2016-09-01

    Full Text Available INTRODUCTION Prediction of requirement of second dose of methotrexate in patients treated with single dose would help in guiding treatment and counseling. The aim of this study is to determine whether pretreatment beta HCG values can predict the need for second dose of methotrexate in medically managed ectopic pregnancy. MATERIALS AND METHODS 46 women with ectopic pregnancies who were managed medically were included. The median of beta HCG titres on day 1, day 4 and day 7 was assessed in patients who responded to single dose methotrexate and those who required a second dose. RESULTS Out of the 46 patients studied, 41 responded to medical treatment (success 91%. 14 out of 41 required second dose of methotrexate (34%. Two patients required third dose of methotrexate. Five patients required surgery. DISCUSSION The median of day 1 and day 4 beta HCG values were not statistically different between those who responded to single dose methotrexate and those who required a second dose. Only day 7 values were found to be different. CONCLUSION The beta-hCG titre on day 1 and day 4 is not a predictor of requirement of second dose of methotrexate.

  14. Efficacy of single dose of a bivalent vaccine containing inactivated Newcastle disease virus and reassortant highly pathogenic avian influenza H5N1 virus against lethal HPAI and NDV infection in chickens.

    Directory of Open Access Journals (Sweden)

    Dong-Hun Lee

    Full Text Available Highly pathogenic avian influenza (HPAI and Newcastle disease (ND are 2 devastating diseases of poultry, which cause great economic losses to the poultry industry. In the present study, we developed a bivalent vaccine containing antigens of inactivated ND and reassortant HPAI H5N1 viruses as a candidate poultry vaccine, and we evaluated its immunogenicity and protective efficacy in specific pathogen-free chickens. The 6:2 reassortant H5N1 vaccine strain containing the surface genes of the A/Chicken/Korea/ES/2003(H5N1 virus was successfully generated by reverse genetics. A polybasic cleavage site of the hemagglutinin segment was replaced by a monobasic cleavage site. We characterized the reverse genetics-derived reassortant HPAI H5N1 clade 2.5 vaccine strain by evaluating its growth kinetics in eggs, minimum effective dose in chickens, and cross-clade immunogenicity against HPAI clade 1 and 2. The bivalent vaccine was prepared by emulsifying inactivated ND (La Sota strain and reassortant HPAI viruses with Montanide ISA 70 adjuvant. A single immunization with this vaccine induced high levels of hemagglutination-inhibiting antibody titers and protected chickens against a lethal challenge with the wild-type HPAI and ND viruses. Our results demonstrate that the bivalent, inactivated vaccine developed in this study is a promising approach for the control of both HPAI H5N1 and ND viral infections.

  15. ON THE ADVISABILITY OF REJECTION OF SUBTRACTION OF BACKGROUND DOSIMETERS INDICATION VALUES FROM THE MEASURED VALUES OF INDIVIDUAL DOSES OF OCCUPATIONAL EXPOSURE OF A-GROUP PERSONNEL

    Directory of Open Access Journals (Sweden)

    A. N. Barkovskiy

    2013-01-01

    Full Text Available An article contains substantiation of advisability of rejection of subtraction of background dosimeters indication values from the measured values of individual doses of occupational exposure of A-group personnel in the process of carrying out of individual dosimetry control of medical organizations stuff which was implemented in the Methodical Guideline 2.6.1.3015-12. It is shown that mentioned procedure is firstly incorrect when we deal with low doses, when the impact of natural exposure could be really considerable and secondary senseless when we deal with dose values close to the dose limit value for A-group personnel when the impact of natural exposure is much lower then the error of measurements. It is suggested to carry out the account of the impact of natural exposure into personnel average doses basing on the analysis of statistical distributions of personnel individual doses and on indications of background dosimeters. It is suggested to add the information about indications of background dosimeters into the Base of Federal Statistical Supervision № 1-DOS as it is prescribed in the Methodical Guideline 2.6.1.3015-12. This article is the respond to the article of A.I. Grigoriev published in the present issue of Journal, in which the author contests the reasonableness of this provision.

  16. Review of proposed values for carcinogenic effects of low dose irradiation: calculations and sensitivity analysis

    International Nuclear Information System (INIS)

    Hubert, P.

    1983-01-01

    The assessment of radiological risk generally relies on no threshold linear relationship, computed by the ICRP and the National Academy of Science in a former report (BEIR II). The last report of the NAS, as well as the publication by Loewe and Mendelsohn of new dose estimates for Hiroshima and Nagasaki, enhanced the controversy on the shape of the curve of the dose effect relationship. The theoretical debate focuses on this shape (linear or quadratic, with or without threshold) which depends on the true impact of radiation in the carcinogenic process. This paper leaves aside the theoretical aspect of the problem. Instead, it describes the flow chart of the calculations which allow to find munerical values for the coefficients of the relationship, starting from the observations on irradiated human populations. In this process, besides the theoretical hypotheses, pragmatic choices, and even the necessary simplifications in the calculation, can result in substantial changes in the risk coefficients. This paper aims to present these factors of variability, as well as some sensitivity analyses. These analyses are performed within the framework of pragmatical problems like the assessment of radiological impact of nuclear facilities or the optimisation of radioprotection. In this respect, the shape of the curve appears not to have greater impact than other alternatives, such as the absolute v relative risk projection model, the choice of data source [fr

  17. Marked bengal pink. A dynamic test using marking doses; its value in jaundice diagnosis

    International Nuclear Information System (INIS)

    Kellershohn, C.; Desgrez, A.; Delaloye, B.

    1961-01-01

    The authors do a historic calling back of the differential study of jaundices thanks to the semi logarithmic gradients of expurgation of bromine sulphone-phthalein and thanks to the time of appearance of this material in the bile collected by duodenal tubing. They sum up likewise the foreign works which lead to take the place of this test, the outside count at the level of the head, the liver, and the abdomen after intravenous injection of a running dose of marked Rose Bengal. They specify the technical conditions of this test and report an experience which corroborate its value, its accuracy and the interest of its using in the different types of jaundices (hepatitis and obstructive types). (author) [fr

  18. Features of working in fields with high values of exposure dose rate

    International Nuclear Information System (INIS)

    Samojlenko, Yu.N.

    1989-01-01

    Features of working in fields with the exposure dose rate (EDR) ∼ 1000-7000 R/h are described. Data on the performed operations concerning initial decontamination of the Chernobyl-3 reactor roof during 10.07.86-03.10.86 are presented. It is marked that the methodical recommendations on working in fields with high values of EDR are absent in our country and abroad and it is necessary to develop them on the basis of obtained experience. Moreover, there are no protective means (protective clotting). Main principles of its creation are the protection of critical organ groups and comfort in working. Personnel should be specially trained and get phychologically ready. 2 figs., 1 tab

  19. Quantitative aspects of repair of potentially lethal damage in mammalian cells

    International Nuclear Information System (INIS)

    Iliakis, G.; Pohlit, W.

    1979-01-01

    Stationary cultures of Ehrlich ascites tumour cells were irradiated with X-rays and then immediately or after a time interval tsub(rep) plated to measure the survival. The increase in survival observed after delayed plating was interpreted as repair of potentially lethal damage. A cybernetic model was used to analyse these data. Three states of damage were assumed for the cells. In state A the cells could grow to macrocolonies, in state B the cells suffered potentially lethal damage and could grow to macrocolonies only if they were allowed to repair the damage and in state C the cells were lethally damaged. A method of deriving the values of the parameters of the model from the experimental data was given. The dependence of the reaction rate constant of the repair potentially lethal damage on the dose D was used to derive a possible mechanism for the production of the shoulder in the dose effect curve. Finally this model was compared with other models of radiation action in living cells. (author)

  20. Optimization of the radiation protection: the value of Sv personnel for the occupational doses

    International Nuclear Information System (INIS)

    Sollet SaNudo, E.; Carmena Servet, P.

    1997-01-01

    Publication 60 of the International Commission on Radiological Protection (ICRP) points out that most of the methods used in the optimization tend to emphasize the benefits and the detriment to society. The benefits and the detriments are unlikely to be distributed through the society in the same way. Optimization of protection may thus introduce a substantial inequity between one individual and another. To avoid this, the optimization principle is now formulated by ICRP as follows. The magnitude of the individual doses, the number of people exposed, and the likelihood of incurring exposures where are not certain to be received should be kept as low as reasonably achievable, economic and social factors being taken into account. This procedure should be constrained by restrictions on the doses to individuals or the risks to individuals, so as to limit the inequity likely to result from the inherent economic and social judgments. Beyond the optimal reduction of the collective exposure, now ICRP 60 recommends to reduce the number of persons exposed and the scatter of individual exposures. It is implicit in this recommendation that the high priority must be given to the highest individual exposures. Now the decision is made; in case of conflict, reduction of individual exposures should go first than reduction of collective exposures. In order to implement the optimization principle, this article suggests the introduction of a system to compute the reference monetary values of the person, sievert satisfying the new ICRP recommendations and ensuring a global coherence within the whole system of radiological protection. (Author) 13 refs

  1. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities

    International Nuclear Information System (INIS)

    Peters, Diane E.; Hoover, Benjamin; Cloud, Loretta Grey; Liu, Shihui; Molinolo, Alfredo A.; Leppla, Stephen H.; Bugge, Thomas H.

    2014-01-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5–3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. - Highlights: • Toxicity and anti

  2. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities.

    Science.gov (United States)

    Peters, Diane E; Hoover, Benjamin; Cloud, Loretta Grey; Liu, Shihui; Molinolo, Alfredo A; Leppla, Stephen H; Bugge, Thomas H

    2014-09-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5-3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. Published by Elsevier Inc.

  3. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Diane E. [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Program of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA (United States); Hoover, Benjamin [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Cloud, Loretta Grey [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Liu, Shihui [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Molinolo, Alfredo A. [Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Leppla, Stephen H. [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Bugge, Thomas H., E-mail: thomas.bugge@nih.go [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States)

    2014-09-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5–3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. - Highlights: • Toxicity and anti

  4. The Evaluation of personnel radiation dose and society radiation on RSG-GAS around as proposal determination of ALARA value

    International Nuclear Information System (INIS)

    Pande Made Udiyani; Puradwi IW

    2007-01-01

    Each nuclear installation to achieve radiation safety has to meet the ALARA concepts. The ALARA value of a nuclear installation should be enacted by regulator body. ALARA value can be determined by evaluation radiation exposure and dose acceptance of nuclear installation operation. As case study in Indonesia, ALARA assessment in nuclear installation is done at RSG-GAS reactor. Intention of this research is to determine gyration reference assess ALARA by evaluate radiation dose acceptance by RSG-GAS radiation personnel and the influence of RSG-GAS operation to presentation of radiation accepted by society which living around its. ALARA of RSG-GAS determined based on evaluation of measurement data of the radiation doses which is accepted by personnel radiation. While evaluation of radiation doses which is accepted by society in the radius 5 km of the RSG-GAS conducted to data result of calculation using program package of CAP-88 and measurement result with method of carborne survey. Result of radiation dose evaluation obtained which not pass dose definition for the radiation worker that is 50 mSv/year, and for society around RSG-GAS that is 5 mSv/year. Based on the result of evaluation hence obtained value of ALARA for RSG-GAS in value of gyration 17 - 50 mSv/year. (author)

  5. Correction of conebeam CT values using a planning CT for derivation of the 'dose of the day'

    International Nuclear Information System (INIS)

    Zijtveld, Mathilda van; Dirkx, Maarten; Heijmen, Ben

    2007-01-01

    Background and purpose: Verification of the actually delivered 3D dose distribution during each treatment fraction ('dose of the day') is the most complete and clinical relevant 'in-vivo' check of an IMRT treatment. To do this, during patient treatment portal dose images are routinely acquired with our electronic portal imaging device to derive the delivered fluence map for each treatment field. In addition, a conebeam CT scan is acquired just prior to treatment to derive the patient geometry at the time of treatment. However, the use of conebeam CT scans for dose calculation is hampered by inaccuracies in the conversion of CT values to electron densities due to an enlarged scatter contribution. Materials and methods: In this work, a method is described for mapping of Hounsfield Units of the planning CT to the conebeam CT scan, while accounting for non-rigidity in the anatomy, e.g. related to weight loss, in an approximate way. The method was validated for head and neck cancer patients by comparing dose distributions calculated using adjusted Hounsfield Units with a golden standard. Results and conclusions: The observed dose differences were less than 1% in the majority of points, and in at least 96% of the points a 3D γ analysis resulted in γ values of less than 1 when applying a 2%/2 mm criterion, showing that this straightforward approach allows for an accurate dose calculation based on conebeam CT scans

  6. Limiting values for the RBE of fission neutrons at low doses for life shortening in mice

    International Nuclear Information System (INIS)

    Storer, J.B.; Mitchell, T.J.

    1984-01-01

    The authors have analyzed recently published data on the effects of low doses of fission neutrons on the mean survival times of mice. The analysis for single-dose exposures was confined to doses of 20 rad or less, while for fractionated exposures only total doses of 80 rad or less were considered. They fitted the data to the frequently used power function model: life shortening = βD/sup γ/, where D is the radiation dose. They show that, at low doses per fraction, either the effects are not additive or the dose-effect curve for single exposures cannot show a greater negative curvature than about the 0.9 power of dose. Analysis of the data for γ rays showed that an exponent of 1.0 gave an acceptable fit. They conclude that at neutron doses of 20 rad or less the RBE for life shortening is constant and ranges from 13 to 22 depending on mouse strain and sex

  7. Local patient dose diagnostic reference levels in pediatric interventional cardiology in Chile using age bands and patient weight values.

    Science.gov (United States)

    Ubeda, Carlos; Miranda, Patricia; Vano, Eliseo

    2015-02-01

    To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency. Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs. Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there may be large differences in child size. These DRLs were obtained at the largest pediatric hospital in Chile, with an active optimization program, and could be used by other hospitals in the Latin America region to compare their current patient dose values and determine whether corrective action is appropriate. © 2015 American Association of Physicists in Medicine.

  8. Dexmedetomidine reduces pain associated with rocuronium injection without causing a decrease in BIS values: a dose-response study.

    Science.gov (United States)

    Joo, Jin; Baek, Jungwon; Lee, Jaemin

    2014-09-01

    To examine whether dexmedetomidine reduces the injection pain of propofol and rocuronium and to investigate whether the decrease in injection pain is associated with the known sedative action of dexmedetomidine. Randomized, double-blind, placebo-controlled clinical comparison study. Patients undergoing general anesthesia with intubation received 40 mg of 1% lidocaine (lidocaine group; n = 28), 0.25 μg/kg of dexmedetomidine (low-dose group; n = 27), 0.5 μg/kg of dexmedetomidine (subclinical dose group; n = 28), 1.0 μg/kg of dexmedetomidine (clinical dose group, n = 27), or normal saline (saline group; n = 28) before anesthetic induction. Pain associated with propofol and rocuronium injection was assessed using a 10-point verbal analog scale (VAS) and a 4-point withdrawal movement scale, respectively. The BIS value was measured 60 seconds after administration of the study drug, and at the time of rocuronium injection and intubation. The overall incidence of withdrawal movements due to rocuronium decreased significantly as the dose of dexmedetomidine increased (92.8%, 85.2%, 78.6%, and 51.9% in the saline, low-dose, subclinical dose, and clinical dose groups, respectively; P = 0.001). There was no significant difference in BIS values among the groups 60 seconds after study drug administration or at the time of rocuronium injection. Dexmedetomidine reduced pain associated with rocuronium injection in a dose-dependent manner. This effect was not associated with the decrease in BIS value. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. In contrast to conventional inactivated influenza vaccines, 4xM2e.HSP70c fusion protein fully protected mice against lethal dose of H1, H3 and H9 influenza A isolates circulating in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi, Seyyed Mahmoud, E-mail: smebrahimi@shirazu.ac.ir [Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, P.O. Box 14155-3651,Tehran (Iran, Islamic Republic of); Research Center of Virus and Vaccine, Baqiyatallah University of Medical Science, P.O.Box 14155-3651, Tehran (Iran, Islamic Republic of); Dabaghian, Mehran [Department of Pathobiology, University of Tehran, Faculty of Veterinary Medicine, P.O. Box 14155-6453, Tehran (Iran, Islamic Republic of); Tebianian, Majid [Department of Biotechnology, Razi Vaccine and Serum Research Institute (RVSRI), P.O. Box 31975/148, Karaj, Tehran (Iran, Islamic Republic of); Zabeh Jazi, Mohammad Hossein [Department of Pathobiology, University of Tehran, Faculty of Veterinary Medicine, P.O. Box 14155-6453, Tehran (Iran, Islamic Republic of)

    2012-08-15

    Ideal vaccines against influenza viruses should elicit not only a humoral response, but also a cellular response. Mycobacterium tuberculosis HSP70 (mHSP70) have been found to promote immunogenic APCs function, elicit a strong cytotoxic T lymphocyte (CTL) response, and prevent the induction of tolerance. Moreover, it showed linkage of antigens to the C-terminus of mHSP70 (mHSP70c) can represent them as vaccines resulted in more potent, protective antigen specific responses in the absence of adjuvants or complex formulations. Hence, recombinant fusion protein comprising C-terminus of mHSP70 genetically fused to four tandem repeats of the ectodomain of the conserved influenza matrix protein M2 (M2e) was expressed in Escherichia coli, purified under denaturing condition, refolding, and then confirmed by SDS-PAGE, respectively. The recombinant fusion protein, 4xM2e.HSP70c, retained its immunogenicity and displayed the protective epitope of M2e by ELISA and FITC assays. A prime-boost administration of 4xM2e.HSP70c formulated in F105 buffer by intramuscular route in mice (Balb/C) provided full protection against lethal dose of mouse-adapted H1N1, H3N2, or H9N2 influenza A isolates from Iran compared to 0-33.34% survival rate of challenged unimmunized and immunized mice with the currently in use conventional vaccines designated as control groups. However, protection induced by immunization with 4xM2e.HSP70c failed to prevent weight loss in challenged mice; they experienced significantly lower weight loss, clinical symptoms and higher lung viral clearance in comparison with protective effects of conventional influenza vaccines in challenged mice. These data demonstrate that C-terminal domain of mHSP70 can be a superior candidate to deliver the adjuvant function in M2e-based influenza A vaccine in order to provide significant protection against multiple influenza A virus strains.

  10. In contrast to conventional inactivated influenza vaccines, 4xM2e.HSP70c fusion protein fully protected mice against lethal dose of H1, H3 and H9 influenza A isolates circulating in Iran

    International Nuclear Information System (INIS)

    Ebrahimi, Seyyed Mahmoud; Dabaghian, Mehran; Tebianian, Majid; Zabeh Jazi, Mohammad Hossein

    2012-01-01

    Ideal vaccines against influenza viruses should elicit not only a humoral response, but also a cellular response. Mycobacterium tuberculosis HSP70 (mHSP70) have been found to promote immunogenic APCs function, elicit a strong cytotoxic T lymphocyte (CTL) response, and prevent the induction of tolerance. Moreover, it showed linkage of antigens to the C-terminus of mHSP70 (mHSP70c) can represent them as vaccines resulted in more potent, protective antigen specific responses in the absence of adjuvants or complex formulations. Hence, recombinant fusion protein comprising C-terminus of mHSP70 genetically fused to four tandem repeats of the ectodomain of the conserved influenza matrix protein M2 (M2e) was expressed in Escherichia coli, purified under denaturing condition, refolding, and then confirmed by SDS–PAGE, respectively. The recombinant fusion protein, 4xM2e.HSP70c, retained its immunogenicity and displayed the protective epitope of M2e by ELISA and FITC assays. A prime-boost administration of 4xM2e.HSP70c formulated in F105 buffer by intramuscular route in mice (Balb/C) provided full protection against lethal dose of mouse-adapted H1N1, H3N2, or H9N2 influenza A isolates from Iran compared to 0–33.34% survival rate of challenged unimmunized and immunized mice with the currently in use conventional vaccines designated as control groups. However, protection induced by immunization with 4xM2e.HSP70c failed to prevent weight loss in challenged mice; they experienced significantly lower weight loss, clinical symptoms and higher lung viral clearance in comparison with protective effects of conventional influenza vaccines in challenged mice. These data demonstrate that C-terminal domain of mHSP70 can be a superior candidate to deliver the adjuvant function in M2e-based influenza A vaccine in order to provide significant protection against multiple influenza A virus strains.

  11. [Value of early application of different doses of amino acids in parenteral nutrition among preterm infants].

    Science.gov (United States)

    Liu, Zhi-Juan; Liu, Guo-Sheng; Chen, Yong-Ge; Zhang, Hui-Li; Wu, Xue-Fen

    2015-01-01

    To study the short-term response and tolerance of different doses of amino acids in parenteral nutrition among preterm infants. This study included 86 preterm infants who had a birth weight between 1 000 to 2 000 g and were admitted to the hospital within 24 hours of birth between March 2013 and June 2014. According to the early application of different doses of amino acids, they were randomized into low-dose group (n=29, 1.0 g/kg per day with an increase of 1.0 g/kg daily and a maximum of 3.5 g/kg per day), medium-dose group (n=28, 2.0 g/kg per day with an increase of 1.0 g/kg daily and a maximum of 3.7 g/kg per day), and high-dose group (n=29, 3.0 g/kg per day with an increase of 0.5-1.0 g/kg daily and a maximum of 4.0 g/kg per day). Other routine parenteral nutrition and enteral nutrition support were also applied. The maximum weight loss was lower and the growth rate of head circumference was greater in the high-dose group than in the low-dose group (Pnutrition, shorter duration of hospital stay, and less hospital cost than those in the low-dose group (P0.05). Parenteral administration of high-dose amino acids in preterm infants within 24 hours after birth can improve the short-term nutritional status of preterm infants, but there is a transient increase in BUN level.

  12. Correlation between Colon Transit Time Test Value and Initial Maintenance Dose of Laxative in Children with Chronic Functional Constipation

    Science.gov (United States)

    Kim, Mock Ryeon; Park, Hye Won; Son, Jae Sung; Lee, Ran

    2016-01-01

    Purpose To evaluate the correlation between colon transit time (CTT) test value and initial maintenance dose of polyethylene glycol (PEG) 4000 or lactulose. Methods Of 415 children with chronic functional constipation, 190 were enrolled based on exclusion criteria using the CTT test, defecation diary, and clinical chart. The CTT test was performed with prior disimpaction. The laxative dose for maintenance was determined on the basis of the defecation diary and clinical chart. The Shapiro-Wilk test and Pearson's and Spearman's correlations were used for statistical analysis. Results The overall group median value and interquartile range of the CTT test was 43.8 (31.8) hours. The average PEG 4000 dose for maintenance in the overall group was 0.68±0.18 g/kg/d; according to age, the dose was 0.73±0.16 g/kg/d (encopresis, abnormal CTT test subtype) for either laxative. Even in the largest group (overall, n=109, younger than 8 years and on PEG 4000), the correlation was weak (Pearson's correlation coefficient [R]=0.268, p=0.005). Within the abnormal transit group, subgroup (n=73, younger than 8 years and on PEG 4000) correlation was weak (R=0.267, p=0.022). Conclusion CTT test value cannot predict the initial maintenance dose of PEG 4000 or lactulose with linear correlation. PMID:27738600

  13. Absorbed dose evaluation of Auger electron-emitting radionuclides: impact of input decay spectra on dose point kernels and S-values.

    Science.gov (United States)

    Falzone, Nadia; Lee, Boon Q; Fernández-Varea, José M; Kartsonaki, Christiana; Stuchbery, Andrew E; Kibédi, Tibor; Vallis, Katherine A

    2017-03-21

    The aim of this study was to investigate the impact of decay data provided by the newly developed stochastic atomic relaxation model BrIccEmis on dose point kernels (DPKs - radial dose distribution around a unit point source) and S-values (absorbed dose per unit cumulated activity) of 14 Auger electron (AE) emitting radionuclides, namely 67 Ga, 80m Br, 89 Zr, 90 Nb, 99m Tc, 111 In, 117m Sn, 119 Sb, 123 I, 124 I, 125 I, 135 La, 195m Pt and 201 Tl. Radiation spectra were based on the nuclear decay data from the medical internal radiation dose (MIRD) RADTABS program and the BrIccEmis code, assuming both an isolated-atom and condensed-phase approach. DPKs were simulated with the PENELOPE Monte Carlo (MC) code using event-by-event electron and photon transport. S-values for concentric spherical cells of various sizes were derived from these DPKs using appropriate geometric reduction factors. The number of Auger and Coster-Kronig (CK) electrons and x-ray photons released per nuclear decay (yield) from MIRD-RADTABS were consistently higher than those calculated using BrIccEmis. DPKs for the electron spectra from BrIccEmis were considerably different from MIRD-RADTABS in the first few hundred nanometres from a point source where most of the Auger electrons are stopped. S-values were, however, not significantly impacted as the differences in DPKs in the sub-micrometre dimension were quickly diminished in larger dimensions. Overestimation in the total AE energy output by MIRD-RADTABS leads to higher predicted energy deposition by AE emitting radionuclides, especially in the immediate vicinity of the decaying radionuclides. This should be taken into account when MIRD-RADTABS data are used to simulate biological damage at nanoscale dimensions.

  14. Diagnostic I-131 scintigraphy in patients with differentiated thyroid cancer. No additional value of higher scan dose

    International Nuclear Information System (INIS)

    Phan, T.T.H.; Tol, K.M. van; Links, T.P.; Piers, D.A.; Vries, E.G.E. de; Dullaart, R.P.F.; Jager, P.L.

    2004-01-01

    After initial treatment with total thyroidectomy and radio iodine ablation, most follow-up protocols for patients with differentiated thyroid carcinoma contain cyclic diagnostic I-131 imaging and serum thyroglobulin (Tg) measurements. The applied diagnostic I-131 doses vary between 37 and 370 MBq. The aim of this study was to determine the yield of a diagnostic scan with 370 MBq I-131 in patients with a negative diagnostic scan with 74 MBq I-131. Retrospective evaluation of 158 patients who received a high-dose diagnostic scan with 370 MBq I-131 because of a negative low-dose diagnostic scan with 74 MBq I-131. Special attention was paid to the patients with positive high-dose diagnostic scanning and undetectable serum Tg levels after thyroid hormone withdrawal. In 127 (80%) of patients the 370 MBq I-131 scan was negative, just like the preceding low-dose scan. In 31 (20%) of patients abnormal uptake was present on the 370 MBq diagnostic scan. In 19 of these 31 patients serum Tg was undetectable. In 15/19 the high-dose diagnostic scan proved either false positive or demonstrated clinically irrelevant minor ablation rests. In only four patients (2.5%) did the high-dose diagnostic scans reveal possibly relevant uptake caused by residual differentiated thyroid cancer. In 98% of patients a 370 MBq dose of I-131 for diagnostic whole-body scintigraphy (WBS) had no additional value. The combination of a low-dose diagnostic I-131 scan using only 74 MBq combined with a serum Tg level measurement proved sufficient for correct clinical decision making regarding whether the patient requires additional I-131 therapy. (authors)

  15. Cell lethality after selective irradiation of the DNA replication fork

    International Nuclear Information System (INIS)

    Hofer, K.G.; Warters, R.L.

    1985-01-01

    It has been suggested that nascent DNA located at the DNA replication fork may exhibit enhanced sensitivity to radiation damage. To evaluate this hypothesis, Chinese hamster ovary cells (CHO) were labeled with 125 I-iododeoxyuridine ( 125 IUdR) either in the presence or absence of aphidicolin. Aphidicolin (5 μg/ml) reduced cellular 125 IUdR incorporation to 3-5% of the control value. The residual 125 I incorporation appeared to be restricted to low molecular weight (sub-replicon sized) fragments of DNA which were more sensitive to micrococcal nuclease attack and less sensitive to high salt DNase I digestion than randomly labeled DNA. These findings suggest that DNA replicated in the presence of aphidicolin remains localized at the replication fork adjacent to the nuclear matrix. Based on these observations an attempt was made to compare the lethal consequences of 125 I decays at the replication fork to that of 125 I decays randomly distributed over the entire genome. Regardless of the distribution of decay events, all treatment groups exhibited identical dose-response curves (D 0 : 101 125 I decays/cell). Since differential irradiation of the replication complex did not result in enhanced cell lethality, it can be concluded that neither the nascent DNA nor the protein components (replicative enzymes, nuclear protein matrix) associated with the DNA replication site constitute key radiosensitive targets within the cellular genome. (orig.)

  16. Histopathological effects of lethal and sub-lethal concentrations of ...

    African Journals Online (AJOL)

    The histopathological effects of lethal and sub-lethal concentrations of glyphosate on African catfish Clarias gariepinus were investigated. C. gariepinus juveniles were assessed in a static renewal bioassay for 96 hours (acute toxicity) and 28 days (chronic toxicity) using varying concentrations (0.0 mg/l 20.0 mg/l, 30.0 mg/l, ...

  17. Local patient dose diagnostic reference levels in pediatric interventional cardiology in Chile using age bands and patient weight values

    Energy Technology Data Exchange (ETDEWEB)

    Ubeda, Carlos, E-mail: cubeda@uta.cl [Medical Technology Department, Radiological Sciences Center, Health Sciences Faculty, Tarapaca University, Arica 1000000 (Chile); Miranda, Patricia [Hemodynamic Department, Cardiovascular Service, Luis Calvo Mackenna Hospital, Santiago 7500539 (Chile); Vano, Eliseo [Radiology Department, Faculty of Medicine, Complutense University and IdIS, San Carlos Hospital, Madrid 28040 (Spain)

    2015-02-15

    Purpose: To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency. Methods: Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs. Results: Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for <1 yr; 213 for 1 to <5 yr; 82 for 5 to <10 yr; and 102 for 10 to <16 yr. The third quartile values obtained for DAP by diagnostic and therapeutic procedures and age range were 1.17 and 1.11 Gy cm{sup 2} for <1 yr; 1.74 and 1.90 Gy cm{sup 2} for 1 to <5 yr; 2.83 and 3.22 Gy cm{sup 2} for 5 to <10 yr; and 7.34 and 8.68 Gy cm{sup 2} for 10 to <16 yr, respectively. The third quartile value obtained for the DAP/body weight ratio for the full sample of procedures was 0.17 (Gy cm{sup 2}/kg) for diagnostic and therapeutic procedures. Conclusions: The data presented in this paper are an initial attempt at establishing local DRLs in pediatric interventional cardiology, from a large sample of procedures for the standard age bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there

  18. Local patient dose diagnostic reference levels in pediatric interventional cardiology in Chile using age bands and patient weight values

    International Nuclear Information System (INIS)

    Ubeda, Carlos; Miranda, Patricia; Vano, Eliseo

    2015-01-01

    Purpose: To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency. Methods: Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs. Results: Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for <1 yr; 213 for 1 to <5 yr; 82 for 5 to <10 yr; and 102 for 10 to <16 yr. The third quartile values obtained for DAP by diagnostic and therapeutic procedures and age range were 1.17 and 1.11 Gy cm 2 for <1 yr; 1.74 and 1.90 Gy cm 2 for 1 to <5 yr; 2.83 and 3.22 Gy cm 2 for 5 to <10 yr; and 7.34 and 8.68 Gy cm 2 for 10 to <16 yr, respectively. The third quartile value obtained for the DAP/body weight ratio for the full sample of procedures was 0.17 (Gy cm 2 /kg) for diagnostic and therapeutic procedures. Conclusions: The data presented in this paper are an initial attempt at establishing local DRLs in pediatric interventional cardiology, from a large sample of procedures for the standard age bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there may be large differences

  19. Fetal organ dosimetry for the Techa River and Ozyorsk Offspring Cohorts. Pt. 2. Radionuclide S values for fetal self-dose and maternal cross-dose

    International Nuclear Information System (INIS)

    Maynard, Matthew R.; Bolch, Wesley E.; Shagina, Natalia B.; Tolstykh, Evgenia I.; Degteva, Marina O.; Fell, Tim P.

    2015-01-01

    One of the many objectives of the European Union's SOLO (Epidemiological Studies of Exposed Southern Urals Populations) project is to quantify the radiation dose-response following chronic in utero exposures to ionizing radiation. The project is presently conducting a pooled analysis of two cohorts of individuals born to exposed mothers - the Techa River Offspring Cohort (TROC) and the Ozyorsk Offspring Cohort (OOC). The TROC includes the offspring of mothers with external exposures to contaminated riverbanks and internal ingestions of 89 Sr, 90 Sr/ 90 Y, and 137 Cs/ 137m Ba, while the OOC includes the offspring of mothers with external exposures seen within the Mayak plutonium production facilities and internal inhalation of 239 Pu and possibly 131 I. In the present study, a newly created Urals-based series of fetal and maternal models is employed to assess S values for all seven radionuclides. Among all fetal ages, S values ranged in magnitude from 10 -14 to 10 -10 Gy per Bq-s for fetal source organs and from 10 -18 to 10 -14 Gy per Bq-s from maternal source organs, depending upon particle type, particle energy, and fetal age. For a given radionuclide and fetal age, S values for fetal source organs were approximately two orders of magnitude higher than for maternal source organs. Little variation in S values was observed among fetal source organs, while variations of over 100 % with respect to the mean were observed for maternal source organs near the fetus. S value variations from maternal cross-fire were highly dependent on fetal position and separation distance from the maternal source organ. These radionuclide S values have been coupled with biokinetic models for use in cohort dose assessment within the SOLO project. (orig.)

  20. Determination of lethal doses 50 and 100 of propofol in lipid emulsion nor nanoemulsion intraperitoneally in miceDeterminação das doses letal 50 e 100 do propofol em nanoemulsão ou em emulsão lipídica pela via intraperitoneal em camundongos

    Directory of Open Access Journals (Sweden)

    Martielo Ivan Gehrcke

    2012-10-01

    Full Text Available The formulation of a drug can interfere with its absorption into the circulatory system and may result in changes in the dose required to achieve that particular effect. The aim of this study was to determine the lethal dose 50 (LD 50 and 100 (LD100 of a nanoemulsion of propofol and the lipid emulsion in mice intraperitoneally. One hundred sixty animals weighing 36.47±4.6g, which were distributed randomly into two groups: NANO and EMU who received propofol 1% in the nanoemulsion and lipid emulsion, respectively, intraperitoneally. Began with a dose of 250mg/kg (n=10 and from this isdecreased or increased the dose until achieving 0 and 100% of deaths in each group thus formed were seven subgroups in NANO (each subgroup n = 10 at doses 200, 250, 325, 350, 400, 425 and 475 mg/kg and in EMU eight subgroups (n= 10 each subset 250, 325, 350, 400, 425, 475, 525 and 575 mg/kg. In the CONTROL group (n=10 animals received saline in the largest volume used in the other groups to rule out death by the volume injected. Analysis of LD 50 and LD 100 were obtained by linear regression. The LD 50 was 320, 95 mg / kg and 4243, 51mg / kg and the LD 100 was445.99 mg / kg and 595.31 mg / kg to groups NANO and EMU, respectively. It follows that nanoemulsion is propofol in 25% more potent compared to the lipid emulsionintraperitoneally. A formulação de um fármaco pode interferir na sua absorção para o sistema circulatório, podendo resultar em alterações da dose necessária para que se consiga determinado efeito. O objetivo deste estudo foi determinar as doses letais 50 (DL 50 e 100 (DL100 do propofol em nanoemulsão e emulsão lipídica em camundongos pela via intraperitoneal. Foram utilizados 160 animais pesando 36,47 ± 4,6g, os quais foram distribuídos aleatoriamente em dois grupos: NANO e EMU que receberam propofol à 1% em nanoemulsão e em emulsão lipídica, respectivamente, pela via intraperitoneal. Iniciou-se com a dose de 250mg/kg (n=10 e a partir

  1. Suicide Lethality: A Concept Analysis.

    Science.gov (United States)

    DeBastiani, Summer; De Santis, Joseph P

    2018-02-01

    Suicide is a significant health problem internationally. Those who complete suicide may have different behaviors and risk factors than those who attempt a non-fatal suicide. The purpose of this article is to analyze the concept of suicide lethality and propose a clear definition of the concept through the identification of antecedents, attributes, and consequences. A literature search for articles published in the English language between 1970 and 2016 was conducted using MEDLINE, the Cochrane Library, Pubmed, Psychlit, Ovid, PsycINFO, and Proquest. The bibliographies of all included studies were also reviewed to identify additional relevant citations. A concept analysis was conducted on the literature findings using six stages of Walker and Avant's method. The concept analysis differentiated between suicide, lethality, suicidal behavior, and suicide lethality. Presence of a suicide plan or a written suicide note was not found to be associated with the majority of completed suicides included in the definition of suicide lethality. There are a few scales that measure the lethality of a suicide attempt, but none that attempt to measure the concept of suicide lethality as described in this analysis. Clarifying the concept of suicide lethality encourages awareness of the possibility of different suicidal behaviors associated with different suicide outcomes and will inform the development of future nursing interventions. A clearer definition of the concept of suicide lethality will guide clinical practice, research, and policy development aimed at suicide prevention.

  2. A method for calculation of dose per unit concentration values for aquatic biota

    International Nuclear Information System (INIS)

    Batlle, J Vives i; Jones, S R; Gomez-Ros, J M

    2004-01-01

    A dose per unit concentration database has been generated for application to ecosystem assessments within the FASSET framework. Organisms are represented by ellipsoids of appropriate dimensions, and the proportion of radiation absorbed within the organisms is calculated using a numerical method implemented in a series of spreadsheet-based programs. Energy-dependent absorbed fraction functions have been derived for calculating the total dose per unit concentration of radionuclides present in biota or in the media they inhabit. All radionuclides and reference organism dimensions defined within FASSET for marine and freshwater ecosystems are included. The methodology has been validated against more complex dosimetric models and compared with human dosimetry based on ICRP 72. Ecosystem assessments for aquatic biota within the FASSET framework can now be performed simply, once radionuclide concentrations in target organisms are known, either directly or indirectly by deduction from radionuclide concentrations in the surrounding medium

  3. Experimental RBE values of high LET radiations at low doses and the implications for quality factor assignment

    International Nuclear Information System (INIS)

    Sinclair, W.K.

    1985-01-01

    RBE determinations of special relevance to the quality factor assigned for radiation protection purposes are those relating to the effects of special importance at low doses, namely carcinogenesis and mutagenesis. Measurements of RBE that enable the maximum value of RBE, namely RBEsub(M), to be determined at low doses require data points as low as 0.1 Gy or even 0.01 Gy or high LET radiation. Corresponding data points as low as 0.5 Gy to 0.25 Gy or less of low LET radiation are also needed. Relatively few such measurements have been made, but many more are available now than formerly. A review of recent RBEs for tumour induction, life shortening, transformation, cytogenetics and genetic endpoints, which updated an earlier review, indicates a broad range of results. The principle findings are that X rays are more effective than hard γ rays at low doses by a factor of about 2, and that fission neutrons, alpha particles and heavy ions may be 30-50 times more effective, on the average, (some endpoints give higher, some lower values) than hard γ rays. The data would seem to indicate that in order to provide approximately equal protection against the risks at low doses from all radiations, adjustments upward in the quality factors for high LET radiations need to be considered. (author)

  4. Effects of low dose irradiation on the K-value and hypoxanthine concentration of fish fillets

    International Nuclear Information System (INIS)

    Williams, D.J.; Mitchell, G.E.; Nottingham, S.M.; Jarrett, S.J.; Petroff, M.

    1993-01-01

    Fillets of five fish species were irradiated at 0, 1 and 3kGy to investigate whether the K-value test of freshness can be applied to irradiated fish. Following irradiation, the fillets were stored on ice and sampled regularly for K-value analysis. Hypoxanthine (Hx) and total nucleotide content were also determined on fillets of two species. K-values of irradiated fillets were generally lower than those of unirradiated controls. Hypoxanthine levels paralleled the K-value changes. These results indicated that quality standards based on K-values or Hx levels that have been set for unirradiated species cannot be directly applied to fish that has been irradiated. Total nucleotide content did not appear to be affected by irradiation

  5. Assessing absorbed dose heterogeneities for organ S-value calculation in mice

    International Nuclear Information System (INIS)

    Mauxion, T.; Villoing, D.; Marcatili, S.; Garcia, M.P.; Poirot, M.; Bardies, M.; Suhard, J.; Barbet, J.

    2015-01-01

    Full text of publication follows. Introduction and aim: S-values calculated according to the MIRD scheme strongly depend on the size of source/target regions and particle ranges (1). Several mean organ S-values were recently calculated for mice in the context of targeted radionuclide therapy and molecular imaging (2). However, the heterogeneity of energy deposition at the sub-organ level is seldom taken into account and the relevance of mean organ S-values is not systematically evaluated. This study aims at assessing spatial variations associated to mean S-values for small animals to estimate energy deposition heterogeneity at the sub-organ or voxel level. Materials and methods: a 29 g-mouse-model generated at high spatial sampling (200*200*200 μm 3 ) from the Moby software was used to calculate S-values for several radionuclides of interest (3). Monte Carlo simulations were performed with GATE (v6.2), in which specific corrections were implemented and validated to improve the accuracy of voxel energy-scoring. Mean S-values and standard deviations were calculated from 3D-voxel-based energy deposition maps for several source/target organ pairs. As the standard deviation associated to the mean S-value in a given target organ includes both spatial and statistical fluctuations, we simulated an increasing number of primary particles (typically from 10 6 to 10 10 ) to estimate the impact of relative statistical/spatial fluctuations for several source/target pairs. A spatial dispersion factor (HS-value for Heterogeneity of S-value) was obtained when the standard deviation converged to a stable value. Results: several HS-values calculated for source organs were significant in case of self-irradiation for all considered radionuclides, but remained very low as compared to values obtained for short and large source/target distances. For example, for 131 I sources located in the thyroid, S(thyroid - thyroid)=1.80*10 -9 Gy.Bq -1 .s -1 and HS(thyroid - thyroid)=3.09*10 -10 Gy

  6. Accuracy evaluation of the estimated absorbed dose to water calibration factor values

    International Nuclear Information System (INIS)

    Ooi, A.S.; Supian Samat; Dolah, M.T.; Taiman Kadni

    2001-01-01

    The purpose of the present work was to evaluate the accuracy of the estimated N D,W values, i.e. N D,W (Est), in comparison with the experimentally obtained N D,W values, i.e. N D,W (Exp). Two methods of evaluation were used. The first method was based on the calculated percentage deviations Δ% of N D,W (Est) from N D,W (Exp). The mean μ% and the standard error σ se % of Δ(%) were obtained. The N D,W Est) values were said to be accurate if the condition of μ% ± σ se % D,W (Exp) and N D,W (Est). In this method, the condition of u D,W (Est) values were to be accurate. the work described here used n=10 data pairs of [N D,W (Exp) ± Δ N D,W (Exp), N D,W (Est) ± Δ N D,W (Est)]. The data pairs were the values reported by IAEA (n=2), NPL (n=1) and SSDL Malaysia (n=7). For the first method, μ% ± σ se % D,W (Est) values was accurate. For the second method, only two u-statistics values (that used data pairs reported by the IAEA) met the requirement. The remainders of the eight u-statistics values (that used data pairs reported by NPL and SSDL) would not only met the requirement if their standard uncertainties of N D,W (Exp) and N D,W (Est) be taken to be equal to 2σ (n=3) and 3σ (n=5). The need to increase the standard uncertainties from 1σ to 2σ or 3σ implied that the standard uncertainties reported by NPL and SSDL were somehow smaller that the magnitude reported by the IAEA. Reasons for this were discussed. (Author)

  7. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Cantinha, Rebeca S.; Nakano, Eliana; Silva, Luanna R.S.

    2009-01-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of 60 Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD 50 obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  8. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Cantinha, Rebeca S.; Nakano, Eliana [Instituto Butantan, Sao Paulo, SP (Brazil). Lab. de Parasitologia], e-mail: rebecanuclear@gmail.com, e-mail: eliananakano@butantan.gov.br; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: sborrely@ipen.br; Amaral, Ademir; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR)], e-mail: amaral@ufpe.br; Silva, Luanna R.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia], e-mail: amdemelo@hotmail.com, e-mail: luannaribeiro_lua@hotmail.com

    2009-07-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of {sup 60}Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD{sub 50} obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  9. The Value of Evidence in the Decision-Making Process for Reimbursement of Pharmacogenetic Dosing of Warfarin.

    Science.gov (United States)

    Janzic, Andrej; Locatelli, Igor; Kos, Mitja

    2017-10-01

    After early clinical trials that evaluated pharmacogenetic (PG) algorithms, many healthcare payers were reluctant to cover this technology and, consequently, PG dosing of warfarin could not be translated into clinical practice. The aim of this study was to estimate the value of upgrading evidence relating to PG dosing of warfarin from the healthcare payer perspective. Randomized controlled trials (RCTs) that evaluated PG dosing of warfarin were identified through a systematic literature search, and their findings were combined by a cumulative meta-analysis. A health economic model was used to estimate economic outcomes and to calculate the expected value of perfect information (EVPI) as a measure of the value of clinical trials for decision makers. Nine RCTs were identified and included in our analysis. The estimated difference in the percentage of time in the therapeutic range was 5.6 percentage points in 2007, decreasing to 4.3 percentage points when all studies were included. At a reimbursement price of €160 per PG testing, the EVPI for the clinical benefit was estimated at €80 and €90 per patient in 2007 and 2014, respectively. A reduction in the price of PG testing to €40, which was observed in this period, resulted in an EVPI of €3 per patient. The estimated cumulative effect of PG dosing has remained similar since 2007, but additional evidence has contributed to a more precise estimation. While these variations should not affect the reimbursement decision, a large decline in the cost of PG testing in recent years calls for reconsideration.

  10. Enhanced lethal effect of combined ACNU with x-ray on cultured HeLaS3 cells

    International Nuclear Information System (INIS)

    Kanazawa, Haruyuki; Miyamoto, Tadaaki

    1983-01-01

    The combined effects of ACNU and X-irradiation on cultured HeLaS 3 cells were investigated. Pretreatment with either ACNU or X-ray induced a substantial reduction in shoulder width the D 0 value of the dose-response curve for the other agent, given later was unchanged. ACNU did not inhibit the recovery of sublethal damage (SLD) induced by X-ray when this treatment preceded the spilit-dose experiment. Our results indicate that some cell damage induced by each agent is transmissible to the progeny of the surviving cells and that the interaction of ACNU and X-irradiation was lethal to the cells. (author)

  11. Doses-effect regression equations for some growth indicators of rice plantules from CO60 irradiated seeds

    International Nuclear Information System (INIS)

    Lopez, R.C.; Gonzalez, L.M.; Garcia, D.

    1993-01-01

    In the present work, dose-effect regression equations for energy and percentage germination, size, root length and dry mass of plantules from which values of DL-50 middle lethal dose were calculated and likely or unlikely equivalencies among them were established

  12. Dose values at the ovaries for sagittal irradiation equipment in X-ray pictures using a standard phantom

    International Nuclear Information System (INIS)

    Kragh, P.

    1977-07-01

    The dose values at the ovaries are calculated systematically with a phantom corresponding in its shape and composition to the human anatomy. In order to limit computer time for the photon transport calculations according to the Monte-Carlo-method the simplified method of calculation is used which was first stated by Rosenstein. The dose at the ovaries is listed in tables for the respective X-ray exposure in a.p. or p.a. direction at the standard film sizes. In addition, the exposure area product of the useful radiation and the distances of a reference point to the central beam and to the edge of the radiation field must be known. (orig.) [de

  13. Impact of purity aluminum filters in the value of the half-value layer and the estimation of effective dose in patients

    International Nuclear Information System (INIS)

    Lima, Nathan Willig; Hoff, Gabriela

    2014-01-01

    The half-value layer test (HVL) is important in the context of conventional radiology, it is the only test that allow us to obtain information about the quality of the radiation beam. This work promotes a preliminary analysis of the influence of the composition of the aluminum filters used in determining the value of HVL considering a realistic geometry. Deterministic Calculations were compared and results calculated with the Monte Carlo method to do the analysis proposed. Six different aluminum alloys (with one percent of each impurity) marketed worldwide and pure aluminum are used as the basis for the realization of deterministic calculations and Monte Carlo simulation. Experimental arrangement in conventional radiology, a combination of tungsten track and aluminum filtration was used for three different peak voltages: (66 kVp, 81 kVp, 125 kVp). For determining HVL on mammography, were used three track combinations and filter (Molybdenum-Molybdenum, Molybdenum-Rhodium, Tungsten-Rhodium) for three different peak voltages (25 kVp, 30 kVp, 35 kVp). The spectrum used for deterministic calculations were taken from the Report No 78 of the Engineering Institute of Physics in Medicine, 1997. The results show that the composition of aluminum filters may impact significantly in the outcome of the HVL test and therefore the dose calculations that use it as a correction factor. In mammography, one percent impurities can result in variations showed about 20% of the HVL value

  14. Effects of DDE and PCB (Aroclor 1260) on experimentally poisoned little brown bats (Myotis lucifugus): Lethal brain concentrations

    Science.gov (United States)

    Clark, D.R.; Stafford, C.J.

    1981-01-01

    Adult female little brown bats (Myotis lucifugus) were collected in a church attic in North East, Cecil County, Md. Mealworms (Tenebrio molitor) containing organochlorine pollutants were fed to the bats as follows: 5 bats were dosed at 480 ppm DDE, 12 at 150 ppm DDE, 5 at 1000 ppm polychlorinated biphenyl (PCB; Aroclor 1260), and 12 at 15 ppm PCB. Seven other bats were fed untreated mealworms. The objective was to elevate brain levels of DDE and PCB to lethality and measure these concentrations. During 40 d of dosage, one DDE-dosed bat and two PCB-dosed bats died after exhibiting the prolonged tremor that characterizes organochlorine poisoning. After dosage, surviving bats were starved to elevate brain levels of toxicants, and three additional DDE-dosed bats had tremors before dying. The mean brain concentration of DDE diagnostic of death was estimated as 603 ppm, range 540-670 ppm. This mean is 16-18% higher than means for Mexican free-tailed bats (Tadarida brasiliensis) and common grackles (Quiscalus quiscula), and may indicate less sensitivity. Lethal brain concentrations of Aroclor 1260 were 1300 and 1500 ppm. Such values appear to be higher than values (Aroclor 1254) for brown-headed cowbirds (Molothrus ater). During starvation, DDE-dosed bats lost weight about 24% faster than controls. If smaller amounts of stored DDE cause increases in metabolic rates of nonfeeding bats, as during hibernation or migration, the result could be premature energy depletion and increased mortality.

  15. Modification of damage following low doses

    International Nuclear Information System (INIS)

    Braby, L.A.; Nelson, J.M.; Metting, N.F.

    1988-01-01

    At very low doses the damage-interaction mechanism is responsible for very little lethal or potentially lethal damage, and repair of the latter should essentially disappear. An alternative model suggests that potentially lethal damage is either repaired with a constant half time or misrepaired at a rate which is proportional to the square of the damage concentration. In this case, as the dose decreases, the probability of misrepair decreases faster than the probability of repair, and repair becomes a more pronounced feature of the cell response. Since the consequence of unrepaired damage is an important question in determining the effects of low doses of radiation delivered at low dose rates, we have attempted to determine which of these two types of models is consistent with the response of plateau-phase CHO cells. In the earlier experiments, there was no indication of repair after a 50-rad exposure with a 24-hour split dose or plating delay; in fact, immediate plating resulted in survival slightly above control and delayed plating in survival slightly below the control value

  16. Induction of dominant lethal mutations by alkylating agnets in germ-cells of the silkworm, Bombyx mori

    International Nuclear Information System (INIS)

    Murota, Tetsuo; Murakami, Akio.

    1977-01-01

    The comparison of the intensity of activity was made by measuring radiation equivalent chemical (REC) dose in the experiment of the induction of dominant lethal mutation, using the germ cells of pupae five days before the moths will be hatched. The alkylating agents employed in the experiment are methyl methanesulfonate (MMS), ethyl methanesulfonate (EMS), diethyl sulfate (DSC) and mitomycine-C (MC). X-ray irradiation was employed in order to indicate the capability of inducing mutation of the alkylating agents with the radiation equivalent chemical dose (REC dose). The dose-hatchability curves for the alkylating agents showed sigmoidal fashion as observed in X-ray, regardless of germ cells. The REC value at LD (50) was estimated by comparing the relative mutagenic capability of these chemicals. In sperm, EMS and DES with concentration of 1.0 x 10 -7 M/g showed the same lethality as about 2.3 kR and 0.6 kR of X-ray. However, no significant reduction of embryonic lethality after the treatment of pupae with MC (up to 2.1 x 10 -7 M/g) and MMS (up to 1.0 x 10 -6 M/g) was observed. As the results, the order of mutagenic effectiveness was as follows: EMS>DES>MMS approximately equal to MC. When oocytes in the mid-pupae were treated with MMS, EMS and MC with concentration of 1.0 x 10 -7 M/g, MMS and EMS showed the same effects as 12.8 kR and 0.6 kR. Surprisingly, MC showed the same lethality as 232.3 kR. This extremely high sensitivity of oocytes to MC may be ascribed to the inhibiting effect of the drug on the meiotic division. (Iwakiri, K.)

  17. Theories of Lethal Mutagenesis: From Error Catastrophe to Lethal Defection.

    Science.gov (United States)

    Tejero, Héctor; Montero, Francisco; Nuño, Juan Carlos

    2016-01-01

    RNA viruses get extinct in a process called lethal mutagenesis when subjected to an increase in their mutation rate, for instance, by the action of mutagenic drugs. Several approaches have been proposed to understand this phenomenon. The extinction of RNA viruses by increased mutational pressure was inspired by the concept of the error threshold. The now classic quasispecies model predicts the existence of a limit to the mutation rate beyond which the genetic information of the wild type could not be efficiently transmitted to the next generation. This limit was called the error threshold, and for mutation rates larger than this threshold, the quasispecies was said to enter into error catastrophe. This transition has been assumed to foster the extinction of the whole population. Alternative explanations of lethal mutagenesis have been proposed recently. In the first place, a distinction is made between the error threshold and the extinction threshold, the mutation rate beyond which a population gets extinct. Extinction is explained from the effect the mutation rate has, throughout the mutational load, on the reproductive ability of the whole population. Secondly, lethal defection takes also into account the effect of interactions within mutant spectra, which have been shown to be determinant for the understanding the extinction of RNA virus due to an augmented mutational pressure. Nonetheless, some relevant issues concerning lethal mutagenesis are not completely understood yet, as so survival of the flattest, i.e. the development of resistance to lethal mutagenesis by evolving towards mutationally more robust regions of sequence space, or sublethal mutagenesis, i.e., the increase of the mutation rate below the extinction threshold which may boost the adaptability of RNA virus, increasing their ability to develop resistance to drugs (including mutagens). A better design of antiviral therapies will still require an improvement of our knowledge about lethal

  18. CELLDOSE: A Monte Carlo code to assess electron dose distribution - S values for 131I in spheres of various sizes

    International Nuclear Information System (INIS)

    Champion, C.; Zanotti-Fregonara, P.; Hindie, E; Hindie, E.

    2008-01-01

    Monte Carlo simulation can be particularly suitable for modeling the microscopic distribution of energy received by normal tissues or cancer cells and for evaluating the relative merits of different radiopharmaceuticals. We used a new code, CELLDOSE, to assess electron dose for isolated spheres with radii varying from 2,500 μm down to 0.05 μm, in which 131 I is homogeneously distributed. Methods: All electron emissions of 131 I were considered,including the whole β - 131 I spectrum, 108 internal conversion electrons, and 21 Auger electrons. The Monte Carlo track-structure code used follows all electrons down to an energy threshold E-cutoff 7.4 eV. Results: Calculated S values were in good agreement with published analytic methods, lying in between reported results for all experimental points. Our S values were also close to other published data using a Monte Carlo code. Contrary to the latter published results, our results show that dose distribution inside spheres is not homogeneous, with the dose at the outmost layer being approximately half that at the center. The fraction of electron energy retained within the spheres decreased with decreasing radius (r): 87.1 % for r 2,500 μm, 8.73% for r 50 μm, and 1.18% for r 5 μm. Thus, a radioiodine concentration that delivers a dose of 100 Gy to a micro-metastasis of 2,500 μm radius would deliver 10 Gy in a cluster of 50 μm and only 1.4 Gy in an isolated cell. The specific contribution from Auger electrons varied from 0.25% for the largest sphere up to 76.8% for the smallest sphere. Conclusion: The dose to a tumor cell will depend on its position in a metastasis. For the treatment of very small metastases, 131 I may not be the isotope of choice. When trying to kill isolated cells or a small cluster of cells with 131 I, it is important to get the iodine as close as possible to the nucleus to get the enhancement factor from Auger electrons. The Monte Carlo code CELLDOSE can be used to assess the electron map deposit

  19. Lethal and mutagenic effects of ion beams and γ-rays in Aspergillus oryzae

    International Nuclear Information System (INIS)

    Toyoshima, Yoshiyuki; Takahashi, Akemi; Tanaka, Hisaki; Watanabe, Jun; Mogi, Yoshinobu; Yamazaki, Tatsuo; Hamada, Ryoko; Iwashita, Kazuhiro; Satoh, Katsuya; Narumi, Issay

    2012-01-01

    Highlights: ► We investigated the effects of different LET radiation in A. oryzae. ► Both γ-rays and ion beams induced base substitutions, frameshifts, deletions. ► Both γ-rays and ion beams induced genome-wide large-scale mutations in A. oryzae. ► Some differences in the types and frequencies of mutations were found. ► Our results provide new basic insights into the mutation breeding of A. oryzae. - Abstract: Aspergillus oryzae is a fungus that is used widely in traditional Japanese fermentation industries. In this study, the lethal and mutagenic effects of different linear energy transfer (LET) radiation in freeze-dried conidia of A. oryzae were investigated. The lethal effect, which was evaluated by a 90% lethal dose, was dependent on the LET value of the ionizing radiation. The most lethal ionizing radiation among that tested was 12 C 5+ ion beams with an LET of 121 keV/μm. The 12 C 5+ ion beams had a 3.6-times higher lethal effect than low-LET (0.2 keV/μm) γ-rays. The mutagenic effect was evaluated by the frequency of selenate resistant mutants. 12 C 6+ ion beams with an LET of 86 keV/μm were the most effective in inducing selenate resistance. The mutant frequency following exposure to 12 C 6+ ion beams increased with an increase in dose and reached 3.47 × 10 −3 at 700 Gy. In the dose range from 0 to 700 Gy, 12 C 5+ ion beams were the second most effective in inducing selenate resistance, the mutant frequency of which reached a maximum peak (1.67 × 10 −3 ) at 400 Gy. To elucidate the characteristics of mutation induced by ionizing radiation, mutations in the sulphate permease gene (sB) and ATP sulfurylase gene (sC) loci, the loss of function of which results in a selenate resistant phenotype, were compared between 12 C 5+ ion beams and γ-rays. We detected all types of transversions and transitions. For frameshifts, the frequency of a +1 frameshift was the highest in all cases. Although the incidence of deletions >2 bp was generally low

  20. Lethal and mutagenic effects of ion beams and γ-rays in Aspergillus oryzae.

    Science.gov (United States)

    Toyoshima, Yoshiyuki; Takahashi, Akemi; Tanaka, Hisaki; Watanabe, Jun; Mogi, Yoshinobu; Yamazaki, Tatsuo; Hamada, Ryoko; Iwashita, Kazuhiro; Satoh, Katsuya; Narumi, Issay

    2012-12-01

    Aspergillus oryzae is a fungus that is used widely in traditional Japanese fermentation industries. In this study, the lethal and mutagenic effects of different linear energy transfer (LET) radiation in freeze-dried conidia of A. oryzae were investigated. The lethal effect, which was evaluated by a 90% lethal dose, was dependent on the LET value of the ionizing radiation. The most lethal ionizing radiation among that tested was (12)C(5+) ion beams with an LET of 121keV/μm. The (12)C(5+) ion beams had a 3.6-times higher lethal effect than low-LET (0.2keV/μm) γ-rays. The mutagenic effect was evaluated by the frequency of selenate resistant mutants. (12)C(6+) ion beams with an LET of 86keV/μm were the most effective in inducing selenate resistance. The mutant frequency following exposure to (12)C(6+) ion beams increased with an increase in dose and reached 3.47×10(-3) at 700Gy. In the dose range from 0 to 700Gy, (12)C(5+) ion beams were the second most effective in inducing selenate resistance, the mutant frequency of which reached a maximum peak (1.67×10(-3)) at 400Gy. To elucidate the characteristics of mutation induced by ionizing radiation, mutations in the sulphate permease gene (sB) and ATP sulfurylase gene (sC) loci, the loss of function of which results in a selenate resistant phenotype, were compared between (12)C(5+) ion beams and γ-rays. We detected all types of transversions and transitions. For frameshifts, the frequency of a +1 frameshift was the highest in all cases. Although the incidence of deletions >2bp was generally low, deletions >20bp were characteristic for (12)C(5+) ion beams. γ-rays had a tendency to generate mutants carrying a multitude of mutations in the same locus. Both forms of radiation also induced genome-wide large-scale mutations including chromosome rearrangements and large deletions. These results provide new basic insights into the mutation breeding of A. oryzae using ionizing radiation. Crown Copyright © 2012. Published

  1. The impact of MCS models and EFAC values on the dose simulation for a proton pencil beam

    International Nuclear Information System (INIS)

    Chen, Shih-Kuan; Chiang, Bing-Hao; Lee, Chung-Chi; Tung, Chuan-Jong; Hong, Ji-Hong; Chao, Tsi-Chian

    2017-01-01

    The Multiple Coulomb Scattering (MCS) model plays an important role in accurate MC simulation, especially for small field applications. The Rossi model is used in MCNPX 2.7.0, and the Lewis model in Geant4.9.6.p02. These two models may generate very different angular and spatial distributions in small field proton dosimetry. Beside angular and spatial distributions, step size is also an important issue that causes path length effects. The Energy Fraction (EFAC) value can be used in MCNPX 2.7.0 to control step sizes of MCS. In this study, we use MCNPX 2.7.0, Geant4.9.6.p02, and one pencil beam algorithm to evaluate the effect of dose deposition because of different MCS models and different EFAC values in proton disequilibrium situation. Different MCS models agree well with each other under a proton equilibrium situation. Under proton disequilibrium situations, the MCNPX and Geant4 results, however, show a significant deviation (up to 43%). In addition, the path length effects are more significant when EFAC is equal to 0.917 and 0.94 in small field proton dosimetry, and using a 0.97 EFAC value is the best for both accuracy and efficiency - Highlights: • MCS and EFAC are important in accurate MC simulation for proton pencil beams. • Bragg curves of MCNPX and Geant4 have a dose deviation up to 43%. • Lateral profiles from MCNPX is wider than those from Geant4. • Large EFAC caused path length effect, but no effects on lateral profiles. • 0.97 EFAC value is the best for both accuracy and efficiency.

  2. Patterns of Lethality and Absorbed Dose Distributions in Mice for Monoenergetic Neutrons; Letalite et Distribution de la Dose Absorbee chez la Souris pour des Neutrons Monoenergetiques; Letal'nost' i raspredelenie pogloshchennoj dozy pri obluchenii myshej monoehnergeticheskimi neitronami; Letalidad y Distribucion de las Dosis Absorbidas por el Raton para Neutrones Monoenergeticos

    Energy Technology Data Exchange (ETDEWEB)

    Frigerio, N. A.; Jordan, D. L. [Argonne National Laboratory, Argonne, IL (United States)

    1964-03-15

    The presence of strong C, N and O resonances in the 100 to 1500 keV region has permitted the study of specific neutron-nuclide interactions as reflected in lethality, RBE maxima etc. Sixty-two {mu}A of resolved Van de Graaf protons, 1882 to 2738 keV, yielded monoenergetic neutrons via Li{sup 7}(p, n)Be{sup 7}. Virgin female CF-1 mice were exposed in celluloid capsules to the mono-energetic neutrons at distances of 3.1 to 11.3 cm from the source at laboratory angles of 0 to 1 radian. Mice were exposed bilaterally while simultaneously in motion through either circular or elliptical orbits normal to the axis of the beam. Thus, control of dose distribution within the animal was possible. Absolute flux measurements were made with U{sup 235} fission counters and by absolute counting of Au wires and foils activated within Cd covers. Patterns of dose absorption were measured with micro-ionization chambers and with a specially developed FeSO{sub 4}-NH{sub 4}SCN dosimeter of high sensitivity. Relative dose measurements were made with Hurst proton-recoil gas counters and B{sup 10} , Li{sup 6} and proton-recoil scintillators. Neutron-energy distributions were measured with specially developed B{sup 10}, He{sup 3} and Li{sup 6} gas and solid-state spectrometers. Gamma contributions were measured with Ne/Ar chamber counters. These measurements showed gamma contribution to be less than 0.8%, and thermal-epithermal less than 0.01%, of the total rad dose. Animals were exposed to median midpoint doses ranging from 180 to 1200 rad at neutron energies from 396 to 658 keV {+-} 50 keV to cover the region of N and O resonances. Levels and patterns of lethality proved to be strong functions of neutron energy and equally strong, but independent, functions of dose distribution. Regardless of dose, energy or distribution, however, all animals surviving five days survived at least 144 days, dying then of the usual long-term effects. This suggests that monoenergetic fast neutrons, free of

  3. An Improved Methodology of Monetary Values of the Unit Collective Dose for Intervention Against Long-Term Exposure Following a Nuclear Accident

    International Nuclear Information System (INIS)

    Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Choi, Young Gil; Han, Moon Hee

    2002-01-01

    A more practice approach for the determination of monetary values of the unit collective dose for intervention against long-term exposure following a nuclear accident was proposed. In addition, the monetary values of the unit collective dose estimated from the proposed approach were compared with those estimated from the previous model, which are derived from assumptions of routine exposure and the same values are applied in a nuclear accident without modification, using Korea economic data. The monetary values based on the proposed approach showed a distinct difference depending on inequity in the distribution of individual doses. The discounting rate was also an important factor in determination of monetary values of the unit collective dose

  4. An Improved Methodology of Monetary Values of the Unit Collective Dose for Intervention Against Long-Term Exposure Following a Nuclear Accident

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Choi, Young Gil; Han, Moon Hee [KAERI, Daejeon (Korea, Republic of)

    2002-06-15

    A more practice approach for the determination of monetary values of the unit collective dose for intervention against long-term exposure following a nuclear accident was proposed. In addition, the monetary values of the unit collective dose estimated from the proposed approach were compared with those estimated from the previous model, which are derived from assumptions of routine exposure and the same values are applied in a nuclear accident without modification, using Korea economic data. The monetary values based on the proposed approach showed a distinct difference depending on inequity in the distribution of individual doses. The discounting rate was also an important factor in determination of monetary values of the unit collective dose.

  5. Lethal and Sublethal Effects of Fenpropathrin on the Biological Performance of Scolothrips longicornis (Thysanoptera: Thripidae)

    DEFF Research Database (Denmark)

    Pakyari, Hajar; Enkegaard, Annie

    2013-01-01

    Determination of negative nontarget effects of pesticides on beneficial organisms by measuring only lethal effects is likely to underestimate effects of sublethal doses. In this study, the sublethal effects of fenpropathrin on the predatory thrips Scolothrips longicornis Priesner (Thysanoptera: T...

  6. ACCEPTABILITY EVALUATION FOR USING ICRP TISSUE WEIGHTING FACTORS TO CALCULATE EFFECTIVE DOSE VALUE FOR SEPARATE GENDER-AGE GROUPS OF RUSSIAN FEDERATION

    Directory of Open Access Journals (Sweden)

    L. V. Repin

    2013-01-01

    Full Text Available An article describes radiation risk factors for several gender-age population groups according to Russian statistical and medical-demographic data, evaluates the lethality rate for separate nosologic forms of malignant neoplasms based on Russian cancer registries according to the method of the International Agency for Cancer Research. Relative damage factors are calculated for the gender-age groups under consideration. The tissue weighting factors recommended by ICRP to calculate effective doses are compared with relative damage factors calculated by ICRP for the nominal population and with similar factors calculated in this work for separate population cohorts in theRussian Federation. The significance of differences and the feasibility of using tissue weighting factors adapted for the Russian population in assessing population risks in cohorts of different gender-age compositions have been assessed.

  7. Chronic exposure of corals to fine sediments: lethal and sub-lethal impacts.

    Directory of Open Access Journals (Sweden)

    Florita Flores

    Full Text Available Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata more than the upright branching species (Acropora millepora. The lowest sediment treatments that caused full colony mortality were 30 mg l(-1 TSS (25 mg cm(-2 day(-1 for M. aequituberculata and 100 mg l(-1 TSS (83 mg cm(-2 day(-1 for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue.

  8. Chronic Exposure of Corals to Fine Sediments: Lethal and Sub-Lethal Impacts

    Science.gov (United States)

    Flores, Florita; Hoogenboom, Mia O.; Smith, Luke D.; Cooper, Timothy F.; Abrego, David; Negri, Andrew P.

    2012-01-01

    Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS) for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata) more than the upright branching species (Acropora millepora). The lowest sediment treatments that caused full colony mortality were 30 mg l−1 TSS (25 mg cm−2 day−1) for M. aequituberculata and 100 mg l−1 TSS (83 mg cm−2 day−1) for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue. PMID:22662225

  9. Hematologic syndrome in man modeled from mammalian lethality

    International Nuclear Information System (INIS)

    Jones, T.D.

    1981-01-01

    Data on acute radiation lethality due to failure of the hematologic system in rats, mice, dogs, swine, monkeys and man are analyzed. Based on the available data, the mortality incidences for 1-100% levels can be computed directly if one has only an estimate of the dose lethal to 50% of the population (LD 50 ) for the mammalian strain and radiation environment of interest. The sole restriction is that the dose profile to the marrow be moderately uniform. If an LD 50 for any exposure situation has been measured, then one can readily scale to any desired situation through implicit-biological and empirical-physical relationships. The LD 50 for man, exposed to an isotropic cloud of photons, and knowledge of the bone-marrow dose profiles readily permit evaluation of the model for other levels of human mortality from different irradiating particles, partial body irradiation and spatially dependent and/or mixed radiation environments. (author)

  10. The ratio of ICRP103 to ICRP60 calculated effective doses from CT: Monte Carlo calculations with the ADELAIDE voxel paediatric model and comparisons with published values

    International Nuclear Information System (INIS)

    Caon, Martin

    2013-01-01

    The ADELAIDE voxel model of paediatric anatomy was used with the EGSnrc Monte Carlo code to compare effective dose from computed tomography (CT) calculated with both the ICRP103 and ICRP60 definitions which are different in their tissue weighting factors and in the included tissues. The new tissue weighting factors resulted in a lower effective dose for pelvis CT (than if calculated using ICRP60 tissue weighting factors), by 6.5 % but higher effective doses for all other examinations. ICRP103 calculated effective dose for CT abdomen + pelvis was higher by 4.6 %, for CT abdomen (by 9.5 %), for CT chest + abdomen + pelvis (by 6 %), for CT chest + abdomen (by 9.6 %), for CT chest (by 10.1 %) and for cardiac CT (by 11.5 %). These values, along with published values of effective dose from CT that were calculated for both sets of tissue weighting factors were used to determine single values for the ratio ICRP103:ICRP60 calculated effective doses from CT, for seven CT examinations. The following values for ICRP103:ICRP60 are suggested for use to convert ICRP60 calculated effective dose to ICRP103 calculated effective dose for the following CT examinations: Pelvis CT, 0.75; for abdomen CT, abdomen + pelvis CT, chest + abdomen + pelvis CT, 1.00; for chest + abdomen CT, and for chest CT. 1.15; for cardiac CT 1.25.

  11. Non-Lethal Weapons Program

    Science.gov (United States)

    Sheets Frequently Asked Questions Non-Lethal Weapons FAQs Active Denial System FAQs Human Electro -Muscular Incapacitation FAQs Related Links Business Opportunities Contact JNLWD Congressional Engagement , Wednesday, Sept 20, 2017. The Active Denial System, blunt-impact munitions, dazzling lasers, LRAD 100X

  12. Spectrum-to-dose conversion operator value function of a Ge(Li) in-situ environmental gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Terada, Hiromi; Sakai, Eiji; Katagiri, Masaki

    1976-05-01

    A spectrum-to-dose conversion operator value function was obtained for a 73cm 3 closed-end coaxial Ge(Li) in-situ environmental gamma-ray spectrometer; factors influencing the function are considered. (auth.)

  13. [Value of desmopressin stimulation test and high dose dexamethasone suppression testin the etiologic diagnosis of ACTH dependent Cushing's syndrome].

    Science.gov (United States)

    Zhang, Weiwei; Yu, Yerong; Tan, Huiwen; Wang, Chun; Li, Jianwei; An, Zhenmei; Liu, Yuping

    2016-03-22

    To investigate the value of desmopressin (DDAVP) stimulation test and high dose dexamethasone suppression test (HDDST) in establishing the cause of ACTH dependent Cushing's syndrome. The clinical data of patients with ACTH dependent Cushing's syndrome at West China Hospital from January 1, 2010 to September 30, 2015 was analyzed. The sensitivity and specificity of DDAVP stimulation test, HDDST, and the diagnostic accordance rate when the two tests were combined, were evaluated based on the diagnostic gold standard. A total of 85 patients with Cushing's disease and 10 patients with ectopic ACTH syndrome were included. The sensitivity and specificity of DDAVP stimulation test were 87% and 5/5, respectively, whereas those of HDDST were 79% and 8/10, respectively. The standard high dose dexamethasone suppression test showed a higher sensitivity than overnight 8 mg dexamethasone suppression test. When the two tests had consistent results, the diagnostic accordance rate was 100%. DDAVP stimulation test and HDDST are both efficient modalities for the diagnosis of Cushing's Disease and ectopic ACTH syndrome. The accuracy of diagnosis can be further improved by combining the two tests.

  14. Empirical complexities in the genetic foundations of lethal mutagenesis.

    Science.gov (United States)

    Bull, James J; Joyce, Paul; Gladstone, Eric; Molineux, Ian J

    2013-10-01

    From population genetics theory, elevating the mutation rate of a large population should progressively reduce average fitness. If the fitness decline is large enough, the population will go extinct in a process known as lethal mutagenesis. Lethal mutagenesis has been endorsed in the virology literature as a promising approach to viral treatment, and several in vitro studies have forced viral extinction with high doses of mutagenic drugs. Yet only one empirical study has tested the genetic models underlying lethal mutagenesis, and the theory failed on even a qualitative level. Here we provide a new level of analysis of lethal mutagenesis by developing and evaluating models specifically tailored to empirical systems that may be used to test the theory. We first quantify a bias in the estimation of a critical parameter and consider whether that bias underlies the previously observed lack of concordance between theory and experiment. We then consider a seemingly ideal protocol that avoids this bias-mutagenesis of virions-but find that it is hampered by other problems. Finally, results that reveal difficulties in the mere interpretation of mutations assayed from double-strand genomes are derived. Our analyses expose unanticipated complexities in testing the theory. Nevertheless, the previous failure of the theory to predict experimental outcomes appears to reside in evolutionary mechanisms neglected by the theory (e.g., beneficial mutations) rather than from a mismatch between the empirical setup and model assumptions. This interpretation raises the specter that naive attempts at lethal mutagenesis may augment adaptation rather than retard it.

  15. Effects of DDE on experimentally poisoned free-tailed bats (Tadarida brasiliensis): Lethal brain concentrations

    Science.gov (United States)

    Clark, D.R.; Kroll, J.C.

    1977-01-01

    Adult female free-tailed bats (Tadarida brasiliensis) were collected at Bracken Cave, Texas, and shipped to the Patuxent Wildlife Research Center. Treated mealworms (Tenebrio molitor) containing 107 ppm DDE were fed to 17 bats; five other bats were fed untreated mealworms. After 40 days on dosage, during which one dosed bat was killed accidentally, four dosed bats were frozen and the remaining 17 were starved to death. The objective was to elevate brain levels of DDE to lethality and measure these concentrations. After the feeding period, dosed bats weighed less than controls. After starvation, the body condition of dosed bats was poorer than that of controls even though there was no difference in the amounts of carcass fat. During starvation, dosed bats lost weight faster than controls. Also, four dosed bats exhibited the prolonged tremoring that characterizes DDE poisoning. DDE increased in brains of starving bats as fat was metabolized. The estimated mean brain concentration of DDE diagnostic of death was 519 ppm with a range of 458-564 ppm. These values resemble diagnostic levels known for two species of passerine birds, but they exceed published levels for two free-tailed bats from Carlsbad Caverns, New Mexico.

  16. Venous thromboembolism: Additional diagnostic value and radiation dose of pelvic CT venography in patients with suspected pulmonary embolism

    International Nuclear Information System (INIS)

    Reichert, Miriam; Henzler, Thomas; Krissak, Radko; Apfaltrer, Paul; Huck, Kurt; Buesing, Karen; Sueselbeck, Tim; Schoenberg, Stefan O.; Fink, Christian

    2011-01-01

    Purpose: To assess the additional diagnostic value of indirect CT venography (CTV) of the pelvis and upper thighs performed after pulmonary CT angiography (CTA) for the diagnosis of venous thromboembolism (VTE). Materials and methods: In a retrospective analysis, the radiology information system entries between January 2003 and December 2007 were searched for patients who received pulmonary CTA and additional CTV of the pelvis and upper thighs. Of those patients, the radiology reports were reviewed for the diagnosis of pulmonary embolism (PE) and deep venous thrombosis (DVT) in the pelvic veins and veins of the upper thighs. In cases with an isolated pelvic thrombosis at CTV (i.e. which only had a thrombosis in the pelvic veins but not in the veins of the upper thigh) ultrasound reports were reviewed for the presence of DVT of the legs. The estimated radiation dose was calculated for pulmonary CTA and for CTV of the pelvis. Results: In the defined period 3670 patients were referred to our institution for exclusion of PE. Of those, 642 patients (353 men, 289 women; mean age, 65 ± 15 years, age range 18-98 years) underwent combined pulmonary CTA and CTV. Among them, PE was found in 227 patients (35.4%). In patients without PE CTV was negative in all cases. In patients with PE, CTV demonstrated pelvic thrombosis in 24 patients (3.7%) and thrombosis of the upper thighs in 43 patients (6.6%). Of those patients 14 (2.1%) had DVT in the pelvis and upper thighs. In 10 patients (1.5%) CTV showed an isolated pelvic thrombosis. Of those patients ultrasound reports were available in 7 patients, which revealed DVT of the leg veins in 5 cases (1%). Thus, the estimated prevalence of isolated pelvic thrombosis detected only by pelvic CTV ranges between 1-5/642 patients (0.1-0.7%). Radiation dose ranges between 4.8 and 9.7 mSv for additional CTV of the pelvis. Conclusion: CTV of the pelvis performed after pulmonary CTA is of neglectable additional diagnostic value for the

  17. Gluconeogenesis in lethally X-irradiated rats

    International Nuclear Information System (INIS)

    Paulikova, E.; Ahlers, I.; Praslicka, M.

    1983-01-01

    The in vivo incorporation of U- 14 C-alanine into blood glucose and liver glycogen was measured in rats irradiated with a single whole body lethal dose of X-rays. Changes in gluconeogenic enzyme activities were studied in the liver. Increased incorporation of 14 C-alanine into blood glucose and liver glycogen were found after irradiation. Liver phosphoenolpyruvate carboxykinase and glycogenic activity underwent almost parallel changes and were significantly elevated from the 6th to the 48th hour, with resultant accumulation of glycogen. Glucose-6-phosphatase activity was depressed and there was a negative correlation between it and liver glycogen concentration. Maximum fructose-1,6-diphosphatase activity was found at 48 hours. The results show that glycogen accumulation in the liver and the raised blood glucose level in X-irradiated rats are based on raised gluconeogenesis. (author)

  18. Gluconeogenesis in lethally X-irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Paulikova, E.; Ahlers, I.; Praslicka, M. (Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie)

    1983-02-01

    The in vivo incorporation of U-/sup 14/C-alanine into blood glucose and liver glycogen was measured in rats irradiated with a single whole body lethal dose of X-rays. Changes in gluconeogenic enzyme activities were studied in the liver. Increased incorporation of /sup 14/C-alanine into blood glucose and liver glycogen were found after irradiation. Liver phosphoenolpyruvate carboxykinase and glycogenic activity underwent almost parallel changes and were significantly elevated from the 6th to the 48th hour, with resultant accumulation of glycogen. Glucose-6-phosphatase activity was depressed and there was a negative correlation between it and liver glycogen concentration. Maximum fructose-1,6-diphosphatase activity was found at 48 hours. The results show that glycogen accumulation in the liver and the raised blood glucose level in X-irradiated rats are based on raised gluconeogenesis.

  19. Lethal photosensitization of biofilm-grown bacteria

    Science.gov (United States)

    Wilson, Michael

    1997-12-01

    Antibacterial agents are increasingly being used for the prophylaxis and treatment of oral diseases. As these agents can be rendered ineffective by resistance development in the target organisms there is a need to develop alternative antimicrobial approaches. Light-activated antimicrobial agents release singlet oxygen and free radicals which can kill adjacent bacteria and a wide range of cariogenic and periodontopathogenic bacteria has been shown to be susceptible to such agents. In the oral cavity these organisms are present as biofilms (dental plaques) which are less susceptible to traditional antimicrobial agents than bacterial suspensions. The results of these studies have shown that biofilm-grown oral bacteria are also susceptible to lethal photosensitization although the light energy doses required are grater than those needed to kill the organisms when they are grown as aqueous suspensions.

  20. A multivariate model of stakeholder preference for lethal cat management.

    Science.gov (United States)

    Wald, Dara M; Jacobson, Susan K

    2014-01-01

    Identifying stakeholder beliefs and attitudes is critical for resolving management conflicts. Debate over outdoor cat management is often described as a conflict between two groups, environmental advocates and animal welfare advocates, but little is known about the variables predicting differences among these critical stakeholder groups. We administered a mail survey to randomly selected stakeholders representing both of these groups (n=1,596) in Florida, where contention over the management of outdoor cats has been widespread. We used a structural equation model to evaluate stakeholder intention to support non-lethal management. The cognitive hierarchy model predicted that values influenced beliefs, which predicted general and specific attitudes, which in turn, influenced behavioral intentions. We posited that specific attitudes would mediate the effect of general attitudes, beliefs, and values on management support. Model fit statistics suggested that the final model fit the data well (CFI=0.94, RMSEA=0.062). The final model explained 74% of the variance in management support, and positive attitudes toward lethal management (humaneness) had the largest direct effect on management support. Specific attitudes toward lethal management and general attitudes toward outdoor cats mediated the relationship between positive (pstakeholder intention to support non-lethal cat management. Our findings suggest that stakeholders can simultaneously perceive both positive and negative beliefs about outdoor cats, which influence attitudes toward and support for non-lethal management.

  1. Left ventricular function during lethal and sublethal endotoxemia in swine

    International Nuclear Information System (INIS)

    Goldfarb, R.D.; Nightingale, L.M.; Kish, P.; Weber, P.B.; Loegering, D.J.

    1986-01-01

    Previous studies suggested that after a median lethal dose (LD 50 ) of endotoxin, cardiac contractility was depressed in nonsurviving dogs. The canine cardiovascular system is unlike humans in that dogs have a hepatic vein sphincter that is susceptible to adrenergic stimulation capable of raising hepatic and splanchnic venous pressures. The authors retested the hypothesis that lethality after endotoxin administration is associated with cardiac contractile depression in pigs, because of the hepatic circulation in this species is similar to that of humans. They compared cardiac mechanical function of pigs administered a high dose (250 μg/kg) or a low dose (100 μg/kg) endotoxin by use of the slope of the end-systolic pressure-diameter relationship (ESPDR) as well as other measurements of cardiac performance. In all the pigs administered a high dose, ESPDR demonstrated a marked, time-dependent depression whereas we observed no significant ESPDR changes after low endotoxin doses. The other cardiodynamic variables were uninterpretable, due to the significant changes in heart rate, end-diastolic diameter (preload), and aortic diastolic pressure (afterload). Plasma myocardia depressant factor activity accumulated in all endotoxin-administered animals, tending to be greater in the high-dose group. In this group, both subendocardial blood flow and global function were depressed, whereas pigs administered the low dose endotoxin demonstrated slight, but nonsignificant, increases in flow and function. These observations indicate that myocardial contractile depression is associated with a lethal outcome to high doses of endotoxin. Myocardial perfusion was measured using radiolabeled microspheres infused into the left atria

  2. Lethal mechanisms in gastric volvulus.

    Science.gov (United States)

    Omond, Kimberley J; Byard, Roger W

    2017-01-01

    A 55-year-old wheelchair-bound woman with severe cerebral palsy was found at autopsy to have marked distention of the stomach due to a volvulus. The stomach was viable, and filled with air and fluid and had pushed the left dome of the diaphragm upwards causing marked compression of the left lung with a mediastinal shift to the right (including the heart). There was no evidence of gastric perforation, ischaemic necrosis or peritonitis. Removal of the organ block revealed marked kyphoscoliosis. Histology confirmed the viability of the stomach and biochemistry showed no dehydration. Death in cases of acute gastric volvulus usually occurs because of compromise of the gastric blood supply resulting in ischaemic necrosis with distention from swallowed air and fluid resulting in perforation with lethal peritonitis. Hypovolaemic shock may also occur. However, the current case demonstrates an alternative lethal mechanism, that of respiratory compromise due to marked thoracic organ compression.

  3. SU-F-I-01: Normalized Mean Glandular Dose Values for Dedicated Breast CT Using Realistic Breast-Shaped Phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, A [Department of Radiology, Biomedical Engineering Graduate Group, University of California Davis, Sacramento, CA (United States); Boone, J [Departments of Radiology and Biomedical Engineering, Biomedical Engeering Graduate Group, University of California Davis, Sacramento, CA (United States)

    2016-06-15

    Purpose: To estimate normalized mean glandular dose values for dedicated breast CT (DgN-CT) using breast CT-derived phantoms and compare to estimations using cylindrical phantoms. Methods: Segmented breast CT (bCT) volume data sets (N=219) were used to measure effective diameter profiles and were grouped into quintiles by volume. The profiles were averaged within each quintile to represent the range of breast sizes found clinically. These profiles were then used to generate five voxelized computational phantoms (V1, V2, V3, V4, V5 for the small to large phantom sizes, respectively), and loaded into the MCNP6 lattice geometry to simulate normalized mean glandular dose coefficients (DgN-CT) using the system specifications of the Doheny-prototype bCT scanner in our laboratory. The DgN-CT coefficients derived from the bCT-derived breast-shaped phantoms were compared to those generated using a simpler cylindrical phantom using a constant volume, and the following constraints: (1) Length=1.5*radius; (2) radius determined at chest wall (Rcw), and (3) radius determined at the phantom center-of-mass (Rcm). Results: The change in Dg-NCT coefficients averaged across all phantom sizes, was - 0.5%, 19.8%, and 1.3%, for constraints 1–3, respectively. This suggests that the cylindrical assumption is a good approximation if the radius is taken at the breast center-of-mass, but using the radius at the chest wall results in an underestimation of the glandular dose. Conclusion: The DgN-CT coefficients for bCT-derived phantoms were compared against the assumption of a cylindrical phantom and proved to be essentially equivalent when the cylinder radius was set to r=1.5/L or Rcm. While this suggests that for dosimetry applications a patient’s breast can be approximated as a cylinder (if the correct radius is applied), this assumes a homogenous composition of breast tissue and the results may be different if the realistic heterogeneous distribution of glandular tissue is considered

  4. Lethality of gamma radiation and malathion to the indian meal moth, plodia interpunctella

    International Nuclear Information System (INIS)

    Eesa, N.M.; Moursy, L.E.

    1991-01-01

    The lethality of gamma radiation and the organo phosphorous insecticide, malathion, as well as the combined action of both was determined for the five larval instars of the indian meal moth, plodia interpunctella (Hubner). The younger instars were more susceptible to both gamma radiation and malathion. The L D 50 values of gamma radiation increased gradually with the instar. Malathion was highly toxic to the first four instars, but the fifth instar required a much larger dose. Gamma radiation combined with malathion at the L D 25 values was antagonistic when evaluated against each of the five larval instars of the indian meal moth. Thus, the use of gamma radiation with malathion does not seem to be a promising control strategy. However, further research investigations are needed to confirm this finding.3 tab

  5. Analysis of time of death of prenatally lethal Steeloid mutations

    International Nuclear Information System (INIS)

    Rinchik, E.M.; Cummings, C.C.; Bangham, J.W.; Hunsicker, P.R.; Phipps, E.L.; Stelzner, K.F.

    1987-01-01

    Deletion mutations have been extremely useful in initiating the functional and molecular dissections of regions of the mouse genome. For the d-se and c regions, for example, it was observed that radiation mutations carrying lethal factors separable, by complementation analysis, from the primary d, se, or c mutation itself, could often be associated at both the genetic and molecular levels with multilocus chromosomal deletions. Since many of the Oak Ridge Sld mutations arose in radiation mutagenesis experiments, a substantial number may carry chromosomal deletions that involve the Sl locus in chromosome 10. Because of the great value of deletion mutations for the genetic and molecular analysis of chromosomal regions and complex genetic loci, they have initiated a series of experiments designed to test whether radiation-induced Sld mutations carry other lethal factors, in addition to the lethality caused by severe alleles of the Sl locus itself, as one prescreen for identifying Sld's that are caused by deletions

  6. Influence of length of interval between pulses in PDR brachytherapy (PDRBT on value of Biologically Equivalent Dose (BED in healthy tissues

    Directory of Open Access Journals (Sweden)

    Tomasz Piotrowski

    2010-07-01

    Full Text Available Purpose: Different PDR treatment schemas are used in clinical practice, however optimal length of interval between pulses still remains unclear. The aim of this work was to compare value of BED doses measured in surrounded healthy tissues according to different intervals between pulses in PDRBT. Influence of doses optimization on BED values was analyzed.Material and methods: Fifty-one patients treated in Greater Poland Cancer Centre were qualified for calculations.Calculations of doses were made in 51 patients with head and neck cancer, brain tumor, breast cancer, sarcoma, penis cancer and rectal cancer. Doses were calculated with the use of PLATO planning system in chosen critical points in surrounded healthy tissues. For all treatment plans the doses were compared using Biologically Equivalent Dose formula.Three interval lengths (1, 2 and 4 hours between pulses were chosen for calculations. For statistical analysis Friedman ANOVA test and Kendall ratio were used.Results: The median value of BED in chosen critical points in healthy tissues was statistically related to the length of interval between PDR pulses and decreased exponentially with 1 hour interval to 4 hours (Kendall = from 0.48 to 1.0; p = from 0.002 to 0.00001.Conclusions: Prolongation of intervals between pulses in PDR brachytherapy was connected with lower values of BED doses in healthy tissues. It seems that longer intervals between pulses reduced the risk of late complications, but also decreased the tumour control. Furthermore, optimization influenced the increase of doses in healthy tissues.

  7. Pedigree analyses of yeast cells recovering from DNA damage allow assignment of lethal events to individual post-treatment generations

    International Nuclear Information System (INIS)

    Klein, F.; Karwan, A.; Wintersberger, U.

    1990-01-01

    Haploid cells of Saccharomyces cerevisiae were treated with different DNA damaging agents at various doses. A study of the progeny of individual such cells allowed the assignment of lethal events to distinct post treatment generations. By microscopically inspecting those cells which were not able to form visible colonies the authors could discriminate between cells dying from immediately effective lethal hits and those generating microcolonies probably as a consequence of lethal mutation(s). The experimentally obtained numbers of lethal events were mathematically transformed into mean probabilities of lethal fixations at taking place in cells of certain post treatment generations. Such analyses give detailed insight into the kinetics of lethality as a consequence of different kinds of DNA damage. For example, X-irradiated cells lost viability mainly by lethal hits, only at a higher dose also lethal mutations fixed in the cells that were in direct contact with the mutagen, but not in later generations, occurred. Ethyl methanesulfonate (EMS)-treated cells were hit by 00-fixations in a dose dependent manner. The distribution of all sorts of lethal fixations taken together, which occurred in the EMS-damaged cell families, was not random. For comparison analyses of cells treated with methyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine and nitrous acid are also reported

  8. A study to determine the differences between the displayed dose values for two full-field digital mammography units and values calculated using a range of Monte-Carlo-based techniques: A phantom study

    International Nuclear Information System (INIS)

    Borg, M.; Badr, I.; Royle, G. J.

    2013-01-01

    Modern full-field digital mammography (FFDM) units display the mean glandular dose (MGD) and the entrance or incident air kerma (K) to the breast following each exposure. Information on how these values are calculated is limited and knowing how displayed MGD values compare and correlate to conventional Monte-Carlo-based methods is useful. From measurements done on polymethyl methacrylate (PMMA) phantoms, it has been shown that displayed and calculated MGD values are similar for thin to medium thicknesses and appear to differ with larger PMMA thicknesses. As a result, a multiple linear regression analysis on the data was performed to generate models by which displayed MGD values on the two FFDM units included in the study may be converted to the Monte-Carlo values calculated by conventional methods. These models should be a useful tool for medical physicists requiring MGD data from FFDM units included in this paper and should reduce the survey time spent on dose calculations. (authors)

  9. Lethality of Rendang packaged in multilayer retortable pouch with sterilization process

    Science.gov (United States)

    Praharasti, A. S.; Kusumaningrum, A.; Frediansyah, A.; Nurhikmat, A.; Khasanah, Y.; Suprapedi

    2017-01-01

    Retort Pouch had become a choice to preserve foods nowadays, besides the used of the can. Both had their own advantages, and Retort Pouch became more popular for the reason of cheaper and easier to recycle. General Method usually used to estimate the lethality of commercial heat sterilization process. Lethality value wa s used for evaluating the efficacy of the thermal process. This study aimed to find whether different layers of pouch materials affect the lethality value and to find differences lethality in two types of multilayer retort pouch, PET/Aluminum Foil/Nylon/RCPP and PET/Nylon/Modified Aluminum/CPP. The result showed that the different layer arrangement was resulted different Sterilization Value (SV). PET/Nylon/Modified Aluminum/CPP had better heat penetration, implied by the higher value of lethality. PET/Nylon/Modified Aluminum/CPP had the lethality value of 6,24 minutes, whereas the lethality value of PET/Aluminum Foil/Nylon/RCPP was 3,54 minutes.

  10. Acute and sub-lethal response to mercury in Arctic and boreal calanoid copepods.

    Science.gov (United States)

    Overjordet, Ida Beathe; Altin, Dag; Berg, Torunn; Jenssen, Bjørn Munro; Gabrielsen, Geir Wing; Hansen, Bjørn Henrik

    2014-10-01

    Acute lethal toxicity, expressed as LC50 values, is a widely used parameter in risk assessment of chemicals, and has been proposed as a tool to assess differences in species sensitivities to chemicals between climatic regions. Arctic Calanus glacialis and boreal Calanus finmarchicus were exposed to mercury (Hg(2+)) under natural environmental conditions including sea temperatures of 2° and 10°C, respectively. Acute lethal toxicity (96 h LC50) and sub-lethal molecular response (GST expression; in this article gene expression is used as a synonym of gene transcription, although it is acknowledged that gene expression is also regulated, e.g., at translation and protein stability level) were studied. The acute lethal toxicity was monitored for 96 h using seven different Hg concentrations. The sub-lethal experiment was set up on the basis of nominal LC50 values for each species using concentrations equivalent to 50, 5 and 0.5% of their 96 h LC50 value. No significant differences were found in acute lethal toxicity between the two species. The sub-lethal molecular response revealed large differences both in response time and the fold induction of GST, where the Arctic species responded both faster and with higher mRNA levels of GST after 48 h exposure. Under the natural exposure conditions applied in the present study, the Arctic species C. glacialis may potentially be more susceptible to mercury exposure on the sub-lethal level. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Estimating patient dose from CT exams that use automatic exposure control: Development and validation of methods to accurately estimate tube current values.

    Science.gov (United States)

    McMillan, Kyle; Bostani, Maryam; Cagnon, Christopher H; Yu, Lifeng; Leng, Shuai; McCollough, Cynthia H; McNitt-Gray, Michael F

    2017-08-01

    The vast majority of body CT exams are performed with automatic exposure control (AEC), which adapts the mean tube current to the patient size and modulates the tube current either angularly, longitudinally or both. However, most radiation dose estimation tools are based on fixed tube current scans. Accurate estimates of patient dose from AEC scans require knowledge of the tube current values, which is usually unavailable. The purpose of this work was to develop and validate methods to accurately estimate the tube current values prescribed by one manufacturer's AEC system to enable accurate estimates of patient dose. Methods were developed that took into account available patient attenuation information, user selected image quality reference parameters and x-ray system limits to estimate tube current values for patient scans. Methods consistent with AAPM Report 220 were developed that used patient attenuation data that were: (a) supplied by the manufacturer in the CT localizer radiograph and (b) based on a simulated CT localizer radiograph derived from image data. For comparison, actual tube current values were extracted from the projection data of each patient. Validation of each approach was based on data collected from 40 pediatric and adult patients who received clinically indicated chest (n = 20) and abdomen/pelvis (n = 20) scans on a 64 slice multidetector row CT (Sensation 64, Siemens Healthcare, Forchheim, Germany). For each patient dataset, the following were collected with Institutional Review Board (IRB) approval: (a) projection data containing actual tube current values at each projection view, (b) CT localizer radiograph (topogram) and (c) reconstructed image data. Tube current values were estimated based on the actual topogram (actual-topo) as well as the simulated topogram based on image data (sim-topo). Each of these was compared to the actual tube current values from the patient scan. In addition, to assess the accuracy of each method in estimating

  12. Implications of tissue target-cell survival-curve shape for values of split-dose recovery doses: late versus early effects

    International Nuclear Information System (INIS)

    Redpath, J.L.; Peel, D.M.; Hopewell, J.W.

    1984-01-01

    Recent data from this laboratory on split-dose recovery for early and late effects in pig skin are consistent with the linear-quadratic model for cell survival, and with relative cell survival-curve shapes for early- and late-effect target cells where the early-effect cells have an intially steeper and straighter survival-curve than the late-effect cells. (author)

  13. UV-induced lethal sectoring and pure mutant clones in yeast.

    Science.gov (United States)

    Hannan, M A; Duck, P; Nasim, A

    1976-08-01

    The induction of lethal sectoring and pure mutant clones by ultraviolet light has been studied in a homogeneous G1 population of Saccharomyces cerevisiae grown in a normal growth medium. At the lowest UV dose of 250 ergs, which corresponds to a shoulder in the survival curve, all mutants appeared as pure clones. At higher doses the frequency of mosaic mutants progressively increased. These results indicate a relationship between the highest frequency of complete mutants and the maximum repair activity. In addition, the frequency of lethal sectoring at all doses tested was too low to account for the origin of pure mutant clones.

  14. Electroshock weapons can be lethal!

    Science.gov (United States)

    Lundquist, Marjorie

    2008-03-01

    Electroshock weapons (EWs)-stun guns, tasers, riot shields-are electroconductive devices designed to safely incapacitate healthy men neuromuscularly, so they are called nonlethal or less-lethal. EW firms seeking large nonmilitary markets targeted law enforcement and corrections personnel, who began using EWs in prisons/jails and on public patrol in 1980 in the USA. This shifted the EW-shocked population from healthy soldiers to a heterogeneous mix of both sexes, ages 6-92, in a wide variety of health conditions! An EW operates by disrupting normal physiological processes, producing transient effects in healthy people. But if a person's health is sufficiently compromised, the margin of safety can be lost, resulting in death or permanent health problems. 325 people have died after EW shock since 1980. Did the EW cause these deaths? Evidence indicates that EWs do play a causal role in most such deaths. EWs can be lethal for people in diabetic shock^1 (hypoglycemia), which may be why Robert Dziekanski-a Polish immigrant to Canada-died so quickly after he was tasered at Vancouver Airport: not having eaten for over 10 hours, he likely was severely hypoglycemic. The EW death rate in North America is 30 times higher than need be, because EW users have not been properly trained to use EWs on a heterogeneous population safely! ^1J. Clinical Engineering 30(3):111(2005).

  15. Acute and sub-lethal exposure to copper oxide nanoparticles causes oxidative stress and teratogenicity in zebrafish embryos.

    Science.gov (United States)

    Ganesan, Santhanamari; Anaimalai Thirumurthi, Naveenkumar; Raghunath, Azhwar; Vijayakumar, Savitha; Perumal, Ekambaram

    2016-04-01

    Nano-copper oxides are a versatile inorganic material. As a result of their versatility, the immense applications and usage end up in the environment causing a concern for the lifespan of various beings. The ambiguities surround globally on the toxic effects of copper oxide nanoparticles (CuO-NPs). Hence, the present study endeavored to study the sub-lethal acute exposure effects on the developing zebrafish embryos. The 48 hpf LC50 value was about 64 ppm. Therefore, we have chosen the sub-lethal dose of 40 and 60 ppm for the study. Accumulation of CuO-NPs was evidenced from the SEM-EDS and AAS analyzes. The alterations in the AChE and Na(+)/K(+)-ATPase activities disrupted the development process. An increment in the levels of oxidants with a concomitant decrease in the antioxidant enzymes confirmed the induction of oxidative stress. Oxidative stress triggered apoptosis in the exposed embryos. Developmental anomalies were observed with CuO-NPs exposure in addition to oxidative stress in the developing embryos. Decreased heart rate and hatching delay hindered the normal developmental processes. Our work has offered valuable data on the connection between oxidative stress and teratogenicity leading to lethality caused by CuO-NPs. A further molecular mechanism unraveling the uncharted connection between oxidative stress and teratogenicity will aid in the safe use of CuO-NPs. Copyright © 2015 John Wiley & Sons, Ltd.

  16. Impact of radiation dose and standardized uptake value of (18)FDG PET on nodal control in locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Ramlov, Anne; Kroon, Petra S; Jürgenliemk-Schulz, Ina M

    2015-01-01

    BACKGROUND: Despite local control now exceeding 90% with image-guided adaptive brachytherapy (IGABT), regional and distant metastases continue to curb survival in locally advanced cervical cancer. As regional lymph nodes often represent first site of metastatic spread, improved nodal control could...... improve survival. The aim of this study was to examine optimal volume and dose of external beam radiotherapy (EBRT) to maximize regional control including dose contribution from IGABT. MATERIAL AND METHODS: In total 139 patients from the EMBRACE study were analyzed. Individual nodal dose was determined...

  17. Rifaximin diminishes neutropenia following potentially lethal whole-body radiation.

    Science.gov (United States)

    Jahraus, Christopher D; Schemera, Bettina; Rynders, Patricia; Ramos, Melissa; Powell, Charles; Faircloth, John; Brawner, William R

    2010-07-01

    Terrorist attacks involving radiological or nuclear weapons are a substantial geopolitical concern, given that large populations could be exposed to potentially lethal doses of radiation. Because of this, evaluating potential countermeasures against radiation-induced mortality is critical. Gut microflora are the most common source of systemic infection following exposure to lethal doses of whole-body radiation, suggesting that prophylactic antibiotic therapy may reduce mortality after radiation exposure. The chemical stability, easy administration and favorable tolerability profile of the non-systemic antibiotic, rifaximin, make it an ideal potential candidate for use as a countermeasure. This study evaluated the use of rifaximin as a countermeasure against low-to-intermediate-dose whole-body radiation in rodents. Female Wistar rats (8 weeks old) were irradiated with 550 cGy to the whole body and were evaluated for 30 d. Animals received methylcellulose, neomycin (179 mg/kg/d) or variably dosed rifaximin (150-2000 mg/kg/d) one hour after irradiation and daily throughout the study period. Clinical assessments (e.g. body weight) were made daily. On postirradiation day 30, blood samples were collected and a complete blood cell count was performed. Animals receiving high doses of rifaximin (i.e. 1000 or 2000 mg/kg/d) had a greater increase in weight from the day of irradiation to postirradiation day 30 compared with animals that received placebo or neomycin. For animals with an increase in average body weight from irradiation day within 80-110% of the group average, methylcellulose rendered an absolute neutrophil count (ANC) of 211, neomycin rendered an ANC of 334, rifaximin 300 mg/kg/d rendered an ANC of 582 and rifaximin 1000 mg/kg/d rendered an ANC of 854 (P = 0.05 for group comparison). Exposure to rifaximin after near-lethal whole-body radiation resulted in diminished levels of neutropenia.

  18. Plasma microRNA profiles distinguish lethal injury in acetaminophen toxicity: A research study

    Institute of Scientific and Technical Information of China (English)

    Jeanine Ward; Shashi Bala; Jan Petrasek; Gyongyi Szabo

    2012-01-01

    AIM:To investigate plasma microRNA (miRNA) profiles indicative of hepatotoxicity in the setting of lethal acetaminophen (APAP) toxicity in mice.METHODS:Using plasma from APAP poisoned mice,either lethally (500 mg/kg) or sublethally (150 mg/kg) dosed,we screened commercially available murine microRNA libraries (SABiosciences,Qiagen Sciences,MD) to evaluate for unique miRNA profiles between these two dosing parameters.RESULTS:We distinguished numerous,unique plasma miRNAs both up- and downregulated in lethally compared to sublethally dosed mice.Of note,many of the greatest up- and downregulated miRNAs,namely 574-5p,466g,466f-3p,375,29c,and 148a,have been shown to be associated with asthma in prior studies.Interestingly,a relationship between APAP and asthma has been previously well described in the literature,with an as yet unknown mechanism of pathology.There was a statistically significant increase in alanine aminotransferase levels in the lethal compared to sublethal APAP dosing groups at the 12 h time point (P <0.001).There was 90% mortality in the lethally compared to sublethally dosed mice at the 48 h time point (P =0.011).CONCLUSION:We identified unique plasma miRNAs both up- and downregulated in APAP poisoning which are correlated to asthma development.

  19. Influence of temperature and pressure on the lethality of ultrasound

    International Nuclear Information System (INIS)

    Raso, J.; Pagan, R.; Condon, S.; Sala, F.J.

    1998-01-01

    A specially designed resistometer was constructed, and the lethal effect on Yersinia enterocolitica of ultrasonic waves (UW) at different static pressures (manosonication [MS]) and of combined heat-UW under pressure treatments (manothermosonication [MTS]) was investigated. During MS treatments at 30 degrees C and 200 kPa, the increase in the amplitude of UW of 20 kHz from 21 to 150 micrometers exponentially decreased decimal reduction time values (D(MS)) from 4 to 0.37 min. When pressure was increased from 0 to 600 kPa at a constant amplitude (150 micrometers) and temperature (30 degrees C), D(MS) values decreased from 1.52 to 0.20 min. The magnitude of this decrease in D(MS) declined progressively as pressure was increased. The influence of pressure on D(MS) values was greater with increased amplitude of UW. Pressure alone of as much as 600 kPa did not influence the heat resistance of Y. enterocolitica (D60 = 0.094; zeta = 5.65). At temperatures of as much as 58 degrees C, the lethality of UW under pressure was greater than that of heat treatment alone at the same temperature. At higher temperatures, this difference disappeared. Heat and UW under pressure seemed to act independently. The lethality of MTS treatments appeared to result from the added effects of UW under pressure and the lethal effect of heat. The individual contributions of heat and of UW under pressure to the total lethal effect of MTS depended on temperature. The inactivating effect of UW was not due to titanium particles eroded from the sonication horn. The addition to the MS media of cysteamine did not increase the resistance of Y. enterocolitica to MS treatment. MS treatment caused cell disruption

  20. RBE of Cf-252 neutrons as determined by its lethal, mutagenic, and cytogenetic effects on human cells

    International Nuclear Information System (INIS)

    Ban, Sadayuki

    1989-01-01

    To assess the biological effects of neutrons, a man-made spontaneously fissioning isotope, Cf-252, is useful as an experimental model to obtain basic biological data on mixed radiation of gamma-rays and neutrons. The paper describes the lethal effect of Cf-252 radiation on human skin fibroblasts, its lethal and mutagenic effect on HeLa MR cells, and the micronuclei inducing effect on human peripheral lymphocytes. Dose-survival responses of three fibroblast cell strains exposed to Cf-252 radiation are measured. Individual difference is larger than the experimental fluctuation. D 10 values of each strain are obtained from the linear model and linear-quadratic model. Though the dose rate of X-ray is higher than that of Cf-252 radiations, the mean value of RBE(n+γ) is simply obtained as 1.86+0.31 (RBE:relative biological effectiveness). RBE(n) of Cf-252 neutrons to high-dose-rate X-rays is 2.29. After X-ray irradiation, the survival curve of HeLa MR cells gives an extrapolation number of 3.6. It is 1.3 after Cf-252 irradiation. At 50% survival, RBE(n+γ) and RBE(n) are 2.05 and 2.6, respectively. At 10% survival they are 2.05 and 2.6. The mutation frequencies after X-ray irradiation showed a significant non-linear increase with dose. Those after Cf-252 irradiation increase linearly with dose. (N.K.)

  1. The additional value of first pass myocardial perfusion imaging during peak dose of dobutamine stress cardiac MRI for the detection of myocardial ischemia

    NARCIS (Netherlands)

    Lubbers, Daniel D.; Janssen, Caroline H. C.; Kuijpers, Dirkjan; Van Dijkman, Paul R. M.; Overbosch, Jelle; Willems, Tineke P.; Oudkerk, Matthijs

    Purpose of this study was to assess the additional value of first pass myocardial perfusion imaging during peak dose of dobutamine stress Cardiac-MR (CMR). Dobutamine Stress CMR was performed in 115 patients with an inconclusive diagnosis of myocardial ischemia on a 1.5 T system (Magnetom Avanto,

  2. Thermally assisted OSL application for equivalent dose estimation; comparison of multiple equivalent dose values as well as saturation levels determined by luminescence and ESR techniques for a sedimentary sample collected from a fault gouge

    Energy Technology Data Exchange (ETDEWEB)

    Şahiner, Eren, E-mail: sahiner@ankara.edu.tr; Meriç, Niyazi, E-mail: meric@ankara.edu.tr; Polymeris, George S., E-mail: gspolymeris@ankara.edu.tr

    2017-02-01

    Highlights: • Multiple equivalent dose estimations were carried out. • Additive ESR and regenerative luminescence were applied. • Preliminary SAR results employing TA-OSL signal were discussed. • Saturation levels of ESR and luminescence were investigated. • IRSL{sub 175} and SAR TA-OSL stand as very promising for large doses. - Abstract: Equivalent dose estimation (D{sub e}) constitutes the most important part of either trap-charge dating techniques or dosimetry applications. In the present work, multiple, independent equivalent dose estimation approaches were adopted, using both luminescence and ESR techniques; two different minerals were studied, namely quartz as well as feldspathic polymineral samples. The work is divided into three independent parts, depending on the type of signal employed. Firstly, different D{sub e} estimation approaches were carried out on both polymineral and contaminated quartz, using single aliquot regenerative dose protocols employing conventional OSL and IRSL signals, acquired at different temperatures. Secondly, ESR equivalent dose estimations using the additive dose procedure both at room temperature and at 90 K were discussed. Lastly, for the first time in the literature, a single aliquot regenerative protocol employing a thermally assisted OSL signal originating from Very Deep Traps was applied for natural minerals. Rejection criteria such as recycling and recovery ratios are also presented. The SAR protocol, whenever applied, provided with compatible D{sub e} estimations with great accuracy, independent on either the type of mineral or the stimulation temperature. Low temperature ESR signals resulting from Al and Ti centers indicate very large D{sub e} values due to bleaching in-ability, associated with large uncertainty values. Additionally, dose saturation of different approaches was investigated. For the signal arising from Very Deep Traps in quartz saturation is extended almost by one order of magnitude. It is

  3. Interpretation of proton relative biological effectiveness using lesion induction, lesion repair, and cellular dose distribution

    International Nuclear Information System (INIS)

    Paganetti, H.

    2005-01-01

    Phenomenological biophysical models have been successfully used to estimate the relative biological effectiveness (RBE) of ions. The predictive power of these models is limited because they require measured dose-response data that are not necessarily available for all clinically relevant end points. Furthermore, input parameters often lack mechanistic interpretation. In order to link RBE to more fundamental biological parameters we combine the concepts of two well-established biophysical models, i.e., the phenomenological 'track structure' model and the more mechanistic 'lethal lesion/potentially lethal lesion' (LPL) model. We parametrize a relation between RBE, dose homogeneity in the cell nucleus and induction rates for different lesion types. The macroscopic dose-response relationship is described in the LPL model and the microscopic, subcellular, relationship is determined by the local dose deposition pattern. The formalism provides a framework for a mechanistic interpretation of RBE values

  4. Effect of lethal and sub-lethal concentrations of tobacco (Nicotiana ...

    African Journals Online (AJOL)

    Lethal and sub-lethal bioassays on Clarias gariepinus were conducted to evaluate the toxicity of tobacco (Nicotiana tobaccum) leaf dust on weight gain and haematological indices of Clarias gariepinus (mean weight 10.5±0.70g) in glass aquaria with aeration system. The concentrations used during the lethal exposure are: ...

  5. Value of low-dose 2 X 2 Gy palliative radiotherapy in advanced low-grade non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Ng, M.; Wirth, A.; Ryan, G.; MacManus, M.

    2006-01-01

    Low-dose radiotherapy over the last decade has been reported to provide effective palliation for patients with low-grade non-Hodgkin's lymphoma. In this retrospective case series of 10 patients, we report our early experience using low-dose radiotherapy (usually 2 x2 Gy) for patients with advanced-stage follicular, mucosal associated lymphoid tissue, mantle cell and small lymphocytic lymphomas. Median follow up was 27 weeks. Response rates were high (complete response, 70%; partial response, 20%), the response durable and the toxicity was minimal (no toxicity greater than grade 1). Low-dose irradiation is an effective treatment option for patients with low-grade lymphomas with local symptoms Copyright (2006) Blackwell Publishing Asia Pty Ltd

  6. Assessing the dose values received by patients during conventional radiography X-ray examinations and the technical condition of the equipment used for this purpose.

    Science.gov (United States)

    Bekas, Marcin; Pachocki, Krzysztof A; Waśniewska, Elżbieta; Bogucka, Dagmara; Magiera, Andrzej

    2014-01-01

    X-ray examination is associated with patient exposure to ionizing radiation. Dose values depend on the type of medical procedure used, the X-ray unit technical condition and exposure conditions selected. The aim of this study was to determine the dose value received by patients during certain conventional radiography X-ray examinations and to assess the technical condition of medical equipment used for this purpose. The study covered the total number of 118 conventional diagnostic X-ray units located in the Masovian Voivodeship. The methodology used to assess the conventional diagnostic X-ray unit technical condition and the measurement of the radiation dose rate received by patients are based on test procedures developed by the Department of Radiation Protection and Radiobiology of the National Institute of Public Health - National Institute of Hygiene (Warszawa, Poland) accredited for compliance with PN-EN 17025 standard by the Polish Centre for Accreditation. It was found that 84.7% of X-ray units fully meet the criteria set out in the Polish legislation regarding the safe use of ionizing radiation in medicine, while 15.3% of the units do not meet some of them. The broadest dose value range was recorded for adult patients. Particularly, during lateral (LATl) lumbar spine radiography the recorded entrance surface dose (ESD) values ranged from 283.5 to 7827 µGy (mean: 2183.3 µGy). It is absolutely necessary to constantly monitor the technical condition of all X-ray units, because it affects population exposure to ionizing radiation. Furthermore, it is essential to raise radiographers' awareness of the effects that ionizing radiation exposure can have on the human body.

  7. Verification of the absorbed dose values determined with plane parallel ionization chambers in therapeutic electron beams using ferrous sulfate dosimetry

    International Nuclear Information System (INIS)

    Plaetsen, A. van der; Thierens, H.; Palmans, H.

    2000-01-01

    Absolute and relative dosimetry measurements in clinical electron beams using different detectors were performed at a Philips SL18 accelerator. For absolute dosimetry, ionization chamber measurements with the PTW Markus and PTW Roos plane parallel chambers were performed in water following the recommendations of the TRS-381 Code of Practice, using different options for chamber calibration. The dose results obtained with these ionization chambers using the electron beam calibration method were compared with the dose response of the ferrous sulphate (Fricke) chemical dosimeter. The influence of the choice of detector type on the determination of physical quantities necessary for absolute dose determination was investigated and discussed. Results for d max , R 50 and R p were in agreement within statistical uncertainties when using a diode, diamond or plane parallel chamber. The effective point of measurement for the Markus chamber is found to be shifted 0.5 mm from the front surface of the cavity. Fluence correction factors, h m , for dose determination in electron beams using a PMMA phantom were determined experimentally for both plane parallel chamber types. (author)

  8. A bacterial cocaine esterase protects against cocaine-induced epileptogenic activity and lethality.

    Science.gov (United States)

    Jutkiewicz, Emily M; Baladi, Michelle G; Cooper, Ziva D; Narasimhan, Diwahar; Sunahara, Roger K; Woods, James H

    2009-09-01

    Cocaine toxicity results in cardiovascular complications, seizures, and death and accounts for approximately 20% of drug-related emergency department visits every year. Presently, there are no treatments to eliminate the toxic effects of cocaine. The present study hypothesizes that a bacterial cocaine esterase with high catalytic efficiency would provide rapid and robust protection from cocaine-induced convulsions, epileptogenic activity, and lethality. Cocaine-induced paroxysmal activity and convulsions were evaluated in rats surgically implanted with radiotelemetry devices (N=6 per treatment group). Cocaine esterase was administered 1 minute after a lethal dose of cocaine or after cocaine-induced convulsions to determine the ability of the enzyme to prevent or reverse, respectively, the effects of cocaine. The cocaine esterase prevented all cocaine-induced electroencephalographic changes and lethality. This effect was specific for cocaine because the esterase did not prevent convulsions and death induced by a cocaine analog, (-)-2beta-carbomethoxy-3beta-phenyltropane. The esterase prevented lethality even after cocaine-induced convulsions occurred. In contrast, the short-acting benzodiazepine, midazolam, prevented cocaine-induced convulsions but not the lethal effects of cocaine. The data showed that cocaine esterase successfully degraded circulating cocaine to prevent lethality and that cocaine-induced convulsions alone are not responsible for the lethal effects of cocaine in this model. Therefore, further investigation into the use of cocaine esterase for treating cocaine overdose and its toxic effects is warranted.

  9. Consideration of the ICRP 2006 revised tissue weighting factors on age-dependent values of the effective dose for external photons

    Science.gov (United States)

    Lee, Choonsik; Lee, Choonik; Han, Eun Young; Bolch, Wesley E.

    2007-01-01

    The effective dose recommended by the International Commission on Radiological Protection (ICRP) is the sum of organ equivalent doses weighted by corresponding tissue weighting factors, wT. ICRP is in the process of revising its 1990 recommendations on the effective dose where new values of organs and tissue weighting factors have been proposed and published in draft form for consultation by the radiological protection community. In its 5 June 2006 draft recommendations, new organs and tissues have been introduced in the effective dose which do not exist within the 1987 Oak Ridge National Laboratory (ORNL) phantom series (e.g., salivary glands). Recently, the investigators at University of Florida have updated the series of ORNL phantoms by implementing new organ models and adopting organ-specific elemental composition and densities. In this study, the effective dose changes caused by the transition from the current recommendation of ICRP Publication 60 to the 2006 draft recommendations were investigated for external photon irradiation across the range of ICRP reference ages (newborn, 1-year, 5-year, 10-year, 15-year and adult) and for six idealized irradiation geometries: anterior-posterior (AP), posterior-anterior (PA), left-lateral (LLAT), right-lateral (RLAT), rotational (ROT) and isotropic (ISO). Organ-absorbed doses were calculated by implementing the revised ORNL phantoms in the Monte Carlo radiation transport code, MCNPX2.5, after which effective doses were calculated under the 1990 and draft 2006 evaluation schemes of the ICRP. Effective doses calculated under the 2006 draft scheme were slightly higher than estimated under ICRP Publication 60 methods for all irradiation geometries exclusive of the AP geometry where an opposite trend was observed. The effective doses of the adult phantom were more greatly affected by the change in tissue weighting factors than that seen within the paediatric members of the phantom series. Additionally, dose conversion

  10. Lethal and mutagenic effects of ion beams and γ-rays in Aspergillus oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Toyoshima, Yoshiyuki, E-mail: toyoshima@yamasa.com [Soy Sauce Laboratory, Yamasa Corporation, 2-10-1 Araoicho, Choshi, Chiba 288-0056 (Japan); Takahashi, Akemi; Tanaka, Hisaki; Watanabe, Jun; Mogi, Yoshinobu; Yamazaki, Tatsuo [Soy Sauce Laboratory, Yamasa Corporation, 2-10-1 Araoicho, Choshi, Chiba 288-0056 (Japan); Hamada, Ryoko; Iwashita, Kazuhiro [Fundamental Research Division, National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashihiroshima, Hiroshima 739-0046 (Japan); Satoh, Katsuya; Narumi, Issay [Ion Beam Mutagenesis Research Group, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2012-12-15

    Highlights: ► We investigated the effects of different LET radiation in A. oryzae. ► Both γ-rays and ion beams induced base substitutions, frameshifts, deletions. ► Both γ-rays and ion beams induced genome-wide large-scale mutations in A. oryzae. ► Some differences in the types and frequencies of mutations were found. ► Our results provide new basic insights into the mutation breeding of A. oryzae. - Abstract: Aspergillus oryzae is a fungus that is used widely in traditional Japanese fermentation industries. In this study, the lethal and mutagenic effects of different linear energy transfer (LET) radiation in freeze-dried conidia of A. oryzae were investigated. The lethal effect, which was evaluated by a 90% lethal dose, was dependent on the LET value of the ionizing radiation. The most lethal ionizing radiation among that tested was {sup 12}C{sup 5+} ion beams with an LET of 121 keV/μm. The {sup 12}C{sup 5+} ion beams had a 3.6-times higher lethal effect than low-LET (0.2 keV/μm) γ-rays. The mutagenic effect was evaluated by the frequency of selenate resistant mutants. {sup 12}C{sup 6+} ion beams with an LET of 86 keV/μm were the most effective in inducing selenate resistance. The mutant frequency following exposure to {sup 12}C{sup 6+} ion beams increased with an increase in dose and reached 3.47 × 10{sup −3} at 700 Gy. In the dose range from 0 to 700 Gy, {sup 12}C{sup 5+} ion beams were the second most effective in inducing selenate resistance, the mutant frequency of which reached a maximum peak (1.67 × 10{sup −3}) at 400 Gy. To elucidate the characteristics of mutation induced by ionizing radiation, mutations in the sulphate permease gene (sB) and ATP sulfurylase gene (sC) loci, the loss of function of which results in a selenate resistant phenotype, were compared between {sup 12}C{sup 5+} ion beams and γ-rays. We detected all types of transversions and transitions. For frameshifts, the frequency of a +1 frameshift was the highest in all

  11. Reference values in indicators of patient dose; Valores de referencia en los indicadores de dosis a paciente

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Llorente, P. L.; Hernandez Rodriguez, J.; Ramos Pacho, J. A.; Verde Velasco, J. M.; Fernandez Bordes, M.; Martin Rincon, C.; Montes fuentes, C.; Garcia Repiso, S.; Sena Espinel, E. de; Martin Nunoz, J.

    2011-07-01

    The RD 1976/1999 on Quality Assurance in Diagnostic Radiology laid the foundation for developing the Radiological Protection of Patient compliance with the relevant Directive EURATOM. More than ten years of implementation, we consider an urgent review and update its content due to the legal implications involved as set forth therein, especially in the aspects that have to do with the measurement of patient dose indicators, and more specifically in exploration called complex and CAT.

  12. Dependence of early therapy results and complications on radiation dose values and their fractionation in pre-operative ''afterloading'' technique brachyradiotherapy applied to cervix uteri carcinoma patients

    International Nuclear Information System (INIS)

    Kaminska, G.; Kawczynska, M.

    1984-01-01

    The ''afterloading'' technique with use of Curietron (41 cases) or Selectron (43 cases) apparatus was applied in 83 cervix uteri carcinoma patients in phase 1b (79 cases) and 2a (4 cases). The Wertheim-Magis operation was performed after several weeks. Post-operative histologic investigation showed complete destruction of the tumour in 72% cases; persistent cancer cells in cervix uteri were stated in 11 patients (13%), while lymphatic node metastasis was seen in 14 patients (17%). Supplementary teleradiotherapy was performed in those cases. 39 patients (95%) of the 41 observed during 3 years survived without any cancer symptoms. No explicit relationship between dose administered to vaginal disc and cancer persistence frequency in the cervix uteri was stated. However, such relationship was stated for the dose in point A. In the group of 19 patients who received point A dose of the least 6000 rads, with average TDF value of 135, presence of cancer cells in cervix uteri was not stated in any of the cases. In 7 patients (17%) observed for over 3 years light and medium heavy postradiation complications were stated; in that 5 rectum side complications were stated in patients additionally irradiated from external fields, where the dose absorbed by rectum wall exceeded 8000 rads, with TDF - 150. No complications were observed when the dose was less than 5000 rads and TDF below 100. 16 refs., 1 fig. (author)

  13. Factors influencing circadian rhythms in acetaminophen lethality.

    Science.gov (United States)

    Schnell, R C; Bozigian, H P; Davies, M H; Merrick, B A; Park, K S; McMillan, D A

    1984-01-01

    Experiments were conducted to examine the effects of changes in lighting schedules and food consumption on circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice. Under a normal lighting schedule (light: 06.00-18.00 h), male mice exhibited a circadian rhythm in acetaminophen lethality (peak: 18.00 h; nadir: 06.00, 10.00 h) and an inverse rhythm in hepatic glutathione concentrations (peak: 06.00, 10.00 h; nadir: 18.00 h). Under a reversed lighting schedule (light: 18.00-06.00 h) the glutathione rhythm was reversed and the rhythm in acetaminophen lethality was altered showing greater sensitivity to the drug. Under continuous light, there was a shift in the acetaminophen lethality and the hepatic glutathione rhythms. Under continuous dark, both rhythms were abolished. Under a normal lighting regimen, hepatic glutathione levels were closely correlated with food consumption; i.e., both were increased during the dark phase and decreased during the light phase. Fasting the mice for 12 h abolished the rhythms in acetaminophen lethality and hepatic glutathione levels; moreover, the lethality was increased and the hepatic glutathione levels were decreased. These experiments show that both lighting schedules and feeding can alter the circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice.

  14. Forecasting of the lethality in cases of nonuniform accidental irradiation (experimental studies at external gamma irradiation of rats)

    International Nuclear Information System (INIS)

    Ingilizova, K.

    1983-01-01

    A model is suggested that enables the prediction of death probability for the body (L) within the whole lethality dose range (DL 0 -DL 100 ), on the basis of predetermined physical characteristics: in cases of uneven external wholebody irradiation. Some biological effects of 4 variants of uneven irradiation have been studied, i.e. ventro-dorsal (V-D), dorso-ventral (D-V), cranio-caudal (Cr-Ca) and caudo-cranial (Ca-Cr). The following basic conclusions have been drawn: 1. The study of the biological effects of uneven irradiation, when estimated by the lethality factor, points out the lower efficiency of the former, if compared to even irradiation. 2. The even irradiation lethality in the conducted experiments, according to the ALE data and the postradiation mortality dynamics, is determined basically by the damage of the bloodforming tissue and the animals die of bone marrow syndrome. 3. The uneven irradiation, estimated by the total weight factor, is of lower efficiency than the even one. 4. The radiation-induced hypoplasia of the studied organs is exponential in character. 5. An original model for predicting radiation mortality in cases of uneven irradiation has been constructed. The model gives the possibility of relating the alterations in the index of biological efficiency reduction to the wholebody irradiation factor, as well as to the two systems with highest radiosensitivity: red bone marrow and the small intestine. The model helps determining the numerical value of death probability, depending on the average body irradiation doses and the integral unevenness factors for RBM. (author)

  15. Effective dose estimation from the Hp(10) value measured by film OR TL dosemeter located above the lead apron in medical diagnostic and intervention radiology

    International Nuclear Information System (INIS)

    Trousil, J.; Plichta, J.; Petrova, K.

    2001-01-01

    In medical institutions where the diagnostic and intervention radiology is examined the staff personnel doses reach for a long time the annual limit. State Office for Radiation Safety ordered the research task with a view to: (a) the influence of the dosemeter location on different parts of the body on the reliability of E value estimation by means of the value which is measured on the standard body location - left part of the chest above the lead apron. (b) the influence of the protective lead apron (neck, spectacles) with known lead equivalent on the E and H T value determination. In this contribution we present the results of this experimental study including the recommendation for the number and location on the body of dosemeters which are needed for the reliable estimation of E value. (authors)

  16. Photoreactivable sector of lethal damage in ultraviolet-irradiated Escherichia coli cells

    International Nuclear Information System (INIS)

    Balgavy, P.

    1976-01-01

    The photoreactivable sector of lethal damage in Escherichia coli Bsub(s-1), Escherichia coli B/r Hcr - and Escherichia coli B/r Hcr + cells after ultraviolet irradiation at 254 nm is 0.823 +- 0.004, 0.70 +- 0.01 and 0.53 +- 0.06, respectively, at 99% confidence limits. For the low values of the photoreactivable sector in the B/r Hcr - and B/r Hcr + strains are likely to be responsible dark repair processes which eliminate lethal damage, brought about by pyrimidine dimers, preferably in comparison with lethal damage caused by photoproducts of another type. (author)

  17. Organ S values and effective doses for family members exposed to adult patients following I-131 treatment: A Monte Carlo simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Young [Department of Radiation Oncology, University of Arkansas Medical Sciences, Little Rock, Arkansas 72205 (United States); Lee, Choonsik [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Mcguire, Lynn; Brown, Tracy L. Y. [Department of Radiology, Division of Nuclear Medicine, University of Arkansas Medical Sciences, Little Rock, Arkansas 72205 (United States); Bolch, Wesley E. [J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2013-08-15

    Purpose: To calculate organ S values (mGy/Bq-s) and effective doses per time-integrated activity (mSv/Bq-s) for pediatric and adult family members exposed to an adult male or female patient treated with I-131 using a series of hybrid computational phantoms coupled with a Monte Carlo radiation transport technique.Methods: A series of pediatric and adult hybrid computational phantoms were employed in the study. Three different exposure scenarios were considered: (1) standing face-to-face exposures between an adult patient and pediatric or adult family phantoms at five different separation distances; (2) an adult female patient holding her newborn child, and (3) a 1-yr-old child standing on the lap of an adult female patient. For the adult patient model, two different thyroid-related diseases were considered: hyperthyroidism and differentiated thyroid cancer (DTC) with corresponding internal distributions of {sup 131}I. A general purpose Monte Carlo code, MCNPX v2.7, was used to perform the Monte Carlo radiation transport.Results: The S values show a strong dependency on age and organ location within the family phantoms at short distances. The S values and effective dose per time-integrated activity from the adult female patient phantom are relatively high at shorter distances and to younger family phantoms. At a distance of 1 m, effective doses per time-integrated activity are lower than those values based on the NRC (Nuclear Regulatory Commission) by a factor of 2 for both adult male and female patient phantoms. The S values to target organs from the hyperthyroid-patient source distribution strongly depend on the height of the exposed family phantom, so that their values rapidly decrease with decreasing height of the family phantom. Active marrow of the 10-yr-old phantom shows the highest S values among family phantoms for the DTC-patient source distribution. In the exposure scenario of mother and baby, S values and effective doses per time-integrated activity to

  18. Organ S values and effective doses for family members exposed to adult patients following I-131 treatment: A Monte Carlo simulation study

    International Nuclear Information System (INIS)

    Han, Eun Young; Lee, Choonsik; Mcguire, Lynn; Brown, Tracy L. Y.; Bolch, Wesley E.

    2013-01-01

    Purpose: To calculate organ S values (mGy/Bq-s) and effective doses per time-integrated activity (mSv/Bq-s) for pediatric and adult family members exposed to an adult male or female patient treated with I-131 using a series of hybrid computational phantoms coupled with a Monte Carlo radiation transport technique.Methods: A series of pediatric and adult hybrid computational phantoms were employed in the study. Three different exposure scenarios were considered: (1) standing face-to-face exposures between an adult patient and pediatric or adult family phantoms at five different separation distances; (2) an adult female patient holding her newborn child, and (3) a 1-yr-old child standing on the lap of an adult female patient. For the adult patient model, two different thyroid-related diseases were considered: hyperthyroidism and differentiated thyroid cancer (DTC) with corresponding internal distributions of 131 I. A general purpose Monte Carlo code, MCNPX v2.7, was used to perform the Monte Carlo radiation transport.Results: The S values show a strong dependency on age and organ location within the family phantoms at short distances. The S values and effective dose per time-integrated activity from the adult female patient phantom are relatively high at shorter distances and to younger family phantoms. At a distance of 1 m, effective doses per time-integrated activity are lower than those values based on the NRC (Nuclear Regulatory Commission) by a factor of 2 for both adult male and female patient phantoms. The S values to target organs from the hyperthyroid-patient source distribution strongly depend on the height of the exposed family phantom, so that their values rapidly decrease with decreasing height of the family phantom. Active marrow of the 10-yr-old phantom shows the highest S values among family phantoms for the DTC-patient source distribution. In the exposure scenario of mother and baby, S values and effective doses per time-integrated activity to the

  19. Recommended values for the distribution coefficient (Kd) to be used in dose assessments for decommissioning the Zion Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-09-24

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant. The site contains two reactor Containment Buildings, a Fuel Building, an Auxiliary Building, and a Turbine Building that may be contaminated. The current decommissioning plan involves removing all above grade structures to a depth of 3 feet below grade. The remaining underground structures will be backfilled. The remaining underground structures will contain low amounts of residual licensed radioactive material. An important component of the decommissioning process is the demonstration that any remaining activity will not cause a hypothetical individual to receive a dose in excess of 25 mrem/y as specified in 10CFR20 SubpartE.

  20. Recommended values for the distribution coefficient (Kd) to be used in dose assessments for decommissioning the Zion Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan T.

    2014-06-09

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant. The site contains two reactor Containment Buildings, a Fuel Building, an Auxiliary Building, and a Turbine Building that may be contaminated. The current decommissioning plan involves removing all above grade structures to a depth of 3 feet below grade. The remaining underground structures will be backfilled. The remaining underground structures will contain low amounts of residual licensed radioactive material. An important component of the decommissioning process is the demonstration that any remaining activity will not cause a hypothetical individual to receive a dose in excess of 25 mrem/y as specified in 10CFR20 SubpartE.

  1. Influence of the neutron flux shape on the value of absorbed neutron dose; Uticaj oblika neutronskog spektra na vrednost apsorbovane doze neutrona

    Energy Technology Data Exchange (ETDEWEB)

    Miric, I; Miric, P [Institute of nuclear sciences Boris Kidric, Vinca, Beograd (Yugoslavia)

    1974-07-01

    This paper deals with the study od specific doses dependence on the type and approximation procedures of neutron spectra. Values of specific dose rates (dose per neutron cm{sub 2}) were analysed for neutron spectra from RB reactor in Vinca, Crac facility in Valduc (France) and HPRR reactor in Oak Ridge (USA). Data used in this analysis were obtained by methods used in Harwell (AERE), Oak Ridge (ORNL), Chalk River (AECL), CEN de Cadarache (CEA) and in the Boris Kidric Institute (IBK). Specific absorbed neutron doses were determined for each of the estimated spectra and presented in the form of kerma/(n.cm{sup -2}) and rad/((n.cm{sup -2}) units. The obtained results have shown the influence of the flux approximation procedure on the values of conversion factors for obtaining neutron doses from neutron flux. U okviru ovog rada radjeno je na ispitivanju zavisnosti specificnih doza od vrste i nacina aproksimacije neutronskog spektra. U radu su analizirane vrednosti specificnih doza (doza po n.cm{sup -2}) za neutronske spektre koji se dobijaju oko sledecih nuklearnih postrojenja: reaktora RB u Vinci, postrojenja CRAC u Valduc-u (Francuska), reaktora HPRR u Oak Ridge-u (SAD). Za analizu su korisceni podaci dobijeni metodama koje se koriste u nuklearnim centrima Harwell (AERE), Oak Ridge-u (ORNL), Chalk River-u (AECL), CEN de Cadarache (CEA) i Institutu Boris Kidric (IBK). Za svaki procenjeni spektar odredjene su specificne apsorbovane doze neutrona izrazene u kerma/(n.cm{sup -2}) i rad/(n.cm{sup -2}) jedinicama. Dobijeni rezultati su pokazali koliko nacin aproksimacije spektra utice na vrednost konverzionih faktora koji sluze za prelazak sa fluksa na dozu neutrona (author)

  2. Transporting Patients with Lethal Contagious Infections

    National Research Council Canada - National Science Library

    Swartz, Colleen

    2002-01-01

    .... The AIT is a unique military medical team capable of worldwide air evacuation and management of a limited number of patients who are potentially exposed to known and unknown lethal communicable...

  3. Lethal and Sub-lethal Effects of Four Insecticides on the Aphidophagous Coccinellid Adalia bipunctata (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Depalo, Laura; Lanzoni, Alberto; Masetti, Antonio; Pasqualini, Edison; Burgio, Giovanni

    2017-12-05

    Conventional insecticide assays, which measure the effects of insecticide exposure on short-term mortality, overlook important traits, including persistence of toxicity or sub-lethal effects. Therefore, such approaches are especially inadequate for prediction of the overall impact of insecticides on beneficial arthropods. In this study, the side effects of four modern insecticides (chlorantraniliprole, emamectin benzoate, spinosad, and spirotetramat) on Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by exposition on treated potted plants. In addition to investigation of acute toxicity and persistence of harmful activity in both larvae and adults of A. bipunctata, demographic parameters were evaluated, to provide a comprehensive picture of the nontarget effects of these products. Field doses of the four insecticides caused detrimental effects to A. bipunctata; but in different ways. Overall, spinosad showed the best toxicological profile among the products tested. Emamectin benzoate could be considered a low-risk insecticide, but had high persistence. Chlorantraniliprole exhibited lethal effects on early instar larvae and adults, along with a long-lasting activity, instead spirotetramat showed a low impact on larval and adult mortality and can be considered a short-lived insecticide. However, demographic analysis demonstrated that chlorantraniliprole and spirotetramat caused sub-lethal effects. Our findings highlight that sole assessment of mortality can lead to underestimation of the full impact of pesticides on nontarget insects. Demographic analysis was demonstrated to be a sensitive method for detection of the sub-lethal effects of insecticides on A. bipunctata, and this approach should be considered for evaluation of insecticide selectivity. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Comparison of the lethal effects of chemical warfare nerve agents across multiple ages.

    Science.gov (United States)

    Wright, Linnzi K M; Lee, Robyn B; Vincelli, Nicole M; Whalley, Christopher E; Lumley, Lucille A

    2016-01-22

    Children may be inherently more vulnerable than adults to the lethal effects associated with chemical warfare nerve agent (CWNA) exposure because of their closer proximity to the ground, smaller body mass, higher respiratory rate, increased skin permeability and immature metabolic systems. Unfortunately, there have only been a handful of studies on the effects of CWNA in pediatric animal models, and more research is needed to confirm this hypothesis. Using a stagewise, adaptive dose design, we estimated the 24h median lethal dose for subcutaneous exposure to seven CWNA in both male and female Sprague-Dawley rats at six different developmental times. Perinatal (postnatal day [PND] 7, 14 and 21) and adult (PND 70) rats were more susceptible than pubertal (PND 28 and 42) rats to the lethal effects associated with exposure to tabun, sarin, soman and cyclosarin. Age-related differences in susceptibility were not observed in rats exposed to VM, Russian VX or VX. Published by Elsevier Ireland Ltd.

  5. Self-reported smoking effects and comparative value between cigarettes and high dose e-cigarettes in nicotine-dependent cigarette smokers.

    Science.gov (United States)

    McPherson, Sterling; Howell, Donelle; Lewis, Jennifer; Barbosa-Leiker, Celestina; Bertotti Metoyer, Patrick; Roll, John

    2016-04-01

    The objective of this experiment was to evaluate the comparative value of cigarettes versus high dose e-cigarettes among nicotine-dependent cigarette smokers when compared with money or use of their usual cigarette brand. The experiment used a within-subject design with four sessions. After baseline assessment, participants attended two 15-min unrestricted smoking sessions: one cigarette smoking session and one e-cigarette smoking session. Participants then attended two multiple-choice procedure (MCP) sessions: a session comparing cigarettes and money and a session comparing e-cigarettes and money. Participants (n=27) had used cigarettes regularly, had never used e-cigarettes, and were not currently attempting to quit smoking. The sample consisted primarily of males (72%), with a mean age of 34 years. When given the opportunity to choose between smoking a cigarette or an e-cigarette, participants chose the cigarette 73.9% of the time. Findings from the MCP demonstrated that after the first e-cigarette exposure sessions, the crossover value for cigarettes ($3.45) was significantly higher compared with the crossover value for e-cigarettes ($2.73). The higher participant preference, self-reported smoking effects, and higher MCP crossover points indicate that cigarettes have a higher comparative value than high dose e-cigarettes among e-cigarette naive smokers.

  6. Experiences in therapy for lethal midline granuloma

    International Nuclear Information System (INIS)

    Tosaka, Kaoru; Ishikawa, Takeru

    1982-01-01

    Four cases of the lethal midline granuloma or malignant granuloma of the nose were treated by irradiation and chemotherapy, which are generally prescribed for malignant lymphomas. Clinical, histological and laboratory examination indicated that they were the lethal midline granuloma and clearly differentiated from Wegener's granulomatosis or malignant lymphoma. All of the cases exhibited primary remission. The four cases were observed up to 38, 22, 14, and 10 months since the beginning of the therapy, showing no local or general recurrence. (author)

  7. Toxicidad oral a 60 días del aceite de sacha inchi (Plukenetia volubilis L. y linaza (Linum usitatissimum L. y determinación de la dosis letal 50 en roedores Oral toxicity at 60-days of sacha inchi oil (Plukenetia volubilis L. and linseed (Linum usitatissimum L., and determination of lethal dose 50 in rodents

    Directory of Open Access Journals (Sweden)

    Arilmi Gorriti

    2010-09-01

    Full Text Available Objetivos. Evaluar la toxicidad oral a 60 días y determinar la dosis letal 50 (DL 50 de los aceites crudos de sacha inchi (Plukenetia volubilis L. y linaza (Linum ussitatisimum en ratas Holtzman y en ratones cepa Balb C57, respectivamente. Materiales y métodos. Para la evaluación de la toxicidad oral a dosis repetida por 60 días se utilizó 24 ratas macho Holtzman divididos en tres grupos de ocho cada uno, los grupos fueron: solución salina fisiológica 4 mL/kg (SSF, aceite de sacha inchi 0,5 mL/kg (SI05 y aceite de linaza 0,5 mL/kg (L05, durante el experimento se controló semanalmente el peso corporal y signos de toxicidad en los grupos investigados, así como colesterol total, HDL, triglicéridos, glucosa, urea, TGP y fosfatasa alcalina a los 30 y 60 días de iniciado el experimento. Para la evaluación de la DL50 se usó ratones macho cepa Balb C57 en grupos de diez animales, se administró por vía oral dosis crecientes de aceites crudos hasta alcanzar 1 mL/kg (37 g/kg; Resultados. Los parámetros séricos en las ratas indican que no existe toxicidad alguna a los 60 días y que la administración de los aceites disminuyeron los niveles de colesterol, triglicéridos e incrementaron el HDL con respecto al grupo control. La DL50 muestra que los aceites crudos de sacha inchi y linaza presentan dosis por encima de los 37 g/kg de masa corporal. Conclusiones. Los aceites de sacha inchi y linaza son inocuos a 60 días y presentan una DL50 por encima de los 37 g/kg de animal.Objectives. To evaluate the oral toxicity at 60 days and to determine the lethal dose 50 (LD 50 of raw sacha inchi (Plukenetia volubilis L. and linseed (Linum ussitatisimum oils in Holtzman rats and mice of the strain Balb C57 respectively. Materials and methods. For the evaluation of the oral toxicity of repeated doses for 60 days, 24 male Holtzman rats were used, divided in three groups of 8 each, the groups were: physiologic saline solution 4 mL/kg (FSS, sacha inchi oil

  8. Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11

    International Nuclear Information System (INIS)

    Eckerman, K.F.; Wolbarst, A.B.; Richardson, A.C.B.

    1988-09-01

    Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation protection guidance. They are intended to serve as the basis for regulations setting upper bounds on the inhalation and ingestion of, and submersion in, radioactive materials in the workplace. The report also includes tables of exposure-to-dose conversion factors, for general use in assessing average individual committed doses in any population that is adequately characterized by Reference Man. 38 refs

  9. Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11

    Energy Technology Data Exchange (ETDEWEB)

    Eckerman, K.F.; Wolbarst, A.B.; Richardson, A.C.B.

    1988-09-01

    Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation protection guidance. They are intended to serve as the basis for regulations setting upper bounds on the inhalation and ingestion of, and submersion in, radioactive materials in the workplace. The report also includes tables of exposure-to-dose conversion factors, for general use in assessing average individual committed doses in any population that is adequately characterized by Reference Man. 38 refs.

  10. The value of low-dose prospective ECG-gated dual-source CT angiography in the diagnosis of coarctation of the aorta in infants and children

    Energy Technology Data Exchange (ETDEWEB)

    Nie, P. [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Wang, X., E-mail: wxming369@yahoo.com.cn [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Cheng, Z.; Duan, Y.; Ji, X. [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Chen, J. [CT Research Collaboration, Siemens, Beijing (China); Zhang, H. [Department of Cardiovascular Surgery, Shandong Provincial Hospital, Jinan, Shandong (China)

    2012-08-15

    Aim: To investigate the value of prospective electrocardiogram (ECG)-gated dual-source computed tomography (DSCT) in the diagnosis of coarctation of the aorta (CoA). Materials and methods: Seventeen patients clinically suspected of having CoA underwent prospective ECG-gated DSCT angiography and transthoracic echocardiography (TTE). Surgery was performed in all patients. The diagnostic accuracy of DSCT angiography and TTE was compared with the surgical findings as the reference standard. Image quality was evaluated using a five-point scale. Effective radiation dose was calculated from the dose-length product (DLP). Results: CoA was diagnosed in 17 patients by DSCT angiography and in 16 patients by TTE. A total of 46 separate cardiovascular abnormalities were confirmed by surgical findings. The diagnostic accuracy of DSCT angiography and TTE was 96.32% and 97.06%, respectively. There was no significant difference in the diagnostic accuracy between DSCT angiography and TTE ({chi}{sup 2} = 0, p > 0.05). The mean score of image quality was 4.2 {+-} 0.8. The mean effective dose was 0.69 {+-} 0.09 mSv. Conclusion: Prospective ECG-gated DSCT with a low radiation dose is a valuable technique in the diagnosis of CoA in infants and children.

  11. Radiation lethality in the opossum

    International Nuclear Information System (INIS)

    Prasad, N.; Bushong, S.C.; North, L.B.; Thornby, J.

    1976-01-01

    Groups of male opossum (Didelphis virginiana) at 6 months of age were exposed to 350, 500, 550, 600, 650, 700, and 750 rad of whole-body 60 Co radiation at a midline dose rate of 125 rad/min. The 30-day LD 50 was 511 rad with 95% confidence limits of 454 to 576 rad. The overall mean survival time was 17.9 days and the highest incidence of death occurred on the 16th day

  12. Radiation lethality in the opossum

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, N.; Bushong, S.C.; North, L.B.; Thornby, J.

    1976-12-01

    Groups of male opossum (Didelphis virginiana) at 6 months of age were exposed to 350, 500, 550, 600, 650, 700, and 750 rad of whole-body /sup 60/Co radiation at a midline dose rate of 125 rad/min. The 30-day LD/sub 50/ was 511 rad with 95% confidence limits of 454 to 576 rad. The overall mean survival time was 17.9 days and the highest incidence of death occurred on the 16th day.

  13. OPAL shield design performance assessment. Comparison of measured dose rates against the corresponding design calculated values. A designer perspective

    Energy Technology Data Exchange (ETDEWEB)

    Brizuela, Martin; Albornoz, Felipe [INVAP SE, Av. Cmte. Piedrabuena, Bariloche (Argentina)

    2012-03-15

    A comparison of OPAL shielding calculations against measurements carried out during Commissioning, is presented for relevant structures such as the reactor block, primary shutters, neutron guide bunker, etc. All the results obtained agree very well with the measured values and contribute to establish the confidence on the calculation tools (MCNP4, DORT, etc.) and methodology used for shielding design. (author)

  14. 5-Lipoxygenase Deficiency Reduces Acetaminophen-Induced Hepatotoxicity and Lethality

    Directory of Open Access Journals (Sweden)

    Miriam S. N. Hohmann

    2013-01-01

    Full Text Available 5-Lipoxygenase (5-LO converts arachidonic acid into leukotrienes (LTs and is involved in inflammation. At present, the participation of 5-LO in acetaminophen (APAP-induced hepatotoxicity and liver damage has not been addressed. 5-LO deficient (5-LO-/- mice and background wild type mice were challenged with APAP (0.3–6 g/kg or saline. The lethality, liver damage, neutrophil and macrophage recruitment, LTB4, cytokine production, and oxidative stress were assessed. APAP induced a dose-dependent mortality, and the dose of 3 g/kg was selected for next experiments. APAP induced LTB4 production in the liver, the primary target organ in APAP toxicity. Histopathological analysis revealed that 5-LO-/- mice presented reduced APAP-induced liver necrosis and inflammation compared with WT mice. APAP-induced lethality, increase of plasma levels of aspartate aminotransferase and alanine aminotransferase, liver cytokine (IL-1β, TNF-α, IFN-γ, and IL-10, superoxide anion, and thiobarbituric acid reactive substances production, myeloperoxidase and N-acetyl-β-D-glucosaminidase activity, Nrf2 and gp91phox mRNA expression, and decrease of reduced glutathione and antioxidant capacity measured by 2,2′-azinobis(3-ethylbenzothiazoline 6-sulfonate assay were prevented in 5-LO-/- mice compared to WT mice. Therefore, 5-LO deficiency resulted in reduced mortality due to reduced liver inflammatory and oxidative damage, suggesting 5-LO is a promising target to reduce APAP-induced lethality and liver inflammatory/oxidative damage.

  15. Reproductive-phase and interphase lethal cell damage after irradiation and treatment with cytostatics

    International Nuclear Information System (INIS)

    Hagemann, G.

    1979-01-01

    After X-ray irradiation of manual cells, two lethal fractions occur due to reproductive and interphase death under low and high radiation doses. The damage kinetics on which this fact is based is compared with hypothetical tumour frequencies and leucemia induction caused in experiments. The reproductive-lethal damage can be manifested by means of colony size spectrometry, with the median colony size class differences (MCD) serving as measure for the damage found. The simultaneous effects of the cytostatics BLEOMYCIN or ICRF 159 and X-rays on reproductive lethal and interphase-lethal damage are measured by means of MCD and survival fraction, and the additive and intensifying effect' is judged with the help of suitably defined terms. This shows that the clinically used ICRF 159 has an additive effect on interphase-lethal and a sub-additive effect on reproductive-lethal cell damage. Thus, favourable results may be expected for the electivity factor in fractionated irradiation and with regard to delayed damage in healthy tissue. (orig.) 891 MG/orig. 892 RDG [de

  16. Genetic injury in hybrid male mice exposed to low doses of 60CO γ-rays or fission neutrons. 1

    International Nuclear Information System (INIS)

    Grahn, D.; Carnes, B.A.; Farrington, B.H.; Lee, C.H.

    1984-01-01

    Young adult male B6CF 1 mice were exposed to single whole body doses of fission neutrons or 60 Co γ rays. Postspermatogonial dominant lethal injury, incidence of reciprocal chromosome translocations induced in spermatogonia, incidence of abnormal epididymal sperm 4-6 weeks after exposure, and testis weight loss 3-6 weeks after exposure were all measured. Significant effects were seen at 1 and 2.5 rad of neutrons consistent with extrapolation from higher doses, with the exception of dominant lethal mutations, which occurred in significant excess of expectation. Dose-response functions were linear or linear-quadratic, depending upon end point, radiation quality, and dose range. For translocation frequencies, the D 2 term was negative for neutron and positive for γ-ray irradiations. RBE values varied with dose and end point. For testis weight loss and abnormal sperm over the full dose range, the RBEs were between 5 and 6. They were between 7 and 9 at lower doses (< 10 rad) for translocations. RBEs for postimplantation and total dominant lethal rates were 5-6 above 10 rad and 10-14 below 10 rad. The RBEs for preimplant losses were between 15 and 25 above 10 rad and possibly higher below 10 rad, although the data are statistically 'noisy'. (Auth.)

  17. Lethality of patients with rheumatoid arthritis depending on adalimumab administration: imitation modeling

    Directory of Open Access Journals (Sweden)

    D V Goryachev

    2009-01-01

    Full Text Available Lethality of pts with rheumatoid arthritis (RA exceeds mortality values in general population. Possibility of disease modifying anti-rheumatic drugs (DMARD influence on RA pts lethality has been widely discussed lately in scientific works. Objective. To determine possible lethality diminishment in Russian population of RA pts with one of biological drugs TNFα antagonist adalimumab. Material and methods. Model construction is based on the fact of lethality dependence on pt functional state assessed by HAQ. Model simulating progression of functional disability in pts with RA visiting medical institutions of Russia was made (RAISER study. 3 model variants for imitation of consecutive change of DMARDs including adalimumab were done. First consecution assessed DMARD change in the next chain: adalimumab-methotrexate-sulfasalazine-leflunomide-azathioprine-cyclosporine-palliative therapy. Second consecution: adalimumab administration after failure of first 3 DMARDs. Third consecution considered only change of synthetic DMARDs without adalimumab inclusion. Model imitated participation of 3000 pts in every consecution. Prognosis horizon was 12 years. Age of pts and initial HAQ distribution were get from results of epidemiological RAISER study. Calculation was done on the base of elevation of standardized lethality level (SLL in population of RA pts in average from 135% to 300%. SLL values from 80 to 320% were used depending on functional disability degree with converting to Russian values of age-specific lethality coefficient for 1999. Results. Lethality in treatment consecutions including adalimumab was significantly lower. To the end of 12th year in group not using adalimumab, using it at once and using it after 376 DMARDs respectively 65,1%, 71,6% and 71,1% of pts were still alive. Conclusion. Significant decrease of lethality with adalimumab inclusion in consecution of DMARD change during treatment of RA pts was demonstrated with imitation modeling

  18. Models for pulmonary lethality and morbidity after irradiation from internal and external sources

    International Nuclear Information System (INIS)

    Scott, B.R.; Filipy, R.E.; Hahn, E.F.

    1989-05-01

    This report provides a hazard-function model for estimating the risk of death from radiation pneumonitis and/or pulmonary fibrosis following a light-water nuclear power accident. A similar model is also provided for estimating the prevalence of respiratory functional morbidity among those that survive death from acute effects. Hazard-function models for lethality and for morbidity were constructed using the cumulative hazard estimator H, which is related to the risk estimator R through the equation R = 1-exp(-H). The estimator H can be calculated using information provided in the report. The method of calculation depends on the exposure scenario. In general, the total normalized dose X for lethality or for morbidity is calculated. For lethality, X = 1 corresponds to a median lethal dose (LD 50 ); for morbidity, X = 1 corresponds to a median effective dose (ED 50 ). H is related to X by the equation H = 1n(2)X/sup V/, where V depends on the type of radiation (or radiations) involved. Contributions to X can arise from each of two main modes of exposure: (1) brief exposure of the lung, at a relatively high dose rate, to mainly external gammas, followed by (2) chronic internal alpha, and/or beta, and/or gamma irradiation of the lung. Equations are provided for calculating the contributions to X from both modes of exposure. 73 refs., 16 figs., 2 tabs

  19. [Study of personal best value of peak expiratory flow in patients with asthma--comparison of the highest value of daily PEF under good control and the highest value of daily PEF obtained after using repeated inhaled beta2-agonist during high-dose inhaled steroid treatment].

    Science.gov (United States)

    Watanabe, Naoto; Makino, Sohei; Kihara, Norio; Fukuda, Takeshi

    2008-12-01

    In the guideline for asthma management, it is important to find the personal best value of peak expiratory flow (best PEF). Recently, we have substituted the highest value of PEF in daily life under good control (daily highest PEF) for the best PEF. In the present study, we considered whether the daily highest PEF could be used as the best PEF or not. Subjects were 30 asthmatics who were well controlled but whose baseline PEF values were less than 80 percent of predicted values. We compared the daily highest PEF and the highest of PEF obtained after repeated inhaled beta2-agonist (salbutamol MDI every 20 minutes three times). All subjects then received 1600 microg/day of beclomethasone dipropionate (BDP) for 4 to 8 weeks. We studied the effect of high-dose inhaled steroid treatment on each PEF value and compared the daily highest PEF and the highest PEF obtained after using repeated salbutamol MDI during high dose inhaled steroid therapy on the examination day again. The baseline PEF, daily highest PEF and the highest PEF obtained after salbutamol MDI were significantly less than the each values obtained after high-dose BDP. The best PEF value of them was the value obtained after repeated salbutamol MDI during high dose BDP. We suggest that the daily highest PEF under good control is not a substitute for best PEF because it changes according to the degree of improvement of airway inflammation. We recommend that a course of high dose inhaled steroid is effective in finding the best value of PEF for each individual with moderate asthma.

  20. Determination of effective dose rate reference values in São José do Sabugi, PB, Brazil

    International Nuclear Information System (INIS)

    Medeiros, Nilson V. da S.; Santos Júnior, José A. dos; Amaral, Romilton dos S.; Santos, Josineide M. do N.; Araújo, Eduardo E.N. de; Santos Junior, Otávio P. dos; Correia, Filipe L. de B.; Silveira, Patrícia B.

    2017-01-01

    Brazil has some areas with elevated concentration of uranium and/or thorium, such as Guarapari in the State of Espírito Santo, Poços de Caldas in Minas Gerais and regions between the States of Pernambuco and Paraíba.The Seridó region, in the State of Paraiba, consists of rocks classified as pegmatites, gneisses and feldspars, with high level of uranium ores. The high levels of primordial radionuclides have been the focus of the studies performed in the area, specifically in the uranium deposit of Espinharas and some adjacent municipalities. The aim of this work was to carry out 'in situ' measurements in the city of São José do Sabugi, Paraíba. Measurements were done using a portable gamma discriminator with combined NaI (Tl) and BGO probe, coupled to a motor vehicle that allowed to monitor 520 points in the urban and rural areas of said municipality, obtaining effective dose rates ranging from 0.7 to 1.56 mSv.y -1 and averages of 0.26 mSv.y -1 and 0.87 mSv.y -1 , respectively. The results obtained for radiometry of this municipality allow to conclude that the urban and rural areas meet the criteria established by UNSCEAR for areas considered as low background radiation. With this work, reference parameters were established for radiometric characterization of the surrounding municipalities to the uranium deposit of Espinharas. (author)

  1. Low radiation dose non-contrast cardiac CT: is it of value in the evaluation of mechanical aortic valve

    International Nuclear Information System (INIS)

    Bazeed, Mohamed Fayez; Moselhy, Mohamed Saleh; Rezk, Ahmad Ibrahim; Al-Murayeh, Mushabab Ayedh

    2012-01-01

    Background: Prosthetic bileaflet mechanical valve function has been traditionally evaluated using echocardiography and fluoroscopy. Multidetector computed tomography (MDCT) is a novel technique for cardiac evaluation. Purpose: To evaluate bileaflet mechanical aortic valves using a low-milliampere (mA), non-contrast MDCT protocol with a limited scan range. Material and Methods: Forty patients with a bileaflet mechanical aortic valve were evaluated using a non-contrast, low-mA, ECG-gated 64 MDCT protocol with a limited scan range. MDCT findings of opening and closing valve angles were correlated to fluoroscopy and echocardiography. Also, the valve visibility was evaluated on MDCT and fluoroscopy according to a 3-point grading scale. Results: The visualization score with the MDCT was significantly superior to the fluoroscopy (3 vs. 2.7). A strong correlation was noted between the opening (r = 0.82) and closing (r = 0.96) valve angles with MDCT and fluoroscopy without a statistically significant difference (P = 0.31 and 0.16, respectively). The mean effective radiation dose of the suggested protocol was 4 ± 0.5 mSv. Five valves were evaluated using transesophageal echocardiography because the valves were difficult to evaluate with transthoracic echocardiography, and all of these valves were evaluated optimally with MDCT. A high-pressure gradient was noted in nine valves, and the MDCT showed that seven of these valves inadequately opened, and two valves opened well, which resulted in patient valve mismatch. Incomplete valve closure was noted in five valves, and the echocardiography showed significant transvalvular regurgitation in all five valves. Conclusion: MDCT can provide a precise measurement of valve function and can potentially evaluate high-pressure gradients and transvalvular regurgitation

  2. Low radiation dose non-contrast cardiac CT: is it of value in the evaluation of mechanical aortic valve

    Energy Technology Data Exchange (ETDEWEB)

    Bazeed, Mohamed Fayez (Dept. of Diagnostic Radiology, Faculty of Medicine, Mansoura Univ. (Egypt)), email: m_bazeed@yahoo.com; Moselhy, Mohamed Saleh (Cardiology Dept. Faculty of Medicine, Suez Canal Univ. (Egypt)); Rezk, Ahmad Ibrahim (Dept. of Cardiac Surgery, Faculty of Medicine, Aim Shams Univ. (Egypt)); Al-Murayeh, Mushabab Ayedh (Dept. of Cardiac Services, Armed Forces Hospitals Southern Region (Saudi Arabia))

    2012-05-15

    Background: Prosthetic bileaflet mechanical valve function has been traditionally evaluated using echocardiography and fluoroscopy. Multidetector computed tomography (MDCT) is a novel technique for cardiac evaluation. Purpose: To evaluate bileaflet mechanical aortic valves using a low-milliampere (mA), non-contrast MDCT protocol with a limited scan range. Material and Methods: Forty patients with a bileaflet mechanical aortic valve were evaluated using a non-contrast, low-mA, ECG-gated 64 MDCT protocol with a limited scan range. MDCT findings of opening and closing valve angles were correlated to fluoroscopy and echocardiography. Also, the valve visibility was evaluated on MDCT and fluoroscopy according to a 3-point grading scale. Results: The visualization score with the MDCT was significantly superior to the fluoroscopy (3 vs. 2.7). A strong correlation was noted between the opening (r = 0.82) and closing (r = 0.96) valve angles with MDCT and fluoroscopy without a statistically significant difference (P = 0.31 and 0.16, respectively). The mean effective radiation dose of the suggested protocol was 4 +- 0.5 mSv. Five valves were evaluated using transesophageal echocardiography because the valves were difficult to evaluate with transthoracic echocardiography, and all of these valves were evaluated optimally with MDCT. A high-pressure gradient was noted in nine valves, and the MDCT showed that seven of these valves inadequately opened, and two valves opened well, which resulted in patient valve mismatch. Incomplete valve closure was noted in five valves, and the echocardiography showed significant transvalvular regurgitation in all five valves. Conclusion: MDCT can provide a precise measurement of valve function and can potentially evaluate high-pressure gradients and transvalvular regurgitation

  3. Determination of effective dose rate reference values in São José do Sabugi, PB, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Nilson V. da S.; Santos Júnior, José A. dos; Amaral, Romilton dos S.; Santos, Josineide M. do N.; Araújo, Eduardo E.N. de; Santos Junior, Otávio P. dos; Correia, Filipe L. de B., E-mail: nilson.medeiros@ufpe.br, E-mail: jaraujo@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Grupo de Radioecologia; Rojas, Lino A.V., E-mail: linomarvic@gmail.com [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear, La Habana (Cuba); Silveira, Patrícia B., E-mail: pbrandao@cnen.gov.br [Centro Regional de Ciências Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2017-07-01

    Brazil has some areas with elevated concentration of uranium and/or thorium, such as Guarapari in the State of Espírito Santo, Poços de Caldas in Minas Gerais and regions between the States of Pernambuco and Paraíba.The Seridó region, in the State of Paraiba, consists of rocks classified as pegmatites, gneisses and feldspars, with high level of uranium ores. The high levels of primordial radionuclides have been the focus of the studies performed in the area, specifically in the uranium deposit of Espinharas and some adjacent municipalities. The aim of this work was to carry out 'in situ' measurements in the city of São José do Sabugi, Paraíba. Measurements were done using a portable gamma discriminator with combined NaI (Tl) and BGO probe, coupled to a motor vehicle that allowed to monitor 520 points in the urban and rural areas of said municipality, obtaining effective dose rates ranging from 0.7 to 1.56 mSv.y{sup -1} and averages of 0.26 mSv.y{sup -1}and 0.87 mSv.y{sup -1}, respectively. The results obtained for radiometry of this municipality allow to conclude that the urban and rural areas meet the criteria established by UNSCEAR for areas considered as low background radiation. With this work, reference parameters were established for radiometric characterization of the surrounding municipalities to the uranium deposit of Espinharas. (author)

  4. Value of the Serum Thyroglobulin Level Alteration at the First High Dose Radioiodine Treatment in Patients with Differentiated Thyroid Carcinoma

    International Nuclear Information System (INIS)

    Nam, Hyun Yeol; Kim, In Joo; Kim, Yong Ki; Kim, Seong Jang; Jun, Sung Min; Kim, Bum Soo

    2009-01-01

    The purpose of this study was to evaluate if short-term serum thyroglobulin (Tg) elevation after radioiodine administration can predict successful radioiodine remnant ablation (RRA) and whether comparable RRA effectiveness is exhibited between a group administered with recombinant human thyrotropin (rhTSH) and a group experiencing thyroid hormone withdrawal (THW), in preparation for RRA. A retrospective chart review was performed on 39 patients in the rhTSH group and 46 patients in the THW group. They were treated for differentiated thyroid carcinoma by total or near total thyroidectomy, and referred for RRA between 2003 and 2006 (the rhTSH group) and between January and June of 2006 (the THW group). They were assessed for serum Tg levels just before I-131 administration (TgD0), reassessed 9 days later (TgD9), and again 6-12 months later. RRA was successful in 64 (37 from the THW group and 27 from the rhTSH group) of the total 85 patients. The success rates of RRA had no statistically significant differences between the two groups. In both groups, TgD9/TgD0 values were significantly higher in the RRA success group (the rhTSH group; P=0.03, the THW group; P=0.04). By combining cutoff values of TgD0 and TgD9/TgD0, the successful RRA value was determined to be 96.7% (29/30) with TgD0≤5.28 ng/mL and TgD9/TgD0>4.37 in both groups (the rhTSH group; 100% (16/16), the THW group; 92.9% (13/14)). Using logistic multivariate analysis, only TgD0 was independently associated with successful RRA. We may predict successful ablation by evaluating short-term serum Tg elevation after I-131 administration for RRA, in both rhTSH and THW patients

  5. Lethality Index 2008-2014: Less shootings, same lethality, more opacity

    Directory of Open Access Journals (Sweden)

    Carlos Silva Forné

    2017-11-01

    Full Text Available This article evaluates the use of lethal force by Mexican federal security forces during shootings with presumed members of organized crime from 2008-2014. The authors use official data and press reports on deaths and wounded in shootings to construct indicators such as the number of dead civilians over the number of dead officials from the federal security forces and the number of dead civilians over the number of wounded civilians. In a context where certain factors that contribute to an excessive use of force become more common, the results of the study show a growing use of lethal force. This raises questions over the possible excessive use of lethal force as a normal or systematic practice. The study also shows a growing context of opacity in the information available to evaluate the use of lethal force and the general lack of a legal framework to regulate the use of lethal force in Mexico.

  6. Differences in 3D dose distributions due to calculation method of voxel S-values and the influence of image blurring in SPECT

    International Nuclear Information System (INIS)

    Pacilio, Massimiliano; Basile, Chiara; Amato, Ernesto; Lanconelli, Nico; Torres, Leonel Alberto; Perez, Marco Coca; Gil, Alex Vergara; Botta, Francesca; Ferrari, Mahila; Cremonesi, Marta; Diaz, Nestor Cornejo; Fernández, María; Lassmann, Michael

    2015-01-01

    This study compares 3D dose distributions obtained with voxel S values (VSVs) for soft tissue, calculated by several methods at their current state-of-the-art, varying the degree of image blurring. The methods were: 1) convolution of Dose Point Kernel (DPK) for water, using a scaling factor method; 2) an analytical model (AM), fitting the deposited energy as a function of the source-target distance; 3) a rescaling method (RSM) based on a set of high-resolution VSVs for each isotope; 4) local energy deposition (LED). VSVs calculated by direct Monte Carlo simulations were assumed as reference. Dose distributions were calculated considering spheroidal clusters with various sizes (251, 1237 and 4139 voxels of 3 mm size), uniformly filled with 131 I, 177 Lu, 188 Re or 90 Y. The activity distributions were blurred with Gaussian filters of various widths (6, 8 and 12 mm). Moreover, 3D-dosimetry was performed for 10 treatments with 90 Y derivatives. Cumulative Dose Volume Histograms (cDVHs) were compared, studying the differences in D 95% , D 50% or D max (ΔD 95% , ΔD 50% and ΔD max ) and dose profiles. For unblurred spheroidal clusters, ΔD 95% , ΔD 50% and ΔD max were mostly within some percents, slightly higher for 177 Lu with DPK (8%) and RSM (12%) and considerably higher for LED (ΔD 95% up to 59%). Increasing the blurring, differences decreased and also LED yielded very similar results, but D 95% and D 50% underestimations between 30–60% and 15–50%, respectively (with respect to 3D-dosimetry with unblurred distributions), were evidenced. Also for clinical images (affected by blurring as well), cDVHs differences for most methods were within few percents, except for slightly higher differences with LED, and almost systematic for dose profiles with DPK (−1.2%), AM (−3.0%) and RSM (4.5%), whereas showed an oscillating trend with LED. The major concern for 3D-dosimetry on clinical SPECT images is more strongly represented by image blurring than by

  7. Predictive values of urine paraquat concentration, dose of poison, arterial blood lactate and APACHE II score in the prognosis of patients with acute paraquat poisoning.

    Science.gov (United States)

    Liu, Xiao-Wei; Ma, Tao; Li, Lu-Lu; Qu, Bo; Liu, Zhi

    2017-07-01

    The present study investigated the predictive values of urine paraquat (PQ) concentration, dose of poison, arterial blood lactate and Acute Physiology and Chronic Health Evaluation (APACHE) II score in the prognosis of patients with acute PQ poisoning. A total of 194 patients with acute PQ poisoning, hospitalized between April 2012 and January 2014 at the First Affiliated Hospital of P.R. China Medical University (Shenyang, China), were selected and divided into survival and mortality groups. Logistic regression analysis, receiver operator characteristic (ROC) curve analysis and Kaplan-Meier curve were applied to evaluate the values of urine paraquat (PQ) concentration, dose of poison, arterial blood lactate and (APACHE) II score for predicting the prognosis of patients with acute PQ poisoning. Initial urine PQ concentration (C0), dose of poison, arterial blood lactate and APACHE II score of patients in the mortality group were significantly higher compared with the survival group (all Ppoison and arterial blood lactate correlated with mortality risk of acute PQ poisoning (all Ppoison, arterial blood lactate and APACHE II score in predicting the mortality of patients within 28 days were 0.921, 0.887, 0.808 and 0.648, respectively. The AUC of C0 for predicting early and delayed mortality were 0.890 and 0.764, respectively. The AUC values of urine paraquat concentration the day after poisoning (Csec) and the rebound rate of urine paraquat concentration in predicting the mortality of patients within 28 days were 0.919 and 0.805, respectively. The 28-day survival rate of patients with C0 ≤32.2 µg/ml (42/71; 59.2%) was significantly higher when compared with patients with C0 >32.2 µg/ml (38/123; 30.9%). These results suggest that the initial urine PQ concentration may be the optimal index for predicting the prognosis of patients with acute PQ poisoning. Additionally, dose of poison, arterial blood lactate, Csec and rebound rate also have referential significance.

  8. Preliminary results of an attempt to predict over apron occupational exposure of cardiologists from cardiac fluoroscopy procedures based on DAP (dose area product) values.

    Science.gov (United States)

    Toossi, Mohammad Taghi Bahreyni; Mehrpouyan, Mohammad; Nademi, Hossein; Fardid, Reza

    2015-03-01

    This study is an effort to propose a mathematical relation between the occupational exposure measured by a dosimeter worn on a lead apron in the chest region of a cardiologist and the dose area product (DAP) recorded by a meter attached to the X-ray tube. We aimed to determine factors by which DAP values attributed to patient exposure could be converted to the over-apron entrance surface air kerma incurred by cardiologists during an angiographic procedure. A Rando phantom representing a patient was exposed by an X-ray tube from 77 pre-defined directions. DAP value for each exposure angle was recorded. Cardiologist exposure was measured by a Radcal ionization chamber 10X5-180 positioned on a second phantom representing the physician. The exposure conversion factor was determined as the quotient of over apron exposure by DAP value. To verify the validity of this method, the over-apron exposure of a cardiologist was measured using the ionization chamber while performing coronary angiography procedures on 45 patients weighing on average 75 ± 5 kg. DAP values for the corresponding procedures were also obtained. Conversion factors obtained from phantom exposure were applied to the patient DAP values to calculate physician exposure. Mathematical analysis of our results leads us to conclude that a linear relationship exists between two sets of data: (a) cardiologist exposure measured directly by Radcal & DAP values recorded by the X-ray machine system (R (2) = 0.88), (b) specialist measured and estimated exposure derived from DAP values (R (2) = 0.91). The results demonstrate that cardiologist occupational exposure can be derived from patient data accurately.

  9. Soluble factor(s) from bone marrow cells can rescue lethally irradiated mice by protecting endogenous hematopoietic stem cells.

    Science.gov (United States)

    Zhao, Yi; Zhan, Yuxia; Burke, Kathleen A; Anderson, W French

    2005-04-01

    Ionizing radiation-induced myeloablation can be rescued via bone marrow transplantation (BMT) or administration of cytokines if given within 2 hours after radiation exposure. There is no evidence for the existence of soluble factors that can rescue an animal after a lethal dose of radiation when administered several hours postradiation. We established a system that could test the possibility for the existence of soluble factors that could be used more than 2 hours postirradiation to rescue animals. Animals with an implanted TheraCyte immunoisolation device (TID) received lethal-dose radiation and then normal bone marrow Lin- cells were loaded into the device (thereby preventing direct interaction between donor and recipient cells). Animal survival was evaluated and stem cell activity was tested with secondary bone marrow transplantation and flow cytometry analysis. Donor cell gene expression of five antiapoptotic cytokines was examined. Bone marrow Lin- cells rescued lethally irradiated animals via soluble factor(s). Bone marrow cells from the rescued animals can rescue and repopulate secondary lethally irradiated animals. Within the first 6 hours post-lethal-dose radiation, there is no significant change of gene expression of the known radioprotective factors TPO, SCF, IL-3, Flt-3 ligand, and SDF-1. Hematopoietic stem cells can be protected in lethally irradiated animals by soluble factors produced by bone marrow Lin- cells.

  10. Predictive value of pyramidal lobe, percentage thyroid uptake and age for ablation outcome after 15 mCi fixed dose of radioiodine-131 in Graves’ disease

    International Nuclear Information System (INIS)

    Zaman, Maseeh uz; Fatima, Nosheen; Zaman, Unaiza; Sajjad, Zafar; Zaman, Areeba; Tahseen, Rabia

    2015-01-01

    The purpose was to find out the efficacy of fixed 15 mCi radioactive iodine-131 (RAI) dose and predictive values of various factors for inducing hypothyroidism in Graves’ disease (GD). Retrospective study conducted from January 2012 till August 2014. Patients with GD who had a technetium-99m thyroid scan, thyroid antibodies, received fixed 15 mCi RAI and did follow endocrine clinics for at least 6 months were selected. RAI was considered successful if within 6 months of RAI therapy patients developed hypothyroidism. Of the 370 patients with GD who had RAI during study period, 210 (57%) qualified study criteria. Mean age of patients was 48 ± 15 years with female: male ratio of 69:31, positive thyroid antibodies in 61%, means thyroid uptake of 15.09 ± 11.23%, and presence of pyramidal lobe in 40% of total population. Hypothyroidism was achieved in 161 (77%) patients while 49 (23%) patients failed to achieve it (remained either hyperthyroid or euthyroid on antithyroid medication). Patients who became hypothyroid were significantly younger with higher proportion of presence of thyroid antibodies and pyramidal lobe and lower percentage thyroid uptake than those who failed. Multiple logistic regression analysis revealed that age (odds ratio; OR = 2.074), pyramidal lobe (OR = 3.317), thyroid antibodies (OR = 8.198), and percentage thyroid uptake (OR = 3.043) were found to be significant prognostic risk factors for post-RAI hypothyroidism. Gender was found to have nonsignificant association with the development of hypothyroidism. Receiver operating characteristic analysis revealed age <42 years and thyroid uptake <15% as threshold values for the development of post-RAI hypothyroidism. We conclude that fixed (15 mCi) RAI dose is highly effective in rendering hypothyroidism in patients with GD. Age (≤42 years), thyroid uptake (≤15%) and presence of pyramidal lobe are strong predictors of hypothyroidism and must be considered for selecting optimal RAI dose

  11. A rabies vaccine adjuvanted with saponins from leaves of the soap tree (Quillaja brasiliensis) induces specific immune responses and protects against lethal challenge.

    Science.gov (United States)

    Yendo, Anna Carolina A; de Costa, Fernanda; Cibulski, Samuel P; Teixeira, Thais F; Colling, Luana C; Mastrogiovanni, Mauricio; Soulé, Silvia; Roehe, Paulo M; Gosmann, Grace; Ferreira, Fernando A; Fett-Neto, Arthur G

    2016-04-29

    Quillaja brasiliensis (Quillajaceae) is a saponin producing species native from southern Brazil and Uruguay. Its saponins are remarkably similar to those of Q. saponaria, which provides most of the saponins used as immunoadjuvants in vaccines. The immunostimulating capacities of aqueous extract (AE) and purified saponin fraction (QB-90) obtained from leaves of Q. brasiliensis were favorably comparable to those of a commercial saponin-based adjuvant preparation (Quil-A) in experimental vaccines against bovine herpesvirus type 1 and 5, poliovirus and bovine viral diarrhea virus in mice model. Herein, the immunogenicity and protection efficacy of rabies vaccines adjuvanted with Q. brasiliensis AE and its saponin fractions were compared with vaccines adjuvanted with either commercial Quil-A or Alum. Mice were vaccinated with one or two doses (on days 0 and 14) of one of the different vaccines and serum levels of total IgG, IgG1 and IgG2a were quantified over time. A challenge experiment with a lethal dose of rabies virus was carried out with the formulations. Viral RNA detection in the brain of mice was performed by qPCR, and RNA copy-numbers were quantified using a standard curve of in vitro transcribed RNA. All Q. brasiliensis saponin-adjuvanted vaccines significantly enhanced levels of specific IgG isotypes when compared with the no adjuvant group (P ≤ 0.05). Overall, one or two doses of saponin-based vaccine were efficient to protect against the lethal rabies exposure. Both AE and saponin fractions from Q. brasiliensis leaves proved potent immunological adjuvants in vaccines against a lethal challenge with a major livestock pathogen, hence confirming their value as competitive or complementary sustainable alternatives to saponins of Q. saponaria. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Interaction of radiation, Dihydroxyanthraquinone, and Adriamycin on the induction of acute lethality in mice

    International Nuclear Information System (INIS)

    Kimler, B.F.; Cox, G.G.; Reddy, E.K.

    1984-01-01

    The acute lethality induced by combinations of radiation, Dihydroxyanthraquinone (DHAQ), and Adriamycin (ADR) was investigated in mice. Whole-body irradiation produced acute lethality, with an LD-50/30 of approximately 6.5 Gy. ADR and DHAQ produced LD-50/30's of 14 and 4 mg/kg, respectively. When 10 mg/kg doses were fractionated into 5 x 2 mg/kg daily doses, both drugs were equally or more efficient at producing mortality, 90% by day 30. When 4 Gy radiation was combined with 5 mg/kg ADR or 5 mg/kg DHAQ, a response no greater than that produced by drug alone was obtained. However, when 5 mg/kg ADR was administered concomitantly with 5 mg/kg DHAQ, there was a less-than-additive induction of lethality, resulting in only 21% mortality by day 20. ADR and DHAQ (at doses of 5 mg/kg) were combined but with a 1 day interval between drugs, the protective effect was lost and animals died earlier than after either agent alone. At present, no definite explanation is available for this unusual protective effect of ADR against acute lethality induced by DHAQ

  13. Marked bengal pink. A dynamic test using marking doses; its value in jaundice diagnosis; Rose bengale marque. Epreuve dynamique a doses tracantes; sa valeur dans le diagnostic des icteres

    Energy Technology Data Exchange (ETDEWEB)

    Kellershohn, C; Desgrez, A [Commissariat a l' Energie Atomique, Service Frederic Joliot, Service de Biologie, Saclay (France).Centre d' Etudes Nucleaires; Caroli, J [Hopital Saint Antoine, 75 - Paris (France); Delaloye, B [Lausanne (Switzerland)

    1961-07-01

    The authors do a historic calling back of the differential study of jaundices thanks to the semi logarithmic gradients of expurgation of bromine sulphone-phthalein and thanks to the time of appearance of this material in the bile collected by duodenal tubing. They sum up likewise the foreign works which lead to take the place of this test, the outside count at the level of the head, the liver, and the abdomen after intravenous injection of a running dose of marked Rose Bengal. They specify the technical conditions of this test and report an experience which corroborate its value, its accuracy and the interest of its using in the different types of jaundices (hepatitis and obstructive types). (author) [French] Les auteurs font un rappel historique de l'etude differentielle des icteres grace aux pentes semi-logarithmiques d'epuration de la bromesulfonephtaleine et grace au temps d'apparition de cette substance dans la bile recueillie par tubage duodenal. Ils resument egalement les travaux etrangers qui tendent a substituer a cette epreuve le comptage externe au niveau de la tete, du foie et de l'abdomen, apres injection intraveineuse d'une dose tracante de rose bengale marque. Ils precisent les conditions techniques de cette epreuve et rapportent une experience qui confirme sa valeur, son exactitude et l'interet de son utilisation dans les differentes categories d'icteres par hepatite et par obstruction. (auteur)

  14. Marked bengal pink. A dynamic test using marking doses; its value in jaundice diagnosis; Rose bengale marque. Epreuve dynamique a doses tracantes; sa valeur dans le diagnostic des icteres

    Energy Technology Data Exchange (ETDEWEB)

    Kellershohn, C.; Desgrez, A. [Commissariat a l' Energie Atomique, Service Frederic Joliot, Service de Biologie, Saclay (France).Centre d' Etudes Nucleaires; Caroli, J. [Hopital Saint Antoine, 75 - Paris (France); Delaloye, B. [Lausanne (Switzerland)

    1961-07-01

    The authors do a historic calling back of the differential study of jaundices thanks to the semi logarithmic gradients of expurgation of bromine sulphone-phthalein and thanks to the time of appearance of this material in the bile collected by duodenal tubing. They sum up likewise the foreign works which lead to take the place of this test, the outside count at the level of the head, the liver, and the abdomen after intravenous injection of a running dose of marked Rose Bengal. They specify the technical conditions of this test and report an experience which corroborate its value, its accuracy and the interest of its using in the different types of jaundices (hepatitis and obstructive types). (author) [French] Les auteurs font un rappel historique de l'etude differentielle des icteres grace aux pentes semi-logarithmiques d'epuration de la bromesulfonephtaleine et grace au temps d'apparition de cette substance dans la bile recueillie par tubage duodenal. Ils resument egalement les travaux etrangers qui tendent a substituer a cette epreuve le comptage externe au niveau de la tete, du foie et de l'abdomen, apres injection intraveineuse d'une dose tracante de rose bengale marque. Ils precisent les conditions techniques de cette epreuve et rapportent une experience qui confirme sa valeur, son exactitude et l'interet de son utilisation dans les differentes categories d'icteres par hepatite et par obstruction. (auteur)

  15. Extra lethal damage due to residual incompletely repaired sublethal damage in hyperfractionated and continuous radiation treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.; van de Geijn, J.; Goffman, T. (ROB, DCT, NCI, NIH, Bethesda, Maryland 20892 (US))

    1991-05-01

    In the conventional linear--quadratic model of single-dose response, the {alpha} and {beta} terms reflect lethal damage created {ital during} the delivery of a dose, from two different presumed molecular processes, one linear with dose, the other quadratic. With the conventional one-fraction-per-day (or less) regimens, the sublethal damage (SLD), presumably repairing exponentially over time, is essentially completely fixed by the time of the next dose of radiation. If this assumption is true, the effects of subsequent fractions of radiation should be independent, that is, there should be little, if any, reversible damage left from previous fractions, at the time of the next dose. For multiple daily fractions, or for the limiting case, continuous radiation, this simplification may overlook damaged cells that have had insufficient time for repair. A generalized method is presented for accounting for extra lethal damage (ELD) arising from such residual SLD for hyperfractionation and continuous irradiation schemes. It may help to predict differences in toxicity and tumor control, if any, obtained with unconventional'' treatment regimens. A key element in the present model is the finite size and the dynamic character of the pool of sublethal damage. Besides creating the usual linear and quadratic components of lethal damage, each new fraction converts a certain fraction of the existing SLD into ELD, and creates some new SLD.

  16. Extra lethal damage due to residual incompletely repaired sublethal damage in hyperfractionated and continuous radiation treatment

    International Nuclear Information System (INIS)

    Chen, J.; van de Geijn, J.; Goffman, T.

    1991-01-01

    In the conventional linear--quadratic model of single-dose response, the α and β terms reflect lethal damage created during the delivery of a dose, from two different presumed molecular processes, one linear with dose, the other quadratic. With the conventional one-fraction-per-day (or less) regimens, the sublethal damage (SLD), presumably repairing exponentially over time, is essentially completely fixed by the time of the next dose of radiation. If this assumption is true, the effects of subsequent fractions of radiation should be independent, that is, there should be little, if any, reversible damage left from previous fractions, at the time of the next dose. For multiple daily fractions, or for the limiting case, continuous radiation, this simplification may overlook damaged cells that have had insufficient time for repair. A generalized method is presented for accounting for extra lethal damage (ELD) arising from such residual SLD for hyperfractionation and continuous irradiation schemes. It may help to predict differences in toxicity and tumor control, if any, obtained with ''unconventional'' treatment regimens. A key element in the present model is the finite size and the dynamic character of the pool of sublethal damage. Besides creating the usual linear and quadratic components of lethal damage, each new fraction converts a certain fraction of the existing SLD into ELD, and creates some new SLD

  17. Lethal mutation of internal irradiation brown planthopper (Nilaparvita lugens Stal)

    International Nuclear Information System (INIS)

    Wahid, R.A.

    1988-01-01

    The moulting IVth of BPH nympha were irradiated internally with radiophosphorous 32-P 1 uCi/ml, 10 uCi/ml, 50 uCi/ml, 100 uCi/ml, and 500 uCi/ml concentrations respectivelly. An observation was carried out to determines heredity of hopper sterilities from the mating groups of R male x N female, R male x R female, and N male x R female. The 32-P concentration below of 50 uCi/ml seemed to be the substerile dose, however, the dominant lethal mutation has been visually shown by R male x R female F1 mating group. The hereditary lines of F1, F2, F3, and F4 of the hopper sterilities wich were indicated by the nympha hatch ability have some significant correlations (r1= -0.77, r2= -0.92, r3= -0.93 and r4= -0.85). Thus, the resesif lethal mutations visually showed by F3 and F4 from all of the 100 uCi/ml and 50 uCi/ml treated groups. (author). 10 refs, 2 figs, 2 tabs

  18. Genetics Home Reference: Amish lethal microcephaly

    Science.gov (United States)

    ... 1 in 500 newborns in the Old Order Amish population of Pennsylvania. It has not been found outside this population. Related Information What information about a genetic condition can statistics provide? Why are some genetic ... gene cause Amish lethal microcephaly . The SLC25A19 gene provides instructions for ...

  19. The evolution of lethal intergroup violence

    OpenAIRE

    Kelly, Raymond C.

    2005-01-01

    Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

  20. The evolution of lethal intergroup violence.

    Science.gov (United States)

    Kelly, Raymond C

    2005-10-25

    Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

  1. A new lethal sclerosing bone dysplasia

    International Nuclear Information System (INIS)

    Kingston, H.M.; Freeman, J.S.; Hall, C.M.

    1991-01-01

    A neonate is described with a lethal sclerosing bone dysplasia associated with prenatal fractures and craniofacial abnormalities including microcephaly, exophthalmos, hypoplastic nose and mid-face, small jaw and nodular hyperplasia of the gums. Parental consanguinity suggests that an autosomal recessive mutation is the likely aetiology. (orig.)

  2. Tolerization with BLP down-regulates HMGB1 a critical mediator of sepsis-related lethality.

    LENUS (Irish Health Repository)

    Coffey, J Calvin

    2012-02-03

    Tolerization with bacterial lipoprotein (BLP) affords a significant survival benefit in sepsis. Given that high mobility group box protein-1 (HMGB1) is a recognized mediator of sepsis-related lethality, we determined if tolerization with BLP leads to alterations in HMGB1. In vitro, BLP tolerization led to a reduction in HMGB1 gene transcription. This was mirrored at the protein level, as HMGB1 protein expression and release were reduced significantly in BLP-tolerized human THP-1 monocytic cells. BLP tolerance in vivo led to a highly significant, long-term survival benefit following challenge with lethal dose BLP in C57BL\\/6 mice. This was associated with an attenuation of HMGB1 release into the circulation, as evidenced by negligible serum HMGB1 levels in BLP-tolerized mice. Moreover, HMGB1 levels in peritoneal macrophages from BLP-tolerized mice were reduced significantly. Hence, tolerization with BLP leads to a down-regulation of HMGB1 protein synthesis and release. The improved survival associated with BLP tolerance could thus be explained by a reduction in HMGB1, were the latter associated with lethality in BLP-related sepsis. In testing this hypothesis, it was noted that neutralization of HMGB1, using anti-HMGB1 antibodies, abrogated BLP-associated lethality almost completely. To conclude, tolerization with BLP leads to a down-regulation of HMGB1, thus offering a novel means of targeting the latter. HMGB1 is also a mediator of lethality in BLP-related sepsis.

  3. Restoring efficiency of hemopoietic cell transplantation in a mouse lethally irradiated by a total exposure to X rays

    International Nuclear Information System (INIS)

    Doria, Gino

    1959-10-01

    This research thesis reports the study of possibility of treatments (or restoration) of a mouse which has been submitted to a lethal dose of X rays. More particularly, the author compared the restoring efficiency of bone marrow and fetal liver injected in a mouse which had been lethally irradiated by a total exposure to X rays. He also studied the functional status of the hemopoietic graft, and the emergence of the secondary disease in mice which had been as well lethally irradiated and then restored by injection of bone marrow and fetal liver. The author then addressed the influence of the induction of immune tolerance of the host with respect to the donor on the survival of a mouse lethally irradiated and restored by homologue bone marrow [fr

  4. Dominant lethal and ovarian effects of plutonium-239 in female mice

    International Nuclear Information System (INIS)

    Searle, A.G.; Beechey, C.V.; Green, D.; Howells, G.R.

    1982-01-01

    (C3H x 101)F 1 female mice were injected intravenously with 239 Pu in trisodium citrate, then mated in pairs to strain CBA males, to test for dominant lethality. In the first experiment 10μCi kg -1 and in the second 20μCi kg -1 body mass was injected. Matings were after 6 days in the first experiment (estimated ovarian absorbed dose of 0.1 Gy) and after 3,6 or 12 weeks in the second (estimated ovarian doses of 1.11, 2.45 and 5.91 Gy respectively). No evidence of dominant lethal induction was found in the first experiment, but in the second there was a significant increase over controls in pre-implantation loss in all three series. Post-implantation lethality increased significantly (by 12%) only after 12 weeks' exposure. With the 6- and 12-week exposures (especially the latter) luteal counts fell, fewer females becoming pregnant than in controls. This is attributed to oocyte killing by the α-particles. Histological and autoradiographic investigations showed a marked reduction in ovarian size and follicular numbers with fission-tracks clustered mainly over the medullary stroma. The preimplantation loss may stem from lowered fertilization of oocytes because of their damage, so that the best measure of dominant lethality is that based on post-implantation death. (author)

  5. The frequency of allelic lethals and complementation maps in natural populations of drosophila melanogaster from Mexico

    Directory of Open Access Journals (Sweden)

    Salceda Victor M.

    2004-01-01

    Full Text Available Departing from a previous study on the genetic loads affecting the second chromosome of Drosophila melanogaster in four natural populations, 171 lethal chromosomes were recovered and maintained as a balanced stocks in the condition Cy L / 1 (l=lethal; of those lethais 24 correspond to population A, 50 to populations B and C and 47 to population D. later on an intra-population allelism test for the four populations was performed for each one. A total of 3807 inter lethal crosses were done yielding a total of i 10 allelic combinations, from them the respective percentage of allelism for each population was calculated and they are as follow: 3.98 % for population A, 1.80 % for population B, 3.67 % for population C and 2.96 % for population D. the observed values for the frequency of allelism in these populations are not significantly different from those reported by other authors in similar studies in natural and/or experimental populations. Beside these values the frequency for singles, doubles, triplets and even quadruplets present in each population were determined, they shown the presence of various complementation maps due to the clustering of few different lethals: also a large complementation map formed by a large cluster involving the presence of 26 different lethals found in population D all of them combined constituting a single unit was found.

  6. Passive dosing of polycyclic aromatic hydrocarbon (PAH) mixtures to terrestrial springtails: linking mixture toxicity to chemical activities, equilibrium lipid concentrations, and toxic units.

    Science.gov (United States)

    Schmidt, Stine N; Holmstrup, Martin; Smith, Kilian E C; Mayer, Philipp

    2013-07-02

    A 7-day mixture toxicity experiment with the terrestrial springtail Folsomia candida was conducted, and the effects were linked to three different mixture exposure parameters. Passive dosing from silicone was applied to tightly control exposure levels and compositions of 12 mixture treatments, containing the polycyclic aromatic hydrocarbons (PAHs) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (∑a), sum equilibrium lipid concentrations (∑C(lipid eq.)), and sum toxic units (∑TU). In each case, the effects of all 12 mixture treatments could be fitted to one sigmoidal exposure-response relationship. The effective lethal chemical activity (La50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid-based exposure parameter yielded an effective lethal concentration (LC(lipid eq 50)) of 133 mmol kg(-1) lipid in good correspondence with the lethal membrane burden for baseline toxicity (40-160 mmol kg(-1) lipid). Finally, the effective lethal toxic unit (LTU50) of 1.20 was rather close to the expected value of 1. Altogether, passive dosing provided tightly controlled mixture exposure in terms of both level and composition, while ∑a, ∑C(lipid eq.), and ∑TU allowed baseline toxicity to be linked to mixture exposure.

  7. Prognostic value of high-dose dobutamine stress magnetic resonance imaging in 1,493 consecutive patients: assessment of myocardial wall motion and perfusion.

    Science.gov (United States)

    Korosoglou, Grigorios; Elhmidi, Yacine; Steen, Henning; Schellberg, Dieter; Riedle, Nina; Ahrens, Johannes; Lehrke, Stephanie; Merten, Constanze; Lossnitzer, Dirk; Radeleff, Jannis; Zugck, Christian; Giannitsis, Evangelos; Katus, Hugo A

    2010-10-05

    This study sought to determine the prognostic value of wall motion and perfusion assessment during high-dose dobutamine stress (DS) cardiac magnetic resonance imaging (MRI) in a large patient cohort. DS-MRI offers the possibility to integrate myocardial perfusion and wall motion analysis in a single examination for the detection of coronary artery disease (CAD). A total of 1,493 consecutive patients with suspected or known CAD underwent DS-MRI, using a standard protocol in a 1.5-T magnetic resonance scanner. Wall motion and perfusion were assessed at baseline and during stress, and outcome data including cardiac death, nonfatal myocardial infarction ("hard events"), and "late" revascularization performed >90 days after the MR scans were collected during a 2 ± 1 year follow-up period. Fifty-three hard events, including 14 cardiac deaths and 39 nonfatal infarctions, occurred during the follow-up period, whereas 85 patients underwent "late" revascularization. Using multivariable regression analysis, an abnormal result for wall motion or perfusion during stress yielded the strongest independent prognostic value for both hard events and late revascularization, clearly surpassing that of clinical and baseline magnetic resonance parameters (for wall motion: adjusted hazard ratio [HR] of 5.9 [95% confidence interval (CI): 2.5 to 13.6] for hard events and of 3.1 [95% CI: 1.7 to 5.6] for late revascularization, and for perfusion: adjusted HR of 5.4 [95% CI: 2.3 to 12.9] for hard events and of 6.2 [95% CI: 3.3 to 11.3] for late revascularization, p < 0.001 for all). DS-MRI can accurately identify patients who are at increased risk for cardiac death and myocardial infarction, separating them from those with normal findings, who have very low risk for future cardiac events. (Prognostic Value of High Dose Dobutamine Stress Magnetic Resonance Imaging; NCT00837005). Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. Lethal neonatal short-limbed dwarfism

    International Nuclear Information System (INIS)

    Kim, Ok Hwa; Yim, Chung Ik; Bahk, Yong Whee

    1986-01-01

    We have detailed our experiences on 6 cases of neonatal lethal short-limbed dwarfism and reviewed the articles. They include, achondrogenesis, thanatophoric dysplasia, asphyxiating thoracic dysplasia, osteogenesis imperfect a congenita, and hypophosphatasia lethals. Five babies were born alive but died soon after birth and one was a stillbirth. The main cause of failure to thrive was respiratory insufficiency. Each case was having quite characteristic radiologic findings, even if the general appearances were similar to the achondroplasts clinically. Precise diagnosis is very important for genetic counselling of the parents and alarm to them the possibility of bone dysplasias to the next offsprings. For this purpose, the radiologists play major role for the correct diagnosis. We stress that when the baby is born with short-limbed dwarfism, whole body radiogram should be taken including lateral view and postmortem radiogram is also very precious.

  9. Lethal neonatal short-limbed dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ok Hwa; Yim, Chung Ik; Bahk, Yong Whee [Catholic Medical College, Seoul (Korea, Republic of)

    1986-02-15

    We have detailed our experiences on 6 cases of neonatal lethal short-limbed dwarfism and reviewed the articles. They include, achondrogenesis, thanatophoric dysplasia, asphyxiating thoracic dysplasia, osteogenesis imperfect a congenita, and hypophosphatasia lethals. Five babies were born alive but died soon after birth and one was a stillbirth. The main cause of failure to thrive was respiratory insufficiency. Each case was having quite characteristic radiologic findings, even if the general appearances were similar to the achondroplasts clinically. Precise diagnosis is very important for genetic counselling of the parents and alarm to them the possibility of bone dysplasias to the next offsprings. For this purpose, the radiologists play major role for the correct diagnosis. We stress that when the baby is born with short-limbed dwarfism, whole body radiogram should be taken including lateral view and postmortem radiogram is also very precious.

  10. Mining of lethal recessive genetic variation in Danish cattle

    DEFF Research Database (Denmark)

    Das, Ashutosh

    2015-01-01

    in fertility. The primary objective of this PhD projekt was to identify recessive lethal gentic variants in the main Danish dairy cattle breed. Holstein-Friesian utilzing next generation sequencing (NGS) data. This study shows a potential for the use of the NGS-based reverse genetic approach in identifying...... lethal or semi-lethal recessive gentic variation...

  11. Lethal midline granuloma syndrome: a diagnostic dilemma

    International Nuclear Information System (INIS)

    Ribeiro, Bruno Niemeyer de Freitas; Bahia, Paulo Roberto Valle; Oliveira, Ana Luiza Vianna Sobral de Magalhaes; Marchon Junior, Joao Luiz

    2012-01-01

    The rare lethal midline granuloma syndrome is difficult to diagnose because of the wide array of related diseases and lack of knowledge by the majority of physicians. In the present report, the authors describe the case of a patient with this disease, caused by squamous cell carcinoma, drawing attention to differential diagnoses and to clinical and radiological findings that may be useful to define the diagnosis. (author)

  12. Lethal Interpersonal Violence in the Middle Pleistocene

    OpenAIRE

    Sala, Nohemi; Arsuaga, Juan Luis; Pantoja-P?rez, Ana; Pablos, Adri?n; Mart?nez, Ignacio; Quam, Rolf M.; G?mez-Olivencia, Asier; Berm?dez de Castro, Jos? Mar?a; Carbonell, Eudald

    2015-01-01

    Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force ...

  13. Lethal midline granuloma syndrome: a diagnostic dilemma

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Bruno Niemeyer de Freitas; Bahia, Paulo Roberto Valle [Radiology, Hospital Universitario Clementino Fraga Filho - Universidade Federal do Rio de Janeiro (HUCFF-UFRJ), Rio de Janeiro, RJ (Brazil); Oliveira, Ana Luiza Vianna Sobral de Magalhaes [Resident of Medical Practice, Hospital Federal da Lagoa, Rio de Janeiro, RJ (Brazil); Marchon Junior, Joao Luiz [Unit of Computed Tomography, Hospital Federal da Lagoa, Rio de Janeiro, RJ (Brazil)

    2012-11-15

    The rare lethal midline granuloma syndrome is difficult to diagnose because of the wide array of related diseases and lack of knowledge by the majority of physicians. In the present report, the authors describe the case of a patient with this disease, caused by squamous cell carcinoma, drawing attention to differential diagnoses and to clinical and radiological findings that may be useful to define the diagnosis. (author)

  14. In vivo toxic and lethal cardiovascular effects of a synthetic polymeric 1,3-dodecylpyridinium salt in rodents

    International Nuclear Information System (INIS)

    Grandic, Marjana; Sepcic, Kristina; Turk, Tom; Juntes, Polona; Frangez, Robert

    2011-01-01

    APS12-2 is one in a series of synthetic analogs of the polymeric alkylpyridinium salts isolated from the marine sponge Reniera sarai. As it is a potential candidate for treating non small cell lung cancer (NSCLC), we have studied its possible toxic and lethal effects in vivo. The median lethal dose (LD 50 ) of APS12-2 in mice was determined to be 11.5 mg/kg. Electrocardiograms, arterial blood pressure and respiratory activity were recorded under general anesthesia in untreated, pharmacologically vagotomized and artificially ventilated rats injected with APS12-2. In one group, the in vivo effects of APS12-2 were studied on nerve-evoked muscle contraction. Administration of APS12-2 at a dose of 8 mg/kg caused a progressive reduction of arterial blood pressure to a mid-circulatory value, accompanied by bradycardia, myocardial ischemia, ventricular extrasystoles, and second degree atrio-ventricular block. Similar electrocardiogram and arterial blood pressure changes caused by APS12-2 (8 mg/kg) were observed in animals pretreated with atropine and in artificially ventilated animals, indicating that hypoxia and cholinergic effects do not play a crucial role in the toxicity of APS12-2. Application of APS12-2 at sublethal doses (4 and 5.5 mg/kg) caused a decrease of arterial blood pressure, followed by an increase slightly above control values. We found that APS12-2 causes lysis of rat erythrocytes in vitro, therefore it is reasonable to expect the same effect in vivo. Indeed, hyperkalemia was observed in the blood of experimental animals. Hyperkalemia probably plays an important role in APS12-2 cardiotoxicity since no evident changes in histopathology of the heart were found. However, acute lesions were observed in the pulmonary vessels of rats after application of 8 mg/kg APS12-2. Predominant effects were dilation of interalveolar blood vessels and lysis of aggregated erythrocytes within their lumina. - Highlights: → LD 50 estimated in mice (11.5 mg/kg) revealed that

  15. Lethal interpersonal violence in the Middle Pleistocene.

    Directory of Open Access Journals (Sweden)

    Nohemi Sala

    Full Text Available Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

  16. Lethal interpersonal violence in the Middle Pleistocene.

    Science.gov (United States)

    Sala, Nohemi; Arsuaga, Juan Luis; Pantoja-Pérez, Ana; Pablos, Adrián; Martínez, Ignacio; Quam, Rolf M; Gómez-Olivencia, Asier; Bermúdez de Castro, José María; Carbonell, Eudald

    2015-01-01

    Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

  17. Low survival of mice following lethal gamma-irradiation after administration of inhibitors of prostaglandin synthesis

    International Nuclear Information System (INIS)

    Hofer, M.; Pospisil, M.; Tkadlecek, L.; Viklicka, S.; Pipalova, I.; Hola, J.

    1992-01-01

    An impairment was observed of the survival of mice subjected to whole-body gamma-irradiation with a lethal dose of 10 Gy and treated with a repeated postirradiation administration of the prostaglandin synthesis inhibitors (PGSIs) indomethacin or diclofenac. Morphological examination of the gastrointestinal tract and estimation of the blood loss into its lumen in animals treated with diclofenac did not show serious damage such as hemorrhages or perforation, but revealed structural injury to the intestinal mucosa indicating inflammatory processes. The lesions found are supposed to be connected with increased intestinal permeability which leads to endotoxin escape from the gut and a subsequent increased mortality rate of irradiated animals. It may be concluded that PGSIs are not suitable for the management of radiation sickness after an exposure to lethal doses of ionizing radiation. (author) 2 tabs., 4 figs., 20 refs

  18. Survival of bone marrow-engrafted mice subsequent to protection from lethal radiation by WR 2721

    International Nuclear Information System (INIS)

    Kinnamon, K.E.; Ketterling, L.L.; Ledney, G.D.; Lorenz, G.B.; Mioduszewski, R.J.; Stampfli, H.F.

    1980-01-01

    For the first time data are presented for animals treated with bone marrow cells after lethal radiation exposure while protected with WR 2721 (the single radioprotective chemical compound with the highest known dose reduction factor). The LD 50 30 (lethal dose to 50% in 30 days) for mice exposed to whole-body 60 Co radiation was elevated from 824 +- 8 rad in unprotected and untreated mice to (a) 1181 +- 33 rad in animals which received syngeneic bone marrow cells after exposure; (b) 1342 +- 27 rad in animals which received WR 2721 before radiation exposure; and (c) 1608 +- 33 rad in animals receiving both the radioprotective agent before exposure and bone marrow engraftment after exposure

  19. Interactive lethal and mutagenic effects of ultraviolet light and bleomycin in yeast: synergism or antagonism?

    Science.gov (United States)

    Lillo, O L; Severgnini, A A; Nunes, E M

    1997-11-01

    The mutagenic interactions of ultraviolet light and bleomycin in haploid populations of Saccharomyces cerevisiae were analyzed. Survival and mutation frequency as a function of different bleomycin concentrations after one conditioning dose of UV radiation were determined. Furthermore, corresponding interaction functions and sensitization factors were calculated. A synergistic interaction between UV light and bleomycin was shown for both lethal and mutagenic events when the cells were in nutrient broth during the treatments. Conversely, the interaction between UV light and bleomycin was antagonistic when the cells were in deionized water during the treatment. The magnitude of lethal and mutagenic interactions depends on dose, and thus presumably on the number of lesions. The observed interactions between UV light and bleomycin suggest that the mechanism that is most likely involved is the induction of repair systems with different error probabilities during the delay of cell division.

  20. Dominant lethal mutations and histological changes produced in mouse oocytes by gamma irradiation

    International Nuclear Information System (INIS)

    Vyglenov, A.; Baev, I.; Rupova, I.; Kusheva, R.

    1976-01-01

    Mouse female were exposed to a total dose of 500 or 1000 rad 137 Cs gamma rays delivered at 0.01 rad/min. Effects were scored at 1, 5, 7, and 10 weeks after cessation of treatment. Histologically, ovaria in the 500 rad group showed a decrease up to 11% in follicle numbers as compared to controls; with the prolongation of the time after exposure, a further fall in follicle numbers is observed. In the 1000 rad group, depopulation of ovaria was complete. With the 500 rad dose, total dominant lethality was found to be increased for any of the time intervals between radiation exposure and conception; postimplantation dominant lethality was comparatively low, with similar scores between the weeks investigated. (author)

  1. On different types of hereditable changes in the viability of Amoeba protens cells x-irradiated with varying doses

    International Nuclear Information System (INIS)

    Bychkovskaya, I.B.; Ochinskaya, G.K.; Erokhina, G.M.

    1976-01-01

    Qualitatively different types of cells lethality have been observed in the posterity of amoebae irradiated with doses ranging from 0.5 to 40 kR and from 60 to 120 kR. At doses of 0.5 to 40 kR, a certain part of cells in a population dies, and the effect is characterized by stability and independency of a radiation dose, hereditable radiation damage of all the cells in the population, and by the fact that it might be caused not only by a derect action of radiation but also by a preirradiated culture medium. Higher doses (60 to 120 kR) cause a more drastic but sell stable effect. Depending on a dose value, a varying percentage of cells has shown the effect not being caused by the action of the preirradiated medium. The data obtained indicate that there are different mechanisms of hereditable radiation damages to cells caused by varying radiation doses

  2. Potentiation of radiation lethality by Topotecan, a Topoisomerase I inhibitor

    International Nuclear Information System (INIS)

    Lamond, J.P.; Kinsella, T.J.; Boothman, D.A.

    1995-01-01

    Purpose/Objective: Topotecan is a water soluble Topoisomerase I (Topo I) inhibitor that has demonstrated antineoplastic activity in phase I/II trials of solid tumors (such as non-small cell lung, small cell lung, ovarian, esophageal and head and neck primaries) and leukemias. We sought to determine (1) if Topotecan potentiated the lethal effects of ionizing radiation, and (2) the characteristics of the synergistic effect. Materials and Methods: Human radioresistant melanoma (U1-Mel) and glioma (D54) cells were grown in Dulbecco's modified Eagle's medium (DME) with 10% fetal calf serum (FCS) until confluence-arrest. Cells were x-irradiated (0-700 cGy) and exposed to various Topotecan concentrations (2-100μM), either before (for 4 hours), during, or after (for 4 hours) irradiation. Appropriate controls were also performed. Survival was determined via colony forming assays. Survival curves were normalized to correct for drug cytotoxicities and variations in initial viable cells plated. In another set of experiments, U1-Mel cells were exposed to 10 μM Topotecan either before, during or after 400 cGy, as described above. A modification of the SDS and KCl assay was used to quantify Topo I-DNA complexes via glass fiber filter binding. All experiments were performed at least 7 times in duplicate. Results: Potentiation of radiation lethality was seen in the U1-Mel and D54 cell lines. The synergistic effects were (1) dependent on drug concentration, with lethality enhancement and minimal drug lethality alone in the 2-10 μM range (2) dependent on timing, with synergy present only when the drug was present at the time of, or shortly after irradiation, and (3) irreversible, with inhibition of potential lethal damage repair (PLDR). The dose enhancement ratios (DER) for 4 μM Topotecan in the U1-Mel cells was 1.7 - 2.4, depending on the survival endpoints that were used. The DER for 2 μM Topotecan in D54 cells was 3.0 - 4.0. The U1-Mel cells that were exposed to Topotecan

  3. Female Rats are Less Susceptible during Puberty to Lethal Effects of Percutaneous Exposure to VX

    Science.gov (United States)

    2015-12-17

    lethal dose determination for percutaneous exposure to soman and VX in guinea pigs and the effectiveness of decontamination with M291 SDK or SANDIA...di-isopropylamino) ethyl] methyl phosphonthioate) through pig , human and guinea pig skin in vitro, Toxicol. In Vitro 20 (2006) 1532–1536. [6] R... production and transepidermal water loss [TEWL]) change with age [3,14,15]. As reviewed in Ref. [28], the barrier function of the stratum corneum is

  4. Verification of CTDI and Dlp values for a head tomography reported by the manufacturers of the CT scanners, using a CT dose profiler probe, a head phantom and a piranha electrometer

    International Nuclear Information System (INIS)

    Castillo C, E.; Garcia F, I. B.; Garcia H, J.; Roman L, S.; Salmeron C, O.

    2015-10-01

    The extensive use of Computed Tomography (CT) and the associated increase in patient dose calls for an accurate dose evaluation technique. The CT contributes up to 70% of the total dose given to patients during X-ray examinations. The rapid advancements in CT technology are placing new demands on the methods and equipment that are used for quality assurance. The wide beam widths found in CT scanners with multiple beam apertures make it impossible to use existing CT ionization chambers to measure the total dose given to the patient. Using a standard 10 cm CT ionization chamber may result in inaccurate measurements due to underestimation of the dose profile for wide beams. The use a CT dose profiler based on solid-state technology and the Piranha electrometer from RTI electronics provides a potential solution to the arising concerns over patient dose. This study intend to evaluate the feasibility and accuracy of CT Dose Index (CTDI) and Dose Length Product (Dlp) values for a head tomography reported by the manufacturers of the CT scanners at each study. (Author)

  5. Verification of CTDI and Dlp values for a head tomography reported by the manufacturers of the CT scanners, using a CT dose profiler probe, a head phantom and a piranha electrometer

    Energy Technology Data Exchange (ETDEWEB)

    Castillo C, E.; Garcia F, I. B.; Garcia H, J.; Roman L, S. [Servicios de Salud de Michoacan, Centro Estatal de Atencion Oncologica, Gertrudis Bocanegra No. 300, Col. Cuauhtemoc, 58020 Morelia, Michoacan (Mexico); Salmeron C, O., E-mail: edithcastillocorona@gmail.com [Servicios de Salud de Michoacan, Hospital General Dr. Miguel Silva, Isidro Huarte s/n, Centro Historico, 58000 Morelia, Michoacan (Mexico)

    2015-10-15

    The extensive use of Computed Tomography (CT) and the associated increase in patient dose calls for an accurate dose evaluation technique. The CT contributes up to 70% of the total dose given to patients during X-ray examinations. The rapid advancements in CT technology are placing new demands on the methods and equipment that are used for quality assurance. The wide beam widths found in CT scanners with multiple beam apertures make it impossible to use existing CT ionization chambers to measure the total dose given to the patient. Using a standard 10 cm CT ionization chamber may result in inaccurate measurements due to underestimation of the dose profile for wide beams. The use a CT dose profiler based on solid-state technology and the Piranha electrometer from RTI electronics provides a potential solution to the arising concerns over patient dose. This study intend to evaluate the feasibility and accuracy of CT Dose Index (CTDI) and Dose Length Product (Dlp) values for a head tomography reported by the manufacturers of the CT scanners at each study. (Author)

  6. Value of Single-Dose Contrast-Enhanced Magnetic Resonance Angiography Versus Intraarterial Digital Subtraction Angiography in Therapy Indications in Abdominal and Iliac Arteries

    International Nuclear Information System (INIS)

    Schaefer, Philipp J.; Schaefer, Fritz K. W.; Mueller-Huelsbeck, Stefan; Both, Markus; Heller, Martin; Jahnke, Thomas

    2007-01-01

    The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committee was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30 o , field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses ≥50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies

  7. Comparison of PSA value at last follow-up of patients who underwent low-dose rate brachytherapy and intensity-modulated radiation therapy for prostate cancer.

    Science.gov (United States)

    Tanaka, Nobumichi; Asakawa, Isao; Nakai, Yasushi; Miyake, Makito; Anai, Satoshi; Fujii, Tomomi; Hasegawa, Masatoshi; Konishi, Noboru; Fujimoto, Kiyohide

    2017-08-25

    To compare the PSA value at the last follow-up of patients who underwent prostate low-dose rate brachytherapy (LDR-BT) with that of patients who underwent intensity-modulated radiation therapy (IMRT). A total of 610 prostate cancer patients (cT1c-3bN0M0) were enrolled, and 445 of them underwent LDR-BT, while 165 received IMRT (74-76 Gy). The median follow-up period of these two groups was 75 months (LDR-BT) and 78 months (IMRT), respectively. We also evaluated the biochemical recurrence (BCR)-free rate using two definitions (Phoenix definition and PSA ≥ 0.2 ng/mL). The percentage of patients who achieved PSA LDR-BT group and 49.7% in the IMRT group (p LDR-BT group and 32.1% in the IMRT group (p LDR-BT groups was 89.5 and 95.0% (p LDR-BT groups, respectively (p LDR-BT was significantly lower than that of IMRT, and this result was particularly marked in patients with a normal testosterone level at the last follow-up.

  8. Estimation of Median Lethal Concentration of Three Isolates of Beauveria bassiana for Control of Megacopta cribraria (Heteroptera: Plataspidae) Bioassayed on Solid Lygus spp. Diet.

    Science.gov (United States)

    Portilla, Maribel; Jones, Walker; Perera, Omaththage; Seiter, Nick; Greene, Jeremy; Luttrell, Randall

    2016-06-30

    The kudzu bug, Megacopta cribraria (F.), is an urban nuisance and significant agricultural pest. The median lethal concentrations of three strains of Beauveria bassiana (Balsamo), including the Mississippi Delta native strain (NI8) isolated from Lygus lineolaris (Palisot de Beauvois), the commercial strain BotaniGard(®) (GHA) (Victor, NY, USA), and the B. bassiana strain isolated from M. cribraria (KUDSC), were estimated on kudzu bug adults. A technique developed to evaluate B. bassiana against L. lineolaris was used. Younger adults (eight days after collection) were treated with NI8 and GHA and older adult (50 days after collection) were treated with NI8, GHA and KUDSC. Higher concentrations (n × 10⁶, n × 10⁷) of NI8 and GHA caused kudzu bug mortality two days after treatment in younger adults and similar concentrations of NI8, GHA, and KUDSC caused mortality one day after treatment in older adults. Lower concentrations (n × 10⁴, n × 10⁵) were not significantly different in mortality between strains. LS50 values of the KUDSC were significantly lower than NI8 and GHA values in older adults. This is the first available information on median lethal concentration of B. bassiana on kudzu bug adults bioassayed on artificial diet. It was determined that B. bassiana (KUDSC and NI8) are highly effective for young adults at very low doses (LC50 1.98-4.98 viable spores per mm²).

  9. Evaluating the lethal and pre-lethal effects of a range of fungi against adult Anopheles stephensi mosquitoes

    Directory of Open Access Journals (Sweden)

    Blanford Simon

    2012-11-01

    Full Text Available Abstract Background Insecticide resistance is seriously undermining efforts to eliminate malaria. In response, research on alternatives to the use of chemical insecticides against adult mosquito vectors has been increasing. Fungal entomopathogens formulated as biopesticides have received much attention and have shown considerable potential. This research has necessarily focused on relatively few fungal isolates in order to ‘prove concept’. Further, most attention has been paid to examining fungal virulence (lethality and not the other properties of fungal infection that might also contribute to reducing transmission potential. Here, a range of fungal isolates were screened to examine variation in virulence and how this relates to additional pre-lethal reductions in feeding propensity. Methods The Asian malaria vector, Anopheles stephensi was exposed to 17 different isolates of entomopathogenic fungi belonging to species of Beauveria bassiana, Metarhizium anisopliae, Metarhizium acridum and Isaria farinosus. Each isolate was applied to a test substrate at a standard dose rate of 1×109 spores ml-1 and the mosquitoes exposed for six hours. Subsequently the insects were removed to mesh cages where survival was monitored over the next 14 days. During this incubation period the mosquitoes’ propensity to feed was assayed for each isolate by offering a feeding stimulant at the side of the cage and recording the number probing. Results and conclusions Fungal isolates showed a range of virulence to A. stephensi with some causing >80% mortality within 7 days, while others caused little increase in mortality relative to controls over the study period. Similarly, some isolates had a large impact on feeding propensity, causing >50% pre-lethal reductions in feeding rate, whereas other isolates had very little impact. There was clear correlation between fungal virulence and feeding reduction with virulence explaining nearly 70% of the variation in

  10. Lethal congenital contracture syndrome (LCCS) and other lethal arthrogryposes in Finland--an epidemiological study.

    Science.gov (United States)

    Pakkasjärvi, Niklas; Ritvanen, Annukka; Herva, Riitta; Peltonen, Leena; Kestilä, Marjo; Ignatius, Jaakko

    2006-09-01

    Arthrogryposis multiplex congenita is a heterogeneous group of disorders characterized by multiple contractures with an estimated frequency of 1 in 3,000 births. With improving diagnostic methods, increasing numbers of fetuses with arthrogryposis are found. The pathogenetic mechanisms are relatively well known but the epidemiology and genetics of the prenatally lethal forms of arthrogryposis are less well known. In this study we collected all cases of a multiple contractures diagnosed in Finland during 1987-2002 including live born infants, stillbirths, and terminated pregnancies. Ninety-two cases of 214 suffered intrauterine demise (68 selective pregnancy terminations and 24 stillbirths) and 58 died in infancy. In 141 out of these cases the diagnosis could be included within lethal arthrogryposes, with a prevalence of 1 in 6,985 (1.43/10,000) births. Of these, 59 had spinal cord pathology at autopsy and thus were of neurogenic origin. Thirty-nine cases had lethal congenital contracture syndrome (LCCS) clinically characterized by total immobility of the fetus at all ultrasound examinations (12 weeks or later), multiple joint contractures in both upper and lower limbs, hydrops, and fetal death before the 32nd week of pregnancy. LCCS is noted as a unique Finnish disorder with a prevalence of 1 in 25,250 (0.40/10,000) births and is a major cause of lethal arthrogryposis in Finland.

  11. Suicide Intent and Accurate Expectations of Lethality: Predictors of Medical Lethality of Suicide Attempts

    Science.gov (United States)

    Brown, Gregory K.; Henriques, Gregg R.; Sosdjan, Daniella; Beck, Aaron T.

    2004-01-01

    The degree of intent to commit suicide and the severity of self-injury were examined in individuals (N = 180) who had recently attempted suicide. Although a minimal association was found between the degree of suicide intent and the degree of lethality of the attempt, the accuracy of expectations about the likelihood of dying was found to moderate…

  12. Potentially lethal damage and its repair

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1989-01-01

    Two forms termed fast-and slow-potentially lethal lethal damage (PLD) are introduced and discussed. The effect on the survival of x-irradiated Chinese hamster cells (V79) of two different post-treatments is examined in plateau- and in log-phases of growth. The postirradiation treatments used : a) incubation in hypertonic solution, and b) incubation in conditioned medium obtained from plateau-phase. Similar reduction in survival was caused by postirradiation treatment with hypertonic phosphate buffered saline, and similar increased in survival was effected by treatment in conditioned medium in plateau- and in log-phases cells. However, repair of PLD sensitive to hypertonic treatment was faster (half time, 5-10 min)(f-PLD repair) and independent from the repair of PLD (half time, 1-2 hour)(s-PLD repair) observed in conditioned medium. The results indicate the induction of two forms of PLD by radiation. Induction of both PLD was found to decrease with increasing LET of the radiation used. Identification of the molecular processes underlying repair and fixation of PLD is a task of particular interest, since it may allow replacement of a phenomenological definition with a molecular definition. Evidence is reviewed indicating the DNA double strand breaks (directly or indirectly induced) may be the DNA lesions underlying PLD. (author)

  13. Lethal domestic violence in eastern North Carolina.

    Science.gov (United States)

    Gilliland, M G; Spence, P R; Spence, R L

    2000-01-01

    Strategies for preventing domestic violence can be tailored to a particular geographic or socioeconomic area if the patterns of domestic violence in the area are known. National statistics, although widely available, may not be applicable to a specific region. We reviewed homicide deaths in Eastern North Carolina between 1978 and 1999 to identify patterns in this rural area. Approximately 20% of the homicide deaths in eastern North Carolina are caused by intimate partners. Women accounted for 53% of the victims in 1976, similar to national figures but not rising to 72% as seen nationally in 1998. Latinos are an increasing presence in the area, but had only one recorded episode of lethal violence against an intimate partner. Gunshots accounted for most of the deaths (59% in men, 72% in women). Knowledge of such patterns can assist in selecting prevention strategies for this particular area. Over the last 25 years increasing attention has been devoted to domestic violence (DV), initially defined as abuse committed against a spouse, former spouse, fiancée, boy- or girlfriend, or cohabitant. As time has passed, the definition has been broadened to include other family members--elders, children, and siblings. The Centers for Disease Control and Prevention (CDC) now uses the term "intimate partner violence" for intentional emotional or physical abuse inflicted by a spouse, ex-spouse, a present or former boy- or girlfriend, or date. For the purposes of this paper, we consider DV interchangeable with intimate partner violence. There has been a national concern that abusive events are under-reported. The National Crime Victimization Survey, an anonymous household survey, indicated nearly 1 million incidents of non-lethal intimate partner violence per year between 1992 and 1996. The number decreased from 1.1 million in 1993 to 840,000 in 1996. Attempts to validate such data for a given geographic area often require subjects to violate anonymity--this may account for lower

  14. Lethal effect of glucose load on malignant cells

    International Nuclear Information System (INIS)

    Shmakova, N.L.; Yarmonenko, S.P.; Kozubek, S.

    1987-01-01

    Ehrlich ascites tumor (EAT) cells were treated with glucose load under anoxic conditions (for 15 or 60 min) and/or with γ radiation (20 Gy). The efficiency of the treatment was judged from the tumorigenic activity of EAT cell inocula. The markedly increased efficiency of the combined treatment of EAT cells using glucose load in anoxia and γ radiation is due to the additive action of both agents. The glucose load in anoxia leads to extensive desintegration of tumor cells. Further, the lethal effect of various pH values on EAT cells was investigated. Different pH values were obtained by means of both glucose load and phosphate buffers. The effect was investigated by determining the tumorigenic activity of EAT cells tested in vivo in mice and by determining the radiosensitivity of treated EAT cells. The results allowed us to conclude that the same values of pH lead to the same effect on EAT cells independently of the way by which the given pH value was reached. (author). 5 figs., 2 tabs., 12 refs

  15. The lethal effect of longwave ultraviolet light and PUVA. An analysis based upon human mesenchymal cells in vitro

    International Nuclear Information System (INIS)

    Jongh, G. de; Bergers, M.; Boezeman, J.B.M.; Verhagen, A.R.; Mier, P.D.

    1984-01-01

    The lethal effect of UVA and PUVA radiation was studied in cultures of fresh and mature monocytes. UVA radiation alone was shown to possess a lethal effect at doses which are attained in the dermis in vivo. The synergistic action of 8-methoxypsoralen and UVA radiation predominated in PUVA radiation, but again a residual effect of UVA alone was demonstrated mathematically. Mature cells were less sensitive than fresh monocytes. The results indicate that a monolayer culture of non-dividing, mesenchymal cells offers considerable advantages over in vivo systems as a model for the study of phototoxicity. (author)

  16. Estimation of mutation rates induced by large doses of gamma, proton and neutron irradiation of the X-chromosome of the nematode Panagrellus redivivus

    International Nuclear Information System (INIS)

    Denich, K.T.R.; Samoiloff, M.R.

    1984-01-01

    The radiation-resistant free-living nematode Panagrellus redivivus was used to study mutation rates in oocytes, following gamma, proton and neutron irradiation in the dose range 45-225 grays. γ-Radiation produced approximately 0.001 lethal X-chromosomes per gray over the range tested. Proton or neutron irradiation produced approximately 0.003 lethal X-chromosomes per gray at lower doses, with the mutation rate dropping to 0.001 lethal X-chromosome per gray at the higher doses. These results suggest a dose-dependent mutation-repair system. Cell lethality was also examined. γ-Radiation produced the greatest amount of cell lethality at all doses, while neutron irradiation had no cell lethal effect at any of the doses examined. (orig.)

  17. The role of pH in lethal effect of glucose load malignant cells

    International Nuclear Information System (INIS)

    Shmakova, N.L.; Yarmonenko, S.P.; Laser, K.; Fomenkova, T.E.; Kozubek, S.; Korogodin, V.I.

    1985-01-01

    The lethal effect of variuos pH values on Erlich ascites tumour (EAT) calls has been investigated. Different pH values were obtained by means of both glucose load and phosphate buffers. The effect has been investigated by observing cell death in vitro, determining cancerogenity of EAT cells and determining their radiosensitivity. The results of all methods enabled us to conclude that the same values of pH lead to the same effect on EAT cells independently of the way by which the given pH value was reached. The lethal effect markedly increased when the value of pH was lower than 5.6. It is concluded that the basis of the mechanism of glucose load lethal effect is their ''self-acidisation''. The measurement of pH in tumours is proposed as a basic test for determining the suitability of the use of hyperglycemia in clinics and for comparison of the efficiency of various modes of treatment

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

    International Nuclear Information System (INIS)

    Tallarico, Lenita de Freitas

    2003-01-01

    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 60 Co 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

  19. Computed tomography of lethal medline granuloma

    International Nuclear Information System (INIS)

    Lee, Ho Suk; Kim, Tae Ho; Suh, Kyung Jin; Kim, Tae Hun; Kim, Yong Joo; Kang, Duk Sik

    1991-01-01

    In order to clarify the CT findings of lethal midline granuloma (LMG) diagnosed clinically or histopathologically, the authors retrospectively analyzed 12 patients who were seen at Kyungpook National University Hospital from February 1985 to August 1989. CT showed nasal mucosal thickening and / or soft tissue mass (9 case), spreading of the lesions along the facial subcutaneous fat plane (8 cases), invasion into the paranasal sinuses (5 cases), bone destruction (5 cases), nasopharyngeal mass lesion (2 cases), and extension of the lesion into the infratemporal fossa (1 case). In spite of the fact that CT does not make definitive diagnosis of LMG, it permits evaluation of the extent of the lesion, detection of the combined lesion, differential diagnosis, and close monitoring of its evolution under treatment

  20. Ants defend aphids against lethal disease

    Science.gov (United States)

    Nielsen, Charlotte; Agrawal, Anurag A.; Hajek, Ann E.

    2010-01-01

    Social insects defend their own colonies and some species also protect their mutualist partners. In mutualisms with aphids, ants typically feed on honeydew produced by aphids and, in turn guard and shelter aphid colonies from insect natural enemies. Here we report that Formica podzolica ants tending milkweed aphids, Aphis asclepiadis, protect aphid colonies from lethal fungal infections caused by an obligate aphid pathogen, Pandora neoaphidis. In field experiments, bodies of fungal-killed aphids were quickly removed from ant-tended aphid colonies. Ant workers were also able to detect infective conidia on the cuticle of living aphids and responded by either removing or grooming these aphids. Our results extend the long-standing view of ants as mutualists and protectors of aphids by demonstrating focused sanitizing and quarantining behaviour that may lead to reduced disease transmission in aphid colonies. PMID:19923138

  1. Tityus serrulatus venom--A lethal cocktail.

    Science.gov (United States)

    Pucca, Manuela Berto; Cerni, Felipe Augusto; Pinheiro Junior, Ernesto Lopes; Bordon, Karla de Castro Figueiredo; Amorim, Fernanda Gobbi; Cordeiro, Francielle Almeida; Longhim, Heloisa Tavoni; Cremonez, Caroline Marroni; Oliveira, Guilherme Honda; Arantes, Eliane Candiani

    2015-12-15

    Tityus serrulatus (Ts) is the main scorpion species of medical importance in Brazil. Ts venom is composed of several compounds such as mucus, inorganic salts, lipids, amines, nucleotides, enzymes, kallikrein inhibitor, natriuretic peptide, proteins with high molecular mass, peptides, free amino acids and neurotoxins. Neurotoxins are considered the most responsible for the envenoming syndrome due to their pharmacological action on ion channels such as voltage-gated sodium (Nav) and potassium (Kv) channels. The major goal of this review is to present important advances in Ts envenoming research, correlating both the crude Ts venom and isolated toxins with alterations observed in all human systems. The most remarkable event lies in the Ts induced massive releasing of neurotransmitters influencing, directly or indirectly, the entire body. Ts venom proved to extremely affect nervous and muscular systems, to modulate the immune system, to induce cardiac disorders, to cause pulmonary edema, to decrease urinary flow and to alter endocrine, exocrine, reproductive, integumentary, skeletal and digestive functions. Therefore, Ts venom possesses toxins affecting all anatomic systems, making it a lethal cocktail. However, its low lethality may be due to the low venom mass injected, to the different venom compositions, the body characteristics and health conditions of the victim and the local of Ts sting. Furthermore, we also described the different treatments employed during envenoming cases. In particular, throughout the review, an effort will be made to provide information from an extensive documented studies concerning Ts venom in vitro, in animals and in humans (a total of 151 references). Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. A linear-quadratic model of cell survival considering both sublethal and potentially lethal radiation damage

    International Nuclear Information System (INIS)

    Rutz, H.P.; Coucke, P.A.; Mirimanoff, R.O.

    1991-01-01

    The authors assessed the dose-dependence of repair of potentially lethal damage in Chinese hamster ovary cells x-irradiated in vitro. The recovery ratio (RR) by which survival (SF) of the irradiated cells was enhanced increased exponentially with a linear and a quadratic component namely ζ and ψ: RR=exp(ζD+ψD 2 ). Survival of irradiated cells can thus be expressed by a combined linear-quadratic model considering 4 variables, namely α and β for the capacity of the cells to accumulate sublethal damage, and ζ and ψ for their capacity to repair potentially lethal damage: SF=exp((ζ-α)D+ (ψ-β)D 2 ). author. 26 refs.; 1 fig.; 1 tab

  3. X-ray induced dominant lethal mutations in mature and immature oocytes of guinea-pigs and golden hamsters

    International Nuclear Information System (INIS)

    Cox, B.D.; Lyon, M.F.

    1975-01-01

    The induction of dominant lethal mutations by doses of 100-400 rad X-rays in oocytes of the guinea-pig and golden hamster was studied using criteria of embryonic mortality. For both species higher yields were obtained from mature than from immature oocytes. Data on fertility indicated that in the golden hamster immature oocytes were more sensitive to killing by X-rays than mature oocytes but that the converse was true in the guinea-pig. The dose-response relationship for mutation to dominant lethals in pre-ovulatory oocytes of guinea-pigs and golden hamsters was linear, both when based on pre- and post-implantation loss only. The rate per unit dose was higher for the golden hamster, and the old golden hamsters were possibly slightly more sensitive than young ones

  4. 35S induced dominant lethals in immature Oocytes in mice

    International Nuclear Information System (INIS)

    Satyanarayana Reddy, K.; Reddy, P.; Reddy, O.S.

    1976-01-01

    CBA female mice were injected intraperitoneally with a dose of 20 μCi of sulphur-35 on 15.5 day post conception. Another group of pregnant mice injected with normal saline was kept as control. The pregnant females were allowed to litter and the mothers were separated from their offspring 4 weeks after littering. Eight weeks after treatment i.e. at the age of 22-24 weeks, the treated mothers were mated to control C 3 H/He males. The vaginal plugs were checked everyday morning and those mated were separated. The pregnants were killed on 14th day of gestation. The uterine contents were searched for live and dead embryos and the ovaries for corpora lutea. The pre, post and total loses were calculated in the treated females and compared with those of control. The statistical tests performed indicated that all losses are significant. The results indicate that 35 S can induce chromosomal breaks in immature oocytes and lead to the induction of dominant lethals. (author)

  5. Galantamine is a novel post-exposure therapeutic against lethal VX challenge

    International Nuclear Information System (INIS)

    Hilmas, Corey J.; Poole, Melissa J.; Finneran, Kathryn; Clark, Matthew G.; Williams, Patrick T.

    2009-01-01

    The ability of galantamine hydrobromide (GAL HBr) treatment to antagonize O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX)-induced lethality, impairment of muscle tension, and electroencephalographic (EEG) changes was assessed in guinea pigs. Guinea pigs were challenged with 16.8 μg/kg VX (2LD50). One min after challenge, animals were administered 0.5 mg/kg atropine sulfate (ATR) and 25 mg/kg pyridine-2-aldoxime methochloride (2-PAM). In addition, guinea pigs were given 0, 1, 2, 4, 8 or 10 mg/kg GAL as a post-exposure treatment immediately prior to ATR and 2-PAM. Animals were either monitored for 24-h survival, scheduled for electroencephalography (EEG) recording, or euthanized 60 min later for measurement of indirectly-elicited muscle tension in the hemidiaphragm. Post-exposure GAL therapy produced a dose-dependent increase in survival from lethal VX challenge. Optimal clinical benefits were observed in the presence of 10 mg/kg GAL, which led to 100% survival of VX-challenged guinea pigs. Based on muscle physiology studies, GAL post-exposure treatment protected the guinea pig diaphragm, the major effector muscle of respiration, from fatigue, tetanic fade, and muscular paralysis. Protection against the paralyzing effects of VX was dose-dependent. In EEG studies, GAL did not alter seizure onset for all doses tested. At the highest dose tested (10 mg/kg), GAL decreased seizure duration when administered as a post-exposure treatment 1 min after VX. GAL also reduced the high correlation associated between seizure activity and lethality after 2LD50 VX challenge. GAL may have additional benefits both centrally and peripherally that are unrelated to its established mechanism as a reversible acetylcholinesterase inhibitor (AChEI).

  6. Dose dependency of the frequency of micronucleated binucleated clone cells and of division related median clone sizes difference. Pt. 2

    International Nuclear Information System (INIS)

    Hagemann, G,; Kreczik, A.; Treichel, M.

    1996-01-01

    Following irradiation of the progenitor cells the clone growth of CHO cells decreases as a result of cell losses. Lethally acting expressions of micronuclei are produced by heritable lethal mutations. The dependency of the frequency of micronucleated binucleated clone cells and of the median clone sizes difference on the radiation dose was measured and compared to non-irradiated controls. Using the cytokinesis-block-micronucleus-method binucleated cells with micronuclei were counted as ratio of all binucleated cells within a clone size distribution. This ratio (shortened: micronucleus yield) was determined for all clone size distributions, which had been exposed to different irradiation doses and incubation times. The micronucleus yields were compared to the corresponding median clone sizes differences. The micronucleus yield is linearly dependent on the dose and is independent of the incubation time. The same holds true for the division related median clone sizes difference, which as a result is also linearly dependent on the micronucleus yield. Due to the inevitably errors of the cell count of micronucleated binucleated cells, an automatic measurement of the median clone sizes differences is the preferred method for evaluation of cellular radiation sensitivity for heritable lethal mutations. This value should always be determined in addition, if clone survival fractions are used as predictive test because it allows for an estimation of the remission probability of surviving cells. (orig.) [de

  7. Is It Better to Enter a Volume CT Dose Index Value before or after Scan Range Adjustment for Radiation Dose Optimization of Pediatric Cardiothoracic CT with Tube Current Modulation?

    Science.gov (United States)

    2018-01-01

    Objective To determine whether the body size-adapted volume computed tomography (CT) dose index (CTDvol) in pediatric cardiothoracic CT with tube current modulation is better to be entered before or after scan range adjustment for radiation dose optimization. Materials and Methods In 83 patients, cardiothoracic CT with tube current modulation was performed with the body size-adapted CTDIvol entered after (group 1, n = 42) or before (group 2, n = 41) scan range adjustment. Patient-related, radiation dose, and image quality parameters were compared and correlated between the two groups. Results The CTDIvol after the CT scan in group 1 was significantly higher than that in group 2 (1.7 ± 0.1 mGy vs. 1.4 ± 0.3 mGy; p Hounsfield units [HU] vs. 4.5 ± 0.7 HU) and image quality (1.5 ± 0.6 vs. 1.5 ± 0.6) showed no significant differences between the two (p > 0.05). In both groups, all patient-related parameters, except body density, showed positive correlations (r = 0.49–0.94; p 0.05) in group 2. Conclusion In pediatric cardiothoracic CT with tube current modulation, the CTDIvol entered before scan range adjustment provides a significant dose reduction (18%) with comparable image quality compared with that entered after scan range adjustment.

  8. Methods for the determination of the man-Sievert monetary value

    International Nuclear Information System (INIS)

    Lombard, J.

    1986-03-01

    To estimate the efficiency of radiological protection systems we have to compare the cost involved in putting each system into operation (cost of protection) to the collective dose that can thus be avoided. This comparison is facilitated if a man-Sievert monetary value is available. The man-Sievert value can be estimated from various detriments than can be attributed to this unitary exposure: whether there are lethal or non-lethal somatic effects, genetic effects and psycho-social effects. ICRP recommends, in its publication 37, to break down the cost of radiological detriment Y into two parts. The first part, Y1=αS, corresponds to the somatic and genetic effects; the second part, Y2=β ΣN j f(Hj), corresponds to the relevant effects of psycho-social considerations. This breakdown leads to the definition of two man-Sievert value components: α, which reflects somatic and genetic detriments; and β, which reflects the psycho-social effects. Several different methods can be used to determine α and β. Here, we will analyse the following: the a priori evaluation based on the Value of Human Life (VHL) or the costs of repair (for non-lethal effects); the a priori evaluation based on the loss of life expectancy; the evaluation based on what an individual would agree to give up to reduce the risk associated to a man Sievert-dose; the evaluation based on the expenses effectively incurred in the past to reduce the risk associated to a man-Sievert dose [fr

  9. Presence of virus neutralizing antibodies in cerebral spinal fluid correlates with non-lethal rabies in dogs.

    Directory of Open Access Journals (Sweden)

    Clement W Gnanadurai

    Full Text Available Rabies is traditionally considered a uniformly fatal disease after onset of clinical manifestations. However, increasing evidence indicates that non-lethal infection as well as recovery from flaccid paralysis and encephalitis occurs in laboratory animals as well as humans.Non-lethal rabies infection in dogs experimentally infected with wild type dog rabies virus (RABV, wt DRV-Mexico correlates with the presence of high level of virus neutralizing antibodies (VNA in the cerebral spinal fluid (CSF and mild immune cell accumulation in the central nervous system (CNS. By contrast, dogs that succumbed to rabies showed only little or no VNA in the serum or in the CSF and severe inflammation in the CNS. Dogs vaccinated with a rabies vaccine showed no clinical signs of rabies and survived challenge with a lethal dose of wild-type DRV. VNA was detected in the serum, but not in the CSF of immunized dogs. Thus the presence of VNA is critical for inhibiting virus spread within the CNS and eventually clearing the virus from the CNS.Non-lethal infection with wt RABV correlates with the presence of VNA in the CNS. Therefore production of VNA within the CNS or invasion of VNA from the periphery into the CNS via compromised blood-brain barrier is important for clearing the virus infection from CNS, thereby preventing an otherwise lethal rabies virus infection.

  10. Measurement of oxygen enhancement ratio for sub-lethal region using saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Nairy, Rajesha K.; Anjaria, K.B.; Bhat, Nagesh N.; Chaurasia, Rajesh K.; Balakrishnan, Sreedevi; Yerol, Narayana

    2013-01-01

    Oxygen is one of the best known modifiers of radiation sensitivity and the biological effects is greater in the presence of oxygen, and significant modifying effect will be observed only for low LET radiations. The reduced oxygen availability is sensed which trigger homeostatic responses, which impact on virtually all areas of biology and medicine. Failure to achieve complete response following radiotherapy of large tumors is attributed to the presence of radio-resistant hypoxic cells, therefore clarifying the mechanism of the oxygen effect is important. In the present study, a mutant type diploid yeast strain, Saccharomyces cerevisiae D7 was used to study Oxygen Enhancement Ratio (OER) using 60 Co gamma radiation. Cells were washed thrice by centrifugation (2000 g for 5 min) and re-suspended to a cell concentration of 1x108 cells mL-1 in a sterile polypropylene vial for irradiation (sub-lethal dose range, 0-100 Gy). Hypoxic conditions were achieved by incubating the cells in airtight vials at 30℃ for 30 min prior to irradiation. The gene conversion and back mutation analysis were carried out according to the standard protocol. Gene conversion is the radio-sensitive biological endpoint, that can be studied in Saccharomyces cerevisiae D7 yeast cells at trp locus in tryptophan (Trp- medium) deficient medium. The dose response relation at euoxic and hypoxic condition in sub-lethal doses are found to be linear and is represented by Y (Euoxic) = (6.54±0.102) D with R2=0.999 and for hypoxic condition Y(Hypoxic) = (3.346±0.033) D with R2=0.996. The OER can be calculated by dividing the euoxic slope with hypoxic slope, and is 1.95. Back mutation, which is a result of reversion of Isoleucine auxotrophs to prototrophs gives very good information at sub-lethal doses. The dose response relation between back mutated cells and radiation doses at Euoxic and hypoxic condition can be represented as Y(Euoxic) = (2.85±0.126) D with R2= 0.976 and for hypoxic condition Y

  11. Dose sculpting with generalized equivalent uniform dose

    International Nuclear Information System (INIS)

    Wu Qiuwen; Djajaputra, David; Liu, Helen H.; Dong Lei; Mohan, Radhe; Wu, Yan

    2005-01-01

    With intensity-modulated radiotherapy (IMRT), a variety of user-defined dose distribution can be produced using inverse planning. The generalized equivalent uniform dose (gEUD) has been used in IMRT optimization as an alternative objective function to the conventional dose-volume-based criteria. The purpose of this study was to investigate the effectiveness of gEUD optimization to fine tune the dose distributions of IMRT plans. We analyzed the effect of gEUD-based optimization parameters on plan quality. The objective was to determine whether dose distribution to selected structures could be improved using gEUD optimization without adversely altering the doses delivered to other structures, as in sculpting. We hypothesized that by carefully defining gEUD parameters (EUD 0 and n) based on the current dose distributions, the optimization system could be instructed to search for alternative solutions in the neighborhood, and we could maintain the dose distributions for structures already satisfactory and improve dose for structures that need enhancement. We started with an already acceptable IMRT plan optimized with any objective function. The dose distribution was analyzed first. For structures that dose should not be changed, a higher value of n was used and EUD 0 was set slightly higher/lower than the EUD value at the current dose distribution for critical structures/targets. For structures that needed improvement in dose, a higher to medium value of n was used, and EUD 0 was set to the EUD value or slightly lower/higher for the critical structure/target at the current dose distribution. We evaluated this method in one clinical case each of head and neck, lung and prostate cancer. Dose volume histograms, isodose distributions, and relevant tolerance doses for critical structures were used for the assessment. We found that by adjusting gEUD optimization parameters, the dose distribution could be improved with only a few iterations. A larger value of n could lead to

  12. Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida

    NARCIS (Netherlands)

    Rico, Andreu; Sabater, Consuelo; Castillo, María Ángeles

    2016-01-01

    The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure

  13. Lethal endomyocarditis caused by chronic "Krokodil" intoxication.

    Science.gov (United States)

    Sorrentino, Antonella; Trotta, Silvia; Colucci, Anna Pia; Aventaggiato, Lucia; Marzullo, Andrea; Solarino, Biagio

    2018-03-19

    "Krokodil" is a home-made opioid drug obtained by synthesizing desomorphine from codeine and combining it with other low-cost additives. Initially introduced in the former Soviet countries, it was then imported to Western Europe as a heroin substitute. To our knowledge, this is the first report of an Italian case of lethal krokodil abuse, that occurred in a 39-year-old man, who died suddenly after transportation to the Emergency Department (ED) for hyperthermia associated with sweating, dyspnoea and tachycardia. Post-mortem examination revealed extensive necrotic ulcerative lesions on the forearms, and autopsy showed a hypertrophic heart with ample endocardial vegetation on the aortic valve and patency of the foramen ovale. Histopathological examination of the heart showed ulcero-vegetative lesions of the aortic valve with an abscess on the annulus and extension to the periaortic adipose tissue, as well as diffuse myocardial interstitial inflammatory neutrophilic infiltrates. Toxicological analysis demonstrated a desomorphine metabolite in urine. On the basis of all these findings the cause of death was ruled to be congestive heart failure caused by endocarditis and myocarditis, correlated with chronic abuse of krokodil.

  14. Tumor clone dynamics in lethal prostate cancer.

    Science.gov (United States)

    Carreira, Suzanne; Romanel, Alessandro; Goodall, Jane; Grist, Emily; Ferraldeschi, Roberta; Miranda, Susana; Prandi, Davide; Lorente, David; Frenel, Jean-Sebastien; Pezaro, Carmel; Omlin, Aurelius; Rodrigues, Daniel Nava; Flohr, Penelope; Tunariu, Nina; S de Bono, Johann; Demichelis, Francesca; Attard, Gerhardt

    2014-09-17

    It is unclear whether a single clone metastasizes and remains dominant over the course of lethal prostate cancer. We describe the clonal architectural heterogeneity at different stages of disease progression by sequencing serial plasma and tumor samples from 16 ERG-positive patients. By characterizing the clonality of commonly occurring deletions at 21q22, 8p21, and 10q23, we identified multiple independent clones in metastatic disease that are differentially represented in tissue and circulation. To exemplify the clinical utility of our studies, we then showed a temporal association between clinical progression and emergence of androgen receptor (AR) mutations activated by glucocorticoids in about 20% of patients progressing on abiraterone and prednisolone or dexamethasone. Resistant clones showed a complex dynamic with temporal and spatial heterogeneity, suggesting distinct mechanisms of resistance at different sites that emerged and regressed depending on treatment selection pressure. This introduces a management paradigm requiring sequential monitoring of advanced prostate cancer patients with plasma and tumor biopsies to ensure early discontinuation of agents when they become potential disease drivers. Copyright © 2014, American Association for the Advancement of Science.

  15. Human cooperation by lethal group competition.

    Science.gov (United States)

    Egas, Martijn; Kats, Ralph; van der Sar, Xander; Reuben, Ernesto; Sabelis, Maurice W

    2013-01-01

    Why humans are prone to cooperate puzzles biologists, psychologists and economists alike. Between-group conflict has been hypothesized to drive within-group cooperation. However, such conflicts did not have lasting effects in laboratory experiments, because they were about luxury goods, not needed for survival ("looting"). Here, we find within-group cooperation to last when between-group conflict is implemented as "all-out war" (eliminating the weakest groups). Human subjects invested in helping group members to avoid having the lowest collective pay-off, whereas they failed to cooperate in control treatments with random group elimination or with no subdivision in groups. When the game was repeated, experience was found to promote helping. Thus, not within-group interactions alone, not random group elimination, but pay-off-dependent group elimination was found to drive within-group cooperation in our experiment. We suggest that some forms of human cooperation are maintained by multi-level selection: reciprocity within groups and lethal competition among groups acting together.

  16. Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival.

    Science.gov (United States)

    Tinkum, Kelsey L; Stemler, Kristina M; White, Lynn S; Loza, Andrew J; Jeter-Jones, Sabrina; Michalski, Basia M; Kuzmicki, Catherine; Pless, Robert; Stappenbeck, Thaddeus S; Piwnica-Worms, David; Piwnica-Worms, Helen

    2015-12-22

    Short-term fasting protects mice from lethal doses of chemotherapy through undetermined mechanisms. Herein, we demonstrate that fasting preserves small intestinal (SI) architecture by maintaining SI stem cell viability and SI barrier function following exposure to high-dose etoposide. Nearly all SI stem cells were lost in fed mice, whereas fasting promoted sufficient SI stem cell survival to preserve SI integrity after etoposide treatment. Lineage tracing demonstrated that multiple SI stem cell populations, marked by Lgr5, Bmi1, or HopX expression, contributed to fasting-induced survival. DNA repair and DNA damage response genes were elevated in SI stem/progenitor cells of fasted etoposide-treated mice, which importantly correlated with faster resolution of DNA double-strand breaks and less apoptosis. Thus, fasting preserved SI stem cell viability as well as SI architecture and barrier function suggesting that fasting may reduce host toxicity in patients undergoing dose intensive chemotherapy.

  17. Modeling response of species to microcontaminants: comparative ecotoxicology by (sub)lethal body burdens as a function of species size and partition ratio of chemicals.

    Science.gov (United States)

    Hendriks, A J

    1995-11-01

    A model was designed and calibrated with accumulation data to calculate the internal concentrations of microcontaminants in organisms as a function of a few constants and variables. The main factors are the exposure time, the external exposure concentration, the partition ratio of the compound, and the size of the taxon concerned. The model was applied to calculate the lethal and sublethal body burdens of several priority compounds and some major taxa. Estimations were generally confirmed at the order of magnitude level by measured residues and applied doses if available. According to the estimations, most priority compounds chosen were critical for most taxa above internal concentrations of 0.1 mmol.kg-1 wet wt. Trichloromethane, 1,2,4-trichlorobenzene, and hexachlorobenzene were lethal above this level only, whereas other organic microcontaminants affected at least some taxa at lower body burdens. The log(Kow) of the organic compounds ranged from 2.0 to 7.0. Keeping in mind that bioconcentration and -magnification ratios for metals may be quite variable, the lowest critical residues estimated were just below the value of 0.1 mmol.kg-1 wet wt. Here, external concentrations encountered in natural habitats seem to be a promising tool for predictive comparative ecotoxicology. The critical body burdens for plants and invertebrates may have been overestimated due to uncertainty about the parameters. Among the different taxa, however, the fish families chosen (Salmonidae and Cyprinidae) seem to be most sensitive to most compounds. Internal response concentrations of the herbicide atrazine were the lowest in micro- and macrophytes, whereas parathion affected invertebrates at low levels. The database that provided the external response concentrations was also consulted to estimate so-called extrapolation or safety factors. On average, long-term no effect concentrations in water are estimated to be about 10-30 times below short-term median lethal levels. In general, short

  18. Feasibility Study of Using Gemstone Spectral Imaging (GSI) and Adaptive Statistical Iterative Reconstruction (ASIR) for Reducing Radiation and Iodine Contrast Dose in Abdominal CT Patients with High BMI Values.

    Science.gov (United States)

    Zhu, Zheng; Zhao, Xin-ming; Zhao, Yan-feng; Wang, Xiao-yi; Zhou, Chun-wu

    2015-01-01

    To prospectively investigate the effect of using Gemstone Spectral Imaging (GSI) and adaptive statistical iterative reconstruction (ASIR) for reducing radiation and iodine contrast dose in abdominal CT patients with high BMI values. 26 patients (weight > 65kg and BMI ≥ 22) underwent abdominal CT using GSI mode with 300mgI/kg contrast material as study group (group A). Another 21 patients (weight ≤ 65kg and BMI ≥ 22) were scanned with a conventional 120 kVp tube voltage for noise index (NI) of 11 with 450mgI/kg contrast material as control group (group B). GSI images were reconstructed at 60keV with 50%ASIR and the conventional 120kVp images were reconstructed with FBP reconstruction. The CT values, standard deviation (SD), signal-noise-ratio (SNR), contrast-noise-ratio (CNR) of 26 landmarks were quantitatively measured and image quality qualitatively assessed using statistical analysis. As for the quantitative analysis, the difference of CNR between groups A and B was all significant except for the mesenteric vein. The SNR in group A was higher than B except the mesenteric artery and splenic artery. As for the qualitative analysis, all images had diagnostic quality and the agreement for image quality assessment between the reviewers was substantial (kappa = 0.684). CT dose index (CTDI) values for non-enhanced, arterial phase and portal phase in group A were decreased by 49.04%, 40.51% and 40.54% compared with group B (P = 0.000), respectively. The total dose and the injection rate for the contrast material were reduced by 14.40% and 14.95% in A compared with B. The use of GSI and ASIR provides similar enhancement in vessels and image quality with reduced radiation dose and contrast dose, compared with the use of conventional scan protocol.

  19. Feasibility Study of Using Gemstone Spectral Imaging (GSI and Adaptive Statistical Iterative Reconstruction (ASIR for Reducing Radiation and Iodine Contrast Dose in Abdominal CT Patients with High BMI Values.

    Directory of Open Access Journals (Sweden)

    Zheng Zhu

    Full Text Available To prospectively investigate the effect of using Gemstone Spectral Imaging (GSI and adaptive statistical iterative reconstruction (ASIR for reducing radiation and iodine contrast dose in abdominal CT patients with high BMI values.26 patients (weight > 65kg and BMI ≥ 22 underwent abdominal CT using GSI mode with 300mgI/kg contrast material as study group (group A. Another 21 patients (weight ≤ 65kg and BMI ≥ 22 were scanned with a conventional 120 kVp tube voltage for noise index (NI of 11 with 450mgI/kg contrast material as control group (group B. GSI images were reconstructed at 60keV with 50%ASIR and the conventional 120kVp images were reconstructed with FBP reconstruction. The CT values, standard deviation (SD, signal-noise-ratio (SNR, contrast-noise-ratio (CNR of 26 landmarks were quantitatively measured and image quality qualitatively assessed using statistical analysis.As for the quantitative analysis, the difference of CNR between groups A and B was all significant except for the mesenteric vein. The SNR in group A was higher than B except the mesenteric artery and splenic artery. As for the qualitative analysis, all images had diagnostic quality and the agreement for image quality assessment between the reviewers was substantial (kappa = 0.684. CT dose index (CTDI values for non-enhanced, arterial phase and portal phase in group A were decreased by 49.04%, 40.51% and 40.54% compared with group B (P = 0.000, respectively. The total dose and the injection rate for the contrast material were reduced by 14.40% and 14.95% in A compared with B.The use of GSI and ASIR provides similar enhancement in vessels and image quality with reduced radiation dose and contrast dose, compared with the use of conventional scan protocol.

  20. Lethal, potentially lethal, and nonlethal damage induction by heavy ions in cultured human cells

    International Nuclear Information System (INIS)

    Todd, P.; Wood, J.C.; Walker, J.T.; Weiss, S.J.

    1985-01-01

    In the fields of high-LET radiotherapy and space radiation safety it is important to know the relative probabilities with which a cell whose nucleus is struck by a heavy ion will be damaged or killed. Experiments were performed in which synchronous cultured human T-1 cells (presumptive HeLa) were irradiated with natural alpha particles of energy approximately 3.5 MeV at various times after mitotic selection up to the middle of S phase. Nuclear-area histograms were determined as a function of time after mitosis under conditions identical to those used for irradiation. The efficiency with which one particle passing through the nucleus killed a cell was found to be 0.14-0.20. This value was extrapolated to experimental cell survival data obtained when asynchronous cultured human cells were irradiated with He, Li, B, C, N, O, Ne, Ar ions of energy 6.58 or 5.5 MeV/amu, and the cell killing efficiency was found to be in the broad range of 0.5-1.0 under single-hit conditions. Similarly irradiated cells were examined for colony-size distribution by an image analysis technique, and it was found that the loss of large colonies was dose and LET-dependent in a systematic way. Dose-response data suggest two predominant subpopulations, resistant and sensitive cells, and it appears that the sensitive population is affected by single-hit kinetics. The single-hit coefficient for the induction of inherited slow growth varied with LET in a similar way to that for survival. The action cross section for this form of heritable damage appears to be comparable to the geometric cross section of the cell nucleus

  1. Intensification of antitumor radiation effect by metronidazole and short-term hyperglycemia and dependence of therapeutic effect on schedules of fractionation and value of single dose

    International Nuclear Information System (INIS)

    Venkhvadze, N.G.

    1988-01-01

    Combined application of metronidazole and short-term hyperglycemia under fractionated irradiation of sarcoma-45, 340 in white rats-males is studied. Tumors were γ-irradiated with 60 Co threefold in 48 hours at 15 Gy single dose or irradiated threefold in a week at 20, 25 and 30 Gy doses. Efficiency of experimental therapy is cheked by dynamics of tumor regression, a number of animals with tumors reabsorbed temporarily, a number of animals recovered and time of tumor grouth up to the initial volume. It is established that combined application of metronidazole and short-term hyperglycemia under fractionated irradiation increases essentially the efficiency of radiotherapy carried out by large fractions with great time intervals. 7 refs.; 1 fig.; 2 tabs

  2. Radiation dose from solar flares at ground level

    International Nuclear Information System (INIS)

    O'Brien, K.

    1979-01-01

    Wdowczyk and Wolfendale (Nature, 268, 510, 1977) concluded that a very large solar flare producing exposure of 10 4 rad at ground level (lethal to almost any organism) has a possible frequency of once per 10 5 -10 8 yr. In the work reported similar results were obtained using a more elaborate model. Flares occuring from February 1956 to August 1972 were analyzed. The flare size distribution above the earth's atmosphere, and neutron flux, dose and dose equivalent at ground level at the latitude of Deep River, Canada, were calculated. The probable frequency of flares delivering various doses are given. Doses larger than 100 rad which have significant somatic effects on man and other animals may be delivered once in 10 6 years. The probability of 10 4 rad was found to be 10 -8 /yr. These calculations apply only to high geomagnetic latitudes. Field reversals during which the geomagnetic field is much weaker than current values total about 10% of the past 4 million years. This suggests that a very large flare delivering a large dose worldwide at ground level cannot be ruled out. (author)

  3. TECHNIQUE OF ESTIMATION OF ERROR IN THE REFERENCE VALUE OF THE DOSE DURING THE LINEAR ACCELERATOR RADIATION OUTPUT CALIBRATION PROCEDURE. Part 2. Dependence on the characteristics of collimator, optical sourse-distance indicator, treatment field, lasers and treatment couch

    Directory of Open Access Journals (Sweden)

    Y. V. Tsitovich

    2016-01-01

    Full Text Available To ensure the safety of radiation oncology patients needed to provide consistent functional characteristics of the medical linear accelerators, which affect the accuracy of dose delivery. To this end, their quality control procedures, which include the calibration of radiation output of the linac, the error in determining the dose reference value during which must not exceed 2 %, is provided. The aim is to develop a methodology for determining the error (difference between a measured value of quantity and its true value in determining this value, depending on the characteristics of the collimator, the source to surface distance pointer, lasers, radiation field and treatment table. To achieve the objectives have been carried out dosimetric measurements of Trilogy S/N 3567 linac dose distributions, on the basis of which dose errors depending on the accuracy setting the zero position of the collimator, the deviation of the collimator rotation isocenter, the sourcesurface distance pointer accuracy, field size accuracy, the accuracy of lasers and treatment table positioning were obtained. It was found that the greatest impact on the value of the error has the error in the optical SSD indication and the error in the lasers position in the plane perpendicular to the plane of incidence of the radiation beam (up to 3.64 % for the energy of 6 MV. Dose errors caused by error in the field size were different for two photon energies, and reached 2.54 % for 6 MeV and 1.33% for 18 MeV. Errors caused by the rest of the characteristic do not exceed 1 %. Thus, it is possible to express the results of periodic quality control of these devices integrated in linac in terms of dose and use them to conduct a comprehensive assessment of the possibility of clinical use of a linear accelerator for oncology patients irradiation on the basis of the calibration of radiation output in case of development of techniques that allow to analyze the influence dosimetric

  4. Differential replication of Foot-and-mouth disease viruses in mice determine lethality.

    Science.gov (United States)

    Cacciabue, Marco; García-Núñez, María Soledad; Delgado, Fernando; Currá, Anabella; Marrero, Rubén; Molinari, Paula; Rieder, Elizabeth; Carrillo, Elisa; Gismondi, María Inés

    2017-09-01

    Adult C57BL/6J mice have been used to study Foot-and-mouth disease virus (FMDV) biology. In this work, two variants of an FMDV A/Arg/01 strain exhibiting differential pathogenicity in adult mice were identified and characterized: a non-lethal virus (A01NL) caused mild signs of disease, whereas a lethal virus (A01L) caused death within 24-48h independently of the dose used. Both viruses caused a systemic infection with pathological changes in the exocrine pancreas. Virus A01L reached higher viral loads in plasma and organs of inoculated mice as well as increased replication in an ovine kidney cell line. Complete consensus sequences revealed 6 non-synonymous changes between A01L and A10NL genomes that might be linked to replication differences, as suggested by in silico prediction studies. Our results highlight the biological significance of discrete genomic variations and reinforce the usefulness of this animal model to study viral determinants of lethality. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. New observations on chronic intoxication by very small doses of sodium fluosilicate

    Energy Technology Data Exchange (ETDEWEB)

    Cristiani, H; Chausse, P

    1927-01-01

    It was determined that daily doses of approximately 0.1 of the lethal dose of sodium fluoride produced a fluoric cachexia in guinea pigs which caused the death of the animals in 2 or 3 months. Animals which were given 0.02 of the lethal dose of sodium fluoride were apparently in good health for a period of 10 months. However, after two or three years cachexia was likely to appear.

  6. Dose/dose-rate responses of shrimp larvae to UV-B radiation

    International Nuclear Information System (INIS)

    Damkaer, D.M.

    1981-01-01

    Previous work indicated dose-rate thresholds in the effects of UV-B on the near-surface larvae of three shrimp species. Additional observations suggest that the total dose response varies with dose-rate. Below 0.002 Wm -2 sub([DNA]) irradiance no significant effect is noted in activity, development, or survival. Beyond that dose-rate threshold, shrimp larvae are significantly affected if the total dose exceeds about 85 Jm -2 sub([DNA]). Predictions cannot be made without both the dose-rate and the dose. These dose/dose-rate thresholds are compared to four-year mean dose/dose-rate solar UV-B irradiances at the experimental site, measured at the surface and calculated for 1 m depth. The probability that the shrimp larvae would receive lethal irradiance is low for the first half of the season of surface occurrence, even with a 44% increase in damaging UV radiation. (orig.)

  7. A Recombinant Adenovirus Expressing Ovine Interferon Tau Prevents Influenza Virus-Induced Lethality in Mice.

    Science.gov (United States)

    Martín, V; Pascual, E; Avia, M; Rangel, G; de Molina, A; Alejo, A; Sevilla, N

    2016-01-06

    Ovine interferon tau (IFN-τ) is a unique type I interferon with low toxicity and a broad host range in vivo. We report the generation of a nonreplicative recombinant adenovirus expressing biologically active IFN-τ. Using the B6.A2G-Mx1 mouse model, we showed that single-dose intranasal administration of recombinant Ad5-IFN-τ can effectively prevent lethality and disease induced by highly virulent hv-PR8 influenza virus by activating the interferon response and preventing viral replication. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  8. Derivation of hazardous doses for amphibians acutely exposed to ionising radiation

    International Nuclear Information System (INIS)

    Fuma, Shoichi; Watanabe, Yoshito; Kawaguchi, Isao; Takata, Toshitaro; Kubota, Yoshihisa; Ban-nai, Tadaaki; Yoshida, Satoshi

    2012-01-01

    Derivation of effect benchmark values for each taxonomic group, which has been difficult due to lack of experimental effects data, is required for more adequate protection of the environment from ionising radiation. Estimation of effects doses from nuclear DNA mass and subsequent species sensitivity distribution (SSD) analysis were proposed as a method for such a derivation in acute irradiation situations for assumed nuclear accident scenarios. As a case study, 5% hazardous doses (HD 5 s), at which only 5% of species are acutely affected at 50% or higher lethality, were estimated on a global scale. After nuclear DNA mass data were obtained from a database, 50% lethal doses (LD 50 s) for 4.8 and 36% of the global Anura and Caudata species, respectively, were estimated by correlative equations between nuclear DNA mass and LD 50 s. Differences between estimated and experimental LD 50 s were within a factor of three. The HD 5 s obtained by the SSD analysis of these estimated LD 50 s data were 5.0 and 3.1 Gy for Anura and Caudata, respectively. This approach was also applied to the derivation of regional HD 5 s. The respective HD 5 s were 6.5 and 3.2 Gy for Anura and Caudata inhabiting Japan. This HD 5 value for the Japanese Anura was significantly higher than the global value, while Caudata had no significant difference in global and Japanese HD 5 s. These results suggest that this approach is also useful for derivation of regional benchmark values, some of which are likely different from the global values. - Highlights: ► A possible method was proposed for derivation of an effect benchmark value for each taxonomic group. ► 50% lethal doses were estimated from nuclear DNA mass in amphibian species. ► 5% hazardous doses (HD 5 s) were estimated by species sensitivity distribution. ► Respective HD 5 s were 5.0 and 3.1 Gy for Anura and Caudata globally. ► Respective HD 5 s were 6.5 and 3.2 Gy for Anura and Caudata inhabiting Japan.

  9. On dose distribution comparison

    International Nuclear Information System (INIS)

    Jiang, Steve B; Sharp, Greg C; Neicu, Toni; Berbeco, Ross I; Flampouri, Stella; Bortfeld, Thomas

    2006-01-01

    In radiotherapy practice, one often needs to compare two dose distributions. Especially with the wide clinical implementation of intensity-modulated radiation therapy, software tools for quantitative dose (or fluence) distribution comparison are required for patient-specific quality assurance. Dose distribution comparison is not a trivial task since it has to be performed in both dose and spatial domains in order to be clinically relevant. Each of the existing comparison methods has its own strengths and weaknesses and there is room for improvement. In this work, we developed a general framework for comparing dose distributions. Using a new concept called maximum allowed dose difference (MADD), the comparison in both dose and spatial domains can be performed entirely in the dose domain. Formulae for calculating MADD values for various comparison methods, such as composite analysis and gamma index, have been derived. For convenience in clinical practice, a new measure called normalized dose difference (NDD) has also been proposed, which is the dose difference at a point scaled by the ratio of MADD to the predetermined dose acceptance tolerance. Unlike the simple dose difference test, NDD works in both low and high dose gradient regions because it considers both dose and spatial acceptance tolerances through MADD. The new method has been applied to a test case and a clinical example. It was found that the new method combines the merits of the existing methods (accurate, simple, clinically intuitive and insensitive to dose grid size) and can easily be implemented into any dose/intensity comparison tool

  10. Deep inspiration breath-hold technique for lung tumors: the potential value of target immobilization and reduced lung density in dose escalation

    International Nuclear Information System (INIS)

    Hanley, J.; Debois, M.M.; Raben, A.; Mageras, G.S.; Lutz, W.R.; Mychalczak, B.; Schwartz, L.H.; Gloeggler, P.J.; Leibel, S.A.; Fuks, Z.; Kutcher, G.J.

    1996-01-01

    Purpose/Objective: Lung tumors are subject to movement due to respiratory motion. Conventionally, a margin is applied to the clinical target volume (CTV) to account for this and other treatment uncertainties. The purpose of this study is to evaluate the dosimetric benefits of a deep inspiration breath-hold (DIBH) technique which has two distinct features - deep inspiration which reduces lung density and breath-hold which immobilizes lung tumors. Both properties can potentially reduce the mass of normal lung tissue in the high dose region, thus improving the possibility of dose escalation. Methods and Materials: To study the efficacy of the DIBH technique, CT scans are acquired for each patient under 4 respiration conditions: free-breathing; DIBH; shallow inspiration breath-hold; shallow expiration breath-hold. The free-breathing and DIBH scans are used to generate treatment plans for comparison of standard and DIBH techniques, while the shallow inspiration and expiration scans provide information on the maximum extent of tumor motion under free-breathing conditions. To acquire the breath-hold scans, the patients are brought to reproducible respiration levels using spirometry and slow vital capacity maneuvers. For the treatment plan comparison free-breathing and DIBH planning target volumes (PTVs) are constructed consisting of the CTV plus a margin for setup error and lung tumor motion. For both plans the margin for setup error is the same while the margin for lung tumor motion differs. The margin for organ motion in free-breathing is determined by the maximum tumor excursions in the shallow inspiration and expiration CT scans. For the DIBH, tumor motion is reduced to the extent to which DIBH can be maintained and the margin for any residual tumor motion is determined from repeat fluoroscopic movies, acquired with the patient monitored using spirometry. Three-dimensional treatment plans, generated using apertures based on the free-breathing and DIBH PTVs, are

  11. Influence Of Quinolone Lethality on Irradiated Anaerobic Growth of Escherichia Coli

    International Nuclear Information System (INIS)

    Ibrahim, I.M.; El-Kabbany, H.M.; El-Esseily, E.SH.

    2012-01-01

    Bacteriostatic and bactericidal activities were measured with wild type cells and isomerase mutants of Escherichia coli for ciprofloxacin, formation of quinolone-gyrase-DNA complexes, observed as a sodium dodecyl sulfate (SDS) dependent drop in cell lysate viscosity, occurred during aerobic and anaerobic growth and in the presence and in the absence of chloramphenicol. Quinolone activity against Escherichia coli was examined during aerobic growth, aerobic treatment with chloramphenicol, and anaerobic growth. Nalidixic acid, norfloxacin and ciprofloxacin were lethal for cultures growing aerobically, and the bacteriostatic activity of each quinolone was unaffected by anaerobic growth. However, lethal activity was distinct for each quinolone with cells treated aerobically with chloramphenicol or grown anaerobically. Nalidixic acid failed to kill cells under both conditions, norfloxacin killed cells when they were grown anaerobically but not when they were treated with chloramphenicol, ciprofloxacin killed cells under both conditions but required higher concentrations than those required with cells grown aerobically, C-methoxy fluoro quinolone was equally lethal under all conditions. However, lethal chromosome fragmentation, detected as a drop in viscosity in the absence of SDS, was occurred with nalidixic acid treatment only under aerobic conditions in the absence of chloramphenicol, thus, all quinolones tested appeared to form reversible bacteriostatic complexes containing broken DNA during aerobic growth, during anaerobic growth, and when protein synthesis is blocked. The ability to fragment chromosomes rapidly kill cells under these conditions depends on quinolone structure. The radiation of sublethal dose was 3 Gy at rate of 0.6 Gy/min was shown as non-significant result

  12. Changes in rat liver and adipose tissue lipogenesis after single lethal X-irradiation: modification by the restricted food intake

    International Nuclear Information System (INIS)

    Sedlakova, A.; Ahlers, I.; Praslicka, M.

    1981-01-01

    Male rats of Wistar strain were adapted during a 4-week period to the nutritional regimes of meal feeding (MF) and ad libitum (AL) and were irradiated with the single whole-body lethal X-ray dose 14.35 Gy after 22 h of fasting. Within the intervals 1, 24, 48 and 72 h after irradiation lipogenesis changes in the liver were studied by measuring 1- 14 C-acetate incorporation (74 KBq) in the total lipids, fatty acids and cholesterol, and in the white adipose tissue pieces by measuring U- 14 C-glucose incorporation (74 KBq) in the total lipids, fatty acids and glyceride glycerol. Lipogenesis increased in the liver of the irradiated rats as compared with sham irradiated rats and reached the maximal values at 72 h after irradiation in AL animals and at 48 h after irradiation in MF animals. Lipogenesis in the adipose tissue decreased in the irradiated rats as compared with the sham irradiated ones and continued to decrease with the post-irradiation period. The adaptation to the nutritional regime of meal feeding markedly modified lipogenesis in the liver and the adipose tissue of the irradiated rats. Long-term fasting (before and after irradiation) was supposed to be another modifying factor in the lipogenesis changes. Lipogenesis changes in the liver depended on the MF nutritional regime. (author)

  13. Changes in rat liver and adipose tissue lipogenesis after single lethal X-irradiation: modification by the restricted food intake

    Energy Technology Data Exchange (ETDEWEB)

    Sedlakova, A; Ahlers, I; Praslicka, M [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

    1981-01-01

    Male rats of Wistar strain were adapted during a 4-week period to the nutritional regimes of meal feeding (MF) and ad libitum (AL) and were irradiated with the single whole-body lethal X-ray dose 14.35 Gy after 22 h of fasting. Within the intervals 1, 24, 48 and 72 h after irradiation lipogenesis changes in the liver were studied by measuring 1-/sup 14/C-acetate incorporation (74 KBq) in the total lipids, fatty acids and cholesterol, and in the white adipose tissue pieces by measuring U-/sup 14/C-glucose incorporation (74 KBq) in the total lipids, fatty acids and glyceride glycerol. Lipogenesis increased in the liver of the irradiated rats as compared with sham irradiated rats and reached the maximal values at 72 h after irradiation in AL animals and at 48 h after irradiation in MF animals. Lipogenesis in the adipose tissue decreased in the irradiated rats as compared with the sham irradiated ones and continued to decrease with the post-irradiation period. The adaptation to the nutritional regime of meal feeding markedly modified lipogenesis in the liver and the adipose tissue of the irradiated rats. Long-term fasting (before and after irradiation) was supposed to be another modifying factor in the lipogenesis changes. Lipogenesis changes in the liver depended on the MF nutritional regime.

  14. The Clinical Value of Non-Coplanar Photon Beams in Biologically Optimized Intensity Modulated Dose Delivery on Deep-Seated Tumours

    International Nuclear Information System (INIS)

    Ferreira, Brigida C.; Svensson, Roger; Loef, Johan; Brahme, Anders

    2003-01-01

    The aim of the present study is to compare the merits of different radiobiologically optimized treatment techniques using few-field planar and non-coplanar dose delivery on an advanced cancer of the cervix, with rectum and bladder as principal organs at risk. Classically, the rational for using non-coplanar beams is to minimize the overlap of beam entrance and exit regions and to find new beam directions avoiding organs at risk, in order to reduce damage to sensitive normal tissues. Two four-beam configurations have been extensively studied. The first consists of three evenly spaced coplanar beams and a fourth non-coplanar beam. A second tetrahedral-like configuration, with two symmetric non-coplanar beams at the same gantry angle and two coplanar beams, with optimized beam directions, was also tested. The present study shows that when radiobiologically optimized intensity modulated beams are applied to such a geometry, only a marginal increase in the treatment outcome can be achieved by non-coplanar beams compared to the optimal coplanar treatment. The main reason for this result is that the high dose in the beam-overlap regions is already optimally reduced by biologically optimized intensity modulation in the plane. The large number of degrees of freedom already incorporated in the treatment by the use of intensity modulation and radiobiological optimization, leads to the saturation of the benefit acquired by a further increase in the degrees of freedom with non-coplanar beams. In conclusion, the use coplanar of radiobiologically optimized intensity modulation simplifies the dose delivery, reducing the need for non-coplanar beam portals

  15. The value of regional nodal radiotherapy (dose/volume) in the treatment of unresectable non-small cell lung cancer: an RTOG analysis

    International Nuclear Information System (INIS)

    Emami, Bahman; Scott, Charles; Byhardt, Roger; Graham, Mary V.; Andras, E. James; John, Madhu; Herskovic, Arnold; Urtasun, Raul C.; Asbell, Sucha O.; Perez, Carlos A.; Cox, James

    1996-01-01

    PURPOSE/OBJECTIVE: To evaluate whether or not the traditional practice of including all thoracic regional nodal areas in the radiotherapy volume in the treatment of unresectable lung cancer is of any therapeutic benefit. MATERIALS AND METHODS: A total of 1,705 patients from four large RTOG trials (78-11, 79-17, 83-11, 84-07) were analyzed for this purpose. Each of these trials had data on dose delivered to the nodal regions and assessment of nodal borders. The nodes were separated into mediastinal, contralateral hilar, ipsilateral hilar, and supraclavicular. Each node site was assessed for progression, defined as in-field or out-of-field, at the node site. In patients with adequate nodal field borders, the results were also analyzed according to the dose delivered. RESULTS: The majority (74%) of patients were between the age of 55 to 75. Forty-six percent of patients had KPS of 60 to 80 and 52% KPS of 90 to 100. Sixty percent of patients had a weight loss of less than 5%, and 40% had a weight loss of over 5% six months prior to diagnosis. Major variations from protocol in defining field borders (unacceptable field borders) were lowest for ipsilateral hilum ((42(727))) and the highest for mediastinal borders ((158(743))). Three groups had statistically significant differences in outcome (progression) between the per protocol and the unacceptable per protocol: ipsilateral hilar nodes (field borders), 14% versus 26% (p = 0.03); dose to mediastinal nodes in CALGB eligible patients, 9% versus 19% (p = 0.02); and ipsilateral hilar nodes (field borders) for high-dose patients assigned to greater than or equal to 69.6 Gy, 14% versus 31% (p = 0.007). CONCLUSION: These data suggest that inclusion of the ipsilateral hilar and mediastinal nodes affect outcome in unresectable non-small cell lung cancer. Exclusion of the other thoracic lymph node regions did not affect outcome in this study. These findings have important implications for combined modality therapy and three

  16. Effect of different radiation doses on pupae of cabbage butterfly, (pieris brassicae)

    International Nuclear Information System (INIS)

    Sattar, A.; Khattak, S.U.

    1989-01-01

    The lots of 12 pupae, 3-2 days old, were irradiated at different radiation doses for each treatment. There was no emergence at 40 Krad showing that this dose was the lethal dose for the pupae of this insects. There was a significant reduction in adult emergence below this dose. (A.B.)

  17. Induction of dominant lethal mutations by gamma irradiation of Gallus domesticus spermatozoa

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, J; Grom, A; Csuka, J; Kindlova, L [Poultry Research Institute, Ivanka pri Dunaji (Czechoslovakia)

    1977-01-01

    Mixed semen of Gallus domesticus cocks was gamma irradiated in vitro with exposures of 500, 1000, 2000, and 3000 R at the exposure rate of 5.86 Rs/sup -1/. After the irradiation the semen was applied to experimental and control layer hens, the embryonic mortality in F/sub 1/ was observed, the total number of incubated eggs was 3344. Irradiation with 500 R had a favourable influence on embryonic vitality, the exposures 1000, 2000, and 3000 R resulted in increased embryonic mortality, for 2100 R a 50% mortality of offspring was found. Induced dominant lethality was manifest during embryonic and oviduct development. The frequency of induced dominant lethality for exposures used was 19.2, 9.9, 48.3, and 69.1%, the values of mutation rate were 0.087, 0.104, 0.659, and 1.174. The mutation rate had a linear course, the value of the lethal hit per gamete for 1 R was 1.04x10/sup -4/.

  18. PENGARUH PENGGUNAAN LETHAL OVITRAP TERHADAP POPULASI NYAMUK AEDES SP SEBAGAI VEKTOR DEMAM BERDARAH DENGUE

    Directory of Open Access Journals (Sweden)

    Tri Ramadhani

    2013-09-01

    Full Text Available ABSTRACT. Field evaluation against lethal ovitrap (LO to control dengue vector Aedes mosquitoes carried intwo endemic areas (Bojongsari and Ledug in Banyumas. Lethal ovitrap made ?with the intent to kill mosquito,because mosquitoes will lay eggs containing ovistrip contact with the insecticide and the relatively short time todie.The aim of research to assess the effect of LO applications with the Aedes of mosquito populations sp. Thisstudy includes a quasi experimental design with pretest-posttest control group without randomization. Researchsites in dengue endemic areas with a total sample of 100 houses in each treatment and control areas. Populationsof Aedes sp measured every week for three weeks prior to the intervention and twelve weeks during theintervention. The mean density of Aedes sp compared before and after intervention and between the treatment andcontrol. Results showed mean mosquito density before and after the intervention in the treatment group of 0.07(p-value 0.044, whereas in the control group by 0037 ( p-value 0341. Use LO made ?with the addition ofinsecticide active cypermetrin on ovistrip impact on the density of Aedes sp in the residential neighborhood.Keywords: lethal ovitrap, DHF, Aedes sp

  19. Induction of dominant lethal mutations by gamma irradiation of Gallus domesticus spermatozoa

    International Nuclear Information System (INIS)

    Baumgartner, J.; Grom, A.; Csuka, J.; Kindlova, L.

    1977-01-01

    Mixed semen of Gallus domesticus cocks was gamma irradiated in vitro with exposures of 500, 1000, 2000 and 3000 R at the exposure rate of 5.86 Rs -1 . After the irradiation the semen was applied to experimental and control layer hens, the embryonic mortality in F 1 was observed, the total number of incubated eggs was 3344. Irradiation with 500 R had a favourable influence on embryonic vitality, the exposures 1000, 2000 and 3000 R resulted in increased embryonic mortality, for 2100 R a 50% mortality of offspring was found. Induced dominant lethality was manifest during embryonic and oviduct development. The frequency of induced dominant lethality for exposures used was 19.2, 9.9, 48.3, and 69.1%, the values of mutation rate were 0.087, 0.104, 0.659, and 1.174. The mutation rate had linear course, the value of the lethal hit per gamete for 1 R was 1.04x10 -4 . (author)

  20. Effects of β-arabinofuranosyladenine on the growth and repair of potentially lethal damage in Ehrlich ascites tumor cells

    International Nuclear Information System (INIS)

    Iliakis, G.

    1980-01-01

    β-D-Arabinofuranosyladenine (β-araA) inhibit the growth of Ehrlich ascites tumor cells by selective inhibition of DNA polymerases. RNA and protein synthesis are not significantly affected. Addition of β-araA to the cells after irradiation resulted in a concentration-dependent decrease in survival, presumably due to the inhibition of the repair of potentially lethal damage. Since β-araA selectively inhibits DNA polymerases it is suggested that repair of potentially lethal damage involves steps at the DNA level which require some polymerization. These repair steps take place in the DNA with a velocity comparable to that of the repair of potentially lethal damage. The inhibition of the repair of potentially lethal damage by β-araA was modified by the addition of deoxyadenosine; this supports the finding that β-araA acts competitively against dATP at the molecular level. The inhibition of the repair of potentially lethal damage by β-araA, which is partly reversible, resulted in a concentration-dependent modification of the survival curve. At low concentrations of β-araA a dose-modifying decrease in survival was observed. At higher concentrations (more than 12 μM) the decrease in survival resulted in a decrease of the shoulder width of the survival curve. Eventually an exponential curve was obtained. We suggest therefore that the shoulder of the survival curve results from some repair or potentially lethal damage. Preliminary information has been obtained on the time course of this repair

  1. A new type of lethal short-limbed dwarfism

    International Nuclear Information System (INIS)

    Nairn, E.R.; Chapman, S.

    1989-01-01

    Details are presented of a most unusual osteo-chondrodysplasia which presents with lethal neonatal short-limbed dwarfism, defective ossification and nodular calcification with cartilage. The features resemble one case previously described in the literature. (orig.)

  2. Back to the future: revisiting HIV-1 lethal mutagenesis

    Science.gov (United States)

    Dapp, Michael J.; Patterson, Steven E.; Mansky, Louis M.

    2012-01-01

    The concept of eliminating HIV-1 infectivity by elevating the viral mutation rate was first proposed over a decade ago, even though the general concept had been conceived earlier for RNA viruses. Lethal mutagenesis was originally viewed as a novel chemotherapeutic approach for treating HIV-1 infection in which use of a viral mutagen would over multiple rounds of replication lead to the lethal accumulation of mutations, rendering the virus population non infectious – known as the slow mutation accumulation model. There have been limitations in obtaining good efficacy data with drug leads, leaving some doubt into clinical translation. More recent studies of the APOBEC3 proteins as well as new progress in the use of nucleoside analogs for inducing lethal mutagenesis have helped to refocus attention on rapid induction of HIV-1 lethal mutagenesis in a single or limited number of replication cycles leading to a rapid mutation accumulation model. PMID:23195922

  3. New type of lethal short-limbed dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Nairn, E.R.; Chapman, S.

    1989-05-01

    Details are presented of a most unusual osteo-chondrodysplasia which presents with lethal neonatal short-limbed dwarfism, defective ossification and nodular calcification with cartilage. The features resemble one case previously described in the literature.

  4. Values of (99m)Tc-methoxyisobutylisonitrile imaging after first-time large-dose (131)I therapy in treating differentiated thyroid cancer.

    Science.gov (United States)

    Pan, Xiaomei; Duan, Dong; Zhu, Yuquan; Pang, Hua; Guan, Lili; Lv, Zhixiang

    2016-01-01

    The aim of this study is to investigate the use of (99m)Tc-methoxyisobutylisonitrile (MIBI) imaging for evaluating the treatment response of differentiated thyroid cancer (DTC) after the first administration of a high dose of (131)I. Patients with DTC who received (131)I therapy underwent (99m)Tc-MIBI imaging after successive increases in the therapeutic dose of (131)I, and the serum levels of thyroglobulin (Tg) were measured. A total of 191 patients were enrolled in the final analysis, including 65 metastases and/or thyroid remnant-positive patients (22 patients with metastases and 43 patients with thyroid remnants). The sensitivity of (99m)Tc-MIBI imaging for detecting positive cases and thyroid remnants was 56.9% and 39.5%, respectively, which was significantly lower than that of (131)I imaging (92.3% and 100%, respectively, PTc-MIBI imaging for detecting metastases was 90.9%, which was slightly higher than that of (131)I imaging (77.3%, P>0.05). The Tg levels in the positive group were significantly higher than that in the negative group (PTc-MIBI(+)/(131)I(-) group were significantly higher than that in the (131)I(+)/(99m)Tc-MIBI group (PTc-MIBI imaging was able to detect the existence of metastatic lesions in patients with DTC better, its assessment for the removal efficiency of thyroid remnants was unsatisfactory. The results of (99m)Tc-MIBI imaging showed good correlations with the Tg level.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-03-15

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

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

    International Nuclear Information System (INIS)

    Zhou, Dunhua; Deoliveira, Divino; Kang, Yubin; Choi, Seung S.; Li, Zhiguo; Chao, Nelson J.; Chen, Benny J.

    2013-01-01

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

  7. Perinatal-lethal Gaucher disease presenting as hydrops fetalis.

    Science.gov (United States)

    BenHamida, Emira; Ayadi, Imene; Ouertani, Ines; Chammem, Maroua; Bezzine, Ahlem; BenTmime, Riadh; Attia, Leila; Mrad, Ridha; Marrakchi, Zahra

    2015-01-01

    Perinatal-lethal Gaucher disease is very rare and is considered a variant of type 2 Gaucher disease that occurs in the neonatal period. The most distinct features of perinatal-lethal Gaucher disease are non-immune hydrops fetalis. Less common signs of the disease are hepatosplenomegaly, ichthyosis and arthrogryposis. We report a case of Gaucher's disease (type 2) diagnosed in a newborn who presented with Hydrops Fetalis.

  8. Conflict Without Casualties: Non-Lethal Weapons in Irregular Warfare

    Science.gov (United States)

    2007-09-01

    the body,” and the Geneva Protocol of 1925, bans the use of chemical and biological weapons .11 On 8 April 1975, President Ford issued Executive...E Funding – PE 63851M) (accessed 15 December 2006). The American Journal of Bioethics . “Medical Ethics and Non-Lethal Weapons .” Bioethics.net...CASUALTIES: NON-LETHAL WEAPONS IN IRREGULAR WARFARE by Richard L. Scott September 2007 Thesis Advisor: Robert McNab Second Reader

  9. Non-Lethal Weapons: Opportunities for R&D

    Science.gov (United States)

    2004-12-01

    during the Vietnam War. US; emulsifying agents are used in food processing, drilling fluids, cosmetics , pharmaceuticals, heavy- duty cleaners, textile...conducted in a professional manner, with no threat to public safety or the environment. 11 References [1] Fenton , G., (2001). NLW Technology Taxonomy...W.A., Mason, R.L., Collins, K.R., (2000). Non-Lethal Applicants of Slippery Substances. NDIA Non-Lethal Defense IV. [24] Fenton , G., (2000). Overview

  10. Lethal synergy involving bicyclomycin: an approach for reviving old antibiotics.

    Science.gov (United States)

    Malik, Muhammad; Li, Liping; Zhao, Xilin; Kerns, Robert J; Berger, James M; Drlica, Karl

    2014-12-01

    One way to address the growing problem of antimicrobial resistance is to revive old compounds that may have intrinsic lethal activity that is obscured by protective factors. Bicyclomycin is an old inhibitor of the Rho transcription terminator that by itself shows little rapid lethal activity. However, bicyclomycin participates in bacteriostatic synergy, which raises the possibility that conditions for lethal synergy may exist, perhaps through a suppression of protective factors. Bicyclomycin was combined with bacteriostatic inhibitors of gene expression, and bactericidal activity was measured with several cultured Gram-negative pathogens. When used alone, bicyclomycin failed to rapidly kill growing cultures of Escherichia coli; however, the additional presence of bacteriostatic concentrations of tetracycline, chloramphenicol or rifampicin led to rapid killing. Four other pathogen species, Acinetobacter baumannii, Klebsiella pneumoniae, Salmonella enterica serotype Typhimurium and Shigella dysenteriae, also exhibited enhanced killing when bicyclomycin was combined with tetracycline or rifampicin. This lethal synergy was achieved at low concentrations (slightly above the MIC) for all agents tested in combinations. Follow-up work with E. coli indicated that lethal synergy arose from a blockage of transcription elongation. Moreover, lethal synergy was reduced when bicyclomycin was added 60 min before tetracycline, suggesting that bicyclomycin induces a protective factor. The action of bicyclomycin illustrates the potential present in a largely abandoned antibacterial agent; it exhibits lethal synergy when coadministered with known, bacteriostatic inhibitors of gene expression. The identification of protective factors, which are currently uncharacterized, may reveal new ways to promote the lethal action of some old antibiotics. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved

  11. Sonographic features of lethal multiple pterygium syndrome at 14 weeks.

    Science.gov (United States)

    Chen, Min; Chan, Gavin Shueng Wai; Lee, Chin Peng; Tang, Mary Hoi Yin

    2005-06-01

    Lethal multiple pterygium syndrome is a rare inherited disorder. Previous reports suggest that the diagnosis may be based on prenatal sonographic demonstration of severe limb flexion, absence of fetal motion, and a large cystic hygroma in the second and third trimesters. We present the sonographic features and postmortem features of a fetus with lethal multiple pterygium syndrome at 13 weeks of gestation, which shows that the condition can possibly be diagnosed in the first trimester of pregnancy.

  12. Determination of body diameters of babies, children and adolescents to list exposure values in X-ray diagnostics and estimation of organ dose values for typical X-ray examinations

    International Nuclear Information System (INIS)

    Bohmann, I.

    1990-04-01

    Measurements of body diameters of children did not exist as yet. Therefore the body diameters of 270 children, male and female, were measured, together with weight and height. The children were healthy and chosen at random. Six groups regarding age were considered: Newborn, one, five, seven, ten, fifteen years old. From the measurements mean values and standard deviations were calculated. In addition the correlations of the body diameters with age, weight, and height were investigated. The mean values of weight and height were compared to literature data. Exposure tables for children now, for the first time, can be established on the basis of empirical results. (orig.) [de

  13. Cancer radiotherapy based on femtosecond IR laser-beam filamentation yielding ultra-high dose rates and zero entrance dose.

    Science.gov (United States)

    Meesat, Ridthee; Belmouaddine, Hakim; Allard, Jean-François; Tanguay-Renaud, Catherine; Lemay, Rosalie; Brastaviceanu, Tiberius; Tremblay, Luc; Paquette, Benoit; Wagner, J Richard; Jay-Gerin, Jean-Paul; Lepage, Martin; Huels, Michael A; Houde, Daniel

    2012-09-18

    Since the invention of cancer radiotherapy, its primary goal has been to maximize lethal radiation doses to the tumor volume while keeping the dose to surrounding healthy tissues at zero. Sadly, conventional radiation sources (γ or X rays, electrons) used for decades, including multiple or modulated beams, inevitably deposit the majority of their dose in front or behind the tumor, thus damaging healthy tissue and causing secondary cancers years after treatment. Even the most recent pioneering advances in costly proton or carbon ion therapies can not completely avoid dose buildup in front of the tumor volume. Here we show that this ultimate goal of radiotherapy is yet within our reach: Using intense ultra-short infrared laser pulses we can now deposit a very large energy dose at unprecedented microscopic dose rates (up to 10(11) Gy/s) deep inside an adjustable, well-controlled macroscopic volume, without any dose deposit in front or behind the target volume. Our infrared laser pulses produce high density avalanches of low energy electrons via laser filamentation, a phenomenon that results in a spatial energy density and temporal dose rate that both exceed by orders of magnitude any values previously reported even for the most intense clinical radiotherapy systems. Moreover, we show that (i) the type of final damage and its mechanisms in aqueous media, at the molecular and biomolecular level, is comparable to that of conventional ionizing radiation, and (ii) at the tumor tissue level in an animal cancer model, the laser irradiation method shows clear therapeutic benefits.

  14. An orally available, small-molecule polymerase inhibitor shows efficacy against a lethal morbillivirus infection in a large animal model.

    Science.gov (United States)

    Krumm, Stefanie A; Yan, Dan; Hovingh, Elise S; Evers, Taylor J; Enkirch, Theresa; Reddy, G Prabhakar; Sun, Aiming; Saindane, Manohar T; Arrendale, Richard F; Painter, George; Liotta, Dennis C; Natchus, Michael G; von Messling, Veronika; Plemper, Richard K

    2014-04-16

    Measles virus is a highly infectious morbillivirus responsible for major morbidity and mortality in unvaccinated humans. The related, zoonotic canine distemper virus (CDV) induces morbillivirus disease in ferrets with 100% lethality. We report an orally available, shelf-stable pan-morbillivirus inhibitor that targets the viral RNA polymerase. Prophylactic oral treatment of ferrets infected intranasally with a lethal CDV dose reduced viremia and prolonged survival. Ferrets infected with the same dose of virus that received post-infection treatment at the onset of viremia showed low-grade viral loads, remained asymptomatic, and recovered from infection, whereas control animals succumbed to the disease. Animals that recovered also mounted a robust immune response and were protected against rechallenge with a lethal CDV dose. Drug-resistant viral recombinants were generated and found to be attenuated and transmission-impaired compared to the genetic parent virus. These findings may pioneer a path toward an effective morbillivirus therapy that could aid measles eradication by synergizing with vaccination to close gaps in herd immunity due to vaccine refusal.

  15. Effect of duration of contrast material injection on peak enhancement times and values of the aorta, main portal vein, and liver at dynamic MDCT with the dose of contrast medium tailored to patient weight

    International Nuclear Information System (INIS)

    Erturk, S.M.; Ichikawa, T.; Sou, H.; Tsukamoto, T.; Motosugi, U.; Araki, T.

    2008-01-01

    Aim: To investigate the effects of contrast material injection duration on peak enhancement times and attenuation values of the aorta, main portal vein, and liver at MDCT when the dose of contrast material is adjusted to patient weight. Material and methods: Seventy-five patients were randomly assigned to one of five groups, with durations of injection of 25, 30, 35, 40, or 45 s. All patients were injected with 2 ml/kg iodine (300 mg/ml). Attenuation values and peak enhancement times for the aorta, main portal vein, and liver were determined. The relationship between patient weight and enhancement times and values, the differences regarding peak enhancement times, and the relationship between injection duration and enhancement values were investigated using Pearson correlation, analysis of variance (ANOVA), and Spearman rank correlation, respectively. Results: No significant correlations were seen between patient weight and peak enhancement times or values. Mean peak enhancement times for the aorta, main portal vein, and liver were 9-11 s, 18-22 s, and 30-34 s, respectively (p > 0.05). The correlations between injection duration and peak enhancement values were significant and negative. Conclusions: Regardless of patient weight and injection duration, peak enhancement times of aorta, main portal vein and liver were approximately 10, 20, and 30 s, respectively. The enhancement values tended to be higher for shorter injection durations

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  17. Diagnostic value of whole-body low-dose computed tomography (WBLDCT) in bone lesions detection in patients with multiple myeloma (MM)

    Energy Technology Data Exchange (ETDEWEB)

    Ippolito, Davide, E-mail: davide.atena@tiscalinet.it [School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza (MB) (Italy); Department of Diagnostic Radiology, H. San Gerardo, Via Pergolesi 33, 20900 Monza (MB) (Italy); Besostri, Valeria, E-mail: valeriabesostri@gmail.com [School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza (MB) (Italy); Department of Diagnostic Radiology, H. San Gerardo, Via Pergolesi 33, 20900 Monza (MB) (Italy); Bonaffini, Pietro Andrea, E-mail: pa.bonaffini@gmail.com [School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza (MB) (Italy); Department of Diagnostic Radiology, H. San Gerardo, Via Pergolesi 33, 20900 Monza (MB) (Italy); Rossini, Fausto, E-mail: valeriabesostri@hotmail.it [Department of Hematology, H. San Gerardo, Via Pergolesi 33, 20900 Monza (MB) (Italy); Di Lelio, Alessandro, E-mail: valebeso@libero.it [Department of Diagnostic Radiology, H. San Gerardo, Via Pergolesi 33, 20900 Monza (MB) (Italy); Sironi, Sandro, E-mail: sandrosironi@libero.it [School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza (MB) (Italy); Department of Diagnostic Radiology, H. San Gerardo, Via Pergolesi 33, 20900 Monza (MB) (Italy)

    2013-12-01

    Purpose: To assess the role of whole-body low-dose computed tomography (WBLDCT) in the diagnosis and staging of patients with suspicion of multiple myeloma (MM). Materials and methods: A total of 138 patients (76 male and 62 female; mean age 63.5 years, range 50–81 years), with early MM, underwent WBLDCT protocol study, performed on 16-slice scanner (Brilliance, Philips Medical System, Eindhoven, The Netherlands): tube voltage 120 kV; tube current time product 40 mAs. Diagnosis of osteolytic lesions was performed on the basis of axial and multiplanar reformatted images, whereas the assessment of spinal misalignment and fracture was done by using multiplanar reformatted images. The overall dose delivered to each patient was 4.2 mSv. Every patient gave personal informed consent, as required by our institution guidelines. Results: The diagnosis was established either by histopathology or imaging follow-up (size increase of over a period time). In all 138 patients, image resolution was diagnostic, enabling correct classification of multiple myeloma patients. WBLDCT showed a total of 328 pathologic bone findings in 81/138 patients. CT scanning resulted in complete evaluation of the bone lesions in these areas of the skeleton: skull (42), humerus (15), femur (20), ribs (7), scapulae (13), pelvis (35), clavicle (13), sternum (10), cervical (39), dorsal (65), lombar (48) and sacral rachis (21). In 40/81 bone involvement detected by CT was the only CRAB criterion present. Furthermore, WBLDCT demonstrated pleuro-pulmonary lesions in 20 patients (11 infective, 9 as MM localizations) and 1 renal neoplasia. Conclusion: WBLDCT, detecting bone marrow localizations and demonstrating extra-osseous findings, with a fast scanning time and high resolution images, is a reliable imaging-based tool for a proper management of MM patients.

  18. Relative biological effectiveness measurements using murine lethality and survival of intestinal and hematopoietic stem cells after Fermilab neutrons compared to JANUS reactor neutrons and 60Co gamma rays

    International Nuclear Information System (INIS)

    Hanson, W.R.; Crouse, D.A.; Fry, R.J.M.; Ainsworth, E.J.

    1984-01-01

    The relative biological effectiveness (RBE) of the 25-MeV (average energy) neutron beam at the Fermi National Accelerator Laboratory was measured using murine bone marrow (LD/sub 50/30/) and gut (LD/sub 50/6/) lethality and killing of hematopoietic colony forming units (CFU-S) or intestinal clonogenic cells (ICC). The LD/sub 50/30/ and LD/sub 50/6/ for mice exposed to the Fermilab neutron beam were 6.6 and 8.7 Gy, respectively, intermediate between those of JANUS neutrons and 60 Co γ rays. The D 0 values for CFU-S and ICC were 47 cGy and 1.05 Gy, respectively, also intermediate between the lowest values found for JANUS neutrons and the highest values found after 60 Co γ rays. The split-dose survival ratios for CFU-S at intervals of 1-6 hr between doses were essentially 1.0 for both neutron sources. The 3-hr split-dose survival ratios for ICC were 1.0 for JANUS neutrons, 1.85 for Fermilab neutrons, and 6.5 for 60 Co γ rays. The RBE estimates for LD/sub 50/30/ were 1.5 and 2.3 for Fermilab and JANUS neutrons, respectively. Based on LD/sub 50/6/, the RBEs were 1.9 (Fermilab) and 3.0 (JANUS). The RBEs for CFU-S D 0 were 1.4 (Fermilab) and 1.9 (JANUS) and for jejunal microcolony D 0 1.4 (Fermilab) and 2.8 (JANUS)

  19. Using Microsoft Excel to compute the 5% overall site X/Q value and the 95th percentile of the distribution of doses to the nearest maximally exposed offsite individual (MEOI).

    Science.gov (United States)

    Vickers, Linda D

    2010-05-01

    This paper describes the method using Microsoft Excel (Microsoft Corporation One Microsoft Way Redmond, WA 98052-6399) to compute the 5% overall site X/Q value and the 95th percentile of the distribution of doses to the nearest maximally exposed offsite individual (MEOI) in accordance with guidance from DOE-STD-3009-1994 and U.S. NRC Regulatory Guide 1.145-1982. The accurate determination of the 5% overall site X/Q value is the most important factor in the computation of the 95th percentile of the distribution of doses to the nearest MEOI. This method should be used to validate software codes that compute the X/Q. The 95th percentile of the distribution of doses to the nearest MEOI must be compared to the U.S. DOE Evaluation Guide of 25 rem to determine the relative severity of hazard to the public from a postulated, unmitigated design basis accident that involves an offsite release of radioactive material.

  20. Lethal and sublethal effects of imidacloprid on Osmia lignaria and clothianidin on Megachile rotundata (Hymenoptera: Megachilidae).

    Science.gov (United States)

    Abbott, V A; Nadeau, J L; Higo, H A; Winston, M L

    2008-06-01

    We examined lethal and sublethal effects of imidacloprid on Osmia lignaria (Cresson) and clothianidin on Megachile rotundata (F.) (Hymenoptera: Megachilidae). We also made progress toward developing reliable methodology for testing pesticides on wild bees for use in pesticide registration by using field and laboratory experiments. Bee larvae were exposed to control, low (3 or 6 ppb), intermediate (30 ppb), or high (300 ppb) doses of either imidacloprid or clothianidin in pollen. Field experiments on both bee species involved injecting the pollen provisions with the corresponding pesticide. Only O. lignaria was used for the laboratory experiments, which entailed both injecting the bee's own pollen provisions and replacing the pollen provision with a preblended pollen mixture containing imidacloprid. Larval development, emergence, weight, and mortality were monitored and analyzed. There were no lethal effects found for either imidacloprid or clothianidin on O. lignaria and M. rotundata. Minor sublethal effects were detected on larval development for O. lignaria, with greater developmental time at the intermediate (30 ppb) and high doses (300 ppb) of imidacloprid. No similar sublethal effects were found with clothianidin on M. rotundata. We were successful in creating methodology for pesticide testing on O. lignaria and M. rotundata; however, these methods can be improved upon to create a more robust test. We also identified several parameters and developmental stages for observing sublethal effects. The detection of sublethal effects demonstrates the importance of testing new pesticides on wild pollinators before registration.

  1. RBE-LET relationships for different types of lethal radiation damage in mammalian cells: comparison with DNA dsb and an interpretation of differences in radiosensitivity

    NARCIS (Netherlands)

    Barendsen, G. W.

    1994-01-01

    Relative biological effectiveness (RBE), as a function of linear energy transfer (LET), is evaluated for different types of damage contributing to mammalian cell reproductive death. Survival curves are analysed assuming a linear-quadratic dose dependence of lethal lesions. The linear term represents

  2. X-ray lethality in diabetic rats

    International Nuclear Information System (INIS)

    Cember, H.; Thorson, T.M. Jr.

    1978-01-01

    Rats were made diabetic with streptozotocin and were irradiated with X-rays at various exposure levels in order to determine the LD-50/30 day dose. Non-diabetic control rats were exposed in a similar manner. The LD-50 exposures for the diabetic rats and the control rats were 436 R, and 617 R respectively. In view of the high prevalence of diabetes among the adult population, this finding may have important implications for diabetic workers who may be exposed accidentally to high levels of ionizing radiation

  3. Toxicology Studies on Lewisite and Sulfur Mustard Agents: Modified Dominant Lethal Study of Sulfur Mustard in Rats Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sasser, L. B.; Cushing, J. A.; Kalkwarf, D. R.; Buschbom, R. L.

    1989-05-01

    Occupational health standards have not been established for sulfur mustard (HD) [bis{2-chloroethyl)-sulfide) ' a strong alkylating agent with known mutagenic properties. Little, however, is known about the mutagenic activity of HD in mammalian species and data regarding the dominant lethal effects of HD are ambiguous. The purpose of this study was to determine the dominant lethal effect in male and female rats orally exposed to HD. The study was conducted in two phases; a female dominant lethal phase and a male dominant lethal phase. Sprague-Dawley rats of each sex were administered 0.08, 0.20, or 0.50 mg/kg HD in sesame oil 5 days/week for 10 weeks. For the female phase, treated or untreated males were mated with treated females and their fetuses were evaluated at approximately 14 days after copulation. For the male dominant lethal phase, treated males cohabited with untreated femal (during 5 days of each week for 10 weeks) and females were sacrificed for fetal evaluation 14 days after the midweek of cohabitation during each of the 10 weeks. The appearance and behavior of the rats were unremarkable throughout the experiment and there were no treatment-related deaths. Growth rates were reduced in both female and male rats treated with 0.50 mg/kg HD. Indicators of reproductive performance did not demonstrate significant female dominant lethal effects, although significant male dominant lethal effects were observed at 2 and 3 week post-exposure. These effects included increases of early fetal resorptions and preimplantation losses and decreases of total live embryo implants. These effects were most consistently observed at a dose of 0.50 mg/kg, but frequently occurred at the lower doses. Although no treatment-related effects on male reproductive organ weights or sperm motility were found, a significant increase in the percentage of abnormal sperm was detected in males exposed to 0. 50 mg/kg HD. The timing of these effects is consistent with an effect during the

  4. Repair of potentially lethal damage by introduction of T4 DNA ligase in eucaryotic cells

    International Nuclear Information System (INIS)

    Durante, M.; Grossi, G.F.; Napolitano, M.; Gialanella, G.

    1991-01-01

    The bacterial enzyme PvuII, which generates blunt-ended DNA double-strand breaks, and T4 DNA ligase, which seals adjacent DNA fragments in coupling to ATP cleavage, were introduced in mouse C3H10T1/2 fibroblasts using osmolytic shock of pinocytic vesicles. Cells were then assayed for their clonogenic ability. In agreement with previous studies by others, the authors found that PvuII restriction endonuclease simulates ionizing radiation effects by causing a dose-dependent loss of reproductive capacity. They show that concomitant treatment with DNA ligase considerably increases cell survival. Survival curves were shown to be dependent on ligase enzyme dose and on ATP concentration in the hypertonic medium. They conclude that T4 DNA ligase is able to repair some potentially lethal damage produced by restriction endonucleases in eucaryotic cells. (author)

  5. Repair of sublethal damage in mammalian cells irradiated at ultrahigh dose rates

    International Nuclear Information System (INIS)

    Gerweck, L.E.; Epp, E.R.; Michaels, H.B.; Ling, C.C.; Peterson, E.C.

    1979-01-01

    The lethal response of asynchronous Chinese hamster ovary (CHO) cells exposed to single and split doses of radiation at conventional or ultrahigh dose rates has been examined to determine whether repair of sublethal damage occurs in cells irradiated at ultrahigh dose rates. The high-intensity irradiations were performed with electrons delivered in single 3-nsec pulses from a 600-kV field emission source under medium-removed, thin-layer conditions. Conventional dose-rate experiments were done under identical thin-layer conditions with 50-kVp x rays, or under full-medium conditions with 280-kVp x rays. Oxygenated cells were irradiated and maintained at 22 to 24 0 C between exposures. Survival did not increase as the time between two doses of pulsed electrons increased from 0 to 4 min, indicating no evidence of fast repair. However, increased survival was observed when 30 to 90 min was allowed to elapse between the split doses. The half-time for maximum repair was approx. = 30 min irrespective of the exposure conditions and radiation modality used. Observed repair ratios increased from approx. = 2 to 4 as the single-dose surviving fraction decreased from 10 -2 to 5 x 10 -4 . Over this survival range the repair ratios, measured at the same value of surviving fraction, were independent of dose rate. The observed repair ratios imply that the shoulder regions of the nonfractionated x-ray and pulsed-electron survival curves were not completely restored between the split doses. However, the fraction of the shoulder restored between split doses of radiation was dose-rate-independent. It is concluded that sublethal damage can be repaired in oxygenated CHO cells irradiated at dose rates of the order of 10 11 rad/sec

  6. SU-E-T-179: Exploring Appropriate Offset Values for Pencil Beam and Monte Carlo Dose Optimization in Lung Stereotactic Body Radiotherapy Encompassing the Effects of Respiration and Tumor Location

    Energy Technology Data Exchange (ETDEWEB)

    Evans, G [Boca Raton, FL (United States); Shang, C [Florida Atlantic University, Boca Raton, FL (United States); Leventouri, T [Lynn Cancer Institute, Boca Raton, FL (United States)

    2014-06-01

    Purpose: Exploring appropriate offset values in dose optimization with pencil beam (PB) algorithm to minimize dosimetric differences with plans calculated with Monte Carlo (MC) for lung cancer treatment with Stereotactic Body Radiotherapy (SBRT). Methods: 20 cases of Non-Small Cell Lung Cancer, treated with gated full motion range SBRT were selected. According to the proximity of the Gross Tumor Volume (GTV) to the chest wall, two groups are defined: peripherally located when GTV merges with the chest wall for at least 50% of the lesion diameter, and centrally located when the GTV is surrounded by lung tissue. Treatment plans were created on 4D average intensity projection (AIP) CT set with Brainlab iPlanDose 4.1.2 planning system. The D97 of PTV was normalized to 50Gy using the fast PB and compared with MC. The optimized plan was then recomputed over each 4D respiratory phase, and compared with MC using the same plan MU's. Results: The mean difference in the PB and MC D97 of the ITV was 10.5% (±0.8%) of the prescription dose (50Gy). PB algorithm showed 2.3–2.4% less overestimation to the D97 of the ITV, when comparing to MC, in the maximum exhalation phase than in the maximal inhalation phase. Significantly smaller dose difference between PB and MC is also shown in plans for peripheral lesions (7.7 ± 0.7%) versus for central lesions (12.7±0.8%) (p< 0.01). Conclusion: The dosimetric differences between PB and MC can be reasonably predicted depending on the location of lesion in the lung, and may be used as offset value in dose optimization with PB. Since the maximal exhalation phase demonstrates less dose discrepancy between the two algorithms than that in maximal inhalation phase, caution is suggested when the latter is included as a major phase portion in the respiration gated lung SBRT.

  7. Value of image fusion using single photon emission computed tomography with integrated low dose computed tomography in comparison with a retrospective voxel-based method in neuroendocrine tumours

    International Nuclear Information System (INIS)

    Amthauer, H.; Denecke, T.; Ruf, J.; Gutberlet, M.; Felix, R.; Lemke, A.J.; Rohlfing, T.; Boehmig, M.; Ploeckinger, U.

    2005-01-01

    The objective was the evaluation of single photon emission computed tomography (SPECT) with integrated low dose computed tomography (CT) in comparison with a retrospective fusion of SPECT and high-resolution CT and a side-by-side analysis for lesion localisation in patients with neuroendocrine tumours. Twenty-seven patients were examined by multidetector CT. Additionally, as part of somatostatin receptor scintigraphy (SRS), an integrated SPECT-CT was performed. SPECT and CT data were fused using software with a registration algorithm based on normalised mutual information. The reliability of the topographic assignment of lesions in SPECT-CT, retrospective fusion and side-by-side analysis was evaluated by two blinded readers. Two patients were not enrolled in the final analysis because of misregistrations in the retrospective fusion. Eighty-seven foci were included in the analysis. For the anatomical assignment of foci, SPECT-CT and retrospective fusion revealed overall accuracies of 91 and 94% (side-by-side analysis 86%). The correct identification of foci as lymph node manifestations (n=25) was more accurate by retrospective fusion (88%) than from SPECT-CT images (76%) or by side-by-side analysis (60%). Both modalities of image fusion appear to be well suited for the localisation of SRS foci and are superior to side-by-side analysis of non-fused images especially concerning lymph node manifestations. (orig.)

  8. An environmental dose experiment

    Science.gov (United States)

    Peralta, Luis

    2017-11-01

    Several radiation sources worldwide contribute to the delivered dose to the human population. This radiation also acts as a natural background when detecting radiation, for instance from radioactive sources. In this work a medium-sized plastic scintillation detector is used to evaluate the dose delivered by natural radiation sources. Calibration of the detector involved the use of radioactive sources and Monte Carlo simulation of the energy deposition per disintegration. A measurement of the annual dose due to background radiation to the body was then estimated. A dose value compatible with the value reported by the United Nations Scientific Committee on the Effects of Atomic Radiation was obtained.

  9. An environmental dose experiment

    International Nuclear Information System (INIS)

    Peralta, Luis

    2017-01-01

    Several radiation sources worldwide contribute to the delivered dose to the human population. This radiation also acts as a natural background when detecting radiation, for instance from radioactive sources. In this work a medium-sized plastic scintillation detector is used to evaluate the dose delivered by natural radiation sources. Calibration of the detector involved the use of radioactive sources and Monte Carlo simulation of the energy deposition per disintegration. A measurement of the annual dose due to background radiation to the body was then estimated. A dose value compatible with the value reported by the United Nations Scientific Committee on the Effects of Atomic Radiation was obtained. (paper)

  10. A novel highly reproducible and lethal nonhuman primate model for orthopox virus infection.

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    Marit Kramski

    Full Text Available The intentional re-introduction of Variola virus (VARV, the agent of smallpox, into the human population is of great concern due its bio-terroristic potential. Moreover, zoonotic infections with Cowpox (CPXV and Monkeypox virus (MPXV cause severe diseases in humans. Smallpox vaccines presently available can have severe adverse effects that are no longer acceptable. The efficacy and safety of new vaccines and antiviral drugs for use in humans can only be demonstrated in animal models. The existing nonhuman primate models, using VARV and MPXV, need very high viral doses that have to be applied intravenously or intratracheally to induce a lethal infection in macaques. To overcome these drawbacks, the infectivity and pathogenicity of a particular CPXV was evaluated in the common marmoset (Callithrix jacchus.A CPXV named calpox virus was isolated from a lethal orthopox virus (OPV outbreak in New World monkeys. We demonstrated that marmosets infected with calpox virus, not only via the intravenous but also the intranasal route, reproducibly develop symptoms resembling smallpox in humans. Infected animals died within 1-3 days after onset of symptoms, even when very low infectious viral doses of 5x10(2 pfu were applied intranasally. Infectious virus was demonstrated in blood, saliva and all organs analyzed.We present the first characterization of a new OPV infection model inducing a disease in common marmosets comparable to smallpox in humans. Intranasal virus inoculation mimicking the natural route of smallpox infection led to reproducible infection. In vivo titration resulted in an MID(50 (minimal monkey infectious dose 50% of 8.3x10(2 pfu of calpox virus which is approximately 10,000-fold lower than MPXV and VARV doses applied in the macaque models. Therefore, the calpox virus/marmoset model is a suitable nonhuman primate model for the validation of vaccines and antiviral drugs. Furthermore, this model can help study mechanisms of OPV pathogenesis.

  11. Retrospective analysis of insulin responses to standard dosed oral glucose tests (OGTs) via naso-gastric tubing towards definition of an objective cut-off value.

    Science.gov (United States)

    Warnken, Tobias; Delarocque, Julien; Schumacher, Svenja; Huber, Korinna; Feige, Karsten

    2018-01-19

    Insulin dysregulation (ID) with basal or postprandial hyperinsulinemia is one of the key findings in horses and ponies suffering from the equine metabolic syndrome (EMS). Assessment of ID can easily be performed in clinical settings by the use of oral glucose challenge tests. Oral glucose test (OGT) performed with 1 g/kg bodyweight (BW) glucose administered via naso-gastric tube allows the exact administration of a defined glucose dosage in a short time. However, reliable cut-off values have not been available so far. Therefore, the aim of the study was to describe variations in insulin response to OGT via naso-gastric tubing and to provide a clinical useful cut-off value for ID when using the insulin quantification performed with an equine-optimized insulin enzyme-linked immunosorbent assay. Data visualization revealed no clear separation in the serum insulin concentration of insulin sensitive and insulin dysregulated horses during OGT. Therefore, a model based clustering method was used to circumvent the use of an arbitrary limit for categorization. This method considered all data-points for the classification, taking into account the individual insulin trajectory during the OGT. With this method two clusters were differentiated, one with low and one with high insulin responses during OGT. The cluster of individuals with low insulin response was consistently detected, independently of the initialization parameters of the algorithm. In this cluster the 97.5% quantile of insulin is 110 µLU/mL at 120 min. We suggest using this insulin concentration of 110 µLU/mL as a cut-off value for samples obtained at 120 min in OGT. OGT performed with 1 g/kg BW glucose and administration via naso-gastric tubing can easily be performed under clinical settings. Application of the cut-off value of 110 µLU/mL at 120 min allows assessment of ID in horses.

  12. A single cidofovir treatment rescues animals at progressive stages of lethal orthopoxvirus disease

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    Israely Tomer

    2012-06-01

    Full Text Available Abstract Background In an event of a smallpox outbreak in humans, the window for efficacious treatment by vaccination with vaccinia viruses (VACV is believed to be limited to the first few days post-exposure (p.e.. We recently demonstrated in a mouse model for human smallpox, that active immunization 2–3 days p.e. with either VACV-Lister or modified VACV Ankara (MVA vaccines, can rescue animals from lethal challenge of ectromelia virus (ECTV, the causative agent of mousepox. The present study was carried out in order to determine whether a single dose of the anti-viral cidofovir (CDV, administered at different times and doses p.e. either alone or in conjunction with active vaccination, can rescue ECTV infected mice. Methods Animals were infected intranasally with ECTV, treated on different days with various single CDV doses and monitored for morbidity, mortality and humoral response. In addition, in order to determine the influence of CDV on the immune response following vaccination, both the "clinical take”, IFN-gamma and IgG Ab levels in the serum were evaluated as well as the ability of the mice to withstand a lethal challenge of ECTV. Finally the efficacy of a combined treatment regime of CDV and vaccination p.e. was determined. Results A single p.e. CDV treatment is sufficient for protection depending on the initiation time and dose (2.5 – 100 mg/kg of treatment. Solid protection was achieved by a low dose (5 mg/kg CDV treatment even if given at day 6 p.e., approximately 4 days before death of the control infected untreated mice (mean time to death (MTTD 10.2. At the same time point complete protection was achieved by single treatment with higher doses of CDV (25 or 100 mg/kg. Irrespective of treatment dose, all surviving animals developed a protective immune response even when the CDV treatment was initiated one day p.e.. After seven days post treatment with the highest dose (100 mg/kg, virus was still detected in some

  13. Lethal and sublethal responses to a sediment bound toxicant by two oligochaetes from Lake Michigan: stylodrilus heringianus and limnodrilus hoffmeisteri

    International Nuclear Information System (INIS)

    Keilty, T.J.

    1987-01-01

    Short-term lethal, and short and long-term sublethal responses by Stylodrilus heringianus (Lumbriculidae) and Limnodrilus hoffmeisteri (Tubificidae) to sediments dosed with endrin were measured in single and mixed species tests. Ninety-six hour LC 50 values were 2588 +/- 1974 and 2757 +/- 995 ug/g dry weight sediment for S. heringianus and L. hoffmeisteri respectively. Ninety-six hour EC 50 burrowing avoidance values (concentration where 50% do not burrow) were one to two orders of magnitude lower than the LC 50 's. Short-term mixed species LC 50 data suggested that L. hoffmeisteri may benefit from the presence of S. heringianus. Long-term sublethal responses were quantified by measuring sediment reworking rates (the rate at which subsurface sediments are egested at the surface and re-buried) in laboratory microcosms. Rates were determined by monitoring a gamma-emitting 137 Cesium marker layer with a well-collimated NaI detector. Sediment endrin concentrations ranged from 3 ng/g to 82 ug/g in six 1300 hour experiments. For S. heringianus, reworking rates were stimulated at low concentrations during the first half of experiments, followed by gradual decreases relative to controls. Stimulation of L. hoffmeisteri reworking was not observed. At high concentrations, early reworking rates were reduced for both species, followed by dramatic decreases later on. In mixed species experiments at high concentrations, the presence of S. heringianus enhanced the reworking of L. hoffmeisteri, although the reverse was not observed. Decreased mortality and increased post experimental dry weights of L. hoffmeisteri in mixed, relative to single species tests were also observed. Generally, post experimental worm weights were inversely related to sediment endrin loads, and bioconcentration factors for S. heringianus (10-40) were approximately fourfold that of L. hoffmeisteri (1-10)

  14. Dose measurements in mammography

    International Nuclear Information System (INIS)

    Kainberger, F.; Kallinger, W.

    1977-01-01

    Dose measurements at the mamma during mammography were carried out in the form of direct measurement with thermoluminescent dosimetry. Measurement was done for the in- and outcoming doses at the mamma, the dose exposure of the sternal region and the scattered rays above the symphysis, the latter as parameter for the genetic radiation exposure. As expected, the dose of the smooth radiation used for mammography showed a strong decrease at the outcome point in comparison with the income point. Surprisingly high was the scattered radiation in the sternal region. A corresponding protection by lead plates could be taken into consideration. Extremely low is the scattered radiation above the symphysis. Even measurements with the very sensitive calcium fluoride dosimeters did not reveal any practically important dose in the symphysis region. Most measurement values remained below the determinable dose of 0.3mR. Some maximal values varied in the range of 3-1 mR. (orig.) [de

  15. Effects of lethal and non-lethal malaria on the mononuclear phagocyte system

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Tosta

    1983-03-01

    Full Text Available The effects ofone non-lethal species ofmalarialparasite, Plasmodium yoelii, and one lethal species, P. berghei, on the mononuclear phagocyte system (MPS of BALB/c mice were studied. P. yoelii caused a greater and more sustained expansion and activation of the MPS, and the two major populations of spleen phagocytic cells-red pulp and marginal zone macrophages - exhibited a greater increase in numbers in this infection. During the course of P. berghei mataria, the spleen was progressively occupied by haematopoietic tissue and, at the terminal stage of infection, an extensive depletion of lymphocytes and macrophages was apparent. The possibility was suggested that the outcome of mataria may be inftuenced by the particular way the parasite interacts with the MPS.Estudou-se o efeito da infecção causada por espécie letal (Plasmodium berghei e não- letal (P. yoelii de plasmódio sobre o sistema de fagócitos mononucleares de camundongo BALB/c. O P. yoelii causou maior e mais prolongada expansão e ativação do sistema de macrófagos. As duas mais importantes populações de fagócitos esplênicos - macrófagos de polpa vermelha e da zona marginal - exibiam maior aumento do número de células nesta infecção. Durante a evolução da malária por P. berghei, o baço foi progressivamente ocupado por tecido hematopoiético e, na fase terminal da infecção, observou-se significativa depleção dos linfócitos e macrófagos esplênicos. Os dados apresentados indicam que a evolução da malária depende do tipo de interação entre o plasmódio e o sistema de fagócitos mononucleares.

  16. The Effects of Anthrax Lethal Toxin on Host Barrier Function

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    David M. Frucht

    2011-06-01

    Full Text Available The pathological actions of anthrax toxin require the activities of its edema factor (EF and lethal factor (LF enzyme components, which gain intracellular access via its receptor-binding component, protective antigen (PA. LF is a metalloproteinase with specificity for selected mitogen-activated protein kinase kinases (MKKs, but its activity is not directly lethal to many types of primary and transformed cells in vitro. Nevertheless, in vivo treatment of several animal species with the combination of LF and PA (termed lethal toxin or LT leads to morbidity and mortality, suggesting that LT-dependent toxicity is mediated by cellular interactions between host cells. Decades of research have revealed that a central hallmark of this toxicity is the disruption of key cellular barriers required to maintain homeostasis. This review will focus on the current understanding of the effects of LT on barrier function, highlighting recent progress in establishing the molecular mechanisms underlying these effects.

  17. Occupational dose constraint

    International Nuclear Information System (INIS)

    Heilbron Filho, Paulo Fernando Lavalle; Xavier, Ana Maria

    2005-01-01

    The revision process of the international radiological protection regulations has resulted in the adoption of new concepts, such as practice, intervention, avoidable and restriction of dose (dose constraint). The latter deserving of special mention since it may involve reducing a priori of the dose limits established both for the public and to individuals occupationally exposed, values that can be further reduced, depending on the application of the principle of optimization. This article aims to present, with clarity, from the criteria adopted to define dose constraint values to the public, a methodology to establish the dose constraint values for occupationally exposed individuals, as well as an example of the application of this methodology to the practice of industrial radiography

  18. Early events of lethal action by tobramycin in Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Raulston, J.E.

    1988-01-01

    The immediate activities of the aminoglycoside antibiotic, tobramycin, were investigated in Pseudomonas aeruginosa PAO1. The influence of carbon growth substate and the antibiotic exposure environment in the magnitude of activity were examined. Lethality by 8 μg/ml tobramycin occurred rapidly (1 to 3 minutes). The release of specific cellular components into the supernatant was associated with lethality. This material was initially detected as an increase in UV-absorbance. Magnesium in the reaction mixture provided protection against lethality and leakage, but did not reverse lethal damage after a 3 minute tobramycin treatment. Also, uptake of 3 H-tobramycin was reduced in the presence of magnesium. Cells grown with glucose as a carbon source were more susceptible than organic acid grown cells as was the rapidity and amount of cell damage. Analyses of the leakage material revealed a 2-fold increase of protein in the supernatant after a 1-3 minute treatment which paralleled lethality. A prominent 29 kDa protein was observed by SDS-PAGE in the released material, which has been identified as the periplasmic enzyme, β-lactamase. The immediate activities of tobramycin did not involve (i) release of overall cell protein, (ii) massive loss of total pool amino acids, (iii) cell lysis, (iv) inhibition of proline uptake, (v) release of lipopolysaccharide, or (vi) leakage of ATP. Electron microscopy showed no apparent damage after a 3 minute exposure. 40% inhibition of protein synthesis had occurred by 3 minutes of exposure, while release of UV-absorbing material and lethality were detectable after only 1 minute. Resistant cystic fibrosis isolates of P. aeruginosa did not leak under the same experimental conditions, but one of two susceptible strains examined did show increased UV-absorbance following treatment

  19. Impact of acute alcohol consumption on lethality of suicide methods.

    Science.gov (United States)

    Park, C Hyung Keun; Yoo, Seong Ho; Lee, Jaewon; Cho, Sung Joon; Shin, Min-Sup; Kim, Eun Young; Kim, Se Hyun; Ham, Keunsoo; Ahn, Yong Min

    2017-05-01

    The influence of acute alcohol consumption on the factors related to suicide remains understudied. Thus, the present study investigated the relationship between blood alcohol content (BAC) and the lethality of suicide methods. Autopsy data on 315 South Korean suicide completers with a positive BAC were collected from a nationwide pool between May 2015 and November 2015, and the methods were dichotomised as suicide methods of low lethality (SMLL; drug/chemical overdose and sharp objects, n=67) and suicide methods of high lethality (SMHL; everything else, n=243). BAC at the time of autopsy and various suicide-related factors of these two groups were compared with logistic regression analyses. Compared to suicide completers with a BAC in the lowest range of 0.011-0.049%, suicide completers with a BAC in the range of 0.150-0.199% were more likely to use SMHL (odds ratio [OR]: 3.644, 95% confidence interval [CI]: 1.221-10.874). Additionally, the adoption of SMHL was significantly associated with the absence of a psychiatric illness (OR: 0.433, 95% CI: 0.222-0.843) and a younger age; the OR for high BAC among subjects in their 40s was 0.266 (95% CI: 0.083-0.856); in their 50s, 0.183 (95% CI: 0.055-0.615); and in their 60s, 0.057 (95% CI: 0.015-0.216). The relationship between BAC and suicide method lethality was represented by a bell-shaped pattern in which suicide methods of high lethality were more likely to be used by suicide completers with mid-range BAC levels. The increased impulsivity and impairments in particular executive functions, including planning and organization, associated with acute alcohol use may influence the selection of a particular suicide method based on its lethality. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Ecstasy tablets intoxication with lethal autcome

    Directory of Open Access Journals (Sweden)

    Đorđević Snežana

    2007-01-01

    Full Text Available Background. Ecstasy, 3,4-methylenedioxymethamphetamine (MDMA, is a synthetic compound increasingly popular as a recreational drug. Tablets known as ecstasy contain MDMA, but may also contain caffeine, ephedrine, paramethoxyamphetamine, 3,4-methylenedioxyamphetamine (MDA, amphetamine, methamphetamine, and ketamine. After absorption MDMA is metabolized to MDA, 4-hydroxy-3- metoxymetamphetamine (HMMA and 4-hydroxy-3- metoxyamphetamine (HMA. After that HMMA and HMA are conjugated and excreted by urine. The aim of this report was to confirm by toxicological post mortem analyses of poisoned person organs that ecstasy had been the cause of his death. Case report. We reported the death of a 17-year-old boy after the ingestion of ecstasy. MDMA and metabolites were determined by multicolumn high performance liquid chromatography with UV spectral detection (HPLC-UV. Toxicological tests showed the presence of MDMA in all samples. When examining post mortem material (the organs, the highest concentrations were measured in the stomach (835,97 μg/g and kidney (801,14 μg/g. The minimal concentration was in the liver (22,26 μg/g. Conclusion. The obtained results of MDMA and its metabolites concentrations showed abuse of a high dose of ecstasy. .

  1. Lethal and Mutagenic Effects of Tritium Decay Produced by Tritiated Compounds Incorporated into Bacteria and Bacteriophages

    Energy Technology Data Exchange (ETDEWEB)

    Person, S. [Pennsylvania State University, University Park, PA (United States)

    1968-06-15

    The work discussed below is predominantly from the author's laboratory. Some effects of tritium decay on bacteria and bacteriophages, using labelled compounds that are incorporated preferentially into DNA, RNA or protein, have been studied. A relatively high killing efficiency, the probability that a single decay produces loss of colony-forming ability in bacteria or loss of plaque-forming ability in bacteriophages, is observed for thymidine- methyl-{sup 3}H decay, but this is thought to be due to S-particle ionization damage. The most definitive experiments involved a comparison of killing efficiencies for decays originating as thymidine-methyl-{sup 3}H in phage DNA and as amino acid-{sup 3}H in phage protein with the calculated {beta}-particle path length through, the DNA in the two cases. Experimental and calculated values are essentially the same. Radiation-dose calculations to many different bacterial sub-volumes were determined for several different distributions of radioactivity. The high killing efficiency for thymidine-methyl- {sup 3}H decay can be explained by {beta}-particle ionizations, providing DNA is the sensitive target molecule and it is organized in a central volume of the cell (see also Ref.[24]). Although both the lethal and mutagenic effect of thymidine-methyl-{sup 3}H and amino acid-{sup 3}H decays can readily be explained on the basis of {beta}-particle ionizations, the observed large mutation frequency produced by uracil-5{sup 3}H decay cannot. The majority of mutations produced by uracil-5{sup 3}H decays are due to a specific chemical rearrangement of the parent molecule, since decays from uracil-6{sup 3}H are 6 to 7-fold less mutagenic. It is clear that the decays leading to mutations for cells labelled with uracil-5{sup 3}H originate as cytosine-5{sup 3}H in bacterial DNA. Recent work shows that the specific chemical rearrangement causes a C --> T(u) genetic coding change. (author)

  2. Lethals induced by γ-radiation in drosophila somatic cells

    International Nuclear Information System (INIS)

    Ivanov, A.I.

    1989-01-01

    Exposure of 3-hour drosophila male embryos to γ-radiation during the topographic segregation of the germ anlage nuclei caused recessive sex-linked lethals in somatic cells only. The selectivity of the screening was determined by the ratio of mutation frequencies induced in embryos and adult males. Analysis of lethal mutations shows that a minimal rate of the divergence between germinal and somatic patterns of the cell development is observed in the embryogenesis, the 3d instar larva and prepupa, and maximal in the 1st and 2nd larva and pupa

  3. Effective lethal mutagenesis of influenza virus by three nucleoside analogs.

    Science.gov (United States)

    Pauly, Matthew D; Lauring, Adam S

    2015-04-01

    Lethal mutagenesis is a broad-spectrum antiviral strategy that exploits the high mutation rate and low mutational tolerance of many RNA viruses. This approach uses mutagenic drugs to increase viral mutation rates and burden viral populations with mutations that reduce the number of infectious progeny. We investigated the effectiveness of lethal mutagenesis as a strategy against influenza virus using three nucleoside analogs, ribavirin, 5-azacytidine, and 5-fluorouracil. All three drugs were active against a panel of seasonal H3N2 and laboratory-adapted H1N1 strains. We found that each drug increased the frequency of mutations in influenza virus populations and decreased the virus' specific infectivity, indicating a mutagenic mode of action. We were able to drive viral populations to extinction by passaging influenza virus in the presence of each drug, indicating that complete lethal mutagenesis of influenza virus populations can be achieved when a sufficient mutational burden is applied. Population-wide resistance to these mutagenic agents did not arise after serial passage of influenza virus populations in sublethal concentrations of drug. Sequencing of these drug-passaged viral populations revealed genome-wide accumulation of mutations at low frequency. The replicative capacity of drug-passaged populations was reduced at higher multiplicities of infection, suggesting the presence of defective interfering particles and a possible barrier to the evolution of resistance. Together, our data suggest that lethal mutagenesis may be a particularly effective therapeutic approach with a high genetic barrier to resistance for influenza virus. Influenza virus is an RNA virus that causes significant morbidity and mortality during annual epidemics. Novel therapies for RNA viruses are needed due to the ease with which these viruses evolve resistance to existing therapeutics. Lethal mutagenesis is a broad-spectrum strategy that exploits the high mutation rate and the low

  4. An antivector vaccine protects against a lethal vector-borne pathogen.

    Directory of Open Access Journals (Sweden)

    Milan Labuda

    2006-04-01

    Full Text Available Vaccines that target blood-feeding disease vectors, such as mosquitoes and ticks, have the potential to protect against the many diseases caused by vector-borne pathogens. We tested the ability of an anti-tick vaccine derived from a tick cement protein (64TRP of Rhipicephalus appendiculatus to protect mice against tick-borne encephalitis virus (TBEV transmitted by infected Ixodes ricinus ticks. The vaccine has a "dual action" in immunized animals: when infested with ticks, the inflammatory and immune responses first disrupt the skin feeding site, resulting in impaired blood feeding, and then specific anti-64TRP antibodies cross-react with midgut antigenic epitopes, causing rupture of the tick midgut and death of engorged ticks. Three parameters were measured: "transmission," number of uninfected nymphal ticks that became infected when cofeeding with an infected adult female tick; "support," number of mice supporting virus transmission from the infected tick to cofeeding uninfected nymphs; and "survival," number of mice that survived infection by tick bite and subsequent challenge by intraperitoneal inoculation of a lethal dose of TBEV. We show that one dose of the 64TRP vaccine protects mice against lethal challenge by infected ticks; control animals developed a fatal viral encephalitis. The protective effect of the 64TRP vaccine was comparable to that of a single dose of a commercial TBEV vaccine, while the transmission-blocking effect of 64TRP was better than that of the antiviral vaccine in reducing the number of animals supporting virus transmission. By contrast, the commercial antitick vaccine (TickGARD that targets only the tick's midgut showed transmission-blocking activity but was not protective. The 64TRP vaccine demonstrates the potential to control vector-borne disease by interfering with pathogen transmission, apparently by mediating a local cutaneous inflammatory immune response at the tick-feeding site.

  5. [Underlying Mechanisms of Methamphetamine-Induced Self-Injurious Behavior and Lethal Effects in Mice].

    Science.gov (United States)

    Mori, Tomohisa; Sawaguchi, Toshiko

    2018-01-01

    Relatively high doses of psychostimulants induce neurotoxicity on the dopaminergic system and self-injurious behavior (SIB) in rodents. However the underlying neuronal mechanisms of SIB remains unclear. Dopamine receptor antagonists, N-methyl-D-aspartic acid (NMDA) receptor antagonists, Nitric Oxide Synthase (NOS) inhibitors and free radical scavengers significantly attenuate methamphetamine-induced SIB. These findings indicate that activation of dopamine as well as NMDA receptors followed by radical formation and oxidative stress, especially when mediated by NOS activation, is associated with methamphetamine-induced SIB. On the other hand, an increase in the incidence of polydrug abuse is a major problem worldwide. Coadministered methamphetamine and morphine induced lethality in more than 80% in mice, accompanied by an increase in the number of poly (ADP-ribose) polymerase (PARP)-immunoreactive cells in the heart, kidney and liver. The lethal effect and the increase in the incidence of rupture or PARP-immunoreactive cells induced by the coadministration of methamphetamine and morphine were significantly attenuated by pretreatment with a phospholipase A2 inhibitor or a radical scavenger, or by cooling of body from 30 to 90 min after drug administration. These results suggest that free radicals play an important role in the increased lethality induced by the coadministration of methamphetamine and morphine. Therefore, free radical scavengers and cooling are beneficial for preventing death that is induced by the coadministration of methamphetamine and morphine. These findings may help us better understand for masochistic behavior, which is a clinical phenomenon on SIB, as well as polydrug-abuse-induced acute toxicity.

  6. Phytochemistry, Brine shrimp lethality and mice acute oral toxicity studies on seed extracts of Vernonia anthelmintica.

    Science.gov (United States)

    Jamil, Subia; Khan, Rafeeq Alam; Afroz, Syeda; Ahmed, Shadab

    2016-11-01

    Despite the widespread use of Vernonia anthelmintica seeds in traditional medicine, the need to establish the safety of the Vernonia anthelmintica is required to ascertain the safe use of this herbal medicine. The aim of the present study is to establish the acute toxicity profile of different extracts of Vernonia anthelmintica. Hexane and ethanol extract of Vernonia Anthelmintica has been studied for its brine shrimp lethality potential. Water decoction (WDVA), Hexane (HEVA) and Ethanol (EEVA) extracts of Vernonia anthelmintica has also been evaluated for their in-vivo acute oral toxicity in mice by Lorke's method. Phytochemistry of all three extracts was also evaluated for the presence of their secondary metabolites. All three extracts showed the presence of flavonoids and terpenoids, while alkaloids, tannins and fixed oils were present in HEVA and EEVA. Furthermore EEVA also showed presence of carbohydrates and HEVA also showed the presence of cardiac glycosides. Ethanol and hexane extracts of Vernonia anthelmintica showed a positive cytotoxicity in brine shrimp lethality test at 24 hours with LC50 104.16 (224.0-48.05)μg/ml and 216.11μg/ml (378.2-128.7) respectively as compared to standard drug etoposide LC50 7.46μg/ml. The oral LD50 for EEVA, HEVA and WDVA in mice by Lorke's method was greater than 5000mg/kg. The result of brine shrimp lethality test clearly exhibited the presence of bioactive compounds with cytotoxic potential; however seems to be safe for oral use since LD50 was higher than 5000mg/kg and thus safety of acute dosing in vivo practices is justified.

  7. A hepatic protein, fetuin-A, occupies a protective role in lethal systemic inflammation.

    Directory of Open Access Journals (Sweden)

    Wei Li

    2011-02-01

    Full Text Available A liver-derived protein, fetuin-A, was first purified from calf fetal serum in 1944, but its potential role in lethal systemic inflammation was previously unknown. This study aims to delineate the molecular mechanisms underlying the regulation of hepatic fetuin-A expression during lethal systemic inflammation (LSI, and investigated whether alterations of fetuin-A levels affect animal survival, and influence systemic accumulation of a late mediator, HMGB1.LSI was induced by endotoxemia or cecal ligation and puncture (CLP in fetuin-A knock-out or wild-type mice, and animal survival rates were compared. Murine peritoneal macrophages were challenged with exogenous (endotoxin or endogenous (IFN-γ stimuli in the absence or presence of fetuin-A, and HMGB1 expression and release was assessed. Circulating fetuin-A levels were decreased in a time-dependent manner, starting between 26 h, reaching a nadir around 24-48 h, and returning towards base-line approximately 72 h post onset of endotoxemia or sepsis. These dynamic changes were mirrored by an early cytokine IFN-γ-mediated inhibition (up to 50-70% of hepatic fetuin-A expression. Disruption of fetuin-A expression rendered animals more susceptible to LSI, whereas supplementation of fetuin-A (20-100 mg/kg dose-dependently increased animal survival rates. The protection was associated with a significant reduction in systemic HMGB1 accumulation in vivo, and parallel inhibition of IFN-γ- or LPS-induced HMGB1 release in vitro.These experimental data suggest that fetuin-A is protective against lethal systemic inflammation partly by inhibiting active HMGB1 release.

  8. A chimeric measles virus with canine distemper envelope protects ferrets from lethal distemper challenge.

    Science.gov (United States)

    Rouxel, Ronan Nicolas; Svitek, Nicholas; von Messling, Veronika

    2009-08-06

    CDV infects a broad range of carnivores, and over the past decades it has caused outbreaks in a variety of wild carnivore populations. Since the currently available live-attenuated vaccine is not sufficiently safe in these highly susceptible species, we produced a chimeric virus combining the replication complex of the measles Moraten vaccine strain with the envelope of a recent CDV wild type isolate. The resulting virus did not cause disease or immunosuppression in ferrets and conferred protection from challenge with a lethal wild type strain, demonstrating its potential value for wildlife conservation efforts.

  9. Megakaryocytopoiesis and the number of thrombocytes after bone marrow cell transplantation in lethally irradiated mice

    International Nuclear Information System (INIS)

    Viktora, L.; Hermanova, E.; Zoubkova, M.

    1977-01-01

    Changes were studied in the number of thrombocytes in the peripheral blood and megakaryocytes in the bone marrow and spleen in lethally irradiated mice after the transplantation of bone marrow cells. It was found that the thrombocytes increased in dependence on time after transplantation with the maximal values around the 20th day. An increased megakaryocytopoiesis was observed not only in the bone marrow but also in the spleen. These ascertainments suggest the importance of the transplantation of bone marrow cells and the role of thrombocytes for the survival of the organism after irradiation. (author)

  10. Quantitative determination of the contribution of indirect and direct radiation action to the production of lethal lesions in mammalian cells

    International Nuclear Information System (INIS)

    Pohlit, W.; Drenkard, S.

    1985-01-01

    For quantitative models of radiation action in living cells it is necessary to know what fraction of the absorbed dose affects the target molecule by direct radiation action and what fraction by indirect radiation action. Mammalian cells were irradiated in suspension, saturated with N 2 O or CO 2 . With these gases the production of OH-radicals is changed by a factor of two in aqueous solutions and a corresponding change in cell survival would be expected, if only indirect radiation action is involved in the production of lethal lesions in the living cell. No difference could be detected, however, and it is concluded that indirect radiation action does not contribute to radiation lethality in mammalian cells. (author)

  11. Postirradiation expression of lethal mutations in an immortalized human keratinocyte cell line

    International Nuclear Information System (INIS)

    O'Reilly, S.; Mothersill, C.; Seymour, C.B.

    1994-01-01

    The quantification of the extent of delayed cell death and the rate and pattern of its occurrence in relation to the cell division cycle is important in radiotherapy and also in radiation transformation studies related to protection and dose limits. Here the numbers of lethal mutations occurring over 45 population doublings (clonal expansion to about 10 13 cells per cell originally surviving irradiation) was measured in an HPV 16 immortalized human keratinocyte cell lines used for transformation studies. The results showed that when postirradiation (dose range 1-6 Gy) growth curves were constructed, the difference in slopes could be accounted for entirely by correcting for the non-clonogenic fraction in the cell count, excluding a longer cell generation time as an explanation. When the cell loss was examined over the entire growth period of 6 weeks (about 45 doublings of the cell population), it was found to be dose dependent for the first two passages, but then to become more independent of dose. The results allow a time/cell generation dependent factor to be derived for the cell line and used in survival curve equations where effects of radiation are being measured at times distant from the original exposure. (author)

  12. Reactivation of Immunological Response in Lethally X-Irradiated Mice Treated with Isogeneic Bone Marrow

    Energy Technology Data Exchange (ETDEWEB)

    Stankovic, V.; Slijepcevic, M.; Hrsak, I. [Institute Ruder Boskovic, Zagreb, Yugoslavia (Croatia)

    1968-08-15

    Male and female C57BL/H and CBA/H mice aged 10-12 weeks were used as recipients and donors, respectively. All recipient mice were given a lethal whole-body X-irradiation dose (850 R for C57BL and 950 R for CBA mice) followed by iv injection of 10 x 106 isogeneic eosin-negative bone-marrow cells suspended in 0.5 ml of Hank's solution. The number of eosin-positive cells was less than 10%. The state of immunological responsiveness of irradiated recipients was measured at different time intervals up to 86 days after irradiation. The immune response to bacterial antigen was measured with the titre of agglutinating antibodies in serum six days after iv antigenic stimulation with a suspension of 2 x 10{sup 7} killed Salmonella typhimurium cells. The immune response to tissue antigens was evaluated by: (a) the effectiveness of the spleen cells from isologous radiation chimeric parental mice in preventing bone marrow from F{sub 1} (C57BL x CBA) hybrid donor from therapeutically affecting lethally irradiated F j recipient mice; (b) the effectiveness of the spleen cells in inducing splenom egaly in recipient F{sub 1} hybrid mice (Simonsen test). It was found that the responsiveness to bacterial antigens reappears much earlier and increases much faster than the immunological responsiveness to tissue antigens. (author)

  13. Lethal effects of solar radiation in proficient and deficient bacteria in repair systems

    International Nuclear Information System (INIS)

    Sousa Neto, A. de.

    1980-01-01

    A study of the lethal action of solar radiation on strains of E.coli K12, proficient or deficient in repair systems, as well as the wild type strain gene products are involved in repair of damage induced by solar radiation. The inactivation of the various bacterial strains (normalized to a dose equivalent to radiation at a wavelength 254 nm) suggests that the more energetic wavelengths of the solar spectrum (290-320 nm) could be responsible for the primary damage that occurs in the DNA. The reduction in the shoulder of the survival curve in wild type strains in indicative of induction of sub-lethal damage in this region of the curve. Analysing solar inactivation curves of the bacterial strains (normalised by spore dosimetry) together with those of the same strains irradiated with UV at 254 nm, it was evident that 254 nm is not the ideal wavelength for comparison. This analysis also indicated that in addition to damage to DNA, other factors are involved in the solar radiation inactivation of wild type strains. (author)

  14. Perforated appendicitis presenting as a thigh abscess: A lethal ...

    African Journals Online (AJOL)

    Typical cases of acute appendicitis have excellent treatment outcomes, if managed appropriately.1 We discuss an unusual case of perforated retrocaecal appendicitis that presented as a right thigh abscess without prominent abdominal symptoms, which highlights the lethal nature of advanced appendicitis even when ...

  15. Dominant-lethal mutations and heritable translocations in mice

    International Nuclear Information System (INIS)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed

  16. The "Lethal Chamber": Further Evidence of the Euthanasia Option.

    Science.gov (United States)

    Elks, Martin A.

    1993-01-01

    Historical discussions of the euthanasia or "lethal chamber" option in relation to people with mental retardation are presented. The paper concludes that eugenic beliefs in the primacy of heredity over environment and the positive role of natural selection may have condoned the poor conditions characteristic of large, segregated institutions and…

  17. Papaya Lethal Yellowing Virus (PLYV) Infects Vasconcellea cauliflora

    NARCIS (Netherlands)

    Amaral, P.P.R.; Resende, de R.O.; Souza, M.T.

    2006-01-01

    Papaya lethal yellowing virus (PLYV) é um dos três vírus descritos infectando mamoeiros (Carica papaya L.) no Brasil. Vasconcellea cauliflora (Jacq.) A. DC., antes denominada de Carica cauliflora (Jacq.), é uma reconhecida fonte de resistência natural ao Papaya ringspot virus (PRSV), causador da

  18. Dominant-lethal mutations and heritable translocations in mice

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed.

  19. Fighting Lethal Yellowing Disease for Coconut Farmers (CIFSRF ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Copra is the dried kernel of the coconut, which is used to extract coconut oil. Coconut is the main income source for the coastal region's poor farmers. Over the past 10 years, Côte d'Ivoire lethal yellowing disease has destroyed more than 350 hectares of coconut and caused losses of 12,000 tons of copra per year.

  20. Why the United States Must Adopt Lethal Autonomous Weapon Systems

    Science.gov (United States)

    2017-05-25

    intelligence , Lethal Autonomous Weapon Systems, energy production, energy storage, three-dimensional printing , bandwidth improvements, computer...views on the morality of artificial intelligence (AI) and robotics technology. Eastern culture sees artificial intelligence as an economic savior...capable of improving their society. In contrast, Western culture regards artificial intelligence with paranoia, anxiety, and skepticism. As Eastern

  1. Evolution of the dose values and image quality for the X-ray of thorax postero/anterior in mature patients of the service of imagenology of the Hospital Dr. Juan Noe of Arica

    International Nuclear Information System (INIS)

    Ubeda, Carlos; Galaz, Sergio; Leyton, Fernando; Delgado, Otto; Espinosa, Alfonso; Inzulza, Alonso; Ramirez, Raul; Blanco, Daniel; Oyarzun, Carlos

    2008-01-01

    Full text: International Atomic Energy Agency defined guidance level for medical exposure, for the exams of general radiology, reason why the objective of the present work was to evaluate the evolution of the doses for the radiological exam of thorax posterior/anterior among the years 2005 at 2007. The used design was of traverse, descriptive, analytic and comparative type. The study population corresponded to 2 groups of 50 patients selected at random, of both sexes that attended the imagenology service of the public hospital Dr. Juan Noe Crevanni of the city of Arica, to be carried out a X-ray of thorax posterior/anterior. The first group of patients corresponded the participants in the project ARCAL LXXV (Determination of guidance level for Conventional Radiology and Interventionist) carried out in the year 2005. The second group of patients was those incorporate ones during the year 2007 to the project RLA/9/057 (Radiological Protection of Patient in Medical Exhibitions). Both investigations were sponsored by the International Atomic Energy Agency, The Institute of Health Publishes and the Chilean Commission of Nuclear Energy. The stages of the study were divided in: characterization of the yield of the teams, taking of exams, evaluation image quality, estimate of the dose values and statistical analysis. The mean values from entrance surface air kerma for the radiological exam of thorax posterior/anterior vary of 0,14 mGy (S.D. 0.29) to 0.08 mGy (S.D. 0.31), among the years 2005 and 2007 respectively, being this significant difference (p=0.001). Both values are inferior to the value recommended in the Adenda III of the BSS. As for the proportions of execution of the approaches of image quality this it was of 0.95 for the project ARCAL LXXV and 0.92 for the project RLA/9/057, without being this significant difference. The continuous evaluation of the guidance level for medical exposure, associated to the quality of the images constitutes an estimator on the

  2. Bipyridine (2,2′-dipyridyl) potentiates Escherichia coli lethality induced by nitrogen mustard mechlorethamine

    International Nuclear Information System (INIS)

    De Alencar, T.A.M.; Wilmart-Gonçalves, T.C.; Vidal, L.S.; Fortunato, R.S.; Leitão, A.C.; Lage, C.

    2014-01-01

    Highlights: • Reduction of Fe 2+ ensues a respiratory burst to reduce the oxidized iron pool. • Through Harber–Weiss recycling, superoxide electrons can reduce oxidized iron. • Redox imbalance sensitized repair proficient Escherichia coli to mustard lethal crosslinks. • A stronger synergism impacted survival of a superoxide dismutase-deficient strain. • Anti-cancer cocktails added of an iron chelator may impact hypoxia and genotoxicity. - Abstract: Alkylating agents are used in anti-tumor chemotherapy because they bind covalently to DNA and generate adducts that may lead to cell death. Bifunctional (HN2) and monofunctional (HN1) nitrogen are two such agents, and HN2 was the first drug successfully employed in anti-leukemia chemotherapy. Currently, HN2 is used either alone or combined with other drugs to treat Hodgkin's disease. It is well known that several crosslinking agents require metabolic activation via reactive oxygen species (ROS) to exert their lethal effects. The objective of this work was therefore to determine whether the abovementioned mustards would also require metabolic activation to exert lethal action against Escherichia coli. For this purpose, we measured survival following exposure to HN2 in E. coli strains that were deficient in nucleotide excision repair (uvrA NER mutant), base excision repair (xthA nfo nth fpg BER mutant) or superoxide dismutase (sodAB mutant) activity. We also performed the same experiments in cells pretreated with an iron chelator (2,2′-dipyridyl, DIP). The NER and BER mutants were only sensitive to HN2 treatment (survival rates similar to those of the wild-type were achieved with 5-fold lower HN2 doses). However, wild-type and sodAB strains were not sensitive to treatment with HN2. In all tested strains, survival dropped by 2.5-fold following pretreatment with DIP compared to treatment with HN2 alone. Furthermore, DIP treatment increased ROS generation in both wild type and sodAB-deficient strains. Based

  3. Bipyridine (2,2′-dipyridyl) potentiates Escherichia coli lethality induced by nitrogen mustard mechlorethamine

    Energy Technology Data Exchange (ETDEWEB)

    De Alencar, T.A.M.; Wilmart-Gonçalves, T.C.; Vidal, L.S.; Fortunato, R.S.; Leitão, A.C. [Laboratório de Radiobiologia Molecular (Brazil); Lage, C., E-mail: claudia_lage_dna@yahoo.com.br [Laboratório de Radiações em Biologia (Brazil)

    2014-07-15

    Highlights: • Reduction of Fe{sup 2+} ensues a respiratory burst to reduce the oxidized iron pool. • Through Harber–Weiss recycling, superoxide electrons can reduce oxidized iron. • Redox imbalance sensitized repair proficient Escherichia coli to mustard lethal crosslinks. • A stronger synergism impacted survival of a superoxide dismutase-deficient strain. • Anti-cancer cocktails added of an iron chelator may impact hypoxia and genotoxicity. - Abstract: Alkylating agents are used in anti-tumor chemotherapy because they bind covalently to DNA and generate adducts that may lead to cell death. Bifunctional (HN2) and monofunctional (HN1) nitrogen are two such agents, and HN2 was the first drug successfully employed in anti-leukemia chemotherapy. Currently, HN2 is used either alone or combined with other drugs to treat Hodgkin's disease. It is well known that several crosslinking agents require metabolic activation via reactive oxygen species (ROS) to exert their lethal effects. The objective of this work was therefore to determine whether the abovementioned mustards would also require metabolic activation to exert lethal action against Escherichia coli. For this purpose, we measured survival following exposure to HN2 in E. coli strains that were deficient in nucleotide excision repair (uvrA NER mutant), base excision repair (xthA nfo nth fpg BER mutant) or superoxide dismutase (sodAB mutant) activity. We also performed the same experiments in cells pretreated with an iron chelator (2,2′-dipyridyl, DIP). The NER and BER mutants were only sensitive to HN2 treatment (survival rates similar to those of the wild-type were achieved with 5-fold lower HN2 doses). However, wild-type and sodAB strains were not sensitive to treatment with HN2. In all tested strains, survival dropped by 2.5-fold following pretreatment with DIP compared to treatment with HN2 alone. Furthermore, DIP treatment increased ROS generation in both wild type and sodAB-deficient strains

  4. Protective Effect of Phillyrin on Lethal LPS-Induced Neutrophil Inflammation in Zebrafish

    Directory of Open Access Journals (Sweden)

    Liling Yang

    2017-10-01

    Full Text Available Background/Aims: Forsythia suspensa Vahl. (Oleaceae fruits are widely used in traditional Chinese medicine to treat pneumonia, typhoid, dysentery, ulcers and oedema. Antibacterial and anti-inflammatory activities have been reported for phillyrin (PHN, the main ingredient in Forsythia suspensa Vahl fruits, in vitro. However, the underlying mechanisms in vivo remain poorly defined. In this study, we discovered that PHN exerted potent anti-inflammatory effects in lethal LPS-induced neutrophil inflammation by suppressing the MyD88-dependent signalling pathway in zebrafish. Methods: LPS-yolk microinjection was used to induce a lethal LPS-infected zebrafish model. The effect of PHN on the survival of zebrafish challenged with lethal LPS was evaluated using survival analysis. The effect of PHN on neutrophil inflammation grading in vivo was assessed by tracking neutrophils with a transgenic line. The effects of PHN on neutrophil production and migration were analysed by SB+ cell counts during consecutive hours after modelling. Additionally, key cytokines and members of the MyD88 signalling pathway that are involved in inflammatory response were detected using quantitative RT-PCR. To assess gene expression changes during consecutive hours after modelling, the IL-1β, IL-6, TNF-α, MyD88, TRIF, ERK1/2, JNK, IκBa and NF-κB expression levels were measured. Results: PHN could protect zebrafish against a lethal LPS challenge in a dose-dependent manner, as indicated by decreased neutrophil infltration, reduced tissue necrosis and increased survival rates. Up-regulated IL-1β, IL-6 and TNF-α expression also showed the same tendencies of depression by PHN. Critically, PHN significantly inhibited the LPS-induced activation of MyD88, IκBa, and NF-κB but did not affect the expression of ERK1/2 MAPKs or JNK MAPKs in LPS-stimulated zebrafish. Additionally, PHN regulated the MyD88/IκBα/NF-κB signalling pathway by controlling IκBα, IL-1β, IL-6, and TNF

  5. Annotating novel genes by integrating synthetic lethals and genomic information

    Directory of Open Access Journals (Sweden)

    Faty Mahamadou

    2008-01-01

    Full Text Available Abstract Background Large scale screening for synthetic lethality serves as a common tool in yeast genetics to systematically search for genes that play a role in specific biological processes. Often the amounts of data resulting from a single large scale screen far exceed the capacities of experimental characterization of every identified target. Thus, there is need for computational tools that select promising candidate genes in order to reduce the number of follow-up experiments to a manageable size. Results We analyze synthetic lethality data for arp1 and jnm1, two spindle migration genes, in order to identify novel members in this process. To this end, we use an unsupervised statistical method that integrates additional information from biological data sources, such as gene expression, phenotypic profiling, RNA degradation and sequence similarity. Different from existing methods that require large amounts of synthetic lethal data, our method merely relies on synthetic lethality information from two single screens. Using a Multivariate Gaussian Mixture Model, we determine the best subset of features that assign the target genes to two groups. The approach identifies a small group of genes as candidates involved in spindle migration. Experimental testing confirms the majority of our candidates and we present she1 (YBL031W as a novel gene involved in spindle migration. We applied the statistical methodology also to TOR2 signaling as another example. Conclusion We demonstrate the general use of Multivariate Gaussian Mixture Modeling for selecting candidate genes for experimental characterization from synthetic lethality data sets. For the given example, integration of different data sources contributes to the identification of genetic interaction partners of arp1 and jnm1 that play a role in the same biological process.

  6. The lethality test used for estimating the potency of antivenoms against Bothrops asper snake venom: pathophysiological mechanisms, prophylactic analgesia, and a surrogate in vitro assay.

    Science.gov (United States)

    Chacón, Francisco; Oviedo, Andrea; Escalante, Teresa; Solano, Gabriela; Rucavado, Alexandra; Gutiérrez, José María

    2015-01-01

    The potency of antivenoms is assessed by analyzing the neutralization of venom-induced lethality, and is expressed as the Median Effective Dose (ED50). The present study was designed to investigate the pathophysiological mechanisms responsible for lethality induced by the venom of Bothrops asper, in the experimental conditions used for the evaluation of the neutralizing potency of antivenoms. Mice injected with 4 LD50s of venom by the intraperitoneal route died within ∼25 min with drastic alterations in the abdominal organs, characterized by hemorrhage, increment in plasma extravasation, and hemoconcentration, thus leading to hypovolemia and cardiovascular collapse. Snake venom metalloproteinases (SVMPs) play a predominat role in lethality, as judged by partial inhibition by the chelating agent CaNa2EDTA. When venom was mixed with antivenom, there was a venom/antivenom ratio at which hemorrhage was significantly reduced, but mice died at later time intervals with evident hemoconcentration, indicating that other components in addition to SVMPs also contribute to plasma extravasation and lethality. Pretreatment with the analgesic tramadol did not affect the outcome of the neutralization test, thus suggesting that prophylactic (precautionary) analgesia can be introduced in this assay. Neutralization of lethality in mice correlated with neutralization of in vitro coagulant activity in human plasma. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Characteristics of repair following very low doses

    International Nuclear Information System (INIS)

    Braby, L.A.; Metting, N.F.; Nelson, J.M.

    1987-01-01

    The effects of ionizing radiation on living systems being with the physical processes of energy deposition and develop through many stages of chemical reaction and biological response. The modeling effort attempts to organize the available data and theories of all of these stages into self-consistent models that can be compared and tested. In some cases, important differences among models result in only small differences in cell survival within the ranges of dose and dose rate that are normally investigated. To overcome this limitation, new ways of irradiating cells at extremes of dose rate, or ways of evaluating the effects of very small doses, are developed. Mathematical modeling and cellular studies complement each other. It has recently been found that some mechanisms are not adequate to account for the interaction of dose and repair time as they affect the reproductive survival of plateau-phase Chinese hamster ovary (CHO) cells. Repair of radiation-induced cellular damage plays a central role in the survival of cells exposed to doses of 1 Gy or more. This repair is responsible for the dose rate, split-dose and delayed plating effect and can be evaluated. Because split-dose and dose-rate experiments involve repair during irradiation and delayed plating experiments involve repair after irradiation is completed, it was originally thought that different repair processes were involved. It is now clear that this is not necessarily the case. Appropriately designed models can account for observed effects at conventional doses (1 Gy or more) whether they assume all damage is lethal unless repaired or some damage is innocuous unless it interacts with additional damage. The fact that the survival following a plating delay is always less than the survival following immediate plating at low doses indicates that the damage produced is probably not potentially lethal

  8. Microbiological aspects relating to the choice of radiation sterilization dose

    International Nuclear Information System (INIS)

    Whitby, J.L.

    1993-01-01

    Ionizing radiation is widely used for sterilization of single-use medical devices, and it is employed for its lethal effect on microbial life. Microbes are capable of regenerating from a single surviving cell, and individual cells of some microbial species are highly resistant to the lethal effects of radiation. It is necessary to employ radiation doses far in excess of those lethal to man or animals to ensure that no viable microbe remains to repopulate the device or the patient at the time that the device is used. Ionizations induce the production of short-lived free radicals that also induce lethal changes in cells. The sensitivity of microbial species to these changes varies markedly but since the changes are induced within the cell, each cell has to sustain the necessary amount of lethal damage before death will occur. Therefore the death of cells will occur in the exponential mode the surviving fraction decreasing with increasing dose. Using a semi-logarithmic plot, curves of three types may be generated, a simple exponential curve with a constant slope over the whole dose range, one where an initial shoulder is followed by a constant slope, and curves which are concave, and only seen in mixed bacterial populations of differing radiation resistance. (author)

  9. Lethal Effect of Gamma Irradiation on the Potato Tuber Moth, Phthorimaea operculella (Zeller) and its Effect on Certain Physicochemical Properties of Potato Tubers

    International Nuclear Information System (INIS)

    Aly, G.M.; Rizk, S. A.; Abdalla, R.S.; Sobeiha, A.M.K.; Dahroug, S.M.

    2012-01-01

    Exposure of 4-day-old eggs of Phthorimaea operculella (Zeller) to a dose level of 800 Gy of gamma radiation caused complete mortality and prevent egg hatching after 4 days from exposure to radiation. This dose level was considered as the lethal dose for the egg stage. The dose levels of 700 and 2800 Gy were considered lethal for the full grown larvae after periods of 9 and 1 days elapsed respectively from exposure to gamma radiation .The percent larval mortality increased with the increase of both the dose level applied and the time elapsed after exposure to gamma radiation. Irradiation of full grown pupae at the dose level 1900 Gy resulted in a complete reduction of adult emergence, reached 100 % . It could be concluded that gamma irradiation with a dose level 2800 Gy caused complete mortality to different stages of Phthorimaea operculella. Moreover, the physical and chemical properties of irradiated potato tubers did not significantly differ as compared to unirradiated tubers .This obtained, fatal irradiation dose did not exceed the safe limits recommended by the international organization FAO/WHO.

  10. Radiation-induced mutagenicity and lethality in tryptophan-requiring auxotrophs of escherichia coli

    International Nuclear Information System (INIS)

    Xu Rong; Qian Hongwei; Yao Fenying; Gu Shuzhu; Xu Jiaxin; Bi Hekan; Liu Yuying

    1989-01-01

    Mutation and killing caused by X-ray radiation and 60 Co γ-ray radiation were studied in three different tryptophan-requiring auxotrophs (WP2, Wp2A, Cm 891) of Escherichia coli. These testers are sensitive to base pair substitution mutagens. Cm891 carries a R-factor and is more sensitive than WP2 and WP2A to radiation-induced mutation and lethality. The results of the study show that (1) ionizing radiation was mutagenic to E. coli, (2) the order of mutagenic sensitivity among three strains to ionizing radiation was Cm891 > WP2A > WP2, (3) the dose rate of γ-ray influences mutagenicity and lethalty of E. coli strain, (4) the toxicity and mutagenicity of γ-ray were similar to X-ray when Cm891 was tested, however, γ-ray was more toxic and mutagenic than X-ray to WP2A ang WP2

  11. Reduction of radio-contamination of vines by the method of 'non-lethal defoliation'

    International Nuclear Information System (INIS)

    Arapis, G.

    1998-01-01

    This study is included in the European Commission Programme RESSAC (Rehabilitation of Soils and Surfaces after a nuclear Accident). Its objective is to investigate the possibility of using 'non-lethal defoliation' as a countermeasure to mitigate the foliar uptake of radionuclides by plant leaves. We experimented on vines in productive agricultural fields in Spata - Attica, Greece. Interception factors and translocation of radionuclides studies were performed by using 134 Cs as marker. The deposition of 134 Cs was dry. Two pesticides, Harvade 60% FL and Basta 20 S.L., were used as defoliants. Our data showed that the recommended commercial doses of these chemicals resulted in defoliating up to 80% of the plants. We observed a reduction of radioactivity translocation to grapes by half, related to the defoliating degree. The efficacy of Harvade seemed higher than that of Basta. (authors)

  12. Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats

    Directory of Open Access Journals (Sweden)

    S. Sipka

    1997-01-01

    Full Text Available Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats. Wistar male rats were sensitized to endotoxin by Pb acetate. The survival of rats were compared in groups of animals endotoxin shock treated and non-treated with insoluble glycogen. Furthermore, we have determined in vitro the binding capacity of insoluble glycogen for endotoxin, tumour necrosis factor alpha, interleukin-1 and secretable phospholipase A2. Use of 10 mg/kg dose of insoluble glycogen could completely prevent the lethality of shock induced by LD50 quantity of endotoxin in rats. All animals treated survived. Insoluble glycogen is a form of ‘metabolizable internal adsorbents’. It can potentially be used for treatment of septic shock.

  13. "Rickettsia amblyommii" induces cross protection against lethal Rocky Mountain spotted fever in a guinea pig model.

    Science.gov (United States)

    Blanton, Lucas S; Mendell, Nicole L; Walker, David H; Bouyer, Donald H

    2014-08-01

    Rocky Mountain spotted fever (RMSF) is a severe illness caused by Rickettsia rickettsii for which there is no available vaccine. We hypothesize that exposure to the highly prevalent, relatively nonpathogenic "Rickettsia amblyommii" protects against R. rickettsii challenge. To test this hypothesis, guinea pigs were inoculated with "R. amblyommii." After inoculation, the animals showed no signs of illness. When later challenged with lethal doses of R. rickettsii, those previously exposed to "R. amblyommii" remained well, whereas unimmunized controls developed severe illness and died. We conclude that "R. amblyommii" induces an immune response that protects from illness and death in the guinea pig model of RMSF. These results provide a basis for exploring the use of low-virulence rickettsiae as a platform to develop live attenuated vaccine candidates to prevent severe rickettsioses.

  14. Evaluation of the performance of three elastomers for non-lethal projectile applications

    Science.gov (United States)

    Thota, N.; Epaarachchi, J.; Lau, K. T.

    2015-09-01

    Less lethal kinetic ammunitions with soft noses such as eXact iMpact 1006, National Sports Spartan and B&T have been commonly used by military and law enforcement officers in the situations where lethal force is not warranted. In order to explore new materials to be used as nose in such ammunitions, a scholastic study using finite element simulations has been carried out to evaluate the effectiveness of two rubber like elastomers and a polyolefinic foam (low density, highly compressible, stiff and closed cell type of thermos plastic elastomer). State-of-the art thorax surrogate MTHOTA has been employed for the evaluation of blunt thoracic trauma. Force-rigid wall method was employed for the evaluation of head damage curves for each material. XM 1006 has been used as the benchmark projectile for the purpose of comparison. Both blunt thoracic trauma and head damage criterion point of view, both rubbers (R1 and R2) have yielded high values of VCmax and peak impact force. Polyolefinic foam (F1) considered in the study has yielded very promising VCmax values and very less peak impact force when compared with those of bench mark projectile XM 1006.

  15. Low doses effects of ionizing radiation on Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Durand, J.; Broock, M. van; Gillette, V.H.

    2000-01-01

    The exposure of living cells to low doses of ionizing radiation induce in response the activation of cellular protection mechanisms against subsequent larger doses of radiation. This cellular adaptive response may vary depending on radiation intensity and time of exposure, and also on the testing probes used whether they were mammalian cells, yeast, bacteria and other organisms or cell types. The mechanisms involved are the genome activation, followed by DNA repair enzymes synthesis. Due to the prompt cell response, the cell cycle can be delayed, and the secondary detoxification of free radicals and/or activation of membrane bound receptors may proceed. All these phenomena are submitted to intense scientific research nowadays, and their elucidation will depend on the complexity of the organism under study. In the present work, the effects of low doses of ionizing radiation (gamma rays) over a suspension of the yeast Saccharomyces cerevisiae (Baker's yeast) was studied, mainly in respect to survival rate and radio-adaptive response. At first, the yeast surviving curve was assessed towards increasing doses, and an estimation of Lethal Dose 50 (LD50) was made. The irradiation tests were performed at LINAC (electrons Linear Accelerator) where electron energy reached approximately 2.65 MeV, and gamma-radiation was produced for bremsstrahlung process over an aluminium screen target. A series of experiments of conditioning doses was performed and an increment surviving fraction was observed when the dose was 2.3 Gy and a interval time between this and a higher dose (challenging dose) of 27 Gy was 90 minutes. A value of 58 ± 4 Gy was estimated for LD50, at a dose rate of 0.44 ± 0.03 Gy/min These quantities must be optimized. Besides data obtained over yeast survival, an unusual increasing amount of tiny yeast colonies appeared on the agar plates after incubation, and this number increased as increasing the time exposure. Preliminary results indicate these colonies as

  16. Low dose out-of-field radiotherapy, part 2: Calculating the mean photon energy values for the out-of-field photon energy spectrum from scattered radiation using Monte Carlo methods.

    Science.gov (United States)

    Skrobala, A; Adamczyk, S; Kruszyna-Mochalska, M; Skórska, M; Konefał, A; Suchorska, W; Zaleska, K; Kowalik, A; Jackowiak, W; Malicki, J

    2017-08-01

    During radiotherapy, leakage from the machine head and collimator expose patients to out-of-field irradiation doses, which may cause secondary cancers. To quantify the risks of secondary cancers due to out-of-field doses, it is first necessary to measure these doses. Since most dosimeters are energy-dependent, it is essential to first determine the type of photon energy spectrum in the out-of-field area. The aim of this study was to determine the mean photon energy values for the out-of-field photon energy spectrum for a 6 MV photon beam using the GEANT 4-Monte Carlo method. A specially-designed large water phantom was simulated with a static field at gantry 0°. The source-to-surface distance was 92cm for an open field size of 10×10cm2. The photon energy spectra were calculated at five unique positions (at depths of 0.5, 1.6, 4, 6, 8, and 10cm) along the central beam axis and at six different off-axis distances. Monte Carlo simulations showed that mean radiation energy levels drop rapidly beyond the edge of the 6 MV photon beam field: at a distance of 10cm, the mean energy level is close to 0.3MeV versus 1.5MeV at the central beam axis. In some cases, the energy level actually increased even as the distance from the field edge increased: at a depth of 1.6cm and 15cm off-axis, the mean energy level was 0.205MeV versus 0.252MeV at 20cm off-axis. The out-of-field energy spectra and dose distribution data obtained in this study with Monte Carlo methods can be used to calibrate dosimeters to measure out-of-field radiation from 6MV photons. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  17. Metabolic changes after non-lethal X-irradiation of rats. I

    International Nuclear Information System (INIS)

    Ahlersova, E.; Ahlers, I.; Slavkovska, E.; Praslicka, M.

    1981-01-01

    Male rats of the Wistar strain were fasted overnight prior to exposure to single whole-body X-ray dose of 2.39 Gy (250 R). Irradiated and sham-irradiated rats were pair-fed for 5 days, in the following period they were fed ad libitum. The levels of corticosterone and immunoreactive insulin in serum, glucose in blood, glycogen in liver, heart and skeletal muscle were determined 1 and 6 h, 1, 2, 3, 7, 14, 21, 28, and 38 days after irradiation and sham-irradiation. Irradiation of rats resulted, in one hour, in a decrease and, in two days, in an increase in blood glucose level. A marked increase in liver glycogen persisted from 6 h to 21 days after irradiation. The level of glycogen in the skeletal muscle was reduced after 6 h and increased on days 3 and 14. Heart muscle glycogen declined within the first 24 h and rose at 14 days after exposure. The kinetics of changes in the heart and skeletal muscle glycogen following non-lethal irradiation was similar and indicated an overlap of changes produced by fasting with those brought about by irradiation, particularly during the first week. Corticosterone in serum was markedly increased in rats 24 and 72 h after irradiation compared to pair-fed controls. The serum insulin concentration did not change after irradiation, except for a single increase on day 21. Irradiation with non-lethal doses produced changes in the parameters of the carbohydrate metabolism studied, except for serum insulin which reflected the changes in the nutrition regimen upon pair-feeding rather than the effect of ionizing irradiation. (author)

  18. The {sup 68}Ga/{sup 177}Lu theragnostic concept in PSMA targeting of castration-resistant prostate cancer: correlation of SUV{sub max} values and absorbed dose estimates

    Energy Technology Data Exchange (ETDEWEB)

    Scarpa, Lorenza; Buxbaum, Sabine; Kendler, Dorota; Decristoforo, Clemens; Uprimny, Christian; Virgolini, Irene [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Fink, Katharina [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Medical University of Innsbruck, Department of Radiotherapy / Radiation Oncology, Innsbruck (Austria); Bektic, Jasmin; Horninger, Wolfgang [Medical University of Innsbruck, Department of Urology, Innsbruck (Austria); Gruber, Leonhard [Medical University of Innsbruck, Department of Radiology, Innsbruck (Austria); Lukas, Peter [Medical University of Innsbruck, Department of Radiotherapy / Radiation Oncology, Innsbruck (Austria)

    2017-05-15

    A targeted theragnostic approach based on increased expression of prostate-specific membrane antigen (PSMA) on PC cells is an attractive treatment option for patients with metastatic castration-resistant prostate cancer (mCRPC). Ten consecutive mCRPC patients were selected for {sup 177}Lu-PSMA617 therapy on the basis of PSMA-targeted {sup 68}Ga-PSMA-HBED-CC PET/CT diagnosis showing extensive and progressive tumour load. Following dosimetry along with the first therapy cycle restaging ({sup 68}Ga-PSMA-HBED-CC and {sup 18}F-NaF PET/CT) was performed after 2 and 3 therapy cycles (each 6.1 ± 0.3 GBq, range 5.4-6.5 GBq) given intravenously over 30 minutes, 9 ± 1 weeks apart. PET/CT scans were compared to {sup 177}Lu-PSMA617 24-hour whole-body scans and contrast-enhanced dual-phase CT. Detailed comparison of SUVmax values and absorbed tumour doses was performed. {sup 177}Lu-PSMA617 dosimetry indicated high tumour doses for skeletal (3.4 ± 1.9 Gy/GBq; range 1.1-7.2 Gy/GBq), lymph node (2.6 ± 0.4 Gy/GBq; range 2.3-2.9 Gy/GBq) as well as liver (2.4 ± 0.8 Gy/GBq; range 1.7-3.3 Gy/GBq) metastases whereas the dose for tissues/organs was acceptable in all patients for an intention-to-treat activity of 18 ± 0.3 GBq. Three patients showed partial remission, three mixed response, one stable and three progressive disease. Decreased {sup 177}Lu-PSMA617 and {sup 68}Ga-PSMA-HBED-CC uptake (mean SUVmax values 20.2 before and 15.0 after 2 cycles and 11.5 after 3 cycles, p < 0.05) was found in 41/54 skeletal lesions, 12/13 lymph node metastases, 3/5 visceral metastases and 4/4 primary PC lesions. Due to substantial individual variance, dosimetry is mandatory for a patient-specific approach following {sup 177}Lu-PSMA617 therapy. Higher activities and/or shorter treatment intervals should be applied in a larger prospective study. (orig.)

  19. Repair of potentially lethal radiation damage: comparison of neutron and x-ray RBE and implications for radiation therapy

    International Nuclear Information System (INIS)

    Hall, E.J.; Kraljevic, U.

    1976-01-01

    Experiments with Chinese hamster cells have shown that neutron irradiation does not result in repair of potentially lethal damage (PLD), i.e., that which can be influenced by changes in environmental conditions following irradiation. Since PLD is presumed to be repaired in tumors but not in normal tissues, this absence of differential sparing of tumor cells relative to normal tissues--a feature characteristic of irradiation with x rays--represents an advantage of neutrons in addition to their reduced oxygen effect. At a given dose, the difference in relative biological effectiveness (RBE) between tumors and normal tissues corresponds to a 5 percent increase in tumor dose with no concomitant increase in dose to normal tissues, which could be significant in cancer therapy

  20. Valuing Essays: Essaying Values

    Science.gov (United States)

    Badley, Graham

    2010-01-01

    The essay regularly comes under attack. It is criticised for being rigidly linear rather than flexible and reflective. I first challenge this view by examining reasons why the essay should be valued as an important genre. Secondly, I propose that in using the essay form students and academics necessarily exemplify their own critical values. Essays…

  1. A quick method for testing recessive lethal damage with a diploid strain of Aspergillus nidulans

    International Nuclear Information System (INIS)

    Morpurgo, G.; Puppo, S.; Gualandi, G.; Conti, L.

    1978-01-01

    A simple method capable of detecting recessive lethal damage in a diploid strain of Aspergillus nidulans is described. The method scores the recessive lethals on the 1st, the 3rd and the 5th chromosomes, which represent about 40% of the total map of A. nidulans. Two examples of induced lethals, with ultraviolet irradiation and methyl methanesulfonate are shown. The frequency of lethals may reach 36% of the total population with UV irradiation. (Auth.)

  2. Humanitarian Algorithms : A Codified Key Safety Switch Protocol for Lethal Autonomy

    OpenAIRE

    Nyagudi, Nyagudi Musandu

    2014-01-01

    With the deployment of lethal autonomous weapons, there is the requirement that any such platform complies with the precepts of International Humanitarian Law. Humanitarian Algorithms[9: p. 9] ensure that lethal autonomous weapon systems perform military/security operations, within the confines of International Humanitarian Law. Unlike other existing techniques of regulating lethal autonomy this scheme advocates for an approach that enables Machine Learning. Lethal autonomous weapons must be ...

  3. The effect of sub-lethal damage repair and exchange on the final slope of cell survival curves

    International Nuclear Information System (INIS)

    Carlone, M.C.; Wilkins, D.E.; Raaphorst, G.P.

    2003-01-01

    Full text: The Lea-Catcheside dose rate protraction factor, G, is the most widely used model to describe the effects of dose rate on cell survival. In the linear quadratic formalism, this factor modifies the beta component of cell killing; G is greatest for acute irradiations while vanishing at low dose rates. We have found a simple compartmental model that can derive the Lea-Catcheside function. This compartmental model clearly shows that the G function can only be derived using a little known assumption: the diminution of sub-lethal damage due to exchange of repairable lesions is negligible compared to that due to repair. This assumption was explicitly stated by Lea, but it does not appear to have been restated or verified since very early work on cell survival. The implication of this assumption is that sub-lethal damage can be modeled without considering exchange, which is evidenced by the fact that the G function does not contain parameters relating to exchange. By using a new model that fully accounts for repair and exchange of sublethal lesions, a cell survival expression that has a modified G function, but that retains the linear quadratic formalism, can be obtained. At low doses, this new model predicts linear-quadratic behavior, but the behavior gradually changes to mono-exponential at high doses, which is consistent with experimental observations. Modeling cell survival of well-known survival curves using the modified linear quadratic model shows statistically significant improvement in the fits to the cell survival data as compared to best fits obtained with the linear quadratic model. It is shown that these improvements in fits are due to a superior representation of the high dose region of the survival curve

  4. Leaf gas exchange performance and the lethal water potential of five European species during drought.

    Science.gov (United States)

    Li, Shan; Feifel, Marion; Karimi, Zohreh; Schuldt, Bernhard; Choat, Brendan; Jansen, Steven

    2016-02-01

    Establishing physiological thresholds to drought-induced mortality in a range of plant species is crucial in understanding how plants respond to severe drought. Here, five common European tree species were selected (Acer campestre L., Acer pseudoplatanus L., Carpinus betulus L., Corylus avellana L. and Fraxinus excelsior L.) to study their hydraulic thresholds to mortality. Photosynthetic parameters during desiccation and the recovery of leaf gas exchange after rewatering were measured. Stem vulnerability curves and leaf pressure-volume curves were investigated to understand the hydraulic coordination of stem and leaf tissue traits. Stem and root samples from well-watered and severely drought-stressed plants of two species were observed using transmission electron microscopy to visualize mortality of cambial cells. The lethal water potential (ψlethal) correlated with stem P99 (i.e., the xylem water potential at 99% loss of hydraulic conductivity, PLC). However, several plants that were stressed beyond the water potential at 100% PLC showed complete recovery during the next spring, which suggests that the ψlethal values were underestimated. Moreover, we observed a 1 : 1 relationship between the xylem water potential at the onset of embolism and stomatal closure, confirming hydraulic coordination between leaf and stem tissues. Finally, ultrastructural changes in the cytoplasm of cambium tissue and mortality of cambial cells are proposed to provide an alternative approach to investigate the point of no return associated with plant death. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Diabetes susceptibility of BALB/cBOM mice treated with streptozotocin. Inhibition by lethal irradiation and restoration by splenic lymphocytes

    International Nuclear Information System (INIS)

    Paik, S.G.; Blue, M.L.; Fleischer, N.; Shin, S.

    1982-01-01

    In genetically susceptible strains of mice, repeated injections of a subdiabetogenic dose of streptozotocin induces the development of progressive insulin-dependent hyperglycemia. We showed previously that host T-cell functions play an obligatory etiologic role in this experimental disease by demonstrating that the athymic nude mouse is resistant to diabetes induction unless its T-cell functions are reconstituted by thymus graft. Here we show that lethal irradiation of euthymic (+/nu) mice of BALB/cBOM background causes selective resistance of the mice to the diabetogenic effects of the multiple low doses of streptozotocin without affecting their sensitivity to a high pharmacologic dose of the toxin. We also show that reconstitution of the irradiated mice with splenic lymphocytes causes the restoration of diabetes susceptibility. Lethally irradiated mice thus represent a useful experimental model for analyzing the host functions involved in the development of this disease. These results provide an additional support for the hypothesis that the induction of diabetes in this model system is mediated by an autoimmune amplification mechanism

  6. Bacillus anthracis lethal toxin disrupts TCR signaling in CD1d-restricted NKT cells leading to functional anergy.

    Directory of Open Access Journals (Sweden)

    Sunil K Joshi

    2009-09-01

    Full Text Available Exogenous CD1d-binding glycolipid (alpha-Galactosylceramide, alpha-GC stimulates TCR signaling and activation of type-1 natural killer-like T (NKT cells. Activated NKT cells play a central role in the regulation of adaptive and protective immune responses against pathogens and tumors. In the present study, we tested the effect of Bacillus anthracis lethal toxin (LT on NKT cells both in vivo and in vitro. LT is a binary toxin known to suppress host immune responses during anthrax disease and intoxicates cells by protective antigen (PA-mediated intracellular delivery of lethal factor (LF, a potent metalloprotease. We observed that NKT cells expressed anthrax toxin receptors (CMG-2 and TEM-8 and bound more PA than other immune cell types. A sub-lethal dose of LT administered in vivo in C57BL/6 mice decreased expression of the activation receptor NKG2D by NKT cells but not by NK cells. The in vivo administration of LT led to decreased TCR-induced cytokine secretion but did not affect TCR expression. Further analysis revealed LT-dependent inhibition of TCR-stimulated MAP kinase signaling in NKT cells attributable to LT cleavage of the MAP kinase kinase MEK-2. We propose that Bacillus anthracis-derived LT causes a novel form of functional anergy in NKT cells and therefore has potential for contributing to immune evasion by the pathogen.

  7. The involvement of IL-17A in the murine response to sub-lethal inhalational infection with Francisella tularensis.

    Directory of Open Access Journals (Sweden)

    Gal Markel

    2010-06-01

    Full Text Available Francisella tularensis is an intercellular bacterium often causing fatal disease when inhaled. Previous reports have underlined the role of cell-mediated immunity and IFNgamma in the host response to Francisella tularensis infection.Here we provide evidence for the involvement of IL-17A in host defense to inhalational tularemia, using a mouse model of intranasal infection with the Live Vaccine Strain (LVS. We demonstrate the kinetics of IL-17A production in lavage fluids of infected lungs and identify the IL-17A-producing lymphocytes as pulmonary gammadelta and Th17 cells. The peak of IL-17A production appears early during sub-lethal infection, it precedes the peak of immune activation and the nadir of the disease, and then subsides subsequently. Exogenous airway administration of IL-17A or of IL-23 had a limited yet consistent effect of delaying the onset of death from a lethal dose of LVS, implying that IL-17A may be involved in restraining the infection. The protective role for IL-17A was directly demonstrated by in vivo neutralization of IL-17A. Administration of anti IL-17A antibodies concomitantly to a sub-lethal airway infection with 0.1xLD(50 resulted in a fatal disease.In summary, these data characterize the involvement and underline the protective key role of the IL-17A axis in the lungs from inhalational tularemia.

  8. Standardization of anti-lethal toxin potency test of antivenoms prepared from two different Agkistrodon halys venoms

    Directory of Open Access Journals (Sweden)

    K. H. Lee

    2006-01-01

    Full Text Available In Korea, antivenoms for the treatment of patients bitten by venomous snakes have been imported from Japan or China. Although there is cross-reactivity between these antibodies and venoms from snakes indigenous to Korea (e.g. Agkistrodon genus, protection is not optimal. Antivenoms specifically prepared to neutralize Korean snake venoms could be more effective, with fewer side effects. To this end, we established an infrastructure to develop national standards and created a standardized method to evaluate the efficacy of two horse-derived antivenoms using mouse lethal toxin test. Additionally, we determined the antivenoms neutralizing activity against lethal doses (LD50 of Agkistrodon halys (from Japan and Jiangzhe Agkistrodon halys (from China venoms. We also performed cross-neutralization tests using probit analysis on each pairing of venom and antivenom in order to check the possibility of using Jiangzhe A. halys venom as a substitute for A. halys venom, the current standard. Slope of A. halys venom with A. halys antivenom was 10.2 and that of A. halys venom with Jiangzhe A. halys antivenom was 9.6. However, Slope of Jiangzhe A. halys venom with A. halys antivenom was 4.7 while that of Jiangzhe A. halys venom with Jiangzhe A. halys antivenom was 11.5. Therefore, the significant difference in slope patterns suggests that Jiangzhe A. halys venom cannot be used as a substitute for the standard venom to test the anti-lethal toxin activity of antivenoms (p<0.05.

  9. Pacman dysplasia: a lethal skeletal dysplasia with variable radiographic features

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.F. [Dept. of Radiology, Children' s Hospital of the King' s Daughters, Norfolk (United States); Proud, V.K. [Dept. of Genetics, Children' s Hospital of the King' s Daughters, Norfolk (United States); Werner, A.L. [Dept. of Pathology, Children' s Hospital of the King' s Daughters, Norfolk (United States); Field, F.M.; Wilcox, W.F.; Lachman, R.S.; Rimoin, D.L. [International Skeletal Dysplasia Registry, Cedars-Sinai Medical Center, Los Angeles (United States)

    2003-04-01

    Background: Punctate or stippled cartilaginous calcifications are associated with many conditions, including chromosomal, infectious, endocrine, and teratogenic etiologies. Some of these conditions are clinically mild, while others are lethal. Accurate diagnosis can prove instrumental in clinical management and in genetic counseling. Objective: To describe the diagnostic radiographic features seen in Pacman dysplasia, a distinct autosomal recessive, lethal skeletal dysplasia. Materials and methods: We present the fourth reported case of Pacman dysplasia and compare the findings seen in our patient with the three previously described patients. Results: Invariable and variable radiographic findings were seen in all four cases of histologically proven Pacman dysplasia. Conclusion: Pacman dysplasia presents both constant and variable diagnostic radiographic features. (orig.)

  10. Neonatal lethal dwarfism with distinct skeletal malformations - a separate entity?

    Energy Technology Data Exchange (ETDEWEB)

    Rosendahl, K.; Maurseth, K.; Olsen, Oe.E. [Dept. of Paediatric Radiology, Haukeland University Hospital, Bergen (Norway); Halvorsen, O.J. [Dept. of Pathology, Haukeland University Hospital, Bergen (Norway); Gjelland, K. [Dept. of Gynaecology, Haukeland University Hospital, Bergen (Norway); Engebretsen, L. [Dept. of Genetics, Haukeland University Hospital, Bergen (Norway)

    2001-09-01

    We describe a case of neonatal lethal dwarfism characterised by short trunk, short, stick-like tubular bones, deficient ossification of the axial skeleton and broad, sclerotic horizontal ribs. Two similar cases have previously been reported as examples of the Neu-Laxova syndrome. However, the radiological findings of the Neu-Laxova syndrome, as reported in 16 out of 40 documented cases, show a heterogeneous pattern of minor features, which differ distinctively from those found in the previous two cases and by us. A literature research did not reveal similar cases, and we therefore suggest that our case, together with the two previous cases, may represent a new distinctive form of neonatal lethal dwarfism. (orig.)

  11. Neonatal lethal dwarfism with distinct skeletal malformations - a separate entity?

    International Nuclear Information System (INIS)

    Rosendahl, K.; Maurseth, K.; Olsen, Oe.E.; Halvorsen, O.J.; Gjelland, K.; Engebretsen, L.

    2001-01-01

    We describe a case of neonatal lethal dwarfism characterised by short trunk, short, stick-like tubular bones, deficient ossification of the axial skeleton and broad, sclerotic horizontal ribs. Two similar cases have previously been reported as examples of the Neu-Laxova syndrome. However, the radiological findings of the Neu-Laxova syndrome, as reported in 16 out of 40 documented cases, show a heterogeneous pattern of minor features, which differ distinctively from those found in the previous two cases and by us. A literature research did not reveal similar cases, and we therefore suggest that our case, together with the two previous cases, may represent a new distinctive form of neonatal lethal dwarfism. (orig.)

  12. Chemical and radiation induced late dominant lethal effects in mice

    International Nuclear Information System (INIS)

    Favor, J.; Crenshaw, J.W. Jr.; Soares, E.R.

    1978-01-01

    Although theoretically expected, experimental data to date have not shown dominant lethal expression to occur throughout the developmental period. Specifically, late post-implantation effects have not been demonstrated. The authors routinely use an experimental technique in which parental females mated to mutagenically treated males are allowed to give birth and wean their litter, and their uterine horns are then inspected for uterine scars indicative of live and dead embryos. In a number of experiments in which males were mutagenically treated with either chemicals or X-irradiation, a discrepancy was observed between the number of live embryos as determined by the scar technique and the number of live observed at birth, suggesting the possibility of embryonic losses at a late stage in development. Initial analyses showed that mutagenic treatment increased the percentage of these late losses. These differences were statistically significant in 2 of 3 analyses. Factors affecting statistical significance and an understanding of dominant lethal mutations are discussed. (Auth.)

  13. An improved brine shrimp larvae lethality microwell test method.

    Science.gov (United States)

    Zhang, Yi; Mu, Jun; Han, Jinyuan; Gu, Xiaojie

    2012-01-01

    This article described an improved brine shrimp larvae lethality microwell test method. A simply designed connecting vessel with alternative photoperiod was used to culture and collect high yield of active Artemia parthenogenetica nauplii for brine shrimp larvae lethality microwell test. Using this method, pure A. parthenogenetica nauplii suspension was easily cultured and harvested with high density about 100-150 larvae per milliliter and the natural mortality was reduced to near zero by elimination of unnecessary artificial disturbance. And its sensitivity was validated by determination of LC(50)-24 h of different reference toxicants including five antitumor agents, two pesticides, three organic pollutants, and four heavy metals salts, most of which exhibited LC(50)-24 h between 0.07 and 58.43 mg/L except for bleomycin and mitomycin C with LC(50)-24 h over 300 mg/L.

  14. Dominant lethals following administration of tritium (THO) to rat males

    International Nuclear Information System (INIS)

    Yagova, A.; Baev, I.; Bajrakova, A.

    1976-01-01

    Adult rat males were given a single intraperitoneal tritium (THO) injection at 0,01 or 0,001 mCi/g body weight (1/100 or 1/1000 of LDsub(50/30), respectively). Twelve days after treatment each male was mated to 3-5 intact females, and the latter were replaced by fresh ones every 12 following days over a 120-day period. Mated females were killed to score conceptions, corpora lutea, and live and dead embryos. Estimations were made of F 1 prenatal death rate (according to Bateman, 1958) and the frequency of induction of dominant lethal mutations (according to Roehrborn, 1970). The results observed indicated paternal exposure to tritium (THO) to produce dominant lethals both in pre- and post-meiotic germ cells in the rat. The extent of the genetic damage studied was found to depend on the amount of activity administered as well as on the time interval between treatment and conception. (author)

  15. The influence of continuous γ-irradiation at decreasing dose-rate on the survival rote and induction of gene mutations in cultured Chinese hamster cells

    International Nuclear Information System (INIS)

    Feoktistova, T.P.; Elisova, E.V.; Stavrakova, N.M.

    1991-01-01

    Continuous γ-irradiation at decreasing dose-rate was shown to be less effective than acute exposure with regard to the lethal effect and frequency of mutations of resistance to 6-thioguanine in cultured Chinese hamster cells. The cell population subjected to continuons irradiation was d more radioresistant than the intact one. Lethal and genetic effects of continuous irradiation at decreasing dose-rate were mainly determined by the contribution of the radiation dose received during the first 24 h of exposure

  16. Non-Lethal Weaponry: A Framework for Future Integration

    Science.gov (United States)

    1998-04-01

    community, but was widely popularized by John Naisbitt in his 1982 work, Megatrends . In short, it asserts that much may be learned about a dynamic, but...Notes 1 John Naisbitt, Megatrends : Ten New Directions Transforming Our Lives (New York, NY: Warner Books, Inc., 1982), 3-5. 2 Robert J. Bunker...lethals by opponents of biological and chemical weapons. The use of chemical agents…is seen as a Trojan Horse to circumvent the Chemical Weapons

  17. Genome Replikin Count Predicts Increased Infectivity/Lethality of Viruses

    OpenAIRE

    Samuel Bogoch; Elenore S. Bogoch

    2012-01-01

    The genomes of all groups of viruses whose sequences are listed on Pubmed, specimens since 1918, analyzed by a software from Bioradar UK Ltd., contain Replikins which range in concentration from a Replikin Count (number of Replikins per 100 amino acids) of less than 1 to 30 (see accompanying communications for higher Counts in tuberculosis, malaria, and cancer, associated with higher lethality). Counts of less than 4.0 were found in ‘resting’ virus states; Counts greater than 4....

  18. Spondyloepiphyseal dysplasia congenita. A cause of lethal neonatal dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Macpherson, R.I.; Wood, B.P.

    1980-07-01

    Spondyloepiphyseal dysplasia congenita is a form of primarily short trunk dwarfism, that is manifest at birth but generally has not been regarded as a cause of lethal neonatal dwarfism. Seven neonates with severe dwarfism are presented. The first survived the newborn period, but the other six were early neonatal deaths. All displayed the clinical and radiologic features of spondyloepiphyseal dysplasia congenita. The striking similarities between spondyloepiphyseal dysplasia congenita and achondrogenesis type 2 are discussed.

  19. Torrance type of lethal neonatal short-limbed platyspondylic dwarfism

    International Nuclear Information System (INIS)

    Kaibara, N.; Yokoyama, K.; Nakano, H.

    1983-01-01

    A rare case of lethal neonatal short-limbed platyspondylic dwarfism is described. Roentgenographic features of this case, distinctly different from those of the classical thanatophoric dysplasia, are indistinguishable from the other three types of short-limbed platyspondylic dwarfism. Histologic features of the cartilage in this case are not very different from those of the Torrance type, but the presence of focal disruption of column formation in this case suggests a wider spectrum for this entity. (orig.)

  20. Torrance type of lethal neonatal short-limbed platyspondylic dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Kaibara, N.; Yokoyama, K.; Nakano, H.

    1983-06-01

    A rare case of lethal neonatal short-limbed platyspondylic dwarfism is described. Roentgenographic features of this case, distinctly different from those of the classical thanatophoric dysplasia, are indistinguishable from the other three types of short-limbed platyspondylic dwarfism. Histologic features of the cartilage in this case are not very different from those of the Torrance type, but the presence of focal disruption of column formation in this case suggests a wider spectrum for this entity.

  1. First diagnosed lethal case of lyssavirus infection in Primorsky krai

    OpenAIRE

    Leonova, G.; Chentsova, I.; Petukhova, S.; Somova, L.; Belikov, S.; Kondratov, I.; Kryilova, N.; Plekhova, N.; Pavlenko, E.; Romanova, E.; Matsak, V.; Smirnov, G.; Novikov, D.

    2010-01-01

    The paper provides data of comprehensive study of lethal case of lyssavirus infection first diagnosed in Yakovlevsky municipal district in Primorsky Krai. The data of epidemiologic analysis (contact with a rattle mouse), clinical picture and results of virologic, morphological and molecular genetic tests allow attributing this case to lyssavirus infection. This is the first diagnosed case of lyssavirus infection in the Siberia and Far East.

  2. Transplantation of bone marrow cells into lethally irradiated mice

    International Nuclear Information System (INIS)

    Viktora, L.; Hermanova, E.

    1978-01-01

    Morphological changes were studied of megakaryocytes in the bone marrow and spleen of lethally irradiated mice (0.2 C/kg) after transplantation of living bone marrow cells. It was observed that functional trombopoietic megakaryocytes occur from day 15 after transplantation and that functional active megakaryocytes predominate in bone marrow and spleen from day 20. In addition, other types of cells, primarily granulocytes, were detected in some megakaryocytes. (author)

  3. Lethal mutagenesis: targeting the mutator phenotype in cancer.

    Science.gov (United States)

    Fox, Edward J; Loeb, Lawrence A

    2010-10-01

    The evolution of cancer and RNA viruses share many similarities. Both exploit high levels of genotypic diversity to enable extensive phenotypic plasticity and thereby facilitate rapid adaptation. In order to accumulate large numbers of mutations, we have proposed that cancers express a mutator phenotype. Similar to cancer cells, many viral populations, by replicating their genomes with low fidelity, carry a substantial mutational load. As high levels of mutation are potentially deleterious, the viral mutation frequency is thresholded at a level below which viral populations equilibrate in a traditional mutation-selection balance, and above which the population is no longer viable, i.e., the population undergoes an error catastrophe. Because their mutation frequencies are fine-tuned just below this error threshold, viral populations are susceptible to further increases in mutational load and, recently this phenomenon has been exploited therapeutically by a concept that has been termed lethal mutagenesis. Here we review the application of lethal mutagenesis to the treatment of HIV and discuss how lethal mutagenesis may represent a novel therapeutic approach for the treatment of solid cancers. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. The effect of a single lethal X-irradiation exposure on the activity of lipoprotein lipase in the tissues of the rat

    International Nuclear Information System (INIS)

    Sedlakova, A.; Ahlers, I.; Praslicka, M.

    1979-01-01

    Wistar male rats, both fed and fasting for 16 h prior to irradiation, were exposed to a single lethal X-ray dose of 387 mC/kg (1500R). The activity of lipoprotein lipase in white adipose (epididymal) tissue and heart muscle and the concentration of serum triglycerides were determined at 1, 6, 24, 48, and 72 h after irradiation. In the early time periods, at 1 and 6 h after exposure, the activity of lipoprotein lipase decreased in adipose tissue and increased in heart muscle of the irradiated fed rats; in fasting rats it decreased in heart muscle at 1 h after exposure. The concentration of serum triglycerides increased at 1 h and decreased at 6 h after exposure in fed rats. In these rats, alterations in serum triglycerides correlated with changes in lipoprotein lipase activity in adipose tissue. Alterations observed at the later time periods were more dependent on the time interval between irradiation and the analysis. Lipoprotein lipase activity increased with time after irradiation up to the maximal values at 72 h. Fasting prior to and after irradiation substantially modified the response of animals to radiation. (author)

  5. A comparison of dose-response models for death from hematological depression

    International Nuclear Information System (INIS)

    Morris, M.D.; Jones, T.D.

    1987-01-01

    Many radiation-induced lethality experiments that have been published for various mammalian species have been compiled into a database suitable to study interspecific variability of radiosensitivity, dose-rate dependence of sensitivity, dose-response behavior within each experiment, etc. The data compiled were restricted to continuous and nearly continuous exposures to photon radiations having source energies above 100 keV. Also, photon source energy, exposure geometry, and body weight considerations were used to select studies where the dose to hematopoietic marrow was nearly uniform, i.e., < +- 20%. The data base reflects 13 mammalian test species ranging from mouse to cattle. Some 211 studies were compiled but only 105 were documented in adequate detail to be useful in development and evaluation of dose-response models of interest to practical human exposures. Of the 105 studies, 70 were for various rodent species, and 35 were for nonrodent groups ranging from standard laboratory primates (body weight ∼5 kg) to cattle (body weight 375 kg). This paper considers seven different dose-response models which are tested for validity against those 105 studies. The dose-response models included: a right-skewed extreme value, a left-skewed extreme value model, log-logistic, log-probit, logistic, probit, and Weibull models. In general, the log transformed models did not improve model performance and the extreme value models did not seem consistent with the preponderance of the data. Overall, the probit and the logistic models seemed preferable over the Weibull model. 30 refs., 8 tabs

  6. ‘Candidatus Phytoplasma palmicola’, a novel taxon associated with a lethal yellowing-type disease (LYD) of coconut (Cocos nucifera L.) in Mozambique

    Science.gov (United States)

    In this study, the taxonomic position and group classification of the phytoplasma associated with a lethal yellowing-type disease (LYD) of coconut (Cocos nucifera L.) in Mozambique were addressed. Pairwise sequence similarity values based on alignment of near full-length 16SrRNA genes (1530 bp) reve...

  7. Sub-lethal toxicity of chlorpyrifos on Common carp, Cyprinus carpio (Linnaeus, 1758: Biochemical response

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-01-01

    Full Text Available Chlorpyrifos, an organophosphate pesticide, is widely used to control pests in agriculture farms and orchards of fruit trees. In this study, the fish were exposed to sub-lethal concentrations of chlorpyrifos which were determined based on numerical value of 96 h LC50. Blood was sampled after 10, 20 and 30 days and biochemical parameters including glucose, total protein, albumin, globulin, triglyceride and cholesterol levels, and aspartate aminotransferase (AST, alanine aminotransferase (ALT, lactate dehydrogenase (LDH, creatine kinase (CK, alkaline phosphatase (ALP and acetylcholinsetrase (AChE activities were measured. Behavioral changes in the fish were also recorded during the experiment. Unbalanced swimming, swimming in the surface water and hyperglycemia, increased blood triglyceride, and increased levels of AST, LDH and CK activities as well as decreased levels of AChE activity were important changes that were observed in the specimens exposed to chlorpyrifos during experimental periods. The most important alterations in the blood biochemical parameters were measured in the specimens exposed to 40 µg/L chlorpyrifos on the 20th and 30th day of the trial. In conclusion, results of the present study indicated that exposure to sub-lethal concentrations of chlorpyrifos as low as 40 µg/L may cause biochemical and behavioral changes in Cyprinus carpio.

  8. Seed irradiation with continuously increasing doses of thermal neutrons

    International Nuclear Information System (INIS)

    Uhlik, J.; Pfeifer, M.; Pittermann, P.

    1977-01-01

    In the 'Raman' pea cv. the biological activity of thermal neutrons was investigated after irradiation of a 780 mm column of seeds for 3000 and 4167 seconds with a flux of 5.607 x 10 9 n.cm -2 per second. For different fractions of the seed column the average density of the neutron flux was calculated. It was proved that for the described method of seed irradiation it was sufficient to determine only the dose approaching the lethal dose. If a sufficiently high column of seeds is used part of the column of seeds will be irradiated with the optimum range of doses. The advantages of the suggested method of irradiation are not only smaller time and technological requirements resulting from the need for the determination of only the critical lethal dose of radiation by means of inhibition tests performed with seedlings, but also a simpler irradiation procedure. The suggested method of irradiation is at least nine times cheaper. (author)

  9. [Bladder tumor lethality. Results in the autonomous community of Rioja between 1975-1991].

    Science.gov (United States)

    Fernández Fernández, A; Gil Fabra, J; Fernández Ruíz, M; Angulo Castellanos, M G; Blanco Martín, E; Otero Mauricio, G

    1998-01-01

    Between 1975-1991, a total of 557 cases of bladder carcinoma were identified in the Autonomous Community of La Rioja (CAR) which were followed up to December 1994. The overall lethality was 21.9%. 492 cases with 22.35% lethality were identified in males. In females, however, there was 65 cases with 18.46% lethality. The comparison of males and females lethality resulted in p = 0.525. Lethality between cases diagnosed within each 5-year period analyzed is: 1975-1981: 177 cases, lethality 23.72%. 1982-1986: 168 cases, lethality 30.95%. 1987-1991: 212 cases, lethality 13.20%. Between the first and the second 5-year periods, p = 0.132; between the first and third 5-year periods p = 0.007 and between the second and third 5-year periods p CAR for a 22.35% lethality. Lethality is higher in males that in females but the difference is not statistically significant. In the last 5-year period assessed, 1987-1991, a reduction of lethality from bladder neoplasms has been documented.

  10. Tissue responses to low protracted doses of high LET radiations or photons: Early and late damage relevant to radio-protective countermeasures

    Science.gov (United States)

    Ainsworth, E. J.; Afzal, S. M. J.; Crouse, D. A.; Hanson, W. R.; Fry, R. J. M.

    Early and late murine tissue responses to single or fractionated low doses of heavy charged particles, fission-spectrum neutrons or gamma rays are considered. Damage to the hematopoietic system is emphasized, but results on acute lethality, host response to challenge with transplanted leukemia cells and life-shortening are presented. Low dose rates per fraction were used in some neutron experiments. Split-dose lethality studies (LD 50/30) with fission neutrons indicated greater accumulation of injury during a 9 fraction course (over 17 days) than was the case for γ-radiation. When total doses of 96 or 247 cGy of neutrons or γ rays were given as a single dose or in 9 fractions, a significant sparing effect on femur CFU-S depression was observed for both radiation qualities during the first 11 days, but there was not an earlier return to normal with dose fractionation. During the 9 fraction sequence, a significant sparing effect of low dose rate on CFU-S depression was observed in both neutron and γ-irradiated mice. CFU-S content at the end of the fractionation sequence did not correlate with measured LD 50/30. Sustained depression of femur and spleen CFU-S and a significant thrombocytopenia were observed when a total neutron dose of 240 cGy was given in 72 fractions over 24 weeks at low dose rates. The temporal aspects of CFU-S repopulation were different after a single versus fractionated neutron doses. The sustained reduction in the size of the CFU-S population was accompanied by an increase in the fraction in DNA synthesis. The proliferation characteristics and effects of age were different for radial CFU-S population closely associated with bone, compared with the axial population that can be readily aspirated from the femur. In aged irradiated animals, the CFU-S proliferation/redistribution response to typhoid vaccine showed both an age and radiation effect. After high single doses of neutrons or γ rays, a significant age- and radiation-related deficiency

  11. Sub-lethal irradiation of human colorectal tumor cells imparts enhanced and sustained susceptibility to multiple death receptor signaling pathways.

    Directory of Open Access Journals (Sweden)

    Victoria Ifeadi

    Full Text Available BACKGROUND: Death receptors (DR of the TNF family function as anti-tumor immune effector molecules. Tumor cells, however, often exhibit DR-signaling resistance. Previous studies indicate that radiation can modify gene expression within tumor cells and increase tumor cell sensitivity to immune attack. The aim of this study is to investigate the synergistic effect of sub-lethal doses of ionizing radiation in sensitizing colorectal carcinoma cells to death receptor-mediated apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: The ability of radiation to modulate the expression of multiple death receptors (Fas/CD95, TRAILR1/DR4, TRAILR2/DR5, TNF-R1 and LTβR was examined in colorectal tumor cells. The functional significance of sub-lethal doses of radiation in enhancing tumor cell susceptibility to DR-induced apoptosis was determined by in vitro functional sensitivity assays. The longevity of these changes and the underlying molecular mechanism of irradiation in sensitizing diverse colorectal carcinoma cells to death receptor-mediated apoptosis were also examined. We found that radiation increased surface expression of Fas, DR4 and DR5 but not LTβR or TNF-R1 in these cells. Increased expression of DRs was observed 2 days post-irradiation and remained elevated 7-days post irradiation. Sub-lethal tumor cell irradiation alone exhibited minimal cell death, but effectively sensitized three of three colorectal carcinoma cells to both TRAIL and Fas-induced apoptosis, but not LTβR-induced death. Furthermore, radiation-enhanced Fas and TRAIL-induced cell death lasted as long as 5-days post-irradiation. Specific analysis of intracellular sensitizers to apoptosis indicated that while radiation did reduce Bcl-X(L and c-FLIP protein expression, this reduction did not correlate with the radiation-enhanced sensitivity to Fas and/or TRAIL mediated apoptosis among the three cell types. CONCLUSIONS/SIGNIFICANCE: Irradiation of tumor cells can overcome Fas and TRAIL

  12. Dose limits

    International Nuclear Information System (INIS)

    Fitoussi, L.

    1987-12-01

    The dose limit is defined to be the level of harmfulness which must not be exceeded, so that an activity can be exercised in a regular manner without running a risk unacceptable to man and the society. The paper examines the effects of radiation categorised into stochastic and non-stochastic. Dose limits for workers and the public are discussed

  13. The Value of Value

    DEFF Research Database (Denmark)

    Sørensen, Asger

    parts of business ethics given prominence to especially one term, namely `value'. The question that interests me is the following: What does the articulation of ethics and morality in terms of values mean for ethics and morality as such. Or, to put the question in a more fashionably way: What......As a social scientist of ethics and morality, Luhmann has noticed the ethical wave that has recently swept across the western world, and states that this particular kind of wave seems to have a wavelength of about one hundred years (cf. Luhmann 1989: 9 ff.). Even though the frequency...... and the regularity of such a phenomenon is both hard to verify and, if true, difficult to explain, it seems fair to say that since the Enlightenment, an approaching fin-de-siecle has brought an increased interest in matters concerning morality and ethics.1 The present peak has in public-political discourse and some...

  14. Structure and novel functional mechanism of Drosophila SNF in sex-lethal splicing.

    Directory of Open Access Journals (Sweden)

    Jicheng Hu

    Full Text Available Sans-fille (SNF is the Drosophila homologue of mammalian general splicing factors U1A and U2B'', and it is essential in Drosophila sex determination. We found that, besides its ability to bind U1 snRNA, SNF can also bind polyuridine RNA tracts flanking the male-specific exon of the master switch gene Sex-lethal (Sxl pre-mRNA specifically, similar to Sex-lethal protein (SXL. The polyuridine RNA binding enables SNF directly inhibit Sxl exon 3 splicing, as the dominant negative mutant SNF(1621 binds U1 snRNA but not polyuridine RNA. Unlike U1A, both RNA recognition motifs (RRMs of SNF can recognize polyuridine RNA tracts independently, even though SNF and U1A share very high sequence identity and overall structure similarity. As SNF RRM1 tends to self-associate on the opposite side of the RNA binding surface, it is possible for SNF to bridge the formation of super-complexes between two introns flanking Sxl exon 3 or between a intron and U1 snRNP, which serves the molecular basis for SNF to directly regulate Sxl splicing. Taken together, a new functional model for SNF in Drosophila sex determination is proposed. The key of the new model is that SXL and SNF function similarly in promoting Sxl male-specific exon skipping with SNF being an auxiliary or backup to SXL, and it is the combined dose of SXL and SNF governs Drosophila sex determination.

  15. Hormone-dependence of sarin lethality in rats: Sex differences and stage of the estrous cycle

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Carl D., E-mail: carl.d.smith179.mil@mail.mil; Wright, Linnzi K.M.; Garcia, Gregory E.; Lee, Robyn B.; Lumley, Lucille A.

    2015-09-15

    Chemical warfare nerve agents (CWNAs) are highly toxic compounds that cause a cascade of symptoms and death, if exposed casualties are left untreated. Numerous rodent models have investigated the toxicity and mechanisms of toxicity of CWNAs, but most are limited to male subjects. Given the profound physiological effects of circulating gonadal hormones in female rodents, it is possible that the daily cyclical fluctuations of these hormones affect females' sensitivity to the lethal effects of CWNAs, and previous reports that included female subjects did not control for the stage of the hormonal cycle. The aim of the current study was to determine the 24-hour median lethal dose (LD{sub 50}) of the CWNA sarin in male, ovariectomized (OVEX) female, and female rats during different stages of the estrous cycle (diestrus, proestrus, and estrus). Additionally, baseline activity levels of plasma acetylcholinesterase, butyrylcholinesterase, and carboxylesterase were measured to determine differences among the groups. Results indicated that females in proestrus had a significantly higher LD{sub 50} of sarin compared to OVEX and estrous females. Although some sex differences were observed in the activity levels of plasma esterases, they were not consistent and likely not large enough to significantly affect the LD{sub 50}s. These results suggest that hormonal cyclicity can influence the outcome of CWNA-related studies using female rodents, and that this variability can be minimized by controlling for the stage of the cycle. Additional research is necessary to determine the precise mechanism of the observed differences because it is unlikely to be solely explained by plasma esterase activity. - Highlights: • The LD{sub 50} of sarin was determined in female rats throughout the stages of the estrous cycle. • Females in proestrus had a significantly higher LD{sub 50} compared to estrous or ovariectomized females. • No sex differences were observed between male and female

  16. Changes in activities of adaptive liver enzymes in rats after non-lethal x-irradiation

    International Nuclear Information System (INIS)

    Toropila, M.; Ahlersova, E.; Ahlers, I.; Benova, K.

    1998-01-01

    The effect of a single dose of whole-body X-irradiation of 2.39 Gy (250 R) on the activities of selected adaptive rat liver enzymes and blood serum corticosterone concentrations was followed for a period of 28 days. Rats of Wistar strain SPF breeding (VELAZ Prague) were used. Both irradiated and control animals were fed in pairs with the same amount of feed as was consumed by irradiated animals in the pilot experiment. The feed intake of irradiated animals decreased significantly until the fourth day. During the rest of the experimental period no significant differences were recorded in feed intake between the experimental and control groups. The activity of tyrosine aminotransferase (TAT) in the liver of irradiated animals increased, with the exception of the initial period. Similar changes were recorded in the activity of tryptophane-2-3 dioxygenase (TO). A significant increase on the third day and a significant decrease from the seventh day after irradiation was recorded in the activity of aspartate aminotransferase (AST). Similar changes were observed with alanine aminotransferase (ALT). It is necessary to stress that the activity of this enzyme decreased also on the first day after irradiation. Until the third day there was a marked increase of serum corticosterone in the irradiated animals. The results point not only towards significant changes to the parameters observed, caused by a non-lethal irradiation dose, but also towards the importance of the nutritional regime, so-called paired feeding

  17. Repair of potentially lethal and sublethal radiation damage in x-irradiated ascites tumor cells

    International Nuclear Information System (INIS)

    Tsuboi, Atsushi; Okamoto, Mieko; Tsuchiya, Takehiko.

    1985-01-01

    The ability of cells to repair cellular radiation damage during the growth of TMT-3 ascites tumor and the effect of host reaction on the repair ability were examined by using an in vitro assay of cell clonogenicity after in situ irradiation of tumor cells. In single-dose experiments, the repair of potentially lethal radiation damage (PLD) was observed in stationary phase cells (12-day tumor) of the unirradiated host, but not in exponential phase cells (3-day tumor) of the unirradiated host animals. However, if previously irradiated host animals were used, even the exponentially growing tumor cells showed repair of PLD. In two-dose experiments, the ability to repair sublethal radiation damage (SLD) in exponential phase tumor cells was less than that of stationary phase cells in the unirradiated host. In the pre-irradiated host, the extent of the repair in exponential phase cells was somewhat enhanced. These results suggest that irradiation of host animals might suppress a factor that inhibits repair, resulting in enhancement of the repair capability of tumor cells. (author)

  18. Pretreatment with ascorbic acid prevents lethal gastrointestinal syndrome in mice receiving a massive amount of radiation

    International Nuclear Information System (INIS)

    Yamamoto, Tetsuo; Kinoshita, Manabu; Shinomiya, Nariyoshi; Hiroi, Sadayuki; Sugasawa, Hidekazu; Majima, Takashi; Seki, Shuhji; Matsushita, Yoshitaro; Saitoh, Daizoh

    2010-01-01

    While bone marrow or stem cell transplantation can rescue bone marrow aplasia in patients accidentally exposed to a lethal radiation dose, radiation-induced irreversible gastrointestinal damage (GI syndrome) is fatal. We investigated the effects of ascorbic acid on radiation-induced GI syndrome in mice. Ascorbic acid (150 mg/kg/day) was orally administered to mice for 3 days, and then the mice underwent whole body irradiation (WBI). Bone marrow transplantation (BMT) 24 h after irradiation rescued mice receiving a WBI dose of less than 12 Gy. No mice receiving 14 Gy-WBI survived, because of radiation-induced GI syndrome, even if they received BMT. However, pretreatment with ascorbic acid significantly suppressed radiation-induced DNA damage in the crypt cells and prevented denudation of intestinal mucosa; therefore, ascorbic acid in combination with BMT rescued mice after 14 Gy-WBI. DNA microarray analysis demonstrated that irradiation up-regulated expressions of apoptosis-related genes in the small intestine, including those related to the caspase-9-mediated intrinsic pathway as well as the caspase-8-mediated extrinsic pathway, and down-regulated expressions of these genes in ascorbic acid-pretreated mice. Thus, pretreatment with ascorbic acid may effectively prevent radiation-induced GI syndrome. (author)

  19. Induction of lethal mutations in the x-chromosome of unirradiated Drosophila oocytes after fertilization by irradiated spermatozoa

    International Nuclear Information System (INIS)

    Shaposhnikov, M.V.; Zainullin, V.G.

    2003-01-01

    Full text: In primary study on Drosophila it was found that irradiated male X-chromosomes induce recessive lethals in unirradiated female homologues (Abeleva et al., 1961, Radiobiologya. 1:123-126). The same effects were obtained in Drosophila in some recent investigations. The mechanisms of these effects is unknown. However it may be responsible for low-dose radiation effects as it induce mutations in unirradiated DNA. We assume that this effect may be a result of activation of error prone repair in response to preliminary DNA lesions in irradiated chromosome. In this research we analyse the frequencies of the recessive lethal mutations in the X-chromosome of Drosophila females mated with irradiated Basc males. We used acute irradiation with a dose rate of 10 Gy. For testing our hypothesis we use the mus209 and mei-41 mutant females. Mus209 is a PCNA gene homologue and mei-41 is a homologue of ATM gene. These genes are involved in post-replication DNA repair which may be error prone repair in Drosophila. It was obtained the tendency to decreasing the mutation rate at the mei-41[D5] background and decreasing mutation rate in mus209[B1] background in comparison with wild type strains CS (p<0.05). The obtained results demonstrate the possible role of mus209[B1] and mei-41[D5] genes in the inducing of mutations in the unirradiated X-chromosome in the presence of irradiated homologue

  20. Blue light induced reactive oxygen species from flavin mononucleotide and flavin adenine dinucleotide on lethality of HeLa cells.

    Science.gov (United States)

    Yang, Ming-Yeh; Chang, Chih-Jui; Chen, Liang-Yü

    2017-08-01

    Photodynamic therapy (PDT) is a safe and non-invasive treatment for cancers and microbial infections. Various photosensitizers and light sources have been developed for clinical cancer therapies. Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are the cofactor of enzymes and are used as photosensitizers in this study. Targeting hypoxia and light-triggering reactive oxygen species (ROS) are experimental strategies for poisoning tumor cells in vitro. HeLa cells are committed to apoptosis when treated with FMN or FAD and exposed to visible blue light (the maximum emitted wavelength of blue light is 462nm). Under blue light irradiation at 3.744J/cm 2 (=0.52mW/cm 2 irradiated for 2h), the minimal lethal dose is 3.125μM and the median lethal doses (LD 50 ) for FMN and FAD are 6.5μM and 7.2μM, respectively. Individual exposure to visible blue light irradiation or riboflavin photosensitizers does not produce cytotoxicity and no side effects are observed in this study. The western blotting results also show that an intrinsic apoptosis pathway is activated by the ROS during photolysis of riboflavin analogues. Blue light triggers the cytotoxicity of riboflavins on HeLa cells in vitro. Based on these results, this is a feasible and efficient of PDT with an intrinsic photosensitizer for cancer research. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Poly(ADP-ribose) metabolism in X-irradiated Chinese hamster cells: its relation to repair of potentially lethal damage

    International Nuclear Information System (INIS)

    Ben-Hur, E.; Elkind, M.M.

    1984-01-01

    Nicotinamide-adenine dinucleotide (NAD + ) is the substrate used by cells in poly(ADP-ribose) synthesis. X-irradiation of log-phase Chinese hamster cells caused a rapid decrease in NAD + levels which was linearly dependent on radiation dose. The activity of ADP-ribosyl transferase (ADPRT) also increased linearly with radiation dose. The decrease of NAD + was slower, and the increase in ADPRT activity was less pronounced, in a radiation sensitive line, V79-AL162/S-10. An inhibitor of ADPRT, m-aminobenzamide, largely prevented the depletion of cellular NAD + and reduced the rate at which ADPRT activity disappeared during post-irradiation incubation. Post-irradiation treatment with hypertonic buffer or with medium containing D 2 O-which inhibit repair of radiation-induced potentially lethal damage-enhanced the depletion of NAD + and prevented the reduction in ADPRT activity following irradiation. The characteristics of the effects of treatment with hypertonic buffer on NAD + metabolism were qualitatively similar to the effects that such treatment has on radiation-induced cell killing. These results suggest that poly(ADP-ribose) synthesis after irradiation plays a role in the repair of potentially lethal damage. (author)

  2. The patient dose survey and dose reduction in diagnostic radiology

    International Nuclear Information System (INIS)

    Dang Thanh Luong; Duong Van Vinh; Ha Ngoc Thach

    2000-01-01

    This paper presented the results of the patient dose survey in some hospitals in Hanoi from 1995 to 1997. The main investigated types of the X-ray examination were: Chest PA, LAT; Skull PA/AP, LAT; Lumbar spine AP, LAT; and Pelvis AP. The fluctuation of the entrance surface doses (ESD) was too large, even in the same type of X-ray examination and X-ray facility. It was found that the ratio of maximum and minimum ESD were ranged from 1.5 to 18. The mean values of ESD for chest and skull were higher than CEC recommended values, while the mean values of lumbar spine and pelvis were smaller than that of CEC recommended values. The result of dose intercomparison was also reported. Some methods of dose reduction were applied for improving the patient dose in X-ray departments such as a high kV technique, high sensitive screen-film combination. (author)

  3. Prevention of lethal graft-versus-host disease in mice by monoclonal antibodies directed against T cells or their subsets.I.Evidence for the induction of a state of tolerance based on suppression

    NARCIS (Netherlands)

    Knulst, A.C.; Tibbe, G.J.M.; Noort, W.A.; Bril-Bazuin, C.; Benner, R.; Savelkoul, H.F.J.

    1994-01-01

    Lethal GVHD in the fully allogeneic BALB/c (donor)-(C57BL x CBA)F1 (recipient) mouse strain combination could be prevented by a single dose of IgG2b monoclonal antibodies (moAb) directed to T cells. The influence of the time of administration of this moAb after GVHD induction and the effect of

  4. Ultraviolet-B lethal damage on Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Degiorgi, C.F.; Fernandez, R.O.; Pizarro, R.A.

    1996-01-01

    Pseudomonas aeruginosa has shown an increased sensitivity compared with that of Escherichia coli and Enterobacter cloacae, when they were exposed to 0.4 kJ/m2 of ultraviolet-B radiation. The rapid decay in cell viability observed in Pseudomonas aeruginosa after the irradiation was influenced by factors such as culture media and the presence of pyocyanine during the irradiation. The radioinduced lethal damage could be prevented by photoreactivating treatment, indicating that pyrimidine dimer formation was the mechanism causing bacterial death. The results indicate that several environmental conditions may act as protective agents against ultraviolet-B-induced damage

  5. Metformin is synthetically lethal with glucose withdrawal in cancer cells.

    Science.gov (United States)

    Menendez, Javier A; Oliveras-Ferraros, Cristina; Cufí, Sílvia; Corominas-Faja, Bruna; Joven, Jorge; Martin-Castillo, Begoña; Vazquez-Martin, Alejandro

    2012-08-01

    Glucose deprivation is a distinctive feature of the tumor microecosystem caused by the imbalance between poor supply and an extraordinarily high consumption rate. The metabolic reprogramming from mitochondrial respiration to aerobic glycolysis in cancer cells (the "Warburg effect") is linked to oncogenic transformation in a manner that frequently implies the inactivation of metabolic checkpoints such as the energy rheostat AMP-activated protein kinase (AMPK). Because the concept of synthetic lethality in oncology can be applied not only to genetic and epigenetic intrinsic differences between normal and cancer cells but also to extrinsic ones such as altered microenvironment, we recently hypothesized that stress-energy mimickers such as the AMPK agonist metformin should produce metabolic synthetic lethality in a glucose-starved cell culture milieu imitating the adverse tumor growth conditions in vivo. Under standard high-glucose conditions, metformin supplementation mostly caused cell cycle arrest without signs of apoptotic cell death. Under glucose withdrawal stress, metformin supplementation circumvented the ability of oncogenes (e.g., HER2) to protect breast cancer cells from glucose-deprivation apoptosis. Significantly, representative cell models of breast cancer heterogeneity underwent massive apoptosis (by >90% in some cases) when glucose-starved cell cultures were supplemented with metformin. Our current findings may uncover crucial issues regarding the cell-autonomous metformin's anti-cancer actions: (1) The offently claimed clinically irrelevant, non-physiological concentrations needed to observe the metformin's anti-cancer effects in vitro merely underlie the artifactual interference of erroneous glucose-rich experimental conditions that poorly reflect glucose-starved in vivo conditions; (2) the preferential killing of cancer stem cells (CSC) by metformin may simply expose the best-case scenario for its synthetically lethal activity because an increased

  6. Genotoxicity test of irradiated spice mixture by dominant lethal test

    Energy Technology Data Exchange (ETDEWEB)

    Barna, J

    1986-03-01

    Dominant lethal test (DLT) was performed in Sprague Dawley male rats prefed with 25% irradiated spice mixture which was composed of 55% non-pungent ground paprika, 14% black pepper, 9% allspice, 9% coriander, 7% marjoram, 4% cumin, 2% nutmeg. Microbial count of the spice mixture was reduced with 15 kGy from a sup(60)Co source. Control groups received spice-free or untreated spice diet or were administered to cyclophosphamide i.p., respectively. DTL parameters altered significantly in the latter group but neither untreated nor irradiated spice mixture proved to be germ cell mutagens. 24 refs.; 8 figs.

  7. Lethal subarachnoid bleeding under immunosuppressive therapy due to mycotic arteritis

    International Nuclear Information System (INIS)

    Weigel, S.; Kloska, S.; Freund, M.; Kehl, H.G.

    2003-01-01

    A subarachnoid haemorrhage (SAH) occurred 67 days after cardiac transplantation in 10-year-old girl with consecutive immunocompromising therapy. Neither digital subtraction angiography (DSA) nor computed tomographic angiography showed signs of intracranial vascular malformations. One month before the lethal SAH occurred, she had developed arterial hypertension and attacks of severe headache with cerebrospinal fluid (CSF) pleocytosis while CT scans showed an infarct of the left thalamus. Pathologic findings established the rare diagnosis of SAH due to aspergillosis-related mycotic arteritis. Imaging characteristics are presented. (orig.)

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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