WorldWideScience

Sample records for irradiance exposure factors

  1. Chronic radiation exposure as an ecological factor: Hypermethylation and genetic differentiation in irradiated Scots pine populations

    International Nuclear Information System (INIS)

    Volkova, P.Yu.; Geras'kin, S.A.; Horemans, N.; Makarenko, E.S.; Saenen, E.; Duarte, G.T.; Nauts, R.; Bondarenko, V.S.; Jacobs, G.; Voorspoels, S.; Kudin, M.

    2018-01-01

    Genetic and epigenetic changes were investigated in chronically irradiated Scots pine (Pinus sylvestris L.) populations from territories that were heavily contaminated by radionuclides as result of the Chernobyl Nuclear Power Plant accident. In comparison to the reference site, the genetic diversity revealed by electrophoretic mobility of AFLPs was found to be significantly higher at the radioactively contaminated areas. In addition, the genome of pine trees was significantly hypermethylated at 4 of the 7 affected sites. - Highlights: • Chronic radiation exposure changes the genetic structure of plant populations. • Genomes of irradiated pines are hypermethylated. • The level of hypermethylation does not depend on annual dose. - These results indicate that even relatively low levels of chronic radiation exposure can influence on the genetic characteristics and the methylation status of natural pine populations and that it should be considered as an important ecological factor reflecting the anthropogenic impact on ecosystems.

  2. Analysis of the risk factors for exposure of the lung to low irradiation doses

    International Nuclear Information System (INIS)

    Hogeweg, B.

    1986-02-01

    In this report a description is presented of the risk factors for induction of lungtumours. The contribution of natural radioactivity from uranium and thorium to the lungs is mainly caused by inhalation of alpha-emitting radon and thorium daughter products. Apart from exposure by inhalation the lungs are also exposed to external radiation. For internal as well as external exposure a value of 10 -3 lungcancers per Sv lung dose equivalence is found to be acceptable for the riskfactor. (Auth.)

  3. Chronic radiation exposure as an ecological factor: Hypermethylation and genetic differentiation in irradiated Scots pine populations.

    Science.gov (United States)

    Volkova, P Yu; Geras'kin, S A; Horemans, N; Makarenko, E S; Saenen, E; Duarte, G T; Nauts, R; Bondarenko, V S; Jacobs, G; Voorspoels, S; Kudin, M

    2018-01-01

    Genetic and epigenetic changes were investigated in chronically irradiated Scots pine (Pinus sylvestris L.) populations from territories that were heavily contaminated by radionuclides as result of the Chernobyl Nuclear Power Plant accident. In comparison to the reference site, the genetic diversity revealed by electrophoretic mobility of AFLPs was found to be significantly higher at the radioactively contaminated areas. In addition, the genome of pine trees was significantly hypermethylated at 4 of the 7 affected sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Reparation in unicellular green algae during chronic exposure to the action of mutagenic factors. II. Restoration of single-stranded DNA breaks following exposure of Chlamydomonas reinchardii to gamma-irradiation

    International Nuclear Information System (INIS)

    Sergeeva, S.A.; Ptitsina, S.N.; Shevchenko, V.A.

    1986-01-01

    The restoration of single-stranded breaks in the DNA in different strains of unicellular green algae (chlamydomonads) during chronic exposure to the action of mutagenic factors following γ-irradiation was investigated. It was shown that the restoration of DNA breaks was most effective in the case of strain M γ/sup mt + /, which is resistant to radiation. Strains, that were sensitive to UV irradiation showed a similar order of DNA break restoration as the wild-type strain. Strain UVS-1 showed a higher level of restoration than the wild-type strain. The data indicated that chlamydomonads have different pathways of reparation, which lead to the restoration of breaks induced by γ-irradiation and UV-rays

  5. Irradiation exposure modulates central opioid functions

    International Nuclear Information System (INIS)

    Dougherty, P.M.; Dafny, N.

    1987-01-01

    Exposure to low doses of gamma irradiation results in the modification of both the antinociceptive properties of morphine and the severity of naloxone-precipitated withdrawal in morphine-dependent rats. To better define the interactions between gamma irradiation and these opiate-mediated phenomena, dose-response studies were undertaken of the effect of irradiation on morphine-induced antinociception, and on the naloxone-precipitated withdrawal syndrome of morphine-dependent rats. In addition, electrophysiologic studies were conducted in rats after irradiation exposure and morphine treatment correlating with the behavioral studies. The observations obtained demonstrated that the antinociceptive effects of morphine as well as naloxone-precipitated withdrawal were modified in a dose-dependent manner by irradiation exposure. In addition, irradiation-induced changes in the evoked responses obtained from four different brain regions demonstrated transient alterations in both baseline and morphine-treated responses that may reflect the alterations observed in the behavioral paradigms. These results suggest that the effects of irradiation on opiate activities resulted from physiologic alterations of central endogenous opioid systems due to alterations manifested within peripheral targets

  6. Irradiation exposure modulates central opioid functions

    Energy Technology Data Exchange (ETDEWEB)

    Dougherty, P.M.; Dafny, N.

    1987-11-01

    Exposure to low doses of gamma irradiation results in the modification of both the antinociceptive properties of morphine and the severity of naloxone-precipitated withdrawal in morphine-dependent rats. To better define the interactions between gamma irradiation and these opiate-mediated phenomena, dose-response studies were undertaken of the effect of irradiation on morphine-induced antinociception, and on the naloxone-precipitated withdrawal syndrome of morphine-dependent rats. In addition, electrophysiologic studies were conducted in rats after irradiation exposure and morphine treatment correlating with the behavioral studies. The observations obtained demonstrated that the antinociceptive effects of morphine as well as naloxone-precipitated withdrawal were modified in a dose-dependent manner by irradiation exposure. In addition, irradiation-induced changes in the evoked responses obtained from four different brain regions demonstrated transient alterations in both baseline and morphine-treated responses that may reflect the alterations observed in the behavioral paradigms. These results suggest that the effects of irradiation on opiate activities resulted from physiologic alterations of central endogenous opioid systems due to alterations manifested within peripheral targets.

  7. Physical properties of irradiation exposured food

    International Nuclear Information System (INIS)

    Hayashi, Toru; Todoroki, Setsuko; Kono, Sumio; Kikuchi, Yuji; Otobe, Kazunori

    1997-01-01

    A distinguishing method of irradiation effects on white and black pepper was established by using measurement of viscosity. This method makes possible to distinguish the irradiated pepper independent on the place of production, period of storage and kinds of viscometer. The method is described as follows: Add 40 ml of water to 4 g of pepper powder which produces a suspension of pepper in water. 2 ml of 33% caustic solution is added to the suspension, immediatly heating it in boiling water for 30 min for gelatinization. Then, it is permitted to stand for 3.5 hours and measured its viscosity. Amount of starch in pepper sample is determined previously. The obtained viscosity divided by the amount of starch is used as a parameter. (S.Y.)

  8. Lipomatous muscle atrophy caused by irradiation exposure

    International Nuclear Information System (INIS)

    Rhomberg, W.; Hergan, K.

    1990-01-01

    As compared to other organs and tissues liable to sustain delayed injury from radiotherapy, the musculature seems to be a hard-wearing, radiation-resistant organ. Apart from the possibility of inducing Myodegeneratio cordis, muscles are merely threatened, as far as is known today, by possible fibrosis in the surrounding area. Certainly, extremely high doses of more than 100 Gy occasionally may trigger necrosis and atrophies in tissues. The article reports on a patient suffering from carcinoma of the bladder who developed muscle and tendon degeneration following telecobalt irradiation after a latency period of eight years, forcing him ultimately to quit work. (orig.) [de

  9. Irradiation Stability of Uranium Alloys at High Exposures

    International Nuclear Information System (INIS)

    McDonell, W.R.

    2001-01-01

    Postirradiation examinations were begun of a series of unrestrained dilute uranium alloy specimens irradiated to exposures up to 13,000 MWD/T in NaK-containing stainless steel capsules. This test, part of a program of development of uranium metal fuels for desalination and power reactors sponsored by the Division of Reactor Development and Technology, has the objective of defining the temperature and exposure limits of swelling resistance of the alloyed uranium. This paper discusses those test results

  10. Electromagnetic irradiation exposure and its bioindication - An overview

    Institute of Scientific and Technical Information of China (English)

    Osmo H(a)nninen; Paavo Huttunen; Reijo Ekman

    2011-01-01

    Man made electromagnetic irradiation and fields cover now the globe due to the recent extensive propagation of mobile telephony.The increased load affects animals and also plants.Especially birds have been studied.Humans are also sensitive.They are good bioindicators as epidemiological methods are available.Humans can also report symptoms which cannot be directly measured with presently available technologies.The nonionizing irradiation can as the ionizing one break the DNA,damage proteins,even increase the blood brain barrier permeability,disturb the night rest,cause fatigue and hormonal disturbances.An increase of the tumours of human head has been described in correlation with the long term mobile phone use and on that side more exposed.The regulations covering mobile telephony are already about two decades old and need re-evaluation.The multitude of irradiation and the interaction of the different wavelength exposures,i.e.,frequency sensitivity is poorly known at present.We should not forget the comparative studies of different species especially those which rely in their lives on electromagnetic orientation physiology.Some countries have issued warnings on the exposures of children.The producers of mobile technology have recently warned the users not to keep those devices in active stage in skin contact.

  11. Exposure Factors Resources: Contrasting EPA’s Exposure Factors Handbook with International Sources (Journal Article)

    Science.gov (United States)

    Efforts to compile and standardize exposure human factors have resulted in the development of a variety of resources available to the scientific community. For example, the U.S. EPA developed the Exposure Factors Handbook and Child-specific Exposure Factors Handbook to promote c...

  12. Hyperparathyroidism subsequent to neck irradiation. Risk factors

    International Nuclear Information System (INIS)

    Tisell, L.E.; Carlsson, S.; Fjaelling, M.H.; Hansson, G.; Lindberg, S.; Lundberg, L.M.; Oden, A.

    1985-01-01

    A follow-up examination of 444 persons treated with x-rays for tuberculous cervical adenitis was performed to determine if the risk for hyperparathyroidism (HPT) following radiation exposure can be related to the age at treatment, the dose of x-rays, or the sex of the patient. The overall incidence of HPT was 14%. There was no definite age-dependent difference in susceptibility to the induction of HPT. The doses of radiation among the 63 subjects who developed HPT ranged from 0.6 to 45.7 Gy (60-4570 rad). There was a statistically significant positive correlation between the dose of radiation and the probability of developing HPT. After doses of 14 Gy (1400 rad) or more 29% of the subjects had developed HPT. After neck irradiation women had twice the relative risk of men of developing HPT. This sex ratio was lower than in the series of nonirradiated HPT patients treated at the same institution during the time of the follow-up study

  13. Adrenal and plasma corticosterone changes in continuously irradiated rats. II. Dependence on additional stress factors

    Energy Technology Data Exchange (ETDEWEB)

    Malatova, Z; Ahlers, I; Praslicka, M [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

    1978-01-01

    Adrenal and plasma corticosterone levels were followed in continuously irradiated rats in dependence on additional stress factors - transport of animals, handling and overnight fasting. Rats were gamma irradiated on an open experimental field with a daily dose rate of 15.48x10/sup -3/ C/kg (60 R) continuously up to a total exposure of 387.0x10/sup -3/ C/kg (1500 R) and analyzed after irradiation. The continuous irradiation increased the adrenal and plasma corticosterone concentrations in all groups of animals. The transport and weighing increased mainly adrenal corticosterone in all three groups, irradiated, non-irradiated controls from the field and intact laboratory controls. The scatter of the results made reproducibility difficult. Overnight fasting increased the absolute values in all groups. The radiation effect was evident especially in adrenal corticosterone values of non-handled animals.

  14. Water accelerated transformation of d-limonene induced by ultraviolet irradiation and air exposure.

    Science.gov (United States)

    Li, Li Jun; Hong, Peng; Jiang, Ze Dong; Yang, Yuan Fan; Du, Xi Ping; Sun, Hao; Wu, Li Ming; Ni, Hui; Chen, Feng

    2018-01-15

    d-Limonene is a fragrant chemical that widely exists in aromatic products. Isotopic labelling of water molecules plus GC-MS and GC-PCI-Q-TOF analyses were used to investigate the influence of water molecules on chemical transformation of d-limonene induced by UV irradiation and air exposure. The results showed that the synergistic effect of UV irradiation, air exposure and water presence could facilitate d-limonene transformation into the limonene oxides: p-mentha-2,8-dienols, hydroperoxides, carveols, l-carvone and carvone oxide. UV irradiation, air exposure, or water alone, however, caused negligible d-limonene transformation. With the aid of isotopic labelling of water and oxygen molecules, it was found that water molecules were split into hydrogen radicals and hydroxyl radicals, and the hydrogen radicals, in particular, promoted the transformation reactions. This study has elucidated the mechanism and factors that influence the transformation of d-limonene, which will benefit industries involved in production and storage of d-limonene-containing products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Factors affecting practical application of food irradiation

    International Nuclear Information System (INIS)

    1990-04-01

    FAO and IAEA convened an Advisory Group Meeting on Commercial Use of Food Irradiation in order to discuss problems of the industry's acceptance of food irradiation and their remedies. Senior executives from major food industries, trade and consumer organizations were invited to discuss these problems and to prepare a report which would serve as the basis for future plan of action by sponsoring Organizations in the field of food irradiation. This publication contains the report of the meeting, papers presented by the participants and their recommendations to the sponsoring Organizations. Refs and tabs

  16. Transcriptomic analysis of grape (Vitis vinifera L. leaves after exposure to ultraviolet C irradiation.

    Directory of Open Access Journals (Sweden)

    Huifen Xi

    Full Text Available BACKGROUND: Only a small amount of solar ultraviolet C (UV-C radiation reaches the Earth's surface. This is because of the filtering effects of the stratospheric ozone layer. Artificial UV-C irradiation is used on leaves and fruits to stimulate different biological processes in plants. Grapes are a major fruit crop and are grown in many parts of the world. Research has shown that UV-C irradiation induces the biosynthesis of phenols in grape leaves. However, few studies have analyzed the overall changes in gene expression in grape leaves exposed to UV-C. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, transcriptional responses were investigated in grape (Vitis vinifera L. leaves before and after exposure to UV-C irradiation (6 W·m-2 for 10 min using an Affymetrix Vitis vinifera (Grape Genome Array (15,700 transcripts. A total of 5274 differentially expressed probe sets were defined, including 3564 (67.58% probe sets that appeared at both 6 and 12 h after exposure to UV-C irradiation but not before exposure. A total of 468 (8.87% probe sets and 1242 (23.55% probe sets were specifically expressed at these times. The probe sets were associated with a large number of important traits and biological pathways, including cell rescue (i.e., antioxidant enzymes, protein fate (i.e., HSPs, primary and secondary metabolism, and transcription factors. Interestingly, some of the genes involved in secondary metabolism, such as stilbene synthase, responded intensely to irradiation. Some of the MYB and WRKY family transcription factors, such as VvMYBPA1, VvMYB14, VvMYB4, WRKY57-like, and WRKY 65, were also strongly up-regulated (about 100 to 200 fold. CONCLUSIONS: UV-C irridiation has an important role in some biology processes, especially cell rescue, protein fate, secondary metabolism, and regulation of transcription.These results opened up ways of exploring the molecular mechanisms underlying the effects of UV-C irradiation on grape leaves and have

  17. Transcriptomic analysis of grape (Vitis vinifera L.) leaves after exposure to ultraviolet C irradiation.

    Science.gov (United States)

    Xi, Huifen; Ma, Ling; Liu, Guotian; Wang, Nian; Wang, Junfang; Wang, Lina; Dai, Zhanwu; Li, Shaohua; Wang, Lijun

    2014-01-01

    Only a small amount of solar ultraviolet C (UV-C) radiation reaches the Earth's surface. This is because of the filtering effects of the stratospheric ozone layer. Artificial UV-C irradiation is used on leaves and fruits to stimulate different biological processes in plants. Grapes are a major fruit crop and are grown in many parts of the world. Research has shown that UV-C irradiation induces the biosynthesis of phenols in grape leaves. However, few studies have analyzed the overall changes in gene expression in grape leaves exposed to UV-C. In the present study, transcriptional responses were investigated in grape (Vitis vinifera L.) leaves before and after exposure to UV-C irradiation (6 W·m-2 for 10 min) using an Affymetrix Vitis vinifera (Grape) Genome Array (15,700 transcripts). A total of 5274 differentially expressed probe sets were defined, including 3564 (67.58%) probe sets that appeared at both 6 and 12 h after exposure to UV-C irradiation but not before exposure. A total of 468 (8.87%) probe sets and 1242 (23.55%) probe sets were specifically expressed at these times. The probe sets were associated with a large number of important traits and biological pathways, including cell rescue (i.e., antioxidant enzymes), protein fate (i.e., HSPs), primary and secondary metabolism, and transcription factors. Interestingly, some of the genes involved in secondary metabolism, such as stilbene synthase, responded intensely to irradiation. Some of the MYB and WRKY family transcription factors, such as VvMYBPA1, VvMYB14, VvMYB4, WRKY57-like, and WRKY 65, were also strongly up-regulated (about 100 to 200 fold). UV-C irridiation has an important role in some biology processes, especially cell rescue, protein fate, secondary metabolism, and regulation of transcription.These results opened up ways of exploring the molecular mechanisms underlying the effects of UV-C irradiation on grape leaves and have great implications for further studies.

  18. Service factor calculated from an experimental simulation of chronic occupational irradiation

    International Nuclear Information System (INIS)

    Berikashvili, V.Sh.

    1975-01-01

    A correlation has been studied between the body weight, basal metabolism, lifespan, the period of water exchange, average life of erythrocytes and average rate of pulse-beat, and values LDsub(50/30-60), half-recovery period after irradiation and time of leucopenia occurrence in different species of laboratory animals and man. An authentic degree-interrelation of these indices has been revealed, and the dependency of radiobiological effects on the body weight of animals has been estimated. Similarity conditions of dose accumulation upon chronic irradiation of animals and man have been obtained on the basis of Blair's and Davidson's equations for an effective dose of a single exposure. Service factor and coefficients of intensity and duration of irradiation of various animals have been calculated, simulating professional irradiation with 5 rad/a within 20 years

  19. Tumor necrosis factor alpha production in irradiated cells in vitro

    International Nuclear Information System (INIS)

    Koeteles, G.J.; Bognar, G.; Kubasova, T.

    1994-01-01

    Normal and tumor cell lines were used to investigate tumor necrosis factor (TNFα) production and its radiation sensitivity. The cells were irradiated with gamma rays using different doses from 0.25 Gy up to 5 Gy. The number of plated cells, changes of proliferation and TNFα production were determined during the following four post-irradiation days. For TNFα quantity measurement immuno-radiometric assay (IRMA) and enzyme amplified sensitivity assay (EASIA) was used. The results suggest that though gamma irradiation decreased cell proliferation in a dose dependent manner, the quantity produced in the post-irradiation period increased considerably in each irradiated sample. (N.T.) 3 refs.; 2 figs.; 1 tab

  20. Overview of the development of the Korean exposure factors handbook.

    Science.gov (United States)

    Jang, Jae-Yeon; Jo, Soo-Nam; Kim, So-Yeon; Myung, Hyung-Nam

    2014-01-01

    A set of exposure factors that reflects the characteristics of individual behavior capable of influencing exposure is essential for risk and exposure assessment. In 2007, the Korean Exposure Factors Handbook was, therefore, issued, driven by the need to develop reliable exposure factors representing the Korean population. The purpose of this study was to overview the development process of the Korean Exposure Factors Handbook and major recommended exposure values for the Korean population to allow information exchanges and comparison of recommended values among nations. The researchers reviewed the domestic data that could be used in the development of exposure factors, confirmed a knowledge gap, and set a priority of development by phases. A methodology to measure exposure factors was established to develop measuring techniques and test their validity. Data were processed or a survey was conducted according to the availability of data. The study thus produced recommended values for 24 exposure factors grouped by general exposure factors, food ingestion factors, and activity factors by setting up a database of exposure factors and carrying out statistical analysis. The study has significantly contributed to reducing the potential uncertainty of the risk and exposure assessment derived by the application of foreign data or research findings lacking representativeness or grounds by developing a set of exposure factors reflecting the characteristics of the Korean people. It will be necessary to conduct revisions in light of the changing statistical values of national data and the exposure factors based on Korean characteristics.

  1. Management and control aimed at reducing potential exposure of cobalt irradiation units

    International Nuclear Information System (INIS)

    Yan Yukui

    2003-01-01

    This paper is intended to address the problems of the management and control of potential exposure of cobalt irradiation units and analyze both the current situation and the resultant accident reasons associated with irradiation units, with the necessary control measures provided to reduce potential exposure. The concepts of defense in depth and excellent engineering practice are introduced in design to provide the units with sufficient redundancy. In the course of scientific management, the qualified applicants or registers devoted, strictly and effectively, their oversight, monitoring and regulation to the irradiation units. The effective management and control are achieved through safety analysis and assessment, reasonable regulatory system and source decommissioning system. (authors)

  2. Isolation of radiation-resistant bacteria without exposure to irradiation

    International Nuclear Information System (INIS)

    Sanders, S.W.; Maxcy, R.B.

    1979-01-01

    Resistance to desiccation was utilized in the selection of highly radiation-resistant asporogenous bacteria from nonirradiated sources. A bacterial suspension in phosphate buffer was dried in a thin film at 25 0 C and 33% relative humidity. Storage under these conditions for 15 days or more reduced the number of radiation-sensitive bacteria. Further selection for radiation-resistant bacteria was obtained by irradiation of bacteria on velveteen in the replication process, therby avoiding the toxic effect of irradiated media. The similarity of radiation resistance and identifying characteristics in irradiated and non-irradiated isolates should allay some concerns that highly radiation-resistance bacteria have been permanently altered by radiation selection

  3. Determination of epithermal flux correction factor (α) for irradiation ...

    African Journals Online (AJOL)

    Due to resonance that occur in the epithermal energy region of a reactor, the flux spectra in that region deviates strongly from the ideal I/E law to a I/E1+α with alpha as the correction factor. The factor has to be determined if zirconium as monitor pairs to determine the correction factor for inner irradiation channel 5 and outer ...

  4. Exploring Global Exposure Factors Resources for Use in Consumer Exposure Assessments

    Science.gov (United States)

    Zaleski, Rosemary T.; Egeghy, Peter P.; Hakkinen, Pertti J.

    2016-01-01

    This publication serves as a global comprehensive resource for readers seeking exposure factor data and information relevant to consumer exposure assessment. It describes the types of information that may be found in various official surveys and online and published resources. The relevant exposure factors cover a broad range, including general exposure factor data found in published compendia and databases and resources about specific exposure factors, such as human activity patterns and housing information. Also included are resources on exposure factors related to specific types of consumer products and the associated patterns of use, such as for a type of personal care product or a type of children’s toy. Further, a section on using exposure factors for designing representative exposure scenarios is included, along with a look into the future for databases and other exposure science developments relevant for consumer exposure assessment. PMID:27455300

  5. Differential expression of growth factors in irradiated mouse testes

    International Nuclear Information System (INIS)

    Mauduit, Claire; Siah, Ahmed; Foch, Marie; Chapet, Olivier; Clippe, Sebastien; Gerard, Jean-Pierre; Benahmed, Mohamed

    2001-01-01

    Purpose: By using as an experimental model the male mouse gonad, which contains both radiosensitive (germ) and radioresistant (somatic) cells, we have studied the growth factor (and/or receptor) expression of transforming growth factor-β receptor (TGFβ RI), stem cell factor (SCF), c-kit, Fas-L, Fas, tumor necrosis factor receptor (TNF R55), and leukemia inhibiting factor receptor (LIF-R) after local irradiation. Methods and Materials: Adult male mice were locally irradiated on the testes. Induction of apoptosis in the different testicular cell types following X-ray radiation was identified by the TdT-mediated dUTP Nick End Labeling (TUNEL) approach. Growth factor expression was evidenced by semiquantitative RT-PCR and Western blot analyses. Results: Apoptosis, identified through the TUNEL approach, occurred in radiosensitive testicular (premeotic) germ cells with the following kinetics: the number of apoptotic cells increased after 24 h (p<0.001) and was maximal 48 h after a 2-Gy ionizing radiation (p<0.001). Apoptotic cells were no longer observed 72 h after a 2-Gy irradiation. The number of apoptotic cells increased with the dose of irradiation (1-4 Gy). In the seminiferous tubules, the growth factor expression in premeiotic radiosensitive germ cells was modulated by irradiation. Indeed Fas, c-kit, and LIF-R expression, which occurs in (radiosensitive) germ cells, decreased 24 h after a 2-Gy irradiation, and the maximal decrease was observed with a 4-Gy irradiation. The decrease in Stra8 expression occurred earlier, at 4 h after a 2-Gy irradiation. In addition, a significant (p<0.03) decrease in Stra8 mRNA levels was observed at the lowest dose used (0.5 Gy, 48 h). Moreover, concerning a growth factor receptor, such as TGFβ RI, which is expressed both in radiosensitive and radioresistant cells, we observed a differential expression depending on the cell radiosensitivity after irradiation. Indeed, TGFβ RI expression was increased after irradiation in

  6. Relative significance of natural irradiation vs all human exposures

    International Nuclear Information System (INIS)

    Jammet, H.

    1985-01-01

    A review is made of the fundamentals allowing to quantitatively express the importance of the various sources of human exposure by an individual or collective approach. Following a summary of the components of normal exposure to natural sources, the various human actions at the origin of enhanced exposure are studied: 1) those modifying the relationship between natural sources and man (dwelling conditions, coal burning, geothermal energy production, exploitation of phosphate rock); 2) those creating new artificial sources (nuclear explosions in the atmosphere, nuclear power production, medical use of radiation and radionuclides). The effective dose equivalent commitments for these sources are compared with those necessarily involved by continuous normal exposure to the natural sources of exposure [fr

  7. 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.

  8. Food Ingestion Factors of the Korean Exposure Factors Handbook

    Directory of Open Access Journals (Sweden)

    Jae-Yeon Jang

    2014-01-01

    Full Text Available The purpose of this study was to establish food ingestion factors needed to assess exposure to contaminants through food ingestion. The study reclassified the raw data of the Korean National Health and Nutrition Examination Survey in 2001 into 12 subcategories including grain products, meat products, fish and shellfish, and vegetables for international comparability of exposure evaluation. The criteria for food intake calculation were unified according to the characteristics of food groups, and recommended values for food ingestion factors were calculated through moisture correction and recategorization of cooked, processed, and mixed foods for each group. The average intake rate for grain and grain products was 6.25 g/kg-d per capita and the men's intake rate was approximately 8% higher than that of the women. The average intake rate of meat and meat products was 1.62 g/kg-d per capita and the men's intake rate was 30% higher than that of the women, on average. The average intake rate of fish and shellfish was 1.53 g/kg-d per capita, and the age groups of 1 to 2 and 3 to 6 recorded higher capita intake rates than other age groups, 2.62 g/kg-d and 2.25 g/kg-d, respectively. The average intake rate of vegetables was 6.47 g/kg-d per capita, with the age group of 1 to 2 recording the highest per capita intake rate of 9.79 g/kg-d and that of 13 to 19 recording the lowest mean. The study also offers recommended values for food ingestion factors of other food groups by gender, age, and region. The food ingestion exposure factors will need future updates in consideration of ongoing changes in food consumption behavior.

  9. Food ingestion factors of the Korean exposure factors handbook.

    Science.gov (United States)

    Jang, Jae-Yeon; Jo, Soo-Nam; Kim, Sun-Ja; Myung, Hyung-Nam; Kim, Cho-Il

    2014-01-01

    The purpose of this study was to establish food ingestion factors needed to assess exposure to contaminants through food ingestion. The study reclassified the raw data of the Korean National Health and Nutrition Examination Survey in 2001 into 12 subcategories including grain products, meat products, fish and shellfish, and vegetables for international comparability of exposure evaluation. The criteria for food intake calculation were unified according to the characteristics of food groups, and recommended values for food ingestion factors were calculated through moisture correction and recategorization of cooked, processed, and mixed foods for each group. The average intake rate for grain and grain products was 6.25 g/kg-d per capita and the men's intake rate was approximately 8% higher than that of the women. The average intake rate of meat and meat products was 1.62 g/kg-d per capita and the men's intake rate was 30% higher than that of the women, on average. The average intake rate of fish and shellfish was 1.53 g/kg-d per capita, and the age groups of 1 to 2 and 3 to 6 recorded higher capita intake rates than other age groups, 2.62 g/kg-d and 2.25 g/kg-d, respectively. The average intake rate of vegetables was 6.47 g/kg-d per capita, with the age group of 1 to 2 recording the highest per capita intake rate of 9.79 g/kg-d and that of 13 to 19 recording the lowest mean. The study also offers recommended values for food ingestion factors of other food groups by gender, age, and region. The food ingestion exposure factors will need future updates in consideration of ongoing changes in food consumption behavior.

  10. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Juergen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Aaron, A. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bell, Gary L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burgess, Thomas W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ellis, Ronald James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giuliano, D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kiggans, James O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lessard, Timothy L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ohriner, Evan Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Perkins, Dale E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Varma, Venugopal Koikal [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-10-20

    -state heat fluxes of 5–20 MW/m2 and ion fluxes up to 1024 m-2s-1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.

  11. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    International Nuclear Information System (INIS)

    Rapp, Juergen; Aaron, A. M.; Bell, Gary L.; Burgess, Thomas W.; Ellis, Ronald James; Giuliano, D.; Howard, R.; Kiggans, James O.; Lessard, Timothy L.; Ohriner, Evan Keith; Perkins, Dale E.; Varma, Venugopal Koikal

    2015-01-01

    5-20 MW/m"2 and ion fluxes up to 10"2"4 m"-"2s"-"1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.

  12. Exposure amount and timing of solar irradiation during pregnancy and the risk of sensitization in children.

    Science.gov (United States)

    Koh, Hyun Yong; Cho, Eunhae; Lee, So-Yeon; Kim, Woo Kyung; Park, Yong Mean; Kim, Jihyun; Ahn, Kangmo; Lee, Seung Won; Kim, Mi Ae; Hahm, Myung-Il; Chae, Yoomi; Lee, Kee-Jae; Kwon, Ho-Jang; Han, Man Yong

    2018-04-01

    Solar irradiation affects sensitization to aeroallergens and the prevalence of allergic diseases. Little is known, however, about how the time and amount of solar irradiation during pregnancy affects such risks in children. We aimed to find out how solar irradiation during pregnancy affects sensitization to aero-allergens and the prevalence of allergic diseases in children. This population-based cross-sectional study involved 7301 aged 6 years and aged 12 years children. Maternal exposure to solar irradiation during pregnancy was evaluated using data from weather stations closest to each child's birthplace. Monthly average solar irradiation during the second and third trimesters was calculated with rank by quartiles. Risks of allergic sensitization and allergic disease were estimated. Relative to the first (lowest) quartile, the adjusted odds ratio (aOR) for allergic sensitization in the fourth (highest) quartile was lowest within solar irradiation during pregnancy months 5-6 (aOR = 0.823, 95% CI 0.720-0.942, p solar irradiation (aOR = 1.167, 95% CI 1.022-1.333, p solar irradiation was analyzed as a continuous variable during months 5 (aOR = 0.975, 95% CI 0.962-0.989, p solar irradiation during months 7-8 increased the risk of asthma (aOR = 1.309, 95% CI 1.024-1.674, p = 0.032). Maternal exposure to solar irradiation during the second trimester of pregnancy associated with reduced aeroallergen sensitization, whereas solar irradiation during the third trimester was related to increased sensitization to aeroallergens. Copyright © 2017 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

  13. The effect of exposure rate of the growth of soybean seedlings grown from gamma irradiated seeds

    International Nuclear Information System (INIS)

    Mohd Yusof, A.; Grunewald, R.

    1981-01-01

    The effect of the gamma ( 137 Cs) total exposure rate of 25 kR delivered at three different exposure rates (887 R/min, 159 R/min and 48 R/min) on soybean seeds was studied by measuring seedling height, cotyledon area, fresh weight, dry weight, Co 2 fixation and RuDP carboxylase activity. The dry weight, CO 2 fixation and irradiated imbibed groups did not show any correlation with exposure rate. Exposure rate effect was shown for the first stage out, no further correlation was observed in the subsequent stages, probably due to the recovery and repair mechanisms that take place as the seedling increases with age. The absence of an exposure rate effect on irradiated imbibed group may be explained in terms of non-detectable damage at a very high dose, since these seedlings exhibited effects that are similar to the effects of seeds exposed to an acute radiation dose. (author)

  14. Some factors affecting the cost of irradiation services in thailand

    International Nuclear Information System (INIS)

    Kasemsanta, S.

    1985-01-01

    The future of food irradiation in developing countries depends to a large extent on cost considerations. Although food irradiation technology itself is widely known and appears to offer many advantages, concrete evidence on the economic viability of a multi-product irradiation plant is presently not readily available to the private sector in developing countries. It is doubtful whether such evidence exists in a form which is comprehensible to industrialists outside the radiation technology circle. With respect to the economic aspects of food irradiation, information available from the literature appears to be based largely on a summing-up of studies of single products on a case-by-case basis. In an agricultural country, the main inputs to an irradiation service facility are likely to be agricultural produce which vary in kind and quantity with cropping seasons. Moreover, in most developing countries, uncontrollable factors play an important role in the production of annual crops and their transportation. Thus, it is hardly possible to make a credible long term forecast on the throughput required for the multi-product service plant, let alone determine with confidence the return on investment. Accordingly, as far as the private sector is concerned, investment decisions regarding the establishment of a commercial food irradiation service plant have to be considered as 'decision making under risk'. This paper attempts to raise questions to which the author cannot yet find clear and practical answers from the available literature. It is intended to stimulate a more thorough and objective discussion on the subject of economic viability of a multi-product food irradiation plant under the prevailing environment in ASEAN

  15. Assessment of cardiac exposure in left-tangential breast irradiation

    International Nuclear Information System (INIS)

    Vees, H.; Bigler, R.; Gruber, G.; Bieri, S.

    2011-01-01

    Purpose. - To assess the value of treatment-planning related parameters namely, the breast volume; the distance of the inferior field border to diaphragm; and the cardio-thoracic ratio for left-tangential breast irradiation. Patients and methods. - Treatment plans of 27 consecutively left-sided breast cancer patients after breast conserving surgery were evaluated for several parameters concerning heart-irradiation. We measured the heart distance respective to the cardio-thoracic ratio and the distance of the inferior field border to diaphragm, as well as the breast volume in correlation with the irradiated heart volume. Results. - The mean heart and left breast volumes were 504 cm 3 and 672.8 cm 3 , respectively. The mean heart diameter was 13.4 cm; the mean cardio-thoracic ratio 0.51 and the mean distance of the inferior field border to diaphragm was 1.4 cm. Cardio-thoracic ratio (p = 0.01), breast volume (p = 0.0002), distance of the inferior field border to diaphragm (p = 0.02) and central lung distance (p = 0.02) were significantly correlated with the measured heart distance. A significant correlation was also found between cardio-thoracic ratio, breast volume and distance of the inferior field border to diaphragm with the irradiated heart volume measured by V10, V20 and V40. Conclusion. - The verification of parameters like cardio-thoracic ratio, distance of the inferior field border to diaphragm and breast volume in left-sided breast cancer patients may help in determining which patients could benefit from more complex planning techniques such as intensity-modulated radiotherapy to reduced risk of late cardiac injury. (authors)

  16. Child-Specific Exposure Factors Handbook (2008, Final Report)

    Science.gov (United States)

    The National Center for Environmental Assessment Staff (NCEA) have prepared this handbook to provide information on various physiological and behavioral factors commonly used in assessing children’s exposure to environmental chemicals. Children have different exposure circumstanc...

  17. 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.

  18. 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

  19. Patient-based radiographic exposure factor selection: a systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Ching, William; Robinson, John; McEntee, Mark, E-mail: mark.mcentee@sydney.edu.au [Discipline of Medical Radiation Sciences, University of Sydney, Lidcombe, New South Wales (Australia)

    2014-09-15

    Digital technology has wider exposure latitude and post-processing algorithms which can mask the evidence of underexposure and overexposure. Underexposure produces noisy, grainy images which can impede diagnosis and overexposure results in a greater radiation dose to the patient. These exposure errors can result from inaccurate adjustment of exposure factors in response to changes in patient thickness. This study aims to identify all published radiographic exposure adaptation systems which have been, or are being, used in general radiography and discuss their applicability to digital systems. Studies in EMBASE, MEDLINE, CINAHL and SCOPUS were systematically reviewed. Some of the search terms used were exposure adaptation, exposure selection, exposure technique, 25% rule, 15% rule, DuPont™ Bit System and radiography. A manual journal-specific search was also conducted in The Radiographer and Radiologic Technology. Studies were included if they demonstrated a system of altering exposure factors to compensate for variations in patients for general radiography. Studies were excluded if they focused on finding optimal exposures for an ‘average’ patient or focused on the relationship between exposure factors and dose. The database search uncovered 11 articles and the journal-specific search uncovered 13 articles discussing systems of exposure adaptation. They can be categorised as simple one-step guidelines, comprehensive charts and computer programs. Only two papers assessed the efficacy of exposure adjustment systems. No literature compares the efficacy of exposure adaptations system for film/screen radiography with digital radiography technology nor is there literature on a digital specific exposure adaptation system.

  20. Patient-based radiographic exposure factor selection: a systematic review

    International Nuclear Information System (INIS)

    Ching, William; Robinson, John; McEntee, Mark

    2014-01-01

    Digital technology has wider exposure latitude and post-processing algorithms which can mask the evidence of underexposure and overexposure. Underexposure produces noisy, grainy images which can impede diagnosis and overexposure results in a greater radiation dose to the patient. These exposure errors can result from inaccurate adjustment of exposure factors in response to changes in patient thickness. This study aims to identify all published radiographic exposure adaptation systems which have been, or are being, used in general radiography and discuss their applicability to digital systems. Studies in EMBASE, MEDLINE, CINAHL and SCOPUS were systematically reviewed. Some of the search terms used were exposure adaptation, exposure selection, exposure technique, 25% rule, 15% rule, DuPont™ Bit System and radiography. A manual journal-specific search was also conducted in The Radiographer and Radiologic Technology. Studies were included if they demonstrated a system of altering exposure factors to compensate for variations in patients for general radiography. Studies were excluded if they focused on finding optimal exposures for an ‘average’ patient or focused on the relationship between exposure factors and dose. The database search uncovered 11 articles and the journal-specific search uncovered 13 articles discussing systems of exposure adaptation. They can be categorised as simple one-step guidelines, comprehensive charts and computer programs. Only two papers assessed the efficacy of exposure adjustment systems. No literature compares the efficacy of exposure adaptations system for film/screen radiography with digital radiography technology nor is there literature on a digital specific exposure adaptation system

  1. Prenatal exposure to gamma/neutron irradiation: Sensorimotor alterations and paradoxical effects on learning

    International Nuclear Information System (INIS)

    Di Cicco, D.; Antal, S.; Ammassari-Teule, M.

    1991-01-01

    The effects of prenatal exposure on gamma/neutron radiations (0.5 Gy at about the 18th day of fetal life) were studied in a hybrid strain of mice (DBA/Cne males x C57BL/Cne females). During ontogeny, measurements of sensorimotor reflexes revealed in prenatally irradiated mice (1) a delay in sensorial development, (2) deficits in tests involving body motor control, and (3) a reduction of both motility and locomotor activity scores. In adulthood, the behaviour of prenatally irradiated and control mice was examined in the open field test and in reactivity to novelty. Moreover, their learning performance was compared in several situations. The results show that, in the open field test, only rearings were more frequent in irradiated mice. In the presence of a novel object, significant sex x treatment interactions were observed since ambulation and leaning against the novel object increased in irradiated females but decreased in irradiated males. Finally, when submitted to different learning tasks, irradiated mice were impaired in the radial maze, but paradoxically exhibited higher avoidance scores than control mice, possibly because of their low pain thresholds. Taken together, these observations indicate that late prenatal gamma/neutron irradiation induces long lasting alterations at the sensorimotor level which, in turn, can influence learning abilities of adult mice

  2. Effect of irradiation and exposure to nitrogen on the mortality of adults. Tribolium confusum J. du V

    International Nuclear Information System (INIS)

    Buscarlet, L.A.; Aminian, B.; Bali, C.

    1986-09-01

    For insect control irradiation can be improved by combination with other methods in order to limit the dose and hence to preserve the sensory qualities of some foods like fresh fruits, or to kill more rapidly the adult stage for avoiding the risk that a shipment be rejected because of the presence of living insects. The effect of irradiation with long exposure to inert gaz has not been reported yet. This study presents preliminary results on Tribolium confusum. Irradiation alone from 120 to 1000 Gy killed 100% of adults T. confusum in 12 to 15 days. At 60 Gy 10% insects were living after 28 days and at 40 Gy no mortality was observed. Mortality of adults T. confusum observed 10 days after exposure to nitrogen increased with the exposure time. 100 % mortality was reached for 17 hours exposure. When insects were exposed to nitrogen before or after irradiation synergic effects were observed. The greatest efficiency was obtained when insects were irradiated at 600 Gy after 9 hr exposure. When insects were exposed to nitrogen during irradiation the protective effectt of a short exposure (1/2 hr) was observed only for low doses (< 60 Gy). For a long exposure (9 hr) early irradiation at 600 Gy was more efficient than late irradiation

  3. Exploring Global Exposure Factors Resources URLs

    Data.gov (United States)

    U.S. Environmental Protection Agency — The dataset is a compilation of hyperlinks (URLs) for resources (databases, compendia, published articles, etc.) useful for exposure assessment specific to consumer...

  4. Investigation of the combined effect of neutron irradiation and electron beam exposure on pure tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Van Renterghem, W., E-mail: wvrenter@sckcen.be; Uytdenhouwen, I., E-mail: iuytdenh@sckcen.be

    2016-08-15

    Pure tungsten samples were neutron irradiated in the BR2 reactor of SCK·CEN to fluences of 1.47 × 10{sup 20} n/cm{sup 2} and 4.74 × 10{sup 20} n/cm{sup 2} at 300 °C under Helium atmosphere and exposed to the electron beam of the Judith 1 installation The effect of these treatments on the defect structure was studied with transmission electron microscopy. In the irradiated samples the defect structure in the bulk is compared to the structure at the surface. The neutron irradiation created a large amount of a/2‹111› type dislocation loops forming dislocation rafts. The loop density increased from 8.5 × 10{sup 21}/m³ to 9 × 10{sup 22}/m³ with increasing dose, while the loop size decreased from 5.2 nm to 3.5 nm. The electron beam exposure induced significant annealing of the defects and almost all of the dislocation loops were removed. The number of line dislocations in that area increased as a result of the thermal stresses from the thermal shock. - Highlights: • Neutron irradiated and electron beam exposed tungsten samples were studied with transmission electron microscopy. • Neutron irradiation creates dislocation loops and rafts, while voids are created at higher irradiation dose. • No precipitates of transmutation products were found under these low dose irradiation conditions. • Electron beam exposure annihilates the dislocation loops and rafts.

  5. Aggregation patterns of fetal rat brain cells following exposure to X-irradiation

    International Nuclear Information System (INIS)

    Shoji, R.; Suzuki, K.; Lee, I.P.

    1980-01-01

    In our search for a simplified in vitro test system to assess the teratogenic effects of physical factors, we studied the effects of total maternal body X-irradiation on aggregation patterns of enzymatically isolated fetal rat brain cells and on ultrastructural aggregate changes. The fetal brain cells were derived from day 14 gestation fetuses of pregnant Sprague-Dawley (CD strain) rats exposed to X-irradiation (25 - 200 R) one hour prior to sacrifice. Notable changes in the cell aggregates following X-irradiation included a reduction in cell aggregate size and an increase in number. The frequency of cell aggregates was higher in the treated than in the control group, and the mean diameter of cell aggregates was inversely related to increasing X-irradiation doses. Transmission electron microscopy revealed in isolated cells features of degenerative process which were similar to those found in intact fetal brain lesions caused by maternal X-irradiation. Furthermore, scanning electron microscopy revealed that inhibition of cell aggregation following X-irradiation could probably be attributed to inhibition of membrane filopodia development and a consequent failure of cell aggregates to fuse into a greater cell aggregate mass. These results suggest that the membrane factors which influence cell aggregation may be a useful parameter to assess early effects of X-irradiation-induced brain deformity. Presently, the cell aggregation culture system is being further evaluated as a short term test system for environmental teratogens

  6. Structural transformation of CsI thin film photocathodes under exposure to air and UV irradiation

    CERN Document Server

    Tremsin, A S; Siegmund, O H W

    2000-01-01

    Transmission electron microscopy has been employed to study the structure of polycrystalline CsI thin films and its transformation under exposure to humid air and UV irradiation. The catastrophic degradation of CsI thin film photocathode performance is shown to be associated with the film dissolving followed by its re-crystallization. This results in the formation of large lumps of CsI crystal on the substrate surface, so that the film becomes discontinuous and its performance as a photocathode is permanently degraded. No change in the surface morphology and the film crystalline structure was observed after the samples were UV irradiated.

  7. Affecting Factors of Secondhand Smoke Exposure in Korea: Focused on Different Exposure Locations.

    Science.gov (United States)

    Sun, Li Yuan; Cheong, Hae Kwan; Lee, Eun Whan; Kang, Kyeong Jin; Park, Jae Hyun

    2016-09-01

    Exposure to secondhand smoke (SHS) not only can cause serious illness, but is also an economic and social burden. Contextual and individual factors of non-smoker exposure to SHS depend on location. However, studies focusing on this subject are lacking. In this study, we described and compared the factors related to SHS exposure according to location in Korea. Regarding individual factors related to SHS exposure, a common individual variable model and location-specific variable model was used to evaluate SHS exposure at home/work/public locations based on sex. In common individual variables, such as age, and smoking status showed different relationships with SHS exposure in different locations. Among home-related variables, housing type and family with a single father and unmarried children showed the strongest positive relationships with SHS exposure in both males and females. In the workplace, service and sales workers, blue-collar workers, and manual laborers showed the strongest positive association with SHS exposure in males and females. For multilevel analysis in public places, only SHS exposure in females was positively related with cancer screening rate. Exposure to SHS in public places showed a positive relationship with drinking rate and single-parent family in males and females. The problem of SHS embodies social policies and interactions between individuals and social contextual factors. Policy makers should consider the contextual factors of specific locations and regional and individual context, along with differences between males and females, to develop effective strategies for reducing SHS exposure.

  8. Lung Irradiation Increases Mortality After Influenza A Virus Challenge Occurring Late After Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Manning, Casey M. [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Johnston, Carl J. [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Department of Pediatrics, University of Rochester Medical Center, Rochester, New York (United States); Reed, Christina K. [Department of Pediatrics, University of Rochester Medical Center, Rochester, New York (United States); Lawrence, B. Paige [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York (United States); Williams, Jacqueline P. [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Finkelstein, Jacob N., E-mail: Jacob_Finkelstein@urmc.rochester.edu [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Department of Pediatrics, University of Rochester Medical Center, Rochester, New York (United States); Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States)

    2013-05-01

    Purpose: To address whether irradiation-induced changes in the lung environment alter responses to a viral challenge delivered late after exposure but before the appearance of late lung radiation injury. Methods and Materials: C57BL/6J mice received either lung alone or combined lung and whole-body irradiation (0-15 Gy). At 10 weeks after irradiation, animals were infected with 120 HAU influenza virus strain A/HKx31. Innate and adaptive immune cell recruitment was determined using flow cytometry. Cytokine and chemokine production and protein leakage into the lung after infection were assessed. Results: Prior irradiation led to a dose-dependent failure to regain body weight after infection and exacerbated mortality, but it did not affect virus-specific immune responses or virus clearance. Surviving irradiated animals displayed a persistent increase in total protein in bronchoalveolar lavage fluid and edema. Conclusions: Lung irradiation increased susceptibility to death after infection with influenza virus and impaired the ability to complete recovery. This altered response does not seem to be due to a radiation effect on the immune response, but it may possibly be an effect on epithelial repair.

  9. 75 FR 5317 - Exposure Factors Handbook: 2009 Update

    Science.gov (United States)

    2010-02-02

    ... chemicals. These factors include: Drinking water consumption; mouthing behavior; soil ingestion rates... document solely for the purpose of pre- dissemination peer review under applicable information quality... various factors used in assessing human exposure. This Handbook is aimed at exposure assessors inside the...

  10. Calculation of dose-rate conversion factors for external exposure to photons and electrons

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1978-01-01

    Methods are presented for the calculation of dose-rate conversion factors for external exposure to photon and electron radiation from radioactive decay. A dose-rate conversion factor is defined as the dose-equivalent rate per unit radionuclide concentration. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each radiation type and exposure mode, dose-rate conversion factors are derived for tissue-equivalent material at the body surface of an exposed individual. In addition, photon dose-rate conversion factors are estimated for 22 body organs. The calculations are based on the assumption that the exposure medium is infinite in extent and that the radionuclide concentration is uniform. The dose-rate conversion factors for immersion in contaminated air and water then follow from the requirement that all of the energy emitted in the radioactive decay is absorbed in the infinite medium. Dose-rate conversion factors for ground-surface exposure are calculated at a reference location above a smooth, infinite plane using the point-kernel integration method and known specific absorbed fractions for photons and electrons in air

  11. Regulation of DNA replication in irradiated cells by trans-acting factors

    International Nuclear Information System (INIS)

    Wang, Y.; Huq, M.S.; Cheng, X.; Iliakis, G.

    1995-01-01

    We compared DNA replication activity in cytoplasmic extracts prepared from irradiated and nonirradiated HeLa cells using a simian virus 40 (SV40)-based in vitro replication assay. The assay measures semi-conservative DNA replication in a plasmid carrying the SV40 origin of replication and requires SV40 T antigen as the sole noncellular protein. The plasmid DNA used in the replication reaction is never exposed to radiation. We find that replication of plasmid DNA is significantly reduced when cytoplasmic extracts from irradiated cells are used. Since plasmid replication proceeds to completion in extracts from irradiated cells, the observed reduction in the overall replication activity is probably due to a reduction in the efficiency of initiation events. The degree of inhibition of DNA replication after exposure to 10, 30 and 50 Gy X rays as measured in vitro using this assay is similar to that measured in intact cells immediately before processing for extract preparation. These observations are compatible with the induction or activation by ionizing radiation of a factor(s) that inhibits in trans DNA replication. The results contribute to our understanding of the mechanism(s) developed by the cells to regulate DNA replication when exposed to clastogenic agents. Such processes may be of significance in the restoration of DNA integrity, and may define yet another checkpoint operating during S at the level of clusters of replicons. 26 refs., 4 figs

  12. Time-activity relationships to VOC personal exposure factors

    Science.gov (United States)

    Edwards, Rufus D.; Schweizer, Christian; Llacqua, Vito; Lai, Hak Kan; Jantunen, Matti; Bayer-Oglesby, Lucy; Künzli, Nino

    Social and demographic factors have been found to play a significant role in differences between time-activity patterns of population subgroups. Since time-activity patterns largely influence personal exposure to compounds as individuals move across microenvironments, exposure subgroups within the population may be defined by factors that influence daily activity patterns. Socio-demographic and environmental factors that define time-activity subgroups also define quantifiable differences in VOC personal exposures to different sources and individual compounds in the Expolis study. Significant differences in exposures to traffic-related compounds ethylbenzene, m- and p-xylene and o-xylene were observed in relation to gender, number of children and living alone. Categorization of exposures further indicated time exposed to traffic at work and time in a car as important determinants. Increased exposures to decane, nonane and undecane were observed for males, housewives and self-employed. Categorization of exposures indicated exposure subgroups related to workshop use and living downtown. Higher exposures to 3-carene and α-pinene commonly found in household cleaning products and fragrances were associated with more children, while exposures to traffic compounds ethylbenzene, m- and p-xylene and o-xylene were reduced with more children. Considerable unexplained variation remained in categorization of exposures associated with home product use and fragrances, due to individual behavior and product choice. More targeted data collection methods in VOC exposure studies for these sources should be used. Living alone was associated with decreased exposures to 2-methyl-1-propanol and 1-butanol, and traffic-related compounds. Identification of these subgroups may help to reduce the large amount of unexplained variation in VOC exposure studies. Further they may help in assessing impacts of urban planning that result in changes in behavior of individuals, resulting in shifts in

  13. Factors affecting ultraviolet-A photon emission from β-irradiated human keratinocyte cells.

    Science.gov (United States)

    Le, M; Mothersill, C E; Seymour, C B; Ahmad, S B; Armstrong, A; Rainbow, A J; McNeill, F E

    2015-08-21

    The luminescence intensity of 340±5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to (90)Y β-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from β-irradiated cells. Exposure of 1 x 10(4) cells/5 mL to 703 μCi resulted in maximum UVA photoemission at 44.8 x 10(3)±2.5 x 10(3) counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for (90)Y activities 14 to 703 μCi where a positive relationship between photoemission and (90)Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1 x 10(4) cells/5 mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low β activities (⩽400 μCi). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

  14. A study on mice exposure dose for low-dose gamma-irradiation using glass dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Sung Jin; Kim, Hyo Jin; Kim, Hyun; Jeong, Dong Hyeok; Son, Tae Gen; Kim, Jung Ki; Yang, Kwang Mo; Kang, Yeong Rok [Research Center, Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Nam, Sang Hee [Dept. of Biomedical Engineering, Inje University, Gimhae (Korea, Republic of)

    2015-12-15

    The low dose radiation is done for a long period, thus researchers have to know the exact dose distribution for the irradiated mouse. This research has been conducted in order to find out methods in transmitting an exact dose to mouse in a mouse irradiation experiment carried out using {sup 137}C{sub s} irradiation equipment installed in the DIRAMS (Dongnam Institution of Radiological and Medical Sciences) research center. We developed a single mouse housing cage and shelf with adjustable geometric factors such as distance and angle from collimator. The measurement of irradiated dose showed a maximal 42% difference of absorbed dose from the desired dose in the conventional irradiation system, whereas only 6% difference of the absorbed dose was measured in the self-developed mouse apartment system. In addition, multi mice housing showed much difference of the absorbed dose in between head and body, compared to single mouse housing in the conventional irradiation system. This research may allow further research about biological effect assessment for the low dose irradiation using the self-developed mouse apartment to provide more exact doses which it tries to transmit, and to have more reliability for the biological analysis results.

  15. Evaluation of skin exposure of patients and the irradiation field dimensions in dental radiography

    International Nuclear Information System (INIS)

    Khoury, H.J.; Hazin, C.A.; Andrade Lima, F.R.; Lopes Filho, F.J.

    1991-01-01

    This work aimed to estimate the skin exposure to patients in dental radiography, as well as, evaluate the magnitude of the skin area irradiated during a typical radiographic procedure. The study was based in a preliminary survey of dental X-ray equipments installed in the metropolitan region of Recife. The results showed that in 90% of the equipments surveyed the estimated patient skin exposure was above the recommended value of 500 mR. For X-ray beam diameters, the results showed values ranging from 4.5 to 11.5 cm, which do not agree with those set up by either national or international radiation protection organizations. (author)

  16. Reconstruction of exposures to the public from a cobalt-60 irradiator facility

    International Nuclear Information System (INIS)

    Chapman, T.E.; Scherpelz, R.I.

    1992-01-01

    A study was performed for the US Department of Energy (DOE) to assess the radiation exposure received by the public from the operation of a cobalt-60 irradiator facility. Located south of Davis, California, at the former Laboratory for Energy-Related Health Research, the facility was an indoor-outdoor gamma irradiator operated for the DOE by the University of California, Davis. From 1970 to 1985, outdoor radiation exposure experiments conducted at the facility resulted in environmental radiation doses of 80 to 120 mSv per year along the facility's perimeter fence. Comprehensive environmental monitoring was not performed in the adjacent, uncontrolled areas and personnel who occupied these areas were not routinely monitored for radiation exposure. Because of incomplete environmental monitoring data, computer modeling was required to reconstruct the environmental dose rates present when the facility was in operation. Personnel occupancy times for the adjacent areas were determined from population statistics, historical records, and personal interviews. The potential dose equivalents calculated for the individuals who lived or worked in neighboring areas ranged from 0.02 to 3.6 mSv per year. These exposures, some of which exceed the current DOE standard of 1 mSv/y, were less than the DOE regulatory limit of 5 mSv/y for exposure to the public that was in effect when the facility was in operation

  17. Exposure to psychosocial work factors in 31 European countries.

    Science.gov (United States)

    Niedhammer, I; Sultan-Taïeb, H; Chastang, J-F; Vermeylen, G; Parent-Thirion, A

    2012-04-01

    Although psychosocial work factors are recognized as major occupational risk factors, little information is available regarding the prevalence of exposure to these factors and the differences in exposure between countries. To explore the differences in various psychosocial work exposures between 31 European countries. The study was based on a sample of 14,881 male and 14,799 female workers from the 2005 European Working Conditions Survey. Eighteen psychosocial work factors were studied: low decision latitude (skill discretion and decision authority), high psychological demands, job strain, low social support, iso-strain, physical violence, sexual harassment, bullying, discrimination, work-family imbalance, long working hours, high effort, job insecurity, low job promotion, low reward and effort-reward imbalance. Covariates were age, number of workers in household, occupation, economic activity, self-employed/employee, public/private sector and part/full time work. Statistical analysis was performed using multilevel logistic regression analysis. Significant differences in all psychosocial work factors were observed between countries. The rank of the countries varied according to the exposure considered. However, some countries, especially Denmark, Netherlands and Norway, displayed a significantly lower prevalence of exposure to four factors or more, while some Southern and Eastern countries, especially Czech Republic, Greece, Lithuania and Turkey, had a higher prevalence. Differences in psychosocial work exposures were found between countries. This study is the first to compare a large set of psychosocial work exposures between 31 European countries. These findings may be useful to guide prevention policies at European level.

  18. Chronic irradiation as an ecological factor affecting genetic population structure

    International Nuclear Information System (INIS)

    Kal'chenko, V.A.; Kalabushkin, B.A.; Rubanovich, A.V.

    1991-01-01

    Genetic structure of two Centaurea scabiosa L. populations was studied by frequency distribution of leucine aminopeptidase (LAP) locus genotypes. The experimental population has been growing under conditions of chronic irradiation, with the dose per generation amounting to 1.2 to 25.5 Gy. In it, mutational variants are observed with a frequency of 5.4.10(-3)-4.5.10(-2) per generation (as compared to control population frequency at 5.4.10(-4)). Indexes for heterozygosity, mean number of genotypes, and effective number of alleles were higher in the experimental population. Segregation analysis revealed no differences in viability in the control population, and all genotypic combinations were found to be nearly neutral. In the experimental population, however, significant differences in relative viability of the genotypes were disclosed. The relative viability of heterozygotes for mutant allele C' was nearly maximum, while heterozygotes for other mutant alleles showed minimum viability. We reach the conclusion that the differences in genetic structure of the populations under investigation can be explained by the chronic irradiation factor that brought out differences in adaptability of both normal and mutant genotypes. The suggestion is that intra-locus interactions of the C' allele with normal alleles determine plant resistance to a wide range of unfavorable environmental conditions

  19. Acute myeloid leukemia induction in CBA/H mice by irradiation with fission neutrons as a function of exposure rate

    International Nuclear Information System (INIS)

    Huiskamp, R.

    1991-01-01

    Radiation-induced acute myeloid leukemia (AML) in male CBA/H mice was used as a model for investigation of the effect of reduced fast fission neutron exposure rates on radiation-induced carcinogenesis. Groups of about 90 male CBA/H mice were irradiated or sham-irradiated at the age of 15-20 weeks. The animals were exposed to 400 mGy fast fission neutrons at exposure rates of 2, 10 or 100 mGy/min. The investigation clearly showed that reducing the exposure rate of high-LET fast fission neutrons had no influence on the incidence of AML or on the survival of the irradiated mice. In contrast, a higher incidence of lymphosarcomas was observed in mice irradiated with higher exposure rates. (orig./MG)

  20. Acute myeloid leukemia induction in CBA/H mice by irradiation with fission neutrons as a function of exposure rate

    Energy Technology Data Exchange (ETDEWEB)

    Huiskamp, R [Stichting Energieonderzoek Centrum Nederland, Petten (Netherlands). Radiobiology and Radio-Ecology Unit

    1991-06-01

    Radiation-induced acute myeloid leukemia (AML) in male CBA/H mice was used as a model for investigation of the effect of reduced fast fission neutron exposure rates on radiation-induced carcinogenesis. Groups of about 90 male CBA/H mice were irradiated or sham-irradiated at the age of 15-20 weeks. The animals were exposed to 400 mGy fast fission neutrons at exposure rates of 2, 10 or 100 mGy/min. The investigation clearly showed that reducing the exposure rate of high-LET fast fission neutrons had no influence on the incidence of AML or on the survival of the irradiated mice. In contrast, a higher incidence of lymphosarcomas was observed in mice irradiated with higher exposure rates. (orig./MG).

  1. Increased mitochondrial mass in cells with functionally compromised mitochondria after exposure to both direct gamma radiation and bystander factors.

    LENUS (Irish Health Repository)

    Nugent, Sharon M E

    2007-07-01

    The bystander effect describes radiation-like damage in unirradiated cells either in the vicinity of irradiated cells or exposed to medium from irradiated cells. This study aimed to further characterize the poorly understood mitochondrial response to both direct irradiation and bystander factor(s) in human keratinocytes (HPV-G) and Chinese hamster ovarian cells (CHO-K1). Oxygen consumption rates were determined during periods of state 4, state 3 and uncoupled respiration. Mitochondrial mass was determined using MitoTracker FM. CHO-K1 cells showed significantly reduced oxygen consumption rates 4 h after exposure to 5 Gy direct radiation and irradiated cell conditioned medium (ICCM) and an apparent recovery 12-24 h later. The apparent recovery was likely due to the substantial increase in mitochondrial mass observed in these cells as soon as 4 h after exposure. HPV-G cells, on the other hand, showed a sustained increase in oxygen consumption rates after ICCM exposure and a transient increase 4 h after exposure to 5 Gy direct radiation. A significant increase in mitochondrial mass per HPV-G cell was observed after exposure to both direct radiation and ICCM. These findings are indicative of a stress response to mitochondrial dysfunction that increases the number of mitochondria per cell.

  2. Military-Specific Exposure Factors Study

    National Research Council Canada - National Science Library

    Lurker, Peter

    1998-01-01

    ...) provides many factors needed in the assessment of human health risk that were derived from general population studies or studies involving relatively small groups that may not be representative of military populations...

  3. The effect of low exposure-rate gamma irradiation on T and B lymphocyte function in the mouse

    International Nuclear Information System (INIS)

    McDermott, C.E.; Gengozian, N.

    1980-01-01

    The effect of chronic irradiation on T and B cell numbers and function was studied in mice. Cobalt 60 gamma radiation at 6 R/hour reduced the numbers of anti-SRBC PFC in the spleen, with minimal levels recorded after total exposures of 1000 to 2000 R. Recovery was incomplete after 1000 R, reaching only 40 to 50 per cent of normal in four months and remaining at that level for the animal's lifetime. The long-term deficiency in PFC formation was not due to a quantitative lack of T or B cells since normal cell numbers were observed in the spleen 60 to 144 days after 1000 R. Adoptive transfer studies with combinations of bone marrow and thymus cells, or of splenic T and B cells, from normal and irradiated mice, revealed functional defects in both cell compartments during the first two months. Normal and near normal function of T and B cells occurred 100 days postirradiation, a time when the splenic in vitro response was still only 50 per cent of the controls. The latter observation suggests that the microenvironment of the chronically irradiated spleen alters factors regulating T and B cell interactions in response to a T-dependent antigen. (author)

  4. Comparison of higher irradiance and black panel temperature UV backsheet exposures to field performance

    Science.gov (United States)

    Felder, Thomas C.; Gambogi, William J.; Phillips, Nancy; MacMaster, Steven W.; Yu, Bao-Ling; Trout, T. John

    2017-08-01

    The need for faster PV qualification tests that more accurately match field observations is leading to tests with higher acceleration levels, and validating the new tests through comparison to field data is an important step. We have tested and compared a wide panel of backsheets according to a proposed new backsheet UV exposure qualification standard from the International Electrotechnical Commission (IEC). Weathering Technical Standard IEC 62788-7-2 specifies higher irradiance and higher black panel temperature UV Xenon exposures. We tested PVF, PVDF, PET, PA and FEVEbased backsheets in glass laminates and simple backsheet coupons in UV exposure condition A3 (0.8W/sqmnm@340nm and 90° C BPT) We find mild yellowing with no mechanical loss in the original lower intensity ASTM G155 0.55 W/sqm-nm 70C BPT exposure condition. The new A3 exposures creates mechanical loss in sensitive backsheets, with no effect on known durable backsheets. Results from the new exposure are closer to field mechanical loss data.

  5. Factors affecting outdoor exposure in winter: population-based study

    Science.gov (United States)

    Mäkinen, Tiina M.; Raatikka, Veli-Pekka; Rytkönen, Mika; Jokelainen, Jari; Rintamäki, Hannu; Ruuhela, Reija; Näyhä, Simo; Hassi, Juhani

    2006-09-01

    The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study ( n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women.

  6. Programme for reducing the risk factors due to prenatal exposure

    International Nuclear Information System (INIS)

    Arranz, L.; Ferrer, N.; Sastre, J.M.

    2001-01-01

    When a patient is not aware of her pregnancy, the foetus/embryo may be inadvertently irradiated during a diagnostic exploration or therapeutic intervention. The radiosensitivity of the foetus/embryo changes during the different periods of gestation. For this reason there are different risk factors for each moment at which the patient may suffer irradiation. In the past 7 years, the Department of Radiophysics and Radiation Protection has been consulted 75 times for this reason, to evaluate the dose received in the uterus. Since the establishment of a programme to avoid inadvertent irradiation of the foetus/embryo, these consultations have been reduced. This programme is based on informing the patients and on training the medical staff. (author)

  7. Factors Associated with Younger Adolescents’ Exposure to Online Alcohol Advertising

    Science.gov (United States)

    D’Amico, Elizabeth J.; Martino, Steven C.; Collins, Rebecca L.; Shadel, William G.; Tolpadi, Anagha; Kovalchik, Stephanie; Becker, Kirsten M.

    2016-01-01

    Little is known about the extent and nature of youth exposure to online alcohol advertising, or factors that may be associated with exposure. The current study recruited middle school students who completed a paper survey and then logged each alcohol advertisement that they encountered over a two-week period using cell phones as part of an ecological momentary assessment (EMA) design. We examined the percentage of youth who reported exposure to online alcohol advertising in the past two weeks, average weekly rate of exposure, types of online alcohol advertisements youth reported seeing, and factors that increased youths’ risk of exposure to online alcohol advertising. Analyses are based on 485 participants (47% female; 25% Hispanic, 25% white, 27% black; 6% Asian, 16% other). Youth logged exposures to a total of 3,966 (16,018 weighted for under-reporting) alcohol advertisements across the monitoring period; 154 (568 weighted) or 3.6% were online ads. Seventeen percent of youth reported seeing any online alcohol ad; the majority of online ads seen were video commercials (44.8%) and banner/side ads (26.6%). Factors associated with greater ad exposure were being older, rebellious, and Black race; greater parental monitoring and more hours spent on social media were associated with less exposure. Findings provide important information about adolescents’ exposure to online alcohol advertising and what might contribute to a greater likelihood of exposure. Given that online ad exposure is linked to drinking behavior, prevention programming for younger adolescents should continue to address this issue to help youth make healthy choices regarding alcohol use. PMID:27819430

  8. Factors associated with younger adolescents' exposure to online alcohol advertising.

    Science.gov (United States)

    D'Amico, Elizabeth J; Martino, Steven C; Collins, Rebecca L; Shadel, William G; Tolpadi, Anagha; Kovalchik, Stephanie; Becker, Kirsten M

    2017-03-01

    Little is known about the extent and nature of youth exposure to online alcohol advertising, or factors that may be associated with exposure. The current study recruited middle school students who completed a paper survey and then logged each alcohol advertisement that they encountered over a 2-week period using cell phones as part of an ecological momentary assessment design. We examined the percentage of youth who reported exposure to online alcohol advertising in the past 2 weeks, average weekly rate of exposure, types of online alcohol advertisements youth reported seeing, and factors that increased youths' risk of exposure to online alcohol advertising. Analyses are based on 485 participants (47% female; 25% Hispanic, 25% White, 27% Black; 6% Asian, 16% other). Youth logged exposures to a total of 3,966 (16,018 weighted for underreporting) alcohol advertisements across the monitoring period; 154 (568 weighted) or 3.6% were online ads. Seventeen percent of youth reported seeing any online alcohol ad; the majority of online ads seen were video commercials (44.8%) and banner/side ads (26.6%). Factors associated with greater ad exposure were being older, rebellious, and Black race; greater parental monitoring and more hours spent on social media were associated with less exposure. Findings provide important information about adolescents' exposure to online alcohol advertising and what might contribute to a greater likelihood of exposure. Given that online ad exposure is linked to drinking behavior, prevention programming for younger adolescents should continue to address this issue to help youth make healthy choices regarding alcohol use. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Bone regeneration after different lengths of exposure to laser irradiation. [Rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Strigina, L P

    1976-01-01

    Rabbits in which a portion of the tibia was excised and replaced with preserved bone were locally irradiated by an LG-75 laser (25 mv) for 30 seconds, 1, 2, 5, and 10 minutes a day for a month. Histological examination of sections showed an acceleration of the inflammatory reaction and more rapid maturation of periosteal callus in experimental animals compared to controls. Cartilage appeared on day 9 instead of 15. The proliferation of histiogenic cells and their differentiation into fibroblasts and osteoblasts were more vigorous than in the control. The effects of irradiation on osteosynthesis were directly dependent on the duration of exposure. The development of the inflammatory reaction and resorption of the graft were most pronounced in the animals exposed for 10 minutes daily.

  10. UV-B radiation and photosynthetic irradiance acclimate eggplant for outdoor exposure

    International Nuclear Information System (INIS)

    Latimer, J.G.; Mitchell, G.A.

    1987-01-01

    Treatment of greenhouse-grown eggplant (Solanum melongena L. var. esculentum Nees. 'Burpee's Black Beauty') seedlings with supplemental photosynthetically active radiation from cool-white fluorescent lamps increased growth of plants subsequently transferred outdoors relative to growth of plants that received no supplemental radiation or were shaded to 45% of solar irradiation in the greenhouse before transfer outdoors. Eggplant seedlings transferred outdoors were placed under plastic tarps either to provide relative protection from solar ultraviolet-B (UV-B) radiation (280-315 nm) using Mylar film or to allow exposure to UV-B using cellulose acetate. Protection of seedlings from UV-B radiation resulted in greater leaf expansion than for UV-B-exposed seedlings, but no change in leaf or shoot dry weight occurred after 9 days of treatment. Specific leaf weight increased in response to UV-B exposure outdoors. Exposure of eggplant to UV-B radiation from fluorescent sunlamps in the greenhouse also decreased leaf expansion and leaf and shoot dry weight gain after 5 days of treatment. However, there were no differences in leaf or shoot dry weight relative to control plants after 12 days of UV-B treatment, indicating that UV-B treated plants had acclimated to the treatment and actually had caught up with non-UV-B-irradiated plants in terms of growth

  11. Recovery of Lemna minor after exposure to sulfadimethoxine irradiated and non-irradiated in a solar simulator.

    Science.gov (United States)

    Drobniewska, Agata; Wójcik, Dorota; Kapłan, Monika; Adomas, Barbara; Piotrowicz-Cieślak, Agnieszka; Nałęcz-Jawecki, Grzegorz

    2017-12-01

    Sulfonamides are the second most widely used group of veterinary antibiotics which are often detected in the environment. They are eliminated from freshwaters mainly through photochemical degradation. The toxicity of sulfadimethoxine (SDM) was evaluated with the use of Lemna minor before and after 1- and 4-h irradiation in a SunTest CPS+ solar simulator. Eight endpoints consisting of: number and total area of fronds, fresh weight, chlorophylls a and b, carotenoids, activity of catalase and guaiacol peroxidase, and protein content were determined. The total frond area and chlorophyll b content were the most sensitive endpoints with EC50 of 478 and 554 μg  L -1 , respectively. The activity of guaiacol peroxidase and catalase increased at SDM concentrations higher than 125 and 500 μg  L -1 , respectively. The SDM photodegradation rate for first order kinetics and the half-life were 0.259 h -1 and 2.67  h, respectively. The results show that the toxicity of irradiated solutions was caused by SDM only, and the photoproducts appeared to be either non-toxic or much less toxic to L. minor than the parent compound. To study the recovery potential of L. minor, after 7 days exposure in SDM solutions, the plants were transferred to fresh medium and incubated for the next 7 days. L. minor has the ability to regenerate, but a 7-day recovery phase is not sufficient for it to return to an optimal physiological state.

  12. Factors impacting public acceptance of medical radiation exposure

    International Nuclear Information System (INIS)

    Tsuji, Satsuki; Kanda, Reiko

    2009-01-01

    We undertook a survey to determine the public acceptance of medical radiation exposure throughout Japan, and 1,357 responses (67.9% response rate) were obtained using a two-stage systematic stratified random sampling method. The acceptance of exposure of children was generally similar to that of adults. For each of the attributes, 45-60% of the participants were accepting of exposure for cancer treatment and diagnosis, but only 30% were accepting of exposure for X-ray diagnoses of bone fractures and dental caries. In general, the presence of a child did not markedly affect women's acceptance of exposure. Factor analyses identified 3 factors influencing the acceptance of child exposure: symptomatic diseases to determine treatment, the possibility of high-risk diseases (or major organ diseases), and the association with cancer. Cluster analysis showed 4 clusters: a positive group regarding children's exposure for the diagnosis of bone fractures and dental caries (12.9% of all participants), a positive group for major organ disease and cancer (15.5%), a negative group excluding cancer (55.2%), and a positive group for all cases (16.4%). The cluster distributions revealed that mothers with 10- to 18-year-old firstborn children showed a tendency to accept the medical radiation exposure of their children in all cases. (author)

  13. Safety factors influencing the acceptance of food irradiation technology

    International Nuclear Information System (INIS)

    1989-01-01

    The International Consultative Group on Food Irradiation convened a Task Force Meeting on Public Information of Food Irradiation at the French Commissariat a l'Energie Atomique (CEA), Cadarache from 18 to 21 April 1988. A compilation of scientific papers on subjects of public interest on food irradiation was made by internationally-recognized experts. The report of the meeting and the review papers presented at the meeting are included in this publication. Refs, figs and tabs

  14. An overview of microstructural and experimental factors that affect the irradiation growth behavior of zirconium alloys

    International Nuclear Information System (INIS)

    Fidleris, V.; Tucker, R.P.; Adamson, R.B.

    1987-01-01

    This paper presents an overview of factors affecting irradiation growth of zirconium alloys. Recent data obtained from irradiation programs in EBR-II, ATR, and NRU reactors are used to illustrate the effects of various microstructural and experimental factors on the growth of Zircaloy, zirconium, and zirconium-biobium alloys irradiated to fluences up to 2 X 10 26 nm -2 (E > 1 MeV) over the temperature range 330 to 720 K. Open literature results are also used to confirm or illustrate various effects. Important factors are texture, grain boundary parameters, residual stresses, original dislocation density, microstructure evolution, temperature during irradiation, solute effects, and fluence

  15. Standardized approach for developing probabilistic exposure factor distributions

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, Randy L.; McKone, Thomas E.; Sohn, Michael D.

    2003-03-01

    The effectiveness of a probabilistic risk assessment (PRA) depends critically on the quality of input information that is available to the risk assessor and specifically on the probabilistic exposure factor distributions that are developed and used in the exposure and risk models. Deriving probabilistic distributions for model inputs can be time consuming and subjective. The absence of a standard approach for developing these distributions can result in PRAs that are inconsistent and difficult to review by regulatory agencies. We present an approach that reduces subjectivity in the distribution development process without limiting the flexibility needed to prepare relevant PRAs. The approach requires two steps. First, we analyze data pooled at a population scale to (1) identify the most robust demographic variables within the population for a given exposure factor, (2) partition the population data into subsets based on these variables, and (3) construct archetypal distributions for each subpopulation. Second, we sample from these archetypal distributions according to site- or scenario-specific conditions to simulate exposure factor values and use these values to construct the scenario-specific input distribution. It is envisaged that the archetypal distributions from step 1 will be generally applicable so risk assessors will not have to repeatedly collect and analyze raw data for each new assessment. We demonstrate the approach for two commonly used exposure factors--body weight (BW) and exposure duration (ED)--using data for the U.S. population. For these factors we provide a first set of subpopulation based archetypal distributions along with methodology for using these distributions to construct relevant scenario-specific probabilistic exposure factor distributions.

  16. Chemical composition dependence of exposure buildup factors for some polymers

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Tejbir [Department of Physics, S.D.D.I.E.T., Barwala, District Panchkula, Haryana 134 118 (India)], E-mail: tejbir.s@rediffmail.com; Kumar, Naresh [Department of Physics, Lovely Professional University, Phagwara 144 402 (India)], E-mail: naresh20dhiman@yahoo.com; Singh, Parjit S. [Department of Physics, Punjabi University, Patiala 147 002 (India)], E-mail: dr_parjit@hotmail.com

    2009-01-15

    Exposure buildup factors for some polymers such as poly-acrylo-nitrile (PAN), poly-methyl-acrylate (PMA), poly-vinyl-chloride (PVC), synthetic rubber (SR), tetra-fluro-ethylene (Teflon) have been computed using the G.P. fitting method in the energy range of 0.015-15.0 MeV, up to the penetration of 40 mean free paths (mfp). The variation of exposure buildup factors for all the selected polymers with incident photon energy at the fixed penetration depths has been studied, mainly emphasizing on chemical composition (equivalent atomic number) of the selected polymers. It has been observed that for the lower penetration depths (below 10 mfp), the exposure buildup factor decreases with the increase in equivalent atomic number of the selected polymers at all the incident photon energies. However, at the penetration depth of 10 mfp and incident photon energy above 3 MeV, the exposure buildup factor becomes almost independent of the equivalent atomic number of the selected polymers. Further, above the fixed penetration depth of 15 mfp of the selected polymers and above the incident photon energy of 3 MeV, reversal in the trend has been observed, i.e., the exposure buildup factor increases with the increase in equivalent atomic number.

  17. Chemical composition dependence of exposure buildup factors for some polymers

    International Nuclear Information System (INIS)

    Singh, Tejbir; Kumar, Naresh; Singh, Parjit S.

    2009-01-01

    Exposure buildup factors for some polymers such as poly-acrylo-nitrile (PAN), poly-methyl-acrylate (PMA), poly-vinyl-chloride (PVC), synthetic rubber (SR), tetra-fluro-ethylene (Teflon) have been computed using the G.P. fitting method in the energy range of 0.015-15.0 MeV, up to the penetration of 40 mean free paths (mfp). The variation of exposure buildup factors for all the selected polymers with incident photon energy at the fixed penetration depths has been studied, mainly emphasizing on chemical composition (equivalent atomic number) of the selected polymers. It has been observed that for the lower penetration depths (below 10 mfp), the exposure buildup factor decreases with the increase in equivalent atomic number of the selected polymers at all the incident photon energies. However, at the penetration depth of 10 mfp and incident photon energy above 3 MeV, the exposure buildup factor becomes almost independent of the equivalent atomic number of the selected polymers. Further, above the fixed penetration depth of 15 mfp of the selected polymers and above the incident photon energy of 3 MeV, reversal in the trend has been observed, i.e., the exposure buildup factor increases with the increase in equivalent atomic number

  18. Evaluation of dose exposure from irradiated samples at TRIGA PUSPATI reactor (RTP)

    International Nuclear Information System (INIS)

    Muhd Husamuddin Abdul Khalil; Julia Abdul Karim; Naim Syauqi Hamzah; Mohamad Hairie Rabir; Mohd Amin Sharifuldin Salleh

    2010-01-01

    An evaluation has been made to data of irradiated samples for the type of sample requested for activation at RTP. Sample types are grouped with percentage of total throughputs to rule out the weight percent of every respective group. The database consists of radionuclide inventory of short, intermediate and long half-life and high activity radionuclides such as Br and Au have been identified. Evaluation of gamma exposure using Micro shield has also been made to pattern the trend of gamma exposure at experimental facilities and to ensure radiological effect towards safety and health is limited per Radiation Protection (Basic Safety Standard) Regulation 1988. This analysis places an important parameter to improve the design accuracy of shielding design in assuring safety, reliability and economy. (author)

  19. Incidence and risk factors of occupational blood exposure

    DEFF Research Database (Denmark)

    Nelsing, S; Nielsen, T L; Brønnum-Hansen, Henrik

    1997-01-01

    Occupational blood exposures involves a risk of transmission of serious infections. We performed a nation-wide survey, to describe the incidence and risk factors of percutaneous (PCE) and mucocutaneous (MCE) blood exposures among hospital employed doctors in Denmark. Of 9,374 questionnaires, 6......). Only 35% adhered to the basic principles of universal precautions (UP) and non-compliance was associated with a considerably increased risk of both MCE and PCE, especially in non-surgical specialties. In conclusion, we found an unacceptably high incidence of occupational blood exposures among Danish...

  20. Energy absorption and exposure build-up factors in teeth

    International Nuclear Information System (INIS)

    Manjunatha, H.C.; Rudraswamy, B.

    2010-01-01

    Full text: Gamma and X-radiation are widely used in medical imaging and radiation therapy. The user of radioisotopes must have knowledge about how radiation interacts with matter, especially with the human body, because when photons enter the medium/body, they degrade their energy and build up in the medium, giving rise to secondary radiation which can be estimated by a factor which is called the 'build-up factor'. It is essential to study the exposure build up factor in radiation dosimetry. G.P. fitting method has been used to compute energy absorption and exposure build-up factor of teeth (enamel outer surface (EOS), enamel middle (EM), enamel dentin junction towards enamel (EDJE), enamel dentin junction towards dentin (EDJD), dentin middle (DM) and dentin inner surface (DIS)) for wide energy range (0.015 MeV-15 MeV) up to the penetration depth of 40 mean free path. The dependence of energy absorption and exposure build up factor on incident photon energy, Penetration depth and effective atomic number has also been assessed. The relative dose distribution at a distance r from the point source is also estimated. The computed exposure and absorption build-up factors are useful to estimate the gamma and Bremsstrahlung radiation dose distribution teeth which is useful in clinical dosimetry

  1. Gamma exposure rate estimation in irradiation facilities of nuclear research reactors

    International Nuclear Information System (INIS)

    Daoud, Adrian

    2009-01-01

    There are experimental situations in the nuclear field, in which dose estimations due to energy-dependent radiation fields are required. Nuclear research reactors provide such fields under normal operation or due to radioactive disintegration of fission products and structural materials activation. In such situations, it is necessary to know the exposure rate of gamma radiation the different materials under experimentation are subject to. Detectors of delayed reading are usually used for this purpose. Direct evaluation methods using portable monitors are not always possible, because in some facilities the entrance with such devices is often impracticable and also unsafe. Besides, these devices only provide information of the place where the measurement was performed, but not of temporal and spatial fluctuations the radiation fields could have. In this work a direct evaluation method was developed for the 'in-situ' gamma exposure rate for the irradiation facilities of the RA-1 reactor. This method is also applicable in any similar installation, and may be complemented by delayed evaluations without problem. On the other hand, it is well known that the residual effect of radiation modifies some properties of the organic materials used in reactors, such as density, colour, viscosity, oxidation level, among others. In such cases, a correct dosimetric evaluation enables in service estimation of material duration with preserved properties. This evaluation is for instance useful when applied to lubricating oils for the primary circuit pumps in nuclear power plants, thus minimizing waste generation. In this work the necessary elements required to estimate in-situ time and space integrated dose are also established for a gamma irradiated sample in an irradiation channel of a nuclear facility with zero neutron flux. (author)

  2. Effect of gamma irradiation on some nutritional factors of rice

    International Nuclear Information System (INIS)

    Mohamad Khan Ayob; Osman Hassan.

    1987-01-01

    The effect of gamma irradiation and types of packaging material used (namely: gunny sack, heavy duty polyethylene, woven laminated bags) on moisture content, gel viscosity and reducing sugar of rice was observed. Moisture content, gel viscosity and reducing sugar were determined by drying method, brookfield viscometer and Nelson method, respectively. The results showed that moisture and reducing sugar content were not significantly affected by types of material and irradiation doses. On the other hand gel viscosity was greatly influenced by irradiation doses and storage time. (A.J.)

  3. Exposure level of ergonomic risk factors in hotel industries

    Science.gov (United States)

    Nasrull Abdol Rahman, Mohd; Syahir Muhamad Jaffar, Mohd; Fahrul Hassan, Mohd; Zamani Ngali, Mohd; Pauline, Ong

    2017-08-01

    Ergonomic Risk Factors (ERFs) which contribute to Musculoskeletal Disorders (MSDs) among room attendants were considered as a problem or trouble since these ERFs would affect their work performance for hotel industries. The purpose of this study was to examine the exposure level of ERFs among room attendants in hotel industries. 65 of respondents were obtained from selected hotels in Peninsular Malaysia. Data were collected by direct observation via Workplace Ergonomic Risk Assessment (WERA) and Quick Exposure Checklist (QEC). There were 36 males and 29 females room attendants involved throughout the research. Most of room attendants experienced high exposure level for back, leg, forceful and vibration based on the exposure level evaluation through WERA while QEC results showed that all room attendants were found to have moderate exposure level for risk factors including back for movement use, shoulders/arms, wrists/hands and neck. All the results obtained showed that the related ERFs for MSDs were associated and essential ergonomic interventions are needed in order to eliminate risk of exposures to MSDs among room attendants in hotel industries.

  4. Stimulation of TLR7 with Gardiquimod Enhances Protection and Activation of Immune Cells from γ-Irradiation Exposure

    International Nuclear Information System (INIS)

    Yang, Young-Mi; Bang, Ji-Young; Lee, Suhl-Hyeong; Moon, Tae-Min; Jung, Yu-Jin

    2007-01-01

    Radiotherapy for cancer patients is based on the radiation-induced cell death, but high dose of radiation is able to cause break of immune system. Thus, protection of immune cells from radiation damage is required to enhance the efficiency and reduce the harmful side effects during cancer radiotherapy. Toll-like receptors (TLRs) are important not only in initiating innate immunity against microbial infection, but also inducing Th1-mediated immunity with producing cytokines and chemokines. Cell stimulation via TLRs leads to downstream activation of NF-kB and other transcription factors. Consequently, several genes encoding mediators and effector molecules of the innate as well as the adaptive immune response are transcribed. There are several previous findings that activated immune cells via TLR9 inducing pathways are resistant to chemical or radiation exposure. But it is not clear that the other TLRs also have the same abilities to protect immune cells against cellular damages including γ-irradiation. This research was performed to evaluate protective effect of immune cells from γ-irradiation through TLR-7 activation pathway

  5. Radio -Protective Role of Zinc Administration Pre-Exposure to Gamma-Irradiation in Male Albino Mice

    International Nuclear Information System (INIS)

    El-Dawy, H.A.; Aly El-Sayed, S.M.

    2004-01-01

    This study was performed to evaluate the potency of zinc chloride injected subcutaneously (30 mg/kg b.w.) in male albino mice as a radio-protective agent pre exposure to gamma-irradiation. The investigation of the radio-protective role of zinc chloride was accomplished through measuring the levels of sex hormones, and observation of the chromosomal aberrations and sperm-head abnormalities after exposure to gamma-irradiation. The average of abnormal cells with chromosomal aberration and abnormal sperm % on the 7 th and 21 th days were 32% and 40%, and 14% and 22% respectively in mice exposed to radiation alone compared to 12% and 16%, and 5% and 12% respectively in mice treated with zinc chloride pre-irradiation. Treatment of mice with zinc chloride pre-irradiation induced significant amelioration in FSH and LH hormone levels on the 7 th day only of experimentation period, and showed non-significant amelioration in testosterone level

  6. Factors influencing radiation exposure during the extracorporeal shock wave lithotripsy

    Energy Technology Data Exchange (ETDEWEB)

    Wei Chuan Chen; Ying Huei Lee; Ming Tsun Chen; Jong Khing Huang; Luke S Chang (Division of Urology, Dept. of Surgery, National Yang-Ming Medical College and Veterans General Hospital-Taipei, Taiwan (China))

    1991-01-01

    A prospective evaluation of 89 consecutive sessions of extracorporeal shock wave lithotripsy (ESWL) was undertaken to try and find the best way of minimising the amount of exposure to radiation. Forty-two patients were randomly allocated to undergo ESWL treatment by experienced surgeons (group A), and 47 to undergo the treatment by inexperienced surgeons (group B). The mean calculated entrance radiation exposure was 3.01 rads (group A: 2.64 (0.97) rads, range 1.00-4.48, group B: 3.38 (0.86) rads, range 1.11-5.75). Among factors that influenced radiation exposure, the tissue: air ratio should be borne in mind and the level of skill in controlling movement of gantry was the most important in reducing the exposure to radiation. (au).

  7. Factors influencing radiation exposure during the extracorporeal shock wave lithotripsy

    International Nuclear Information System (INIS)

    Wei Chuan Chen; Ying Huei Lee; Ming Tsun Chen; Jong Khing Huang; Luke S Chang

    1991-01-01

    A prospective evaluation of 89 consecutive sessions of extracorporeal shock wave lithotripsy (ESWL) was undertaken to try and find the best way of minimising the amount of exposure to radiation. Forty-two patients were randomly allocated to undergo ESWL treatment by experienced surgeons (group A), and 47 to undergo the treatment by inexperienced surgeons (group B). The mean calculated entrance radiation exposure was 3.01 rads (group A: 2.64 (0.97) rads, range 1.00-4.48, group B: 3.38 (0.86) rads, range 1.11-5.75). Among factors that influenced radiation exposure, the tissue: air ratio should be borne in mind and the level of skill in controlling movement of gantry was the most important in reducing the exposure to radiation. (au)

  8. REQUIREMENTS TO THE LIMITATION OF POPULATION EXPO-SURE FROM THE NATIRAL IONIZING IRRADIATION SOURCES IN INDUSTRIAL CONDITIONS

    Directory of Open Access Journals (Sweden)

    I. P. Stamat

    2010-01-01

    Full Text Available The paper presents conceptually new requirements to the limitation of population exposure from the natural ionizing irradiation sources in industrial conditions, introduced into Basic Sanitary Rules of Radiation Safety (OSPORB-99/2010. It is shown that, first of all, introduction of these requirements is aimed at the resolution of variety of previously existing serious contradictions in organization of radiation safety control and supervision for the impact of natural ionizing irradiation sources in industry.

  9. Radiography simulation based on exposure buildup factors for multilayer structures

    International Nuclear Information System (INIS)

    Marinkovic, Predrag; Pesic, Milan

    2009-01-01

    Monte Carlo techniques were usually used to study the effect of scattered photons on a radiographic X-ray image. Such approach is accurate, but computer time consuming. On the other hand, the exposure buildup factors can be used as approximate and efficient assessment to account for the scattering of X-rays. This method uses the known radiography parameters to find the resulting detector exposure due to both scattered and un-collided photons. A model for radiography simulation, based on X-ray dose buildup factor, is proposed. This model includes non-uniform attenuation in voxelized object of imaging (patient body tissue). Composition of patient body is considered as a multi-layer structure. Various empirical formulas exist for multi-layer structure calculations and they all calculate multi-layer buildup factors by combining single-layer buildup factors. The proposed model is convenient in cases when more exact techniques (like Monte Carlo) are not economical. (author)

  10. Calculating gamma dose factors for hot particle exposures

    International Nuclear Information System (INIS)

    Murphy, P.

    1990-01-01

    For hot particle exposures to the skin, the beta component of radiation delivers the majority of the dose. However, in order to fully demonstrate regulatory compliance, licenses must ordinarily provide reasonable bases for assuming that both the gamma component of the skin dose and the whole body doses are negligible. While beta dose factors are commonly available in the literature, gamma dose factors are not. This paper describes in detail a method by which gamma skin dose factors may be calculated using the Specific Gamma-ray Constant, even if the particle is not located directly on the skin. Two common hot particle exposure geometries are considered: first, a single square centimeter of skin lying at density thickness of 7 mg/cm 2 and then at 1000 mg/cm 2 . A table provides example gamma dose factors for a number of isotopes encountered at power reactors

  11. Variability and uncertainty in Swedish exposure factors for use in quantitative exposure assessments.

    Science.gov (United States)

    Filipsson, Monika; Öberg, Tomas; Bergbäck, Bo

    2011-01-01

    Information of exposure factors used in quantitative risk assessments has previously been compiled and reported for U.S. and European populations. However, due to the advancement of science and knowledge, these reports are in continuous need of updating with new data. Equally important is the change over time of many exposure factors related to both physiological characteristics and human behavior. Body weight, skin surface, time use, and dietary habits are some of the most obvious examples covered here. A wealth of data is available from literature not primarily gathered for the purpose of risk assessment. Here we review a number of key exposure factors and compare these factors between northern Europe--here represented by Sweden--and the United States. Many previous compilations of exposure factor data focus on interindividual variability and variability between sexes and age groups, while uncertainty is mainly dealt with in a qualitative way. In this article variability is assessed along with uncertainty. As estimates of central tendency and interindividual variability, mean, standard deviation, skewness, kurtosis, and multiple percentiles were calculated, while uncertainty was characterized using 95% confidence intervals for these parameters. The presented statistics are appropriate for use in deterministic analyses using point estimates for each input parameter as well as in probabilistic assessments. © 2010 Society for Risk Analysis.

  12. Effects of UV irradiation and UV/chlorine co-exposure on natural organic matter in water

    International Nuclear Information System (INIS)

    Liu, Wei; Zhang, Zaili; Yang, Xin; Xu, Yiyue; Liang, Yongmei

    2012-01-01

    The effects of co-exposure to ultraviolet (UV) irradiation (with either low- or medium-pressure UV lamps) and free chlorine (chloramine) at practical relevant conditions on changes in natural organic matter (NOM) properties were investigated using four waters. The changes were characterized using the specific disinfection by-product formation potential (SDBPFP), specific total organic halogen formation potential (STOXFP), differential UV absorbance (∆UVA), and size-exclusion chromatography (SEC). The results for exposure to UV irradiation alone and for samples with no exposure were also obtained. The SDBPFPs in all UV-irradiated NOM waters observed were higher than those of non-irradiated samples. UV irradiation led to increases in STOXFPs as a result of chlorination, but no changes, or only small decreases, from chloramination. UV irradiation alone led to positive ∆UVA spectra of the four NOM waters; co-exposure to UV and chlorine gave larger negative ∆UVA spectra than those obtained by chlorine exposure alone. No obvious changes in SEC results were observed for samples only irradiated with UV light; co-exposure gave no detectable changes in the abundances of small fractions for exposure to chlorine only. Both UV photooxidation and photocatalytic oxidation appear to affect the reactivity of the NOM toward subsequent chlorination, and the magnitude of the changes is generally greater for medium-pressure lamps than for low-pressure lamps. These results suggest that applying UV disinfection technology to a particular source may not always be disinfection by-product-problem-free, and the interactions between UV light, chlorine, and NOM may need to be considered. - Highlights: ► We discussed the effects of co-exposure to UV light and chlorine on properties of natural organic matters in waters. ► UV irradiation led to increases in SDBPFP and STOXFP of NOM waters from chlorination. ► We suggest that applying an UV disinfection technology to a particular

  13. Time factor of BSH from intravenous infusion to neutron irradiation for BNCT in patients with glioblastoma

    International Nuclear Information System (INIS)

    Kageji, T.; Nagahiro, S.; Kitamura, K.; Nakagawa, Y.; Hatanaka, H.; Haritz, D.; Grochulla, F.; Haselsberger, K.; Gabel, D.

    2000-01-01

    The present report evaluates the time factor of BSH from infusion to irradiation in patients with glioblastoma as a cooperative study in Europe and Japan. For BNCT with BSH after intravenous infusion, this work confirms that the planned neutron irradiation after intravenous BSH infusion appears to be optimal around 12-19 hours after the infusion. (author)

  14. Concept of malignant significant factor and its applicability for and occupational exposures

    International Nuclear Information System (INIS)

    Hashizume, Tadashi; Maruyama, Takashi; Tateno, Yukio

    1980-01-01

    In the medical and occupational exposures, there is a tradition to use the genetically significant dose as an index of harm to the population although it only includes the genetical effects from ionizing radiations. A similar significant dose for somatic effects such as radiation leukemogenesis and carcinogenesis should be added to the genetically significant dose in order to approach an index of total harm to the population from medical and occupational exposures. For this purpose, leukemia and malignant significant factors were determined based on the induction of malignant diseases including leukemia for the atomic bombs in Hiroshima and Nagasaki and the life expectancy of individuals subject to medical examinations or treatments as well as radiation workers, taking account of the possibility of their deaths due to other diseases or accidents during a latent period of malignant diseases. The resultant significant factors were tabulated as a function of life expectancy for their application to medical and occupational exposures. For an example, the malignant significant factor for a person having the life expectancy of 60, 40 and 20 years was about 0.87, 0.45 and 0.10, respectively. This paper will discuss the applicability of the leukemia and malignant significant factors to the risk estimation of medical and occupational exposures; namely (1) the risk estimation for an individual in the population; (2) the risk estimation for individuals in a given age group who were continuously irradiated with natural radiations or received occupational exposures; (3) the risk estimation for the pupulation in a given age distribution and (4) the risk estimation for individuals after retirement of radiation works. (author)

  15. γ-ray induced chromosome aberration in rabbit peripheral blood lymphocytes irradiated in partial and whole body and decline of aberration rate with time post-exposure

    International Nuclear Information System (INIS)

    Zhang Lianzhen; Deng Zhicheng; Wang Haiyan

    1997-01-01

    Te author presents the results of study on 60 Co γ-ray induced chromosome aberration in rabbits peripheral blood lymphocytes irradiated in partial and whole body and the aberration rate decrease with the time of post-exposure. The experiments included 5 groups, it was whole-body exposure group, partial-body exposure (abdomen and pelvic cavity) group, blood irradiation group in vitro and control group respectively. Radiation dose was 3.0 Gy delivered at rate of 0.5 Gy/min. The results show that it was no significant differences between whole body and in blood irradiation group. The chromosome aberration yield in whole body exposure group was higher than that in partial-body group and in the abdomen exposure group was higher than in that in the pelvic cavity irradiation; The chromosome aberration rate decreased with the time of post-exposure in partial and whole body by γ-ray irradiation

  16. Non-targeted and delayed effects of exposure to ionizing radiation: II. Radiation-induced genomic instability and bystander effects in vivo, clastogenic factors and transgenerational effects

    Science.gov (United States)

    Morgan, William F.

    2003-01-01

    The goal of this review is to summarize the evidence for non-targeted and delayed effects of exposure to ionizing radiation in vivo. Currently, human health risks associated with radiation exposures are based primarily on the assumption that the detrimental effects of radiation occur in irradiated cells. Over the years a number of non-targeted effects of radiation exposure in vivo have been described that challenge this concept. These include radiation-induced genomic instability, bystander effects, clastogenic factors produced in plasma from irradiated individuals that can cause chromosomal damage when cultured with nonirradiated cells, and transgenerational effects of parental irradiation that can manifest in the progeny. These effects pose new challenges to evaluating the risk(s) associated with radiation exposure and understanding radiation-induced carcinogenesis.

  17. Modulation of Radiation responses by pre-exposure to irradiated Cell conditioned medium.

    LENUS (Irish Health Repository)

    Maguire, Paula

    2007-04-01

    The aim of this study was to investigate whether exposure of HPV-G cells to irradiated cell conditioned medium (ICCM) could induce an adaptive response if the cells were subsequently challenged with a higher ICCM dose. Clonogenic survival and major steps in the cascade leading to apoptosis, such as calcium influx and loss of mitochondrial membrane potential, were examined to determine whether these events could be modified by giving a priming dose of ICCM before the challenge dose. Clonogenic survival data indicated an ICCM-induced adaptive response in HPV-G cells "primed" with 5 mGy or 0.5 Gy ICCM for 24 h and then exposed to 0.5 Gy or 5 Gy ICCM. Reactive oxygen species (ROS) were found to be involved in the bystander-induced cell death. Calcium fluxes varied in magnitude across the exposed cell population, and a significant number of the primed HPV-G cells did not respond to the challenge ICCM dose. No significant loss of mitochondrial membrane potential was observed when HPV-G cells were exposed to 0.5 Gy ICCM for 24 h followed by exposure to 5 Gy ICCM for 6 h. Exposure of HPV-G cells to 5 mGy ICCM for 24 h followed by exposure to 0.5 Gy ICCM for 18 h caused a significant increase in mitochondrial mass and a change in mitochondrial location, events associated with the perpetuation of genomic instability. This study has shown that a priming dose of ICCM has the ability to induce an adaptive response in HPV-G cells subsequently exposed to a challenge dose of ICCM.

  18. Mechanical Properties of Renewable Polymer with Thermoplastics Endurance to Ultraviolet irradiation Exposure

    Directory of Open Access Journals (Sweden)

    Salim Nurul Syamimi M.

    2016-01-01

    Full Text Available At present the disposal of waste tyre rubber (WTR has become a major waste management problem in the world. Therefore in this study, polymer blended based on Polyethylene which is Low Density Polyethylene (LDPE or High Density Polyethylene (HDPE, with Renewable Polymer (RP and waste tyre rubber (WTR is prepared via injection molding. Blended polymer such as LDPE/RP/WTR and HDPE/RP/WTR is known as LRT and HRT respectively. The preparation of polymer blend steps start with the preparation of RP. The RP is prepared by crosslinking the renewable monomer with Polymethane Polyphenyl Isocyanate (MDI at composition ratio of 1:0.5. The second steps involved by adding 10 gm of liquid RP prepared earlier on with fixed amount of LDPE and HDPE of 100 gm. Then the blended LDPE/RP or HDPE/RP namely as LR or HR respectively is further added with WTR with different percentages ratio of 5 %, 10 % and 15 %. The manually blended polymer mixture and filler is then melt mixing using injection moulding to fabricate the tensile specimen for mechanical tensile test and physical determination such as density, distribution of WTR in polymer blend and surface fracture morphology using scanning electron microscope. The samples were then exposed to UV irradiation exposure in UV Accelerated Weathering for 500, 1000, 1500, 2000, 2500 and 3000 hours to evaluate the photostability of the polymer blends. The optimum amount of WTR ratio composition is at 5 % for both LRT and HRT blends which indicate the stability of polymer blends towards UV irradiation exposure at 1000 hours.

  19. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Science.gov (United States)

    Taghinejad-Roudbaneh, M.; Ebrahimi, S. R.; Azizi, S.; Shawrang, P.

    2010-12-01

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased ( Pruminal degradation and reducing antinutritional factors of irradiated canola meal.

  20. Saffron extracts effect on processes in brain structures under exposure to x-ray irradiation of medium dose

    International Nuclear Information System (INIS)

    Rzaeva, A.

    2012-01-01

    Full text : Process of ionizing radiation on live organism is accompanied by interaction of free radicals (FR) with molecules of proteins, nucleic acids and lipids. In its turn, FR occurs subsequently by excitation and ionization of molecules. Besides all, ionizing radiation becomes the reason of accumulation in body tissues of toxic products (radio toxic) that strengthen beam effect. Endogenous antioxidatic system (EAS) of an organism plays a significant role in detoxication of redundant quantity of FR formed in cells. Ionizing radiation influences negatively to high-grade functioning of basic EAS enzymes. Besides, during radiation injuries, the level of FR increases. In case of its exhaustion and lack insertion of natural antioxidants (bioantioxidants) to organism plays a therapeutic role. Thus, in our work we used saffron extract in experiments with the purpose of studying its effect on the activity of antioxidant enzymes at radiation influence. Determination of proteins has been carried out with Lowry method. In the result of carried-out researches, it has been detected fixed dynamics of activity change of antioxidant enzymes in various brain structures of white rats within x-ray irradiation at medium dose, and joint impact of x-ray radiation of saffron extract. Under exposure to X-ray irradiation of medium dose in some brain structures decreasing of catalase activity was revealed. Tendency towards decreasing is more developed on the 3th day of irradiation. As opposed to catalase activity GPO activity was increased. Insertion of saffron extract to experimental animals (for 21 days before irradiation) conducive to prevention the decreasing of catalase activity stabilizes GPO activity and exerts an effective influence. Thereby, bioantioxidants have significant role in the regulation of processes occurred in tissues and cells under the influence of extreme factors. Antioxidant protection system of organism carries out continuous protection of organism from toxic

  1. Risk Factors for Breast Cancer, Including Occupational Exposures

    Directory of Open Access Journals (Sweden)

    Elisabete Weiderpass

    2011-03-01

    Full Text Available The knowledge on the etiology of breast cancer has advanced substantially in recent years, and several etiological factors are now firmly established. However, very few new discoveries have been made in relation to occupational risk factors. The International Agency for Research on Cancer has evaluated over 900 different exposures or agents to-date to determine whether they are carcinogenic to humans. These evaluations are published as a series of Monographs (www.iarc.fr. For breast cancer the following substances have been classified as “carcinogenic to humans” (Group 1: alcoholic beverages, exposure to diethylstilbestrol, estrogen-progestogen contraceptives, estrogen-progestogen hormone replacement therapy and exposure to X-radiation and gamma-radiation (in special populations such as atomic bomb survivors, medical patients, and in-utero exposure. Ethylene oxide is also classified as a Group 1 carcinogen, although the evidence for carcinogenicity in epidemiologic studies, and specifically for the human breast, is limited. The classification “probably carcinogenic to humans” (Group 2A includes estrogen hormone replacement therapy, tobacco smoking, and shift work involving circadian disruption, including work as a flight attendant. If the association between shift work and breast cancer, the most common female cancer, is confirmed, shift work could become the leading cause of occupational cancer in women.

  2. Dose-rate conversion factors for external exposure to photon and electron radiation from radionuclides occurring in routine releases from nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1980-01-01

    Dose-rate conversion factors for external exposure to photon and electron radiation are calculated for 240 radionuclides of potential importance in routine releases from nuclear fuel cycle facilities. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each exposure mode, dose-rate conversion factors for photons and electrons are calculated for tissue-equivalent material at the body surface of an exposed individual. Dose-rate conversion factors for photons only are calculated for 22 body organs. (author)

  3. Characterizing risk factors for pediatric lamp oil product exposures.

    Science.gov (United States)

    Sheikh, S; Chang, A; Kieszak, S; Law, R; Bennett, H K W; Ernst, E; Bond, G R; Spiller, H A; Schurz-Rogers, H; Chu, A; Bronstein, A C; Schier, J G

    2013-11-01

    Poisonings from lamp oil ingestion continue to occur worldwide among the pediatric population despite preventive measures such as restricted sale of colored and scented lamp oils. This suggests that optimal prevention practices for unintentional pediatric exposures to lamp oil have yet to be identified and/or properly implemented. To characterize demographic, health data, and potential risk factors associated with reported exposures to lamp oil by callers to poison centers (PCs) in the US and discuss their public health implications. This was a two part study in which the first part included characterizing all exposures to a lamp oil product reported to the National Poison Data System (NPDS) with regard to demographics, exposure, health, and outcome data from 1/1/2000 to 12/31/2010. Regional penetrance was calculated using NPDS data by grouping states into four regions and dividing the number of exposure calls by pediatric population per region (from the 2000 US census). Temporal analyses were performed on NPDS data by comparing number of exposures by season and around the July 4th holiday. Poisson regression was used to model the count of exposures for these analyses. In the second part of this project, in order to identify risk factors we conducted a telephone-based survey to the parents of children from five PCs in five different states. The 10 most recent lamp oil product exposure calls for each poison center were systematically selected for inclusion. Calls in which a parent or guardian witnessed a pediatric lamp oil product ingestion were eligible for inclusion. Data on demographics, exposure information, behavioral traits, and health were collected. A descriptive analysis was performed and Fisher's exact test was used to evaluate associations between variables. All analyses were conducted using SAS v9.3. Among NPDS data, 2 years was the most common patient age reported and states in the Midwestern region had the highest numbers of exposure calls compared to

  4. Exposure buildup factors for a cobalt-60 point isotropic source for single and two layer slabs

    International Nuclear Information System (INIS)

    Chakarova, R.

    1992-01-01

    Exposure buildup factors for point isotropic cobalt-60 sources are calculated by the Monte Carlo method with statistical errors ranging from 1.5 to 7% for 1-5 mean free paths (mfp) thick water and iron single slabs and for 1 and 2 mfp iron layers followed by water layers 1-5 mfp thick. The computations take into account Compton scattering. The Monte Carlo data for single slab geometries are approximated by Geometric Progression formula. Kalos's formula using the calculated single slab buildup factors may be applied to reproduce the data for two-layered slabs. The presented results and discussion may help when choosing the manner in which the radiation field gamma irradiation units will be described. (author)

  5. Effects of UVB irradiation on keratinocyte growth factor (KGF) and receptor (KGFR) expression in cultured human keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Y.; Lee, H.S.T.; Kooshesh, F.; Fujisawa, H.; Sauder, D.N.; Kondo, S. [Univ. of Toronto, Sunnybrook Health Science Centre, Div. of Dermatology, Toronto (Canada)

    1996-06-01

    Keratinocyte growth factor (KGF) and its receptor (KGFR) are thought to play important roles in normal keratinocyte growth and differentiation. Since UVB radiation is known to influence keratinocyte growth, we sought to determine whether UVB would alter the expression of KGF and KGFR. Using a reverse-transcription coupled polymerase chain reaction (RT-PCR), the present study examined the expression of KGF and KGFR mRNA in cultured normal human keratinocytes exposed to UVB irradiation. Total cellular RNA was extracted from cultured keratinocytes at various time points after irradiation, reverse transcribed and used for PCR amplification using primers specific for KGF and KGFR. Constitutive expression of KGFR mRNA, but not KGF mRNA, was detected in normal cultured human keratinocytes. After UVB irradiation at 300 J/m{sup 2}, the KGF mRNA remained undetectable while the KGFR mRNA level was significantly decreased. The down-regulation of KGFR mRNA expression was also confirmed by Northern blot analysis. Immunohistochemical studies demonstrated a decreased positive signal of KGFR in human keratinocytes after UVB irradiation. Our results suggest a possible role for the KGF-KGFR signalling pathway in the skin after exposure to UVB, and that UVB-induced growth inhibition of keratinocytes in hyperproliferative skin disorders may be related to downregulation of KGFR. (au) 39 refs.

  6. Irradiation inactivation of some antinutritional factors in plant seeds

    International Nuclear Information System (INIS)

    Abu-Tarboush, H.M.

    1998-01-01

    Effects of gamma-irradiation (1.0-10 kGy) on trypsin, chymotrypsin, and alpha-amylase inhibitors of soybean and Moringa peregrina seeds on tannin of sorghum, gossypol of cottonseed, and in vitro digestibility of soybean were investigated. A dose of 10.0 kGy caused decreases in trypsin (by 34.9%) and chymotrypsin (by 71.4%) inhibitor activities in soybean defatted flour, whereas its in vitro digestibility increased from 79.8 to 84.2%. The alpha-amylase inhibitor activity of Al-Yassar (M. peregrina) was decreased by 43.6 and 47.8% upon treatment of 7.0 and 10.0 kGy, respectively. Doses of 10.0 and 7.0 kGy significantly reduced the tannin content in Shahlla sorghum but not in Hemaira sorghum. Total and free gossypol contents were slightly reduced by irradiation

  7. Enhancement of tumor cell killing in vitro by pre- and post-irradiation exposure to aclacinomycin A

    International Nuclear Information System (INIS)

    Bill, C.A.; Mendoza, A.; Vrdoljak, E.; Tofilon, P.J.

    1993-01-01

    Aclacinomycin A (ACM), a potent inducer of leukemic cell differentiation, significantly enhances the radiosensitivity of a human colon tumor cell line (Clone A) when cultures are exposed to 15-nM concentrations for 3 days before irradiation. We now demonstrate that incubation with ACM after irradiation can also enhance Clone A cell killing. The maximum increase in cell killing, based on colony-forming ability, occurred when Clone A cells were exposed for 1 h to 5 μM ACM model added 1 or 2 h after irradiation. The post-irradiation ACM protocol reduced the terminal slope (as reflected by D o ) of the radiation cell survival curve with no change in the low-dose, shoulder region of the curve (D q value). In contrast, for pre-irradiation treatment with ACM (15 nM, 3 days), the shoulder region of the curve was reduced with no change in the terminal slope. For pre- and post-irradiation ACM treatment the dose enhancement factors at 0.10 survival were 1.22 and 1.28, respectively. When ACM was given both before and after irradiation both the shoulder and terminal slope values decreased to produce a dose enhancement factor at a surviving fraction of 0.10 of 1.50. These data suggest that the enhanced cell killing produced by pre- and post-irradiation treatment with ACM is achieved through different mechanisms. (author) 26 refs., 3 tabs., 2 figs

  8. Examining exposure reciprocity in a resin based composite using high irradiance levels and real-time degree of conversion values.

    Science.gov (United States)

    Selig, Daniela; Haenel, Thomas; Hausnerová, Berenika; Moeginger, Bernhard; Labrie, Daniel; Sullivan, Braden; Price, Richard B T

    2015-05-01

    Exposure reciprocity suggests that, as long as the same radiant exposure is delivered, different combinations of irradiance and exposure time will achieve the same degree of resin polymerization. This study examined the validity of exposure reciprocity using real time degree of conversion results from one commercial flowable dental resin. Additionally a new fitting function to describe the polymerization kinetics is proposed. A Plasma Arc Light Curing Unit (LCU) was used to deliver 0.75, 1.2, 1.5, 3.7 or 7.5 W/cm(2) to 2mm thick samples of Tetric EvoFlow (Ivoclar Vivadent). The irradiances and radiant exposures received by the resin were determined using an integrating sphere connected to a fiber-optic spectrometer. The degree of conversion (DC) was recorded at a rate of 8.5 measurements a second at the bottom of the resin using attenuated total reflectance Fourier Transform mid-infrared spectroscopy (FT-MIR). Five specimens were exposed at each irradiance level. The DC reached after 170s and after 5, 10 and 15 J/cm(2) had been delivered was compared using analysis of variance and Fisher's PLSD post hoc multiple comparison tests (alpha=0.05). The same DC values were not reached after the same radiant exposures of 5, 10 and 15 J/cm(2) had been delivered at an irradiance of 3.7 and 7.5 W/cm(2). Thus exposure reciprocity was not supported for Tetric EvoFlow (p<0.05). For Tetric EvoFlow, there was no significant difference in the DC when 5, 10 and 15J/cm(2) were delivered at irradiance levels of 0.75, 1.2 and 1.5 W/cm(2). The optimum combination of irradiance and exposure time for this commercial dental resin may be close to 1.5 W/cm(2) for 12s. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  9. Method for determining correction factors induced by irradiation of ionization chamber cables in large radiation field

    International Nuclear Information System (INIS)

    Rodrigues, L.L.C.

    1988-01-01

    A simple method was developed to be suggested to hospital physicists in order to be followed during large radiation field dosimetry, to evaluate the effects of cables, connectors and extension cables irradiation and to determine correction factors for each system or geometry. All quality control tests were performed according to the International Electrotechnical Commission for three clinical dosimeters. Photon and electron irradiation effects for cables, connectors and extention cables were investigated under different experimental conditions by means of measurements of chamber sensitivity to a standard radiation source of 90 Sr. The radiation induced leakage current was also measured for cables, connectors and extension cables irradiated by photons and electrons. All measurements were performed at standard dosimetry conditions. Finally, measurements were performed in large fields. Cable factors and leakage factors were determined by the relation between chamber responses for irradiated and unirradiated cables. (author) [pt

  10. Long term effects of exposure to ionizing irradiation on periodontal health status – the Tinea Capitis cohort study

    Directory of Open Access Journals (Sweden)

    Siegal eSadetzki

    2015-10-01

    Full Text Available Studies among long term survivors of childhood cancer who had received high dose irradiation therapy of 4-60 Gy, demonstrated acute and chronic dental effects including periodontal diseases. However, the possible effects of low to moderate doses of radiation on dental health are sparse. The aim of this study is to investigate the association between childhood exposure to low-moderate doses of ionizing radiation and periodontal health following 50 years from the exposure. The study population included 253 irradiated subjects (treated for Tinea Capitis in the 1950s and, 162 non-irradiated subjects, treated for Tinea Capitis in the 1950s. The estimated dose to the teeth was 0.2-0.4Gy. Dental examination was performed according to the Community Periodontal Index (CPI. Socio-economic and health behavior variables were obtained through a personal questionnaire. Periodontal disease was operationally defined as deep periodontal pockets. A multivariate logistic regression model was used for the association of irradiation status and other independent variables with periodontal status.The results showed that among the irradiated subjects, 23% (95% CI 18%-28% demonstrated complete edentulousness or insufficient teeth for CPI scoring as compared to 13% (95% CI 8%-19% among the non-irradiated subjects (p=0.01. Periodontal disease was detected among 54% of the irradiated subjects as compared to 40% of the non-irradiated (p=0.008. Controlling for education and smoking, the ORs for the association between radiation and periodontal disease were 1.61 (95% CI 1.01-2.57 and 1.95 (95% CI 1.1-3.5 for ever never and per 1 Gy absorbed in the salivary gland, respectively. In line with other studies, a protective effect for periodontal diseases among those with high education and an increased risk for ever smokers were observed. In conclusion, childhood exposure to low-moderate doses of ionizing radiation might be associated with later outcomes of dental health. The

  11. Photostability Characterization of Wood Polymer Composites of Polyvinyl Chloride and Rice Husk to Ultra-Violet Irradiation Exposure

    Directory of Open Access Journals (Sweden)

    Jais Farhana Hazwanee M.

    2016-01-01

    Full Text Available In this study, the photostability of wood polymer composites (WPC was assessed by using ultra-violet accelerated weathering test. Meanwhile, the mechanical properties of WPC show strength improvement at prolonged UV irradiation exposure with 43.21 MPa and maximum strain of 4.08 % at 5000 hours and 1000 hours UV irradiation exposure respectively. The colour stability of WPC was improved by addition of Ultraviolet (UV stabilizer during pre-mixing process which shows positive effect on the colour stability and prevented chalking of the composites for external use. Generally, discolourations of WPC during test exposure were caused by degradation of both wood and plastic. Therefore, incorporation with pigments and other additives gives improvement to the photostability of WPC. This is based on the increment of WPCs mechanical property while the morphological fracture surface of dumbbell test specimens revealed the pull out rice husk fiber which contributed to the distribution of load in the WPC samples.

  12. Woodstove exposure as a risk factor for airway obstruction

    Directory of Open Access Journals (Sweden)

    Alexandros Mpagordakis

    2015-06-01

    Full Text Available Background: The recent financial crisis in Greece has significantly increased woodstove use and therefore the indoor air pollution of the household atmosphere. Related studies have shown that indoor air pollution is associated with the onset of obstructive airway diseases, especially in women who are occupied with household duties. Aim: To investigate whether the woodstove exposure is a risk factor of obstructive airway disease especially in nonsmoking women. Methods: In this cross-sectional study participated 410 individuals (51.7% women, mean age 56,1 ± 13,0 years, ranging from 40 to 93 years old who visited eight Primary Health Care Settings on the island of Crete, Greece. A spirometry testing was performed to assess the degree of airflow limitation setting criteria the fixed ratio of spirometry values (FEV1 / FVC 17] were establish in non-smoker women who were exposed for 30.2 years to woodstove smoke compared to non-COPD non-smoker women (11.8 years exposure, despite the fact that interactions terms (female gender, smoking, woodstove use, cough with sputum production were not associated with COPD development. Conclusion: The present study confirms that woodstove exposure (about 30 years is associated with Airway Obstruction in non-smoker women. Also, a greater woodstove exposure is indicative of a greater prevalence of airflow limitation and a greater COPD-related symptoms.

  13. Effects of neutron-gamma or gamma irradiations on plasma clotting factors. Effect of a treatment by substituted factors

    International Nuclear Information System (INIS)

    Mestries, J.C.; Martin, S.; Janodet, D.; Herodin, F.; Gourmelon, P.; Fatome, M.

    1991-01-01

    Neutron-gamma irradiation of the baboon at lethal dose altered the plasma clotting factors and induced a fibrinoformation alteration which occurred shortly before death. These disturbances, which were not found after gamma irradiation, could explain the importance of the haemorrhagic syndrome. Treatment by P.P.S.B. (factors II, VII, X and IX) counteracted the alterations of the plasma clotting factors, but had no influence on the lethality nor on the fibrinoformation alteration which seems to be an important cause of death [fr

  14. Evidence against a systemic humoral factor controlling the intestinal compensatory response following X-irradiation

    International Nuclear Information System (INIS)

    Sharp, J.G.; Osborne, J.W.; Iowa Univ., Iowa City

    1981-01-01

    The investigation was devised to determine whether changes noted in the unirradiated duodenum and colon of single rats after X-irradiation of only the exteriorized rat jejunum and ileum are mediated by a systemic humoral factor. Littermate Holtzman male rats were joined in parabiosis and one month later, the temporarily exteriorized jejunum and ileum of one member was exposed to 1.000 R of 250 kVp X-irradiation. Two days after X-irradiation, and 1, 12 and 24 h after 1 μCi/g bodyweight 3 H-thymidine was injected i.p. rats were sacrificed and appropriate tissues removed. Single rats which had the exteriorized jejunum and ileum irradiated were studied from 1-3 days after irradiation. Crypt cell migration rates were determined employing autoradiography. Tritium content and columnar cell migration rate in duodenum and colon of unirradiated rats compared to irradiated rats indicated that irradiation of one member of the pair had no effect on tritium incorporation or epithelial cell migration in the duodenum or colon of the unirradiated partner. Epithelial cell proliferation and crypt cell migration were increased in unirradiated duodenum and colon of single intestine-irradiated rats. Essentially the same changes were seen in the irradiated member of a parabiotic pair, but none of these changes were noted in the unirradiated member. The absence of stimulation in the unirradiated parabiont suggests that either a systemic humoral factor is not present after X-irradiation or is not present in sufficient concentration to be detected by these methods. (orig./MG)

  15. The effect of the timing of prenatal exposure to x-irradiation on Purkinje cell numbers in rat cerebellum

    International Nuclear Information System (INIS)

    Miki, T.; Satriotomo, I.; Matsumoto, Y.; Kuma, H.; Takeuchi, Y.; Gu

    2003-01-01

    Full text: Prenatal exposure of the developing brain to X-irradiation is known to cause various deleterious consequences. We have examined the effects of prenatal X-irradiation on the development of the cerebellum. Wistar rats were exposed to 1.5 Gy X-irradiation either on the 14, 15 or 16th day of gestation (E14, E15, E16). Sham-irradiated animals were used as controls. At seven postnatal weeks of age, male rats were deeply anesthetized and killed by intracardiac perfusion with 2.5 % glutaraldehyde in 0.1 M phosphate buffer. The unbiased stereological procedure known as the fractionator method was used to estimate the total number of Purkinje cells in the cerebellum. Body and cerebellar weights from E14 and E15, but not E16 irradiated rats showed significant deficits compared to control animals. Rats irradiated on E16 and control rats had about 285,100 - 304,800 Purkinje cells in the cerebellum. There was no significant difference between these values. However, E14 and E15 irradiated animals had about 117,500 and 196,300 Purkinje cells, respectively. These estimates were significantly different from those observed in both control and E16 irradiated rats. Given that the phase of division of Purkinje cell progenitors is mainly between E14-E15 and the phase of differentiation and migration is between E16-E20, it is concluded that the vulnerable period of the Purkinje cells to X-irradiation closely overlaps the phase of division of progenitors

  16. A study of the energy absorption and exposure buildup factors of some anti-inflammatory drugs

    International Nuclear Information System (INIS)

    Ekinci, Neslihan; Kavaz, Esra; Özdemir, Yüksel

    2014-01-01

    Human radiation exposure is increasing due to radiation development in science and technology. The development of radioprotective agents is important for protecting patients from the side effects of radiotherapy and for protecting the public from unwanted irradiation. Radioprotective agents are used to reduce the damage caused by radiation in healthy tissues. There are several classes of radioprotective compounds that are under investigation. Analgesics and anti-inflammatory compounds are being considered for treating or preventing the effects of damage due to radiation exposure, or for increasing the chance of survival after exposure to a high dose of radiation. In this study, we investigated the radioprotective effects of some analgesic and anti-inflammatory compounds by evaluating buildup factors. The gamma ray energy absorption (EABF) and exposure buildup factors (EBF) were calculated to select compounds in a 0.015–15 MeV energy region up to a penetration depth of 40 mfp (mean free path). Variations of EABF and EBF with incident photon energy and penetration depth elements were also investigated. Significant variations in both EABF and EBF values were observed for several compounds at the moderate energy region. At energies below 0.15 MeV, EABF and EBF values increased with decreasing equivalent atomic number (Z eq ) of the samples. In addition, EABF and EBF were the largest for ibuprofen, aspirin, paracetamol, naproxen and ketoprofen at 0.05 and 0.06 MeV, respectively, and the EABF value was 0.1 MeV for aceclofenac. From these results, we concluded that the buildup of photons is less for aceclofenac compared to other materials. - Highlights: • Buildup factors of anti-inflammatory drugs have been calculated by a G-P fitting method. • Z eff of diclofenac was observed higher than other compounds. • It was found that buildup of photons is less for aceclofenac and diclofenac. • It would be appealing to use aceclofenac and diclofenac as radioprotective

  17. Ultraviolet spectral distribution and erythema-weighted irradiance from indoor tanning devices compared with solar radiation exposures.

    Science.gov (United States)

    Sola, Yolanda; Baeza, David; Gómez, Miguel; Lorente, Jerónimo

    2016-08-01

    Concern regarding the impact of indoor tanning devices on human health has led to different regulations and recommendations, which set limits on erythema-weighted irradiance. Here, we analyze spectral emissions from 52 tanning devices in Spanish facilities and compare them with surface solar irradiance for different solar zenith angles. Whereas most of the devices emitted less UV-B radiation than the midday summer sun, the unweighted UV-A irradiance was 2-6 times higher than solar radiation. Moreover, the spectral distributions of indoor devices were completely different from that of solar radiation, differing in one order of magnitude at some UV-A wavelengths, depending on the lamp characteristics. In 21% of the devices tested, the erythema-weighted irradiance exceeded 0.3Wm(-2): the limit fixed by the European standard and the Spanish regulation. Moreover, 29% of the devices fall within the UV type 4 classification, for which medical advice is required. The high variability in erythema-weighted irradiance results in a wide range of exposure times to reach 1 standard erythemal dose (SED: 100Jm(-2)), with 62% of devices requiring exposures of UV-A dose during this time period would be from 1.4 to 10.3 times more than the solar UV-A dose. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Microstructural stability of austenitic stainless steels on exposure to irradiation and elevated temperatures

    International Nuclear Information System (INIS)

    Parameswaran, P.; Radhika, M.; Saroja, S.; Vijayalakshmi, M.; Nanda Gopal, M.

    2011-01-01

    Cold worked 316 stainless steels employed as core material in fast reactors on exposure to neutron irradiation to 40 dpa at ∼ 450 deg C have resulted in microstructural changes in terms of formation of voids and extensive precipitation of carbides, eta phase and nickel silicides. As a consequence there is degradation in the mechanical properties of the material, particularly ductility. In order to achieve higher burnup it is essential to find better materials, which would exhibit less void swelling and retain the microstructure over long radiation doses. Accordingly alloy D9 with appropriate modifications of Ni and Cr content with Ti additions has been developed. Further modification of alloy D9 with respect to minor alloying additions namely Si and P is being studied, in order to enhance the radiation resistance for extending the service life of components. The effectiveness of these elements can be achieved if and only if they are retained in solution over long time of exposure at high temperatures and irradiation. Therefore, the thermal stability of the newly developed improved D9 alloys, with a constant Ti:C ratio and different levels of Si and P has been studied with respect to microstructural evolution and its influence on the mechanical properties. Thermal aging behavior of the alloy with varying titanium contents at elevated temperatures was also studied in detail to identify the optimum alloying levels. The alloys in the 20% cold worked condition exhibit austenitic grains interspersed with bands of fine cold worked grains. On aging in the temperature range of 873-1073K for various durations upto two years the alloy showed the presence of different phases such as M 23 C 6 , intermetallics and TiC whose quantity varies with temperature. The hardness values showed a trend of an initial increase in all the alloys but at longer times the hardness either showed saturation or a decrease followed by saturation. The microstructural parameters like grain size and

  19. Exposure Scenarios and Unit Dose Factors for the Hanford Immobilized Low Activity Tank Waste Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    RITTMANN, P.D.

    1999-12-29

    Exposure scenarios are defined to identify potential pathways and combinations of pathways that could lead to radiation exposure from immobilized tank waste. Appropriate data and models are selected to permit calculation of dose factors for each exposure

  20. Heart irradiation as a risk factor for radiation pneumonitis

    International Nuclear Information System (INIS)

    Huang, Ellen X.; El Naqa, Issam; Deasy, Joseph O.; Bradley, Jeffrey D.; Hope, Andrew J.; Lindsay, Patricia E.; Trovo, Marco

    2011-01-01

    Purpose. To investigate the potential role of incidental heart irradiation on the risk of radiation pneumonitis (RP) for patients receiving definitive radiation therapy for non-small-cell lung cancer (NSCLC). Material and methods. Two hundred and nine patient datasets were available for this study. Heart and lung dose-volume parameters were extracted for modeling, based on Monte Carlo-based heterogeneity corrected dose distributions. Clinical variables tested included age, gender, chemotherapy, pre-treatment weight-loss, performance status, and smoking history. The risk of RP was modeled using logistic regression. Results. The most significant univariate variables were heart related, such as heart heart V65 (percent volume receiving at least 65 Gy) (Spearman Rs = 0.245, p < 0.001). The best-performing logistic regression model included heart D10 (minimum dose to the hottest 10% of the heart), lung D35, and maximum lung dose (Spearman Rs 0.268, p < 0.0001). When classified by predicted risk, the RP incidence ratio between the most and least risky 1/3 of treatments was 4.8. The improvement in risk modeling using lung and heart variables was better than using lung variables alone. Conclusions. These results suggest a previously unsuspected role of heart irradiation in many cases of RP

  1. Irradiation Creep and Swelling of Russian Ferritic-Martensitic Steels Irradiated to Very High Exposures in the BN-350 Fast Reactor at 305-335 degrees C

    International Nuclear Information System (INIS)

    Konobeev, Yury V.; Dvoriashin, Alexander M.; Porollo, S.I.; Shulepin, S.V.; Budylkin, N.I.; Mironova, Elena G.; Garner, Francis A.

    2003-01-01

    Russian ferritic/martensitic (F/M) steels EP-450, EP-852 and EP-823 were irradiated in the BN-350 fast reactor in the form of gas-pressurized creep tubes. The first steel is used in Russia for hexagonal wrappers in fast reactors. The other steels were developed for compatibility with Pb-Bi coolants and serve to enhance our understanding of the general behavior of this class of steels. In an earlier paper we published data on irradiation creep of EP-450 and EP-823 at temperatures between 390 and 520C, with dpa levels ranging from 20 to 60 dpa. In the current paper new data on the irradiation creep and swelling of EP-450 and EP-852 at temperatures between 305 and 335C and doses ranging from 61 to 89 dpa are presented. Where comparisons are possible, it appears that these steels exhibit behavior that is very consistent with that of Western steels. Swelling is relatively low at high neutron exposure and confined to temperatures <420C, but may be camouflaged somewhat by precipitation-related densification. These irradiation creep studies confirm that the creep compliance of F/M steels is about one-half that of austenitic steels.

  2. Studies of factors for speeding up mellowness of yellow rice wine by irradiation

    International Nuclear Information System (INIS)

    Hua Fenmei; Chen Qiufang; Yu Yuntao; Huang Liugen

    1991-01-01

    The paper described the research result of the factors for speeding up mellowness of yellow rice wine by irradiation of low dosage. The effect of speeding up its mellowness was gained through the research of different dosage, irradiated temperature, different container, space of container and storing temperature etc.. The experiment indicated that the best dosage was 100-600 Gy with 30-40 deg C tempreature; the pottery container for wraping wine was better than the glass one; the better space was 100 ml empty of one container and the storing time of irradiated wine covered 5-6 months

  3. Gene expression in skin tumors induced in hairless mice by chronic exposure to ultraviolet B irradiation

    International Nuclear Information System (INIS)

    Sato, Hiromi; Tanaka, Misao; Kobayashi, Shizuko; Suzuki, Junko S.; Ogiso, Manabu; Tohyama, Chiharu

    1997-01-01

    We investigated the expressions of c-Ha-ras, c-jun, c-fos, c-myc genes and p53 protein in the development of skin tumours induced by chronic exposure to UVB without a photosensitizer using hairless mice. When mice were exposed to UVB at a dose of 2 kJ/m 2 three times a week, increased c-Ha-ras and c-myc transcripts were detected after only 5 weeks of exposure, while no tumour appeared on the exposed skin. The increase in gene expression continued until 25 weeks, when tumours, identified pathologically as mainly squamous cell carcinomas (SCC), developed in the dorsal skin. In these SCC, overexpression of c-fos mRNA was also observed along with the increases in c-Ha-ras and c-myc. A single dose of UVB (2 kJ/m 2 ) applied to the backs of hairless mice transiently induced overexpression of the early event genes c-fos, c-jun and c-myc, but not c-Ha-ras, in the exposed area of skin. Accumulation of p53 protein was determined by Western blotting analysis of immunohistochemistry using monoclonal antibodies PAb 240 or 246, which recognize mutant or wide type, respectively. In the SCC, a mutant p53 protein accumulated in the cytoplasm and nucleus. After single-dose irradiation, the increased wild-type p53 protein was observed in the nuclei of epidermal cells. The present results suggest that overexpression of the c-fos, c-myc and c-Ha-ras genes, and the mutational changes in p53 protein might be associated with skin photocarcinogenesis. Moreover, overexpression of the c-Ha-ras and c-myc genes might be an early event in the development of UVB-induced skin tumors in mice. (author)

  4. Analyzing seasonal patterns of wildfire exposure factors in Sardinia, Italy.

    Science.gov (United States)

    Salis, Michele; Ager, Alan A; Alcasena, Fermin J; Arca, Bachisio; Finney, Mark A; Pellizzaro, Grazia; Spano, Donatella

    2015-01-01

    In this paper, we applied landscape scale wildfire simulation modeling to explore the spatiotemporal patterns of wildfire likelihood and intensity in the island of Sardinia (Italy). We also performed wildfire exposure analysis for selected highly valued resources on the island to identify areas characterized by high risk. We observed substantial variation in burn probability, fire size, and flame length among time periods within the fire season, which starts in early June and ends in late September. Peak burn probability and flame length were observed in late July. We found that patterns of wildfire likelihood and intensity were mainly related to spatiotemporal variation in ignition locations, fuel moisture, and wind vectors. Our modeling approach allowed consideration of historical patterns of winds, ignition locations, and live and dead fuel moisture on fire exposure factors. The methodology proposed can be useful for analyzing potential wildfire risk and effects at landscape scale, evaluating historical changes and future trends in wildfire exposure, as well as for addressing and informing fuel management and risk mitigation issues.

  5. Hematopoietic regulatory factors produced in long-term murine bone marrow cultures and the effect of in vitro irradiation

    International Nuclear Information System (INIS)

    Gualtieri, R.J.; Shadduck, R.K.; Baker, D.G.; Quesenberry, P.J.

    1984-01-01

    The nature of hematopoietic regulatory factors elaborated by the adherent (stromal) cells of long-term murine bone marrow cultures and the effect of in vitro stromal irradiation (XRT) on the production of these factors was investigated. Using an in situ stromal assay it was possible to demonstrate stromal elaboration of at least two colony-stimulating activities, ie, granulocyte/macrophage colony-stimulating activity (G/M-CSA) and megakaryocyte colony-stimulating activity (Meg-CSA). Exposure of the stroma to XRT resulted in dose-dependent elevations of both activities that correlated inversely with total myeloid cell mass. Mixture experiments that combined control and irradiated stroma revealed that the hematopoietically active control stroma could block detection of XRT-related G/M-CSA elevations. Antiserum directed against purified L cell colony-stimulating factor (CSF) reduced granulocyte/macrophage colony formation in the target layer but did not effect the increased Meg-CSA. While a radioimmunoassay for L-cell type CSF was unable to detect significant differences in concentrated media from control and irradiated cultures, bioassays of these media revealed XRT-related G/M-CSA elevations. These results indicate that the G/M-CSA elaborated in these cultures is immunologically distinct from the Meg-CSA produced, and although distinct from L cell CSF, the G/M-CSA is crossreactive with the L cell CSF antiserum. Morphologic, histochemical, and factor VII antigen immunofluorescent studies were performed on the stromal cell population responsible for production of these stimulatory activities. In addition to ''fat'' cells, the stromal cells remaining after XRT were composed of two predominant cell populations. These included a major population of acid phosphatase and nonspecific esterase-positive macrophage-like cells and a minor population of factor VII antigen negative epithelioid cells

  6. 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

  7. Patient exposure: description of cumulative irradiation of patients treated in interventional cardiology; Exposition des patients: description de l'irradiation cumulee des patients traites en cardiologie interventionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Odile Bernier, M.O. [Institut de Radioprotection et de Surete Nucleaire, Laboratoire d ' Epidemiologie, 92 - Fontenay aux Roses (France)

    2009-07-01

    Despite its clinical benefits, interventional cardiology induces cumulative exposure to ionizing radiation and may entail an important irradiation of the patient at the cutaneous level as well as for organs at the vicinity of the heart. The author briefly reports a study performed on a sample of 1591 patients who have been submitted to at least one corono-graphy or one angioplasty during 2005. Based on clinical characteristics and dose-area-product measurements, the doses received by lung, oesophagus, bone medulla and breast have been computed

  8. Characterization of the multiple drug resistance phenotype expressed by tumour cells following in vitro exposure to fractionated X-irradiation

    International Nuclear Information System (INIS)

    Hill, B.T.; McClean, S.; Hosking, L.; Shellard, S.; Dempke, W.; Whelan, R.

    1992-01-01

    The major clinical problem of the emergence of drug resistant tumor cell populations is recognized in patients previously treated with antitumor drugs and with radiotherapy. It is proposed that, although radiation-induced vascular fibrosis may limit drug delivery to the tumor, exposure to radiation may 'induce' or 'select for' drug resistance. This hypothesis was examined by establishing in vitro model systems to investigate the resistance phenotype of tumor cells following exposure to X-rays. Characteristically tumor cells surviving exposure to a series of fractions of X-irradiation are shown to have consistently expressed resistance to multiple drugs, including the Vinca alkaloids and the epipodophyllotoxins. Currently this research is aimed at determining whether distinctive resistance mechanisms operate depending on whether resistance results following drug or X-ray exposure. Initial results indicate that whilst some common mechanisms operate, drug resistant tumor cells identified following exposure to X-irradiation appear to exhibit a novel multidrug resistance phenotype. (author). 13 refs., 1 tab

  9. Effect of low molecular fraction of thymus humoral factor on blood formation processes of irradiated mice

    International Nuclear Information System (INIS)

    Stolyarova, T.V.; Skobel'tsyna, E.S.; Grinberg, S.M.; Kruglikov, I.L.; Korotaev, G.K.; Tepelina, O.M.; Il'ina, T.I.

    1982-01-01

    The effect of low-molecular fraction of thymus humoral factor on blood formation in mice irradiated at 4 Gy was studied. It is shown that injection of low-molecular fraction of thymus hymoral factor to irradiated animals affects proliferative processes in spleen and bone marrow, however the degree of the effect depends on the injection scheme of the preparation. Application of mathematical planning methods of the experiment enables to analyze various injection schemes of low-molecular fraction of thymus humoral factor on the investigated indices. The optimal scheme of preparation injection is determined: 1st injection with the dose of 10 mkg/kg following 4 hour after irradiation, 2d injection - with the same dose in 7-21 days

  10. Effects of cryogen spray cooling and high radiant exposures on selective vascular injury during laser irradiation of human skin.

    Science.gov (United States)

    Tunnell, James W; Chang, David W; Johnston, Carol; Torres, Jorge H; Patrick, Charles W; Miller, Michael J; Thomsen, Sharon L; Anvari, Bahman

    2003-06-01

    Increasing radiant exposure offers a means to increase treatment efficacy during laser-mediated treatment of vascular lesions, such as port-wine stains; however, excessive radiant exposure decreases selective vascular injury due to increased heat generation within the epidermis and collateral damage to perivascular collagen. To determine if cryogen spray cooling could be used to maintain selective vascular injury (ie, prevent epidermal and perivascular collagen damage) when using high radiant exposures (16-30 J/cm2). Observational study. Academic hospital and research laboratory. Twenty women with normal abdominal skin (skin phototypes I-VI). Skin was irradiated with a pulsed dye laser (wavelength = 585 nm; pulse duration = 1.5 milliseconds; 5-mm-diameter spot) using various radiant exposures (8-30 J/cm2) without and with cryogen spray cooling (50- to 300-millisecond cryogen spurts). Hematoxylin-eosin-stained histologic sections from each irradiated site were examined for the degree of epidermal damage, maximum depth of red blood cell coagulation, and percentage of vessels containing perivascular collagen coagulation. Long cryogen spurt durations (>200 milliseconds) protected the epidermis in light-skinned individuals (skin phototypes I-IV) at the highest radiant exposure (30 J/cm2); however, epidermal protection could not be achieved in dark-skinned individuals (skin phototypes V-VI) even at the lowest radiant exposure (8 J/cm2). The red blood cell coagulation depth increased with increasing radiant exposure (to >2.5 mm for skin phototypes I-IV and to approximately 1.2 mm for skin phototypes V-VI). In addition, long cryogen spurt durations (>200 milliseconds) prevented perivascular collagen coagulation in all skin types. Cryogen spurt durations much longer than those currently used in therapy (>200 milliseconds) may be clinically useful for protecting the epidermis and perivascular tissues when using high radiant exposures during cutaneous laser therapies

  11. Evaluation of nonuniform field exposures with coupling factors

    International Nuclear Information System (INIS)

    Sunohara, Tetsu; Hirata, Akimasa; Laakso, Ilkka; De Santis, Valerio; Onishi, Teruo

    2015-01-01

    In this study, the safety compliance for nonuniform field exposures is discussed using coupling factor concepts. The coupling factor, which is defined in the International Electrotechnical Commission 62311 standard, is extended to consider the effects of harmonics and also to apply to the specific absorption rate (for frequencies up to 30 MHz). The proposed compliance procedure is applied to and demonstrated for a prototype wireless power transfer (WPT) system with induction coupling operating at the fundamental frequency in 140 kHz band. First, measurements confirm that the perturbation of the external magnetic field strength and S 11 parameter of a one-loop antenna by a human-equivalent phantom are sufficiently small, suggesting the applicability of the magneto-quasi-static approximation to frequencies up to 30 MHz. Then, the frequency characteristics of the coupling factor are derived for the WPT system. For the prototype system that is not optimized for commercial usage, the maximum allowable transmitting power is relaxed by a factor of 23 with the proposed procedure. The contribution of the harmonics decreased the allowable transmitting power by 39%, indicating their importance for safety compliance. (paper)

  12. Evaluation of nonuniform field exposures with coupling factors.

    Science.gov (United States)

    Sunohara, Tetsu; Hirata, Akimasa; Laakso, Ilkka; De Santis, Valerio; Onishi, Teruo

    2015-10-21

    In this study, the safety compliance for nonuniform field exposures is discussed using coupling factor concepts. The coupling factor, which is defined in the International Electrotechnical Commission 62311 standard, is extended to consider the effects of harmonics and also to apply to the specific absorption rate (for frequencies up to 30 MHz). The proposed compliance procedure is applied to and demonstrated for a prototype wireless power transfer (WPT) system with induction coupling operating at the fundamental frequency in 140 kHz band. First, measurements confirm that the perturbation of the external magnetic field strength and S11 parameter of a one-loop antenna by a human-equivalent phantom are sufficiently small, suggesting the applicability of the magneto-quasi-static approximation to frequencies up to 30 MHz. Then, the frequency characteristics of the coupling factor are derived for the WPT system. For the prototype system that is not optimized for commercial usage, the maximum allowable transmitting power is relaxed by a factor of 23 with the proposed procedure. The contribution of the harmonics decreased the allowable transmitting power by 39%, indicating their importance for safety compliance.

  13. Assessment of DNA damage and repair in Mycobacterium terrae after exposure to UV irradiation.

    Science.gov (United States)

    Bohrerova, Z; Linden, K G

    2006-11-01

    Ultraviolet (UV) irradiation for drinking water treatment was examined for inactivation and subsequent dark and photo-repair of Mycobacterium terrae. UV sources tested were low pressure (monochromatic, 254 nm) and medium pressure (polychromatic UV output) Hg lamps. UV exposure resulted in inactivation, and was followed by dark or photo-repair experiments. Inactivation and repair were quantified utilizing a molecular-based endonuclease sensitive site (ESS) assay and conventional colony forming unit (CFU) viability assay. Mycobacterium terrae was more resistant to UV disinfection compared to many other bacteria, with approximately 2-log reduction at a UV fluence of 10 mJ cm(-2) ; similar to UV inactivation of M. tuberculosis. There was no difference in inactivation between monochromatic or polychromatic UV lamps. Mycobacterium terrae did not undergo detectable dark repair. Photo-repair resulted in recovery from inactivation by approximately 0.5-log in less than 30 min for both UV lamp systems. Mycobacterium terrae is able to photo-repair DNA damage within a short timeframe. The number of pyrimidine dimers induced by UV light were similar for Escherichia coli and M. terrae, however, this similarity did not hold true for viability results. There is no practical difference between UV sources for disinfection or prevention of DNA repair for M. terrae. The capability of M. terrae to photo-repair UV damage fairly quickly is important for wastewater treatment applications where disinfected effluent is exposed to sunlight. Finally, molecular based assay results should be evaluated with respect to differences in the nucleic acid content of the test micro-organism.

  14. Radioprotective effect of colony-stimulating factor on mice irradiated with 60Co γ-rays

    International Nuclear Information System (INIS)

    Zhang Junning; Wang Tao; Xu Changshao; Wang Hongyun

    1995-01-01

    Adult male mice were irradiated with γ-rays 6 Gy once or 3 Gy three times in 7 days and intraperitoneally injected with colony-stimulating factor (CSF) in high doses or low doses. Mice of the control group were injected with normal saline only. Within 30 days after irradiation, the survival rate of mice irradiated with 6 Gy γ-rays once and treated with high dose CSF was 9/25, while that in the control group was 2/25. The survival rate of mice irradiated with 3 Gy three times and treated with high dose CSF was 10/13, while that in the control group was 4/13. Moreover, the survival times of both irradiated groups treated with high dose CSF were much longer than the control groups (p<0.01). This experiment also showed that CSF could reduce the lowering of peripheral blood white blood cell counts and promote their recovery. The number of CFU-S in mice treated with CSF was much higher (23.8 +- 4.82) than in the control group (9.4 +- 4.39) (p<0.01). Therefore, CSF could recover and reconstruct the hematopoietic function of bone marrow, and prolong the survival of irradiated mice

  15. Outcome of Venom Bradykinin Potentiating Factor on Renin Angiotensin System in Irradiated Rats

    International Nuclear Information System (INIS)

    Ashry, O.; Farouk, H.; Moustafa, M.; Abu Sinn, G.; Abd ElBaset, A.

    2011-01-01

    Scorpion Venom contains a strong bradykinin potentiating factor (BPF) exhibiting angiotensin converting enzyme inhibition (ACEI). Irradiation and stimulation of renin-angiotensin system (RAS) induce oxidative stress. Interruption of the RAS by an ACEI or angiotensin II receptor blocker (ARB) losartan (LOS) and/or gamma-rays (4 Gy) were evaluated. Rats received 6 doses of BPF (1μg/g body wt) or of LOS (5 μg/g body wt). Treatment with BPF induced significant elevation in the level of potassium (K) and significant drop in the level of sodium (Na) and uric acid. Treatment with LOS significantly depressed the level of Na and uric acid compared to control. Irradiation discerned a significant elevation in malondialdehyde (MDA), advanced oxidative protein product (AOPP), aldosterone, Na, urea and creatinine, and a significant drop in the haematological values, glutathione (GSH), calcium (Ca) and uric acid. A significant decrease in MDA, aldosterone, urea, creatinine and uric acid compared to irradiated group was observed in irradiated treated groups. Irradiated animals treated with LOS showed a significant decrease in Na and chloride (Cl) compared to the irradiated group. Considerable amelioration of radiation-induced depression in haematopoiesis, improvement of oxidative stress and kidney function by BPF as ACEI or LOS as ARB are detected. Results add further identification to the properties of BPF

  16. Safety analyses of potential exposure in medical irradiation plants by Fuzzy Fault Tree

    International Nuclear Information System (INIS)

    Casamirra, Maddalena; Castiglia, Francesco; Giardina, Mariarosa; Tomarchio, Elio

    2008-01-01

    The results of Fuzzy Fault Tree (FFT) analyses of various accidental scenarios, which involve the operators in potential exposures inside an High Dose Rate (HDR) remote after-loading systems for use in brachytherapy, are reported. To carry out fault tree analyses by means of fuzzy probabilities, the TREEZZY2 computer code is used. Moreover, the HEART (Human Error Assessment and Reduction Technique) model, properly modified on the basis of the fuzzy approach, has been employed to assess the impact of performances haping and error-promoting factors in the context of the accidental events. The assessment of potential dose values for some identified accidental scenarios allows to consider, for a particular event, a fuzzy uncertainty range in potential dose estimate. The availability of lower and upper limits allows evaluating the possibility of optimization of the installation from the point of view of radiation protection. The adequacy of the training and information program for staff and patients (and their family members) and the effectiveness of behavioural rules and safety procedures were tested. Some recommendations on procedures and equipment to reduce the risk of radiological exposure are also provided. (author)

  17. Preliminary study of haemostasis in irradiated-enterectomised dog. Primary haemostasis, coagulation, plasma factors exploration

    International Nuclear Information System (INIS)

    Dubos, M.; Niaussat, P.M.; Neveux, Y.; Nguyen, T.L.; Drouet, J.; Bac, P.

    Some hematological changes due to the combined effects of ionizing radiations and surgery were studied in dogs irradiated at 250, 300 and 350R. A constant hemorrhagic syndrome was observed with an impairment of the platelets functions and a depletion of several coagulation factors [fr

  18. Influence of LBE long term exposure and simultaneous fast neutron irradiation on the mechanical properties of T91 and 316L

    Energy Technology Data Exchange (ETDEWEB)

    Stergar, E., E-mail: estergar@sckcen.be [SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium); Eremin, S.G. [RIAR, Research Institute of Atomic Reactors, Dimitrovgrad (Russian Federation); Gavrilov, S.; Lambrecht, M. [SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium); Makarov, O.; Iakovlev, V. [RIAR, Research Institute of Atomic Reactors, Dimitrovgrad (Russian Federation)

    2016-05-15

    The LEXUR–II–LBE irradiation campaign was conducted from 2011 to 2012 and was aimed to investigate the combined influence of irradiation and LBE environment. In this irradiation campaign tensile test samples, pressurized tubes and corrosion samples were irradiated in LBE filled capsules. To separate the effect of exposure to LBE and neutron irradiation a parallel furnace experiment where the samples were exposed to LBE at the irradiation temperature for the corresponding time was conducted. Here we report results of the first extracted capsule which was irradiated about 6 months and dismantled after a cooling phase to decrease activity. The results of SSRT tests for irradiated T91 show that the exposure to LBE at 350 °C for a long time leads to the appearance of liquid metal embrittlement without any pre-treatment which is usually necessary to promote LME. Irradiation increases the effect of LME on the ductility of T91. In contrast to the findings for T91 the gained results also show that tensile tests on irradiated austenitic stainless steel 316L show no influence of LBE environment on the tensile properties.

  19. Initial hospital management of irradiated and radio-contaminated victims in case of accidental exposure of populations

    International Nuclear Information System (INIS)

    Foehrenbach; Mantzarides, M.; Bonardel, G.; Gontier, E.; Laroche, P.; Carbonnieres, H. de

    2006-01-01

    The current risk of radiologic exposure of the population occurs in many circumstances. The industrial accident is remarkably illustrated by the Tchernobyl event. Another kind is still virtual but the international situation does not allow to turn this hypothesis down. It is terrorist utilization of radioactive material. In these situations, medical problems are specific and require particular knowledge about the two forms of exposure which are external irradiation and external and internal contamination. Pathophysiological mechanisms of radiation effects concerning biological tissues are similar in these situations but care actions are dedicated. These elements are mandatory for the elaboration of procedures for the reception of irradiated or contaminated victims, being wounded or not, in a first-aid department. These procedures must comprise two aspects: the recognition of the radiologic exposition and the therapeutic actions taking into account the severity of associated injuries. Diagnosis of a radioactive contamination is rather simple by external detection. Conversely, to estimate the reality of an external irradiation is much more difficult but necessary for dosimetric evaluation. This latter is of the highest importance for the prevision of delayed clinical manifestations. At the hospital level, despite the training effort for first aid departments staff, the nuclear medicine physician, specialist for radioactive contamination, can play a specific role for the preparation of the equipment, the procedures and during intervention after a radiologic event has happened. This emphasizes the obligation for him to update his knowledge about this subject. (author)

  20. Gun Violence and Children: Factors Related To Exposure and Trauma.

    Science.gov (United States)

    Slovak, Karen

    2002-01-01

    Study investigated relationship between access to firearms and parental monitoring on rural youths' exposure to gun violence, and examined the effect of gun violence exposure on mental health. Results indicated a substantial number were exposed to gun violence. Exposure was related to firearm access and parental monitoring. Implications for social…

  1. An evaluation of the effects of epidermal growth factor on irradiation lip mucosa damage in mice

    International Nuclear Information System (INIS)

    Feng Yan

    1994-01-01

    The effect of epidermal growth factor (EGF) on lip mucosa damage by irradiation was explored in mice. EGF was administered in doses of 100 μg/kg/day using different schedules. Mucosal damage was assessed. The metaphase arrest method with vinblastine was used to evaluate the diurnal rhythm of mitosis. EGF in regimens employed did not protect the mouse lip epithelial cells from irradiation induced damage, but it has a demonstrable stimulatory effect on cell proliferation in lip mucosa which is dependent on the schedules of administration. The reasons and mechanisms are discussed

  2. Hypothalamic growth hormone releasing factor deficiency following cranial irradiation

    International Nuclear Information System (INIS)

    Ahmed, S.R.; Shalet, S.M.

    1984-01-01

    The effect of synthetic human pancreatic tumour GH releasing factor (hp GRF1-44) on GH release has been studied in 10 patients with radiation-induced GH deficiency and four normal subjects. All 10 patients showed subnormal GH responses to both an ITT (median peak GH 3.2 mU/1) and to arginine stimulation (median peak GH 2.9 mU/1), although the remainder of pituitary function was intact. Following an acute intravenous bolus (100 μg) of hp GRF1-44, there was no GH response in two patients and a subnormal but definite GH response in a further four. The remaining four patients showed a significant GH response (median peak GH level 29 mU/1; range 22-57 mU/1) to hp GRF1-44, similar in magnitude and timing to that seen in th four normals. This strongly suggests that in these four subjects, the discrepancy in GH responses to hp GRF1-44, ITT and to arginine was a result of radiation-induced hypothalamic damage leading to a deficiency of endogenous GRF. The availability of synthetic hp GRF capable of stimulating GH secretion means that the distinction between hypothalamic and pituitary causes of GH deficiency will be of considerable therapeutic importance in the future. (author)

  3. Prenatal exposure to environmental factors and congenital limb defects.

    Science.gov (United States)

    Alexander, Peter G; Clark, Karen L; Tuan, Rocky S

    2016-09-01

    Limb congenital defects afflict approximately 0.6:1000 live births. In addition to genetic factors, prenatal exposure to drugs and environmental toxicants, represents a major contributing factor to limb defects. Examples of well-recognized limb teratogenic agents include thalidomide, warfarin, valproic acid, misoprostol, and phenytoin. While the mechanism by which these agents cause dymorphogenesis is increasingly clear, prediction of the limb teratogenicity of many thousands of as yet uncharacterized environmental factors (pollutants) remains inexact. This is limited by the insufficiencies of currently available models. Specifically, in vivo approaches using guideline animal models have inherently deficient predictive power due to genomic and anatomic differences that complicate mechanistic comparisons. On the other hand, in vitro two-dimensional (2D) cell cultures, while accessible for cellular and molecular experimentation, do not reflect the three-dimensional (3D) morphogenetic events in vivo nor systemic influences. More robust and accessible models based on human cells that accurately replicate specific processes of embryonic limb development are needed to enhance limb teratogenesis prediction and to permit mechanistic analysis of the adverse outcome pathways. Recent advances in elucidating mechanisms of normal development will aid in the development of process-specific 3D cell cultures within specialized bioreactors to support multicellular microtissues or organoid constructs that will lead to increased understanding of cell functions, cell-to-cell signaling, pathway networks, and mechanisms of toxicity. The promise is prompting researchers to look to such 3D microphysiological systems to help sort out complex and often subtle interactions relevant to developmental malformations that would not be evident by standard 2D cell culture testing. Birth Defects Research (Part C) 108:243-273, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. External beam irradiation for choroid metastases: identification of factors predisposing to long-term sequelae

    International Nuclear Information System (INIS)

    Rudoler, Shari B.; Corn, Benjamin W.; Shields, Carol L.; De Potter, Patrick; Hyslop, Terry; Shields, Jerry A.; Curran, Walter J.

    1997-01-01

    Purpose: To improve overall quality of life, palliative treatments should attempt to minimize associated complications while effectively controlling specific symptoms. We reviewed our experience treating posterior uveal metastases with external beam radiotherapy (EBRT) to determine the complication rate and to identify the relationship between patient, tumor, or treatment-related factors and the development of ocular complications. Methods and Materials: 483 consecutive patients (pts) (578 eyes) were diagnosed with intraocular metastatic disease from solid tumors between 1972-1995. Of these, 233 eyes (188 pts) had lesions of the posterior uveal tract and received EBRT. Median follow-up time was 5.8 months (range: 0.7-170.0 months). Follow-up information regarding the development of complications was documented for 230 eyes. Complete EBRT details were available for 189 eyes. Seventy-two percent of the patients received 30.0-40.0 Gy in 2.0-3.0 Gy fractions. Biologically effective dose (BED) was calculated to allow meaningful comparisons between various fractionation regimens and total doses. Concurrent chemotherapy and/or hormonal therapy was used for 101 eyes (44%). Results: Median BED was 61 Gy 3 (range, 6.7-105 Gy 3 ), and 80% of treated eyes received BED 50-70 Gy 3 . EBRT energies included photons (70%), 60 Co (19%), electrons (6%), mixed energies (3%), and orthovoltage (2%). Lens-sparing techniques were used in 136 eyes (71%). At last follow-up 28 eyes (12%) developed one or more significant complications, including cataracts (16 eyes), radiation retinopathy (6 eyes), optic neuropathy (5 eyes), exposure keratopathy (5 eyes), and neovascularization of the iris (4 eyes). Two eyes developed narrow-angle glaucoma, and one of these required enucleation. On univariate analysis, Caucasian race (vs. Black/Hispanic, p = 0.03), increased intraocular pressure at diagnosis (>21 mmHg, p = 0.02), and diagnosis by biopsy (vs. no biopsy, p = 0.03) predisposed toward the

  5. Factors Affecting Detection Of Irradiated Bone Meat By Using Electron Spine Resonance

    International Nuclear Information System (INIS)

    FARAG, S.A.; ATIA, A.I.; HASSAN, G.M.

    2009-01-01

    Different types of bone meats were purchased locally such as camel, cow and sheep. The bones were removed, cleaned and irradiated with gamma rays at different doses (5, 10 and 20 kGy). The bone samples were stored in a refrigerator for five months for studying their stability of radiation-induced free radicals using electron spin resonance (ESR) technique. The effect of thermal treatment at 50 o C at intervals was studied besides effect of storage period and re-irradiation process on ESR signal intensity. The ESR spectrum for radical species in irradiated samples was characterized by signal with spectroscopic splitting factor (g factor) of g1=2.0025 and g2=1.9973 for camel, cow and sheep bones, respectively. The signal at g = 2.0025 was ascribed to free radical rotation CO -2 that was derived from radiation-induced hydroxyapatite. Generally, the results proved that all above mentioned factors under investigation can affect ESR signal intensity but not prevent the recognize of irradiated bones, therefore, it must be taken in mind when calculating the absorbed dose.

  6. Risk factors of conventional irradiation-induced lower cranial neuropathy in patients with nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Pan Jianji; Hong Jinsheng; Zhang Yu

    2006-01-01

    Objective: To study the risk factors of radiation-induced lower cranial neuropathy (RILCN) after conventional radiotherapy in patients with nasopharyngeal carcinoma, and to improve the radiotherapeutic planning. Methods: A hundred cases received radical radiotherapy of nasopharyngeal carcinoma and 200 individual matched controls on sex, age and time to start the radiotherapy were studied. Conditional logistic regression model was used to analyze 13 risk factors related to development of RILCN. Results: Conditional logistic regression analysis revealed that cigarette smoking, irradiation scheme, radiation close to the superior neck, neck fibrosis and acute radiation-related dermatitis of neck were risk factors of RILCN, their relative risks were 4.594, 2.629, 1.072, 4.141 and 2.531, respectively. Among three external irradiation schemes, it is found that pre-auricular portal plus whole neck tangential portal irradiation had the highest risk of RILCN. Conclusions: The study suggested that the irradiation scheme of pre-auricular portal plus whole neck tangential portal should be no longer used. (authors)

  7. Changes in rat plasma fibrinolytic factors during long term follow up after whole body irradiation

    International Nuclear Information System (INIS)

    Dudek-Wojciechowska, G.; Dancewicz, A.M.

    1989-01-01

    Rats were whole body irradiated with a dose of 7.0 Gy and then bled at different times after exposure, from 1 day to 12 months; in their plasma the activity of plasmin, the level of plasminogen, the activity of plasminogen activator as well as α 2 -antiplasmin and α 2 -macroglobulin were determined. In comparison to control values obtained in parallel determinations it was found that during the acute phase of radiation disease (up to 30 days after irradiation) the activity of plasmin and the level of plasminogen underwent fluctuation: at the beginning there was an increase, followed by a decrease at later time intervals. There was also a distinct decrease (over 50%) in the activity of plasminogen activator. During the 2 to 4 weeks after exposure the activity of inhibitors was somewhat decreased, especially that of α 2 -macroglobulin. At later periods the level of plasminogen and the activity of plasminogen activator returned to normal but that of plasmin underwent fluctuation again, reaching a significant decrease in activity 6 and 12 months after exposure. At these time points also some decrease in activity of inhibitors was observed, especially in that of α 2 -macroglobulin. 11 refs., 1 fig., 2 tabs. (author)

  8. Effect of chronic irradiation combined with other damaging factors on some morphological systems of mice

    International Nuclear Information System (INIS)

    Ponomareva, T.V.; Merkushev, G.N.; Pil'shchuk, E.M.; Bikkulov, R.I.

    1978-01-01

    A model experiment on mice is carried out to study morphofunctional changes that occur in mammals chronically exposed to radiation in doses close to those in occupational exposures of a man. Mice have been exposed to gamma-radiation at dose rates of 6, 16, 40, 120, and 300 mr/day from the time of birth onward throughout lifetime. It is concluded that, where a chronic purulent infection is present, chronic irradiation at the above dose rates, with the exception of 6 mr/day, accelerates the onset of irreversible pathologic changes, in particular of amyloidosis, in immunocompetent organs

  9. Urbanization and traffic related exposures as risk factors for Schizophrenia

    DEFF Research Database (Denmark)

    Pedersen, Carsten Bøcker; Mortensen, Preben Bo

    2006-01-01

    to nearest major road had no significant effect. CONCLUSIONS: The cause(s) or exposure(s) responsible for the urban-rural differences in schizophrenia risk were closer related to the degree of urbanization than to the geographical distance to nearest major road. Traffic related exposures might thus be less......BACKGROUND: Urban birth or upbringing increase schizophrenia risk. Though unknown, the causes of these urban-rural differences have been hypothesized to include, e.g., infections, diet, toxic exposures, social class, or an artefact due to selective migration. METHODS: We investigated the hypothesis...... that traffic related exposures affect schizophrenia risk and that this potential effect is responsible for the urban-rural differences. The geographical distance from place of residence to nearest major road was used as a proxy variable for traffic related exposures. We used a large population-based sample...

  10. Effects of neonatal thymic exposure to high doses of X-irradiation

    International Nuclear Information System (INIS)

    Bains, G.S.; Sundaram, K.

    1979-01-01

    The thymic region of neonatal Swiss mice was exposed to doses varying from 1000 R to 2000 R of X-irradiation. The animals did not show any signs of wasting syndrome up to 6 months after irradiation. At this time hyperplasia of the thymus with an associated lymphocytosis was evident in irradiated animals. Antibody production to sheep red blood cells (SRBC) was not affected. However, at 12 months post-irradiation the animals showed signs of wasting disease with a progressive increase in their numbers at 18 and 24 months of age. The percentage incidence of animals with wasting disease was dose dependent. At this stage in the majority of the animals with the disease the thymus showed varying degrees of atrophy along with splenomegaly. There were no significant differences in the number of lymphocytes but the number of granulocytes showed a substantial increase. This was more evident in animals exposed to 2000 R to the thymic region. Though one observed a lowered ability to form antibodies to bovine serum albumin (BSA) with advancing age, the thymic irradiation did not affect the immune response to BSA even in animals manifesting wasting disease. An interesting observation has been the development of a severe loss of muscle power and tone in the hind limbs in a large majority of animals. (author)

  11. Factors Associated With the Development of Breast Cancer-Related Lymphedema After Whole-Breast Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Chirag; Wilkinson, John Ben; Baschnagel, Andrew [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Ghilezan, Mihai [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); William Beaumont School of Medicine, Oakland University, Royal Oak, MI (United States); Riutta, Justin; Dekhne, Nayana; Balaraman, Savitha [Beaumont Cancer Institute, William Beaumont Hospital, Royal Oak, MI (United States); William Beaumont School of Medicine, Oakland University, Royal Oak, MI (United States); Mitchell, Christina; Wallace, Michelle [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Vicini, Frank, E-mail: fvicini@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Beaumont Cancer Institute, William Beaumont Hospital, Royal Oak, MI (United States); William Beaumont School of Medicine, Oakland University, Royal Oak, MI (United States)

    2012-07-15

    Purpose: To determine the rates of breast cancer-related lymphedema (BCRL) in patients undergoing whole-breast irradiation as part of breast-conserving therapy (BCT) and to identify clinical, pathologic, and treatment factors associated with its development. Methods and Materials: A total of 1,861 patients with breast cancer were treated at William Beaumont Hospital with whole-breast irradiation as part of their BCT from January 1980 to February 2006, with 1,497 patients available for analysis. Determination of BCRL was based on clinical assessment. Differences in clinical, pathologic, and treatment characteristics between patients with BCRL and those without BCRL were evaluated, and the actuarial rates of BCRL by regional irradiation technique were determined. Results: The actuarial rate of any BCRL was 7.4% for the entire cohort and 9.9%, 14.7%, and 8.3% for patients receiving a supraclavicular field, posterior axillary boost, and internal mammary irradiation, respectively. BCRL was more likely to develop in patients with advanced nodal status (11.4% vs. 6.3%, p = 0.001), those who had a greater number of lymph nodes removed (14 nodes) (9.5% vs. 6.0%, p = 0.01), those who had extracapsular extension (13.4% vs. 6.9%, p = 0.009), those with Grade II/III disease (10.8% vs. 2.9%, p < 0.001), and those who received adjuvant chemotherapy (10.5% vs. 6.7%, p = 0.02). Regional irradiation showed small increases in the rates of BCRL (p = not significant). Conclusions: These results suggest that clinically detectable BCRL will develop after traditional BCT in up to 10% of patients. High-risk subgroups include patients with advanced nodal status, those with more nodes removed, and those who receive chemotherapy, with patients receiving regional irradiation showing a trend toward increased rates.

  12. Granulocyte colony-stimulating factor and drugs elevating extracellular adenosine synergize to enhance haematopoietic reconstitution in irradiated mice

    Energy Technology Data Exchange (ETDEWEB)

    Pospisil, M.; Hofer, M.; Netikova, J.; Hola, J.; Vacek, A. [Academy of Sciences of the Czech Republic, Inst. of Biophysics, Brno (Czech Republic); Znojil, V.; Vacha, J. [Masaryk Univ., Medical Faculty, Brno (Czech Republic)

    1998-03-01

    The activation of adenosine receptors has recently been demonstrated to stimulate haematopoiesis. In the present study, we investigated the ability of drugs elevating extracellular adenosine to influence curative effects of granulocyte colony-stimulating factor (G-CSF) in mice exposed to a sublethal dose of 4 Gy of {sup 60}Co radiation. Elevation of extracellular adenosine in mice was induced by the combined administration of dipyridamole, a drug inhibiting the cellular uptake of adenosine, and adenosine monophosphate (AMP), an adenosine prodrug. The effects of dipyridamole plus AMP, and G-CSF, administered either alone or in combination, were evaluated. The drugs were injected to mice in a 4-d treatment regimen starting on d 3 after irradiation and the haematopoietic response was evaluated on d 7, 10, 14, 18 and 24 after irradiation. While the effects of G-CSF on the late maturation stages of blood cells, appearing shortly after the completion of the treatment, were not influenced by dipyridamole plus AMP, positive effects of the combination therapy occurred in the post-irradiation recovery phase which is dependent on the repopulation of haematopoietic stem cells. This was indicated by the significant elevation of counts of granulocyte-macrophage progenitor cells (GM-CFC) and granulocytic cells in the bone marrow (d 14), of GM-CFC (d 14), granulocytic and erythroid cells (d 14 and 18) in the spleen, and of neutrophils (d 18), monocytes (d 14 and 18) and platelets (d 18) in the peripheral blood. These effects suggest that the repopulation potential of the combination therapy lies in a common multi-lineage cell population. The results of this study implicate the promising possibility to enhance the curative effects of G-CSF under conditions of myelosuppressive state induced by radiation exposure. (au) 43 refs.

  13. Granulocyte colony-stimulating factor and drugs elevating extracellular adenosine synergize to enhance haematopoietic reconstitution in irradiated mice

    International Nuclear Information System (INIS)

    Pospisil, M.; Hofer, M.; Netikova, J.; Hola, J.; Vacek, A.; Znojil, V.; Vacha, J.

    1998-01-01

    The activation of adenosine receptors has recently been demonstrated to stimulate haematopoiesis. In the present study, we investigated the ability of drugs elevating extracellular adenosine to influence curative effects of granulocyte colony-stimulating factor (G-CSF) in mice exposed to a sublethal dose of 4 Gy of 60 Co radiation. Elevation of extracellular adenosine in mice was induced by the combined administration of dipyridamole, a drug inhibiting the cellular uptake of adenosine, and adenosine monophosphate (AMP), an adenosine prodrug. The effects of dipyridamole plus AMP, and G-CSF, administered either alone or in combination, were evaluated. The drugs were injected to mice in a 4-d treatment regimen starting on d 3 after irradiation and the haematopoietic response was evaluated on d 7, 10, 14, 18 and 24 after irradiation. While the effects of G-CSF on the late maturation stages of blood cells, appearing shortly after the completion of the treatment, were not influenced by dipyridamole plus AMP, positive effects of the combination therapy occurred in the post-irradiation recovery phase which is dependent on the repopulation of haematopoietic stem cells. This was indicated by the significant elevation of counts of granulocyte-macrophage progenitor cells (GM-CFC) and granulocytic cells in the bone marrow (d 14), of GM-CFC (d 14), granulocytic and erythroid cells (d 14 and 18) in the spleen, and of neutrophils (d 18), monocytes (d 14 and 18) and platelets (d 18) in the peripheral blood. These effects suggest that the repopulation potential of the combination therapy lies in a common multi-lineage cell population. The results of this study implicate the promising possibility to enhance the curative effects of G-CSF under conditions of myelosuppressive state induced by radiation exposure. (au)

  14. Quantitative assessment of multi-isocentric radiosurgical irradiation based on the f factor

    International Nuclear Information System (INIS)

    Lefkopoulos, D.; Schlienger, M.; Hancilar, T.; Keraudy, K.; Touboul, E.

    1995-01-01

    To evaluate quantitatively the stereotactic irradiations, we defined a DVH parameter (f) resulting from the lesion underdosage and healthy tissues overdosage curves. The Lesion Underdose Factor (LUF) is the ratio of the lesion volume receiving dose inferior to a reference isodose to the lesion volume. The Healthy Tissue Overdose Factor HTOF quantitates the amount of tissue external to the lesion receiving dose equal to or greater than a given reference isodose relatively to the lesion volume. The LUF and HTOF curves represent the variation of the LUF and HTOF factors as a function of the reference isodose. The f factor is the surface situated below the intersection of the two curves. The optimization goal of the planification procedure could consist in the minimization of f. We have correlated them with clinical results (obliteration of the nidus) of a series of 34 multi-isocenters AVMs linac irradiation. The treatment dose protocol was a peripheral dose of 20 - 25 Gy (50 to 70% isodose range). According to this preliminary study, it seems that f factor provides clinically useful quantitative indices for the treatment plan evaluation. The choice of the optimal treatment plan and reference isodose is realized as follows. For a same patient different treatment plans are calculated by successive modifications of the irradiation parameters, as the number of isocenters, the distances between isocenters, the collimators diameter, the number of arcs and their angular length etc. The choice of optimal treatment plan is based on a clinically validated quantitative factor such as the f factor. According to our preliminary results one should select the treatment plan corresponding to the smallest value of f. The choice of the optimal reference isodose is based on the clinical data (lesion volume and topography, adjacent critical structures) and the LUF and HTOF factors following a well-defined protocol

  15. Activation of chromatin degradation by a protein factor of thymocyte cytoplasm of irradiated mice

    International Nuclear Information System (INIS)

    Soldatenkov, V.A.; Filippovich, I.V.

    1986-01-01

    A cytoplasmic thymocyte fraction isolated 1 h after irradiation of mice accelerates chromatin degradation in isolated nuclei. Treatment of the cytoplasmic fraction by heat and injection of cycloheximide to mice prevent the acceleration of DNA degradation. The analysis of the chromatin degradation products and the kinetics of this process at acid and alkaline pH shows that activation of DNA degradation in thymocytes by a factor obtained from the irradiated cell cytoplasm is specific for a Ca 2+ , Mg 2+ -dependent enzyme. The time- and dose-dependent parameters of the appearance in the thymocyte cytoplasm of the factor influencing degradation of chromatin are in a good agreement with both the time of the onset of its postirradiation degradation and the dose dependence of this process

  16. Indoor Air Pollutant Exposure for Life Cycle Assessment: Regional Health Impact Factors for Households

    DEFF Research Database (Denmark)

    Rosenbaum, Ralph K.; Meijer, Arjen; Demou, Evangelia

    2015-01-01

    of magnitude, due to the variability of ventilation rate, building occupation, and volume. To compare health impacts as a result of indoor exposure with those from outdoor exposure, the indoor exposure characterization factors determined with the modified USEtox model were applied in a case study on cooking...

  17. Radiodiagnostics of kidneys and urinary passages - exposure to irradiation in children

    International Nuclear Information System (INIS)

    Renner, J.

    1979-01-01

    By means of thermoluminescencedosimetry the irradiation dose for the gonads was measured with LiF dosimeters in children who where subjected to infusion urograms or micturitioncystourethrograms. The dose to which the male patients were exposed was measured near the scrotum at the thigh; the dose received by the female patients was measured in the rectum. (DG) [de

  18. Solar UV radiation exposure of seamen - Measurements, calibration and model calculations of erythemal irradiance along ship routes

    Energy Technology Data Exchange (ETDEWEB)

    Feister, Uwe [German Meteorological Service, Meteorological Observatory Lindenberg - Richard-Assmann-Observatory, Am Observatorium 12, 15848 Lindenberg (Germany); Meyer, Gabriele; Kirst, Ulrich [German Social Accident Insurance Institution for Transport and Traffic, Ottenser Hauptstrasse 54, 22765 Hamburg (Germany)

    2013-05-10

    Seamen working on vessels that go along tropical and subtropical routes are at risk to receive high doses of solar erythemal radiation. Due to small solar zenith angles and low ozone values, UV index and erythemal dose are much higher than at mid-and high latitudes. UV index values at tropical and subtropical Oceans can exceed UVI = 20, which is more than double of typical mid-latitude UV index values. Daily erythemal dose can exceed the 30-fold of typical midlatitude winter values. Measurements of erythemal exposure of different body parts on seamen have been performed along 4 routes of merchant vessels. The data base has been extended by two years of continuous solar irradiance measurements taken on the mast top of RV METEOR. Radiative transfer model calculations for clear sky along the ship routes have been performed that use satellite-based input for ozone and aerosols to provide maximum erythemal irradiance and dose. The whole data base is intended to be used to derive individual erythemal exposure of seamen during work-time.

  19. Promotive effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on recovery from neutropenia induced by fractionated irradiation in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kabaya, Koji; Watanabe, Masahiko; Kusaka, Masaru; Seki, Masatoshi (Kirin Brewery Co., Ltd., Gunma (Japan). Pharmaceutical Research Laboratory); Fushiki, Masato

    1994-08-01

    The effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on the recovery from neutropenia induced by fractionated whole-body irradiation was investigated in mice. Male 7-week old C3H/HeN mice received a total of ten exposures of 0.25 Gy/day from day 1 to 5 and from day 8 to 12. Peripheral neutropenia with a nadir on day 17 was caused by the fractionated irradiation. Daily subcutaneous injections of rhG-CSF at 0.25 and 2.5 [mu]g/body/day from day from day 1 to 21 promoted the recovery of neutrophils in a dose-dependent manner. The kinetics of morphologically identifiable bone marrow cells were studied to clarify the mechanism behind the promotive effect of this factor. A slight decrease in mitotic immature granulocytes, such as myeloblasts, promyelocytes and myelocytes on day 5, and a drastic decrease in metamyelocytes and marrow neutrophils on days 5, 9, and 17 were seen in the femur of irradiated mice. Treatment using rhG-CSF caused an increase in immature granulocytes of all differential stages in the femur. Microscopic findings of the femurs and spleens also reveals an increase in immature granulocytes in these organs in mice injected with rhG-CSF. These results indicate that rhG-CSF accelerates granulopoiesis in the femur and spleen, thereby promoting recovery from neutropenia induced by fractionated irradiation. (author).

  20. Promotive effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on recovery from neutropenia induced by fractionated irradiation in mice

    International Nuclear Information System (INIS)

    Kabaya, Koji; Watanabe, Masahiko; Kusaka, Masaru; Seki, Masatoshi; Fushiki, Masato.

    1994-01-01

    The effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on the recovery from neutropenia induced by fractionated whole-body irradiation was investigated in mice. Male 7-week old C3H/HeN mice received a total of ten exposures of 0.25 Gy/day from day 1 to 5 and from day 8 to 12. Peripheral neutropenia with a nadir on day 17 was caused by the fractionated irradiation. Daily subcutaneous injections of rhG-CSF at 0.25 and 2.5 μg/body/day from day from day 1 to 21 promoted the recovery of neutrophils in a dose-dependent manner. The kinetics of morphologically identifiable bone marrow cells were studied to clarify the mechanism behind the promotive effect of this factor. A slight decrease in mitotic immature granulocytes, such as myeloblasts, promyelocytes and myelocytes on day 5, and a drastic decrease in metamyelocytes and marrow neutrophils on days 5, 9, and 17 were seen in the femur of irradiated mice. Treatment using rhG-CSF caused an increase in immature granulocytes of all differential stages in the femur. Microscopic findings of the femurs and spleens also reveals an increase in immature granulocytes in these organs in mice injected with rhG-CSF. These results indicate that rhG-CSF accelerates granulopoiesis in the femur and spleen, thereby promoting recovery from neutropenia induced by fractionated irradiation. (author)

  1. Ozone and ultraviolet-B irradiances: experimental determination of the radiation amplification factor

    International Nuclear Information System (INIS)

    Blumthaler, M.; Salzgeber, M.; Ambach, W.

    1995-01-01

    During the period 1981-1993, measurements of solar UV irradiances were made at the High-Alpine Research Station Jungfraujoch (Switzerland, 3576 m a.s.l.) to determine the radiation amplification factor (RAF) for the Robertson-Berger sunburn meter and for the narrow-band wavelength ranges of the Eppley filter spectrometer. The Robertson-Berger sunburn meter model 500 showed a RAF of 1.07 ± 0.15 at solar elevations between 20 o and 60 o . The RAF for human erythema is 1.1 in comparison. Therefore the Robertson-Berger sunburn meter is suitable to measure the influence of total atmospheric ozone variations on the effective erythemal irradiance. In the narrow-band wavelength ranges of the Eppley filter spectrometer the RAF increases greatly at shorter wavelengths with RAF of 1.06, 1.40 and 2.35 for the optical centers 315.1 nm, 311.1 nm and 305.2 nm, evaluated at 30 o solar elevation. In order to minimize perturbations by aerosol optical depth and albedo in the evaluation of the RAF the ratios of UV irradiances to total irradiances were evaluated. (Author)

  2. Revisiting Biomarkers of Total-Body and Partial-Body Exposure in a Baboon Model of Irradiation.

    Directory of Open Access Journals (Sweden)

    Marco Valente

    Full Text Available In case of a mass casualty radiation event, there is a need to distinguish total-body irradiation (TBI and partial-body irradiation (PBI to concentrate overwhelmed medical resources to the individuals that would develop an acute radiation syndrome (ARS and need hematologic support (i.e., mostly TBI victims. To improve the identification and medical care of TBI versus PBI individuals, reliable biomarkers of exposure could be very useful. To investigate this issue, pairs of baboons (n = 18 were exposed to different situations of TBI and PBI corresponding to an equivalent of either 5 Gy 60Co gamma irradiation (5 Gy TBI; 7.5 Gy left hemibody/2.5 right hemibody TBI; 5.55 Gy 90% PBI; 6.25 Gy 80% PBI; 10 Gy 50% PBI, 15 Gy 30% PBI or 2.5 Gy (2.5 Gy TBI; 5 Gy 50% PBI. More than fifty parameters were evaluated before and after irradiation at several time points up to 200 days. A partial least square discriminant analysis showed a good distinction of TBI from PBI situations that were equivalent to 5 Gy. Furthermore, all the animals were pooled in two groups, TBI (n = 6 and PBI (n = 12, for comparison using a logistic regression and a non parametric statistical test. Nine plasmatic biochemical markers and most of hematological parameters turned out to discriminate between TBI and PBI animals during the prodromal phase and the manifest illness phase. The most significant biomarkers were aspartate aminotransferase, creatine kinase, lactico dehydrogenase, urea, Flt3-ligand, iron, C-reactive protein, absolute neutrophil count and neutrophil-to-lymphocyte ratio for the early period, and Flt3-ligand, iron, platelet count, hemoglobin, monocyte count, absolute neutrophil count and neutrophil-to-lymphocyte ratio for the ARS phase. These results suggest that heterogeneity could be distinguished within a range of 2.5 to 5 Gy TBI.

  3. Epidermal growth factor receptor: an independent predictor of survival in astrocytic tumors given definitive irradiation

    International Nuclear Information System (INIS)

    An Zhu; Shaeffer, James; Leslie, Susan; Kolm, Paul; El-Mahdi, Anas M.

    1996-01-01

    Purpose: To determine whether the expression of epidermal growth factor receptor (EGFR) protein was predictive of patient survival independently of other prognostic factors in astrocytic tumors. Methods and Materials: Epidermal growth factor receptor protein expression was investigated immunohistochemically in formalin-fixed, paraffin-embedded surgical specimens of 55 glioblastoma multiforme, 14 anaplastic astrocytoma, and 2 astrocytomas given definitive irradiation. We evaluated the relationship of EGFR protein expression and tumor grade, histologic features, age at diagnosis, sex, patient survival, and recurrence-free survival. Results: The percentage of tumor cells which were EGFR positive related to reduced survival by Cox regression analysis in both univariate (p = 0.0424) and multivariate analysis (p = 0.0016). Epidermal growth factor receptor positivity was the only 1 of 11 clinical and histological variables associated with decreased recurrence-free survival by either univariate (p = 0.0353) or multivariate (p = 0.0182) analysis. Epidermal growth factor receptor protein expression was not related to patient age, sex, or histologic features. Conclusion: Epidermal growth factor receptor positivity was a significant and independent prognostic indicator for overall survival and recurrence-free survival for irradiated patients with astrocytic gliomas

  4. Effects of irradiation on the production of factors regulating humoral hematopoiesis

    International Nuclear Information System (INIS)

    Seki, Masatoshi; Yoshida, Kazuko

    1974-01-01

    Changes in factors regulating humoral hematopoiesis after irradiation were studied by intraperitoneal insertion of cellulose acetate membrane (CA membrane). There is little possibility that regulation factors is produced by macrophage itself. The growth of the colony depends mainly on increase or decrease of regulation factors in the host. However, there is a possibility that the macrophage interferes the action of these regulation factors. From the fact that there is no action of EPO (erythropoiesis) in Sl/slsup(d) mice having abnormal function of microenvironment, it is suggested that the action of EPO is brought about through the function of the microenvironment. In the analysis of the colony formation by intraperitoneal insertion of CA membrane, it is considered that the erythroblastic colony can be formed by the macrophage through the action of EPO. In short, it is concluded that factors regulating humoral hematopoiesis increased in the body of the mouse which have been irradiated to the whole body, and the increase in these factors is not constant, but remarkably changes with time. (Namekawa, K.)

  5. Calculation of dose conversion factors for doses in the fingernails to organ doses at external gamma irradiation in air

    International Nuclear Information System (INIS)

    Khailov, A.M.; Ivannikov, A.I.; Skvortsov, V.G.; Stepanenko, V.F.; Orlenko, S.P.; Flood, A.B.; Williams, B.B.; Swartz, H.M.

    2015-01-01

    Absorbed doses to fingernails and organs were calculated for a set of homogenous external gamma-ray irradiation geometries in air. The doses were obtained by stochastic modeling of the ionizing particle transport (Monte Carlo method) for a mathematical human phantom with arms and hands placed loosely along the sides of the body. The resulting dose conversion factors for absorbed doses in fingernails can be used to assess the dose distribution and magnitude in practical dose reconstruction problems. For purposes of estimating dose in a large population exposed to radiation in order to triage people for treatment of acute radiation syndrome, the calculated data for a range of energies having a width of from 0.05 to 3.5 MeV were used to convert absorbed doses in fingernails to corresponding doses in organs and the whole body as well as the effective dose. Doses were assessed based on assumed rates of radioactive fallout at different time periods following a nuclear explosion. - Highlights: • Elemental composition and density of nails were determined. • MIRD-type mathematical human phantom with arms and hands was created. • Organ doses and doses to nails were calculated for external photon exposure in air. • Effective dose and nail doses values are close for rotational and soil surface exposures.

  6. The value of prognostic factors for uterine cervical cancer patients treated with irradiation alone

    International Nuclear Information System (INIS)

    Grigienė, Rūta; Valuckas, Konstantinas P; Aleknavičius, Eduardas; Kurtinaitis, Juozas; Letautienė, Simona R

    2007-01-01

    The aim of our study was to investigate and evaluate the prognostic value of and correlations between preclinical and clinical factors such as the stage of the disease, blood Hb level before treatment, size of cervix and lymph nodes evaluated by CT, age, dose of irradiation and duration of radiotherapy related to overall survival, disease-free survival, local control and metastases-free survival in cervical cancer patients receiving radiotherapy alone. 162 patients with International Federation of Gynecology and Obstetrics (FIGO) stage IIA-IIIB cervical carcinoma treated with irradiation were analysed. Univariate and multivariate analyses using the Cox regression model were performed to determine statistical significance of some tumor-related factors. The Hb level before treatment showed significant influence on overall survival (p = 0.001), desease free survival (p = 0.040) and local control (p = 0.038). The lymph node status (>10 mm) assessed on CT had impact on overall survival (p = 0,030) and local control (p = 0,036). The dose at point A had impact on disease free survival (p = 0,028) and local control (p = 0,021) and the radiotherapy duration had showed significant influence on overall survival (p = 0,045), disease free survival (p = 0,006) and local control (p = 0,033). Anemia is a significant and independent prognostic factor of overall survival, disease-free survival and local control in cervical cancer patients treated with irradiation. The size of lymph nodes in CT is an independent prognostic factor for overall survival and local control in cervical cancer patients. The size of cervix uteri evaluated by CT has no prognostic significance in cervical cancer patients treated with radiotherapy. The prognostic value of FIGO stage of cervical cancer is influenced by other factors, analyzed in this study and is not an independent prognostic factor

  7. Lung autophagic response following exposure of mice to whole body irradiation, with and without amifostine

    International Nuclear Information System (INIS)

    Zois, Christos E.; Giatromanolaki, Alexandra; Kainulainen, Heikki; Botaitis, Sotirios; Torvinen, Sira; Simopoulos, Constantinos; Kortsaris, Alexandros; Sivridis, Efthimios; Koukourakis, Michael I.

    2011-01-01

    Research highlights: → We investigated the effect 6 Gy of WBI on the autophagic machinery of normal mouse lung. → Irradiation induces dysfunction of the autophagic machinery in normal lung, characterized by decreased transcription of the LC3A/Beclin-1 mRNA and accumulation of the LC3A, and p62 proteins. → The membrane bound LC3A-II protein levels increased in the cytosolic fraction (not in the pellet), contrasting the patterns noted after starvation-induced autophagy. → Administration of amifostine, reversed all the LC3A and p62 findings, suggesting protection of the normal autophagic function. -- Abstract: Purpose: The effect of ionizing irradiation on the autophagic response of normal tissues is largely unexplored. Abnormal autophagic function may interfere the protein quality control leading to cell degeneration and dysfunction. This study investigates its effect on the autophagic machinery of normal mouse lung. Methods and materials: Mice were exposed to 6 Gy of whole body γ-radiation and sacrificed at various time points. The expression of MAP1LC3A/LC3A/Atg8, beclin-1, p62/sequestosome-1 and of the Bnip3 proteins was analyzed. Results: Following irradiation, the LC3A-I and LC3A-II protein levels increased significantly at 72 h and 7 days. Strikingly, LC3A-II protein was increased (5.6-fold at 7 days; p < 0.001) only in the cytosolic fraction, but remained unchanged in the membrane fraction. The p62 protein, was significantly increased in both supernatant and pellet fraction (p < 0.001), suggesting an autophagosome turnover deregulation. These findings contrast the patterns of starvation-induced autophagy up-regulation. Beclin-1 levels remained unchanged. The Bnip3 protein was significantly increased at 8 h, but it sharply decreased at 72 h (p < 0.05). Administration of amifostine (200 mg/kg), 30 min before irradiation, reversed all the LC3A and p62 findings on blots, suggesting restoration of the normal autophagic function. The LC3A and Beclin1 m

  8. Production of humoral factors that stimulate spleen colony-forming units in mice irradiated with moderate doses of X rays

    International Nuclear Information System (INIS)

    Grande, T.; Gonzalez, J.; Tejero, C.; Maganto, G.; Bueren, J.A.

    1990-01-01

    The production of humoral factors that stimulate spleen colony-forming units (CFU-S) has been studied in irradiated mice using an in vivo diffusion chamber assay. The experiments show that a significant release of factors that stimulate CFU-S takes place in the first few days after irradiation with moderate doses of 1.5 or 5 Gy. In contrast, the release of significant amounts of these humoral factors was not seen in animals irradiated with either low (0.75 Gy) or high (10 Gy) doses of X rays. The correlation observed between the production of factors that stimulate the CFU-S and the hemopoietic regeneration kinetics of the irradiated mice suggests that these factors represent part of the physiological regulators controlling the proliferation of CFU-S

  9. Studying of some physical properties for natural polymers (hemoglobin) for cancer patients before and after exposure to gamma irradiation

    International Nuclear Information System (INIS)

    Farooh, H.A.A.

    2010-01-01

    The effect of radiotherapy on hemoglobin (Hb) polymer, obtained from patients (cases) before and after two periods of local gamma irradiation was studied. The results were compared with healthy volunteer. The patients were classified into two main groups. The first group represents cases that suffer from breast cancer, while, the second group represents cases that suffer from pelvic cancer. The total doses for breast cancer were ranged from 45 to 50 Gy, divided into 25 fractions for 5 weeks. While the total doses for pelvic irradiation were ranged from 20 to 66 Gy; divided into 10-25 fraction for 2-5 weeks. The physical properties of Hb have been studied via several characterization techniques, such as X-ray diffraction, viscosity, Fourier Transform Infra-red spectroscopy (FTIR), Electron Spin Resonance (ESR) and UV-visible spectra. The resultant effects of radiotherapy can be summarized as follows: X-ray diffraction pattern of Hb polymer, for control and cancer breast before and after exposure to accumulated gamma irradiation, were characterized by halo consisting of two adjacent peaks with maximum intensity observed at 2θ = 9.549 and 21.222, respectively. By increasing the gamma doses, a decrease in crystalline phase (disordering character) were obtained. Also, the halos width at half of maximal intensity (δW) shows a decrease followed by an increase with increasing the accumulative gamma dose up to 50 Gy, but still below + ve and -ve control values. The viscosity were measured for Hb solutions of concentration 4.1x10 -5 Mol on the base of heme-heme interaction and at different shear rates (10-400 sec -1 ). The plastic viscosity for every hemoglobin samples was calculated by Bingham equation using specific software of the viscometer. There was an increase in the plastic viscosity of Hb cancer patients compared to -ve control. On irradiation the viscosity shows an increase with increasing the accumulative gamma dose. Fourier transform infra-red spectra (FTIR

  10. Possible nature and specificity of a protein factor favoringsolubilization of chromatin from irradiated animal thymocytes

    International Nuclear Information System (INIS)

    Soldatenkov, V.A.; Trebenok, Z.A.; Filippovich, I.V.

    1989-01-01

    It is shown that activation of endonucleolysis of thymocyte nuclear chromatin by protein factor from the cells of irradiated animals is not conditioned by its nuclease activity or ability to activate Ca 2+ , Mg 2+ - dependent lymphocyte endonuclease. DNA degradation character and kinetics of accumulation of the forming products doesn't change in autolysis of thymocyte nucleus. It is assumed that protein factor doesn't participate in starting mechanisms of postirradiation chromatin degradation but can be of significance at delayed stages of the process. The discovered effect is characterized by tissue and specific characteristic

  11. Neutron-exposure parameters for the fourth HSST series of metallurgical irradiation capsules

    International Nuclear Information System (INIS)

    Kam, F.B.K.; Stallmann, F.W.; Baldwin, C.A.; Fabry, A.

    1982-01-01

    The neutron exposure parameters for the Heavy Section Steel Technology (HSST) Experiments performed at the Oak Ridge National Laboratory (ORNL) can be determined conservatively to +-10% (1sigma) variance. The neutron exposure parameters used for this study were fluence greater than 1 MeV, fluence greater than 0.1 MeV, and displacements per atom (dpa). Measured reaction rates, calculated neutron transport fluxes, and cross sections values were combined in the logarithmic least square adjustment code LSL

  12. Regularity of mortality and life span of the experimental animals under the exposure of protracted internal irradiation with radionuclides of 137Cs and 90Sr

    International Nuclear Information System (INIS)

    Yindik, V.M.; Serkyiz, Ya.Yi.; Lips'ka, A.Yi.; Alyistratov, O.V.; Drozd, Yi.P.; Gerasimova, T.B.; Dudchenko, T.M.

    2002-01-01

    It has been shown that exposure to protracted low intense irradiation with low doses, caused by radionuclides ( 137 Cs and 90 Sr) has negative influence on survival indices and expected life span in different groups according to age. Mortality of irradiated animals is mainly caused by development of pathological processes of tumor origin. The frequency of radiation induced tumors is the same with intact control

  13. Gamma irradiation does not induce detectable changes in DNA methylation directly following exposure of human cells.

    Directory of Open Access Journals (Sweden)

    Christoph Lahtz

    Full Text Available Environmental chemicals and radiation have often been implicated in producing alterations of the epigenome thus potentially contributing to cancer and other diseases. Ionizing radiation, released during accidents at nuclear power plants or after atomic bomb explosions, is a potentially serious health threat for the exposed human population. This type of high-energy radiation causes DNA damage including single- and double-strand breaks and induces chromosomal rearrangements and mutations, but it is not known if ionizing radiation directly induces changes in the epigenome of irradiated cells. We treated normal human fibroblasts and normal human bronchial epithelial cells with different doses of γ-radiation emitted from a cesium 137 ((137Cs radiation source. After a seven-day recovery period, we analyzed global DNA methylation patterns in the irradiated and control cells using the methylated-CpG island recovery assay (MIRA in combination with high-resolution microarrays. Bioinformatics analysis revealed only a small number of potential methylation changes with low fold-difference ratios in the irradiated cells. These minor methylation differences seen on the microarrays could not be verified by COBRA (combined bisulfite restriction analysis or bisulfite sequencing of selected target loci. Our study shows that acute γ-radiation treatment of two types of human cells had no appreciable direct effect on DNA cytosine methylation patterns in exposed cells.

  14. A study of energy and effective atomic number dependence of the exposure build-up factors in biological samples

    International Nuclear Information System (INIS)

    Sidhu, G.S.; Singh, P.S.; Mudahar, G.S.

    2000-01-01

    A theoretical method is presented to determine the gamma-radiation build-up factors in various biological materials. The gamma energy range is 0.015-15.0 MeV, with penetration depths up to 40 mean free paths considered. The dependence of the exposure build-up factor on incident photon energy and the effective atomic number (Z eff ) has also been assessed. In a practical analysis of dose burden to gamma-irradiated biological materials, the sophistication of Monte Carlo computer techniques would be applied, with associated detailed modelling. However, a feature of the theoretical method presented is its ability to make the consequences of the physics of the scattering process in biological materials more transparent. In addition, it can be quickly employed to give a first-pass dose estimate prior to a more detailed computer study. (author)

  15. 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)

  16. Measuring method for effective neutron multiplication factor upon containing irradiated fuel assembly

    International Nuclear Information System (INIS)

    Ueda, Makoto; Mitsuhashi, Ishi; Sasaki, Tomoharu.

    1993-01-01

    A portion of irradiated fuel assemblies at a place where a reactivity effect is high, that is, at a place where neutron importance is high is replaced with standard fuel assemblies having a known composition to measure neutron fluxes at each of the places. An effective composition at the periphery of the standard fuel assemblies is determined by utilizing a calibration curve determined separately based on the composition and neutron flux values of the standard assemblies. By using the calibration curve determined separately based on this composition and the known composition of the standard fuel assemblies, an effective neutron multiplication factor for the fuel containing portion containing the irradiated fuel assemblies is recognized. Then, subcriticality is ensured and critical safety upon containing the fuel assemblies can be secured quantitatively. (N.H.)

  17. Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

    Energy Technology Data Exchange (ETDEWEB)

    Kovalchuk, O.; Kovalchuk, I.; Hohn, B. [Friedrich Miescher Institute, P.O. Box 2543, CH-4002 Basel (Switzerland); Arkhipov, A. [Chernobyl Scientific and Technical Center of International Research, Shkolnaya Str. 6, 255620 Chernobyl (Ukraine); Barylyak, I.; Karachov, I. [Ukrainian Scientific Genetics Center, Popudrenko Str. 50, 253660 Kiev (Ukraine); Titov, V. [Ivano-Frankivsk State Medical Academy, Galitska Str.2, 284000 Ivano-Frankivsk (Ukraine)

    2000-04-03

    different chemical composition, but equal radioactivity, exhibited different levels of HR, dependent upon the absorbed dose of radiation. Remarkably, we observed a much higher frequency of HR in plants exposed to chronic irradiation when compared to acutely irradiated plants. Although acute application of 0.1-0.5 Gy did not lead to an increase of frequency of HR, the chronic exposure of the plants to several orders of magnitude lower dose of 200 {mu}Gy led to a 5-6-fold induction of the frequency of HR as compared to the control.

  18. Urbanization and traffic related exposures as risk factors for Schizophrenia

    DEFF Research Database (Denmark)

    Pedersen, Carsten Bøcker; Mortensen, Preben Bo

    2006-01-01

    : The geographical distance from place of residence to nearest major road had a significant effect. The highest risk was found in children living 500-1000 metres from nearest major road (RR=1.30 (95% Confidence Interval: 1.17-1.44). However, when we accounted for the degree of urbanization, the geographical distance...... that traffic related exposures affect schizophrenia risk and that this potential effect is responsible for the urban-rural differences. The geographical distance from place of residence to nearest major road was used as a proxy variable for traffic related exposures. We used a large population-based sample......BACKGROUND: Urban birth or upbringing increase schizophrenia risk. Though unknown, the causes of these urban-rural differences have been hypothesized to include, e.g., infections, diet, toxic exposures, social class, or an artefact due to selective migration. METHODS: We investigated the hypothesis...

  19. Acute non-stochastic effect of very low dose whole-body exposure, a thymidine equivalent serum factor

    International Nuclear Information System (INIS)

    Feinendegen, L.E.; Muehlensiepen, H.; Porschen, W.; Booz, J.

    1982-01-01

    Whole-body irradiation of mice causes the dose-dependent appearance of a humoral factor in blood serum which inhibits incorporation of 125-IUdR into tissue culture cells. This factor appears even at doses below 0.01 Gy gamma irradiation and thus is probably not related to cell death. Data are presented relating this humoral factor to thymidine. Since at low doses the target size for this effect was calculated to be the entire cell, a cellular effect is postulated linking the site of few primary absorption events, anywhere in the cell, with the cellular membrane, thus causing changes in membrane charge, structure and/or fluidity. This may lead to blocking thymidine acceptance by the cell, and thus would cause a pile-up of thymidine in the reutilization pathway in peripheral blood and would give rise to the observed effect. The effect appears as a temporary disturbance of the physiological equilibrium and should not be related at present to any cellular damage. The acute low-dose effect described has implications for the measurement of low-dose exposure by biological dosimeters and on basic research on membrane function. (author)

  20. Phototoxicity and oxidative stress responses in Daphnia magna under exposure to sulfathiazole and environmental level ultraviolet B irradiation

    International Nuclear Information System (INIS)

    Kim, Jungkon; Park, Yena; Choi, Kyungho

    2009-01-01

    Sulfonamide antibiotics frequently occur in aquatic environments. In this study, phototoxicity of sulfathiazole (STZ) and its mechanism of action were investigated using Daphnia magna. We evaluated the changes of molecular level stress responses by assessing gene expression, enzyme induction and lipid peroxidation, and the related organism-level effects in D. magna. In the presence of ultraviolet B (UV-B) light (continuous irradiation with 13.8 ± 1.0 μW cm -2 d -1 ), STZ (at the nominal concentration of 94.9 mg/L) caused a significant increase in reactive oxygen species (ROS) generation and lipid peroxidation. Catalase (CAT) and glutathione S-transferase (GST) showed concentration-dependent increases caused by the exposure. Exposure to STZ and UV-B light caused apparent up-regulation of α-esterase, hemoglobin, and vitellogenin mRNA. The survival of daphnids was significantly affected by the co-exposure to STZ and UV-B. The biochemical and molecular level observations in combination with organism-level effects suggest that the phototoxicity of STZ was mediated in part by ROS generated by oxidative stress in D. magna

  1. Phototoxicity and oxidative stress responses in Daphnia magna under exposure to sulfathiazole and environmental level ultraviolet B irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jungkon [School of Public Health, Seoul National University, Seoul, 110-799 (Korea, Republic of)], E-mail: koguma@snu.ac.kr; Park, Yena [School of Public Health, Seoul National University, Seoul, 110-799 (Korea, Republic of)], E-mail: elohim@snu.ac.kr; Choi, Kyungho [School of Public Health, Seoul National University, Seoul, 110-799 (Korea, Republic of)], E-mail: kyungho@snu.ac.kr

    2009-01-18

    Sulfonamide antibiotics frequently occur in aquatic environments. In this study, phototoxicity of sulfathiazole (STZ) and its mechanism of action were investigated using Daphnia magna. We evaluated the changes of molecular level stress responses by assessing gene expression, enzyme induction and lipid peroxidation, and the related organism-level effects in D. magna. In the presence of ultraviolet B (UV-B) light (continuous irradiation with 13.8 {+-} 1.0 {mu}W cm{sup -2} d{sup -1}), STZ (at the nominal concentration of 94.9 mg/L) caused a significant increase in reactive oxygen species (ROS) generation and lipid peroxidation. Catalase (CAT) and glutathione S-transferase (GST) showed concentration-dependent increases caused by the exposure. Exposure to STZ and UV-B light caused apparent up-regulation of {alpha}-esterase, hemoglobin, and vitellogenin mRNA. The survival of daphnids was significantly affected by the co-exposure to STZ and UV-B. The biochemical and molecular level observations in combination with organism-level effects suggest that the phototoxicity of STZ was mediated in part by ROS generated by oxidative stress in D. magna.

  2. Prognostic factors for outcomes after whole-brain irradiation of brain metastases from relatively radioresistant tumors: a retrospective analysis

    NARCIS (Netherlands)

    Meyners, T.; Heisterkamp, C.; Kueter, J.D.; Veninga, T.; Stalpers, L.J.A.; Schild, S.E.; Rades, D.

    2010-01-01

    Background: This study investigated potential prognostic factors in patients treated with whole-brain irradiation (WBI) alone for brain metastases from relatively radioresistant tumors such as malignant melanoma, renal cell carcinoma, and colorectal cancer. Additionally, a potential benefit from

  3. Prognostic factors for outcomes after whole-brain irradiation of brain metastases from relatively radioresistant tumors: a retrospective analysis

    NARCIS (Netherlands)

    Meyners, Thekla; Heisterkamp, Christine; Kueter, Jan-Dirk; Veninga, Theo; Stalpers, Lukas J. A.; Schild, Steven E.; Rades, Dirk

    2010-01-01

    This study investigated potential prognostic factors in patients treated with whole-brain irradiation (WBI) alone for brain metastases from relatively radioresistant tumors such as malignant melanoma, renal cell carcinoma, and colorectal cancer. Additionally, a potential benefit from escalating the

  4. Adolescent Weight Preoccupation: Influencing Factors and Entertainment Media Exposure

    Science.gov (United States)

    Jacob, John; Yoo, Jeong-Ju

    2010-01-01

    This study examined how boys' and girls' weight preoccupation varied by grade level, parent-child relationships, self-classified weight, entertainment media exposure levels, and gender. Seventh-grade girls (n = 190) and boys (n = 132) and 10th-grade girls (n = 99) and boys (n = 67) participated. Girls were more likely to report weight…

  5. Dentinal temperature transients caused by exposure to CO2 laser irradiation and possible pulpal damage.

    Science.gov (United States)

    Jeffrey, I W; Lawrenson, B; Saunders, E M; Longbottom, C

    1990-02-01

    An investigation is described that attempts to establish, in vitro, the characteristics of heat transference following laser irradiation of bovine dentinal tissue and the relationship with the periodicity of radiation. The results of this study appear to indicate that at depths of overlying dentine of up to 3 mm, laser-induced thermal injury to the pulp is a definite possibility. Fail-safe facilities to prevent build up of heat must be incorporated into the design of dental lasers to allow their beneficial effects to be utilized without the risk of iatrogenic damage.

  6. Radiation exposure during in-vivo analysis of human dental enamel by proton irradiation

    International Nuclear Information System (INIS)

    Baijot-Stroobants, J.; Bodart, F.; Deconninck, G.; Vreven, J.

    Fluorine can be analysed by proton activation, with detection of prompt γ-rays. Using external beams, it is possible to make in-vivo determinations and to follow the concentration in fluoridated enamel. Radiation damage and radiation hazards are investigated. It is found that the dose rate is very small and that the technique can be used without radiation problems. Local destruction on the enamel surface is investigated using a scanning microscope, no modification is observed in the cristallite structure after irradiation. (author)

  7. Impact of Age and Insulin-Like Growth Factor-1 on DNA Damage Responses in UV-Irradiated Human Skin.

    Science.gov (United States)

    Kemp, Michael G; Spandau, Dan F; Travers, Jeffrey B

    2017-02-26

    The growing incidence of non-melanoma skin cancer (NMSC) necessitates a thorough understanding of its primary risk factors, which include exposure to ultraviolet (UV) wavelengths of sunlight and age. Whereas UV radiation (UVR) has long been known to generate photoproducts in genomic DNA that promote genetic mutations that drive skin carcinogenesis, the mechanism by which age contributes to disease pathogenesis is less understood and has not been sufficiently studied. In this review, we highlight studies that have considered age as a variable in examining DNA damage responses in UV-irradiated skin and then discuss emerging evidence that the reduced production of insulin-like growth factor-1 (IGF-1) by senescent fibroblasts in the dermis of geriatric skin creates an environment that negatively impacts how epidermal keratinocytes respond to UVR-induced DNA damage. In particular, recent data suggest that two principle components of the cellular response to DNA damage, including nucleotide excision repair and DNA damage checkpoint signaling, are both partially defective in keratinocytes with inactive IGF-1 receptors. Overcoming these tumor-promoting conditions in aged skin may therefore provide a way to lower aging-associated skin cancer risk, and thus we will consider how dermal wounding and related clinical interventions may work to rejuvenate the skin, re-activate IGF-1 signaling, and prevent the initiation of NMSC.

  8. Apoptosis in chronic myeloid leukaemia: normal responses by progenitor cells to growth factor deprivation, X-irradiation and glucocorticoids

    Energy Technology Data Exchange (ETDEWEB)

    Amos, T.A.S.; Lewis, J.L.; Grand, F.H.; Gooding, R.P.; Goldman, J.M.; Gordon, M.Y. [Royal Postgraduate Medical School, London (United Kingdom)

    1995-10-01

    Inhibition of apoptosis (genetically programmed active cell death) by p210 BCR-ABL expression is a mechanism that might contribute to clonal expansion in chronic myeloid leukaemia (CML). Since cell death following exposure to ionizing radiation and many chemotherapeutic agents can occur by the apoptotic pathway, inhibition of apoptosis would be expected to confer a relative resistance to these treatments. Similarly, cells deprived of growth factors in vitro die by apoptosis, and inhibition of apoptosis would therefore be expected to allow cells to survive better in growth factor-deprived conditions. We found that the survival of normal and CML myeloid progenitors was the same after in vitro incubation in deprived conditions and after treatment with X-irradiation or glucocorticoids. We also found that mature cells in colonies produced by CML progenitors (CFU-GM) did not survive better than those produced by normal progenitor cells. Flow cytometric analysis of propidium iodide-stained cells provided a direct indication that the degree of apoptosis may correspond to the degree of deprivation. These results suggest that inhibition of apoptosis may not be the primary mechanism whereby BCR-ABL influences the expansion of the malignant clone in CML. (Author).

  9. Impact of Age and Insulin-Like Growth Factor-1 on DNA Damage Responses in UV-Irradiated Human Skin

    Directory of Open Access Journals (Sweden)

    Michael G. Kemp

    2017-02-01

    Full Text Available The growing incidence of non-melanoma skin cancer (NMSC necessitates a thorough understanding of its primary risk factors, which include exposure to ultraviolet (UV wavelengths of sunlight and age. Whereas UV radiation (UVR has long been known to generate photoproducts in genomic DNA that promote genetic mutations that drive skin carcinogenesis, the mechanism by which age contributes to disease pathogenesis is less understood and has not been sufficiently studied. In this review, we highlight studies that have considered age as a variable in examining DNA damage responses in UV-irradiated skin and then discuss emerging evidence that the reduced production of insulin-like growth factor-1 (IGF-1 by senescent fibroblasts in the dermis of geriatric skin creates an environment that negatively impacts how epidermal keratinocytes respond to UVR-induced DNA damage. In particular, recent data suggest that two principle components of the cellular response to DNA damage, including nucleotide excision repair and DNA damage checkpoint signaling, are both partially defective in keratinocytes with inactive IGF-1 receptors. Overcoming these tumor-promoting conditions in aged skin may therefore provide a way to lower aging-associated skin cancer risk, and thus we will consider how dermal wounding and related clinical interventions may work to rejuvenate the skin, re-activate IGF-1 signaling, and prevent the initiation of NMSC.

  10. Apoptosis in chronic myeloid leukaemia: normal responses by progenitor cells to growth factor deprivation, X-irradiation and glucocorticoids

    International Nuclear Information System (INIS)

    Amos, T.A.S.; Lewis, J.L.; Grand, F.H.; Gooding, R.P.; Goldman, J.M.; Gordon, M.Y.

    1995-01-01

    Inhibition of apoptosis (genetically programmed active cell death) by p210 BCR-ABL expression is a mechanism that might contribute to clonal expansion in chronic myeloid leukaemia (CML). Since cell death following exposure to ionizing radiation and many chemotherapeutic agents can occur by the apoptotic pathway, inhibition of apoptosis would be expected to confer a relative resistance to these treatments. Similarly, cells deprived of growth factors in vitro die by apoptosis, and inhibition of apoptosis would therefore be expected to allow cells to survive better in growth factor-deprived conditions. We found that the survival of normal and CML myeloid progenitors was the same after in vitro incubation in deprived conditions and after treatment with X-irradiation or glucocorticoids. We also found that mature cells in colonies produced by CML progenitors (CFU-GM) did not survive better than those produced by normal progenitor cells. Flow cytometric analysis of propidium iodide-stained cells provided a direct indication that the degree of apoptosis may correspond to the degree of deprivation. These results suggest that inhibition of apoptosis may not be the primary mechanism whereby BCR-ABL influences the expansion of the malignant clone in CML. (Author)

  11. Multifractal characterization of single wall carbon nanotube thin films surface upon exposure to optical parametric oscillator laser irradiation

    International Nuclear Information System (INIS)

    Ţălu, Ştefan; Marković, Zoran; Stach, Sebastian; Todorović Marković, B.; Ţălu, Mihai

    2014-01-01

    This study presents a multifractal approach, obtained with atomic force microscopy analysis, to characterize the structural evolution of single wall carbon nanotube thin films upon exposure to optical parametric oscillator laser irradiation at wavelength of 430 nm. Microstructure and morphological changes of carbon nanotube films deposited on different substrates (mica and TGX grating) were recorded by atomic force microscope. A detailed methodology for surface multifractal characterization, which may be applied for atomic force microscopy data, was presented. Multifractal analysis of surface roughness revealed that carbon nanotube films surface has a multifractal geometry at various magnifications. The generalized dimension D q and the singularity spectrum f(α) provided quantitative values that characterize the local scale properties of carbon nanotube films surface morphology at nanometer scale. Multifractal analysis provides different yet complementary information to that offered by traditional surface statistical parameters.

  12. Exposure to 56Fe irradiation accelerates normal brain aging and produces deficits in spatial learning and memory

    Science.gov (United States)

    Shukitt-Hale, Barbara; Casadesus, Gemma; Carey, Amanda N.; Rabin, Bernard M.; Joseph, James A.

    Previous studies have shown that radiation exposure, particularly to particles of high energy and charge (HZE particles) such as 56Fe, produces deficits in spatial learning and memory. These adverse behavioral effects are similar to those seen in aged animals. It is possible that these shared effects may be produced by the same mechanism. For example, an increased release of reactive oxygen species, and the subsequent oxidative stress and inflammatory damage caused to the central nervous system, is likely responsible for the deficits seen in aging and following irradiation. Therefore, dietary antioxidants, such as those found in fruits and vegetables, could be used as countermeasures to prevent the behavioral changes seen in these conditions. Both aged and irradiated rats display cognitive impairment in tests of spatial learning and memory such as the Morris water maze and the radial arm maze. These rats have decrements in the ability to build spatial representations of the environment, and they utilize non-spatial strategies to solve tasks. Furthermore, they show a lack of spatial preference, due to a decline in the ability to process or retain place (position of a goal with reference to a “map” provided by the configuration of numerous cues in the environment) information. These declines in spatial memory occur in measures dependent on both reference and working memory, and in the flexibility to reset mental images. These results show that irradiation with 56Fe high-energy particles produces age-like decrements in cognitive behavior that may impair the ability of astronauts, particularly middle-aged ones, to perform critical tasks during long-term space travel beyond the magnetosphere.

  13. Malignant transformation of guinea pig cells after exposure to ultraviolet-irradiated guinea pig cytomegalovirus

    International Nuclear Information System (INIS)

    Isom, H.C.; Mummaw, J.; Kreider, J.W.

    1983-01-01

    Guinea pig cells were malignantly transformed in vitro by ultraviolet (uv)-irradiated guinea pig cytomegalovirus (GPCMV). When guinea pig hepatocyte monolayers were infected with uv-irradiated GPCMV, three continuous epithelioid cell lines which grew in soft agarose were established. Two independently derived GPCMV-transformed liver cells and a cell line derived from a soft agarose clone of one of these lines induced invasive tumors when inoculated subcutaneously or intraperitoneally into nude mice. The tumors were sarcomas possibly derived from hepatic stroma or sinusoid. Transformed cell lines were also established after infection of guinea pig hepatocyte monolayers with human cytomegalovirus (HCMV) or simian virus 40 (SV40). These cell lines also formed colonies in soft agarose and induced sarcomas in nude mice. It is concluded that (i) GPCMV can malignantly transform guinea pig cells; (ii) cloning of GPCMV-transformed cells in soft agarose produced cells that induced tumors with a shorter latency period but with no alteration in growth rate or final tumor size; and (iii) the tumors produced by GPCMV-and HCMV-transformed guinea pig cells were more similar to each other in growth rate than to those induced by SV40-transformed guinea pig cells

  14. Simulated Irradiation of Samples in HFIR for use as Possible Test Materials in the MPEX (Material Plasma Exposure Experiment) Facility

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Ronald James [ORNL; Rapp, Juergen [ORNL

    2014-01-01

    The importance of Plasma Material Interaction (PMI) is a major concern in fusion reactor design and analysis. The Material-Plasma Exposure eXperiment (MPEX) facility will explore PMI under fusion reactor plasma conditions. Samples with accumulated displacements per atom (DPA) damage produced by irradiations in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) will be studied in the MPEX facility. The project presented in this paper involved performing assessments of the induced radioactivity and resulting radiation fields of a variety of potential fusion reactor materials. The scientific code packages MCNP and SCALE were used to simulate irradiation of the samples in HFIR; generation and depletion of nuclides in the material and the subsequent composition, activity levels, gamma radiation fields, and resultant dose rates as a function of cooling time. These state-of-the-art simulation methods were used in addressing the challenge of the MPEX project to minimize the radioactive inventory in the preparation of the samples for inclusion in the MPEX facility.

  15. Lymphoid irradiation in intractable rheumatoid arthritis: effects on the production of immunoglobulins and rheumatoid factors

    International Nuclear Information System (INIS)

    Hanly, J.G.; Bresnihan, B.; Hassan, J.; Whelan, A.; Feighery, C.; Moriarty, M.

    1985-01-01

    Changes in the production of immunoglobulins and rheumatoid factors (RF's) were studied in 20 patients with intractable rheumatoid arthritis (RA) following total doses of 750 rad or 2,000 rad lymphoid irradiation. Over a 12 month follow up period there was no consistent change in absolute serum or synovial fluid levels, or in synovial membrane production of either total IgG, IgA or IgM, or the corresponding RF fractions. The in-vitro production of immunoglobulins and IgM RF by peripheral blood mononuclear cells was also unaltered, except for one patient who had a dramatic rise in IgM RF production. Over the same period there was a significant overall reduction in disease activity following both doses of radiotherapy. It is concluded that the clinical response which occurs following lymphoid irradiation is not due to a reduction in RF production. Furthermore, the production of RF's appears to be unaffected by the changes in T cell immunity which occur following lymphoid irradiation. (author)

  16. Inactivation of RNA Viruses by Gamma Irradiation: A Study on Mitigating Factors

    Directory of Open Access Journals (Sweden)

    Adam J. Hume

    2016-07-01

    Full Text Available Effective inactivation of biosafety level 4 (BSL-4 pathogens is vital in order to study these agents safely. Gamma irradiation is a commonly used method for the inactivation of BSL-4 viruses, which among other advantages, facilitates the study of inactivated yet morphologically intact virions. The reported values for susceptibility of viruses to inactivation by gamma irradiation are sometimes inconsistent, likely due to differences in experimental protocols. We analyzed the effects of common sample attributes on the inactivation of a recombinant vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein and green fluorescent protein. Using this surrogate virus, we found that sample volume and protein content of the sample modulated viral inactivation by gamma irradiation but that air volume within the sample container and the addition of external disinfectant surrounding the sample did not. These data identify several factors which alter viral susceptibility to inactivation and highlight the usefulness of lower biosafety level surrogate viruses for such studies. Our results underscore the need to validate inactivation protocols of BSL-4 pathogens using “worst-case scenario” procedures to ensure complete sample inactivation.

  17. Environmental exposures as a risk factor for fibrolamellar carcinoma.

    Science.gov (United States)

    Graham, Rondell P; Craig, John R; Jin, Long; Oliveira, Andre M; Bergquist, John R; Truty, Mark J; Mounajjed, Taofic; Greipp, Patricia T; Torbenson, Michael S

    2017-06-01

    Fibrolamellar carcinoma was first described in 1956. Subsequent large studies failed to identify cases before 1939 (the start of the World War II). This finding, combined with the presence of aryl hydrocarbon receptors on the tumor cells, have suggested that fibrolamellar carcinomas may be caused by environmental exposures that are new since World War II. To investigate this possibility, the surgical pathology files before 1939 were reviewed for hepatocellular carcinomas resected in young individuals. Two cases of fibrolamellar carcinoma were identified, from 1915 to 1924. The diagnosis of fibrolamellar carcinoma was confirmed at the histologic, ultrastructural and proteomic levels. These two fibrolamellar carcinoma cases clarify a key aspect of fibrolamellar carcinoma biology, reducing the likelihood that these tumors result exclusively from post World War II environmental exposures.

  18. A Simple PV Inverter Power Factor Control Method Based on Solar Irradiance Variation

    DEFF Research Database (Denmark)

    Gökmen, Nuri; Hu, Weihao; Chen, Zhe

    2017-01-01

    There has been a significant rise in photovoltaic (PV) system installations throughout the last decade. This has posed some technical challenges to the distribution grid operators. Unfamiliar impacts of these relatively new energy sources now should be handled more comprehensively. The rigidity...... of these impacts mostly depends on PV penetration level, grid and weather characteristics as well as the interaction of load and generation. In this study, a reactive power control method is proposed benefitting from solar irradiance measurements in weather stations. Accordingly, power factors of PV inverters...

  19. The influence of chemical degradation during dietary exposures to fish on biomagnification factors and bioaccumulation factors.

    Science.gov (United States)

    Arnot, Jon A; Mackay, Donald

    2018-01-24

    The chemical dietary absorption efficiency (E D ) quantifies the amount of chemical absorbed by an organism relative to the amount of chemical an organism is exposed to following ingestion. In particular, E D can influence the extent of bioaccumulation and biomagnification for hydrophobic chemicals. A new E D model is developed to quantify chemical process rates in the gastrointestinal tract (GIT). The new model is calibrated with critically evaluated measured E D values (n = 250) for 80 hydrophobic persistent chemicals. The new E D model is subsequently used to estimate chemical reaction rate constants (k R ) assumed to occur in the lumen of the GIT from experimental dietary exposure tests (n = 255) for 165 chemicals. The new k R estimates are corroborated with k R estimates for the same chemicals from the same data derived previously by other methods. The roles of k R and the biotransformation rate constant (k B ) on biomagnification factors (BMFs) determined under laboratory test conditions and on BMFs and bioaccumulation factors (BAFs) in the environment are examined with the new model. In this regard, differences in lab and field BMFs are highlighted. Recommendations to address uncertainty in E D and k R data are provided.

  20. Study of effective factors in detection of irradiated food using thermoluminescence based on the models of reference minerals

    International Nuclear Information System (INIS)

    Miyahara, Makoto; Sugi, Eriko; Katoh, Takashi; Hironiwa, Takayuki; Sunaga, Hiromi; Luo, Ling Z.

    2012-01-01

    ). The peak positions are almost the same as those of original components and would not be affected by the mixing ratio. But TL ratio could not be used to determine irradiated food because mixing would reduce it remarkably. Some of the glow curves were simulated by a computer program. In conclusion, T1i/n is a key factor in an irradiated food determination practice for sample containing feldspar, rather than TL ratio. - Highlights: ► The TL method is standard for detection of irradiated food. ► It describes the peak temperature (T1) and TL ratio for non-heated or non-mixed sample. ► Effects of preheating or mixing processes based on the GSM samples on the T1 and TL ratio were examined. ► The peak temperature T1, rather than TL ratio, is a key factor.

  1. The rate of DNA synthesis in normal human and ataxia telangiectasia cells after exposure to X-irradiation

    International Nuclear Information System (INIS)

    Wit, J. de; Bootsma, D.; Jaspers, N.G.J.; Rijksverdedigingsorganisatie TNO, Rijswijk

    1981-01-01

    The rate of DNA synthesis was studied in normal cell strains and in strains from patients suffering from the inherited disorder ataxia telangiectasia (AT). After exposure to relatively low doses of oxic X-rays (0- 4 krad) DNA synthesis was depressed in AT cell strains to a significantly lesser extent than in normal cells. This response was observed in both an excision-deficient and an excision-proficient strain. In contrast, there was no difference in DNA-synthesis inhibition between AT and normal cells after UV exposure. After X-irradiation of cells from patients with xeroderma pigmentosum, both complementation group A and XP variants, the observed rate of DNA synthesis was equal to that in normal cells. An exception was the strain XP3BR which has been shown to be X-ray-sensitive. This strain exhibited diminished DNA synthesis inhibition after X-ray doses below 1 krad. These data suggest a relationship between hypersensitivity to X-rays and diminished depression of DNA synthesis. (orig.)

  2. Psychosocial Factors at Work and Blood-Borne Exposure among Nurses

    Directory of Open Access Journals (Sweden)

    R Mehrdad

    2014-01-01

    Full Text Available Background: Exposure to human blood and body fluids is a common risk for nurses. Many factors can affect the prevalence and incidence of this occupational hazard. Psychosocial factors at work may be a risk factor for the exposure. Objective: To assess needle stick, sharp injury and mucus exposure to blood-borne pathogens among nurses in Iran and to determine the association between these exposures and psychosocial factors at work. Methods: A cross-sectional study was conducted on nurses in a public hospital, Tehran, Iran. 364 nurses received and 339 completed and returned a self-reported questionnaire containing demographic data, history of exposure to blood-borne pathogens at work during previous year and the General Nordic questionnaire for psychological and social factors at work (QPS Nordic 34+ Questionnaire. Results: Of 339 participants, 197 (58.1% reported needle-stick injury, 186 (54.6% reported another type of sharp injury, and 112 (33% reported a mucous membrane exposure during the previous year. More than half of the participants who had history of exposure, had not reported it. Those with middle or high level of stress had higher crude and adjusted odds than those with lower stress for all kinds of exposure. Adjusted odds ratios for high stress group (ranging from 2.8 to 4.4 were statistically different from 1. Conclusion: There is a high prevalence of needle-stick and sharp injury and mucous membrane exposure to patients' blood or body fluids among studied nurses. There is a significant association between increasing psychosocial factors at work and exposure to blood-borne pathogens among this group of nurses.

  3. Health condition of children irradiated in utero

    Energy Technology Data Exchange (ETDEWEB)

    Stepanova, E [Research Center for Radiation Medicine, Kiev (Ukraine)

    1997-09-01

    Among the children exposed to ionizing radiation, the ones irradiated in utero constitute a group under special surveillance. The greatest sensitivity of the organism to the effects of radiative factors occurs in the neonatal period of development and the forthcoming life span with irradiation effects is the longest for these children. Children with acute exposure, with chronic exposure and control group were encompassed by this study - 1144 children altogether. 9 figs, 2 tabs.

  4. Health condition of children irradiated in utero

    International Nuclear Information System (INIS)

    Stepanova, E.

    1997-01-01

    Among the children exposed to ionizing radiation, the ones irradiated in utero constitute a group under special surveillance. The greatest sensitivity of the organism to the effects of radiative factors occurs in the neonatal period of development and the forthcoming life span with irradiation effects is the longest for these children. Children with acute exposure, with chronic exposure and control group were encompassed by this study - 1144 children altogether. 9 figs, 2 tabs

  5. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    International Nuclear Information System (INIS)

    Taghinejad-Roudbaneh, M.; Ebrahimi, S.R.; Azizi, S.; Shawrang, P.

    2010-01-01

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased (P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased (P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved (P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  6. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Energy Technology Data Exchange (ETDEWEB)

    Taghinejad-Roudbaneh, M., E-mail: mtaghinejad@iaut.ac.i [Department of Animal Science, Faculty of Agriculture, Islamic Azad University, Tabriz Branch, P.O. Box 51589, Tabriz (Iran, Islamic Republic of); Ebrahimi, S.R. [Department of Animal Science, Faculty of Agriculture, Shahr-e-Qods Branch, Islamic Azad University, P.O. Box 37515-374, Shahr-e-Qods (Iran, Islamic Republic of); Azizi, S. [Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, P.O. Box 57155-1177, Urmia (Iran, Islamic Republic of); Shawrang, P. [Nuclear Science and Technology Research Institute, Agricultural, Medical and Industrial Research School, Atomic Energy Organization of Iran, P.O. Box 31485-498, Karaj (Iran, Islamic Republic of)

    2010-12-15

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased (P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased (P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved (P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  7. Clinical and pathologic factors predictive of biochemical control following post-prostatectomy irradiation

    International Nuclear Information System (INIS)

    Stromberg, Jannifer S.; Ziaja, Ellen L.; Horwitz, Eric M.; Vicini, Frank A.; Brabbins, Donald S.; Dmuchowski, Carl F.; Gonzalez, Jose; Martinez, Alvaro A.

    1996-01-01

    Purpose/Objective: Indications for post-prostatectomy radiation therapy are not well defined. We reviewed our experience treating post-prostatectomy patients with external beam irradiation to assess clinical and pathologic factors predictive of biochemical control. Materials and Methods: Between 1/87 and 3/93, 61 patients received post-operative tumor bed irradiation with a median dose of 59.4 Gy (50.4 - 68 Gy). Median follow-up was 4.1 years (7.6 months - 8.3 years) from irradiation. Patients were treated for the following reasons: 1) adjuvantly, within 6 months of surgery for extracapsular extension, seminal vesicle involvement, or positive surgical margins (n=38); 2) persistently elevated PSA post-operatively (n=2); 3) rising PSA >6 months after surgery (n=9); and 4) biopsy proven local recurrence (n=12). No patients had known nodal or metastatic disease. All patients had post-radiation PSA data available. Biochemical control was the endpoint studied using Kaplan-Meier life table analysis. Biochemical control was defined as the ability to maintain an undetectable PSA ( 4 and ≤1 0, >10 and ≤20, and > 20 ng/ml. The 3 year actuarial rates of biochemical control were 100% for group 1, 66.7% for group 2, 61.5% for group 3, and 28.6% for group 4. Pre-RT PSA values were also evaluated. Univariate Cox models indicated lower presurgical and pre-RT PSA values were predictive of biochemical control (p=0.017, p 6 months after surgery (group 3), the 3 year actuarial rate of biochemical control was 55.6%. The 3 year actuarial rate of biochemical control for patients treated for a biopsy proven recurrence (group 4) was 8.3%. By pair-wise log rank test, the rates of biochemical control were significantly different between groups 1 and 3 (p=0.036), groups 1 and 4 (p<0.001), and groups 3 and 4 (p=0.009). Conclusion: Biochemical control was achieved in approximately half of the patients treated with post-operative prostatic fossa irradiation. Elevated presurgical and pre

  8. Extracellular hydrogen peroxide produced under irradiation as the most important factor in the lethality of gamma-irradiated Paramecium tetraurelia

    International Nuclear Information System (INIS)

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

    1982-01-01

    It has been shown that the surviving fraction of γ-irradiated paramecia is correlated with the residual H 2 O 2 concentration in the extracellular medium which is strongly dependent on the bacterial concentration, that is, on the enzyme content in the culture medium. (author)

  9. Extracellular hydrogen peroxide produced under irradiation as the most important factor in the lethality of gamma-irradiated Paramecium tetraurelia

    Energy Technology Data Exchange (ETDEWEB)

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H. (Laboratoire de Biologie Medicale, 31 - Toulouse (France))

    1982-02-01

    It has been shown that the surviving fraction of ..gamma..-irradiated paramecia is correlated with the residual H/sub 2/O/sub 2/ concentration in the extracellular medium which is strongly dependent on the bacterial concentration, that is, on the enzyme content in the culture medium.

  10. Upregulated epidermal growth factor receptor expression following near-infrared irradiation simulating solar radiation in a three-dimensional reconstructed human corneal epithelial tissue culture model.

    Science.gov (United States)

    Tanaka, Yohei; Nakayama, Jun

    2016-01-01

    Humans are increasingly exposed to near-infrared (NIR) radiation from both natural (eg, solar) and artificial (eg, electrical appliances) sources. Although the biological effects of sun and ultraviolet (UV) exposure have been extensively investigated, the biological effect of NIR radiation is still unclear. We previously reported that NIR as well as UV induces photoaging and standard UV-blocking materials, such as sunglasses, do not sufficiently block NIR. The objective of this study was to investigate changes in gene expression in three-dimensional reconstructed corneal epithelial tissue culture exposed to broad-spectrum NIR irradiation to simulate solar NIR radiation that reaches human tissues. DNA microarray and quantitative real-time polymerase chain reaction analysis were used to assess gene expression levels in a three-dimensional reconstructed corneal epithelial model composed of normal human corneal epithelial cells exposed to water-filtered broad-spectrum NIR irradiation with a contact cooling (20°C). The water-filter allowed 1,000-1,800 nm wavelengths and excluded 1,400-1,500 nm wavelengths. A DNA microarray with >62,000 different probes showed 25 and 150 genes that were up- or downregulated by at least fourfold and twofold, respectively, after NIR irradiation. In particular, epidermal growth factor receptor (EGFR) was upregulated by 19.4-fold relative to control cells. Quantitative real-time polymerase chain reaction analysis revealed that two variants of EGFR in human corneal epithelial tissue were also significantly upregulated after five rounds of 10 J/cm(2) irradiation (Psolar energy reaching the Earth is in the NIR region, which cannot be adequately blocked by eyewear and thus can induce eye damage with intensive or long-term exposure, protection from both UV and NIR radiation may prevent changes in gene expression and in turn eye damage.

  11. Postoperative irradiation of incompletely excised gemistocytic astrocytomas. Clinical outcome and prognostic factors

    International Nuclear Information System (INIS)

    Nowak-Sadzikowska, J.; Glinski, B.; Szpytma, T.; Pluta, E.

    2005-01-01

    Background and purpose: although gemistocytic astrocytomas are considered slow-growing tumors, they often behave aggressively and carry the least favorable prognosis among low-grade astrocytomas. The aim of this study is to evaluate the outcomes and prognostic factors of patients with incompletely excised gemistocytic astrocytomas irradiated postoperatively. Patients and methods: records of 48 patients with incompletely excised gemistocytic astrocytoma, irradiated between 1976 and 1998 at the department of radiation oncology, Maria Sklodowska-curie Memorial Cancer Center, Cracow, Poland, were reviewed. The total dose ranged from 50 to 60 Gy (mean: 59.35, median: 60 Gy) delivered in daily fractions of 2 Gy, 5 days a week. The treatment volume covered the residual tumor with a margin of 1-2 cm. Results: toxicity was acceptable. The overall actuarial survival rates at 5 and 10 years were 30% and 17%, respectively. Age and gender had an influence on overall survival by univariate and multivariate analysis (p < 0.05). Patients ≤ 35 years of age and female patients carried the best prognosis. Conclusion: in most patients with gemistocytic astrocytoma, combined surgery and postoperative radiotherapy result in only short-term survival. Older age is the most important unfavorable prognostic factor in patients with gemistocytic astrocytoma. (orig.)

  12. Gas-phase organics in environmental tobacco smoke: 2. Exposure-relevant emission factors and indirect exposures from habitual smoking

    Science.gov (United States)

    Singer, Brett C.; Hodgson, Alfred T.; Nazaroff, William W.

    Sorption of emitted gas-phase organic compounds onto material surfaces affects environmental tobacco smoke (ETS) composition and exposures indoors. We have introduced a new metric, the exposure relevant emission factor (EREF) that accounts for sorptive uptake and reemission to give the mass of individual ETS constituents available for exposure over a day in which smoking occurs. This paper describes month-long experiments to investigate sorption effects on EREFs and potential ETS exposures under habitual smoking conditions. Cigarettes were smoked in a 50-m 3 furnished room over a 3-h period 6-7 days per week, with continuous ventilation at 0.3, 0.6, or 2.1 h -1. Organic gas concentrations were measured every few days over 4-h "smoking", 10-h "post-smoking" and 10-h "background" periods. Concentration patterns of volatile ETS components including 1,3-butadiene, benzene and acrolein were similar to those calculated for a theoretical non-sorbing tracer, indicating limited sorption. Concentrations of ETS tracers, e.g. 3-ethenylpyridine (3-EP) and nicotine, and lower volatility toxic air contaminants including phenol, cresols, and naphthalene increased as experiments progressed, indicating mass accumulation on surfaces and higher desorption rates. Daily patterns stabilized after week 2, yielding a steady daily cycle of ETS concentrations associated with habitual smoking. EREFs for sorbing compounds were higher under steady cycle versus single-day smoking conditions by ˜50% for 3-EP, and by 2-3 times for nicotine, phenol, cresols, naphthalene, and methylnaphthalenes. Our results provide relevant information about potential indirect exposures from residual ETS (non-smoker enters room shortly after smoker finishes) and from reemission, and their importance relative to direct exposures (non-smoker present during smoking). Under the conditions examined, indirect exposures accounted for a larger fraction of total potential exposures for sorbing versus non-sorbing compounds

  13. Exposure to biomass smoke as a risk factor for oesophageal and ...

    African Journals Online (AJOL)

    Exposure to biomass smoke as a risk factor for oesophageal and gastric cancer in low-income populations: A systematic review. Violet Kayamba, Douglas C. Heimburger, Douglas R. Morgan, Masharip Atadzhanov, Paul Kelly ...

  14. Latent transforming growth factor beta1 activation in situ: quantitative and functional evidence after low-dose gamma-irradiation

    Science.gov (United States)

    Ehrhart, E. J.; Segarini, P.; Tsang, M. L.; Carroll, A. G.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1997-01-01

    The biological activity of transforming growth factor beta1 (TGF-beta) is controlled by its secretion as a latent complex in which it is noncovalently associated with latency-associated peptide (LAP). Activation is the extracellular process in which TGF-beta is released from LAP, and is considered to be a primary regulatory control. We recently reported rapid and persistent changes in TGF-beta immunoreactivity in conjunction with extracellular matrix remodeling in gamma-irradiated mouse mammary gland. Our hypothesis is that these specific changes in immunoreactivity are indicative of latent TGF-beta activation. In the present study, we determined the radiation dose response and tested whether a functional relationship exists between radiation-induced TGF-beta and collagen type III remodeling. After radiation exposures as low as 0.1 Gy, we detected increased TGF-beta immunoreactivity in the mammary epithelium concomitant with decreased LAP immunostaining, which are events consistent with activation. Quantitative image analysis demonstrated a significant (P=0.0005) response at 0.1 Gy without an apparent threshold and a linear dose response to 5 Gy. However, in the adipose stroma, loss of LAP demonstrated a qualitative threshold at 0.5 Gy. Loss of LAP paralleled induction of collagen III immunoreactivity in this tissue compartment. We tested whether TGF-beta mediates collagen III expression by treating animals with TGF-beta panspecific monoclonal antibody, 1D11.16, administered i.p. shortly before irradiation. Radiation-induced collagen III staining in the adipose stroma was blocked in an antibody dose-dependent manner, which persisted through 7 days postirradiation. RNase protection assay revealed that radiation-induced elevation of total gland collagen III mRNA was also blocked by neutralizing antibody treatment. These data provide functional confirmation of the hypothesis that radiation exposure leads to latent TGF-beta activation, support our interpretation of the

  15. Expression of transforming growth factor beta 1-related signaling proteins in irradiated vessels

    Energy Technology Data Exchange (ETDEWEB)

    Preidl, Raimund H.M.; Moebius, Patrick; Weber, Manuel; Neukam, Friedrich W.; Schlegel, Andreas; Wehrhan, Falk [University of Erlangen- Nuernberg, Department of Oral and Maxillofacial Surgery, Erlangen (Germany); University of Erlangen- Nuernberg, Erlangen (Germany); Amann, Kerstin [University of Erlangen- Nuernberg, Erlangen (Germany)

    2014-12-09

    Microvascular free tissue transfer is a standard method in head and neck reconstructive surgery. However, previous radiotherapy of the operative region is associated with an increased incidence in postoperative flap-related complications and complete flap loss. As transforming growth factor beta (TGF-β) 1 and galectin-3 are well known markers in the context of fibrosis and lectin-like oxidized low-density lipoprotein 1 (LOX-1) supports vascular atherosclerosis, the aim of this study was to evaluate the expression of TGF-β1 and related markers as well as LOX-1 in irradiated vessels. To evaluate the expression of galectin-3, Smad 2/3, TGF-β1, and LOX-1, 20 irradiated and 20 nonirradiated arterial vessels were used for immunohistochemical staining. We semiquantitatively assessed the ratio of stained cells/total number of cells (labeling index). Expression of galectin-3, Smad 2/3, and TGF-β1 was significantly increased in previously irradiated vessels compared with nonirradiated controls. Furthermore, LOX-1 was expressed significantly higher in irradiated compared with nonirradiated vessels. Fibrosis-related proteins like galectin-3, Smad 2/3, and TGF-β1 are upregulated after radiotherapy and support histopathological changes leading to vasculopathy of the irradiated vessels. Furthermore, postoperative complications in irradiated patients can be explained by increased endothelial dysfunction caused by LOX-1 in previously irradiated patients. Consequently, not only TGF-β1 but also galectin-3inhibitors may decrease complications after microsurgical tissue transfer. (orig.) [German] Der freie mikrovaskulaere Gewebetransfer gilt heute als fester Standard in der rekonstruktiven Kopf-Hals-Chirurgie. Es zeigte sich jedoch, dass im Falle einer stattgehabten Bestrahlung im Operationsgebiet mit einer erhoehten Rate an transplantatbezogenen Komplikationen gerechnet werden muss. Sowohl TGF-β1 als auch Galektin-3 sind bekannte Mediatoren in Bezug auf die Fibroseentstehung

  16. Effects of recombinant human granulocyte colony-stimulating factor on central and peripheral T lymphocyte reconstitution after sublethal irradiation in mice

    International Nuclear Information System (INIS)

    Zhao Hongxia; Guo Mei; Sun Xuedong; Ai Huisheng; Sun Wanjun; Hu Hailan; Wei Li

    2013-01-01

    Granulocyte colony-stimulating factor (G-CSF) is one of the most critical cytokines used for the treatment of acute radiation syndrome (ARS). In addition to the hematopoietic effects of G-CSF on the differentiation and proliferation of myeloid progenitor cells, G-CSF is also known to have immunomodulatory effects. The aim of the present study was to investigate whether G-CSF could accelerate central and peripheral T lymphocyte recovery after a sublethal dose of irradiation. Female BALB/c mice were subjected to 6 Gy of total body irradiation and then were treated with either 100 μg/kg G-CSF or an equal volume of PBS once daily for 14 days. Percentages of thymocyte subpopulations including CD4- CD8-, CD4+ CD8+, CD4+ CD8- and CD4- CD8+ T cells, peripheral CD3+, CD4+ and CD8+ cells were analyzed by flow cytometry. Recent thymic emigrants (RTEs) were assessed by real-time polymerase chain reaction (PCR) using primers specific to the 257-bp T cell receptor rearrangement excision circles (sjTRECs). The proliferative capacity of splenic mononuclear cells upon exposure to ConA was measured by using the Cell Count Kit-8 (CCK-8). G-CSF treatment promoted thymocyte regeneration, accelerated the recovery of CD4+ CD8+ cells and increased the frequency of thymocyte sjTRECs. These effects were more prominent at early time points (Day 28) after irradiation. G-CSF also increased the rate of recovery of peripheral CD3+, CD4+ and CD8+ cells and shortened the period of severe lymphopenia following irradiation. G-CSF also increased the splenic mononuclear cell mitotic responsiveness to ConA more than control-treated cells. Our results show that G-CSF accelerates T cell recovery through both thymic-dependent and thymic-independent pathways, which could be used to increase the rate of immune reconstitution after sublethal irradiation. (author)

  17. Radiation and host factors in human thyroid tumors following thymus irradiation

    International Nuclear Information System (INIS)

    Shore, R.E.; Pasternack, B.S.; Woodard, E.D.; Hempelmann, L.H.

    1980-01-01

    Thyroid tumor data from the 1971 survey of the Rochester, New York thymus irradiated population are further analyzed to study radiobiological and host factors. The analyses were based on the approx. 2650 irradiated subjects and 4800 sibling controls who had 5 or more years of follow-up. Twenty-four thyroid cancers and 52 thyroid adenomas were found in the irradiated group, and O thyroid cancers and 6 adenomas among the controls. The overall risk estimates were 3.8 thyroid cancers/10 6 persons/yr/rad and 4.5 thyroid adenomas/10 6 persons/yr/rad. The dose-response data (thyroid dose range of 5 to > 1000 rad) for thyroid cancer indicate both a linear and a dose-squared component, but no dose-squared component is evident for thyroid adenomas. At lower total doses (< 400 rad) there was a suggestion that dose fractionation diminished the thyroid cancer response, but a similar fractionation effect was not found for thyroid adenomas. The temporal pattern of tumors suggested an extended plateau of excess tumor production, rather than a wavelike temporal pattern. There was no evidence for an inverse relationship between thyroid radiation dose and thyroid cancer latency. Female and Jewish subjects had a higher risk of radiation-induced thyroid cancer than did their respective counterparts. The additive and multiplicative models of radiation effects were compared with respect to sex differences; neither model provided a superior fit to the data. The tentative nature of the conclusions is stressed because of the relatively small number of thyroid cancers. (author)

  18. Development and validation of a job exposure matrix for physical risk factors in low back pain.

    Directory of Open Access Journals (Sweden)

    Svetlana Solovieva

    Full Text Available OBJECTIVES: The aim was to construct and validate a gender-specific job exposure matrix (JEM for physical exposures to be used in epidemiological studies of low back pain (LBP. MATERIALS AND METHODS: We utilized two large Finnish population surveys, one to construct the JEM and another to test matrix validity. The exposure axis of the matrix included exposures relevant to LBP (heavy physical work, heavy lifting, awkward trunk posture and whole body vibration and exposures that increase the biomechanical load on the low back (arm elevation or those that in combination with other known risk factors could be related to LBP (kneeling or squatting. Job titles with similar work tasks and exposures were grouped. Exposure information was based on face-to-face interviews. Validity of the matrix was explored by comparing the JEM (group-based binary measures with individual-based measures. The predictive validity of the matrix against LBP was evaluated by comparing the associations of the group-based (JEM exposures with those of individual-based exposures. RESULTS: The matrix includes 348 job titles, representing 81% of all Finnish job titles in the early 2000s. The specificity of the constructed matrix was good, especially in women. The validity measured with kappa-statistic ranged from good to poor, being fair for most exposures. In men, all group-based (JEM exposures were statistically significantly associated with one-month prevalence of LBP. In women, four out of six group-based exposures showed an association with LBP. CONCLUSIONS: The gender-specific JEM for physical exposures showed relatively high specificity without compromising sensitivity. The matrix can therefore be considered as a valid instrument for exposure assessment in large-scale epidemiological studies, when more precise but more labour-intensive methods are not feasible. Although the matrix was based on Finnish data we foresee that it could be applicable, with some modifications, in

  19. Development and validation of a job exposure matrix for physical risk factors in low back pain.

    Science.gov (United States)

    Solovieva, Svetlana; Pehkonen, Irmeli; Kausto, Johanna; Miranda, Helena; Shiri, Rahman; Kauppinen, Timo; Heliövaara, Markku; Burdorf, Alex; Husgafvel-Pursiainen, Kirsti; Viikari-Juntura, Eira

    2012-01-01

    The aim was to construct and validate a gender-specific job exposure matrix (JEM) for physical exposures to be used in epidemiological studies of low back pain (LBP). We utilized two large Finnish population surveys, one to construct the JEM and another to test matrix validity. The exposure axis of the matrix included exposures relevant to LBP (heavy physical work, heavy lifting, awkward trunk posture and whole body vibration) and exposures that increase the biomechanical load on the low back (arm elevation) or those that in combination with other known risk factors could be related to LBP (kneeling or squatting). Job titles with similar work tasks and exposures were grouped. Exposure information was based on face-to-face interviews. Validity of the matrix was explored by comparing the JEM (group-based) binary measures with individual-based measures. The predictive validity of the matrix against LBP was evaluated by comparing the associations of the group-based (JEM) exposures with those of individual-based exposures. The matrix includes 348 job titles, representing 81% of all Finnish job titles in the early 2000s. The specificity of the constructed matrix was good, especially in women. The validity measured with kappa-statistic ranged from good to poor, being fair for most exposures. In men, all group-based (JEM) exposures were statistically significantly associated with one-month prevalence of LBP. In women, four out of six group-based exposures showed an association with LBP. The gender-specific JEM for physical exposures showed relatively high specificity without compromising sensitivity. The matrix can therefore be considered as a valid instrument for exposure assessment in large-scale epidemiological studies, when more precise but more labour-intensive methods are not feasible. Although the matrix was based on Finnish data we foresee that it could be applicable, with some modifications, in other countries with a similar level of technology.

  20. Elimination of Salmonella in froglegs by irradiation. Coordinated programme on factors influencing the utilization of food irradiation processes

    International Nuclear Information System (INIS)

    Tambunan, P.R.

    1984-11-01

    Living frogs and their internal organs are highly contaminated with several serotypes of Salmonella. The high level of contamination was carried along with frog legs upon arrival at processing plants. Washing in chlorinated water and freezing reduced but did not eliminate Salmonella from the product. Irradiating frog legs artificially contaminated with Salmonella up to 10 6 /g before freezing showed that a dose of 3 kGy and above resulted in no detection of the bacteria. If irradiation was carried out after freezing, a dose of 4 kGy and above has to be used. The latter procedure appears to be more feasible commercially than the former one. It was concluded that a combination of chlorination, freezing and irradiation with a dose ranging from 3 to 6 kGy should provide sufficient conditions for elimination of Salmonella in the product. The treatment also results in lowering the total viable count to less than 500,000 cells/g to conform with the standard requirements for export

  1. Stem cell factor enhances the survival of murine intestinal stem cells after photon irradiation

    International Nuclear Information System (INIS)

    Leigh, B.R.; Khan, W.; Hancock, S.L.

    1995-01-01

    Recombinant rat stem cell factor (SCF) has been shown to decrease lethality in mice exposed to total-body irradiation (TBI) in the lower range of lethality through radioprotection of hematopoietic stem cells and acceleration of bone marrow repopulation. This study evaluates the effect of SCF on the survival of the intestinal mucosal stem cell after TBI. This non-hematopoietic cell is clinically relevant. Gastrointestinal toxicity is common during and after abdominal and pelvic radiation therapy and limits the radiation dose in these regions. As observed with bone marrow, the administration of SCF to mice prior to TBI enhanced the survival of mouse duodenal crypt stem cells. The maximum enhancement of survival was seen when 100 μ/kg of SCF was given intraperitoneally 8 h before irradiation. This regimen increased the survival of duodenal crypt stem cells after 12.0 Gy TBI from 22.5 ± 0.7 per duodenal cross section for controls to 30.0 ± 1.7 after treatment with SCF (P=0.03). The TBI dose producing 50% mortality of 6 days (LD 50/6 ) was increased from 14.9 Gy for control mice to 19.0 Gy for mice treated with SCF (dose modification factor = 1.28). These findings demonstrate that SCF (dose modification factor = 1.28). These findings demonstrate that SCF has radioprotective effects on a non-hematopoietic stem cell population and suggest that SCF may be of clinical value in preventing radiation injury to the intestine. 29 refs., 4 figs

  2. Prevalence of sun exposure and its associated factors in southern Brazil: a population-based study.

    Science.gov (United States)

    Duquia, Rodrigo Pereira; Menezes, Ana Maria Baptista; Almeida, Hiram Larangeira de; Reichert, Felipe Fossati; Santos, Iná da Silva dos; Haack, Ricardo Lanzetta; Horta, Bernardo Lessa

    2013-01-01

    Sunlight exposure is responsible for a large number of dermatological diseases. We estimated the prevalence of sunlight exposure and its associated factors in adults from southern Brazil in a cross-sectional, population-based study. We investigated a representative sample of individuals aged ≥ 20 years (n=3,136). Sunlight exposure and its associated factors were evaluated in two distinct situations: at leisure time and at work. The time period investigated ranged from December 2004 to March 2005, comprising 120 days of the highest ultraviolet index in the urban area of the city of Pelotas, in southern Brazil. The participants were asked about sunlight exposure for at least 20 minutes between 10 A.M. and 4 P.M. The analysis was stratified by sex, and sunlight exposure was grouped into five categories. Among the 3,136 participants, prevalence of sunlight exposure at the beach was 32.8% (95% CI, 30.3 - 35.2) and 26.3% (95% CI, 24.2 28.3) among men and women, respectively. The prevalence at work was 39.8% (95% CI, 37.2 - 42.4) among men and 10.5% (95% CI, 9.1 - 12.0) among women. Age was inversely associated with sunlight exposure. Family income and achieved schooling were positively associated with sunlight exposure at leisure time and inversely associated with sunglight exposure at work. Self-reported skin color was not associated. Knowledge of any friend or relative who has been affected by skin cancer was positively associated with sunlight exposure among men at work. Despite the media campaigns on the harmful effects of excessive sunlight exposure, we found a high prevalence of sunlight exposure during a period of high ultraviolet index.

  3. Prevalence of sun exposure and its associated factors in southern Brazil: a population-based study*

    Science.gov (United States)

    Duquia, Rodrigo Pereira; Menezes, Ana Maria Baptista; de Almeida, Hiram Larangeira; Reichert, Felipe Fossati; dos Santos, Iná da Silva; Haack, Ricardo Lanzetta; Horta, Bernardo Lessa

    2013-01-01

    BACKGROUND Sunlight exposure is responsible for a large number of dermatological diseases. OBJECTIVE We estimated the prevalence of sunlight exposure and its associated factors in adults from southern Brazil in a cross-sectional, population-based study. METHODS We investigated a representative sample of individuals aged ≥ 20 years (n=3,136). Sunlight exposure and its associated factors were evaluated in two distinct situations: at leisure time and at work. The time period investigated ranged from December 2004 to March 2005, comprising 120 days of the highest ultraviolet index in the urban area of the city of Pelotas, in southern Brazil. The participants were asked about sunlight exposure for at least 20 minutes between 10 A.M. and 4 P.M. The analysis was stratified by sex, and sunlight exposure was grouped into five categories. RESULTS Among the 3,136 participants, prevalence of sunlight exposure at the beach was 32.8% (95% CI, 30.3 - 35.2) and 26.3% (95% CI, 24.2 28.3) among men and women, respectively. The prevalence at work was 39.8% (95% CI, 37.2 - 42.4) among men and 10.5% (95% CI, 9.1 - 12.0) among women. Age was inversely associated with sunlight exposure. Family income and achieved schooling were positively associated with sunlight exposure at leisure time and inversely associated with sunglight exposure at work. Self-reported skin color was not associated. Knowledge of any friend or relative who has been affected by skin cancer was positively associated with sunlight exposure among men at work. CONCLUSION Despite the media campaigns on the harmful effects of excessive sunlight exposure, we found a high prevalence of sunlight exposure during a period of high ultraviolet index. PMID:24068126

  4. Radiation-induced transformation of SV40-immortalized human thyroid epithelial cells by single and fractionated exposure to γ-irradiation in vitro

    International Nuclear Information System (INIS)

    Riches, A.C.; Herceg, Z.; Bryant, P.E.; Wynford-Thomas, D.

    1994-01-01

    Radiation-induced transformation of a human thyroid epithelial cell line (HTori-3) has been investigated following exposure to single and fractionated doses of γ-irradiation. The human epithelial cells were irradiated in vitro and following passaging, transplanted to the athymic nude mouse. Following a single exposure to γ-irradiation in the range 0.5-4Gy, 22 tumours were observed in 45 recipients and following three equal fractions in the range 0.5-4Gy per fraction, 18 tumours were observed in 31 recipients. Tumours were undifferentiated carcinomas and were observed from 7 to 20 weeks after transplantation. They occurred after similar radiation doses to those received by the children in the Belarus region of Ukraine, who developed thyroid tumours. The number of tumours observed, in each group receiving cells irradiated with a single dose of γ-irradiation in the range 0.5-4 Gy, was similar. Cell lines were established from some tumours and the tumorigenicity confirmed by retransplantation. These tumour cell lines were more radiosensitive than the human thyroid epithelial cell line they were derived from. This indicates that transformed cells were not being selected from a subpopulation within the parent cell line but that radiation-induced transformants were being induced de novo. The human origin of the tumours was established by karyotyping, immunocytochemical demonstration of human epithelial cytokeratins and p53 analysis. DNA fingerprinting confirmed that the tumours were derived from the original cell line. (author)

  5. Indoor Residential Chemical Exposures as Risk Factors for Asthmaand Allergy in Infants and Children: a Review

    Energy Technology Data Exchange (ETDEWEB)

    Mendell, M.J.

    2006-03-01

    Most research into effects of residential indoor air exposures on asthma and allergies has focused on exposures to biologic allergens, moisture and mold, endotoxin, or combustion byproducts. This paper briefly reviews reported findings on associations of asthma or allergy in infants or children with risk factors related to indoor chemical emissions from residential materials or surface coatings. Associations, some strong (e.g., odds ratios up to 13), were reported. The most frequently identified risk factors were formaldehyde, aromatic organic compounds such as toluene and benzene, plastic materials and plasticizers, and recent painting. Exposures and consequent effects from indoor sources may be exacerbated by decreased ventilation. Identified risk factors may be proxies for correlated exposures. Findings suggest the frequent occurrence of important but preventable effects on asthma and allergy in infants and children worldwide from modern residential building materials and coatings.

  6. Lithium-stimulated recovery of granulopoiesis after sublethal irradiation is not mediated via increased levels of colony stimulating factor (CSF)

    International Nuclear Information System (INIS)

    Gallicchio, V.S.; Chen, M.G.; Watts, T.D.

    1985-01-01

    Lithium accelerates the recovery of granulopoiesis following sublethal (2 Gy) whole body x-irradiation. Studies are described that further define this Li-mediated recovery by measuring the levels of colony-stimulating factor (CSF) present in serum from mice administered 105 μg/mouse (total dose) of ultra-pure Li 2 CO 3 for 3 days following irradiation. On days 1-28 following the last lithium dose, the serum was tested for its CSF activity against both normal non-adherent derived bone marrow target cells and non-adherent marrow cells from mice administered cyclophosphamide (200 mg/kg body weight). Serum was assayed at 0.01, 0.1, 1 and 10% final concentration. No significant difference in the total number of CFU-GM was observed from normal marrow using either serum from irradiated mice or lithium-treated and irradiated mice, although the irradiation did produce a 300% rise in CFU-GM colonies compared to normal serum (days 4 and 10-15). From regenerating marrow, a significant difference (P <= 0.01) was observed in CFU-GM cultured with serum at 0.1% concentration from irradiated and lithium-treated mice compared to irradiated mice without lithium. The presence of CSF was confirmed by its reduced activity in the presence of anti-(CSF). (U.K.)

  7. Severe Pulmonary Toxicity After Myeloablative Conditioning Using Total Body Irradiation: An Assessment of Risk Factors

    International Nuclear Information System (INIS)

    Kelsey, Chris R.; Horwitz, Mitchell E.; Chino, Junzo P.; Craciunescu, Oana; Steffey, Beverly; Folz, Rodney J.; Chao, Nelson J.; Rizzieri, David A.; Marks, Lawrence B.

    2011-01-01

    Purpose: To assess factors associated with severe pulmonary toxicity after myeloablative conditioning using total body irradiation (TBI) followed by allogeneic stem cell transplantation. Methods and Materials: A total of 101 adult patients who underwent TBI-based myeloablative conditioning for hematologic malignancies at Duke University between 1998 and 2008 were reviewed. TBI was combined with high-dose cyclophosphamide, melphalan, fludarabine, or etoposide, depending on the underlying disease. Acute pulmonary toxicity, occurring within 90 days of transplantation, was scored using Common Terminology Criteria for Adverse Events version 3.0. Actuarial overall survival and the cumulative incidence of acute pulmonary toxicity were calculated via the Kaplan-Meier method and compared using a log-rank test. A binary logistic regression analysis was performed to assess factors independently associated with acute severe pulmonary toxicity. Results: The 90-day actuarial risk of developing severe (Grade 3-5) pulmonary toxicity was 33%. Actuarial survival at 90 days was 49% in patients with severe pulmonary toxicity vs. 94% in patients without (p < 0.001). On multivariate analysis, the number of prior chemotherapy regimens was the only factor independently associated with development of severe pulmonary toxicity (odds ratio, 2.7 per regimen). Conclusions: Severe acute pulmonary toxicity is prevalent after TBI-based myeloablative conditioning regimens, occurring in approximately 33% of patients. The number of prior chemotherapy regimens appears to be an important risk factor.

  8. Developmental effects of exposures to environmental factors: the Polish Mother and Child Cohort Study.

    Science.gov (United States)

    Polanska, Kinga; Hanke, Wojciech; Sobala, Wojciech; Trzcinka-Ochocka, Malgorzata; Ligocka, Danuta; Brzeznicki, Slawomir; Strugala-Stawik, Halina; Magnus, Per

    2013-01-01

    This paper estimates the effects of exposure to environmental factors, including lead, mercury, environmental tobacco smoke (ETS), and polycyclic aromatic hydrocarbons (PAH), on child psychomotor development. The study population consists of mother-child pairs in the Polish Mother and Child Cohort Study. Prenatal and postnatal exposure to environmental factors was determined from biomarker measurements as follows: for lead exposure--cord blood lead level, for mercury--maternal hair mercury level, for ETS--cotinine level in saliva and urine, and for PAH--1-hydroxypyrene (1-HP) in urine. At the age of 12 (406 subjects) and 24 months (198 subjects) children were assessed using Bayley Scales of Infant and Toddler Development. There were no statistically significant effects of prenatal exposure to mercury or 1-HP on child psychomotor development. After adjusting for potential confounders, adverse effects of prenatal exposure to ETS on motor development ( β = -2.6; P = 0.02) and postnatal exposure to ETS on cognitive ( β = -0.2; P = 0.05) and motor functions ( β = -0.5; P = 0.01) were found. The adverse effect of prenatal lead exposure on cognitive score was of borderline significance ( β = -6.2; P = 0.06). The study underscores the importance of policies and public health interventions that aim to reduce prenatal and postnatal exposure to lead and ETS.

  9. Environmental Factors Influencing White-Tailed Deer (Odocoileus virginianus Exposure to Livestock Pathogens in Wisconsin.

    Directory of Open Access Journals (Sweden)

    Shelli Dubay

    Full Text Available White-tailed deer (Odocoileus virginianus are commonly exposed to disease agents that affect livestock but environmental factors that predispose deer to exposure are unknown for many pathogens. We trapped deer during winter months on two study areas (Northern Forest and Eastern Farmland in Wisconsin from 2010 to 2013. Deer were tested for exposure to six serovars of Leptospira interrogans (grippotyphosa, icterohaemorrhagiae, canicola, bratislava, pomona, and hardjo, bovine viral diarrhea virus (BVDV-1 and BVDV-2, infectious bovine rhinotracheitis virus (IBR, and parainfluenza 3 virus (PI3. We used logistic regression to model potential intrinsic (e.g., age, sex and extrinsic (e.g., land type, study site, year, exposure to multiple pathogens variables we considered biologically meaningful to exposure of deer to livestock pathogens. Deer sampled in 2010-2011 did not demonstrate exposure to BVDV, so we did not test for BVDV in subsequent years. Deer had evidence of exposure to PI3 (24.7%, IBR (7.9%, Leptospira interrogans serovar pomona (11.7%, L. i. bratislava (1.0%, L. i. grippotyphosa (2.5% and L. i. hardjo (0.3%. Deer did not demonstrate exposure to L. interrogans serovars canicola and icterohaemorrhagiae. For PI3, we found that capture site and year influenced exposure. Fawns (n = 119 were not exposed to L. i. pomona, but land type was an important predictor of exposure to L. i. pomona for older deer. Our results serve as baseline exposure levels of Wisconsin white-tailed deer to livestock pathogens, and helped to identify important factors that explain deer exposure to livestock pathogens.

  10. High incidence of hydrocephalus following prenatal exposure to X-irradiation at early gestational stage in mice

    International Nuclear Information System (INIS)

    Aolad, H.; Inouye, Minoru; Hayasaka, Shizu; Darmanto, W.; Murata, Yoshiharu

    1998-01-01

    Hydrocephalus is one of the severe brain anomalies. Several causes of congenital hydrocephalus have been reported and, it is known that radiation is one of those. The current study was designed to obtain postnatally viable hydrocephalic offspring at a high incidence following X-radiation. This finding will be helpful to elucidate the mechanism of congenital hydrocephalus caused by X-radiation. Twenty pregnant Slc:ICR mice, 5 in each group, were exposed to X-irradiation at a dose of 1.0 Gy on gestational days 7 (G7), G8, G9 or G10. The incidence of hydrocephalus was high in the group exposed on G7. An additional 21 pregnant mice were then exposed to a dose of 1.2 Gy, 1.3 Gy, 1.4 Gy or 1.5 Gy X-radiation on G7. The highest incidence of hydrocephalic offspring was found following exposure to 1.4 Gy X-radiation. (author)

  11. Determination of the axial thermal neutron flux non-uniform factor in the MNSR inner irradiation capsule

    International Nuclear Information System (INIS)

    Khattab, K.; Ghazi, N.; Omar, H.

    2007-01-01

    A 3-D neutronic model, using the WIMSD4 and CITATION codes, for the Syrian Miniature Neutron source Reactor (MNSR) is used to calculate the axial thermal neutron flux non-uniform factor in the inner irradiation capsule. The calculated result is 4%. A copper wire is used to measure the axial thermal neutron flux non-uniform factor in the inner irradiation capsule to be compared with the calculated result. The measured result is 5%. Good agreement between the measured and calculated results is obtained. (author)

  12. Determination of the axial thermal neutron flux non-uniform factor in the MNSR inner irradiation capsule

    International Nuclear Information System (INIS)

    Khattab, K.; Ghazi, N.; Omar, H.

    2007-01-01

    A 3-D neutronic model, using the WIMSD4 and CITATION codes, for the Syrian Miniature Neutron Source Reactor (MNSR) is used to calculate the axial thermal neutron flux non-uniform factor in the inner irradiation capsule. The calculated result is 4%. A copper wire is used to measure the axial thermal neutron flux non-uniform factor in the inner irradiation capsule to be compared with the calculated result. The measured result is 5%. Good agreement between the measured and calculated results is obtained

  13. Transportation of irradiated fuel elements

    International Nuclear Information System (INIS)

    1980-01-01

    A critique is presented of current methods of transporting spent nuclear fuel and the inadequacies of the associated contingency plans, with particular reference to the transportation of irradiated fuel through London. Anti-nuclear and pro-nuclear arguments are presented on a number of factors, including tests on flasks, levels of radiation exposure, routine transport arrangements and contingency arrangements. (U.K.)

  14. Exploring violence exposure, stress, protective factors and behavioral problems among inner-city youth.

    Science.gov (United States)

    Youngstrom, Eric; Weist, Mark D; Albus, Kathleen E

    2003-09-01

    This study examined relationships between violence exposure, other stressors, family support, and self-concept on self-reported behavioral problems among 320 urban adolescents (aged 11-18) referred for mental health treatment. Overall, participants reported high levels of violence exposure, with a median of six past encounters with violence as a witness, victim, or through the experiences of associates. All forms of violence exposure (witnessing, being a victim, knowing of victims) were correlated with internalizing and externalizing behavioral problems for males and females. Total violence exposure predicted behavioral problems among participants, even after controlling for the effects of other risk, demographic and protective factors. Family support and self-concept moderated the influence of life stress and cumulative risk on problem behavior outcomes, but these protective variables did not significantly moderate violence exposure.

  15. Self-reported noise exposure as a risk factor for long-term sickness absence

    DEFF Research Database (Denmark)

    Clausen, Thomas; Christensen, Karl Bang; Lund, Thomas

    2009-01-01

    men and women when adjusting for demographic factors and health behavior. After further adjustment for physical workload at work the association between noise exposure and sickness absence disappeared for women, but not for men. Men that reported to be exposed to loud noise between one......Self-reported noise exposure is on the rise in Denmark. Little is known, however, about the social consequences, including sickness absence, of noise exposure. The aim of this paper was to investigate the association between self-reported noise exposure and long-term sickness absence....... The association was investigated using the Cox proportional hazards model to analyze outcomes in Danish register data on the basis of Danish survey data (5357 employees aged 18-69 in 2000). The analyses showed that self-reported noise exposure was significantly associated with long-term sickness absence for both...

  16. Psychosocial factor exposures in the workplace: differences between immigrants and Spaniards.

    Science.gov (United States)

    Font, Ariadna; Moncada, Salvador; Llorens, Clara; Benavides, Fernando G

    2012-10-01

    The purpose of this study was to analyse psychosocial factor exposures in the workplace for immigrant workers in Spain and identify differences in exposure at work between immigrants and Spaniards. A multi-stage sample was taken by conglomerates (final sample size: 7555 workers). The information was obtained in 2004 and 2005 using a standardized questionnaire administered by interviewing participants in their homes. The analysis focused on eight psychosocial factors. For quantitative demands and insecurity, the exposure was defined according to the higher third, and for the others, the exposure was defined according to the lower third. The prevalence ratio (PR) and confidence interval (CI) for unfavourable psychosocial factor, both crude and adjusted, were calculated using log binomial models. Those with highest prevalence of unfavourable psychosocial factor were immigrant manual workers, particularly in low possibilities for development (PR=2.87; 95% CI 2.44-3.73), and immigrant women, particularly in low control over working times (PR=1.72; 95% CI 1.55-1.91). Immigrant workers with manual jobs and immigrant women are the groups most exposed to psychosocial factor. In efforts to prevent these exposures, these inequalities should be taken into account.

  17. Occupational exposure to organic solvents: a risk factor for pulmonary veno-occlusive disease.

    Science.gov (United States)

    Montani, David; Lau, Edmund M; Descatha, Alexis; Jaïs, Xavier; Savale, Laurent; Andujar, Pascal; Bensefa-Colas, Lynda; Girerd, Barbara; Zendah, Inès; Le Pavec, Jerome; Seferian, Andrei; Perros, Frédéric; Dorfmüller, Peter; Fadel, Elie; Soubrier, Florent; Sitbon, Oliver; Simonneau, Gérald; Humbert, Marc

    2015-12-01

    Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension characterised by predominant remodelling of pulmonary venules. Bi-allelic mutations in the eukaryotic translation initiation factor 2α kinase 4 (EIF2AK4) gene were recently described as the major cause of heritable PVOD, but risk factors associated with PVOD remain poorly understood. Occupational exposures have been proposed as a potential risk factor for PVOD, but epidemiological studies are lacking.A case-control study was conducted in consecutive PVOD (cases, n=33) and pulmonary arterial hypertension patients (controls, n=65). Occupational exposure was evaluated via questionnaire interview with blinded assessments using an expert consensus approach and a job exposure matrix (JEM).Using the expert consensus approach, PVOD was significantly associated with occupational exposure to organic solvents (adjusted OR 12.8, 95% CI 2.7-60.8), with trichloroethylene being the main agent implicated (adjusted OR 8.2, 95% CI 1.4-49.4). JEM analysis independently confirmed the association between PVOD and trichloroethylene exposure. Absence of significant trichloroethylene exposure was associated with a younger age of disease (54.8±21.4 years, p=0.037) and a high prevalence of harbouring bi-allelic EIF2AK4 mutations (41.7% versus 0%, p=0.015).Occupational exposure to organic solvents may represent a novel risk factor for PVOD. Genetic background and environmental exposure appear to influence the phenotypic expression of the disease. Copyright ©ERS 2015.

  18. Developmental Effects of Exposures to Environmental Factors: The Polish Mother and Child Cohort Study

    Directory of Open Access Journals (Sweden)

    Kinga Polanska

    2013-01-01

    Full Text Available This paper estimates the effects of exposure to environmental factors, including lead, mercury, environmental tobacco smoke (ETS, and polycyclic aromatic hydrocarbons (PAH, on child psychomotor development. The study population consists of mother-child pairs in the Polish Mother and Child Cohort Study. Prenatal and postnatal exposure to environmental factors was determined from biomarker measurements as follows: for lead exposure—cord blood lead level, for mercury—maternal hair mercury level, for ETS—cotinine level in saliva and urine, and for PAH—1-hydroxypyrene (1-HP in urine. At the age of 12 (406 subjects and 24 months (198 subjects children were assessed using Bayley Scales of Infant and Toddler Development. There were no statistically significant effects of prenatal exposure to mercury or 1-HP on child psychomotor development. After adjusting for potential confounders, adverse effects of prenatal exposure to ETS on motor development (β = −2.6; P=0.02 and postnatal exposure to ETS on cognitive (β = −0.2; P=0.05 and motor functions (β = −0.5; P=0.01 were found. The adverse effect of prenatal lead exposure on cognitive score was of borderline significance (β = −6.2; P=0.06. The study underscores the importance of policies and public health interventions that aim to reduce prenatal and postnatal exposure to lead and ETS.

  19. Influences of Pinpoint Plantar Long-Wavelength Infrared Light Irradiation (Stress-Free Therapy on Chorioretinal Hemodynamics, Atherosclerosis Factors, and Vascular Endothelial Growth Factor

    Directory of Open Access Journals (Sweden)

    Keisou Ishimaru

    2018-03-01

    Full Text Available Background: We previously reported that pinpoint plantar long-wavelength infrared light irradiation (stress-free therapy; SFT is useful for alleviating insulin resistance and improving intracranial blood flow in patients with type 2 diabetes mellitus. This study was undertaken to evaluate the influences of SFT on chorioretinal hemodynamics (retinal artery and vein blood flows as well as atherosclerosis-related factors (TG, LDL-C and VEGF in patients with dyslipidemia. Methods: Four patients with dyslipidemia received 15-minute irradiation with a stress-free apparatus (far-infrared wavelength, 30 mW. Using laser speckle flowgraphy, associations of chorioretinal blood flow with peripheral atherosclerosis-inducing factors/VEGF levels before and after irradiation were analyzed. Results: Chorioretinal blood flow increased, while TG/LDL-C levels decreased, after irradiation. VEGF tended to rise in cases with pre-irradiation baseline levels at the lower limit but tended to decrease in cases in which baseline levels had exceeded the normal range. Conclusion: SFT was suggested to enhance chorioretinal circulation and to normalize VEGF, thereby possibly contributing to amelioration of atherosclerosis-inducing factors. Abnormalities in chorioretinal hemodynamics are known to be highly involved in the pathophysiology of diabetic retinopathy and age-related macular degeneration, and anti-VEGF antibody has been used for treating these conditions. The necessity of risk management, involving chorioretinal blood flow, has been pointed out when dealing with central retinal vein occlusion, diabetes mellitus, ischemic cerebral/cardiac disease, dementia and so on. SFT is therefore a potential complementary medical strategy which can be expected to contribute to normalization of chorioretinal blood flow and atherosclerosis-inducing factors/VEGF levels, and thereby to the prevention of lifestyle-related chronic diseases. Keywords: Pinpoint plantar long

  20. Cells of the J774 macrophage cell line are primed for antibody-dependent cell-mediated cytotoxicity following exposure to γ-irradiation

    International Nuclear Information System (INIS)

    Duerst, R.; Werberig, K.

    1991-01-01

    Activation of macrophages (M phi) for host defense against tumor cells follows a sequence of priming events followed by an initiating stimulus that results in production and release of cytotoxic molecules that mediate target cell killing. The authors have developed a model to study specific macrophage cytotoxicity in vitro utilizing a cultured murine M phi cell line, J774. Specific cytotoxicity of cultured human gastrointestinal tumor cells is achieved in the presence of murine IgG2a monoclonal antibody (mAb) 17-1-A. The ability of these cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) is greatly enhanced following gamma-irradiation. ADCC can be demonstrated at mAb 17-1-A concentrations greater than or equal to 1 microgram/ml and effector/target cell ratios greater than or equal to 2. Exposure to doses greater than or equal to 10 Gy of gamma-irradiation increases ADCC threefold. Varying the duration from J774 M phi exposure to γ-irradiation until addition of antibody-coated target cells showed that the primed state for ADCC is stable for at least 8 days but approximately 24 hr is required for complete development of the primed state. mAb-dependent target cell death begins 8 hr after addition of mAb and labeled target cells to primed effector cells and is complete by 24 hr. Incubation of unirradiated J774 M phi effector cells with recombinant murine interferon-γ (rmIFN-γ) also results in enhanced ADCC, but the extent of target cell killing achieved is less than that following priming by γ-irradiation. Concomitant priming of γ-irradiated J774 M phi with rmIFN-γ increases the extent of ADCC. Further study of irradiated J774 cells may elucidate the molecular pathways utilized by M phi for achieving and maintaining the primed state for ADCC

  1. Upregulated epidermal growth factor receptor expression following near-infrared irradiation simulating solar radiation in a three-dimensional reconstructed human corneal epithelial tissue culture model

    Directory of Open Access Journals (Sweden)

    Tanaka Y

    2016-08-01

    Full Text Available Yohei Tanaka,1,2 Jun Nakayama2 1Department of Plastic Surgery, Clinica Tanaka Plastic, Reconstructive Surgery and Anti-aging Center, 2Department of Molecular Pathology, Shinshu University Graduate School of Medicine, Matsumoto, Nagano, Japan Background and objective: Humans are increasingly exposed to near-infrared (NIR radiation from both natural (eg, solar and artificial (eg, electrical appliances sources. Although the biological effects of sun and ultraviolet (UV exposure have been extensively investigated, the biological effect of NIR radiation is still unclear. We previously reported that NIR as well as UV induces photoaging and standard UV-blocking materials, such as sunglasses, do not sufficiently block NIR. The objective of this study was to investigate changes in gene expression in three-dimensional reconstructed corneal epithelial tissue culture exposed to broad-spectrum NIR irradiation to simulate solar NIR radiation that reaches human tissues.Materials and methods: DNA microarray and quantitative real-time polymerase chain reaction analysis were used to assess gene expression levels in a three-dimensional reconstructed corneal epithelial model composed of normal human corneal epithelial cells exposed to water-filtered broad-spectrum NIR irradiation with a contact cooling (20°C. The water-filter allowed 1,000–1,800 nm wavelengths and excluded 1,400–1,500 nm wavelengths.Results: A DNA microarray with >62,000 different probes showed 25 and 150 genes that were up- or downregulated by at least fourfold and twofold, respectively, after NIR irradiation. In particular, epidermal growth factor receptor (EGFR was upregulated by 19.4-fold relative to control cells. Quantitative real-time polymerase chain reaction analysis revealed that two variants of EGFR in human corneal epithelial tissue were also significantly upregulated after five rounds of 10 J/cm2 irradiation (P<0.05.Conclusion: We found that NIR irradiation induced the

  2. Factors associated with occupational exposure to biological material among nursing professionals.

    Science.gov (United States)

    Negrinho, Nádia Bruna da Silva; Malaguti-Toffano, Silmara Elaine; Reis, Renata Karina; Pereira, Fernanda Maria Vieira; Gir, Elucir

    2017-01-01

    to identify factors associated with occupational exposure to biological material among nursing professionals. a cross-sectional study was conducted in a high complexity hospital of a city in the state of São Paulo, Brazil. Nursing professionals were interviewed from March to November 2015. All ethical aspects were observed. among the 226 professionals interviewed, 17.3% suffered occupational exposure to potentially contaminated biological material, with 61.5% being percutaneous. Factors such as age (p=0.003), professional experience in nursing (p=0.015), and experience at the institution (p=0.032) were associated with the accidents with biological material. most accidents with biological material among nursing professionals were percutaneous. Age, professional experience, and experience at the institution were considered factors associated with occupational exposure.

  3. Effects of prolonged irradiation by low dose-rate ionizing radiation on the gene expression of hemopoietic factors of mice

    Energy Technology Data Exchange (ETDEWEB)

    Shirata, Katsutoshi; Saitou, Mikio; Yanai, Takanori; Sato, Fumiaki [Institute for Environmental Science, Rokkasho, Aomori (Japan)

    2000-07-01

    To evaluate the effect of prolonged low-dose irradiation on the gene expression of hemopoietic factors in tissues, gene expression was analyzed in the spleen as a hemopoietic tissue that is well known to be one of the most sensitive tissues to irradiation. SPF C3H/HeN female mice (Clea Japan Inc.) were irradiated under SPF conditions with {sup 137}Cs {gamma}-rays at doses of 2, 4, 6, and 8 Gy and a dose rate of 20 mGy/day. Non-irradiated mice of the same age were maintained as controls. At the end of the period of irradiation, both groups of mice were sacrificed and dissected to extract total RNA from their tissues. Reverse transcriptase-polymerase chain reaction (RT-PCR) and the Northern hybridization were employed to detect gene expression. RT-PCT showed no marked changes in the gene expression of GM-CSF. IL-6 gene expression was shown to tend to be enhanced by prolonged low-dose irradiation. The results of Northern hybridization showed that IL-6 mRNA was expressed slightly in both groups, and it was too weak to compare the difference in mRNA expression level between the irradiated group and the controls. No mRNA expression of GM-CSF was detected by Northern hybridization. Based on these results, it was concluded that the gene expression levels of IL-6 and GM-CSF were inadequate to detect the chemiluminescence signals without amplification. It was therefore concluded that improvement of detection sensitivity and larger RNA samples would be necessary for further analysis of the gene expression of hemopoietic factors. (K.H.)

  4. Therapeutic results and prognostic factors after irradiation of loco-regional prostate cancer

    International Nuclear Information System (INIS)

    Debrigode, C.; Dubois, J.; Hay, H.M.; Astre, C.; Savu, N.M.

    1994-01-01

    The present study concerns 140 patients with loco-regional prostatic cancer, treated with external beam irradiation at the CRLC Val-d'Aurelle in Montpellier, France, between 1982 and 1988, with a minimum of 54 months follow-up. The local control after radiotherapy is 78.6%, all stages and histological grades combined. The median overall survival is 114 months and the median disease-free survival 59 months. The most frequent modality of treatment failure is metastatic disease, isolated (32.8%) or combined to local relapse (10%). The rate of urinary intolerance symptoms during treatment was 87.1 and 80.6% for the digestive ones. The late urinary complications and sequellae rate was 21.4% for the cystitis-type and 12.9% for post-radiotherapy urethral structures; the latter has imposed in 2/3 of cases one or more trans-urethral resections that never showed pathological signs of recurrence. Digestive complications and sequellae occurred in 31.3% of the patients; in the latter group there were two internal digestive fistulae which needed surgical treatment and three postradiotherapeutic stenosis of the anal canal. The prognostic factors revealed by statistical analysis are clinical stage, pathological grade for overall and disease-free survival, age for overall survival and trans-urethral resection for disease-free survival, the latter being equally a risk factor for cystitis-type complications and urethral structures. (authors). 26 refs., 8 figs., 7 tabs

  5. Factors associated with pulmonary toxicity after myeloablative conditioning using fractionated total body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Hwa Kyung; Yoon, Hong In; Cho, Jae Ho [Yonsei Cancer Center, Yonsei University College of Medicine, Seoul (Korea, Republic of); and others

    2017-09-15

    Pulmonary toxicities, including infectious pneumonia (IP) and idiopathic pneumonia syndrome (IPS), are serious side effects of total body irradiation (TBI) used for myeloablative conditioning. This study aimed to evaluate clinical factors associated with IP and IPS following TBI. Fifty-eight patients with hematologic malignancies who underwent TBI before allogeneic hematopoietic stem cell transplantation between 2005 and 2014 were reviewed. Most patients (91%) received 12 Gy in 1.5 Gy fractions twice a day. Pulmonary toxicities were diagnosed based on either radiographic evidence or reduced pulmonary function, and were subdivided into IP and IPS based on the presence or absence of concurrent infection. Pulmonary toxicities developed in 36 patients (62%); 16 (28%) had IP and 20 (34%) had IPS. IP was significantly associated with increased treatment-related mortality (p = 0.028) and decreased survival (p = 0.039). Multivariate analysis revealed that the risk of developing IPS was significantly higher in patients who received stem cells from a matched unrelated donor than from a matched sibling donor (p = 0.021; hazard ratio [HR] = 12.67; 95% confidence interval [CI], 1.46–110.30). Combining other conditioning agents with cyclophosphamide produced a higher tendency to develop IP (p = 0.064; HR = 6.19; 95% CI, 0.90–42.56). IP and IPS involve different risk factors and distinct pathogeneses that should be considered when planning treatments before and after TBI.

  6. Ion-recombination correction factor κsat for spherical ion chambers irradiated by continuous photom beams

    International Nuclear Information System (INIS)

    Piermattei, A.; Azario, L.; Arcovito, G.

    1996-01-01

    The large range of reference air kerma rates of brachytherapy sources involves the use of large-volume ionization chambers. When such ionization chambers are used the ion-recombination correction factor k sat has to be determined. In this paper three spherical ion chambers with volume ranging from 30 to 10 4 cm 3 have been irradiated by photons of a 192 Ir source to determine the k sat factors. The ionization currents of the ion chambers as a function of the applied voltage and the air kerma rate have been analysed to determine the contribution of the initial and general ion recombination. The k sat values for large-volume ionization chambers obtained by considering the general ion recombination as predominant (Almond's approach) are in disagreement with the results obtained using methods that consider both initial and general ion-recombination contributions (Niatel's approach). Such disagreement can reach 0.7% when high currents are measured for a high-activity source calibration in terms of reference air kerma rate. In this study a new 'two-voltage' method, independent of the voltage ratio given by a dosimetry system, is proposed for practical dosimetry of continuous x-and gamma-radiation beams. In the case where the Almond approach is utilized, the voltage ratio V 1 /V 2 should be less than 2 instead of Almond's limit of V 1 /V 2 <5. (Author)

  7. Factors associated with pulmonary toxicity after myeloablative conditioning using fractionated total body irradiation

    International Nuclear Information System (INIS)

    Byun, Hwa Kyung; Yoon, Hong In; Cho, Jae Ho

    2017-01-01

    Pulmonary toxicities, including infectious pneumonia (IP) and idiopathic pneumonia syndrome (IPS), are serious side effects of total body irradiation (TBI) used for myeloablative conditioning. This study aimed to evaluate clinical factors associated with IP and IPS following TBI. Fifty-eight patients with hematologic malignancies who underwent TBI before allogeneic hematopoietic stem cell transplantation between 2005 and 2014 were reviewed. Most patients (91%) received 12 Gy in 1.5 Gy fractions twice a day. Pulmonary toxicities were diagnosed based on either radiographic evidence or reduced pulmonary function, and were subdivided into IP and IPS based on the presence or absence of concurrent infection. Pulmonary toxicities developed in 36 patients (62%); 16 (28%) had IP and 20 (34%) had IPS. IP was significantly associated with increased treatment-related mortality (p = 0.028) and decreased survival (p = 0.039). Multivariate analysis revealed that the risk of developing IPS was significantly higher in patients who received stem cells from a matched unrelated donor than from a matched sibling donor (p = 0.021; hazard ratio [HR] = 12.67; 95% confidence interval [CI], 1.46–110.30). Combining other conditioning agents with cyclophosphamide produced a higher tendency to develop IP (p = 0.064; HR = 6.19; 95% CI, 0.90–42.56). IP and IPS involve different risk factors and distinct pathogeneses that should be considered when planning treatments before and after TBI

  8. Normal and sublethally irradiated stem and granulocyte progenitor cell regeneration in an in vivo culture system. The cellular response to humoral factors released through the action of cyclophosphamide

    International Nuclear Information System (INIS)

    MacVittie, T.

    1977-01-01

    The in vivo diffusion chamber (DC) method of marrow culture was used to determine if the injection of host mice with cyclophosphamide (CY) caused, through its cytoxic action, the release of a humoral factor(s) capable of initiating stem cell (CFU-s) and granulocyte-macrophage progenitor cell (CFU-c) proliferation. Host mice were injected with CY 1-4 days prior to 800 rad of 60 Co WBI and implantation of DCs containing normal or 400 rad sublethally irradiated (SLI) marrow cells. The greatest proliferative response within CFU-s and CFU-c populations occurred in those mice injected with CY 3 days prior to implant. The marked CFU-s and CFU-c regeneration was initiated during the initial 24 hr of culture in both normal and SLI marrow cells. Thereafter growth rates were approximately the same. SLI marrow, however, showed a greater response to the humoral effects of CY injection than did normal marrow. These data provided evidence that CY induced the release of a diffusible factor(s) capable of accelerating regeneration of normal and sublethally irradiated CFU-s and CFU-c, the magnitude of which was dependent upon the time elapsed between CY injected and implantation of DCs. The marked proliferative response of the SLI stem and progenitor cells to the humoral stimulation may be indicative of the heterogeneity of both CFU-s and CFU-c populations surviving sublethal radiation exposure. The target cells may have possessed a differential sensitivity to the factor(s) initiating cell proliferation

  9. Aggregate Exposure and Cumulative Risk Assessment--Integrating Occupational and Non-occupational Risk Factors.

    Science.gov (United States)

    Lentz, T J; Dotson, G S; Williams, P R D; Maier, A; Gadagbui, B; Pandalai, S P; Lamba, A; Hearl, F; Mumtaz, M

    2015-01-01

    Occupational exposure limits have traditionally focused on preventing morbidity and mortality arising from inhalation exposures to individual chemical stressors in the workplace. While central to occupational risk assessment, occupational exposure limits have limited application as a refined disease prevention tool because they do not account for all of the complexities of the work and non-occupational environments and are based on varying health endpoints. To be of greater utility, occupational exposure limits and other risk management tools could integrate broader consideration of risks from multiple exposure pathways and routes (aggregate risk) as well as the combined risk from exposure to both chemical and non-chemical stressors, within and beyond the workplace, including the possibility that such exposures may cause interactions or modify the toxic effects observed (cumulative risk). Although still at a rudimentary stage in many cases, a variety of methods and tools have been developed or are being used in allied risk assessment fields to incorporate such considerations in the risk assessment process. These approaches, which are collectively referred to as cumulative risk assessment, have potential to be adapted or modified for occupational scenarios and provide a tangible path forward for occupational risk assessment. Accounting for complex exposures in the workplace and the broader risks faced by the individual also requires a more complete consideration of the composite effects of occupational and non-occupational risk factors to fully assess and manage worker health problems. Barriers to integrating these different factors remain, but new and ongoing community-based and worker health-related initiatives may provide mechanisms for identifying and integrating risk from aggregate exposures and cumulative risks from all relevant sources, be they occupational or non-occupational.

  10. Assessment of relevant factors and relationships concerning human dermal exposure to pesticides in greenhouse applications.

    Science.gov (United States)

    Martínez Vidal, Jose L; Egea González, Francisco J; Garrido Frenich, Antonia; Martínez Galera, María; Aguilera, Pedro A; López Carrique, Enrique

    2002-08-01

    Principal component analysis (PCA) was applied to the gas chromatographic data obtained from 23 different greenhouse trials. This was used to establish which factors, including application technique (very small, small, medium and large drop-size), crop characteristics (short/tall, thin/dense) and pattern application of the operator (walking towards or away from the treated area) are relevant to the dermal exposure levels of greenhouse applicators. The results showed that the highest exposure by pesticides during field applications in greenhouses, in the climatic conditions and in the crop conditions typical of a southern European country, occurs on the lower legs and front thighs of the applicators. Similar results were obtained by hierarchical cluster analysis (HCA). Drop-size seems to be very important in determining total exposure, while height and density of crops have little influence on total exposure under the conditions of the present study. No pesticide type is a major factor in total exposure. The application of multiple regression analysis (MRA) allowed assessment of the relationships between the pesticide exposure of the less affected parts of the body with the most affected parts.

  11. Risk factors for tube exposure as a late complication of glaucoma drainage implant surgery

    Directory of Open Access Journals (Sweden)

    Chaku M

    2016-03-01

    Full Text Available Meenakshi Chaku,1 Peter A Netland,2 Kyoko Ishida,3 Douglas J Rhee4 1Department of Ophthalmology, Loyola University Chicago, Maywood, IL, 2Department of Ophthalmology, University of Virginia School of Medicine, Charlottesville, VA, USA; 3Department of Ophthalmology, Toho University, Tokyo, Japan; 4Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH, USA Purpose: The purpose of this study was to evaluate the risk factors for tube exposure after glaucoma drainage implant surgery.Patients and methods: This was a retrospective case-controlled observational study of 64 eyes from 64 patients. Thirty-two eyes of 32 patients with tube erosion requiring surgical revision were compared with 32 matched control eyes of 32 patients. Univariate and multivariate risk factor analyses were performed.Results: Mean age was significantly younger in the tube exposure group compared with the control group (48.2±28.1 years versus 67.3±18.0 years, respectively; P=0.003. The proportion of diabetic patients (12.5% in the tube exposure group was significantly less (P=0.041 compared with the control group (37.5%. Comparisons of the type and position of the drainage implant were not significantly different between the two groups. The average time to tube exposure was 17.2±18.0 months after implantation of the drainage device. In both univariate and multivariate analyses, younger age (P=0.005 and P=0.027 and inflammation prior to tube exposure (P≤0.001 and P=0.004 were significant risk factors. Diabetes was a significant risk factor only in the univariate analysis (P=0.027.Conclusion: Younger age and inflammation were significant risk factors for tube exposure after drainage implant surgery. Keywords: glaucoma drainage implant complications, Ahmed Glaucoma Valve, Baerveldt implant, tube erosion, pericardial patch graft

  12. Risk factors related to interfractional variation in whole pelvic irradiation for locally advanced pelvic malignancies

    International Nuclear Information System (INIS)

    Yoon, W.S.; Yang, D.S.; Lee, J.A.; Lee, S.; Park, Y.J.; Kim, C.Y.

    2012-01-01

    Purpose: The goal of the present study was to demonstrate risk factors affecting the interfractional variation in whole pelvic irradiation. Patients and methods: Daily image acquisitions of 101 patients with locally advanced pelvic malignancy were undertaken using a kilo-voltage orthogonal on-board imager. The baseline deviation (the shift between the initial treatment and each fraction; Value Base ) and day-to-day variation (the shift between the previous treatment and each fraction; Value DD ) were measured. The standard deviations (SD) along the x- (right-left), y- (cranial-caudal), and z- (anterior-posterior) axes (SD[x], SD[y], and SD[z], respectively), the 3D vector of the SD (SD[3D]), and the mean of 3D shift (mean[3D]) were calculated in each patient. Various clinical factors, lumbar pelvic balance and rotation, and the shift of 5 consecutive fractions from the initial treatment (Value 5Fx ) were investigated as risk factors. Results: The prone set-up showed a larger mean Base [3D] than in the supine position (p =0.063). A body mass index (BMI) ≥ 30 kg/m 2 resulted in the largest mean DD [3D] (p = 0.078) and SD DD [3D] (p = 0.058). All the SD 5Fx along the x-, y-, and z-axes had moderate linear relationships with SD Base and SD DD (p 5Fx [3D] also had a moderate linear relationship with the mean Base [3D], mean DD [3D], SD Base [3D], and SD DD [3D] (p 5Fx had the same significant relationship with SD Base and SD DD (p 2 was associated with the largest SD DD [x] (p = 0.003). Conclusion: Close surveillance through high-quality and frequent image guidance is recommended for patients with extensive variations of the initial five consecutive fractions or obesity. (orig.)

  13. An ignored risk factor in toxicology: The total imprecision of exposure assessment

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Budtz-Jørgensen, Esben

    2010-01-01

    twice as much for maternal hair. The total imprecision of these biomarkers much exceeded the normal laboratory variability of less than 5%. Such imprecision can cause underestimation of dose-related toxicity, and data analysis should therefore include sensitivity analyses that take this factor...... were determined in cord blood, cord tissue, and maternal hair. We determined their mutual correlations and their associations with the child's neurobehavioral effect variables at age 7 years. The exposure biomarkers correlated well with one another, but the cord blood mercury concentration showed......Quality assurance of exposure biomarkers usually focuses on laboratory performance only. Using data from a prospective birth cohort study in the Faroe Islands, we have assessed the total imprecision of exposure biomarkers. As biomarkers of prenatal methylmercury exposure, mercury concentrations...

  14. Dose factors to calculate the radiation exposure due to radioactive waste air from nuclear facilities

    International Nuclear Information System (INIS)

    Brenk, H.D.; Vogt, K.J.

    1977-01-01

    An evaluation of the environmental impact of nuclear plants according to paragraph 45 of the Radiation Protection Directive of the Federal Republic of Germany requires the calculation of dose conversion factors indicating the correlation between the contaminated medium and individual radiation exposure. The present study is to be conceived as a contribution to discussion on this subject. For the determination of radiation exposure caused by the waste air of nuclear plants, models are being specified for computing the dose conversion factors for the external exposure pathways of β-submersion, γ-submersion and γ-radiation from contaminated ground as well as the internal exposure pathways of inhalation and ingestion, which further elaborate and improve the models previously applied, especially as far as the ingestion pathway is concerned, which distinguishes between 6 major food categories. The computer models are applied to those radionuclides which are significan for nuclear emitters, in particular nuclear light-water power stations. The results obtained for the individual exposure pathways and affected organs are specified in the form of tables. For this purpose, calculations were first of all carried out for the so-called 'reference man'. The results can be transferred to population groups with different consumption habits (e.g. vegetarians) by the application of correction factors. The models are capable of being extended with a view to covering other age groups. (orig.) [de

  15. Dependence of the postirradiation lymphopenia and hypersegmentation of neutrophil nuclei on the therapeutic irradiation exposure in patients with breast carcinoma--some ways of its use for biological detection of irradiation.

    Science.gov (United States)

    Zák, M; Rezný, Z; Uhlírová, A; Bednárová, Z; Lintner, L; Benes, J

    1978-12-01

    In the work, changes are presented of the numbers of lymphocytes and hypersegmented neutrophils after therapeutic irradiation of women after mastectomy. The values found were evaluated statistically by the decision method. It was found that in the course of irradiation the lymphopenia and increase in the number of neutrophils with hypersegmented cellular nuclei occurred. This contraversory course of the values showed an increasing tendency with increasing exposure. An attempt was made, whether the values found could serve for the biological detection if irradiation, when completing the response of the organism to irradiation based on changes of one parameter by a response from changes of second parameter examined. The values were used as training material for the statistical decision method. The results are represented in the from of a diagram for reading off the magnitude of the damage in practice by stimultaneous evaluation of both parameters. A further approach is shown in the biological dosimetry by simultaneous examination of several independent paramters statistically treated by a suitable method.

  16. Anti-nutritional Factors and Ruminal Dry Matter and Crude Protein Degradability of Gamma and Microwave Irradiated Native Rapeseed

    Directory of Open Access Journals (Sweden)

    sayyed roohollah ebrahimimahmoudabad

    2016-08-01

    Full Text Available Introduction Native rapeseed (NRS is planted in some parts of Iran because of climatic condition. The consumption of NRS in animal nutrition is limited by anti-nutritional such as phytic acid and glucosinolate. Moreover, the protein of NRS is highly degraded by rumen microorganisms. Several processing methods have been used to enhance the nutritive value of whole oilseeds, including extrusion, roasting, toasting and Jet-Sploding. However, most heat processing methods adversely affect protein digestibility in the small intestine. Recently, other processing methods such as processing by gamma and microwave irradiation have been noticed. Therefore, this research was carried out to evaluate the effects of gamma irradiation (15, 30 and 45 kGy and microwave irradiation (800 W for 2, 4 and 6 min on ruminal dry matter (DM and crude protein (CP degradability, in vitro CP digestibility, anti-nutritional factors (glucosinolate and phytic acid and chemical composition of NRS. Materials and Methods Chemical composition (DM, CP, EE and Ash of untreated and irradiated NRS was determined by AOAC methods. Then, sufficient water was added to the sample to increase the moisture content to 250 g/kg. Gamma irradiation was completed by using a cobalt-60 irradiator at 20 ºC. The dose rate determined by Fricke dosimetry was 0.36 Gy/s. Another three samples (500 g each were subjected to microwave irradiation at a power of 800 W for 2, 4 and 6 min. Phytic acid and glucosinolate contents of untreated and irradiated samples were determined by standard methods. Degradation kinetics of DM or CP were determined according to in situ procedure. Six grams of untreated or irradiated NRS were incubated in the rumen of three ruminally fistulated Taleshi bulls for 0, 2, 4, 8, 16, 24 and 48 h. Bags were placed in the rumen just before the bulls were offered their first meal. After retrieval from the rumen, bags were thoroughly washed with tap water until the rinsing water was clear

  17. Studies on mechanism of treatment of granulocyte colony-stimulating factor, recombinant human interleukin-11 and recombinant human interleukin-2 on hematopoietic injuries induced by 4.5 Gy γ-rays irradiation in beagles

    International Nuclear Information System (INIS)

    Li Ming; Ou Hongling; Xing Shuang; Huang Haixiao; Xiong Guolin; Xie Ling; Zhao Yanfang; Zhao Zhenhu; Wang Ning; Wang Jinxiang; Miao Jingcheng; Zhu Nankang; Luo Qingliang; Cong Yuwen; Zhang Xueguang

    2010-01-01

    Objective: To investigate the mechanism of treatment of granulocyte colony-stimulating factor (rhG-CSF), recombinant human interleukin-11 (rhIL-11) and recombinant human interleukin-2 (rhIL-2) on hematopoietic injuries induced by 4.5 Gy 60 Co γ-ray irradiation in beagles, and to provide experimental evidence for the clinical treatment of extremely severe myeloid acute radiation sickness (ARS). Methods: Sixteen beagle dogs were given 4.5 Gy 60 Co γ-ray total body irradiation (TBI), then randomly assigned into irradiation control group, supportive care group or cytokines + supportive care (abbreviated as cytokines) group. In addition to supportive care, rhG-CSF, rhIL-11 and rhIL-2 were administered subcutaneously to treat dogs in cytokines group. The percentage of CD34 + cells, cell cycle and apoptosis of nucleated cells in peripheral blood were examined by Flow cytometry. Results: After 4.5 Gy 60 Co γ-ray irradiation, the CD34 + cells in peripheral blood declined obviously (61.3% and 52.1% of baseline for irradiation control and supportive care group separately). The cell proportion of nucleated cells in G 0 /G 1 phase was increased notably notably (99.27% and 99.49% respectively). The rate of apoptosis (26.93% and 21.29% separately) and necrosis (3.27% and 4.14%, respectively) of nucleated cells were elevated significantly when compared with values before irradiation (P 0 /G 1 phase blockage of nucleated cells became more serious (99.71%). The rate of apoptosis (5.66%) and necrosis (1.60%) of nucleated cells were significantly lower than that of irradiation control and supportive care groups 1 d after exposure. Conclusions: Cytokines maybe mobilize CD34 + cells in bone marrow to peripheral blood, indce cell block at G 0 /G 1 phase and reduce apoptosis, and eventually cure hematopoietic injuries induced by irradiation. (authors)

  18. Street characteristics and traffic factors determining road users' exposure to black carbon

    International Nuclear Information System (INIS)

    Dons, Evi; Temmerman, Philip; Van Poppel, Martine; Bellemans, Tom; Wets, Geert; Int Panis, Luc

    2013-01-01

    Many studies nowadays make the effort of determining personal exposure rather than estimating exposure at the residential address only. While intra-urban air pollution can be modeled quite easily using interpolation methods, estimating exposure in transport is more challenging. The aim of this study is to investigate which factors determine black carbon (BC) concentrations in transport microenvironments. Therefore personal exposure measurements are carried out using portable aethalometers, trip diaries and GPS devices. More than 1500 trips, both by active modes and by motorized transport, are evaluated in Flanders, Belgium. GPS coordinates are assigned to road segments to allow BC concentrations to be linked with trip and road characteristics (trip duration, degree of urbanization, road type, traffic intensity, travel speed and road speed). Average BC concentrations on highways (10.7 μg/m 3 ) are comparable to concentrations on urban roads (9.6 μg/m 3 ), but levels are significantly higher than concentrations on rural roads (6.1 μg/m 3 ). Highways yield higher BC exposures for motorists compared to exposure on major roads and local roads. Overall BC concentrations are elevated at lower speeds ( 3 for roads with less than 500 veh/h, up to 12 μg/m 3 for roads with over 2500 veh/h). Traffic intensity proved to be the major explanatory variable for in-vehicle BC exposure, together with timing of the trip and urbanization. For cyclists and pedestrians the range in BC exposure is smaller and models are less predictive; for active modes exposure seems to be influenced by timing and degree of urbanization only. - Highlights: ► Aethalometers, an electronic diary and GPS were used to measure exposure in transport ► More than 1500 trips with active modes and in motorized transport are studied ► Exposure is higher on highways, in urban areas and during traffic peak hours. ► Traffic intensity is the major explanatory variable for in-vehicle BC exposure. ► Exposure

  19. The transplantation of neural stem cells and predictive factors in hematopoietic recovery in irradiated mice.

    Science.gov (United States)

    Filip, S; Mokrý, J; Karbanová, J; Vávrová, J; Vokurková, J; Bláha, M; English, D

    2005-04-01

    A number of surprising observations have shown that stem cells, in suitable conditions, have the ability to produce a whole spectrum of cell types, regardless, whether these tissues are derived from the same germ layer or not. This phenomenon is called stem cell plasticity, which means that tissue-specific stem cells are mutually interchangeable. In our experiments, as a model, we used neural stem cells (NSCs) harvested from fetal (E14-15) neocortex and beta-galactosidase positive. In the first experiment we found that on days 12 and 30 after sub-lethal irradiation (LD 8.5 Gy) and (beta-galactosidase(+)) NSCs transplantation all mice survived, just as the group with bone marrow transplantation. Moreover, the bone marrow of mice transplanted NSCs contained the number of CFU-GM colonies with beta-galactosidase(+) cells which was as much as 50% higher. These differences were statistically significant, pthird experiment, we verified the mutual interchange of Sca-1 surface antigen in the bone marrow cells and NSCs before transplantation. Analysis of this antigen showed 24.8% Sca-1 positive cells among the bone marrow cells, while NSCs were Sca-1 negative. Our experiments show that NSCs share hemopoietic identity and may significantly influence the recovery of damaged hematopoiesis but do not have typical superficial markers as HSCs. This result is important for the determination of predictive factors for hemopoiesis recovery, for stem cell plasticity and for their use in the cell therapy.

  20. Physical Activity, a Critical Exposure Factor of Environmental Pollution in Children and Adolescents Health Risk Assessment.

    Science.gov (United States)

    Dong, Jingmei; Zhang, Su; Xia, Li; Yu, Yi; Hu, Shuangshuang; Sun, Jingyu; Zhou, Ping; Chen, Peijie

    2018-01-23

    It is an extremely urgent problem that physical fitness promotion must face not only the increasing air pollution but also the decline of physical activity level of children and adolescents worldwide at present, which is the major reason that forms an inactive lifestyle and does harm to adolescents' health. Thus, it is necessary to focus on the exposure factor in environmental health risk assessment (EHRA) which conducts supervision of environmental pollution and survey of adolescents' activity patterns according to the harmful characteristics of air pollutant and relationship between dose and response. Some countries, such as USA, Canada and Australia, regard both respiratory rate and physical activity pattern as main exposure factors for adolescents in both air pollution health risk assessment and exercise risk assessment to forecast a safe exposing condition of pollutant for adolescents while they are doing exercise outdoors. In addition, it suggests that the testing indexes and testing methods of these two exposure factors, such as investigating the time of daily physical activity, strength, and characteristic of frequency, help to set up the quantitative relationship between environmental pollution index and the time, strength, frequency of daily activities, and formulate children's and adolescents' activity instructions under different levels of environmental pollutions. As smog becomes increasingly serious at present, it is meaningful to take physical activity as a critical composition of exposure factor and establish physical activity guideline, so as to reduce the risk of air pollution, and promote physical health of children and adolescents effectively.

  1. Exposure to Political Conflict and Violence and Posttraumatic Stress in Middle East Youth: Protective Factors

    Science.gov (United States)

    Dubow, Eric F.; Huesmann, L. Rowell; Boxer, Paul; Landau, Simha; Dvir, Shira; Shikaki, Khalil; Ginges, Jeremy

    2012-01-01

    We examine the role of family- and individual-level protective factors in the relation between exposure to ethnic-political conflict and violence and posttraumatic stress among Israeli and Palestinian youth. Specifically, we examine whether parental mental health (lack of depression), positive parenting, children's self-esteem, and academic…

  2. Aging: Characteristics, Exposure Factors, Epigenetics, and Assessment of Health Risks of Older Adults

    Science.gov (United States)

    This chapter is organized into three sections. The first part describes the characteristics of the older adult population and the U.S. EPA’s efforts to protect elders form environmental hazards. Section II covers available exposure factor data, activity pattern and the pot...

  3. Physical Activity, a Critical Exposure Factor of Environmental Pollution in Children and Adolescents Health Risk Assessment

    Science.gov (United States)

    Zhang, Su; Xia, Li; Yu, Yi; Hu, Shuangshuang; Sun, Jingyu; Zhou, Ping; Chen, Peijie

    2018-01-01

    It is an extremely urgent problem that physical fitness promotion must face not only the increasing air pollution but also the decline of physical activity level of children and adolescents worldwide at present, which is the major reason that forms an inactive lifestyle and does harm to adolescents’ health. Thus, it is necessary to focus on the exposure factor in environmental health risk assessment (EHRA) which conducts supervision of environmental pollution and survey of adolescents’ activity patterns according to the harmful characteristics of air pollutant and relationship between dose and response. Some countries, such as USA, Canada and Australia, regard both respiratory rate and physical activity pattern as main exposure factors for adolescents in both air pollution health risk assessment and exercise risk assessment to forecast a safe exposing condition of pollutant for adolescents while they are doing exercise outdoors. In addition, it suggests that the testing indexes and testing methods of these two exposure factors, such as investigating the time of daily physical activity, strength, and characteristic of frequency, help to set up the quantitative relationship between environmental pollution index and the time, strength, frequency of daily activities, and formulate children’s and adolescents’ activity instructions under different levels of environmental pollutions. As smog becomes increasingly serious at present, it is meaningful to take physical activity as a critical composition of exposure factor and establish physical activity guideline, so as to reduce the risk of air pollution, and promote physical health of children and adolescents effectively. PMID:29360730

  4. Community Violence Exposure and Adolescent Delinquency: Examining a Spectrum of Promotive Factors

    Science.gov (United States)

    Chen, Pan; Voisin, Dexter R.; Jacobson, Kristen C.

    2016-01-01

    This study examined whether promotive factors (future expectations, family warmth, school attachment, and neighborhood cohesion) moderated relationships between community violence exposure and youth delinquency. Analyses were conducted using N = 2,980 sixth to eighth graders (M[subscript age] = 12.48; 41.1% males) from a racially, ethnically, and…

  5. Physical Activity, a Critical Exposure Factor of Environmental Pollution in Children and Adolescents Health Risk Assessment

    Directory of Open Access Journals (Sweden)

    Jingmei Dong

    2018-01-01

    Full Text Available It is an extremely urgent problem that physical fitness promotion must face not only the increasing air pollution but also the decline of physical activity level of children and adolescents worldwide at present, which is the major reason that forms an inactive lifestyle and does harm to adolescents’ health. Thus, it is necessary to focus on the exposure factor in environmental health risk assessment (EHRA which conducts supervision of environmental pollution and survey of adolescents’ activity patterns according to the harmful characteristics of air pollutant and relationship between dose and response. Some countries, such as USA, Canada and Australia, regard both respiratory rate and physical activity pattern as main exposure factors for adolescents in both air pollution health risk assessment and exercise risk assessment to forecast a safe exposing condition of pollutant for adolescents while they are doing exercise outdoors. In addition, it suggests that the testing indexes and testing methods of these two exposure factors, such as investigating the time of daily physical activity, strength, and characteristic of frequency, help to set up the quantitative relationship between environmental pollution index and the time, strength, frequency of daily activities, and formulate children’s and adolescents’ activity instructions under different levels of environmental pollutions. As smog becomes increasingly serious at present, it is meaningful to take physical activity as a critical composition of exposure factor and establish physical activity guideline, so as to reduce the risk of air pollution, and promote physical health of children and adolescents effectively.

  6. The effects of exposure to environmental factors on Heart Rate Variability: An ecological perspective

    International Nuclear Information System (INIS)

    Schnell, Izhak; Potchter, Oded; Epstein, Yoram; Yaakov, Yaron; Hermesh, Hagai; Brenner, Shmuel; Tirosh, Emanuel

    2013-01-01

    The impact of human exposure to environmental factors on Heart Rate Variability (HRV) was examined in the urban space of Tel-Aviv-Jaffa. Four environmental factors were investigated: thermal and social loads; CO concentrations and noise. Levels of HRV are explained mainly by subjective social stresses, noise and CO. The most interesting result is the fact that while subjective social stress and noise increase HRV, low levels of CO are reducing HRV to some extent moderating the impact of subjective social stress and noise. Beyond the poisoning effect of CO and the fact that extremely low levels of HRV associated with high dozes of CO increase risk for life, low levels of CO may have a narcotic effect, as it is measured by HRV. The effects of thermal loads on HRV are negligible probably due to the use of behavioral means in order to neutralize heat and cold effects. -- Highlights: ► The impact of human exposure to environmental factors on Heart Rate Variability (HRV) was examined. ► Previous studies measured human exposure to pollution by fixed monitoring stations. ► This study measured actual personal exposure by mini sensors. ► High level of subjective social load and noise increase HRV. ► Low levels of CO may have a narcotic effect, as it is measured by HRV. -- The research focuses on the effects of environmental factors; noise, subjective social stress, thermal load and CO on Heart Rate Variability

  7. Investigation of electron beam irradiation effects on anti-nutritional factors, chemical composition and digestion kinetics of whole cottonseed, soybean and canola seeds

    International Nuclear Information System (INIS)

    Ebrahimi-Mahmoudabad, S.R.; Taghinejad-Roudbaneh, M.

    2011-01-01

    This study was completed to determine effects of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on anti-nutritional factors, ruminal degradation and in vitro crude protein (CP) digestibility of whole cottonseed (WCS), soybean (SB) and canola seeds (CS). EB-irradiation eliminated completely (P<0.001) phytic acid of WCS, SB and CS at a dose of 30 kGy. EB-irradiation decreased linearly (P<0.001) the total glucosinolate content of CS. Trypsin inhibitor activity of 15, 30 and 45 kGy EB-irradiated SB was decreased by 19, 73 and 88%, respectively. Free gossypol content of WCS was reduced linearly (P<0.001) by irradiation. EB-irradiation increased linearly (P<0.001) CP digestibility of feeds. In conclusion, EB-irradiation was an effective processing method for improving the nutritive value of WCS, SB and CS. - Highlights: → Effects of electron beam (EB) irradiation on nutritive value of some oilseeds were evaluated. → EB-irradiation eliminated completely phytic acid of seeds at a dose of 30 kGy. → EB-irradiation decreased trypsin inhibitor activity of soybean. → Free gossypol content of whole cottonseed was reduced linearly by EB-irradiation. → EB-irradiation increased escape protein and crude protein digestibility of seeds.

  8. Investigation of electron beam irradiation effects on anti-nutritional factors, chemical composition and digestion kinetics of whole cottonseed, soybean and canola seeds

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi-Mahmoudabad, S.R., E-mail: ebrahimiyazd@yahoo.com [Department of Animal Science, Faculty of Agriculture, Shahr-e-Qods Branch, Islamic Azad University, P.O. Box 37515-374, Shahr-e-Qods (Iran, Islamic Republic of); Taghinejad-Roudbaneh, M. [Department of Animal Science, Faculty of Agriculture, Tabriz Branch, Islamic Azad University, P.O. Box 51589, Tabriz (Iran, Islamic Republic of)

    2011-12-15

    This study was completed to determine effects of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on anti-nutritional factors, ruminal degradation and in vitro crude protein (CP) digestibility of whole cottonseed (WCS), soybean (SB) and canola seeds (CS). EB-irradiation eliminated completely (P<0.001) phytic acid of WCS, SB and CS at a dose of 30 kGy. EB-irradiation decreased linearly (P<0.001) the total glucosinolate content of CS. Trypsin inhibitor activity of 15, 30 and 45 kGy EB-irradiated SB was decreased by 19, 73 and 88%, respectively. Free gossypol content of WCS was reduced linearly (P<0.001) by irradiation. EB-irradiation increased linearly (P<0.001) CP digestibility of feeds. In conclusion, EB-irradiation was an effective processing method for improving the nutritive value of WCS, SB and CS. - Highlights: > Effects of electron beam (EB) irradiation on nutritive value of some oilseeds were evaluated. > EB-irradiation eliminated completely phytic acid of seeds at a dose of 30 kGy. > EB-irradiation decreased trypsin inhibitor activity of soybean. > Free gossypol content of whole cottonseed was reduced linearly by EB-irradiation. > EB-irradiation increased escape protein and crude protein digestibility of seeds.

  9. Elevated expression of proto-oncogenes accompany enhanced induction of heat-shock genes after exposure of rat embryos in utero to ionizing irradiation

    International Nuclear Information System (INIS)

    Higo, H.; Lee, J.Y.; Satow, Y.; Higo, K.

    1989-01-01

    We have recently found that the effects of exposing rat embryos in utero to teratogens capable of producing cardiac anomalies were expressed later as enhanced induction of heat-shock proteins (hsp70 family) when embryonic hearts were cultured in vitro. However, it remained to be determined whether heat-shock proteins are induced in vivo after exposure to teratogens. The heat-shock response in some mammalian systems is known to be accompanied by elevated expression of proto-oncogenes. Using gene-specific DNA probes, we examined the levels of the expression (transcription) of heat-shock protein genes and two nuclear proto-oncogenes, c-fos and c-myc, in the embryos removed from irradiated pregnant mother rats 4 or 5 days after the irradiation. We found that the levels of expression in vivo of the hsp70 and c-myc genes in the irradiated embryos increased by approximately twofold as compared with those in the control. The expression in vivo of the c-fos gene was not detected in either the irradiated or non-irradiated embryos. After 0.5-hr incubation in vitro of the embryos, however, the expression of the c-fos gene in the irradiated embryos was highly enhanced whereas the control showed no changes. Although the exact functions of these gene products still remain obscure, the enhanced expression of hsp70 gene(s) and the nuclear proto-oncogenes observed in the present study may reflect repair of intracellular damages and/or regeneration of tissue by compensatory cell proliferation, processes that may disturb the normal program of organogenesis

  10. Analysis of influence factors on the volume of pelvic bowel irradiated for rectal cancer

    International Nuclear Information System (INIS)

    He Yuxiang; Cai Yong; Zhu Xianggao; Han Shukui; Xu Bo

    2007-01-01

    Objective: To evaluate influence of prone/ supine position, gender, operation, bladder distension on bowel irradiated for patients with rectal cancer during pelvic radiotherapy. Methods: 36 patients with rectal cancer were investigated. Treatment plans were created with three dimensional treatment planning system. The dose and volume of bowel irradiated were analyzed according to dose-volume histograms (DVH) for every patient. The prescribed dose was 50 Gy. Results: The extent of bladder distension significantly influenced the mean doses and the V 45 high dose volumes of bowel irradiated. The treatment position and gender significantly influenced the V 15 low dose volume of bowel irradiated, the operation significantly influenced the mean doses of bowel. Either prone and supine position, or preoperative and postoperative, the doses of bowel irradiated for good bladder distension were lower and the volumes were smaller than that for bad bladder distension. The V 45 high dose volume of bowel irradiated for bad and good bladder distension at prone position were 15.3% and 7.4% (P=0.023), respectively, and at postoperative 14.1% and 7.2% (P=0.014), respectively. Conclusions: The doses and volumes of pelvic bowel irradiated were significantly influenced by the extent of bladder distension, and partly influenced by the prone/supine position, gender and operation. (authors)

  11. Factors influencing adherence with therapeutic sunlight exposure in older people in intermediate care facilities.

    Science.gov (United States)

    Durvasula, Seeta; Sambrook, Philip N; Cameron, Ian D

    2012-01-01

    The purpose of this study was to investigate the factors influencing low adherence with therapeutic sunlight exposure in a randomized controlled trial conducted with older people living in intermediate care facilities. The study involved participants in the FREEDOM (Falls Risk Epidemiology: Effect of vitamin D on skeletal Outcomes and other Measures) study, a randomized controlled trial of therapeutic sun exposure to reduce falls in older people in intermediate care facilities. Semi-structured interviews were conducted with thirty participants in the FREEDOM trial, and with ten sunlight officers who were employed to facilitate the sun exposure. Two focus groups involving 10 participants in the FREEDOM trial were also held at the end of the intervention period. Common themes were derived from the interview and focus group transcripts. The study showed that the perceived health benefits did not influence adherence with the sun exposure. Factors such as socializing with others and being outdoors were more important in encouraging attendance. The main barriers to adherence included the perceived inflexibility and regimentation of daily attendance, clash with other activities, unsuitable timing and heat discomfort. This study showed that providing greater flexibility and autonomy to older people in how and when they receive sun exposure is likely to improve adherence. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  12. Comments on the exposure distance as a factor of severity of A-bomb cataracts

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, S [Sugimoto Ophthalmological Clinic, Hiroshima (Japan)

    1976-09-01

    In the study of A-bomb disorders, it is important in decision of exposure dose to consider not only exposure distance from the hypocenter but also shelter factors, and 8 cases were reported as examples. Group 1 (4 cases) was exposed to A-bomb in the train 750 m east of the hypocenter, and group 2 (4 cases) was exposed in the concrete steel building 620 m east of the hypocenter. Age, exposure distance, exposure place, shelter condition, wounds, acute symptoms due to A-bomb exposure, radiation dose, condition of turbidity of the crystalline lens, effect of A-bomb on visual acuity of eight cases were listed in table. Group 1 was exposed to A-bomb at the place 130 m from the place where group 2 was exposed, but the exposed dose of group 1 was equivalent to twice that of group 2. Acute symptoms due to A-bomb exposure, turbidity of the crystalline lens, and effect of A-bomb on visual acuity were by far stronger in group 1 than in group 2. It was stressed that physical history and treatment course of the patients with A-bomb cataract were enough to be important materials on the study of A-bomb disorders.

  13. Dose- and time-dependent gene expression alterations in prostate and colon cancer cells after in vitro exposure to carbon ion and X-irradiation

    Science.gov (United States)

    Suetens, Annelies; Moreels, Marjan; Quintens, Roel; Soors, Els; Buset, Jasmine; Chiriotti, Sabina; Tabury, Kevin; Gregoire, Vincent; Baatout, Sarah

    2015-01-01

    Hadrontherapy is an advanced form of radiotherapy that uses beams of charged particles (such as protons and carbon ions). Compared with conventional radiotherapy, the main advantages of carbon ion therapy are the precise absorbed dose localization, along with an increased relative biological effectiveness (RBE). This high ballistic accuracy of particle beams deposits the maximal dose to the tumor, while damage to the surrounding healthy tissue is limited. Currently, hadrontherapy is being used for the treatment of specific types of cancer. Previous in vitro studies have shown that, under certain circumstances, exposure to charged particles may inhibit cell motility and migration. In the present study, we investigated the expression of four motility-related genes in prostate (PC3) and colon (Caco-2) cancer cell lines after exposure to different radiation types. Cells were irradiated with various absorbed doses (0, 0.5 and 2 Gy) of accelerated 13C-ions at the GANIL facility (Caen, France) or with X-rays. Clonogenic assays were performed to determine the RBE. RT-qPCR analysis showed dose- and time-dependent changes in the expression of CCDC88A, FN1, MYH9 and ROCK1 in both cell lines. However, whereas in PC3 cells the response to carbon ion irradiation was enhanced compared with X-irradiation, the effect was the opposite in Caco-2 cells, indicating cell-type–specific responses to the different radiation types. PMID:25190155

  14. Influence of the irradiation by the γ rays on various factors of immunity

    International Nuclear Information System (INIS)

    Gaude, G.; Coursaget, J.

    1955-01-01

    Exposed animals often present, in the days or weeks following the irradiation, heavy infectious lesions. The goal of this survey was to search the influence of the total irradiation by the gamma radiation from cobalt-60, on the organism, on the phagocytic power of the leukocytes and on the biogenesis of antibodies. The experiences were done on hundred animals, rabbits and guinea pigs. All irradiations have been achieved with eight sources of Cobalt 60 of 10 curies each, disposed on a sphere of 1 m, the animal living the region neighboring of the center. The intensity of the radiation, in these conditions, is about 100 roentgens per hour. (authors) [fr

  15. Early reoxygenation in tumors after irradiation: Determining factors and consequences for radiotherapy regimens using daily multiple fractions

    International Nuclear Information System (INIS)

    Crokart, Nathalie; Jordan, Benedicte F.; Baudelet, Christine; Ansiaux, Reginald; Sonveaux, Pierre; Gregoire, Vincent; Beghein, Nelson; Wever, Julie de; Bouzin, Caroline; Feron, Olivier; Gallez, Bernard

    2005-01-01

    Purpose: To characterize changes in the tumor microenvironment early after irradiation and determine the factors responsible for early reoxygenation. Methods and Materials: Fibrosarcoma type II (FSaII) and hepatocarcinoma transplantable liver tumor tumor oxygenation were determined using electron paramagnetic resonance oximetry and a fiberoptic device. Perfusion was assessed by laser Doppler, dynamic contrast-enhanced MRI, and dye penetration. Oxygen consumption was determined by electron paramagnetic resonance. The interstitial fluid pressure was evaluated by the wick-in-needle technique. Results: An increase in oxygen partial pressure was observed 3-4 h after irradiation. This increase resulted from a decrease in global oxygen consumption and an increase in oxygen delivery. The increase in oxygen delivery was due to radiation-induced acute inflammation (that was partially inhibited by the antiinflammatory agent diclofenac) and to a decrease in interstitial fluid pressure. The endothelial nitric oxide synthase pathway, identified as a contributing factor at 24 h after irradiation, did not play a role in the early stage after irradiation. We also observed that splitting a treatment of 18 Gy into two fractions separated by 4 h (time of maximal reoxygenation) had a greater effect on tumor regrowth delay than when applied as a single dose. Conclusion: Although the cell cycle redistribution effect is important for treatment protocols using multiple daily radiation fractions, the results of this work emphasize that the oxygen effect must be also considered to optimize the treatment strategy

  16. A Preliminary Study of the Application of a Model Animal-Caenorhabidity elegans' Exposure to a Low-Energy Ion Irradiation System

    International Nuclear Information System (INIS)

    Liu Xuelan; Cai Kezhou; Feng Huiyun; Xu An; Yuan Hang; Yu Zengliang

    2007-01-01

    Because of the lack of suitable animal models adapted to high vacuum stress in the low-energy ion implantation system, the bio-effects ion irradiation with an energy less than 50 keV on multi-cellular animal individuals have never been investigated so far. The nematode Caenorhabditis elegans has proved to be an excellent animal model used for the study of a broad spectrum of biological issues. The purpose of this work was to investigate the viability of this animal under ion irradiation. We studied the protection effects of glycerol and trehalose on the enhancement of nematodes' ability to bear the vacuum stress. The results showed that the survival of the nematodes was enhanced remarkably under long and slow desiccation, even without glycerol and trehalose. 15% glycerol showed a better anti-vacuum stress effect on the nematodes than trehalose did under short-time desiccation. Low-temperature pre-treatment or post-treatment of the samples had no obvious effect on the survival scored after argon ion irradiation. Moreover, little effect was induced by 15% glycerol- and vacuum-exposure on germ cell apoptosis, compared to the untreated control sample. It issuggested that such treatment would provide relatively low background for genotoxic evaluations with ion irradiation

  17. Mechanisms associated with the expression of cisplatin resistance in a human ovarian tumor cell line following exposure to fractionated x-irradiation in vitro

    International Nuclear Information System (INIS)

    Dempke, W.C.M.; Shellard, S.A.; Hosking, L.K.; Hill, B.T.

    1992-01-01

    Interactions between cisplatin (CDDP) and irradiation are of potential significance for the combined modality treatment of cancer. To identify parameters associated with CDDP resistance, the human ovarian carcinoma cell line SK-OV-3/P was pre-exposed to fractionated X-irradiation in vitro. The resultant subline (SK-OV-3/DXR-10) proved 2-fold resistant to CDDP, but not to acute X-irradiation. Consistent with unaltered dihydrofolate reductase and thymidylate synthase activities, SK-OV-3/DXR-10 cells were neither cross-resistant to methotrexate nor to 5-fluorouracil. Verapamil significantly enhanced CDDP-induced cytotoxicity in the resistant DXR-10 subline, but not in the parental cells. Resistance in the SK-OV-3/DXR-10 cells was associated with significantly decreased cisplatin uptake. After an 18 h post-treatment incubation the parental cell line appeared proficient in the removal of the intrastrand adduct Pt-AG, but deficient in removing the major adduct Pt-GG and the difunctional Pt-(GMP) 2 lesion, whilst the DXR-10 resistant subline appeared proficient in removal of all four Pt-DNA adducts. DNA polymerases α and β activities, however, were comparable in both cell lines. These data implicate both enhanced repair and increased tolerance of DNA damage as mechanisms of resistance to CDDP resulting from in vitro exposure of a human ovarian carcinoma cell line to fractionated X-irradiation. (author)

  18. Within and between Individual Variability of Exposure to Work-Related Musculoskeletal Disorder Risk Factors

    Directory of Open Access Journals (Sweden)

    Mohsen Zare

    2018-05-01

    Full Text Available Industrial companies indicate a tendency to eliminate variations in operator strategies, particularly following implementation of the lean principle. Companies believe when the operators perform the same prescribed tasks, they have to execute them in the same manner (completing the same gestures and being exposed to the same risk factors. They attempt to achieve better product quality by standardizing and reducing operational leeway. However, operators adjust and modify ways of performing tasks to balance between their abilities and the requirements of the job. This study aims to investigate the variability of exposure to physical risk factors within and between operators when executing the same prescribed tasks. The Ergonomic Standard method was used to evaluate two workstations. Seven operators were observed thirty times between repeated cycle times at those workstations. The results revealed the variability of exposure to risk factors between and within operators in the repeated execution of the same tasks. Individual characteristics and operators’ strategies might generate the variability of exposure to risk factors that may be an opportunity to reduce the risks of work-related musculoskeletal disorders (WR-MSDs. However, sometimes operators’ strategies may cause overexposure to risk factors; operators most often adopt such strategies to undertake their tasks while reducing the workload.

  19. Intensity Modulated Proton Therapy for Craniospinal Irradiation: Organ-at-Risk Exposure and a Low-Gradient Junctioning Technique

    International Nuclear Information System (INIS)

    Stoker, Joshua B.; Grant, Jonathan; Zhu, X. Ronald; Pidikiti, Rajesh; Mahajan, Anita; Grosshans, David R.

    2014-01-01

    Purpose: To compare field junction robustness and sparing of organs at risk (OARs) during craniospinal irradiation (CSI) using intensity modulated proton therapy (IMPT) to conventional passively scattered proton therapy (PSPT). Methods and Materials: Ten patients, 5 adult and 5 pediatric patients, previously treated with PSPT-based CSI were selected for comparison. Anterior oblique cranial fields, using a superior couch rotation, and posterior spinal fields were used for IMPT planning. To facilitate low-gradient field junctioning along the spine, the inverse-planning IMPT technique was divided into 3 stages. Dose indices describing target coverage and normal tissue dose, in silico error modeling, and film dosimetry were used to assess plan quality. Results: Field junction robustness along the spine was improved using the staged IMPT planning technique, reducing the worst case impact of a 4-mm setup error from 25% in PSPT to <5% of prescription dose. This was verified by film dosimetry for clinical delivery. Exclusive of thyroid dose in adult patients, IMPT plans demonstrated sparing of organs at risk as good or better than PSPT. Coverage of the cribriform plate for pediatric (V95% [percentage of volume of the target receiving at least 95% of the prescribed dose]; 87 ± 11 vs 92 ± 7) and adult (V95%; 94 ± 7 vs 100 ± 1) patients and the clinical target in pediatric (V95%; 98 ± 2 vs 100 ± 1) and adult (V95%; 100 ± 1 vs 100 ± 1) patients for PSPT and IMPT plans, respectively, were comparable or improved. For adult patients, IMPT target dose inhomogeneity was increased, as determined by heterogeneity index (HI) and inhomogeneity coefficient (IC). IMPT lowered maximum spinal cord dose, improved spinal dose homogeneity, and reduced exposure to other OARs. Conclusions: IMPT has the potential to improve CSI plan quality and the homogeneity of intrafractional dose at match lines. The IMPT approach developed may also simplify treatments and reduce

  20. Factors associated with secondhand smoke exposure in different settings: Results from the German Health Update (GEDA) 2012.

    Science.gov (United States)

    Fischer, Florian; Kraemer, Alexander

    2016-04-14

    The ubiquity of secondhand smoke (SHS) exposure at home or in private establishments, workplaces and public areas poses several challenges for the reduction of SHS exposure. This study aimed to describe the prevalence of SHS exposure in Germany and key factors associated with exposure. Results were also differentiated by place of exposure. A secondary data analysis based on the public use file of the German Health Update 2012 was conducted (n = 13,933). Only non-smokers were included in the analysis. In a multivariable logistic regression model the factors associated with SHS exposure were calculated. In addition, a further set of multivariable logistic regressions were calculated for factors associated with the place of SHS exposure (workplace, at home, bars/discotheques, restaurants, at the house of a friend). More than a quarter of non-smoking study participants were exposed to SHS. The main area of exposure was the workplace (40.9 %). The multivariable logistic regression indicated young age as the most important factor associated with SHS exposure. The odds for SHS exposure was higher in men than in women. The likelihood of SHS exposure decreased with higher education. SHS exposure and the associated factors varied between different places of exposure. Despite several actions to protect non-smokers which were implemented in Germany during the past years, SHS exposure still remains a relevant risk factor at a population level. According to the results of this study, particularly the workplace and other public places such as bars and discotheques have to be taken into account for the development of strategies to reduce SHS exposure.

  1. Is exposure to cyanobacteria an environmental risk factor for amyotrophic lateral sclerosis and other neurodegenerative diseases?

    Science.gov (United States)

    Bradley, Walter G.; Borenstein, Amy R.; Nelson, Lorene M.; Codd, Geoffrey A.; Rosen, Barry H.; Stommel, Elijah W.; Cox, Paul Alan

    2013-01-01

    There is a broad scientific consensus that amyotrophic lateral sclerosis (ALS) is caused by gene-environment interactions. Mutations in genes underlying familial ALS (fALS) have been discovered in only 5–10% of the total population of ALS patients. Relatively little attention has been paid to environmental and lifestyle factors that may trigger the cascade of motor neuron death leading to the syndrome of ALS, although exposure to chemicals including lead and pesticides, and to agricultural environments, smoking, certain sports, and trauma have all been identified with an increased risk of ALS. There is a need for research to quantify the relative roles of each of the identified risk factors for ALS. Recent evidence has strengthened the theory that chronic environmental exposure to the neurotoxic amino acid β-N-methylamino-L-alanine (BMAA) produced by cyanobacteria may be an environmental risk factor for ALS. Here we describe methods that may be used to assess exposure to cyanobacteria, and hence potentially to BMAA, namely an epidemiologic questionnaire and direct and indirect methods for estimating the cyanobacterial load in ecosystems. Rigorous epidemiologic studies could determine the risks associated with exposure to cyanobacteria, and if combined with genetic analysis of ALS cases and controls could reveal etiologically important gene-environment interactions in genetically vulnerable individuals.

  2. Environmental exposure of pregnant women to tobacco smoke and selected socio-economic factors

    Directory of Open Access Journals (Sweden)

    Paweł Kalinowski

    2017-08-01

    Conclusions. Study results indicate the problem of exposure of pregnant women to smoke. Studied socio-economic factors affect the degree of exposure to environmental tobacco smoke. There is a need to implement systematic activities in the field of social education about the influence of tobacco smoke on intrauterine development of the fetus. For this purpose it would be useful to develop a health program for women of child-bearing age with focus on the most vulnerable social groups of women. It is also necessary to provide people actively smoking from pregnant women, in particular of home environment, with health education.

  3. Socioeconomic and personal behavioral factors affecting children's exposure to VOCs in urban areas in Korea.

    Science.gov (United States)

    Byun, Hyaejeong; Ryu, Kyongnam; Jang, Kyungjo; Bae, Hyunjoo; Kim, Dongjin; Shin, Hosung; Chu, Jangmin; Yoon, Chungsik

    2010-02-01

    Volatile organic compounds (VOCs) are known to cause adverse health effects. We investigated the relationships between children's VOC exposure and socioeconomic and human activity factors with passive personal samplers, questionnaires, and time-activity diaries (TAD). Statistical analyses were conducted using SAS 9.1, and the results were organized using SigmaPlot 8.0 software. Chemicals such as benzene, toluene, 2-butanone, ethylbenzene, xylene, chloroform, n-hexane, heptane, and some kinds of decanes, which are known to adversely affect public health, were identified in measured samples. These were mainly emitted from outdoor sources (e.g., vehicular traffic) or indoor sources (e.g., household activities such as cooking and cleaning) or both. We concluded that region was the most important socioeconomic factor affecting children's VOC exposure, and the significant compounds were n-hexane (p = 0.006), 1,1,1-trichloroethane (p = 0.001), benzene (p = 0.003), toluene (p = 0.002), ethylbenzene (p = 0.020), m-, p-xylene (p = 0.014), dodecane (p = 0.003), and hexadecane (p = 0.001). Parental education, year of home construction and type of housing were also slightly correlated with personal VOC exposure. Only the concentration of o-xylene (p = 0.027) was significantly affected by the parental education, and the concentrations of benzene (p = 0.030) and 2-butanone (p = 0.049) by the type of housing. Also, tridecane (p = 0.049) and n-hexane (p = 0.033) were significantly associated with the year of home construction. When household activities such as cooking were performed indoors, children's VOC concentrations tended to be higher, especially for n-hexane, chloroform, heptane, toluene (p factors simultaneously, socioeconomic factors such as region had a greater effect on children's VOC exposures than indoor activities. From this study, we can suggest that socioeconomic factors as well as environmental factors should be considered when formulating environmental policy to

  4. Seasonal correction factors in radon exposure assessment: are they help or hindrance?

    International Nuclear Information System (INIS)

    Denman, A.R.; Groves-Kirkby, C.J.; Phillips, P.S.; Woolridge, A.C.; Crockett, R.G.M.

    2008-01-01

    Northern Hemisphere radon levels are generally higher in Winter than in Summer, primarily due to the increased interior/exterior temperature difference during the heating season, which results in greater atmospheric pressure differential and enhanced radon ingress. Following a survey of domestic radon levels in the United Kingdom (UK), the former National Radiological Protection Board (NRPB) established measurement protocols and promulgated nationally-applicable Seasonal Correction Factors (SCF). These factors convert a one-month or three-month radon concentration measurement, commencing in any month of the year, to an annual mean radon concentration. Subsequent study suggests that this approach may not be sufficiently sensitive to local conditions, and a major independent investigation reported seasonal correction factors specific to nine geographic regions, together with a composite set applicable to all regions. Similar geographical variability has been observed in other countries. In a recent evaluation of the applicability of short-term exposures in quantifying long-term domestic radon levels, radon levels in 34 houses were monitored over a 12-month period with 1-week, 1-month and 3-month exposures. Radon concentration variation departed significantly from that expected on the basis of the recommended SCFs, with year-end discontinuities at all exposure durations. Weekly monitoring with electrets was continued in three of these locations for four years. Short-term variations in radon levels were observed, particularly during the shorter exposures, and this dataset has also shown year-on-year variations. Overall, SCFs derived from this dataset are significantly lower than those recommended, but are comparable with other results from the UK and elsewhere, particularly those that recognise geological diversity and are consequently prepared on a regional rather than a national basis. These findings call into question the validity of using nationally

  5. Geographic variation in risk factors for SFG rickettsial and leptospiral exposure in Colombia.

    Science.gov (United States)

    Padmanabha, Harish; Hidalgo, Marylin; Valbuena, Gustavo; Castaneda, Elizabeth; Galeano, Armando; Puerta, Henry; Cantillo, Cesar; Mantilla, Gilma

    2009-10-01

    In order to characterize the patterns of human exposure to spotted fever group (SFG) rickettsial and leptospiral infection, IgG surveys were conducted on 642 residents of ten different areas of the rural district of Necoclí, Colombia. Areas were selected based on forest cover and human settlement pattern, and individual risk factors were elucidated through multivariate logistic models, controlling for variance clustering within communities. Overall, prevalence of high antibody titers indicating previous exposure to SFG rickettsia and leptospira was 29.2% and 35.6%, respectively, and both were most prevalent in the same peri-urban neighborhood. Forest cover .10% demonstrated the strongest independent association with leptospiral exposure, followed by homes with outdoor storage sheds. Isolated rural housing was the only variable independently associated with SFG rickettsia exposure. Community-level variables significantly modified the effects of individual risk factors. For both pathogens the eldest quartile was less exposed in periurban areas although there was no age effect overall for either. Females living in population settlements were more exposed to SFG rickettsiae but there was no sex association in isolated rural houses. Similarly, in sites with forest cover .10%, individuals working at home had higher leptospira seroprevalence, but place of work was not a risk factor in areas of forest cover ,10%. These data suggest that the patterns of maintenance and/or exposure to leptospira and rickettsia vary across different human created landscapes and settlement patterns. While contrasting risk factors may reflect the unique transmission cycles of each pathogen, the observed patterns of geographic variation suggest that both diseases may respond similarly larger scale human-ecological dynamics.

  6. Risk factors related to interfractional variation in whole pelvic irradiation for locally advanced pelvic malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, W.S.; Yang, D.S.; Lee, J.A.; Lee, S.; Park, Y.J.; Kim, C.Y. [Korea Univ. Medical Center, Seoul (Korea, Republic of). Dept. of Radiation Oncology

    2012-05-15

    Purpose: The goal of the present study was to demonstrate risk factors affecting the interfractional variation in whole pelvic irradiation. Patients and methods: Daily image acquisitions of 101 patients with locally advanced pelvic malignancy were undertaken using a kilo-voltage orthogonal on-board imager. The baseline deviation (the shift between the initial treatment and each fraction; Value{sub Base}) and day-to-day variation (the shift between the previous treatment and each fraction; Value{sub DD}) were measured. The standard deviations (SD) along the x- (right-left), y- (cranial-caudal), and z- (anterior-posterior) axes (SD[x], SD[y], and SD[z], respectively), the 3D vector of the SD (SD[3D]), and the mean of 3D shift (mean[3D]) were calculated in each patient. Various clinical factors, lumbar pelvic balance and rotation, and the shift of 5 consecutive fractions from the initial treatment (Value{sub 5Fx}) were investigated as risk factors. Results: The prone set-up showed a larger mean{sub Base}[3D] than in the supine position (p =0.063). A body mass index (BMI) {>=} 30 kg/m{sup 2} resulted in the largest mean{sub DD}[3D] (p = 0.078) and SD{sub DD}[3D] (p = 0.058). All the SD{sub 5Fx} along the x-, y-, and z-axes had moderate linear relationships with SD{sub Base} and SD{sub DD} (p < 0.001). The SD{sub 5Fx}[3D] also had a moderate linear relationship with the mean{sub Base}[3D], mean{sub DD}[3D], SD{sub Base}[3D], and SD{sub DD}[3D] (p < 0.001). In multivariate analysis, the SD{sub 5Fx} had the same significant relationship with SD{sub Base} and SD{sub DD} (p < 0.001). A BMI {>=} 30 kg/m{sup 2} was associated with the largest SD{sub DD}[x] (p = 0.003). Conclusion: Close surveillance through high-quality and frequent image guidance is recommended for patients with extensive variations of the initial five consecutive fractions or obesity. (orig.)

  7. A National Study on Nurses' Exposure to Occupational Violence in Lebanon: Prevalence, Consequences and Associated Factors.

    Directory of Open Access Journals (Sweden)

    Mohamad Alameddine

    Full Text Available Healthcare institutions have commonly reported exposure of employees, particularly nurses, to high levels of occupational violence. Despite such evidence in the Middle East Region, there is a dearth of national studies that have systematically investigated this phenomenon. This study investigates the prevalence, characteristics, consequences and factors associated with nurses' exposure to occupational violence in Lebanon.A cross-sectional design was utilized to survey a nationally representative sample of 915 nurses registered with the Order of Nurses in Lebanon. Stratified random sampling by governorate was utilized. Individually-mailed questionnaires collected information on exposure to violence, degree of burnout and demographic/professional background. The main outcome variables were exposure to verbal abuse (never, 1-3, 4-9 and 10+ times and physical violence (never, ever over the past 12-months. Descriptive statistics were used to estimate prevalence of violence. Multivariable, binomial and multinomial regression models were carried out to investigate the correlates of exposure to verbal abuse and physical violence, respectively.Response rate was 64.8%. Over the last year, prevalence of nurses' exposure to verbal abuse was 62%, (CI: 58-65% and physical violence was 10%, (CI: 8-13%. Among respondents, 31.7% of nurses indicated likelihood to quit their jobs and 22.3% were undetermined. Furthermore, 54.1% reported high levels of emotional exhaustion and 28.8% reported high levels of depersonalization. Compared to nurses with no exposure to verbal abuse, nurses reporting high exposure had high levels of emotional exhaustion (OR:6.4; CI:1.76-23.32, depersonalization (OR:6.8; CI: 3-15 and intention to quit job (OR:3.9; CI: 1.8-8.3. They further reported absence of anti-violence policies at their institutions (OR: 3; CI: 1.5-6.3. Nurses that were ever exposed to physical violence were more likely to be males (OR: 2.2; CI: 1.1-4.3, working day and

  8. Further Identification of the Effect of Bradykinin Potentiating Factor Isolated From Scorpion Venom on Irradiated White Rat

    International Nuclear Information System (INIS)

    Hasan, H.F.

    2011-01-01

    Scorpion venom of Androctonus amoreuxi contains a strong bradykinin potentiating factor (BPF) that augments bradykinin effect through enhancing its release and acts as an angiotensin converting enzyme inhibitor (ACEI). Both irradiation and stimulation of renin-angiotensin system (RAS) induce oxidative stress. Possible interruption of the RAS with an ACEI induced by BPF isolated from the scorpion, Androctonus amoreuxi venom or the presence of angiotensin II receptor blocker (ARB) losartan and/or γ- radiation were evaluated. The examined parameters included blood erythrocytes count (RBC), total leucocytic count (WBC), haemoglobin content (Hb) and hematocrit value (Hct) as well as, glutathione content (GSH), malondialdehyde (MDA) and advanced oxidative protein product (AOPP) of kidney homogenate besides aldosterone, sodium, potassium, chloride, calcium, urea, creatinine and uric acid levels of serum. A group of rats (70 - 80 gm each) were received i.p. injection of BPIF (1μg / g body wt) twice per week for three weeks, while the other group received i.p. injection of losartan (5μg / g body wt) twice per week for three weeks. γ-Irradiation was performed at a dose level of 4Gy. All animals were examined after an investigation period of 21 days from γ- irradiation. Either BPF or losartan was performed together with irradiation. The results pointed out that irradiation discerned a significant elevation in the level of MDA, AOPP, aldosterone, sodium, urea and creatinine, and a significant drop in the haematological values (RBCs, WBCs, Hb and Hct), GSH, calcium and uric acid. Repeated injections of BPF or losartan had a beneficial result against the deleterious effect of γ- irradiation. The present investigation clarifies comparable effects for treatment of radiation damage to the kidney through RAS by BPF as (ACEI) and losartan as (ARB). The present work adds further identification to the properties of BPF in controlling of radiation damage. Therapeutic agents from

  9. The effects of irradiance and exposure time on the surface roughness of bulk-fill composite resin restorative materials

    Science.gov (United States)

    Alkhudhairy, Fahad I.

    2018-01-01

    Objectives: To evaluate the surface roughness of 4 different bulk-fill resin-based composites cured using different irradiance levels. Methods: This in vitro study was performed in February 2017 to August 2017 at the College of Dentistry, King Saud University. Twenty-four specimens were prepared from each of the bulk-fill materials [Tetric N-Ceram (TNC), SonicFill (SF), Smart Dentin Replacement (SDR), and Filtek Bulk-Fill (FB)] using a brass metal mold, resulting in a total of 96 specimens, cured using a Bluephase N light curing unit. Half of the total number of specimens (N=48) were cured using high-power irradiance (1200 mW/cm2) for 20 seconds, while the remaining half (N=48) were cured using low power irradiance (650 mW/cm2) for 40 seconds. After 24 hours, baseline surface roughness of each specimen was analyzed using a profilometer, then polished using Sof-lex abrasive disks, and the surface roughness of all groups was assessed. Results: Post-polished SonicFill cured at high irradiance had the highest mean surface roughness (0.23±0.03), whereas pre-polished Smart Dentin Replacement (0.11±0.01) and SonicFill (0.11±0.02) cured at low irradiance had the lowest mean surface roughness. Conclusion: High curing irradiance (1,200 mW/cm2) had no positive influence on the surface roughness of Filtek Bulk Fill and Tetric N-Ceram bulk-fill RBCs compared with lower curing irradiance (650 mW/cm2). However, the difference of curing irradiance significantly affected the surface roughness in SDR and sonic fill RBCs. PMID:29436570

  10. Biological study on the effect of an anabolic steroidal agent administration pre-exposure to whole body gamma irradiated male mice

    International Nuclear Information System (INIS)

    Aly, S.M.; Eldawy, H.A.E.; Ragab, E.A.

    2002-01-01

    The present study was prepared to evaluate the potency of methoxy dimethylamino phenyl epiandrosterone (an anabolic agent animal in origin with an additive side chain) in a dose of 35 μ/g/kg b.wt in male albino mice as a radio-protective agent pre-exposure to gamma irradiation. This was accomplished through measuring follicular stimulating hormone (FSH), luteinizing hormone (LH) and prostaglandin-E 2 (PGE 2 ) and endothelin in plasma of mice. Meanwhile, observations of the chromosomal aberrations and sperm head abnormalities were recorded. The administration of the anabolic agent pre-irradiation resulted in slightly non-significant amelioration in the pituitary hormone levels and in levels of PGE 2 and endothelin

  11. Reduction in flatulence factors in mung beans (Vigna radiata) using low-dose gamma-irradiation

    International Nuclear Information System (INIS)

    Machaiah, J.P.; Pednekar, M.D.; Thomas, P.

    1999-01-01

    Mungbeans (Vigna radiata), control and gamma-irradiated at insect disinfestation dose levels (0.25 and 0.75 kGy) were germinated (0-6 Bays) and the qualitative and quantitative changes in soluble carbohydrates were studied in detail. The key flatulence-producing raffinose family oligosaccharides inmungbeans were degraded in the irradiated samples at the onset of the germination (0-2 days) compared to the control where it occurred much later (>4days). However, the reducing sugars, mainly glucose, fructose and galactose, which are metabolised easily, were enhanced in the irradiated samples. At low dose (0.25 kGy), irradiation had no effect on germination and sprout length, indicating that irradiated beans are suitable for use as sprouted beans. These observations clearly indicate that gamma-irradiation at insect disinfestation dose levels improved the digestibility and nutritional quality of mung beans by reducing the content of oligosaccharides responsible for intestinal gas production. (C) 1999 Society of Chemical Industry

  12. Music exposure differentially alters the levels of brain-derived neurotrophic factor and nerve growth factor in the mouse hypothalamus.

    Science.gov (United States)

    Angelucci, Francesco; Ricci, Enzo; Padua, Luca; Sabino, Andrea; Tonali, Pietro Attilio

    2007-12-18

    It has been reported that music may have physiological effects on blood pressure, cardiac heartbeat, respiration, and improve mood state in people affected by anxiety, depression and other psychiatric disorders. However, the physiological bases of these phenomena are not clear. Hypothalamus is a brain region involved in the regulation of body homeostasis and in the pathophysiology of anxiety and depression through the modulation of hypothalamic-pituitary-adrenal (HPA) axis. Hypothalamic functions are also influenced by the presence of the neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which are proteins involved in the growth, survival and function of neurons in the central nervous system. The aim of this study was to investigate the effect of music exposure in mice on hypothalamic levels of BDNF and NGF. We exposed young adult mice to slow rhythm music (6h per day; mild sound pressure levels, between 50 and 60 dB) for 21 consecutive days. At the end of the treatment mice were sacrificed and BDNF and NGF levels in the hypothalamus were measured by enzyme-linked immunosorbent assay (ELISA). We found that music exposure significantly enhanced BDNF levels in the hypothalamus. Furthermore, we observed that music-exposed mice had decreased NGF hypothalamic levels. Our results demonstrate that exposure to music in mice can influence neurotrophin production in the hypothalamus. Our findings also suggest that physiological effects of music might be in part mediated by modulation of neurotrophins.

  13. Toddler exposure to flame retardant chemicals: Magnitude, health concern and potential risk- or protective factors of exposure: Observational studies summarized in a systematic review.

    Science.gov (United States)

    Sugeng, Eva J; de Cock, Marijke; Schoonmade, Linda J; van de Bor, Margot

    2017-10-01

    Endocrine disrupting flame retardant (FR) chemicals form a human health concern, that is investigated mostly from the perspective of adult- and early life exposure. No overview of studies on toddler exposure and health effects exist. However, toddlerhood is a critical developmental period and toddlers are at increased risk for exposure because of their age-specific behavior. This systematic review encompasses toddler FR exposure studies in three countries, associated health effects and potential environmental, demographic, or behavioral risk- or protective factors for toddler exposure. A systematic literature search in four databases (PubMed, Embase.com, The Cochrane Library (via Wiley) and Web of Science Core collection) resulted in the identification of ten publications representing seven unique studies that measured brominated and/or phosphorylated FRs in toddlers' (8-24 month-old) serum, urine, hand wipes and feces. This review showed that toddlers are exposed to a range of FRs, that thyroid hormone disruption is associated with FR exposure and that factors in the indoor environment, including products such as plastic toys, might increase FR exposure. Considering the limited amount of studies, and the variety of biological matrices, FRs, and risk- and protective factors, this review did not reveal a uniform pattern of toddler exposure across the different cohorts studied. More evidence is necessary and considering the feasibility of invasive sampling in young children, we suggest to emphasize research on non-invasive matrices. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Predictive factors for percutaneous and mucocutaneous exposure among healthcare workers in a developing country

    Directory of Open Access Journals (Sweden)

    Zeynep Türe

    2016-09-01

    Full Text Available The aim of this study is to determine the risk factors for percutaneous and mucocutaneous exposures in healthcare workers (HCW in one of the largest centers of a middle income country, Turkey. This study has a retrospective design. HCWs who presented between August 2011 and June 2013, with Occupational Exposures (OEs (cases and those without (controls were included. Demographic information was collected from infection control committee documents. A questionnaire was used to ask the HCWs about their awareness of preventive measures. HCWs who work with intensive work loads such as those found in emergency departments or intensive care units have a higher risk of OEs. Having heavy workloads and hours increases the risk of percutaneous and mucocutaneous exposures. For that reason the most common occupation groups are nurses and cleaning staff who are at risk of OEs. Increasing work experience has reduced the frequency of OEs.

  15. Comparative quantification of alcohol exposure as risk factor for global burden of disease.

    Science.gov (United States)

    Rehm, Jürgen; Klotsche, Jens; Patra, Jayadeep

    2007-01-01

    Alcohol has been identified as one of the most important risk factors in the burden experienced as a result of disease. The objective of the present contribution is to establish a framework to comparatively quantify alcohol exposure as it is relevant for burden of disease. Different key indicators are combined to derive this quantification. First, adult per capita consumption, composed of recorded and unrecorded consumption, yields the best overall estimate of alcohol exposure for a country or region. Second, survey information is used to allocate the per capita consumption into sex and age groups. Third, an index for detrimental patterns of drinking is used to determine the additional impact on injury and cardiovascular burden. The methodology is applied to estimate global alcohol exposure for the year 2002. Finally, assumptions and potential problems of the approach are discussed. Copyright (c) 2007 John Wiley & Sons, Ltd.

  16. Determination of Neutron Flux Parameter f and α and k0 Factor in Irradiation Facility of RSG GA Siwabessy reactor

    International Nuclear Information System (INIS)

    Amir Hamzah

    2004-01-01

    Determination of neutron flux thermal to epithermal ratio f and parameter α and k 0 factor has been done in irradiation facility of RSG G.A. Siwabessy reactor. Those parameters are needed to determine the concentration of an element in a sample using k 0 NAA method. Parameters f was measured using foil activation method and α parameter was obtained from power function fitting at epithermal neutron spectrum. Based on the fitting method the a parameter was determined of 0.0267,0.0255 and -0.0346 at system rabbit, IP2 and CIP irradiation position. The k 0 factor is depended on absolute gamma fraction. The neutron flux thermal to epithermal ratio f at all rabbit system is closed to 40. (author)

  17. p53-independent early and late apoptosis is mediated by ceramide after exposure of tumor cells to photon or carbon ion irradiation

    International Nuclear Information System (INIS)

    Alphonse, Gersende; Maalouf, Mira; Battiston-Montagne, Priscillia; Ardail, Dominique; Beuve, Michaël; Rousson, Robert; Taucher-Scholz, Gisela; Fournier, Claudia; Rodriguez-Lafrasse, Claire

    2013-01-01

    To determine whether ceramide is responsible for the induction of p53-independent early or late apoptosis in response to high- and low-Linear-Energy-Transfer (LET) irradiation. Four cell lines displaying different radiosensitivities and p53-protein status were irradiated with photons or 33.4 or 184 keV/μm carbon ions. The kinetics of ceramide production was quantified by fluorescent microscopy or High-Performance-Liquid-Chromatogaphy and the sequence of events leading to apoptosis by flow cytometry. Regardless of the p53-status, both low and high-LET irradiation induced an early ceramide production in radiosensitive cells and late in the radioresistant. This production strongly correlated with the level of early apoptosis in radiosensitive cells and delayed apoptosis in the radioresistant ones, regardless of radiation quality, tumor type, radiosensitivity, or p53-status. Inhibition of caspase activity or ceramide production showed that, for both types of radiation, ceramide is essential for the initiation of early apoptosis in radiosensitive cells and late apoptosis following mitotic catastrophe in radioresistant cells. Ceramide is a determining factor in the onset of early and late apoptosis after low and high-LET irradiation and is the mediator of the p53-independent-apoptotic pathway. We propose that ceramide is the molecular bridge between mitotic catastrophe and the commitment phase of delayed apoptosis in response to irradiation

  18. Dose-dependent induction of transforming growth factor β (TGF-β) in the lung tissue of fibrosis-prone mice after thoracic irradiation

    International Nuclear Information System (INIS)

    Ruebe, Claudia E.; Uthe, Daniela; Schmid, Kurt W.; Richter, Klaus D.; Wessel, Jan; Schuck, Andreas; Willich, Norman; Ruebe, Christian

    2000-01-01

    Purpose: The lung is the major dose-limiting organ for radiotherapy of cancer in the thoracic region. The pathogenesis of radiation-induced lung injury at the molecular level is still unclear. Immediate cellular damage after irradiation is supposed to result in cytokine-mediated multicellular interactions with induction and progression of fibrotic tissue reactions. The purpose of this investigation was to evaluate the acute and long-term effects of radiation on the gene expression of transforming growth factor beta (TGF-β) in a model of lung injury using fibrosis-sensitive C57BL/6 mice. Methods and Materials: The thoraces of C57BL/6 mice were irradiated with 6 and 12 Gy, respectively. Treated and sham-irradiated control mice were sacrificed at times corresponding to the latent period (1, 3, 6, 12, 24, 48, 72 hours and 1 week postirradiation), the pneumonic phase (2, 4, 8, and 16 weeks postirradiation), and the beginning of the fibrotic phase (24 weeks postirradiation). The lung tissue from three different mice per dosage and time point was analyzed by a combination of polymerase chain reaction (PCR), immunohistochemistry, and light microscopy. The mRNA expression of TGF-β was quantified by competitive reverse transcriptase/polymerase chain reaction (RT-PCR); the cellular origin of the TGF-β protein was identified by immunohistochemical staining (alkaline phosphatase-anti-alkaline phosphatase [APAAP]). The cytokine expression on mRNA and protein level was correlated with the histopathological alterations. Results: Following thoracic irradiation with a single dose of 12 Gy, radiation-induced TGF-β release in lung tissue was appreciable already within the first hours (1, 3, and 6 hours postirradiation) and reached a significant increase after 12 hours; subsequently (48 hours, 72 hours, and 1 week postirradiation) the TGF-β expression declined to basal levels. At the beginning of the pneumonic phase, irradiation-mediated stimulation of TGF-β release reached

  19. Tobacco Smoke Exposure Impairs Brain Insulin/IGF Signaling: Potential Co-Factor Role in Neurodegeneration.

    Science.gov (United States)

    Deochand, Chetram; Tong, Ming; Agarwal, Amit R; Cadenas, Enrique; de la Monte, Suzanne M

    2016-01-01

    Human studies suggest tobacco smoking is a risk factor for cognitive impairment and neurodegeneration, including Alzheimer's disease (AD). However, experimental data linking tobacco smoke exposures to underlying mediators of neurodegeneration, including impairments in brain insulin and insulin-like growth factor (IGF) signaling in AD are lacking. This study tests the hypothesis that cigarette smoke (CS) exposures can impair brain insulin/IGF signaling and alter expression of AD-associated proteins. Adult male A/J mice were exposed to air for 8 weeks (A8), CS for 4 or 8 weeks (CS4, CS8), or CS8 followed by 2 weeks recovery (CS8+R). Gene expression was measured by qRT-PCR analysis and proteins were measured by multiplex bead-based or direct binding duplex ELISAs. CS exposure effects on insulin/IGF and insulin receptor substrate (IRS) proteins and phosphorylated proteins were striking compared with the mRNA. The main consequences of CS4 or CS8 exposures were to significantly reduce insulin R, IGF-1R, IRS-1, and tyrosine phosphorylated insulin R and IGF-1R proteins. Paradoxically, these effects were even greater in the CS8+R group. In addition, relative levels of S312-IRS-1, which inhibits downstream signaling, were increased in the CS4, CS8, and CS8+R groups. Correspondingly, CS and CS8+R exposures inhibited expression of proteins and phosphoproteins required for signaling through Akt, PRAS40, and/or p70S6K, increased AβPP-Aβ, and reduced ASPH protein, which is a target of insulin/IGF-1 signaling. Secondhand CS exposures caused molecular and biochemical abnormalities in brain that overlap with the findings in AD, and many of these effects were sustained or worsened despite short-term CS withdrawal.

  20. Uveal melanoma in relation to ultraviolet light exposure and host factors.

    Science.gov (United States)

    Holly, E A; Aston, D A; Char, D H; Kristiansen, J J; Ahn, D K

    1990-09-15

    We conducted a case-control interview study among 1277 subjects (407 patients, 870 controls selected by using random digit dial) in 11 western United States to determine whether uveal melanoma and cutaneous melanoma shared common risk factors. After adjustment for other factors, the risk of uveal melanoma was increased for those with green, gray, or hazel eyes [relative risk (RR) = 2.5, P less than 0.001] or blue eyes (RR = 2.2, P less than 0.001) when compared to brown. A tendency to sunburn after 0.5 h midday summer sun exposure increased risk for uveal melanoma (burn with tanning RR = 1.5, P = 0.02; burn with little tanning RR = 1.8, P less than 0.001; burn with no tanning RR = 1.7, P = 0.002); as did exposure to UV or black lights (RR = 3.7, P = 0.003); and welding burn, sunburn of the eye, or snow blindness (RR = 7.2, P less than 0.001). An association with uveal melanoma was also noted with an increasing number of large nevi (P = 0.04 for trend), although the individual risk estimates were not remarkable. These data suggest that host factors and exposure to UV light are risk factors for uveal melanoma.

  1. Exposure to occupational therapy as a factor influencing recruitment to the profession.

    Science.gov (United States)

    Byrne, Nicole

    2015-08-01

    This article provides insight into the impact that exposure to an occupational therapist, in personal capacity or via a professional interaction, has on the decision to enter an occupational therapy undergraduate programme. A quantitative survey was completed by 139 occupational therapy students. The survey tool focussed on the students' exposure to a range of allied health professions (e.g. occupational therapy, physiotherapy, psychology) and investigated how exposure to occupational therapy had influenced their decision to enter the programme. The results indicated that over 70% of respondents had personal professional exposure to occupational therapy prior to making a career decision. Exposure most frequently involved occupational therapy intervention of a friend or family member. The majority of students who had professional exposure to occupational therapy (e.g. family, self, friend received occupational therapy) identified that it was the most influential factor in their career choice. Forty per cent of the occupational therapy students did not enter the programme straight from school and the influence of 'working with an occupational therapist' was noteworthy for mature aged students. Occupational therapists need to consider that every interaction they have with the community provides valuable information regarding the profession and gives insight into occupational therapy as a potential career path for other people. Additionally, the current research identifies there were differences in the impact, type and number of exposures for different student groups, and this potentially offers some insight into ways in which occupational therapy could target specific groups within the community to increase future diversity in the profession. © 2015 Occupational Therapy Australia.

  2. Personal factors influencing agreement between expert and self-reported assessments of an occupational exposure.

    Science.gov (United States)

    Neilson, Heather K; Sass-Kortsak, Andrea; Lou, W Y Wendy; Purdham, James T

    2007-01-01

    This study aimed to identify personal factors associated with expert and respondent agreement on past occupational exposure. Epidemiologic data was collected from 1995 to 1998 in a community-based, case-control study of prostate cancer. Using longest jobs and excluding agreement on "never" exposure, self-reported and expert estimates of ever/ never exposure, by skin or ingestion, to polycyclic aromatic hydrocarbons were compared. Agreement between respondents and the expert was 53.9 percent (N=1,038), with overreporting being more common than underreporting relative to the expert (31.8 percent versus 14.4 percent). In multiple logistic regression models, white-collar occupational status was significantly associated with overreporting (odds ratio [OR] = 0.142; 95 percent confidence interval [CI]: 0.095-0.211; blue-collar versus white-collar), while age was associated with underreporting (OR=1.077; 95 percent CI: 1.043-1.112; one-year increase). Neither job satisfaction nor risk perception appeared to confound other associations. In future studies, overreporting by white-collar workers might be avoided by providing clearer definitions of exposure, whereas elderly respondents may require aids to enhance exposure recall.

  3. Heat exposure and socio-economic vulnerability as synergistic factors in heat-wave-related mortality

    International Nuclear Information System (INIS)

    Rey, Gregoire; Fouillet, Anne; Bessemoulin, Pierre; Frayssinet, Philippe; Dufour, Anne; Jougla, Eric; Hemon, Denis

    2009-01-01

    Heat waves may become a serious threat to the health and safety of people who currently live in temperate climates. It was therefore of interest to investigate whether more deprived populations are more vulnerable to heat waves. In order to address the question on a fine geographical scale, the spatial heterogeneity of the excess mortality in France associated with the European heat wave of August 2003 was analysed. A deprivation index and a heat exposure index were used jointly to describe the heterogeneity on the Canton scale (3,706 spatial units). During the heat wave period, the heat exposure index explained 68% of the extra-Poisson spatial variability of the heat wave mortality ratios. The heat exposure index was greater in the most urbanized areas. For the three upper quintiles of heat exposure in the densely populated Paris area, excess mortality rates were twofold higher in the most deprived Cantons (about 20 excess deaths/100,000 people/day) than in the least deprived Cantons (about 10 excess deaths/100,000 people/day). No such interaction was observed for the rest of France, which was less exposed to heat and less heterogeneous in terms of deprivation. Although a marked increase in mortality was associated with heat wave exposure for all degrees of deprivation, deprivation appears to be a vulnerability factor with respect to heat-wave-associated mortality.

  4. Pesticide exposure as risk factor for non-Hodgkin lymphoma including histopathological subgroup analysis.

    Science.gov (United States)

    Eriksson, Mikael; Hardell, Lennart; Carlberg, Michael; Akerman, Måns

    2008-10-01

    We report a population based case-control study of exposure to pesticides as risk factor for non-Hodgkin lymphoma (NHL). Male and female subjects aged 18-74 years living in Sweden were included during December 1, 1999, to April 30, 2002. Controls were selected from the national population registry. Exposure to different agents was assessed by questionnaire. In total 910 (91 %) cases and 1016 (92%) controls participated. Exposure to herbicides gave odds ratio (OR) 1.72, 95% confidence interval (CI) 1.18-2.51. Regarding phenoxyacetic acids highest risk was calculated for MCPA; OR 2.81, 95% CI 1.27-6.22, all these cases had a latency period >10 years. Exposure to glyphosate gave OR 2.02, 95% CI 1.10-3.71 and with >10 years latency period OR 2.26, 95% CI 1.16-4.40. Insecticides overall gave OR 1.28, 95% CI 0.96-1.72 and impregnating agents OR 1.57, 95% CI 1.07-2.30. Results are also presented for different entities of NHL. In conclusion our study confirmed an association between exposure to phenoxyacetic acids and NHL and the association with glyphosate was considerably strengthened.

  5. Radiation Exposure in Endovascular Infra-Renal Aortic Aneurysm Repair and Factors that Influence It

    Directory of Open Access Journals (Sweden)

    Rui Machado

    Full Text Available Abstract Objective: The endovascular repair of aortic abdominal aneurysms exposes the patients and surgical team to ionizing radiation with risk of direct tissue damage and induction of gene mutation. This study aims to describe our standard of radiation exposure in endovascular aortic aneurysm repair and the factors that influence it. Methods: Retrospective analysis of a prospective database of patients with abdominal infra-renal aortic aneurysms submitted to endovascular repair. This study evaluated the radiation doses (dose area product (DAP, fluoroscopy durations and their relationships to the patients, aneurysms, and stent-graft characteristics. Results: This study included 127 patients with a mean age of 73 years. The mean DAP was 4.8 mGy.m2, and the fluoroscopy time was 21.8 minutes. Aortic bilateral iliac aneurysms, higher body mass index, aneurysms with diameters larger than 60 mm, necks with diameters larger than 28 mm, common iliac arteries with diameters larger than 20 mm, and neck angulations superior to 50 degrees were associated with an increased radiation dose. The number of anatomic risk factors present was associated with increased radiation exposure and fluoroscopy time, regardless of the anatomical risk factors. Conclusion: The radiation exposure during endovascular aortic aneurysm repair is significant (mean DAP 4.8 mGy.m2 with potential hazards to the surgical team and the patients. The anatomical characteristics of the aneurysm, patient characteristics, and the procedure's technical difficulty were all related to increased radiation exposure during endovascular aortic aneurysm repair procedures. Approximately 40% of radiation exposure can be explained by body mass index, neck angulation, aneurysm diameter, neck diameter, and aneurysm type.

  6. Accelerated partial-breast irradiation with interstitial implants. Analysis of factors affecting cosmetic outcome

    International Nuclear Information System (INIS)

    Ott, Oliver J.; Lotter, Michael; Fietkau, Rainer; Strnad, Vratislav

    2009-01-01

    Purpose: To analyze patient-, disease-, and treatment-related factors for their impact on cosmetic outcome (CO) after interstitial multicatheter accelerated partial-breast irradiation (APBI). Patients and Methods: Between April 2001 and January 2005, 171 patients with early breast cancer were recruited in Erlangen for this subanalysis of the German-Austrian APBI phase II-trial. 58% (99/171) of the patients received pulsed-dose-rate (PDR), and 42% (72/171) high-dose-rate (HDR) brachytherapy. Prescribed reference dose for HDR brachytherapy was 32 Gy in eight fractions of 4 Gy, twice daily. Prescribed reference dose in PDR brachytherapy was 49.8 Gy in 83 consecutive fractions of 0.6 Gy each hour. Total treatment time was 3-4 days. Endpoint of this evaluation was the CO, graded as excellent, good, fair, or poor. Patients were divided in two groups with an excellent (n = 102) or nonexcellent (n = 69) cosmetic result. Various factors were analyzed for their impact on excellent CO. Results: The median follow-up time was 52 months (range: 21-91 months). Cosmetic results were rated as excellent in 59.6% (102/171), good in 29.8% (51/171), fair in 9.9% (17/171), and poor in 0.6% (1/171). The initial cosmetic status was significantly worse for the nonexcellent CO group (p = 0.000). The percentage of patients who received PDR brachytherapy APBI was higher in the nonexcellent CO group (68.1% vs. 51%; p = 0.026). Acute toxicity was higher in the nonexcellent CO group (24.6% vs. 12.7%; p = 0.045). Furthermore, the presence of any late toxicity was found to be associated with a worse cosmetic result (65.2% vs. 18.6%; p = 0.000). In detail, the appearance of skin hyperpigmentation (p 0.034), breast tissue fibrosis (p = 0.000), and telangiectasia (p = 0.000) had a negative impact on CO. Conclusion: The initial, surgery-associated cosmetic status, brachytherapy modality, and the presence of acute and late toxicities were found to have an impact on overall CO. Our data have proven that

  7. Development and evaluation of probability density functions for a set of human exposure factors

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, R.L.; McKone, T.E.; Bodnar, A.; Jacobson, J.

    1999-06-01

    The purpose of this report is to describe efforts carried out during 1998 and 1999 at the Lawrence Berkeley National Laboratory to assist the U.S. EPA in developing and ranking the robustness of a set of default probability distributions for exposure assessment factors. Among the current needs of the exposure-assessment community is the need to provide data for linking exposure, dose, and health information in ways that improve environmental surveillance, improve predictive models, and enhance risk assessment and risk management (NAS, 1994). The U.S. Environmental Protection Agency (EPA) Office of Emergency and Remedial Response (OERR) plays a lead role in developing national guidance and planning future activities that support the EPA Superfund Program. OERR is in the process of updating its 1989 Risk Assessment Guidance for Superfund (RAGS) as part of the EPA Superfund reform activities. Volume III of RAGS, when completed in 1999 will provide guidance for conducting probabilistic risk assessments. This revised document will contain technical information including probability density functions (PDFs) and methods used to develop and evaluate these PDFs. The PDFs provided in this EPA document are limited to those relating to exposure factors.

  8. Optimization of exposure factors for X-ray radiography non-destructive testing of pearl oyster

    Science.gov (United States)

    Susilo; Yulianti, I.; Addawiyah, A.; Setiawan, R.

    2018-03-01

    One of the processes in pearl oyster cultivation is detecting the pearl nucleus to gain information whether the pearl nucleus is still attached in the shell or vomited. The common tool used to detect pearl nucleus is an X-ray machine. However, an X-ray machine has a drawback that is the energy used is higher than that used by digital radiography. The high energy make the resulted image is difficult to be analysed. One of the advantages of digital radiography is the energy used can be adjusted so that the resulted image can be analysed easily. To obtain a high quality of pearl image using digital radiography, the exposure factors should be optimized. In this work, optimization was done by varying the voltage, current, and exposure time. Then, the radiography images were analysed using Contrast to Noise Ratio (CNR). From the analysis, it can be determined that the optimum exposure factors are 60 kV of voltage, 16 mA of current, and 0.125 s of exposure time which result in CNR of 5.71.

  9. Development and evaluation of probability density functions for a set of human exposure factors

    International Nuclear Information System (INIS)

    Maddalena, R.L.; McKone, T.E.; Bodnar, A.; Jacobson, J.

    1999-01-01

    The purpose of this report is to describe efforts carried out during 1998 and 1999 at the Lawrence Berkeley National Laboratory to assist the U.S. EPA in developing and ranking the robustness of a set of default probability distributions for exposure assessment factors. Among the current needs of the exposure-assessment community is the need to provide data for linking exposure, dose, and health information in ways that improve environmental surveillance, improve predictive models, and enhance risk assessment and risk management (NAS, 1994). The U.S. Environmental Protection Agency (EPA) Office of Emergency and Remedial Response (OERR) plays a lead role in developing national guidance and planning future activities that support the EPA Superfund Program. OERR is in the process of updating its 1989 Risk Assessment Guidance for Superfund (RAGS) as part of the EPA Superfund reform activities. Volume III of RAGS, when completed in 1999 will provide guidance for conducting probabilistic risk assessments. This revised document will contain technical information including probability density functions (PDFs) and methods used to develop and evaluate these PDFs. The PDFs provided in this EPA document are limited to those relating to exposure factors

  10. Preliminary studies on factors controlling the rate of regrowth of heavily x-irradiated rat rhabdomyosarcoma tumors

    International Nuclear Information System (INIS)

    Tenforde, T.S.; Curtis, S.B.; Woodruff, H.K.; Parks, D.L.; Daniels, S.J.; Crabtree, K.E.; Schilling, W.A.; DeGuzman, R.J.

    1977-12-01

    Following large single doses of x rays, rat rhabdomyosarcoma tumors exhibit a volume response which characteristically has a swelling phase, a regression phase, a rapid ''initial'' regrowth phase and a slow ''late'' regrowth phase. The preliminary experiments reported here were designed to examine three mechanisms that may underlie the reduction in growth rate occurring in the late regrowth phase; heritable non-lethal cellular damage, host immunity, delayed post-irradiation tissue and vascular damage. Based on retransplantation experiments and studies with immunosuppressed rats, neither heritable non-lethal damage nor host immune factors appear to influence the regrowth rate of tumors receiving radiation doses well below the cure level. After an x-ray dose approaching the cure level, regrowing tumors were observed to have a greatly reduced growth rate, possibly reflecting the presence of heritable non-lethal damage and/or an increased antigenicity of the heavily irradiated tumor cells. Morphometric analysis of histological sections did not reveal statistically significant abnormalities at the cellular level during the late regrowth phase, except for an increase in the percentage of necrotic tissue relative to non-irradiated tumors. The morphological resolution of small blood vessels was not adequate to evaluate delayed vascular damage in regrowing irradiated tumors

  11. Prospective risk factors for adolescent PTSD: sources of differential exposure and differential vulnerability.

    Science.gov (United States)

    Milan, Stephanie; Zona, Kate; Acker, Jenna; Turcios-Cotto, Viana

    2013-02-01

    There are two types of risk factors for developing PTSD: factors that increase the likelihood of experiencing a potentially traumatizing event and factors that increase the likelihood of developing symptoms following such events. Using prospective data over a two-year period from a large, diverse sample of urban adolescents (n = 1242, Mean age = 13.5), the current study differentiates these two sources of risk for developing PTSD in response to violence exposure. Five domains of potential risk and protective factors were examined: community context (e.g., neighborhood poverty), family risk (e.g., family conflict), behavioral maladjustment (e.g., internalizing symptoms), cognitive vulnerabilities (e.g., low IQ), and interpersonal problems (e.g., low social support). Time 1 interpersonal violence history, externalizing behaviors, and association with deviant peers were the best predictors of subsequent violence, but did not further increase the likelihood of PTSD in response to violence. Race/ethnicity, thought disorder symptoms, and social problems were distinctly predictive of the development of PTSD following violence exposure. Among youth exposed to violence, Time 1 risk factors did not predict specific event features associated with elevated PTSD rates (e.g., parent as perpetrator), nor did interactions between Time 1 factors and event features add significantly to the prediction of PTSD diagnosis. Findings highlight areas for refinement in adolescent PTSD symptom measures and conceptualization, and provide direction for more targeted prevention and intervention efforts.

  12. Occupation and factors associated with exposure to the sun among beach workers

    Directory of Open Access Journals (Sweden)

    Eudes Euler de Souza Lucena

    2014-04-01

    Full Text Available Subjects were selected from five urban beaches to characterize the type of work conducted on urban beaches in the city of Natal, state of Rio Grande do Norte, Brazil, and determine potential associated factors among workers exposed to the sun. Data collection was based on a validated questionnaire. Results were obtained for 362 workers. Individuals were predominantly male (72.6% who worked under direct exposure to the sun (87.8%. Almost 95% had no more than 6 years of schooling and 87.91% earned an average monthly income of $318.75 dollars or more. Photoprotection was reported by 80.1%, among which sunscreen and caps/hats were predominant. Around 25% smoked and more than half did not consume alcohol. Male gender, no more than 6 years of schooling, daily exposure for up to 6 hours and use of photoprotection were the factors associated with the outdoor work category.

  13. Influence of Electron Irradiation Factor on Haruan Traditional Extract (HTE) for Oral Drug Delivery

    International Nuclear Information System (INIS)

    Ibrahim Ijang; Abdul Manan, M.J.; Kamaruddin Hashim

    2014-01-01

    Haruan or Channa striatus is source of protein, Haruan extract is well known in the region for having a medicinal quality and widely consumed. It is great advantage if this product could be administered by oral rather than injection because oral route of drug delivery is still preferred by the vast majority of patients. However protein and peptides can be denatured or degraded by conditions included the acidic pH of the stomach and presence of endogenous enzymes. In order to protect or prevent digestion and degradation of the protein in the stomach and to ensure the protein reach to gastro intestinal (GI) tract, CMS nano gel system was developed using electron irradiation method. However stability of HTE toward radiation needed to be ensured before being used for the next level. In this study, the HTE was radiated with electron radiation. Its stability was analysed in term of physical aspect by looking at the colour difference, melting point by using Differential Scanning Calorimetry (DSC) and in terms of chemical aspect which include molecular bonds by using Fourier Transform Infrared (FTIR). The results of this study were that no apparent colour difference was seen on the HTE before and after irradiation. Those are supported by FTIR and DSC analysis results that showed that there were no change of molecular bonds and melting point, compared between no irradiation and irradiation HTE during electron irradiation up to 10 kGy. Statistically the test showed no significant difference at p<0.005 within melting temperatures. (author)

  14. Effects of prolonged exposure to space flight factors for 175 days on lettuce seeds

    International Nuclear Information System (INIS)

    Nevzgodina, L.V.; Maximova, E.N.; Akatov, Yu.A.

    1981-01-01

    The effects of prolonged (up to 175 days) exposure of Lactuca sativa seeds to space flight factors, including primary cosmic radiation heavy ions have been studied. The data obtained evidence a significant fourfold increase of spontaneous mutagenesis in seeds both with regard to the total number of aberrant cells as well as the formation of single cells with multiple aberrations. Comparison of the present experiment with earlier works shows that the frequency of such aberrations increases with the duration of the flight

  15. Risk factors for mercury exposure of children in a rural mining town in northern Chile.

    Directory of Open Access Journals (Sweden)

    Johan Ohlander

    Full Text Available Traditional gold mining is associated with mercury exposure. Especially vulnerable to its neurotoxic effects is the developing nervous system of a child. We aimed to investigate risk factors of mercury exposure among children in a rural mining town in Chile.Using a validated questionnaire distributed to the parents of the children, a priori mercury risk factors, potential exposure pathways and demographics of the children were obtained. Mercury levels were measured through analyzing fingernail samples. Logistic regression modeling the effect of risk factors on mercury levels above the 75(th percentile were made, adjusted for potential confounders.The 288 children had a mean age of 9.6 years (SD = 1.9. The mean mercury level in the study population was 0.13 µg/g (SD 0.11, median 0.10, range 0.001-0.86 µg/g. The strongest risk factor for children's odds of high mercury levels (>75(th percentile, 0.165 µg/g was to play inside a house where a family member worked with mercury (OR adjusted 3.49 95% CI 1.23-9.89. Additionally, children whose parents worked in industrial gold mining had higher odds of high mercury levels than children whose parents worked in industrial copper mining or outside mining activities.Mercury exposure through small-scale gold mining might affect children in their home environments. These results may further help to convince the local population of banning mercury burning inside the households.

  16. Effects of methylandrostenediol and a lymphostimulatory thymic factor (leucotrofin) on the reactivity of adrenal cortex of X-irradiated A2G mice

    International Nuclear Information System (INIS)

    Abraham, A.D.; Rusu, V.M.; Borsa, M.; Uray, Z.; Banu, C.

    1982-01-01

    Administration of methylandrostenediol alone or with Leucotrofin to whole-body irradiated A2G mice was associated with the diminuation of some enzymatic reactions in the zona fasciculata of the adrenals after 30 days on irradiation in comparison with the irradiated controls. The incorporation rate of (2- 14 C)acetate into free cholesterol and glucocorticoid, de novo synthesized in the adrenals of the protected mice, was decreased compared to the untreated animals. These data showed that late irradiation damage - caused by enhanced synthesis and secretion of catabolic corticosteroids - could be prevented by administration of anabolic steroids and lymphostimulatory thymic factors, which protect the lymphoid system from lymphotoxic agents. (author)

  17. Effects of methylandrostenediol and a lymphostimulatory thymic factor (leucotrofin) on the reactivity of adrenal cortex of X-irradiated A2G mice

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, A.D.; Rusu, V.M.; Borsa, M.; Uray, Z.; Banu, C. (Biological Research Centre, Cluj (Romania))

    1982-03-01

    Administration of methylandrostenediol alone or with Leucotrofin to whole-body irradiated A2G mice was associated with the diminuation of some enzymatic reactions in the zona fasciculata of the adrenals after 30 days on irradiation in comparison with the irradiated controls. The incorporation rate of (2-/sup 14/C)acetate into free cholesterol and glucocorticoid, de novo synthesized in the adrenals of the protected mice, was decreased compared to the untreated animals. These data showed that late irradiation damage - caused by enhanced synthesis and secretion of catabolic corticosteroids - could be prevented by administration of anabolic steroids and lymphostimulatory thymic factors, which protect the lymphoid system from lymphotoxic agents.

  18. Influence of various factors on individual radiation exposure from the chernobyl disaster

    Directory of Open Access Journals (Sweden)

    Bondar Alexandra

    2002-10-01

    Full Text Available Abstract Background The explosion at the Chernobyl Nuclear Power Plant was one of the greatest known nuclear disasters of the 20th century. To reduce individual exposure to ionizing radiation the Soviet Union government introduced a number of counter-measures. This article presents a description of how historical events conspired to disrupt these efforts and affect residents in exposed areas. Methods This study employed an extensive review of data on radionuclide deposition, contamination patterns and lifestyle characteristics. Data were obtained from the Ukraine Ministry of Health and the Ukraine Research Center for Radiation Medicine. Results Data are presented on annual contamination rates in selected locales as well as data on local food consumption patterns. Historical factors including economic and political circumstances are also highlighted. Results show the diminution of individual doses between 1987 and 1991 and then an increase between 1991 and 1994 and the relationship between this increase and changes in the lifestyle of the local population. Conclusion A number of factors played direct and indirect roles in contributing to the populace's cumulative radiation exposure. Future post-contamination studies need to consider these factors when estimating individual exposures.

  19. Influence of various factors on individual radiation exposure from the Chernobyl disaster.

    Science.gov (United States)

    Zamostian, Pavlo; Moysich, Kirsten B; Mahoney, Martin C; McCarthy, Philip; Bondar, Alexandra; Noschenko, Andrey G; Michalek, Arthur M

    2002-10-29

    The explosion at the Chernobyl Nuclear Power Plant was one of the greatest known nuclear disasters of the 20th century. To reduce individual exposure to ionizing radiation the Soviet Union government introduced a number of counter-measures. This article presents a description of how historical events conspired to disrupt these efforts and affect residents in exposed areas. This study employed an extensive review of data on radionuclide deposition, contamination patterns and lifestyle characteristics. Data were obtained from the Ukraine Ministry of Health and the Ukraine Research Center for Radiation Medicine. Data are presented on annual contamination rates in selected locales as well as data on local food consumption patterns. Historical factors including economic and political circumstances are also highlighted. Results show the diminution of individual doses between 1987 and 1991 and then an increase between 1991 and 1994 and the relationship between this increase and changes in the lifestyle of the local population. A number of factors played direct and indirect roles in contributing to the populace's cumulative radiation exposure. Future post-contamination studies need to consider these factors when estimating individual exposures.

  20. Effect of gamma irradiation on lipoxygenases, trypsin inhibitor, raffinose family oligosaccharides and nutritional factors of different seed coat colored soybean (Glycine max L.)

    Energy Technology Data Exchange (ETDEWEB)

    Kumar Dixit, Amit [School of Biochemistry, Devi Ahilya University, Khandwa Road, Indore-452017 (India); Kumar, Vineet; Rani, Anita [National Research Centre for Soybean, Khandwa Road, Indore-452017 (India); Manjaya, J.G. [Board of Research in Nuclear Sciences, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Bhatnagar, Deepak, E-mail: bhatnagarbio@yahoo.co [School of Biochemistry, Devi Ahilya University, Khandwa Road, Indore-452017 (India)

    2011-04-15

    Three soybean genotypes Kalitur, Hara soya and NRC37 with black, green and yellow seed coat color, respectively, were gamma irradiated at 0.5, 2.0 and 5.0 kGy and tested for antinutritional and nutritional factors. Gamma irradiation at all doses reduced the level of lipoxygenase isomers, trypsin inhibitor (TI) and ascorbic acid in all the 3 soybean genotypes as compared to the unirradiated control. However, irradiation dose of 5.0 kGy increased the sucrose content of the soybean genotypes. No significant change was observed in oil, protein fatty acids and total tocopherol content of the 3 genotypes at any irradiation dose. It is suggested that inhibition of lipoxygenase, reduction in TI and ascorbic acid may be due to the breakage or oxidation of protein structure by the gamma irradiation. Similarly, gamma irradiation at higher doses may break glycosidic linkages in oligosaccharides to produce more sucrose and decrease the content of flatulence causing oligosaccharides.

  1. Effect of gamma irradiation on lipoxygenases, trypsin inhibitor, raffinose family oligosaccharides and nutritional factors of different seed coat colored soybean (Glycine max L.)

    International Nuclear Information System (INIS)

    Kumar Dixit, Amit; Kumar, Vineet; Rani, Anita; Manjaya, J.G.; Bhatnagar, Deepak

    2011-01-01

    Three soybean genotypes Kalitur, Hara soya and NRC37 with black, green and yellow seed coat color, respectively, were gamma irradiated at 0.5, 2.0 and 5.0 kGy and tested for antinutritional and nutritional factors. Gamma irradiation at all doses reduced the level of lipoxygenase isomers, trypsin inhibitor (TI) and ascorbic acid in all the 3 soybean genotypes as compared to the unirradiated control. However, irradiation dose of 5.0 kGy increased the sucrose content of the soybean genotypes. No significant change was observed in oil, protein fatty acids and total tocopherol content of the 3 genotypes at any irradiation dose. It is suggested that inhibition of lipoxygenase, reduction in TI and ascorbic acid may be due to the breakage or oxidation of protein structure by the gamma irradiation. Similarly, gamma irradiation at higher doses may break glycosidic linkages in oligosaccharides to produce more sucrose and decrease the content of flatulence causing oligosaccharides.

  2. Investigation of electron beam irradiation effects on anti-nutritional factors, chemical composition and digestion kinetics of whole cottonseed, soybean and canola seeds

    Science.gov (United States)

    Ebrahimi-Mahmoudabad, S. R.; Taghinejad-Roudbaneh, M.

    2011-12-01

    This study was completed to determine effects of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on anti-nutritional factors, ruminal degradation and in vitro crude protein (CP) digestibility of whole cottonseed (WCS), soybean (SB) and canola seeds (CS). EB-irradiation eliminated completely ( Pcontent of CS. Trypsin inhibitor activity of 15, 30 and 45 kGy EB-irradiated SB was decreased by 19, 73 and 88%, respectively. Free gossypol content of WCS was reduced linearly ( P<0.001) by irradiation. EB-irradiation increased linearly ( P<0.001) CP digestibility of feeds. In conclusion, EB-irradiation was an effective processing method for improving the nutritive value of WCS, SB and CS.

  3. G2M arrest and apoptosis in murine T lymphoma cells following exposure to 212Bi alpha particle irradiation

    International Nuclear Information System (INIS)

    Palayoor, S.T.; Humm, J.L.; Macklis, R.M.

    1993-01-01

    Asynchronous exponentially growing EL4 murine T lymphoma cells were exposed either to high LET α-radiation from 212 Bi-DTPA or to γ-radiation from a 137 Cs source. Radiation-induced cell cycle perturbation was studied by flow cytometry. Alpha irradiation, like γ, transiently arrested cells in the G2M phase in a dose-dependent manner. The maximum percentages of cells accumulated in G2M 18 h after α- and γ-irradiation were comparable, though the dose-response relationships differed. The ''RBE'' value for G2M block for α- versus γ-radiation was approx. 4. (author)

  4. Impact of some field factors on inhalation exposure levels to bitumen emissions during road paving operations.

    Science.gov (United States)

    Deygout, François; Auburtin, Guy

    2015-03-01

    Variability in occupational exposure levels to bitumen emissions has been observed during road paving operations. This is due to recurrent field factors impacting the level of exposure experienced by workers during paving. The present study was undertaken in order to quantify the impact of such factors. Pre-identified variables currently encountered in the field were monitored and recorded during paving surveys, and were conducted randomly covering current applications performed by road crews. Multivariate variance analysis and regressions were then used on computerized field data. The statistical investigations were limited due to the relatively small size of the study (36 data). Nevertheless, the particular use of the step-wise regression tool enabled the quantification of the impact of several predictors despite the existing collinearity between variables. The two bitumen organic fractions (particulates and volatiles) are associated with different field factors. The process conditions (machinery used and delivery temperature) have a significant impact on the production of airborne particulates and explain up to 44% of variability. This confirms the outcomes described by previous studies. The influence of the production factors is limited though, and should be complemented by studying factors involving the worker such as work style and the mix of tasks. The residual volatile compounds, being part of the bituminous binder and released during paving operations, control the volatile emissions; 73% of the encountered field variability is explained by the composition of the bitumen batch. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  5. Using the SRQ–20 Factor Structure to Examine Changes in Mental Distress Following Typhoon Exposure

    Science.gov (United States)

    Stratton, Kelcey J.; Richardson, Lisa K.; Tran, Trinh Luong; Tam, Nguyen Thanh; Aggen, Steven H.; Berenz, Erin C.; Trung, Lam Tu; Tuan, Tran; Buoi, La Thi; Ha, Tran Thu; Thach, Tran Duc; Amstadter, Ananda B.

    2014-01-01

    Empirical research is limited regarding postdisaster assessment of distress in developing nations. This study aimed to evaluate the factor structure of the 20-item Self-Reporting Questionnaire (SRQ–20) before and after an acute trauma, Typhoon Xangsane, in order to examine changes in mental health symptoms in an epidemiologic sample of Vietnamese adults. The study examined a model estimating individual item factor loadings, thresholds, and a latent change factor for the SRQ–20's single “general distress” common factor. The covariates of sex, age, and severity of typhoon exposure were used to evaluate the disaster-induced changes in SRQ–20 scores while accounting for possible differences in the relationship between individual measurement scale items and the latent mental health construct. Evidence for measurement noninvariance was found. However, allowing sex and age effects on the pre-typhoon and post-typhoon factors accounted for much of the noninvariance in the SRQ–20 measurement structure. A test of no latent change failed, indicating that the SRQ–20 detected significant individual differences in distress between pre- and post-typhoon assessment. Conditioning on age and sex, several typhoon exposure variables differentially predicted levels of distress change, including evacuation, personal injury, and peri-event fear. On average, females and older individuals reported higher levels of distress than males and younger individuals, respectively. The SRQ–20 is a valid and reasonably stable instrument that may be used in postdisaster contexts to assess emotional distress and individual changes in mental health symptoms. PMID:24512425

  6. Exposure Buildup Factors for Heavy Metal Oxide Glass: A Radiation Shield

    DEFF Research Database (Denmark)

    Manonara, S. R.; Hanagodimath, S. M.; Gerward, Leif

    2011-01-01

    Gamma ray exposure buildup factors for three Heavy Metal Oxide (HMO) glass systems, viz. PbO-Bi2O3-B2O3, PbO-B2O3, and Bi2O3-B2O3 glasses are presented. The computations were done by interpolation method using the Geometric Progression fitting formula and ANSI/ANS-6.4.3 library for the energy ran...... of graphs. Buildup factors of these HMO glasses cannot be found in any standard database, but they are useful for practical calculations in gamma ray shield designs, and they also, help to determine and control the thickness of the shielding material used.......Gamma ray exposure buildup factors for three Heavy Metal Oxide (HMO) glass systems, viz. PbO-Bi2O3-B2O3, PbO-B2O3, and Bi2O3-B2O3 glasses are presented. The computations were done by interpolation method using the Geometric Progression fitting formula and ANSI/ANS-6.4.3 library for the energy range...... from 0.015 to 15 MeV, up to penetration depths of 40 mfp (mean free path). The buildup factors have been studied as functions of incident photon energy and penetration depth. The variations in the buildup factor, for all the glass systems, in different energy regions; have been presented in the form...

  7. Hypoxia-Inducible Factor Pathway Inhibition Resolves Tumor Hypoxia and Improves Local Tumor Control After Single-Dose Irradiation

    International Nuclear Information System (INIS)

    Helbig, Linda; Koi, Lydia; Brüchner, Kerstin; Gurtner, Kristin; Hess-Stumpp, Holger; Unterschemmann, Kerstin; Pruschy, Martin

    2014-01-01

    Purpose: To study the effects of BAY-84-7296, a novel orally bioavailable inhibitor of mitochondrial complex I and hypoxia-inducible factor 1 (HIF-1) activity, on hypoxia, microenvironment, and radiation response of tumors. Methods and Materials: UT-SCC-5 and UT-SCC-14 human squamous cell carcinomas were transplanted subcutaneously in nude mice. When tumors reached 4 mm in diameter BAY-84-7296 (Bayer Pharma AG) or carrier was daily administered to the animals. At 7 mm tumors were either excised for Western blot and immunohistologic investigations or were irradiated with single doses. After irradiation animals were randomized to receive BAY-84-7296 maintenance or carrier. Local tumor control was evaluated 150 days after irradiation, and the dose to control 50% of tumors (TCD 50 ) was calculated. Results: BAY-84-7296 decreased nuclear HIF-1α expression. Daily administration of inhibitor for approximately 2 weeks resulted in a marked decrease of pimonidazole hypoxic fraction in UT-SCC-5 (0.5% vs 21%, P 50 , with an enhancement ratio of 1.37 (95% confidence interval [CI] 1.13-1.72) in UT-SCC-5 and of 1.55 (95% CI 1.26-1.94) in UT-SCC-14. BAY-84-7296 maintenance after irradiation did not further decrease TCD 50 . Conclusions: BAY-84-7296 resulted in a marked decrease in tumor hypoxia and substantially reduced radioresistance of tumor cells with the capacity to cause a local recurrence after irradiation. The data suggest that reduction of cellular hypoxia tolerance by BAY-84-7296 may represent the primary biological mechanism underlying the observed enhancement of radiation response. Whether this mechanism contributes to the improved outcome of fractionated chemoradiation therapy warrants further investigation

  8. Evaluation of the validity of job exposure matrix for psychosocial factors at work.

    Directory of Open Access Journals (Sweden)

    Svetlana Solovieva

    Full Text Available To study the performance of a developed job exposure matrix (JEM for the assessment of psychosocial factors at work in terms of accuracy, possible misclassification bias and predictive ability to detect known associations with depression and low back pain (LBP.We utilized two large population surveys (the Health 2000 Study and the Finnish Work and Health Surveys, one to construct the JEM and another to test matrix performance. In the first study, information on job demands, job control, monotonous work and social support at work was collected via face-to-face interviews. Job strain was operationalized based on job demands and job control using quadrant approach. In the second study, the sensitivity and specificity were estimated applying a Bayesian approach. The magnitude of misclassification error was examined by calculating the biased odds ratios as a function of the sensitivity and specificity of the JEM and fixed true prevalence and odds ratios. Finally, we adjusted for misclassification error the observed associations between JEM measures and selected health outcomes.The matrix showed a good accuracy for job control and job strain, while its performance for other exposures was relatively low. Without correction for exposure misclassification, the JEM was able to detect the association between job strain and depression in men and between monotonous work and LBP in both genders.Our results suggest that JEM more accurately identifies occupations with low control and high strain than those with high demands or low social support. Overall, the present JEM is a useful source of job-level psychosocial exposures in epidemiological studies lacking individual-level exposure information. Furthermore, we showed the applicability of a Bayesian approach in the evaluation of the performance of the JEM in a situation where, in practice, no gold standard of exposure assessment exists.

  9. Evaluation of the validity of job exposure matrix for psychosocial factors at work.

    Science.gov (United States)

    Solovieva, Svetlana; Pensola, Tiina; Kausto, Johanna; Shiri, Rahman; Heliövaara, Markku; Burdorf, Alex; Husgafvel-Pursiainen, Kirsti; Viikari-Juntura, Eira

    2014-01-01

    To study the performance of a developed job exposure matrix (JEM) for the assessment of psychosocial factors at work in terms of accuracy, possible misclassification bias and predictive ability to detect known associations with depression and low back pain (LBP). We utilized two large population surveys (the Health 2000 Study and the Finnish Work and Health Surveys), one to construct the JEM and another to test matrix performance. In the first study, information on job demands, job control, monotonous work and social support at work was collected via face-to-face interviews. Job strain was operationalized based on job demands and job control using quadrant approach. In the second study, the sensitivity and specificity were estimated applying a Bayesian approach. The magnitude of misclassification error was examined by calculating the biased odds ratios as a function of the sensitivity and specificity of the JEM and fixed true prevalence and odds ratios. Finally, we adjusted for misclassification error the observed associations between JEM measures and selected health outcomes. The matrix showed a good accuracy for job control and job strain, while its performance for other exposures was relatively low. Without correction for exposure misclassification, the JEM was able to detect the association between job strain and depression in men and between monotonous work and LBP in both genders. Our results suggest that JEM more accurately identifies occupations with low control and high strain than those with high demands or low social support. Overall, the present JEM is a useful source of job-level psychosocial exposures in epidemiological studies lacking individual-level exposure information. Furthermore, we showed the applicability of a Bayesian approach in the evaluation of the performance of the JEM in a situation where, in practice, no gold standard of exposure assessment exists.

  10. Determination of photon conversion factors relating exposure and dose for several extremity phantom designs

    International Nuclear Information System (INIS)

    Roberson, P.L.; Eichner, F.N.; Reece, W.D.

    1986-09-01

    This report presents the results of measurements of dosimetric properties of simple extremity phantoms suitable for use in extremity dosimeter performance testing. Two sizes of phantoms were used in this study. One size represented the forearm or lower leg and the other size represented the finger or toe. For both phantom sizes, measurements were performed on solid plastic phantoms and on phantoms containing simulated bone material to determine the effect of backscattered radiations from the bone on the surface dose. Exposure-to-dose conversion factors (C/sub x/ factors) were determined for photon energies ranging from 16 to 1250 keV (average for 60 Co). The effect of the presence of a phantom was also measured for a 90 Sr/ 90 Y source. Significant differences in the measured C/sub x/ factors were found among the phantoms investigated. The factors for the finger-sized phantoms were uniformly less than for the arm-sized phantoms

  11. Risk factors of distant metastasis in patients with squamous cell carcinoma of the uterine cervix treated with postoperative irradiation

    International Nuclear Information System (INIS)

    Yokoyama, Takashi; Beppu, Michiko; Kawakami, Yousuke; Nogawa, Takayoshi; Chiba, Take; Hiura, Masamichi

    2000-01-01

    This paper reports the results of a study of risk factors for recurrence in non-irradiated sites in patients with squamous cell carcinoma of the uterine cervix who received postoperative irradiation. It also discusses clinical experience with such patients, particularly those with a poor prognosis, based on a review of the literature. The study was conducted at the National Shikoku Cancer Center in 62 patients with squamous cell carcinoma of the uterine cervix (mean age=50.5, range=30-66) who received 10 MeV postoperative irradiation with a Linac between 1981 and 1990. An analysis was performed in terms of sites and times of recurrence, risk factors for distant metastasis, and groups at high risk for distant metastasis. Based on the results of the study as well as the review of the literature, it was concluded that squamous cell carcinoma of the uterine cervix is sensitive to radiation therapy and that the clinical outcome of local treatment is satisfactory. However, systemic chemotherapy should be considered for patients who are suspected of having minute distant metastasis at the time of surgical operation, i.e., those with moderate to severe vascular space invasion, multiple lymph node metastasis, parametrium infiltration, and/or endometrial infiltration. (K.H.)

  12. Characterization of the factors having an influence on the evolution of the EPR signal of irradiated alanine

    International Nuclear Information System (INIS)

    Feaugas-Le-Berre, Valerie

    1999-01-01

    EPR/alanine dosimetry has been used by the LNHB (Laboratoire National Henri Becquerel) since many years for applied metrology. This technic is based on the measurement of the EPR signal of the free radicals induced in alanine by irradiation. The aim of this work is to characterize the factors having an influence on the evolution of the amplitude of the EPR signal of irradiated alanine to limit the uncertainties on the determination of the absorbed dose. The first step of this work has been the choice of the dosimeter. A bibliographic study completed by experiments on the response of alanine isomers to the dose and on its stability with time has lead us to choose L-α-alanine powder as dosimeter. The influence of the recording parameter of the spectrometer on the characteristics of the EPR spectrum has then been studied. This has enabled us to optimize the recording conditions of EPR spectra. As the angular anisotropy of the EPR signal limits the measurements reproducibility, an experimental protocol has been defined to solve this problem. The repeatability of the measurements has been enhanced by modifying the spectrometer and using an internal standard constituted of single crystals of CuSO 4 .5H 2 O. As the amplitude of the EPR signal is sensitive to the measurement temperature, a method of normalization of the results to 20 C has been determined. We have studied the influence of an irradiation parameter and of environmental parameters. We have shown that the EPR signal amplitude increases with irradiation temperature. The EPR signal amplitude and its evolution vary strongly with storage conditions (temperature and moisture) of the dosimeter before and after irradiation. The presence of moisture in alanine powder leads to a loss of signal amplitude. The dosimeters exposition to light also entails a loss of amplitude. Oxygen does not influence the EPR spectrum of alanine. We have noticed that the EPR signal amplitude of samples stored in absence of moisture

  13. Factors affecting occupational exposure to needlestick and sharps injuries among dentists in Taiwan: a nationwide survey.

    Directory of Open Access Journals (Sweden)

    Hsin-Chung Cheng

    Full Text Available BACKGROUND: Although the risks of needlestick and sharps injuries (NSIs for dentists are well recognized, most papers published only described the frequency of occupational exposure to NSIs. Less has been reported assessing factors contributing to exposure to NSIs. The purpose of this study was to update the epidemiology of NSIs among dentists in Taiwan and identify factors affecting NSIs in order to find preventive strategies. METHODOLOGY/PRINCIPAL FINDINGS: A nationwide survey was conducted in dentists at 60 hospitals and 340 clinics in Taiwan. The survey included questions about factors supposedly affecting exposure to NSIs, such as dentist and facility characteristics, knowledge and attitudes about infectious diseases, and practices related to infection control. Univariate and multivariate logistic regression analyses were conducted to determine the association between risk factors and exposure to NSIs. In total, 434 (74.8% of 580 dentists returned the survey questionnaires, and 100 (23.0% reported that they had experienced more than one NSI per week. Our data showed that the risk of occupational NSIs is similarly heightened by an older age (odds ratio [OR], 3.18; 95% confidence interval [CI], 1.62-6.25, more years in practice (OR, 2.57; 95% CI, 1.41-4.69, working in clinics (OR, 1.73; 95% CI, 1.08-2.77, exhibiting less compliance with infection-control procedures (OR, 1.82; 95% CI, 1.04-3.18, having insufficient knowledge of blood-borne pathogens (OR, 1.67; 95% CI, 1.04-2.67, and being more worried about being infected by blood-borne pathogens (OR, 1.82; 95% CI, 1.05-3.13. CONCLUSIONS/SIGNIFICANCE: High rates of NSIs and low compliance with infection-control procedures highly contribute to the chance of acquiring a blood-borne pathogen infection and threaten occupational safety. This study reveals the possible affecting factors and helps in designing prevention strategies for occupational exposure to NSIs.

  14. Sensitivity difference between anterior and posterior lobes of rat cerebellum to prenatal exposure to 2.5 Gy X-irradiation. A histological study

    International Nuclear Information System (INIS)

    Darmanto, W.; Hayasaka, Shizu; Takagishi, Yoshiko; Aolad, H.M.; Inouye, Minoru

    1997-01-01

    We investigated the histological differences in abnormality between anterior lobes (vermian lobules II, III and culmen IV, V) and posterior lobes (lobules IX, X) of the rat cerebellum following prenatal exposure to X-irradiation. Pregnant rats were exposed to 2.5 Gy X-irradiation at gestation day-21 (GD-21), and pups were sacrificed from birth through 15 days of age. Their cerebella were examined histologically and immunohistochemically for glial fibrillary acidic protein in Bergmann fibers. Extensive cell death was found in the external granular layer (EGL) of the cerebellum on the day of birth. In the anterior lobes, the number of cell deaths was higher than in the posterior lobes. During 5 days after birth, the recovery of EGL was earlier in the posterior lobes than in the anterior lobes. Seven days after birth, Bergmann fibers were more irregular in the anterior lobes than in the posterior lobes. The number of Purkinje cells in ectopic locations was higher in the anterior lobes than in the posterior lobes. The EGL and migrating Purkinje cells showed different responses to X-irradiation in the anterior than in the posterior lobes of the cerebellum. (author)

  15. Proteomic analysis of a model unicellular green alga, Chlamydomonas reinhardtii, during short-term exposure to irradiance stress reveals significant down regulation of several heat-shock proteins.

    Science.gov (United States)

    Mahong, Bancha; Roytrakul, Suttiruk; Phaonaklop, Narumon; Wongratana, Janewit; Yokthongwattana, Kittisak

    2012-03-01

    Oxygenic photosynthetic organisms often suffer from excessive irradiance, which cause harmful effects to the chloroplast proteins and lipids. Photoprotection and the photosystem II repair processes are the mechanisms that plants deploy to counteract the drastic effects from irradiance stress. Although the protective and repair mechanisms seemed to be similar in most plants, many species do confer different level of tolerance toward high light. Such diversity may originate from differences at the molecular level, i.e., perception of the light stress, signal transduction and expression of stress responsive genes. Comprehensive analysis of overall changes in the total pool of proteins in an organism can be performed using a proteomic approach. In this study, we employed 2-DE/LC-MS/MS-based comparative proteomic approach to analyze total proteins of the light sensitive model unicellular green alga Chlamydomonas reinhardtii in response to excessive irradiance. Results showed that among all the differentially expressed proteins, several heat-shock proteins and molecular chaperones were surprisingly down-regulated after 3-6 h of high light exposure. Discussions were made on the possible involvement of such down regulation and the light sensitive nature of this model alga.

  16. Prenatal exposure to lead in Spain: cord blood levels and associated factors.

    Science.gov (United States)

    Llop, Sabrina; Aguinagalde, Xabier; Vioque, Jesus; Ibarluzea, Jesús; Guxens, Mònica; Casas, Maribel; Murcia, Mario; Ruiz, María; Amurrio, Ascensión; Rebagliato, Marisa; Marina, Loreto Santa; Fernandez-Somoano, Ana; Tardon, Adonina; Ballester, Ferran

    2011-05-01

    Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. ≥ vs < 2μg/dL). A low percentage of cord blood samples with lead levels ≥ 2μg/dL were found (5.9%). Geometric mean and maximum were 1.06μg/dL and 19μg/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels ≥ 2μg/dL. In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Television exposure as a risk factor for aggressive behavior among 3-year-old children.

    Science.gov (United States)

    Manganello, Jennifer A; Taylor, Catherine A

    2009-11-01

    To examine associations of child television (TV) exposure and household TV use with aggressive behavior among 3-year-old children while controlling for demographic characteristics and risk and protective factors for aggression. The Fragile Families and Child Wellbeing Study, a prospective cohort study. Data collected at home and by telephone from parents of children born from 1998 to 2000 from 20 cities. Mothers who completed a 36-month in-home survey and met inclusion criteria (n = 3128). Direct child TV exposure and household TV use were the primary explanatory variables. Additional risk factors included neighborhood disorder and maternal factors like depression. Childhood aggression was assessed with the Child Behavior Checklist/2-3. Multivariate linear regression models were used to examine associations between TV measures, additional risk factors, and childhood aggression. Children who were spanked in the past month (beta = 1.24, P < .001), lived in a disorderly neighborhood (beta = 2.07, P < .001), and had a mother reporting depression (beta = 0.92, P < .001) and parenting stress (beta = 0.16, P < .001) were significantly more likely to exhibit aggressive behavior. Direct child TV exposure (beta = 0.16, P < .001) and household TV use (beta = 0.09, P < .001) were also significantly associated with childhood aggression, even when controlling for other factors. Three-year-old children exposed to more TV, both directly and indirectly, are at increased risk for exhibiting aggressive behavior. Further research is essential to determine whether pediatric recommendations concerning TV and children should include limits for general household TV use.

  18. Radiographic changes following radiotherapy in the patients with lung cancer. Is the irradiated area of the mediastinum in the simulation film a significant factor?

    International Nuclear Information System (INIS)

    Yamazaki, H.; Tang, J.T.; Inoue, T.; Teshima, T.; Ohtani, M.; Itou, M.; Takeuchi, E.; Inoue, T.

    1995-01-01

    To evaluate the significance of the irradiated area of the mediastinum in the simulation film for radiation induced lung injury. A total of 208 patients with primary lung cancer treated with radiation therapy were analyzed for incidence of radiation induced lung injury. Lung injury was defined as the appearance of an abnormal shadow on the chest radiograph. CT images were used to differentiate recurrence or other conditions. Age, sex, irradition dose, irradiated lung area, T and N factors of the tumor, irradiated mediastinum area, performance status of patients, location of irradiated fields and use of chemotherapy were analyzed with Cox's multivariate regression model. The cumulative rate of radiation induced lung injury at 12 months was 85%. Significant factor of radiation induced lung injury was irradiated area of the mediastinum (p=0.03). Irradiated area of the lung (p=0.18, n.s.), total tumor dose (p=0.1, n.s.), use of chemotherapy (p=0.08, n.s.) and location of irradiated field (p=0.08, n.s.) may also have an effect on radiation induced lung injury. The irradiated area of the mediastinum is one of the significant factors in radiation induced lung injury. (orig.) [de

  19. The concentration of oxygen dissolved in tissues at the time of irradiation as a factor in radiotherapy

    International Nuclear Information System (INIS)

    Gray, L.H.; Conger, A.D.; Ebert, M.; Hornsey, S.; Scott, O.C.A.

    1984-01-01

    The sensitivity of tumour cells to X rays has been shown to be about three times as great when irradiated in a well-oxygenated medium as under anoxic conditions. The manner in which sensitivity depends on oxygen tension closely resembles that found by other workers for plant and insect tissues. The sensitivity of the tumour cells to fast neutron radiation is only slightly affected by oxygen tension. Consideration is given to the supply of oxygen to tissues as a factor in radiotherapy, and it is concluded on the basis of existing knowledge that in certain circumstances the effectiveness of X-ray treatment might be increased if the patient were breathing oxygen at the time of irradiation

  20. Factors contribution to the reduction of occupational exposures at Dukovany NPP

    International Nuclear Information System (INIS)

    Petrova, K.; Urbancik, L.; Fuchsova, D.; Kulich, V.

    2008-01-01

    This paper describes the causes of achieving such low collective doses and the ways used for a further optimization process reducing occupational exposure at the Dukovany NPP from the beginning of operation up to now. The objective of this contribution is to explain the approaches leading to reduced occupational radiation exposure, measures which have been implemented and what is needed for the maintenance of excellent results in the future. It is possible to identify three main areas and eight main sources affecting collective dose values. There are one objective and two specific causes for low exposures: 1. Objective cause: - General arrangement; - Structural materials; - Fuel integrity. 2. Specific cause influenced by the state regulation: - Legislative support; - Operational safety culture; - Well-though tout system of radiological monitoring; - Effective radiological event feedback; - Effective education and training. 3. Specific cause uninfluenced by the state regulation: - Modified water chemistry of the primary circuit adopted by the licensee; - Licensee's system of radiation work debriefing. All the items specified above contribute to a unique concurrence of circumstances leading to the constantly low occupational exposures at the Czech nuclear power plants. The paper discusses all factors involved in these good results. (authors)

  1. Analysis of the dose-response relationships of chromosomal aberrations after irradiation and bleomycin exposure of different human lymphocyte fractions in vitro

    International Nuclear Information System (INIS)

    Dresp, J.

    1979-01-01

    Cytogenetic analyses could be carried out on whole blood and pure T-cell cultures and also on cells of the 'buffy-coat'. In pure B-cell cultures even after 96 hours no mitogenic stimulation could be achieved. Parameters of radiosensitivity and bleomycin sensitivity were dicentric chromosomes, for which the dose-response relationships were calculated. Chromosomal investigations on the 'buffy-coat' cells did not provide indications referring to a varying radiosensitivity compared to whole blood cultures. In pure T-cell cultures T-lymphocytes, which had been separated after whole blood irradiation exposure, showed lower aberration rates than lymphocytes, which had been cultured after whole blood irradiation without previous separation. In the case of bleomycin exposure the treatment of previously separated leucocytes and T-lymphocytes respectively, led to lower aberration rates than the treatment before separation. Therefore it is apparently not necessary for a cytogenetic dosimetry or mutagenicity to depart from the whole blood culture method. (orig./MG) [de

  2. The acute effects of alpha and beta irradiation of mouse skin and the factors affecting the response

    International Nuclear Information System (INIS)

    Needham, S.G.; Coggle, J.E.

    1991-01-01

    Several problems regarding acute effects of alpha and beta irradiation were investigated in order to clarify protection problems of localised doses to the skin. A study into the acute biological effects of different energy beta emitters and the effects of energy and area on the response showed direct relationships between these criteria for a range of different acute responses with different time courses. Three different types of acute response were found and these are described as 'moist desquamation', 'acute ulceration' and 'acute epidermal necrosis'. An unexpected finding was that the lower energy beta emitter 170 Tm was as efficient at inducing scab formation as the higher energy 90 Sr sources for the same area of exposure. Experiments using 2x4 cm 2 exposures to 224 Cm alpha particles showed that the response to this poorly penetrating radiation was minimal after doses as high as 180 Gy measured at 10 μm into the skin. In comparison, large area exposure to 170 Tm produced areas of prolonged scabbing after doses up to 100 Gy. However, the intensity of the reaction varied between strains. (author)

  3. Effect of granulocyte colony-stimulating factor on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation

    International Nuclear Information System (INIS)

    Zhao Hongxia; Guo Mei; Sun Xuedong; Ai Huisheng

    2011-01-01

    Objective: To investigate the effects of recombinant human granulocyte colony stimulating factor (G-CSF) on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation. Methods: Female BALB/c mice were irradiated with a 6.0 Gy of γ-ray total-body irradiation and then randomly divided into GCSF group and control group. For mice in the GCSF group, recombinant human G-CSF 100 μg · kg -1 · d -1 was injected subcutaneously once daily for 14 continuous days and mice in the control group were given the same volume of phosphate buffered solution (PBS). At 7, 14, 21 and 28 days later, mice were killed and thymus mononuclear cell suspension were analyzed by flow cytometry for the percentage of the four stages of thymic CD4 - CD8 - double negative cells (DN1-4) and the CD4 + CD8 + double positive ( CD4 + CD8 + DP), CD4 + CD8 - single positive (CD4 + SP), CD4 - CD8 + single positive cells (CD8 + SP).Real-time PCR was used for detection and quantitation of murine T cell receptor rearrangement excision circles (sjTRECs) of the thymic cells of 30 and 60 d after irradiation. Results: The percentage of thymic DN1 cells in GCSF group was significantly higher than that of the control group 7 d after irradiation (t=9.59, P<0.05). 21 d later, the proportion of thymic DN3 and DN4 cells were higher than those of the control group (t=16.37, 7.6, P<0.05). The percentage of thymic CD4 + CD8 + DP cells decreased 7 d after irradiation,increased at 14 d, decreased again at 21 days,and then got a permanent recover. The percentage of thymic CD4 + CD8 + DP cells in the GCSF group recovered to normal and was significantly higher than that of the control group 28 days after irradiation (t=12.22, P<0.05). The percentage of thymic CD8 + SP cells of the GCSF group was significantly higher than that of the control group 21 d after irradiation (t=3.77, P<0.05), while G-CSF had no obvious influence on the percentage of the thymic CD4 + SP cells. The sjTRECs copies in the

  4. Influence of gamma irradiation exposure on the performance of supercapacitor electrodes made from oil palm empty fruit bunches

    International Nuclear Information System (INIS)

    Mohd Nor, Najah Syahirah; Deraman, Mohamad; Omar, Ramli; Awitdrus,; Farma, Rakhmawati; Basri, Nur Hamizah; Mohd Dolah, Besek Nurdiana; Mamat, Nurul Fatin; Yatim, Baharudin; Md Daud, Mohd Norizam

    2015-01-01

    Carbon-monolith electrodes for supercapacitors were prepared from GMs (green monoliths) made from pre-carbonized fibers of oil palm EFB (empty fruit bunches) and GMs of pre-carbonized EFB fibers exposed to gamma radiation at 5 kGy, 15 kGy, and 20 kGy. GMs and irradiated GMs were carbonized and activated to prepare ACM (activated-carbon-monolith) electrodes. The gamma radiation affected the pore structure of the ACM electrodes and the electrochemical performance of the supercapacitors; irradiation doses of 0 kGy, 5 kGy, 15 kGy and 20 kGy produced specific capacitances of 121 F g −1 , 196 F g −1 , 11 F g −1 , and 12 F g −1 , respectively. The irradiation dose of 5 kGy appears to be optimum and produces a specific power and specific energy of 236 W kg −1 and 5.45 W h kg −1 , respectively, representing 34% and 60% increases over ACM electrodes prepared from non-irradiated GMs. - Highlights: • Green monoliths were prepared from pre-carbonized fibers of oil palm fruit bunches. • Green monoliths were irradiated with gamma rays at doses from 5 to 20 kGy. • Green monoliths were carbonized and activated to prepare activated carbon electrodes. • A 5 kGy dosage produce the best supercapacitor electrode. • Specific power and energy improved of 34% and 60%, respectively, were obtained after the 5 kGy dosage

  5. Determining Exposure Factors of Anti-Fogging, Dye, Disinfectant, Repellent, and Preservative Products in Korea.

    Science.gov (United States)

    Lee, Daeyeop; Kim, Joo-Hyon; Kim, Taksoo; Yoon, Hyojung; Jo, Areum; Lee, Byeongwoo; Lim, Hyunwoo; Kim, Pilje; Seo, Jungkwan

    2018-01-30

    Reliable exposure factors are essential to determine health risks posed by chemicals in consumer products. We analyzed five risk-concerned product categories (anti-fogging, dye, disinfectant, repellent, and preservative products) for 13 products (three car anti-fogging products, a lens anti-fogging product, two car dye products, two drain disinfectants, an air conditioner disinfectant, a chlorine-based disinfectant, a fabric repellent, an insect repellent for food, and a wood preservative) considered to be of high risk in order to determine exposure factors via web surveys and estimation of amount of product. Among the 3000 participants (1482 (49%) men) aged ≥19 years, drain disinfectants were used most frequently (38.2%); the rate of usage of the other products ranged between 1.1-24.0%. The usage rates for the consumer products differed by sex, age, income, and education. Some consumer products such as car and lens anti-fogging products, chlorine-based disinfectants, fabric repellents, and drain disinfectants were regularly used more than once a month, while car dye products, air conditioner disinfectants, insect repellents for food, and wood preservatives were not regularly used owing to the specific product purposes and seasonal needs. Our results could be used for managing or controlling chemical substances in consumer products and conducting accurate exposure assessments.

  6. Community violence exposure and severe posttraumatic stress in suburban American youth: risk and protective factors.

    Science.gov (United States)

    Löfving-Gupta, Sandra; Lindblad, Frank; Stickley, Andrew; Schwab-Stone, Mary; Ruchkin, Vladislav

    2015-04-01

    The psychological effects of community violence exposure among inner-city youth are severe, yet little is known about its prevalence and moderators among suburban middle-class youth. This study aimed to assess the prevalence of community violence exposure among suburban American youth, to examine associated posttraumatic stress and to evaluate factors related to severe vs. less severe posttraumatic stress, such as co-existing internalizing and externalizing problems, as well as the effects of teacher support, parental warmth and support, perceived neighborhood safety and conventional involvement in this context. Data were collected from 780 suburban, predominantly Caucasian middle-class high-school adolescents in the Northeastern US during the Social and Health Assessment (SAHA) study. A substantial number of suburban youth were exposed to community violence and 24% of those victimized by community violence developed severe posttraumatic stress. Depressive symptoms were strongly associated with higher levels and perceived teacher support with lower levels of posttraumatic stress. Similar to urban youth, youth living in suburban areas in North American settings may be affected by community violence. A substantial proportion of these youth reports severe posttraumatic stress and high levels of comorbid depressive symptoms. Teacher support may have a protective effect against severe posttraumatic stress and thus needs to be further assessed as a potential factor that can be used to mitigate the detrimental effects of violence exposure.

  7. Exposure to psychosocial risk factors in the context of work: a systematic review

    Science.gov (United States)

    Fernandes, Cláudia; Pereira, Anabela

    2016-01-01

    ABSTRACT OBJECTIVE To analyze the scientific literature about the effects of exposure to psychosocial risk factors in work contexts. METHODS A systematic review was performed using the terms “psychosocial factors” AND “COPSOQ” in the databases PubMed, Medline, and Scopus. The period analyzed was from January 1, 2004 to June 30, 2012. We have included articles that used the Copenhagen Psychosocial Questionnaire (COPSOQ) as a measuring instrument of the psychosocial factors and the presentation of quantitative or qualitative results. German articles, psychometric studies or studies that did not analyze individual or work factors were excluded. RESULTS We included 22 articles in the analysis. Individual factors, such as gender, age, and socioeconomic status, were analyzed along with work-related factors such as labor demands, work organization and content, social relationships and leadership, work-individual interface, workplace values, justice and respect, personality, health and well-being, and offensive behaviors. We analyzed the sample type and the applied experimental designs. Some population groups, such as young people and migrants, are more vulnerable. The deteriorated working psychosocial environment is associated with physical health indicators and weak mental health. This environment is also a risk factor for the development of moderate to severe clinical conditions, predicting absenteeism or intention of leaving the job. CONCLUSIONS The literature shows the contribution of exposure to psychosocial risk factors in work environments and their impact on mental health and well-being of workers. It allows the design of practical interventions in the work context to be based on scientific evidences. Investigations in specific populations, such as industry, and studies with more robust designs are lacking. PMID:27253900

  8. Exposure to psychosocial risk factors in the context of work: a systematic review

    Directory of Open Access Journals (Sweden)

    Cláudia Fernandes

    2016-01-01

    Full Text Available ABSTRACT OBJECTIVE To analyze the scientific literature about the effects of exposure to psychosocial risk factors in work contexts. METHODS A systematic review was performed using the terms “psychosocial factors” AND “COPSOQ” in the databases PubMed, Medline, and Scopus. The period analyzed was from January 1, 2004 to June 30, 2012. We have included articles that used the Copenhagen Psychosocial Questionnaire (COPSOQ as a measuring instrument of the psychosocial factors and the presentation of quantitative or qualitative results. German articles, psychometric studies or studies that did not analyze individual or work factors were excluded. RESULTS We included 22 articles in the analysis. Individual factors, such as gender, age, and socioeconomic status, were analyzed along with work-related factors such as labor demands, work organization and content, social relationships and leadership, work-individual interface, workplace values, justice and respect, personality, health and well-being, and offensive behaviors. We analyzed the sample type and the applied experimental designs. Some population groups, such as young people and migrants, are more vulnerable. The deteriorated working psychosocial environment is associated with physical health indicators and weak mental health. This environment is also a risk factor for the development of moderate to severe clinical conditions, predicting absenteeism or intention of leaving the job. CONCLUSIONS The literature shows the contribution of exposure to psychosocial risk factors in work environments and their impact on mental health and well-being of workers. It allows the design of practical interventions in the work context to be based on scientific evidences. Investigations in specific populations, such as industry, and studies with more robust designs are lacking.

  9. Studies on the pathogenesis and survival of different culture forms of Listeria monocytogenes to pulsed UV-light irradiation after exposure to mild-food processing stresses.

    Science.gov (United States)

    Bradley, Derek; McNeil, Brian; Laffey, John G; Rowan, Neil J

    2012-06-01

    The effects of mild conventional food-processing conditions on Listeria monocytogenes survival to pulsed UV (PUV) irradiation and virulence-associated characteristics were investigated. Specifically, this study describes the inability of 10 strains representative of 3 different culture forms or morphotypes of L. monocytogenes to adapt to normally lethal levels of PUV-irradiation after exposure to sub-lethal concentrations of salt (7.5% (w/v) NaCl for 1 h), acid (pH 5.5 for 1 h), heating (48 °C for 1 h) or PUV (UV dose 0.08 μJ/cm(2)). Findings showed that the order of increasing sensitivity of L. monocytogenes of non-adapted and stressed morphotypes to low pH (pH 3.5 for 5 h, adjusted with lactic), high salt (17.5% w/v NaCl for 5 h), heating (60 °C for 1 h) and PUV-irradiation (100 pulses at 7.2 J and 12.8 J, equivalent to UV doses of 2.7 and 8.4 μJ/cm(2) respectively) was typical wild-type smooth (S/WT), atypical filamentous rough (FR) and atypical multiple-cell-chain (MCR) variants. Exposure of L. monocytogenes cells to sub-lethal acid, salt or heating conditions resulted in similar or increased susceptibility to PUV treatments. Only prior exposure to mild heat stressing significantly enhanced invasion of Caco-2 cells, whereas subjection of L. monocytogenes cells to combined sub-lethal salt, acid and heating conditions produced the greatest reduction in invasiveness. Implications of these findings are discussed. This constitutes the first study to show that pre-exposure to mild conventional food-processing stresses enhances sensitivity of different culture morphotypes of L. monocytogenes to PUV, which is growing in popularity as an alternative or complementary approach for decontamination in the food environment. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Interaction of Physical Exposures and Occupational Factors on Sickness Absence in Automotive Industry Workers.

    Science.gov (United States)

    Valirad, Fateme; Ghaffari, Mostafa; Abdi, Alireza; Attarchi, Mirsaeed; Mircheraghi, Seyed Farzin; Mohammadi, Saber

    2015-04-23

    Increased sickness absence in recent years has been a trouble making issue in industrial society. Identify the causes of sickness absence and its influencing factors, is an important step to control and reduce its associated complications and costs. The aim of this study was to evaluate main factors associated with the incidence of sickness absence. In 2012, a cross-sectional study on 758 employees of a car accessories producing company was applied and relevant information about the number of days and episodes of sickness absence, Disease resulting in absence from work, personal features, occupational factors and physical exposures were collected. To determine risk factors associated with sickness absence, Logistic regression analysis was used. The most common diseases leading to sickness absence in order of frequency were Respiratory diseases, musculoskeletal disorders, gastrointestinal diseases and injuries at work. Musculoskeletal disorders increased the danger of long term absence by 4/33 times. Blue collar and shift works were the most important occupational factors associated with the incidence of sickness absence. The main physical factors that affect incidence of sickness absence were frequent bending-twisting and heavy lifting. Identifying controllable factors of sickness absence and trying to prevent and modify them such as compliance of ergonomic principals to decrease physical can be effective in reducing sickness absence.

  11. A National Study on Nurses’ Exposure to Occupational Violence in Lebanon: Prevalence, Consequences and Associated Factors

    Science.gov (United States)

    Alameddine, Mohamad; Mourad, Yara; Dimassi, Hani

    2015-01-01

    Background Healthcare institutions have commonly reported exposure of employees, particularly nurses, to high levels of occupational violence. Despite such evidence in the Middle East Region, there is a dearth of national studies that have systematically investigated this phenomenon. This study investigates the prevalence, characteristics, consequences and factors associated with nurses’ exposure to occupational violence in Lebanon. Methods A cross-sectional design was utilized to survey a nationally representative sample of 915 nurses registered with the Order of Nurses in Lebanon. Stratified random sampling by governorate was utilized. Individually-mailed questionnaires collected information on exposure to violence, degree of burnout and demographic/professional background. The main outcome variables were exposure to verbal abuse (never, 1–3, 4–9 and 10+ times) and physical violence (never, ever) over the past 12-months. Descriptive statistics were used to estimate prevalence of violence. Multivariable, binomial and multinomial regression models were carried out to investigate the correlates of exposure to verbal abuse and physical violence, respectively. Results Response rate was 64.8%. Over the last year, prevalence of nurses’ exposure to verbal abuse was 62%, (CI: 58–65%) and physical violence was 10%, (CI: 8–13%). Among respondents, 31.7% of nurses indicated likelihood to quit their jobs and 22.3% were undetermined. Furthermore, 54.1% reported high levels of emotional exhaustion and 28.8% reported high levels of depersonalization. Compared to nurses with no exposure to verbal abuse, nurses reporting high exposure had high levels of emotional exhaustion (OR:6.4; CI:1.76–23.32), depersonalization (OR:6.8; CI: 3–15) and intention to quit job (OR:3.9; CI: 1.8–8.3). They further reported absence of anti-violence policies at their institutions (OR: 3; CI: 1.5–6.3). Nurses that were ever exposed to physical violence were more likely to be males

  12. Degradation of photovoltaic backsheet materials under multi-factor accelerated UV light exposures

    Science.gov (United States)

    Klinke, Addison G.; Gok, Abdulkerim; Ifeanyi, Silas I.; French, Roger H.; Bruckman, Laura S.

    2017-08-01

    Long term outdoor durability of photovoltaic (PV) module backsheets is critical to a module's power output over its lifetime. The use of uoropolymer-based backsheets or the addition of stabilizers to polyethylene-terephthalate (PET) and polyamide (PA) type backsheets can help extend their lifetime. This study presents the performance of 21 backsheets made of 8 different material combinations under ASTM G154 Cycle 4 accelerated light exposures. The backsheets were subjected to 4000 hours of high irradiance UVA light at a peak intensity of 1.55 W=m2 at 340 nm at 70°C with and without a condensing humidity cycle at 50°C. Backsheets were evaluated, with repeated measurements, using various evaluation techniques to identify and assess potential signs of degradation. These evaluations included the yellowness index (YI), CIE color space coordinates, and gloss at 20, 60, and 85°. The temporal evolution of the relative color change ΔE was statistically analyzed to develop a stress-response model which used the UVA light dose to predict color change. It was found that the PVF/PET/E backsheet performed the best while PET/PET/E and THV/PET/EVA backsheets performed the worst. Additionally, substantial variation in color change response, attributable to key manufacturing differences, was observed within a given material type.

  13. Alternatives to dose, quality factor and dose equivalent for low level irradiation

    International Nuclear Information System (INIS)

    Sondhaus, C.A.; Bond, V.P.; Feinendegen, L.E.

    1988-01-01

    Randomly occurring energy deposition events produced by low levels of ionizing radiation interacting with tissue deliver variable amounts of energy to the sensitive target volumes within a small fraction of the cell population. A model is described in which an experimentally derived function relating event size to cell response probability operates mathematically on the microdosimetric event size distribution characterizing a given irradiation and thus determines the total fractional number of responding cells; this fraction measures the effectiveness of the given radiation. Normalizing to equal numbers of events produced by different radiations and applying this cell response or hit size effectiveness function (HSEF) should define radiation quality, or relative effectiveness, on a more nearly absolute basis than do the absorbed dose and dose evaluation, which are confounded when applied to low level irradiations. Examples using both calculation and experimental data are presented. 15 refs., 18 figs

  14. Hypoxia-Inducible Factor Pathway Inhibition Resolves Tumor Hypoxia and Improves Local Tumor Control After Single-Dose Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Helbig, Linda [OncoRay–National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Koi, Lydia [OncoRay–National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Deutsches Konsortium für Translationale Krebsforschung, Site Dresden, Dresden (Germany); Brüchner, Kerstin [Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Institute of Radiooncology Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Gurtner, Kristin [Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Hess-Stumpp, Holger; Unterschemmann, Kerstin [Global Drug Discovery, Bayer Pharma, Berlin (Germany); Pruschy, Martin [Radiation Oncology, University of Zurich, Zurich (Switzerland); and others

    2014-01-01

    Purpose: To study the effects of BAY-84-7296, a novel orally bioavailable inhibitor of mitochondrial complex I and hypoxia-inducible factor 1 (HIF-1) activity, on hypoxia, microenvironment, and radiation response of tumors. Methods and Materials: UT-SCC-5 and UT-SCC-14 human squamous cell carcinomas were transplanted subcutaneously in nude mice. When tumors reached 4 mm in diameter BAY-84-7296 (Bayer Pharma AG) or carrier was daily administered to the animals. At 7 mm tumors were either excised for Western blot and immunohistologic investigations or were irradiated with single doses. After irradiation animals were randomized to receive BAY-84-7296 maintenance or carrier. Local tumor control was evaluated 150 days after irradiation, and the dose to control 50% of tumors (TCD{sub 50}) was calculated. Results: BAY-84-7296 decreased nuclear HIF-1α expression. Daily administration of inhibitor for approximately 2 weeks resulted in a marked decrease of pimonidazole hypoxic fraction in UT-SCC-5 (0.5% vs 21%, P<.0001) and in UT-SCC-14 (0.3% vs 19%, P<.0001). This decrease was accompanied by a significant increase in fraction of perfused vessels in UT-SCC-14 but not in UT-SCC-5. Bromodeoxyuridine and Ki67 labeling indices were significantly reduced only in UT-SCC-5. No significant changes were observed in vascular area or necrosis. BAY-84-7296 before single-dose irradiation significantly decreased TCD{sub 50}, with an enhancement ratio of 1.37 (95% confidence interval [CI] 1.13-1.72) in UT-SCC-5 and of 1.55 (95% CI 1.26-1.94) in UT-SCC-14. BAY-84-7296 maintenance after irradiation did not further decrease TCD{sub 50}. Conclusions: BAY-84-7296 resulted in a marked decrease in tumor hypoxia and substantially reduced radioresistance of tumor cells with the capacity to cause a local recurrence after irradiation. The data suggest that reduction of cellular hypoxia tolerance by BAY-84-7296 may represent the primary biological mechanism underlying the observed enhancement of

  15. Thyroid Cancer Induction: Nitrates as Independent Risk Factors or Risk Modulators after Radiation Exposure, with a Focus on the Chernobyl Accident.

    Science.gov (United States)

    Drozd, Valentina M; Branovan, Igor; Shiglik, Nikolay; Biko, Johannes; Reiners, Christoph

    2018-03-01

    In recent decades, differentiated thyroid cancer (DTC) incidence has been increasing worldwide. The important contributions to this phenomenon of "overdiagnosis" driven by wider use of improved ultrasound systems are amply documented, notwithstanding the "real" carcinogenic effects of ionizing radiation, e.g., from the Chernobyl accident or health care interventions. Less well understood is the role of nitrates - as environmental pollutants, in diet, and in medication - in thyroid carcinogenesis. Increasing exposure to nitrates is associated with rising incidence of esophageal, stomach, bladder, and colon cancers. Recent data suggest that in agricultural areas with higher mean nitrate levels in groundwater, DTC risk is also elevated. Our work in Belarus after Chernobyl has shown that children in districts with high nitrate concentrations in drinking water had significantly higher thyroid cancer incidence after irradiation than did their counterparts in areas with lower nitrate concentrations. Notwithstanding thyroid shielding, increasing use of computed tomography and dental X-rays heightens radiation exposure of the salivary glands in the general population, especially in children and adolescents. When nitrate intake is increased, salivary gland irradiation may potentially result in carcinogenic elevations in plasma nitric oxide concentrations. In conclusion, excess nitrate intake seems to be an independent risk factor for DTC. Additionally, we hypothesize from our data that high nitrate levels modulate the carcinogenic effect of radiation on the thyroid. Cohort studies, case-control studies, or both, are needed to quantify the effects of nitrates on DTC risk in the presence or absence of radiation exposure, e.g., that associated with diagnostic or therapeutic health care interventions.

  16. Intracerebral cavernous hemangioma after cranial irradiation in childhood. Incidence and risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Strenger, V.; Sovinz, P.; Lackner, H.; Dornbusch, H.J.; Moser, A.; Urban, C. [Graz Medical Univ. (Austria). Div. of Pediatric Hematology and Oncology; Lingitz, H. [Graz Medical Univ. (Austria). Dept. of Therapeutic Radiology and Oncology; Eder, H.G. [Graz Medical Univ. (Austria). Dept. of Neurosurgery

    2008-05-15

    Background and Purpose: Radiotherapy is an integral part of various therapeutic regimens in pediatric and adult oncology. Endocrine dysfunction, neurologic and psychiatric deficits, secondary malignancies and radiation-induced necrosis are well-known possible late effects of cranial irradiation. However, only sporadic cases of radiation-induced cavernous hemangiomas (RICH) have been reported so far. Patients and Methods: Pediatric patients who underwent cranial radiation therapy for malignant diseases between January 1980 and December 2003 were retrospectively analyzed. After the end of therapy they entered a detailed follow-up program. Results: Of 171 patients, eight (three patients with medulloblastoma, three patients with acute lymphoblastic leukemia, and one patient each with ependymoma and craniopharyngioma) developed intracerebral cavernoma 2.9-18.4 years after irradiation representing a cumulative incidence (according to the Kaplan-Meier method) of 2.24%, 3.86%, 4.95%, and 6.74% within 5, 10, 15, and 20 years following radiation therapy, respectively. In patients treated in the first 10 years of life, RICH occurred with shorter latency and significantly more often (p = 0.044) resulting in an even higher cumulative incidence. Conclusion: These findings and previously published cases show that cavernous hemangiomas may occur after irradiation of the brain several years after the end of therapy irrespective of the radiation dose and type of malignancy. Particularly children < 10 years of age at the time of irradiation are at higher risk. Since patients with RICH frequently do not show symptoms but hemorrhage is a possible severe complication, imaging of the central nervous system should be performed routinely for longer follow- ups, particularly in patients who were treated as young children. (orig.)

  17. Important factors for cell-membrane permeabilization by gold nanoparticles activated by nanosecond-laser irradiation

    Directory of Open Access Journals (Sweden)

    Yao CP

    2017-08-01

    Full Text Available Cuiping Yao,1,2,* Florian Rudnitzki,2,* Gereon Hüttmann,2,3 Zhenxi Zhang,1 Ramtin Rahmanzadeh2 1Key Laboratory of Biomedical Information Engineering of Education Ministry, Institute of Biomedical Analytical Technology and Instrumentation, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, China; 2Institute of Biomedical Optics, University of Lübeck, Lübeck, 3Airway Research Center North (ARCN, Member of the German Center for Lung Research (DZL, Kiel, Germany *These authors contributed equally to this work Purpose: Pulsed-laser irradiation of light-absorbing gold nanoparticles (AuNPs attached to cells transiently increases cell membrane permeability for targeted molecule delivery. Here, we targeted EGFR on the ovarian carcinoma cell line OVCAR-3 with AuNPs. In order to optimize membrane permeability and to demonstrate molecule delivery into adherent OVCAR-3 cells, we systematically investigated different experimental conditions. Materials and methods: AuNPs (30 nm were functionalized by conjugation of the antibody cetuximab against EGFR. Selective binding of the particles was demonstrated by silver staining, multiphoton imaging, and fluorescence-lifetime imaging. After laser irradiation, membrane permeability of OVCAR-3 cells was studied under different conditions of AuNP concentration, cell-incubation medium, and cell–AuNP incubation time. Membrane permeability and cell viability were evaluated by flow cytometry, measuring propidium iodide and fluorescein isothiocyanate–dextran uptake. Results: Adherently growing OVCAR-3 cells can be effectively targeted with EGFR-AuNP. Laser irradiation led to successful permeabilization, and 150 kDa dextran was successfully delivered into cells with about 70% efficiency. Conclusion: Antibody-targeted and laser-irradiated AuNPs can be used to deliver molecules into adherent cells. Efficacy depends not only on laser parameters but also on AuNP:cell ratio, cell-incubation medium

  18. Exposure to nerve growth factor worsens nephrotoxic effect induced by Cyclosporine A in HK-2 cells.

    Directory of Open Access Journals (Sweden)

    Donatella Vizza

    Full Text Available Nerve growth factor is a neurotrophin that promotes cell growth, differentiation, survival and death through two different receptors: TrkA(NTR and p75(NTR. Nerve growth factor serum concentrations increase during many inflammatory and autoimmune diseases, glomerulonephritis, chronic kidney disease, end-stage renal disease and, particularly, in renal transplant. Considering that nerve growth factor exerts beneficial effects in the treatment of major central and peripheral neurodegenerative diseases, skin and corneal ulcers, we asked whether nerve growth factor could also exert a role in Cyclosporine A-induced graft nephrotoxicity. Our hypothesis was raised from basic evidence indicating that Cyclosporine A-inhibition of calcineurin-NFAT pathway increases nerve growth factor expression levels. Therefore, we investigated the involvement of nerve growth factor and its receptors in the damage exerted by Cyclosporine A in tubular renal cells, HK-2. Our results showed that in HK-2 cells combined treatment with Cyclosporine A + nerve growth factor induced a significant reduction in cell vitality concomitant with a down-regulation of Cyclin D1 and up-regulation of p21 levels respect to cells treated with Cyclosporine A alone. Moreover functional experiments showed that the co-treatment significantly up-regulated human p21promoter activity by involvement of the Sp1 transcription factor, whose nuclear content was negatively regulated by activated NFATc1. In addition we observed that the combined exposure to Cyclosporine A + nerve growth factor promoted an up-regulation of p75 (NTR and its target genes, p53 and BAD leading to the activation of intrinsic apoptosis. Finally, the chemical inhibition of p75(NTR down-regulated the intrinsic apoptotic signal. We describe two new mechanisms by which nerve growth factor promotes growth arrest and apoptosis in tubular renal cells exposed to Cyclosporine A.

  19. Food irradiation

    International Nuclear Information System (INIS)

    Matsuyama, Akira

    1990-01-01

    This paper reviews researches, commentaries, and conference and public records of food irradiation, published mainly during the period 1987-1989, focusing on the current conditions of food irradiation that may pose not only scientific or technologic problems but also political issues or consumerism. Approximately 50 kinds of food, although not enough to fill economic benefit, are now permitted for food irradiation in the world. Consumerism is pointed out as the major factor that precludes the feasibility of food irradiation in the world. In the United States, irradiation is feasible only for spices. Food irradiation has already been feasible in France, Hollands, Belgium, and the Soviet Union; has under consideration in the Great Britain, and has been rejected in the West Germany. Although the feasibility of food irradiation is projected to increase gradually in the future, commercial success or failure depends on the final selection of consumers. In this respect, the role of education and public information are stressed. Meat radicidation and recent progress in the method for detecting irradiated food are referred to. (N.K.) 128 refs

  20. Mutation induction in haploid yeast after split-dose radiation-exposure. I. Fractionated UV-irradiation.

    Science.gov (United States)

    Schenk, K; Zölzer, F; Kiefer, J

    1989-01-01

    Mutation induction was investigated in wild-type haploid yeast Saccharomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency.

  1. Biological significance of the focus on DNA damage checkpoint factors remained after irradiation of ionizing radiation

    International Nuclear Information System (INIS)

    Yamauchi, Motohiro; Suzuki, Keiji

    2005-01-01

    This paper reviews recent reports on the focus formation and participation to checkpoint of (such phosphorylated (P-d) as below) ATM and H2AX, MDC1, 53BP1 and NBS1, and discusses their role in DNA damage checkpoint induction mainly around authors' studies. When the cell is irradiated by ionizing radiation, the subtype histone like H2AX is P-d and the formed focus', seen in the nucleus on immuno-fluorographic observation, represents the P-d H2AX at the damaged site of DNA. The role of P-d ATM (the product of causative gene of ataxia-telangiectasia mutation, a protein kinase) has been first shown by laser beam irradiation. Described are discussions on the roles and functions after irradiation in focus formation and DNA damage checkpoint of P-d H2AX (a specific histone product by the radiation like γ-ray as above), P-d ATM, MDC1 (a mediator of DNA damage check point protein 1), 53BP1, (a p53 binding protein) and NBS1 (the product of the causative gene of Nijmegen Breakage Syndrome). Authors have come to point out the remained focal size increase as implications of the efficient repair of damaged DNA, and the second cycled p53 accumulation, of tumor suppression. Thus evaluation of biological significance of these aspects, scarcely noted hitherto, is concluded important. (S.I.)

  2. Capability demonstration of simultaneous proton beam irradiation during exposure to molten lead–bismuth eutectic for HT9 steel

    International Nuclear Information System (INIS)

    Qvist, Staffan; Bolind, Alan Michael; Hosemann, Peter; Wang, Yongqiang; Tesmer, Joseph; De Caro, Magdalena Serrano; Bourke, Mark

    2013-01-01

    We report the design and assembly of a corrosion station to enable simultaneous proton irradiation of a metallic surface that was also in contact with molten lead–bismuth eutectic (LBE). The capability has been established at the ion beam materials laboratory at Los Alamos National Laboratory (LANL). The engineering design focused on temperature and oxygen content control in the LBE, as well as the ability to achieve doses significantly in excess of 1 dpa in the contact region over the irradiation campaigns. In the preliminary demonstration of capability reported here, a sample made of HT9 steel was placed in contact with LBE at 450 °C and irradiated for 58 h at an average proton beam current of 0.3 μA/mm 2 . SRIM [1] calculations indicate that the nominal surface dose ranged from approximately 3–22 dpa. This paper outlines the experimental setup and design constraints. Characterization of the sample will be reported in a subsequent paper.

  3. Capability demonstration of simultaneous proton beam irradiation during exposure to molten lead–bismuth eutectic for HT9 steel

    Energy Technology Data Exchange (ETDEWEB)

    Qvist, Staffan, E-mail: staffan@berkeley.edu [University of California, Berkeley (United States); Bolind, Alan Michael [University of California, Berkeley (United States); Japan Atomic Energy Agency (Japan); Hosemann, Peter [University of California, Berkeley (United States); Wang, Yongqiang; Tesmer, Joseph; De Caro, Magdalena Serrano; Bourke, Mark [Los Alamos National Laboratory (United States)

    2013-01-11

    We report the design and assembly of a corrosion station to enable simultaneous proton irradiation of a metallic surface that was also in contact with molten lead–bismuth eutectic (LBE). The capability has been established at the ion beam materials laboratory at Los Alamos National Laboratory (LANL). The engineering design focused on temperature and oxygen content control in the LBE, as well as the ability to achieve doses significantly in excess of 1 dpa in the contact region over the irradiation campaigns. In the preliminary demonstration of capability reported here, a sample made of HT9 steel was placed in contact with LBE at 450 °C and irradiated for 58 h at an average proton beam current of 0.3 μA/mm{sup 2}. SRIM [1] calculations indicate that the nominal surface dose ranged from approximately 3–22 dpa. This paper outlines the experimental setup and design constraints. Characterization of the sample will be reported in a subsequent paper.

  4. Time factors in breast carcinoma; Influence of delay between external irradiation and brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dubray, B; Thames, H D [Anderson (M.D.) Hospital and Tumor Inst., Houston, TX (United States); Mazeron, J J; Simon, J M; Pechoux, C le; Calitchi, E; Otmezguine, Y; Bourgeois, J.P. le; Pierquin, B [Hopital Henri-Mondor, 94 - Creteil (France)

    1992-12-01

    From 1971-1983, 398 biopsy-proven breast adenocarcinomas (33 T[sub 1], 309 T[sub 2], 56 T[sub 3]) were treated conservatively at Hopital Henri Mondor by an initial course of external irradiation (45 Gy, 25 fractions, 5 weeks) followed by interstitial iridium-192 implant for a further 37 Gy to the tumor. The mean interval between external irradiation and brachytherapy was 5.9 weeks (S.D. 1.7, range 1-18). 77 local failures were observed at 10-148 months (median 34.5). The actuarial probabilities (S.E.) of local control at 5 and 10 years were 0.86 (0.02) and 0.74 (0.03) respectively. The follow-up for patients free of local recurrence was 4-205 months (median 95). Multivariate analysis showed an increasing probability of local failure with longer interval between external irradiation and brachytherapy (Relative Risk [RR] 1.23 [95% confidence limits: 1.07, 1.41] per week, p=0.005), and a lower risk of failure in case of complete tumor regression after external irradiation (RR 0.47 [0.25, 0.90], p=0.22), and higher brachytherapy dose rate (RR 0.13 [0.02 , 1.02] per Gy/h, p=0.053). No influence of tumor size and total dose (possibly because only limited variations in total dose were observed), or histological grading (not performed in 140 [35%] patients) was found. Because of the lack of dose-control relationship, quantification of the effects of delay between external irradiation and brachytherapy (in terms of compensatory dose) and of dose rate (Incomplete Repair Model) was not possible. The present analysis suggests that the implant dose rate should be high (but no extrapolation can be made above 1 Gy/h) or that total dose should be increased to compensate lower dose rate. However, data do not indicate how much extra dose is necessary, since no dose-control relationship was elicited. In addition, the treatment duration should remain as short as possible in order to maximize local control. (author). 23 refs., 2 figs., 3 tabs.

  5. Environmental Factors Affecting Asthma and Allergies: Predicting and Simulating Downwind Exposure to Airborne Pollen

    Science.gov (United States)

    Luvall, Jeffrey; Estes, Sue; Sprigg, William A.; Nickovic, Slobodan; Huete, Alfredo; Solano, Ramon; Ratana, Piyachat; Jiang, Zhangyan; Flowers, Len; Zelicoff, Alan

    2009-01-01

    This slide presentation reviews the environmental factors that affect asthma and allergies and work to predict and simulate the downwind exposure to airborne pollen. Using a modification of Dust REgional Atmosphere Model (DREAM) that incorporates phenology (i.e. PREAM) the aim was to predict concentrations of pollen in time and space. The strategy for using the model to simulate downwind pollen dispersal, and evaluate the results. Using MODerate-resolution Imaging Spectroradiometer (MODIS), to get seasonal sampling of Juniper, the pollen chosen for the study, land cover on a near daily basis. The results of the model are reviewed.

  6. Skin barrier integrity and natural moisturising factor levels after cumulative dermal exposure to alkaline agents in atopic dermatitis

    NARCIS (Netherlands)

    Angelova-Fischer, Irena; Dapic, Irena; Hoek, Anne-Karin; Jakasa, Ivone; Fischer, Tobias W.; Zillikens, Detlef; Kezic, Sanja

    2014-01-01

    Dermal exposure to alkaline agents may lead to skin barrier damage and irritant contact dermatitis. The objective of this study was to investigate the effects of cumulative exposure to 0.5% sodium lauryl sulphate (SLS) and 0.15% NaOH on the barrier function and natural moisturising factor (NMF)

  7. Interaction between x-irradiated plateau-phase bone marrow stromal cell lines and co-cultivated factor-dependent cell lines leading to leukemogenesis in vitro

    International Nuclear Information System (INIS)

    Naparstek, E.; Anklesaria, P.; FitzGerald, T.J.; Sakakeeny, M.A.; Greenberger, J.S.

    1987-01-01

    Plateau-phase mouse clonal bone marrow stromal cell lines D2XRII and C3H cl 11 produce decreasing levels of M-CSF (CSF-1), a specific macrophage progenitor cell humoral regulator, following X-irradiation in vitro. The decrease did not go below 40% of control levels, even after irradiation doses of 50,000 rad (500 Gy). In contrast, a distinct humoral regulator stimulating growth of GM-CSF/IL-3 factor-dependent (FD) hematopoietic progenitor cell lines was detected following radiation to doses above 2000 rad. This humoral factor was not detectable in conditioned medium from irradiated cells, weakly detected using factor-dependent target cell populations in agar overlay, and was prominently detected by liquid co-cultivation of factor-dependent cells with irradiated stromal cell cultures. Subclonal lines of FD cells, derived after co-cultivation revealed karyotypic abnormalities and induced myeloblastic tumors in syngeneic mice. Five-eight weeks co-cultivation was required for induction of factor independence and malignancy and was associated with dense cell to cell contact between FD cells and stromal cells demonstrated by light and electron microscopy. Increases in hematopoietic to stromal cell surface area, total number of adherent cells per flask, total non-adherent cell colonies per flask, and cumulative non-adherent cell production were observed after irradiation. The present data may prove very relevant to an understanding of the cell to cell interactions during X-irradiation-induced leukemia

  8. Early Childhood Risk Factors for Mealtime TV Exposure and Engagement in Low-Income Families.

    Science.gov (United States)

    Domoff, Sarah E; Lumeng, Julie C; Kaciroti, Niko; Miller, Alison L

    To identify whether child and mother characteristics in early childhood predict TV exposure and engagement during mealtime in middle childhood. A total of 220 low-income mother-child dyads participated. Children were 4.26 years old (SD = 0.51) at baseline and 5.94 years (SD = 0.68) at 2-year follow-up. Mothers completed baseline measures of child negative emotionality and parenting practices. Family mealtimes were video recorded and coded for background TV exposure and child TV engagement. Multinomial logistic regression tested whether child emotionality and parenting practices during early childhood predicted risk of child TV exposure or engagement during mealtime, relative to no TV use, 2 years later. Children with greater negative emotionality in early childhood were more likely to engage with TV during mealtime than to have no TV. Similarly, early parenting disciplinary practices characterized by over-reactivity and laxness increased the risk for child TV engagement versus no TV during mealtime approximately 2 years later. We identified 2 factors that associated with an increased risk for TV viewing during meals. Helping parents manage child negative emotionality using positive parenting strategies might reduce later child TV engagement and improve the quality of family mealtimes. Copyright © 2016 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  9. Occupational Exposure to Mineral Turpentine and Heavy Fuels: A Possible Risk Factor for Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Rafik Helou

    2014-06-01

    Full Text Available Background: The association between solvents and Alzheimer's disease (AD has been the subject of several studies. Yet, only few studies have examined the various solvents separately, and the controls have rarely been monitored long enough. For these reasons and others, we believe that further studies are required. Objectives: The objective of this study was to identify solvents associated with the clinicoradiological diagnostic of AD or mixed-type dementia (MD. Methods: A retrospective case-control study was performed in 156 patients followed up at the Memory Diagnostic Center of Bertinot Juel Hospital (France. The inclusion criteria were known occupation(s, a Mini-Mental State Examination (MMSE score ≥10 at the first visit, a neuropsychological evaluation performed and a diagnosis established in our Memory Diagnostic Center. The diagnostics were crossed with 9 solvents belonging to two classes of solvents. Exposure was evaluated using French national job-exposure matrices. Results: Certain petroleum-based solvents and fuels (i.e. mineral turpentine, diesel fuel, fuel oil and kerosene were associated with a diagnosis of AD or MD. This association was still significant after adjustment for age, sex and education (adjusted OR: 6.5; 95% CI: 2-20. Conclusion: Occupational exposure to mineral turpentine and heavy fuels may be a risk factor for AD and MD.

  10. Work procedures and risk factors for high rdiation exposure among radiologic technologists in South Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Young; Choi, Yeong Chull [Dept. of Preventive Medicine, Keimyung University College of Medicine, Daegu (Korea, Republic of); Lee, Won Jin; Cha, Eun Shil [Dept. of Preventive Medicine, Korea University College of Medicine, Seoul (Korea, Republic of)

    2016-12-15

    Radiologic technologists currently consist of 31.5% among diagnostic radiation workers in South Korea. Among diagnostic radiation workers, radiologic technologists receive the highest annual and collective doses in South Korea. Comprehensive assessment of the work practices and associated radiation doses from diagnostic radiology procedures should be undertaken for effective prevention for radiologic technologists. Using the national survey, this study aimed (1) to explore the distribution of the work procedures performed by gender, (2) to evaluate occupational radiation exposure by work characteristics and safety compliance, (3) to identify the primary factors influencing high radiation exposure among radiologic technologists in South Korea. This study provided detailed information on work practices, number of procedures performed on weekly basis, and occupational radiation doses among radiologic technologists in South Korea. Average radiation dose for radiologic technologists is higher than other countries, and type of facility, work safety, and wearing lead apron explained quite a portion of increased risk in the association between radiology procedures and radiation exposure among radiologic technologists.

  11. Work procedures and risk factors for high rdiation exposure among radiologic technologists in South Korea

    International Nuclear Information System (INIS)

    Kim, Jae Young; Choi, Yeong Chull; Lee, Won Jin; Cha, Eun Shil

    2016-01-01

    Radiologic technologists currently consist of 31.5% among diagnostic radiation workers in South Korea. Among diagnostic radiation workers, radiologic technologists receive the highest annual and collective doses in South Korea. Comprehensive assessment of the work practices and associated radiation doses from diagnostic radiology procedures should be undertaken for effective prevention for radiologic technologists. Using the national survey, this study aimed (1) to explore the distribution of the work procedures performed by gender, (2) to evaluate occupational radiation exposure by work characteristics and safety compliance, (3) to identify the primary factors influencing high radiation exposure among radiologic technologists in South Korea. This study provided detailed information on work practices, number of procedures performed on weekly basis, and occupational radiation doses among radiologic technologists in South Korea. Average radiation dose for radiologic technologists is higher than other countries, and type of facility, work safety, and wearing lead apron explained quite a portion of increased risk in the association between radiology procedures and radiation exposure among radiologic technologists.

  12. Determination of correction and conversion factor of exposure rate generated Gamma spectrometer GR-320 to Victoreen data

    International Nuclear Information System (INIS)

    Supardjo-AS; Mappa, Djody-Rachim; Nasrun-Syamsul; Syamsul-Hadi

    2000-01-01

    Exposure rate data of Muria Peninsula were generated from Victoreen-491 measurement and calculation of radioelement content in soil which were measured by Exploranium GR-320, using IAEA formula. However those data are not be comparable so the exposure rate calculated from Gamma Spectrometer data necessarily to be corrected. The correction factor was determinate by measuring the exposure rate of at the NMDC's back yard selected location using Victoreen-491 and Gamma Spectrometer Exploranium GR-320 . Correction factor was created by comparing mean exposure rate data that calculated from 30 data measured by Gamma Spectrometer instrument and to those Victoreen's exposure rate. Conversion factor was gained from comparing of total count data of Gamma Spectrometer Exploranium GR-320 to Victoreen's exposure rate data. The correction factor of Exploranium GR-320's exposure rate is 0.34 μR/hours, and the conversion factor of total count is 0.0092 μR/hours per c/m. Deviation Victoreen 491 = 4.7 % and Gamma Spectrometer Exploranium GR-320 8.6 %

  13. The association between exposure to psychosocial work factors and mental health in older employees, a 3-year follow-up study

    NARCIS (Netherlands)

    Havermans, B.M.; Boot, C.R.L.; Hoekstra, T.; Houtman, I.L.D.; Brouwers, E.P.M.; Anema, J.R.; Beek, A.J. van der

    2018-01-01

    Purpose Unfavourable exposure to psychosocial work factors threatens older employees’ mental health, and their sustained employment. This study assesses whether an improved compared to stable unfavourable and stable favourable exposure to psychosocial work factors is associated with a change in

  14. The association between exposure to psychosocial work factors and mental health in older employees : A 3-year follow-up study

    NARCIS (Netherlands)

    Havermans, B.M.; Boot, C.R.L.; Hoekstra, T.; Houtman, I.L.D.; Brouwers, E.P.M.; Anema, J.R.; Van Der Beek, A.J.

    2018-01-01

    Purpose Unfavourable exposure to psychosocial work factors threatens older employees' mental health, and their sustained employment. This study assesses whether an improved compared to stable unfavourable and stable favourable exposure to psychosocial work factors is associated with a change in

  15. Exposure to suicidal behaviors: A common suicide risk factor or a personal negative life event?

    Science.gov (United States)

    Harris, Keith M; Bettiol, Silvana

    2017-02-01

    Numerous suicide risk factors have been proposed but not adequately validated for epidemiology, treatment and prevention efforts. Exposures to suicidal behaviors (ESB), from family and friend suicide attempts and completions, were tested for validity as a suicidal risk factor and also for measurement and construct adequacy. An anonymous online survey yielded 713 participants (aged 18-71), who reported ESB, completed the Suicidal Affect-Behavior-Cognition Scale (SABCS), and comprised a broad spectrum on those variables. Tests of dimensionality and internal consistency showed the four ESB variables (attempts/completions through family/friends) were independent and did not form a common factor or an identifiable ESB latent trait. ESB variables were, however, associated with demographic and psychiatric histories. A battery of tests revealed no meaningful associations between ESB and total suicidality or suicide risk factors (social support, depression, anxiety, stress, satisfaction with life and emotional stability). In addition, in contrast to previous reports, young adults ( n = 200; aged 18-20) showed no increased suicidality due to ESB. Results showed no validity for ESB as a common risk factor for suicidality or other psychopathology, or as a latent trait. ESB showed evidence as a personal negative life event with individual effects and interpretations.

  16. Prenatal exposure to lead in Spain: Cord blood levels and associated factors

    Energy Technology Data Exchange (ETDEWEB)

    Llop, Sabrina, E-mail: llop_sab@gva.es [Centre of Public Health Research (CSISP), Av Catalunya 21, 46020, Valencia (Spain); Carlos III Health Institute (ISCIII), 20220 Majadahonda, Madrid (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Aguinagalde, Xabier [Public Health Laboratory of Alava, Direccion de Salud Publica, Gobierno Vasco, Santiago 11, 01002, Vitoria-Gasteiz, Basque Country (Spain); Vioque, Jesus [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Universidad Miguel Hernandez, Av de Alicante KM 87, 03550, Sant Joan d' Alacant (Spain); Ibarluzea, Jesus [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Departamento de Sanidad Gobierno Vasco, Subdireccion de Salud Publica de Gipuzkoa, Avenida de Navarra 4, 20013 San Sebastian (Spain); Biodonostia, Instituto de Investigacion Biomedica, San Sebastian (Spain); Guxens, Monica [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); Casas, Maribel [Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); Murcia, Mario [Centre of Public Health Research (CSISP), Av Catalunya 21, 46020, Valencia (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Ruiz, Maria [Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); and others

    2011-05-01

    Introduction and Objective: Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). Methods: A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. {>=} vs < 2 {mu}g/dL). Results: A low percentage of cord blood samples with lead levels {>=} 2 {mu}g/dL were found (5.9%). Geometric mean and maximum were 1.06 {mu}g/dL and 19 {mu}g/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels {>=} 2 {mu}g/dL. Conclusion: In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. - Research Highlights: {yields} Pb is a ubiquitous environmental pollutant with harmful effects on neurodevelopment. {yields} Cord blood Pb levels in

  17. Prenatal exposure to lead in Spain: Cord blood levels and associated factors

    International Nuclear Information System (INIS)

    Llop, Sabrina; Aguinagalde, Xabier; Vioque, Jesus; Ibarluzea, Jesus; Guxens, Monica; Casas, Maribel; Murcia, Mario; Ruiz, Maria

    2011-01-01

    Introduction and Objective: Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). Methods: A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. ≥ vs < 2 μg/dL). Results: A low percentage of cord blood samples with lead levels ≥ 2 μg/dL were found (5.9%). Geometric mean and maximum were 1.06 μg/dL and 19 μg/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels ≥ 2 μg/dL. Conclusion: In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. - Research Highlights: → Pb is a ubiquitous environmental pollutant with harmful effects on neurodevelopment. → Cord blood Pb levels in Spanish newborn are low in

  18. Gamma-ray energy absorption and exposure buildup factor studies in some human tissues with endometriosis

    Energy Technology Data Exchange (ETDEWEB)

    Kurudirek, Murat, E-mail: mkurudirek@gmail.co [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey); Dogan, Bekir [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey); Ingec, Metin [Faculty of Medicine, Department of Obstetrics and Gynecology, Ataturk University, 25240 Erzurum (Turkey); Ekinci, Neslihan; Ozdemir, Yueksel [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey)

    2011-02-15

    Human tissues with endometriosis have been analyzed in terms of energy absorption (EABF) and exposure (EBF) buildup factors using the five-parameter geometric progression (G-P) fitting formula in the energy region 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path). Chemical compositions of the tissue samples were determined using a wavelength dispersive X-ray fluorescence spectrometer (WDXRFS). Possible conclusions were drawn due to significant variations in EABF and EBF for the selected tissues when photon energy, penetration depth and chemical composition changed. Buildup factors so obtained may be of use when the method of choice for treatment of endometriosis is radiotherapy.

  19. Anti-Inflammatory Effect of ETAS®50 by Inhibiting Nuclear Factor-κB p65 Nuclear Import in Ultraviolet-B-Irradiated Normal Human Dermal Fibroblasts

    Directory of Open Access Journals (Sweden)

    Ken Shirato

    2018-01-01

    Full Text Available Ultraviolet (UV irradiation induces proinflammatory responses in skin cells, including dermal fibroblasts, accelerating premature skin aging (photoaging. ETAS 50, a standardized extract from the Asparagus officinalis stem, is a novel and unique functional food that suppresses proinflammatory responses of hydrogen peroxide-stimulated skin fibroblasts and interleukin- (IL- 1β-stimulated hepatocytes. To elucidate its antiphotoaging potencies, we examined whether ETAS 50 treatment after UV-B irradiation attenuates proinflammatory responses of normal human dermal fibroblasts (NHDFs. UV-B-irradiated NHDFs showed reduced levels of the cytosolic inhibitor of nuclear factor-κB α (IκBα protein and increased levels of nuclear p65 protein. The nuclear factor-κB nuclear translocation inhibitor JSH-23 abolished UV-B irradiation-induced IL-1β mRNA expression, indicating that p65 regulates transcriptional induction. ETAS 50 also markedly suppressed UV-B irradiation-induced increases in IL-1β mRNA levels. Immunofluorescence analysis revealed that ETAS 50 retained p65 in the cytosol after UV-B irradiation. Western blotting also showed that ETAS 50 suppressed the UV-B irradiation-induced increases in nuclear p65 protein. Moreover, ETAS 50 clearly suppressed UV-B irradiation-induced distribution of importin-α protein levels in the nucleus without recovering cytosolic IκBα protein levels. These results suggest that ETAS 50 exerts anti-inflammatory effects on UV-B-irradiated NHDFs by suppressing the nuclear import machinery of p65. Therefore, ETAS 50 may prevent photoaging by suppressing UV irradiation-induced proinflammatory responses of dermal fibroblasts.

  20. Influence on DNA repair inhibitors on dominant lethal factors after gamma irradiation

    International Nuclear Information System (INIS)

    Engl, D.

    1978-01-01

    Experiments were performed in order to test the hypothesis of a correlation between ionizing radiation and DNA repair inhibition under in vivo conditions. In a biometrically planned dominant lethal test on mice, the repair inhibition on the male gametes by butazolidine, TWEEN 80 and vitamin A was studied after gamma irradiation at 20 rad/10 min. No effect was observed in the case of butazolidine and TWEEN 80, whereas the influence of a high concentration of vitamin A (1 million IE/kg) was just at the statistical significancy threshold. (G.G.)

  1. Occupational exposure to ionizing radiation as a risk factor for free-radicals mediated diseases

    International Nuclear Information System (INIS)

    Djurovic, B.; Spasic-Jokic, V.; Selakovic, V.

    2007-01-01

    Complete text of publication follows. It was experimentally showed, that the exposure to low doses of ionizing radiation (IR) result in over-production of oxygen derived free radicals with inverse dose-rate effect. The oxidative stress that follows, especially cell membrane damage, was considered by Petkau, as crucial step in the induction of radiation injuries. From clinical research and practice with other unexposed patients is known that this type of cell damage can lead to an impairment of cellular function and can cause many free-radicals mediated diseases, such as atherosclerosis, damage of heart muscles, inflammatory and immuno-reactive lesions, senile dementia, cancer, etc. The aim of this paper is to investigate if occupational exposure to low doses of IR change the redox status of exposed personnel, and if so, is it the additional risk factor for free-radicals mediated diseases. Subjects: 77 medical workers, devided in two groups: 44 occupationally exposed to ionizing radiation (E), and 33 controls (C), matched in age, gender, habits-daitary, alcohol consumption, smoking and exposure time, were examined. Methods: Radiation dose accumulated over years was calculated on the basis of individual TL-dose records. Superoxide-anion and MDA production, as well as SOD (MnSOD, CuZnSOD) and GSH activity were determined in blood samples spectrophotometrically. Results: Significantly higher incidence of cataract, and higher, but not significant, incidence of cardiovascular diseases was noticed in exposed. Our results also confirmed significantly higher superoxide and MDA production (p=0.0049, 0.000028, respectively), as well as, increased activity of MnSOD and CuZnSOD (p0.0105, 0.001, respectively), and decreased level of GSH (p=0.0599) in exposed. Conclusions: Our results showed that low doses of IR could induce oxidative stress and for that reason could be considered as additional risk factor for free radical-mediated diseases. Further epidemiological studies are

  2. Recurrent exposure to nicotine differentiates human bronchial epithelial cells via epidermal growth factor receptor activation

    International Nuclear Information System (INIS)

    Martinez-Garcia, Eva; Irigoyen, Marta; Anso, Elena; Martinez-Irujo, Juan Jose; Rouzaut, Ana

    2008-01-01

    Cigarette smoking is the major preventable cause of lung cancer in developed countries. Nicotine (3-(1-methyl-2-pyrrolidinyl)-pyridine) is one of the major alkaloids present in tobacco. Besides its addictive properties, its effects have been described in panoply of cell types. In fact, recent studies have shown that nicotine behaves as a tumor promoter in transformed epithelial cells. This research focuses on the effects of acute repetitive nicotine exposure on normal human bronchial epithelial cells (NHBE cells). Here we show that treatment of NHBE cells with recurrent doses of nicotine up to 500 μM triggered cell differentiation towards a neuronal-like phenotype: cells emitted filopodia and expressed neuronal markers such as neuronal cell adhesion molecule, neurofilament-M and the transcription factors neuronal N and Pax-3. We also demonstrate that nicotine treatment induced NF-kB translocation to the nucleus, phosphorylation of the epidermal growth factor receptor (EGFR), and accumulation of heparin binding-EGF in the extracellular medium. Moreover, addition of AG1478, an inhibitor of EGFR tyrosine phosphorylation, or cetuximab, a monoclonal antibody that precludes ligand binding to the same receptor, prevented cell differentiation by nicotine. Lastly, we show that differentiated cells increased their adhesion to the extracellular matrix and their protease activity. Given that several lung pathologies are strongly related to tobacco consumption, these results may help to better understand the damaging consequences of nicotine exposure

  3. The effects of air pollution and climatic factors on atmospheric corrosion of marble under field exposure

    International Nuclear Information System (INIS)

    Lan, Tran Thi Ngoc; Nishimura, Rokuro; Tsujino, Yoshio; Satoh, Yukihiro; Thi Phuong Thoa, Nguyen; Yokoi, Masayuki; Maeda, Yasuaki

    2005-01-01

    The atmospheric corrosion of marble was evaluated in terms of SO 2 concentration as air pollution and climatic factors such as rainfall, relative humidity, temperature and so on under the field exposure. Marble of calcite type (CaCO 3 ) was exposed to outdoor atmospheric environment with and without a rain shelter at four test sites in the southern part of Vietnam for 3-month, 1- and 2-year periods from July 2001 to September 2003. The thickness loss of marble was investigated gravimetrically. X-ray diffraction and X-ray fluorescent methods were applied to study corrosion products on marble. The corrosion product of marble was only gypsum (CaSO 4 . 2H 2 O) and was washed out by rain under the unsheltered exposure condition. It was found that the most substantial factors influencing the corrosion of marble were rainfall, SO 2 concentration in the air and relative humidity. Based on the results obtained, we estimated the dose-response functions for the atmospheric corrosion of marble in the southern part of Vietnam

  4. Influence of the irradiation by the {gamma} rays on various factors of immunity; Influence de l'irradiation par les rayons {gamma} sur divers facteurs d'immunite

    Energy Technology Data Exchange (ETDEWEB)

    Gaude, G; Coursaget, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    Exposed animals often present, in the days or weeks following the irradiation, heavy infectious lesions. The goal of this survey was to search the influence of the total irradiation by the gamma radiation from cobalt-60, on the organism, on the phagocytic power of the leukocytes and on the biogenesis of antibodies. The experiences were done on hundred animals, rabbits and guinea pigs. All irradiations have been achieved with eight sources of Cobalt 60 of 10 curies each, disposed on a sphere of 1 m, the animal living the region neighboring of the center. The intensity of the radiation, in these conditions, is about 100 roentgens per hour. (authors) [French] Les animaux irradies presentent souvent, dans les jours ou les semaines qui suivent l'irradiation, de graves lesions infectieuses. Le but de cette etude etait de rechercher l'influence de l'irradiation totale de l'organisme par le rayonnement gamma du cobalt 60 sur le pouvoir phagocytaire des leucocytes et sur la biogenese des anticorps. Les experiences portent sur une centaine d'animaux, lapins et cobayes. Toutes les irradiations ont ete realisees avec huit sources de Cobalt 60 de 10 curies chacune, disposees sur une sphere de 1 m de rayon, les animaux ocoupant la region voisine du centre. L'intensite du rayonnement est, dans ces conditions, d'environ 100 roentgens par heure. (auteurs)

  5. Measuring lifetime stress exposure and protective factors in life course research on racial inequality and birth outcomes.

    Science.gov (United States)

    Malat, Jennifer; Jacquez, Farrah; Slavich, George M

    2017-07-01

    There has been a long-standing interest in better understanding how social factors contribute to racial disparities in health, including birth outcomes. A recent emphasis in this context has been on identifying the effects of stress exposure and protective factors experienced over the entire lifetime. Yet despite repeated calls for a life course approach to research on this topic, very few studies have actually assessed how stressors and protective factors occurring over women's lives relate to birth outcomes. We discuss this issue here by describing how challenges in the measurement of lifetime stress exposure and protective factors have prevented researchers from developing an empirically-based life course perspective on health. First, we summarize prevailing views on racial inequality and birth outcomes; second, we discuss measurement challenges that exist in this context; and finally, we describe both new tools and needed tools for assessing lifetime stress exposure and suggest opportunities for integrating information on stress exposure and psychosocial protective factors. We conclude that more studies are needed that integrate information about lifetime stress exposures and the protective factors that promote resilience against such exposures to inform policy and practice recommendations to reduce racial disparities in birth outcomes.

  6. Effects of non-implantation factors on survival rate of microbe irradiated by low-energy N+

    International Nuclear Information System (INIS)

    Yang Tianyou; Chen Linhai; Qin Guangyong; Li Zongwei; Su Mingjie; Wang Yanping; Chang Shenghe; Huo Yuping; Li Zongyi

    2006-01-01

    The effects of non-implantation factors, such as drying, vacuum and the staying time of the E.coli LE392 culture, on survival rate of E.coli LE392 were studied when E.coli LE392 was irradiated by the low-energy N + . The results show that the survival rate of E.coli LE392 does not reduce steadily all the time but rapidly drops sometime during drying. The survival rate of E.coli LE392 declines sharply as the samples are placed in vacuum, then falls in distinctively with increasing of time. the tolerance of E.coli LE392 towards vacuum increasingly strengthens when the E.coli LE392 culture is placed at room temperature. Preparing the culture in batchs can ensure the consistency of the irradiated samples and avoid errors caused by the inconsistent samples. When the non-implantation factors are controlled, E.coli is implanted by 30 kev N + of 1 x 10 14 cm -2 and 3 x 10 15 cm -2 , respectively. And the results show no difference in the E.coli's survival rates between batchs at the same dose. (authors)

  7. [Effects of intermittent hypoxic exposure on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha and erythropoietin levels].

    Science.gov (United States)

    Zhang, Cheng-yan; Zhang, Ji-xin; Lü, Xiao-tao; Li, Bao-yu

    2009-10-01

    To investigate the effects of intermittent hypoxic exposure and normoxic convalescence on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha (HIF-1alpha) and erythropoietin (EPO) levels. Rat models of intermittent hypoxic exposure were established, combined with the clinical research on volunteers experiencing the intermittent plateau work. Blood samples for red blood cell (RBC) counts, hemoglobin (Hb) and hematocrit (HCT) were collected, serum HIF-1alpha and EPO levels were measured using enzyme linked immunosorbent assay. RBC counts, Hb concentration and HCT were significantly higher than the normoxic group (P hypoxic exposure can enhance serum hypoxia inducible factor-1 alpha and erythropointin levels and the generation of red blood cells, which leads to an increase in hemoglobin concentration and hematocrit. The results have changed with the hypoxic exposure period prolonged. Normoxic convalescence after intermittent hypoxic exposure can make the related indexes reduced, and contribute to the organism recovery.

  8. [Current status of hearing loss and related influencing factors in workers with noise exposure in refining and chemical industry].

    Science.gov (United States)

    Wu, S S; Yu, J N; He, C H; Mu, H X; Wang, C; Zhang, Y; Zhang, C Y; Yu, S F; Li, X L

    2016-12-20

    Objective: To investigate the current status of hearing loss and related influencing factors in workers with noise exposure in refining and chemical industry. Methods: From August 2015 to March 2016, the investigation method of collecting the data of past occupational health examinations and measuring noise in working environment was used to enroll 8 672 male workers. Results: Of all workers, 11.6% were diagnosed with hearing loss. There were significant differences in the distribution of hearing impairment among workers exposed to noise at different ages, device types and types of work (χ(2)=17.80, 77.80 and 30.53, all P hearing loss in workers with noise exposure in refining and chemical industry. Conclusion: The level of noise exposure and working years with noise exposure are main influencing factors for hearing loss in workers with noise exposure in refining and chemical industry.

  9. Mutation induction in haploid yeast after split-dose radiation exposure. II. Combination of UV-irradiation and X-rays.

    Science.gov (United States)

    Keller, B; Zölzer, F; Kiefer, J

    2004-01-01

    Split-dose protocols can be used to investigate the kinetics of recovery from radiation damage and to elucidate the mechanisms of cell inactivation and mutation induction. In this study, a haploid strain of the yeast, Saccharomyces cerevisiae, wild-type with regard to radiation sensitivity, was irradiated with 254-nm ultraviolet (UV) light and then exposed to X-rays after incubation for 0-6 hr. The cells were incubated either on nutrient medium or salt agar between the treatments. Loss of reproductive ability and mutation to canavanine resistance were measured. When the X-ray exposure immediately followed UV-irradiation, the X-ray survival curves had the same slope irrespective of the pretreatment, while the X-ray mutation induction curves were changed from linear to linear quadratic with increasing UV fluence. Incubations up to about 3 hr on nutrient medium between the treatments led to synergism with respect to cell inactivation and antagonism with respect to mutation, but after 4-6 hr the two treatments acted independently. Incubation on salt agar did not cause any change in the survival curves, but there was a strong suppression of X-ray-induced mutation with increasing UV fluence. On the basis of these results, we suggest that mutation after combined UV and X-ray exposure is affected not only by the induction and suppression of DNA repair processes, but also by radiation-induced modifications of cell-cycle progression and changes in the expression of the mutant phenotype. Copyright 2004 Wiley-Liss, Inc.

  10. Factors affecting color strength of printing on film-coated tablets by UV laser irradiation: TiO2 particle size, crystal structure, or concentration in the film, and the irradiated UV laser power.

    Science.gov (United States)

    Hosokawa, Akihiro; Kato, Yoshiteru

    2011-08-01

    The purpose of this article is to study factors affecting color strength of printing on film-coated tablets by ultraviolet (UV) laser irradiation: particle size, crystal structure, or concentration of titanium dioxide (TiO2) in film, and irradiated UV laser power. Hydroxypropylmethylcellulose films containing 4.0% of TiO2, of which BET particle sizes were ranging from 126.1 to 219.8 nm, were irradiated 3.14W of UV laser at a wavelength 355 nm to study effects of TiO2 particle size and crystal structure on the printing. The films containing TiO2 concentration ranging from 1.0 to 7.7% were irradiated 3.14 or 5.39W of the UV laser to study effect of TiO2 concentration on the printing. The film containing 4.0% of TiO2, was irradiated the UV laser up to 6.42W to study effect of the UV laser power on the printing. The color strength of the printed films was estimated by a spectrophotometer as total color difference (dE). Particle size, crystal structure, and concentration of TiO2 in the films did not affect the printing. In the relationship between the irradiated UV laser power and dE, there found an inflection point (1.6W). When the UV laser power was below 1.6W, the films were not printed. When it was beyond the point, total color difference increased linearly in proportion with the irradiated laser power. The color strength of the printing on film was not changed by TiO2 particle size, crystal structure, and concentration, but could be controlled by regulating the irradiated UV laser power beyond the inflection point.

  11. Association of dental enamel lead levels with risk factors for environmental exposure.

    Science.gov (United States)

    Olympio, Kelly Polido Kaneshiro; Naozuka, Juliana; Oliveira, Pedro Vitoriano; Cardoso, Maria Regina Alves; Bechara, Etelvino José Henriques; Günther, Wanda Maria Risso

    2010-10-01

    To analyze household risk factors associated with high lead levels in surface dental enamel. A cross-sectional study was conducted with 160 Brazilian adolescents aged 1418 years living in poor neighborhoods in the city of Bauru, southeastern Brazil, from August to December 2008. Body lead concentrations were assessed in surface dental enamel acid-etch microbiopsies. Dental enamel lead levels were measured by graphite furnace atomic absorption spectrometry and phosphorus levels were measured by inductively coupled plasma optical emission spectrometry. The parents answered a questionnaire about their children's potential early (05 years old) exposure to well-known lead sources. Logistic regression was used to identify associations between dental enamel lead levels and each environmental risk factor studied. Social and familial covariables were included in the models. The results suggest that the adolescents studied were exposed to lead sources during their first years of life. Risk factors associated with high dental enamel lead levels were living in or close to a contaminated area (OR = 4.49; 95% CI: 1.69;11.97); and member of the household worked in the manufacturing of paints, paint pigments, ceramics or batteries (OR = 3.43; 95% CI: 1.31;9.00). Home-based use of lead-glazed ceramics, low-quality pirated toys, anticorrosive paint on gates and/or sale of used car batteries (OR = 1.31; 95% CI: 0.56;3.03) and smoking (OR = 1.66; 95% CI: 0.52;5.28) were not found to be associated with high dental enamel lead levels. Surface dental enamel can be used as a marker of past environmental exposure to lead and lead concentrations detected are associated to well-known sources of lead contamination.

  12. Association of dental enamel lead levels with risk factors for environmental exposure

    Directory of Open Access Journals (Sweden)

    Kelly Polido Kaneshiro Olympio

    2010-10-01

    Full Text Available OBJECTIVE: To analyze household risk factors associated with high lead levels in surface dental enamel. METHODS: A cross-sectional study was conducted with 160 Brazilian adolescents aged 14-18 years living in poor neighborhoods in the city of Bauru, southeastern Brazil, from August to December 2008. Body lead concentrations were assessed in surface dental enamel acid-etch microbiopsies. Dental enamel lead levels were measured by graphite furnace atomic absorption spectrometry and phosphorus levels were measured by inductively coupled plasma optical emission spectrometry. The parents answered a questionnaire about their children's potential early (05 years old exposure to well-known lead sources. Logistic regression was used to identify associations between dental enamel lead levels and each environmental risk factor studied. Social and familial covariables were included in the models. RESULTS: The results suggest that the adolescents studied were exposed to lead sources during their first years of life. Risk factors associated with high dental enamel lead levels were living in or close to a contaminated area (OR = 4.49; 95% CI: 1.69;11.97; and member of the household worked in the manufacturing of paints, paint pigments, ceramics or batteries (OR = 3.43; 95% CI: 1.31;9.00. Home-based use of lead-glazed ceramics, low-quality pirated toys, anticorrosive paint on gates and/or sale of used car batteries (OR = 1.31; 95% CI: 0.56;3.03 and smoking (OR = 1.66; 95% CI: 0.52;5.28 were not found to be associated with high dental enamel lead levels. CONCLUSIONS: Surface dental enamel can be used as a marker of past environmental exposure to lead and lead concentrations detected are associated to well-known sources of lead contamination.

  13. Novice drivers' exposure to known risk factors during the first 18 months of licensure: the effect of vehicle ownership.

    Science.gov (United States)

    Klauer, Sheila G; Simons-Morton, Bruce; Lee, Suzanne E; Ouimet, Marie Claude; Howard, E Henry; Dingus, Thomas A

    2011-04-01

    Though there is ample research indicating that nighttime, teen passengers, and speeding increase the risk of crash involvement, there is little research about teen drivers' exposure to these known risk factors. Three research questions were assessed in this article: (1) Does exposure to known risk factors change over time? (2) Do teenage drivers experience higher rates of exposure to known risk factors than adult drivers? (3) Do teenage drivers who own a vehicle experience higher rates of exposure to risk factors than those who share a family vehicle? Forty-one newly licensed teenage drivers and at least one parent (adult) were recruited at licensure. Driving data were recorded for 18 months. Average vehicle miles traveled (VMT) or average nighttime VMT for teens did not increase over time. Teenagers consistently drove 24 percent of VMT at night, compared with 18 percent for adults. Teenagers drove 62 percent of VMT with no passengers, 29 percent of VMT with one passenger, and less than 10 percent of VMT with multiple passengers. Driving with no passengers increased with driving experience for these teens. Teenage drivers who owned their vehicles, relative to those who shared a vehicle, sped 4 times more frequently overall and more frequently at night and with multiple teen passengers. These findings are among the first objective data documenting the nature of teenage driving exposure to known risk factors. The findings provide evidence that vehicle access is related to risk and suggest the potential safety benefit of parental management of novice teenage driving exposure.

  14. Time, dose and volume factors in interstitial brachytherapy combined with external irradiation for oral tongue carcinoma

    International Nuclear Information System (INIS)

    Yorozu, Atsunori

    1996-01-01

    This is a retrospective analysis of 136 patients with squamous cell carcinoma of stages I and II of the oral tongue who were treated with interstitial brachytherapy alone or in combination with external irradiation between 1976 and 1991. Control of the primary lesion and the occurrence of late complications were analyzed with respect to dose, time and tumor size with the Cox hazard model. The 5-year survival rates for stages I and II were 84.5% and 75.6%. The 5-year primary control rate was 91.3% for stage I and 77.3% for stage II (p 50 Gy compared with a brachytherapy dose 30 mm. Late complications should be reduced by using a spacer, improvements in dental and oral hygiene, and a sophisticated implant method. (author)

  15. Radiation optic neuropathy after megavoltage external-beam irradiation: Analysis of time-dose factors

    International Nuclear Information System (INIS)

    Parsons, J.T.; Bova, F.J.; Million, R.R.

    1994-01-01

    To investigate the risk of radiation-induced optic neuropathy according to total radiotherapy dose and fraction size, based on both retrospective and prospectively collected data. Between October 1964 and May 1989, 215 optic nerves in 131 patients received fractionated external-beam irradiation during the treatment of primary extracranial head and neck tumors. All patients had a minimum of 3 years of ophthalmologic follow-up (range, 3 to 21 years). The clinical end point was visual acuity of 20/100 or worse as a result of optic nerve injury. Anterior ischemic optic neuropathy developed in five nerves (at mean and median times of 32 and 30 months, respectively, and a range of 2-4 years). Retrobulbar optic neuropathy developed in 12 nerves (at mean and median times of 47 and 28 months, respectively, and a range of 1-14 years). No injuries were observed in 106 optic nerves that received a total dose of <59 Gy. Among nerves that received doses of ≥ 60 Gy, the dose per fraction was more important than the total dose in producing optic neuropathy. The 15-year actuarial risk of optic compared with 47% when given in fraction sizes ≥1.9 Gy. The data also suggest an increased risk of optic nerve injury with increasing age. As there is no effective treatment of radiation-induced optic neuropathy, efforts should be directed at its prevention by minimizing the total dose, paying attention to the dose per fraction to the nerve, and using reduced field techniques where appropriate to limit the volume of tissues that receive high-dose irradiation. 32 refs., 5 figs., 5 tabs

  16. Focal exposure of limited lung volumes to high-dose irradiation down-regulated organ development-related functions and up-regulated the immune response in mouse pulmonary tissues.

    Science.gov (United States)

    Kim, Bu-Yeo; Jin, Hee; Lee, Yoon-Jin; Kang, Ga-Young; Cho, Jaeho; Lee, Yun-Sil

    2016-01-27

    Despite the emergence of stereotactic body radiotherapy (SBRT) for treatment of medically inoperable early-stage non-small-cell lung cancer patients, the molecular effects of focal exposure of limited lung volumes to high-dose radiation have not been fully characterized. This study was designed to identify molecular changes induced by focal high-dose irradiation using a mouse model of SBRT. Central areas of the mouse left lung were focally-irradiated (3 mm in diameter) with a single high-dose of radiation (90 Gy). Temporal changes in gene expression in the irradiated and non-irradiated neighboring lung regions were analyzed by microarray. For comparison, the long-term effect (12 months) of 20 Gy radiation on a diffuse region of lung was also measured. The majority of genes were down-regulated in the focally-irradiated lung areas at 2 to 3 weeks after irradiation. This pattern of gene expression was clearly different than gene expression in the diffuse region of lungs exposed to low-dose radiation. Ontological and pathway analyses indicated these down-regulated genes were mainly associated with organ development. Although the number was small, genes that were up-regulated after focal irradiation were associated with immune-related functions. The temporal patterns of gene expression and the associated biological functions were also similar in non-irradiated neighboring lung regions, although statistical significance was greatly reduced when compared with those from focally-irradiated areas of the lung. From network analysis of temporally regulated genes, we identified inter-related modules associated with diverse functions, including organ development and the immune response, in both the focally-irradiated regions and non-irradiated neighboring lung regions. Focal exposure of lung tissue to high-dose radiation induced expression of genes associated with organ development and the immune response. This pattern of gene expression was also observed in non-irradiated

  17. Tobacco use and exposure to tobacco promoting and restraining factors among adolescents in a developing country.

    Science.gov (United States)

    Doku, D; Koivusilta, L; Raisamo, S; Rimpelä, A

    2012-08-01

    With a long history of tobacco cultivation, adolescents in Ghana are at relatively high risk of the emerging tobacco epidemic in developing countries. This study explored exposure to tobacco promoting/restraining factors and their associations with smoking and tawa (traditional smokeless tobacco) use among 13-18-year-old Ghanaians. School-based representative data were collected in 2008 (n = 1165). Prevalence rates of tobacco use, smoking and tawa use were 9.1% (11.5% boys and 6.4% girls), 6.6% (8.0% boys and 4.7% girls) and 5.7% (7.3% boys and 3.9% girls), respectively. Four percent of the respondents attended schools without a smoking ban, 66% had been taught about the harmful effects of smoking in the current school year, and 53% had been exposed to tobacco advertising. Fifty-three percent of adolescents who had tried to purchase tobacco products were not refused because of their age. Multivariate analyses found that attendance at a school where smoking was allowed, not having been taught about the harmful effects of smoking, exposure to tobacco advertising and parental smoking were positively associated with tobacco use, and knowledge that smoking is harmful to health and difficult to quit were negatively associated with tobacco use. Both smoking and tawa use were relatively low among Ghanaian adolescents. Exposure to tobacco advertising was high. There is no tobacco legislation in Ghana, but societal norms or cultural values seem to restrict smoking in schools and access to tobacco products. Copyright © 2012 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  18. Childhood Exposure to Phthalates: Associations with Thyroid Function, Insulin-like Growth Factor I, and Growth

    Science.gov (United States)

    Boas, Malene; Frederiksen, Hanne; Feldt-Rasmussen, Ulla; Skakkebæk, Niels E.; Hegedüs, Laszlo; Hilsted, Linda; Juul, Anders; Main, Katharina M.

    2010-01-01

    Background Phthalates are widely used chemicals, and human exposure is extensive. Recent studies have indicated that phthalates may have thyroid-disrupting properties. Objective We aimed to assess concentrations of phthalate metabolites in urine samples from Danish children and to investigate the associations with thyroid function, insulin-like growth factor I (IGF-I), and growth. Methods In 845 children 4–9 years of age, we determined urinary concentrations of 12 phthalate metabolites and serum levels of thyroid-stimulating hormone, thyroid hormones, and IGF-I. Results Phthalate metabolites were detected in all urine samples, of which monobutyl phthalate was present in highest concentration. Phthalate metabolites were negatively associated with serum levels of free and total triiodothyronine, although statistically significant primarily in girls. Metabolites of di(2-ethylhexyl) phthalate and diisononyl phthalate were negatively associated with IGF-I in boys. Most phthalate metabolites were negatively associated with height, weight, body surface, and height gain in both sexes. Conclusions Our study showed negative associations between urinary phthalate concentrations and thyroid hormones, IGF-I, and growth in children. Although our study was not designed to reveal the mechanism of action, the overall coherent negative associations between urine phthalate and thyroid and growth parameters may suggest causative negative roles of phthalate exposures for child health. PMID:20621847

  19. Prognostic factors for hearing preservation following observation-only versus stereotactic irradiation (STI) in patients with acoustic neuroma

    International Nuclear Information System (INIS)

    Sakamoto, Tooru

    1998-01-01

    Prognostic factors for hearing preservation following observation-only versus STI were compared in patients with acoustic neuroma. There were 48 patients with acoustic neuroma treated by fractionated STI. Between 1991 and 1997, patients were given 36 Gy in 20 fractions over 5 weeks (36 Gy/20 Fr/5 wks) to 44 Gy/22 Fr/6 wks followed by a 4 Gy boost. A linear accelerator was used for irradiation. Twenty-three patients with acoustic neuroma who were followed without any treatment (observation-only group) were selected as matched controls. The largest hearing loss was observed at the frequency of 2 kHz in the observation-only group and at 1-2 kHz in the STI group. Hearing loss at lkHz was more frequent in the STI group (p<0.01). There were no significant prognostic factors which predicted hearing preservation in the observation-only group. Stereotactic irradiation has been suggested to damage to cochlear nerve function in patients whose cochlear nerve had been impaired already. Tumor control rate of STI appeared to be as good as single fraction radiosurgery rates in the literature and better than in the observation-only group. Hearing preservation rate in the STI group was as good as in the observation-only group and appeared to be better than single fraction radiosurgery. In conclusion, because there were no factors predictive of hearing preservation in the observation-only group, it is difficult to select patients for observation only. Fractionated STI is potentially the treatment of choice, resulting in the same hearing preservation rate as achieved with observation only, although longer follow-up periods are needed. (author)

  20. Dosimeter irradiations for the 1996-1998 IAEA co-ordinated research project on intercomparison for individual monitoring of external exposure from photon radiation

    International Nuclear Information System (INIS)

    Aleinikov, V.E.; Ambrosi, P.; Buermann, L.; Bartlett, D.T.; McClure, D.R.; Csete, I.; Fominykh, V.I.; Oborin, A.V.; Stadtmann, H.

    1999-01-01

    This paper gives information on the facilities used by the irradiating laboratories, how the irradiations in both Phase II and Phase III were performed, as well as the procedures followed to ensure that all irradiations were done so that any uncertainty in the dose estimates of the irradiating laboratories, for the purpose of this intercomparison, can be negligible. (author)

  1. Summary Report of a Peer Involvement Workshop on the Development of An Exposure Factors Handbook for the Aging

    Science.gov (United States)

    EPA has released the final workshop report, Summary Report of a Peer Involvement Workshop on the Development of an Exposure Factors Handbook for the Aging. This report provides an overview of a meeting held February 14-15, 2007 which was organized to discuss factors affec...

  2. Prenatal exposure to residential air pollution and infant mental development: modulation by antioxidants and detoxification factors.

    Science.gov (United States)

    Guxens, Mònica; Aguilera, Inmaculada; Ballester, Ferran; Estarlich, Marisa; Fernández-Somoano, Ana; Lertxundi, Aitana; Lertxundi, Nerea; Mendez, Michelle A; Tardón, Adonina; Vrijheid, Martine; Sunyer, Jordi

    2012-01-01

    Air pollution effects on children's neurodevelopment have recently been suggested to occur most likely through the oxidative stress pathway. We aimed to assess whether prenatal exposure to residential air pollution is associated with impaired infant mental development, and whether antioxidant/detoxification factors modulate this association. In the Spanish INfancia y Medio Ambiente (INMA; Environment and Childhood) Project, 2,644 pregnant women were recruited during their first trimester. Nitrogen dioxide (NO2) and benzene were measured with passive samplers covering the study areas. Land use regression models were developed for each pollutant to predict average outdoor air pollution levels for the entire pregnancy at each residential address. Maternal diet was obtained at first trimester through a validated food frequency questionnaire. Around 14 months, infant mental development was assessed using Bayley Scales of Infant Development. Among the 1,889 children included in the analysis, mean exposure during pregnancy was 29.0 μg/m3 for NO2 and 1.5 μg/m3 for benzene. Exposure to NO2 and benzene showed an inverse association with mental development, although not statistically significant, after adjusting for potential confounders [β (95% confidence interval) = -0.95 (-3.90, 1.89) and -1.57 (-3.69, 0.56), respectively, for a doubling of each compound]. Stronger inverse associations were estimated for both pollutants among infants whose mothers reported low intakes of fruits/vegetables during pregnancy [-4.13 (-7.06, -1.21) and -4.37 (-6.89, -1.86) for NO2 and benzene, respectively], with little evidence of associations in the high-intake group (interaction p-values of 0.073 and 0.047). Inverse associations were also stronger in non-breast-fed infants and infants with low maternal vitamin D, but effect estimates and interactions were not significant. Our findings suggest that prenatal exposure to residential air pollutants may adversely affect infant mental

  3. Cannabis exposure as an interactive cardiovascular risk factor and accelerant of organismal ageing: a longitudinal study.

    Science.gov (United States)

    Reece, Albert Stuart; Norman, Amanda; Hulse, Gary Kenneth

    2016-11-07

    Many reports exist of the cardiovascular toxicity of smoked cannabis but none of arterial stiffness measures or vascular age (VA). In view of its diverse toxicology, the possibility that cannabis-exposed patients may be ageing more quickly requires investigation. Cross-sectional and longitudinal, observational. Prospective. Single primary care addiction clinic in Brisbane, Australia. 11 cannabis-only smokers, 504 tobacco-only smokers, 114 tobacco and cannabis smokers and 534 non-smokers. known cardiovascular disease or therapy or acute exposure to alcohol, amphetamine, heroin or methadone. Radial arterial pulse wave tonometry (AtCor, SphygmoCor, Sydney) performed opportunistically and sequentially on patients between 2006 and 2011. Algorithmically calculated VA. other central haemodynamic variables. Differences between group chronological ages (CA, 30.47±0.48 to 40.36±2.44, mean±SEM) were controlled with linear regression. Between-group sex differences were controlled by single-sex analysis. Mean cannabis exposure among patients was 37.67±7.16 g-years. In regression models controlling for CA, Body Mass Index (BMI), time and inhalant group, the effect of cannabis use on VA was significant in males (p=0.0156) and females (p=0.0084). The effect size in males was 11.84%. A dose-response relationship was demonstrated with lifetime exposure (pcannabis was robust to adjustment and was unrelated to its acute effects. Significant power interactions between cannabis exposure and the square and cube of CA were demonstrated (from pCannabis is an interactive cardiovascular risk factor (additional to tobacco and opioids), shows a prominent dose-response effect and is robust to adjustment. Cannabis use is associated with an acceleration of the cardiovascular age, which is a powerful surrogate for the organismal-biological age. This likely underlies and bi-directionally interacts with its diverse toxicological profile and is of considerable public health and regulatory

  4. C-reactive protein and serum amyloid A as early-phase and prognostic indicators of acute radiation exposure in nonhuman primate total-body irradiation model

    Energy Technology Data Exchange (ETDEWEB)

    Ossetrova, N.I., E-mail: ossetrova@afrri.usuhs.mil [Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bldg. 42, Bethesda, MD 20889-5603 (United States); Sandgren, D.J.; Blakely, W.F. [Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bldg. 42, Bethesda, MD 20889-5603 (United States)

    2011-09-15

    Terrorist radiological attacks or nuclear accidents could expose large numbers of people to ionizing radiation. In mass-casualty radiological incidents early medical-management requires triage tools for first-responders to quantitatively identify individuals exposed to life-threatening radiation doses and for early initiation (i.e., within one day after radiation exposure) of cytokine therapy for treatment of bone marrow acute radiation syndrome. Herein, we present results from 30 rhesus macaques total-body irradiated (TBI) to a broad dose range of 1-8.5 Gy with {sup 60}Co {gamma}-rays (0.55 Gy min{sup -1}) and demonstrate dose- and time-dependent changes in blood of C-reactive protein (CRP), serum amyloid A (SAA), and interleukin 6 (IL-6) measured by enzyme linked immunosorbent assay (ELISA). CRP and SAA dose-response results are consistent with {approx}1 Gy and {approx}0.2 Gy thresholds for photon-exposure at 24 h after TBI, respectively. Highly significant elevations of CRP and SAA (p = 0.00017 and p = 0.0024, respectively) were found in animal plasma at 6 h after all TBI doses suggesting their potential use as early-phase biodosimeters. Results also show that the dynamics and content of CRP and SAA levels reflect the course and severity of the acute radiation sickness (ARS) and may function as prognostic indicators of ARS outcome. These results demonstrate proof-of-concept that these radiation-responsive proteins show promise as a complementary approach to conventional biodosimetry for early assessment of radiation exposures and may also contribute as diagnostic indices in the medical management of radiation accidents.

  5. Relative Expression of Apoptotic and Vascular Epithelial Growth Factor Receptor Genes in Gamma-Irradiated Rat Kidney

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Hyang; Chun, Ki Jung; Kim, Jin Kyu [Korea Atomic research Institute, Deajeon (Korea, Republic of); Yoon, Yong Dal [Hanyang Univ., Seoul (Korea, Republic of)

    2005-07-01

    Biological process of wound healing, which occurs in three phases of revascularization (inflammatory, proliferative, and maturation) is an important essential step in regulating this process. Blood vessels serve as carriers for various cells, cytokines, and growth factors that are needed for tissue repair. The formation of new blood vessels is a necessary event during embryogenesis, but it occurs rarely in the adult with few exceptions, such as in the female reproductive system and wound healing. Angiogenesis is controlled by a variety of mitogenic, chemotactic, and inhibitory peptide and lipid factors that act on invading endothelial and smooth muscle cells. One of the most important angiogenic factors is the vascular endothelial growth factor (VEGF), a glycosylated protein of 46-48 kD composed of two disulphide linked subunits. The VEGF family consists of six members, five splicing forms of VEGF and the placenta-derived growth factor (PDGF). In normal, VEGF is expressed during embryogenesis and in a limited number of sites in adults. In disease states, VEGF can be detected in various tumor cells, the synovial pannus in rheumatoid arthritis, and in keratinocytes during wound healing. Five different VEGF isoforms, with 121, 145, 165, 189, and 106 amino acids, can be generated as a result of an alternative splicing from the single VEGF gene. The VEGF molecules bind to receptors known as VEFGR- 1 (FLT-1, fms-like tyrosine kinase 1), VEGFR-2 (KDR, kinase domain region/FLK-1, fetal liver kinase 1), VEGFR-2 (FLT-4), neurophilin-1, neurophilin-2, and heparan sulfate proteoglycans. Ionizing radiation can affect the angiogenesis and neovascularization on normal tissues in radiotherapy or by background radiation surrounding living beings. Kidney belongs to the urinary system and classified to the radio-resistant organ according to the previous studies. Therefore, the present study tested the effect of gamma irradiation and mercury chloride (MgCl{sub 2}) to the renal region

  6. A new Bayesian model applied to cytogenetic partial body irradiation estimation

    International Nuclear Information System (INIS)

    Higueras, Manuel; Puig, Pedro; Ainsbury, Elizabeth A.; Vinnikov, Volodymyr A.; Rothkamm, Kai

    2016-01-01

    A new zero-inflated Poisson model is introduced for the estimation of partial body irradiation dose and fraction of body irradiated. The Bayes factors are introduced as tools to help determine whether a data set of chromosomal aberrations obtained from a blood sample reflects partial or whole body irradiation. Two examples of simulated cytogenetic radiation exposure data are presented to demonstrate the usefulness of this methodology in cytogenetic biological dosimetry. (authors)

  7. Ion irradiated graphite exposed to fusion-relevant deuterium plasma

    International Nuclear Information System (INIS)

    Deslandes, Alec; Guenette, Mathew C.; Corr, Cormac S.; Karatchevtseva, Inna; Thomsen, Lars; Ionescu, Mihail; Lumpkin, Gregory R.; Riley, Daniel P.

    2014-01-01

    Graphite samples were irradiated with 5 MeV carbon ions to simulate the damage caused by collision cascades from neutron irradiation in a fusion environment. The ion irradiated graphite samples were then exposed to a deuterium plasma in the linear plasma device, MAGPIE, for a total ion fluence of ∼1 × 10 24 ions m −2 . Raman and near edge X-ray absorption fine structure (NEXAFS) spectroscopy were used to characterize modifications to the graphitic structure. Ion irradiation was observed to decrease the graphitic content and induce disorder in the graphite. Subsequent plasma exposure decreased the graphitic content further. Structural and surface chemistry changes were observed to be greatest for the sample irradiated with the greatest fluence of MeV ions. D retention was measured using elastic recoil detection analysis and showed that ion irradiation increased the amount of retained deuterium in graphite by a factor of four

  8. The effect of utilising age and sex dependent factors for calculating detriment from medical irradiation

    International Nuclear Information System (INIS)

    Mettler, F.A.; Davis, M.; Moseley, R.D.; Kelsey, C.A.

    1986-01-01

    Proposals have been made for a quantity that can be used to estimate possible detriment from medical radiology better than the ICRP's collective effective dose equivalent. One such approach utilises age and sex dependent 'weighting' factors. The magnitude of the effect obtained by utilising such factors when applied to an actual population has not been previously assessed. When age and sex dependent weighting factors are applied to diagnostic medical radiology for all hospital examinations conducted in the United States in 1980, estimates of detriment are reduced by one-third. (author)

  9. Functional Impact of Corticotropin-Releasing Factor Exposure on Tau Phosphorylation and Axon Transport.

    Directory of Open Access Journals (Sweden)

    Michelle H Le

    Full Text Available Stress exposure or increased levels of corticotropin-releasing factor (CRF induce hippocampal tau phosphorylation (tau-P in rodent models, a process that is dependent on the type-1 CRF receptor (CRFR1. Although these preclinical studies on stress-induced tau-P provide mechanistic insight for epidemiological work that identifies stress as a risk factor for Alzheimer's disease (AD, the actual impact of stress-induced tau-P on neuronal function remains unclear. To determine the functional consequences of stress-induced tau-P, we developed a novel mouse neuronal cell culture system to explore the impact of acute (0.5hr and chronic (2hr CRF treatment on tau-P and integral cell processes such as axon transport. Consistent with in vivo reports, we found that chronic CRF treatment increased tau-P levels and caused globular accumulations of phosphorylated tau in dendritic and axonal processes. Furthermore, while both acute and chronic CRF treatment led to significant reduction in CREB activation and axon transport of brain-derived neurotrophic factor (BDNF, this was not the case with mitochondrial transport. Acute CRF treatment caused increased mitochondrial velocity and distance traveled in neurons, while chronic CRF treatment modestly decreased mitochondrial velocity and greatly increased distance traveled. These results suggest that transport of cellular energetics may take priority over growth factors during stress. Tau-P was required for these changes, as co-treatment of CRF with a GSK kinase inhibitor prevented CRF-induced tau-P and all axon transport changes. Collectively, our results provide mechanistic insight into the consequences of stress peptide-induced tau-P and provide an explanation for how chronic stress via CRF may lead to neuronal vulnerability in AD.

  10. Effects of chronic aluminum exposure on learning and memory and brain-derived nerve growth factor in rats

    Institute of Scientific and Technical Information of China (English)

    潘宝龙

    2013-01-01

    Objective To investigate the effects of chronic aluminum exposure on the learning and memory abilities and brain-derived nerve growth factor (BDNF) in SpragueDawley (SD) rats.Methods Thirty-two male SD rats were randomly and equally divided into 4 groups:control group and high-,middle-,and low-dose exposure groups.The rats in high-,middle-,and low-dose expo-

  11. Irradiation in adulthood as a new model of schizophrenia.

    Directory of Open Access Journals (Sweden)

    Yasuhide Iwata

    Full Text Available BACKGROUND: Epidemiological studies suggest that radiation exposure may be a potential risk factor for schizophrenia in adult humans. Here, we investigated whether adult irradiation in rats caused behavioral abnormalities relevant to schizophrenia. METHODOLOGY/PRINCIPAL FINDINGS: A total dose of 15-Gy irradiation in six fractionations during 3 weeks was exposed to the forebrain including the subventricular zone (SVZ and subgranular zone (SGZ with male rats in the prone position. Behavioral, immunohistochemical, and neurochemical studies were performed three months after fractionated ionizing irradiation. Three months after fractionated ionizing irradiation, the total numbers of BrdU-positive cells in both the SVZ and SGZ zones of irradiated rats were significantly lower than those of control (sham-irradiated rats. Hyperactivity after administration of the dopaminergic agonist methamphetamine, but not the N-methyl-D-aspartate (NMDA receptor antagonist dizocilpine, was significantly enhanced in the irradiated rats although spontaneous locomotion in the irradiated rats was significantly lower than that of controls. Behavioral abnormalities including auditory sensory gating deficits, social interaction deficits, and working memory deficits were observed in the irradiated rats. CONCLUSION/SIGNIFICANCE: The present study suggests that irradiation in adulthood caused behavioral abnormalities relevant to schizophrenia, and that reduction of adult neurogenesis by irradiation may be associated with schizophrenia-like behaviors in rats.

  12. The prevalence of exposure to domestic violence and the factors associated with co-occurrence of psychological and physical violence exposure: a sample from primary care patients

    Science.gov (United States)

    2011-01-01

    Background Since many health problems are associated with abuse and neglect at all ages, domestic violence victims may be considered as a group of primary care patients in need of special attention. Methods The aim of this multi-centre study was to assess the prevalence of domestic violence in primary care patients, and to identify those factors which influence the co-occurrence of psychological and physical violence exposure and their consequences (physical, sexual and reproductive and psychological) as obtained from medical records. A study was carried out in 28 family practices in Slovenia in 2009. Twenty-eight family physicians approached every fifth family practice attendee, regardless of gender, to be interviewed about their exposure to domestic violence and asked to specify the perpetrator and the frequency. Out of 840 patients asked, 829 individuals, 61.0% women (n = 506) and 39.0% men (n = 323) were assessed (98.7% response rate). They represented a randomised sample of general practice attendees, aged 18 years and above, who had visited their physician for health problems and who were given a physical examination. Visits for administrative purposes were excluded. Multivariate binary logistic regression analysis was used to determine the factors associated with exposure to both psychological and physical violence. Results Of 829 patients, 15.3% reported some type of domestic violence experienced during the previous five years; 5.9% reported physical and 9.4% psychological violence; of these 19.2% of men and 80.8% of women had been exposed to psychological violence, while 22.4% of men and 77.6% of women had been exposed to physical violence. The domestic violence victims were mostly women (p violence was more prevalent than exposure to physical violence. Of the women, 20.0% were exposed to either type of violence, compared to 8.0% of male participants, who reported they were rarely exposed to physical violence, while women reported often or constant

  13. Persistent seroma after intraoperative placement of MammoSite for accelerated partial breast irradiation: Incidence, pathologic anatomy, and contributing factors

    International Nuclear Information System (INIS)

    Evans, Suzanne B.; Kaufman, Seth A.; Price, Lori Lyn; Cardarelli, Gene; Dipetrillo, Thomas A.; Wazer, David E.

    2006-01-01

    Purpose: To investigate the incidence of, and possible factors associated with, seroma formation after intraoperative placement of the MammoSite catheter for accelerated partial breast irradiation. Methods and Materials: This study evaluated 38 patients who had undergone intraoperative MammoSite catheter placement at lumpectomy or reexcision followed by accelerated partial breast irradiation with 34 Gy in 10 fractions. Data were collected regarding dosimetric parameters, including the volume of tissue enclosed by the 100%, 150%, and 200% isodose shells, dose homogeneity index, and maximal dose at the surface of the applicator. Clinical and treatment-related factors were analyzed, including patient age, patient weight, history of diabetes and smoking, use of reexcision, interval between surgery and radiotherapy, total duration of catheter placement, total excised specimen volume, and presence or absence of postprocedural infection. Seroma was verified by clinical examination, mammography, and/or ultrasonography. Persistent seroma was defined as seroma that was clinically detectable >6 months after radiotherapy completion. Results: After a median follow-up of 17 months, the overall rate of any detectable seroma was 76.3%. Persistent seroma (>6 months) occurred in 26 (68.4%) of 38 patients, of whom 46% experienced at least modest discomfort at some point during follow-up. Of these symptomatic patients, 3 required biopsy or complete cavity excision, revealing squamous metaplasia, foreign body giant cell reaction, fibroblasts, and active collagen deposition. Of the analyzed dosimetric, clinical, and treatment-related variables, only body weight correlated positively with the risk of seroma formation (p = 0.04). Postprocedural infection correlated significantly (p = 0.05) with a reduced risk of seroma formation. Seroma was associated with a suboptimal cosmetic outcome, because excellent scores were achieved in 61.5% of women with seroma compared with 83% without seroma

  14. Risk factors associated with airway allergic diseases from exposure to laboratory animal allergens among veterinarians.

    Science.gov (United States)

    Krakowiak, Anna; Wiszniewska, Marta; Krawczyk, Patrycja; Szulc, Bogdan; Wittczak, Tomasz; Walusiak, Jolanta; Pałczynski, Cezary

    2007-05-01

    Investigate the risk factors for the development of occupational airway allergy (OAA) from exposure to laboratory animal allergens (LAA) among Polish veterinarians. Two hundred veterinarians responded to the questionnaire and were subjected to skin prick test (SPT) to common allergens and LAA (rat, mouse, hamster, guinea pig, rabbit). Evaluation of total serum IgE level and specific IgE against occupational allergens was performed. In addition, bronchial hyperreactivity (BHR) and peak expiratory flow rate (PEFR) were measured before and after specific challenge testing (SCT) only in the subjects with work-related symptoms suggestive of occupational asthma (OA). The prevalence of asthmatic and ocular symptoms was statistically more prevalent in the group of veterinarians sensitised to LAA versus non-sensitised subjects. The most frequent occupational allergens of skin and serum reactivity were LAA (44.5 and 31.5%, respectively). In 41 (20.5%) and in 22 (11%) subjects out of 200 veterinarians, serum specific IgE to natural rubber latex (NRL) allergens and disinfectants was also found. Serum sensitisation to cat allergens and daily contact with laboratory animals (LA) increased the risk for developing isolated occupational rhinitis. Furthermore, working time of more than 10 years and daily contact with LA were also significant risk factors for the development of OAA. Measuring PEFR and BHR before and after SCT is a useful method to confirm the presence of OA. Allergy to LAA is an important health problem among veterinary medicine practitioners in Poland.

  15. [Changes of the Expression of Brain Derived Neurotrophic Factors in Rats Trachea Induced by Acrolein Exposure].

    Science.gov (United States)

    Yuan, Bing; Yang, Rui-an; Zhao, Wei; Xu, Yan-yan; Dan, Qi-qin; Zhang, Yun-hui

    2015-07-01

    To investigate expressional changes of brain derived neurotrophic factor (BDNF) in the trachea of rats with acrolein inhalation. Twenty two SD rats were divided into 2 groups: the rats in experimental group were subjected to acrolein inhalation for the induce of trachea inflammatory injury, while the rats with saline (NS) inhalation were as control. All the rats were sacrificed in 1,3,6 weeks after acrolein (n = 11 at each time point) or saline inhalation (n = 11 at each time point), the samples of trachea epithelium were harvested. The immunohistochemistry and in situ hybridization was performed to detect the location of BDNF protein and mRNA in trachea. The expression of BDNF mRNA in the trachea tissues were determined by RT-PCR. There are positive cells in epithelium of trachea for BDNF protein and mRNA, with cytoplasm staining. The expression of BDNF mRNA in the trachea was increased at 1 week after acrolein inhalation (P 0.05). The inflammatory injury in trachea induced by acrolein exposure could be associated with the increased expression of BDNF. BDNF may be one of the crucial inflammatory factors in the process of inflammatory reaction in trachea with acrolein stimulation.

  16. Radiation retinopathy after external-beam irradiation: Analysis of time-dose factors

    International Nuclear Information System (INIS)

    Parsons, J.T.; Bova, F.J.; Mendenhall, W.M.

    1994-01-01

    To investigate the risk of radiation-induced retinopathy according to total radiation dose and fraction size, based on both retorspective and prospectively collected data. Between October 1964 and May 1989, 68 retinae in 64 patients received fractionated external-beam irradiation during the treatment of primary extracranial head and neck tumors. All patients had a minimum of 3 years of ophthalmologic follow-up (range, 3 to 26 years; mean, 9 years; median, 8 years). Twenty-seven eyes in 26 patients developed radiation retinopathy resulting in visual acuity of 20/200 or worse. The mean and median times to the onset of symptoms attributable to retinal ischemia were 2.8 and 2.5 years, respectively. Fourteen of the injured eyes developed rubeosis iridis and/or neovascular glaucoma. Radiation retinopathy was not observed at doses below 45 Gy, but increased steadily in incidence at doses ≥45Gy. In the range of doses between 45 and 55 Gy, there was an increased risk of injury among patients who received doses per fraction of ≥1.9Gy (p - .09). There was also a trend toward increased risk of injury among patients who received chemotherapy (two of two vs. four of ten in the 45-51 Gy range; p - .23). The lowest dose associated with retinopathy was 45 Gy delivered to a diabetic patient by twice-a-day fractionation. The data did not suggest an increased risk of radiation retinopathy with increasing age. The current study suggests the importance of total dose as well as dose per fraction, and adds support to a small body of literature suggesting that patients with diabetes mellitus or who receive chemotherapy are at increased risk of injury. A sigmoid dose-response curve is constructed from our current data and data from the literature. 36 refs., 5 figs., 4 tabs

  17. Calculated dose factors for the radiosensitive tissues in bone irradiated by surface-deposited radionuclides

    International Nuclear Information System (INIS)

    Spiers, F.W.; Whitwell, J.R.; Beddoe, A.H.

    1978-01-01

    The method of calculating dose factors for the haemopoietic marrow and endosteal tissues in human trabecular bone, used by Whitwell and Spiers for volume-seeking radionuclides, has been developed for the case of radionuclides which are deposited as very thin layers on bone surfaces. The Monte Carlo method is again used, but modifications to the computer program are made to allow for a surface rather than a volume source of particle emission. The principal change is the introduction of a surface-orientation factor which is shown to have a value of approximately 2, varying slightly with bone structure. Results are given for β-emitting radionuclides ranging from 171 Tm(anti Esub(β) = 0.025 MeV) to 90 Y(anti Esub(β) = 0.93 MeV), and also for the α-emitter 239 Pu. It is shown that where the particle ranges are short compared with the dimensions of the bone structures the dose factors for the surface seekers are much greater than those for the volume seekers. For long range particles the dose factors for surface- and volume-seeking radionuclides converge. Comparisons are given relating the dose factors calculated in this paper on the basis of measured bone structures to those of other workers based on single plane geometry. (author)

  18. High-light damage in air-dry thalli of the old forest lichen Lobaria pulmonaria - interactions of irradiance, exposure duration and high temperature

    International Nuclear Information System (INIS)

    Gauslaa, Y.; Solhaug, K.A.

    1999-01-01

    High-light damage in air-dry thalli of Lobaria pulmonaria were measured in the laboratory as reductions in maximal PSII efficiency (FV/FM) after a 48 h recovery in a hydrated state at low light to account for permanent damage. Thalli treated with the lowest light dose (90 mol photons m −2 ) recovered normal FV/FM-values with increasing irradiances (400–700 nm) up to 1000 µmol photons m −2 s −1 . Doubling this dose lowered the threshold level for damage from 1000 to 320 µmol photons m −2 s −1 , and reduced FV/FM at 1000 µmol photons m −2 s −1 by more than 50%. A second doubling of the dose to 360 mol photons m −2 caused damage at 200 µmol photons m −2 s −1 , and a nearly complete cessation of PSII efficiency occurred at 1000 µmol photons m −2 s −1 . No reciprocity of irradiance and duration of illumination for PSII function was found. The measured time-dependent decrease in FV/FM was remarkably similar for the naturally coupled, but artificially separated, light and temperature factors. Therefore, the damage of high light on desiccated L. pulmonaria seemed to be an additive effect of high irradiance and high temperatures. Air-dry thalli were highly heat susceptible, being affected already at temperatures around 40 °C. Logging operations in forests are likely to raise the solar radiation at remaining lichen sites to destructive levels. (author)

  19. Dose conversion factors and linear energy transfer for irradiation of thin blood layers with low-energy X rays

    International Nuclear Information System (INIS)

    Verhaegen, F.; Seuntjens, J.

    1994-01-01

    For irradiation of thin samples of biological material with low-energy X rays, conversion of measured air kerma, free in air to average absorbed dose to the sample is necessary. In the present paper, conversion factors from measured air kerma to average absorbed dose in thin blood samples are given for four low-energy X-ray qualities (14-50 kVp). These factors were obtained by Monte Carlo simulation of a practical sample holder. Data for different thicknesses of the blood and backing layer are presented. The conversion factors are found to depend strongly on the thicknesses of the blood layer and backing layer. In radiobiological work, knowledge of linear energy transfer (LET) values for the radiation quality used is often required. Track-averaged LET values for low-energy X rays are presented in this work. It is concluded that the thickness of the sample does not influence the LET value appreciably, indicating that for all radiobiological purposes this value can be regarded as a constant throughout the sample. Furthermore, the large difference between the LET value for a 50 kV spectrum found in this work and the value given in ICRU Report 16 is pointed out. 16 refs., 7 figs., 1 tab

  20. The Efficiency of Irradiated Garlic Powder in Mitigation of Hypercholesterolemic Risk Factor in High cholesterol Fed Rats

    International Nuclear Information System (INIS)

    El-Neily, H.F.G.; El-Shennawy, H.M.

    2011-01-01

    -Neily and El-Shennawy, J. Rad. Res. Appl. Sci., Vol. 1272 4, No. 4(B)(2011) LDL/HDL ratio, AST and ALT activities in hypercholesterolemic rats. Irradiated dried garlic powder supplementation, also, increased HDL. In conclusion, irradiated dried garlic powder at 10, 15 and 20 kGy improved the plasma lipid levels in rats fed cholesterol-containing diets and increased the plasma HDL-C and reduced LDL/HDL ratio in groups of rats fed cholesterol-diets. The higher dose used (20 kGy) did not impair the bioactive compounds of dried garlic powder, and it can be used as an additive in cooking and as a protective pharmaceutical supplement for mitigation of hypercholesterolemic risk factor

  1. Irradiation of goods

    International Nuclear Information System (INIS)

    Huebner, G.

    1992-01-01

    The necessary dose and the dosage limits to be observed depend on the kind of product and the purpose of irradiation. Product density and density distribution, product dimensions, but also packaging, transport and storage conditions are specific parameters influencing the conditions of irradiation. The kind of irradiation plant - electron accelerator or gamma plant - , its capacity, transport system and geometric arrangement of the radiation field are factors influencing the irradiation conditions as well. This is exemplified by the irradiation of 3 different products, onions, deep-frozen chicken and high-protein feed. Feasibilities and limits of the irradiation technology are demonstrated. (orig.) [de

  2. Post irradiation conical keratosis

    International Nuclear Information System (INIS)

    Vestey, J.P.; Hunter, J.A.A.; Mallet, R.B.; Rodger, A.

    1989-01-01

    The authors have recently seen 3 patients affected by a widespread eruption of minute keratoses confined to areas of irradiated skin with clinical and histologial features of which they have been unable to find previous literary descriptions. A fourth patient with similar clinical and histopathological features occurring after exposure only to actinic irradiation is described. (author)

  3. Post irradiation conical keratosis

    Energy Technology Data Exchange (ETDEWEB)

    Vestey, J.P.; Hunter, J.A.A. (Royal Infirmary, Edinburgh (UK)); Mallet, R.B. (Westminster Hospital, London (UK)); Rodger, A. (Western General Hospital, Edinburgh (UK))

    1989-03-01

    The authors have recently seen 3 patients affected by a widespread eruption of minute keratoses confined to areas of irradiated skin with clinical and histologial features of which they have been unable to find previous literary descriptions. A fourth patient with similar clinical and histopathological features occurring after exposure only to actinic irradiation is described. (author).

  4. Prognostic factors for survival and intracerebral control after irradiation for brain metastases from gynecological cancer

    NARCIS (Netherlands)

    Rades, Dirk; Fischer, Dorothea; Veninga, Theo; Stalpers, Lukas J. A.; Schild, Steven E.

    2009-01-01

    The most appropriate treatment for the individual patient with brain metastases from gynecological cancer is unclear. Most of these patients receive whole-brain radiotherapy (WBRT) alone. Prognostic factors predicting the outcomes of these patients may guide the physician to select the appropriate

  5. Impact and effects of simultaneous MeV-ion irradiation and helium plasma exposure to the formation of tungsten nano-tendrils

    Science.gov (United States)

    Wright, Graham; Kesler, Leigh Ann; Whyte, Dennis

    2013-10-01

    The extrusion of nano-tendrils from high temperature (>1000 K) tungsten (W) targets exposed to helium (He) plasma ions remains a concern for future fusion reactors. Previous work on the Alcator C-Mod tokamak has demonstrated it is possible to form these structures in a tokamak environment. However, one area where Alcator C-Mod and a fusion reactor differ is total neutron flux at the wall and the displacement damage these neutrons produce in the plasma-facing materials. This dsiplacement damage may affect the size and number He bubbles precipitating in the W target, which is a key factor in the formation and growth of the nano-tendrils. The DIONISOS experiment directly measures the impact of the displacement damage by simultaneously bombarding high temperature W targets with MeV-range ions (to simulate the displacement damage caused by neutron flux) and high flux of He plasma ions. Different combinations of irradiating ion species and W target temperatures are used to vary the different processes and rates that are involved such as He trapping rate, vacancy production and annealing rates, and nano-tendril growth rate. The nano-tendril growth is characterized by SEM imaging and focused ion beam (FIB) cross-sectioning and compared to nano-tendril formation without the presence of the irradiating ion beam. This work is supported by US DOE award DE-SC00-02060.

  6. Effects of bacterial lipopolysaccharide and X-irradiation on the production of colony-stimulating factor and the maintenance of granulopoiesis in bone marrow culture

    International Nuclear Information System (INIS)

    Izumi, H.; Miyanomae, T.; Tsurusawa, M.; Fujita, J.; Mori, K.

    1984-01-01

    Effects of bacterial lipopolysaccharide (LPS) and X-irradiation on CSF production and granulopoiesis in long-term bone marrow cultures were studied. Levels of colony-stimulating factor (CSF) increased soon after the refeeding of the culture, but the activity was undetectable at day 7. Addition of LPS induced a significant increase in CSF levels in the culture, followed by an elevated granulopoiesis. The increase in CSF levels was suppressed when culture medium that had been harvested at refeeding on day 7 was added. Although irradiation did not increase CSF production, granulopoiesis was markedly stimulated shortly after irradiation. Thus granulopoiesis in long-term bone marrow culture may also be regulated by humoral factors such as CSF, and the culture system may represent the in vivo response to haemopoietic stimuli. (author)

  7. Use of an improved radiation amplification factor to estimate the effect of total ozone changes on action spectrum weighted irradiances and an instrument response function

    Science.gov (United States)

    Herman, Jay R.

    2010-12-01

    Multiple scattering radiative transfer results are used to calculate action spectrum weighted irradiances and fractional irradiance changes in terms of a power law in ozone Ω, U(Ω/200)-RAF, where the new radiation amplification factor (RAF) is just a function of solar zenith angle. Including Rayleigh scattering caused small differences in the estimated 30 year changes in action spectrum-weighted irradiances compared to estimates that neglect multiple scattering. The radiative transfer results are applied to several action spectra and to an instrument response function corresponding to the Solar Light 501 meter. The effect of changing ozone on two plant damage action spectra are shown for plants with high sensitivity to UVB (280-315 nm) and those with lower sensitivity, showing that the probability for plant damage for the latter has increased since 1979, especially at middle to high latitudes in the Southern Hemisphere. Similarly, there has been an increase in rates of erythemal skin damage and pre-vitamin D3 production corresponding to measured ozone decreases. An example conversion function is derived to obtain erythemal irradiances and the UV index from measurements with the Solar Light 501 instrument response function. An analytic expressions is given to convert changes in erythemal irradiances to changes in CIE vitamin-D action spectrum weighted irradiances.

  8. Transforming growth factor beta 1 expression and inflammatory cells in tooth extraction socket after X-ray irradiation

    Directory of Open Access Journals (Sweden)

    Ramadhan Hardani Putra

    2016-06-01

    Full Text Available Background: Radiographic examination is often used in dentistry to evaluate tooth extraction complications. X-ray used in radiographic examination, however, has negative effects, including damage to DNA and inflammatory response during wound healing process. Purpose: This study aimed to analyze the effects of X-ray irradiation on transforming growth factor beta 1 (TGF-ß1 expression and number of inflammatory cells in tooth extraction sockets. Method: Thirty rats were divided into three groups, which consist of control group (with a radiation of 0 mSv, treatment group 1 (with a radiation of 0.08 mSv, and treatment group 2 (with a radiation of 0.16 mSv. These rats in each group were sacrificed on days 3 and 5 after treatment. Inflammatory cells which were observed in this research were PMN, macrophages, and lymphocytes. Histopathological and immunohistochemical examinations were used to calculate the number of inflammatory cells and TGF-ß1 expression. Obtained data were analyzed using SPSS 16.0 software with one way ANOVA and Tukey’s HSD tests. Result: There was no significant decrease in the number of PMN. On the other hand, there were significant decreases in the number of macrophages and lymphocytes in the sacrificed group on day-5 with the radiation of 0.16 mSv. Similarly, the most significant decreased expression of TGF-ß1 was found in the group sacrificed on day 5 with the radiation of 0.16 mSv. Conclusion: X-ray irradiation with 0.08 mSv and 0.16 mSv doses can decrease TGF-ß1 expression and number of inflammatory cells in tooth extraction sockets on day 3 and 5 post extraction.

  9. Effects of Gamma Irradiation on Nutrient Composition, Anti-nutritional Factors, In vitro Digestibility and Ruminal Degradation of Whole Cotton Seed

    International Nuclear Information System (INIS)

    Hahm, S.W.; Son, H.Y.; Kim, W.; Son, Y.S.; Oh, Y.K.

    2013-01-01

    Whole cotton seed (WCS) has become one of the major feed ingredients in TMR for dairy cattle in Korea, and WCS for feed use is mostly imported from abroad. Since this genetically modified oil seed is usually fed to the animal in raw state, its germination ability, if last long, often causes concerns about ecological disturbances. In the process of looking for effective conditions to remove germination ability of WCS this study had the objectives to evaluate the nutritional effects of gamma irradiation at doses of 8, 10 and 12 kGy on changes in nutrient contents, anti-nutritional factors, in vitro digestibility and ruminal degradability. No significant differences were found in proximate analysis of nutrients between raw WCS and gamma irradiated one. Glycine and threonine contents significantly increased when the WCS was exposed to gamma ray as compared to untreated WCS(p0.05). As for fatty acid composition, no significant differences were observed with the irradiation treatment. Free gossypol in WCS was decreased(p0.05) by gamma irradiation treatment. Of the 3 different levels of gamma irradiation, a dose of 12kGy was found to be the most effective in reducing free gossypol concentration. Results obtained from in situ experiment indicated that gamma irradiation at a dose of 10 kGy significantly(p0.05) lowered rumen degradability of both dry matter and crude protein as compared with raw WCS. However, there were no significant differences in rapidly degradable and potentially degradable fractions of crude protein due to 10kGy gamma irradiation. Overall, this study show that gamma irradiation at a dose of 10kGy is the optimum condition for removing germination ability of WCS, and could improve nutritive value for the ruminant with respect to the decrease in both ruminal protein degradability and gossypol content of WCS

  10. Novice Drivers' Exposure to Known Risk Factors During the First 18 Months of Licensure: The Effect of Vehicle Ownership

    Science.gov (United States)

    Klauer, Sheila G.; Simons-Morton, Bruce; Lee, Suzanne E.; Ouimet, Marie Claude; Howard, E. Henry; Dingus, Thomas A.

    2014-01-01

    Objective Though there is ample research indicating that nighttime, teen passengers, and speeding increase the risk of crash involvement, there is little research about teen drivers' exposure to these known risk factors. Three research questions were assessed in this article: (1) Does exposure to known risk factors change over time? (2) Do teenage drivers experience higher rates of exposure to known risk factors than adult drivers? (3) Do teenage drivers who own a vehicle experience higher rates of exposure to risk factors than those who share a family vehicle? Methods Forty-one newly licensed teenage drivers and at least one parent (adult) were recruited at licensure. Driving data were recorded for 18 months. Results Average vehicle miles traveled (VMT) or average nighttime VMT for teens did not increase over time. Teenagers consistently drove 24 percent of VMT at night, compared with 18 percent for adults. Teenagers drove 62 percent of VMT with no passengers, 29 percent of VMT with one passenger, and less than 10 percent of VMT with multiple passengers. Driving with no passengers increased with driving experience for these teens. Teenage drivers who owned their vehicles, relative to those who shared a vehicle, sped 4 times more frequently overall and more frequently at night and with multiple teen passengers. Conclusion These findings are among the first objective data documenting the nature of teenage driving exposure to known risk factors. The findings provide evidence that vehicle access is related to risk and suggest the potential safety benefit of parental management of novice teenage driving exposure. PMID:21469023

  11. Dose and dose rate extrapolation factors for malignant and non-malignant health endpoints after exposure to gamma and neutron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Van; Little, Mark P. [National Cancer Institute, Radiation Epidemiology Branch, Rockville, MD (United States)

    2017-11-15

    Murine experiments were conducted at the JANUS reactor in Argonne National Laboratory from 1970 to 1992 to study the effect of acute and protracted radiation dose from gamma rays and fission neutron whole body exposure. The present study reports the reanalysis of the JANUS data on 36,718 mice, of which 16,973 mice were irradiated with neutrons, 13,638 were irradiated with gamma rays, and 6107 were controls. Mice were mostly Mus musculus, but one experiment used Peromyscus leucopus. For both types of radiation exposure, a Cox proportional hazards model was used, using age as timescale, and stratifying on sex and experiment. The optimal model was one with linear and quadratic terms in cumulative lagged dose, with adjustments to both linear and quadratic dose terms for low-dose rate irradiation (<5 mGy/h) and with adjustments to the dose for age at exposure and sex. After gamma ray exposure there is significant non-linearity (generally with upward curvature) for all tumours, lymphoreticular, respiratory, connective tissue and gastrointestinal tumours, also for all non-tumour, other non-tumour, non-malignant pulmonary and non-malignant renal diseases (p < 0.001). Associated with this the low-dose extrapolation factor, measuring the overestimation in low-dose risk resulting from linear extrapolation is significantly elevated for lymphoreticular tumours 1.16 (95% CI 1.06, 1.31), elevated also for a number of non-malignant endpoints, specifically all non-tumour diseases, 1.63 (95% CI 1.43, 2.00), non-malignant pulmonary disease, 1.70 (95% CI 1.17, 2.76) and other non-tumour diseases, 1.47 (95% CI 1.29, 1.82). However, for a rather larger group of malignant endpoints the low-dose extrapolation factor is significantly less than 1 (implying downward curvature), with central estimates generally ranging from 0.2 to 0.8, in particular for tumours of the respiratory system, vasculature, ovary, kidney/urinary bladder and testis. For neutron exposure most endpoints, malignant and

  12. Radiation Therapy Risk Factors for Development of Lymphedema in Patients Treated With Regional Lymph Node Irradiation for Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, Ravi A. [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Miller, Cynthia L. [Harvard Medical School, Boston, Massachusetts (United States); Skolny, Melissa N. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Warren, Laura E.G. [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Horick, Nora [Department of Biostatistics, Massachusetts General Hospital, Boston, Massachusetts (United States); Jammallo, Lauren S.; Sadek, Betro T.; Shenouda, Mina N. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); O' Toole, Jean [Department of Physical and Occupational Therapy, Massachusetts General Hospital, Boston, Massachusetts (United States); Specht, Michelle C. [Division of Surgical Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Taghian, Alphonse G., E-mail: ataghian@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2015-03-15

    Purpose: We previously evaluated the risk of breast cancer-related lymphedema (LE) with the addition of regional lymph node irradiation (RLNR) and found an increased risk when RLNR is used. Here we analyze the association of technical radiation therapy (RT) factors in RLNR patients with the risk of LE development. Methods and Materials: From 2005 to 2012, we prospectively screened 1476 women for LE who underwent surgery for breast cancer. Among 1507 breasts treated, 172 received RLNR and had complete technical data for analysis. RLNR was delivered as supraclavicular (SC) irradiation (69% [118 of 172 patients]) or SC plus posterior axillary boost (PAB) (31% [54 of 172]). Bilateral arm volume measurements were performed pre- and postoperatively. Patients' RT plans were analyzed for SC field lateral border (relative to the humeral head), total dose to SC, RT fraction size, beam energy, and type of tangent (normal vs wide). Cox proportional hazards models were used to analyze associated risk factors for LE. Results: Median postoperative follow-up was 29.3 months (range: 4.9-74.1 months). The 2-year cumulative incidence of LE was 22% (95% confidence interval [CI]: 15%-32%) for SC and 20% (95% CI: 11%-37%) for SC plus PAB (SC+PAB). None of the analyzed variables was significantly associated with LE risk (extent of humeral head: P=.74 for <1/3 vs >2/3, P=.41 for 1/3 to 2/3 vs >2/3; P=.40 for fraction size of 1.8 Gy vs 2.0 Gy; P=.57 for beam energy 6 MV vs 10 MV; P=.74 for tangent type wide vs regular; P=.66 for SC vs SC+PAB). Only pretreatment body mass index (hazard ratio [HR]: 1.09; 95% CI: 1.04-1.15, P=.0007) and the use of axillary lymph node dissection (HR: 7.08, 95% CI: 0.98-51.40, P=.05) were associated with risk of subsequent LE development. Conclusions: Of the RT parameters tested, none was associated with an increased risk of LE development. This study underscores the need for future work investigating alternative RLNR risk factors for LE.

  13. Irradiation device

    International Nuclear Information System (INIS)

    Ransohoff, J.A.

    1984-01-01

    Carriers, after being loaded with product to be irradiated, are transported by an input-output conveyor system into an irradiation chamber where they are received in a horizontal arrangement on racks which may support different sizes and numbers of carriers. The racks are moved by a chamber conveyor system in an endless rectangular path about a radiation source. Packers shift the carriers on the racks to maintain nearest proximity to the radiation source. The carriers are shifted in position on each rack during successive rack cycles to produce even radiation exposure. The carriers may be loaded singly onto successive racks during a first cycle of movement thereof about the source, with loading of additional carriers, and/or unloading of carriers, onto each rack occurring on subsequent rack cycles of movement

  14. Hydration and transparency of the rabbit cornea irradiated with UVB-doses of 0.25 J/cm(2) and 0.5 J/cm(2) compared with equivalent UVB radiation exposure reaching the human cornea from sunlight.

    Science.gov (United States)

    Cejka, Cestmír; Ardan, Taras; Sirc, Jakub; Michálek, Jiří; Beneš, Jiří; Brůnová, Blanka; Rosina, Jozef

    2011-07-01

    Exposure of the cornea to UV radiation from sunlight evokes intraocular inflammation, photokeratitis. Photokeratitis is caused by UVB radiation. It is accompanied by changes of corneal hydration and light absorption. The aim of this study was to examine the effect of two UVB doses on corneal optics in rabbits and to compare these UVB doses with the equivalent exposure of UVB radiation reaching the human cornea from sunlight. Rabbit corneas were irradiated with a daily UVB dose of 0.25 J/cm(2) or 0.5 J/cm(2) for 4 days. One day after finishing the irradiations the rabbits were sacrificed and corneal light absorption measured using our spectrophotometrical method. Corneal hydration was examined using an ultrasonic Pachymeter every experimental day before the irradiation procedure and the last day before sacrificing the animals. Changes in corneal optics appeared after the repeated exposure of the cornea to a UVB dose of 0.25 J/ cm(2) and massively increased after the repeated exposure of the cornea to a UVB dose of 0.5 J/cm(2). The first significant changes in corneal hydration appeared after a single exposure of the cornea to a UVB dose of 0.25 J/cm(2). Changes in corneal hydration appeared after the exposure of the rabbit cornea to a single UVB dose equivalent to 2.6 hours of solar UVB radiation reaching the human cornea, as measured by UVB sensors embedded in the eyes of mannequin heads facing the sun on a beach at noon in July. Repeated exposure of the rabbit cornea to the same UVB dose evoked profound changes in corneal optics. Although comparison of experimental and outdoor conditions are only approximate, the results in rabbits point to the danger for the human eye from UVB radiation when short stays in sunlight are repeated for several consecutive days without UV protection.

  15. Factors contributing to background television exposure in low-income Mexican American preschoolers

    Science.gov (United States)

    Thompson, Darcy A.; Tschann, Jeanne M.

    2016-01-01

    Objective Background television (TV) exposure is harmful to young children, yet few studies have focused on predictors of exposure. This study’s objectives were to elucidate demographic, environmental, and behavioral correlates of background TV exposure in low-income Mexican American preschoolers and to explore caregiver beliefs about the impact of such exposure. Methods A convenience sample of low-income Mexican American female primary caregivers of preschoolers (3–5 years old, n=309), recruited in safety-net clinics, were surveyed by phone. Caregivers reported the frequency of their child’s exposure to background TV and responded to questions on the home media environment, TV use, and whether they had thought about background TV exposure and its impact on their child. Results Background TV exposure was common; 43% reported that their child was often, very often, or always exposed to background TV. More hours of TV viewing by the caregiver and greater frequency of TV viewing during meals were associated with an increased frequency of exposure to background TV. Only 49% of participants had ever thought about the impact of background TV. Believing that background TV is not harmful was associated with higher levels of background TV exposure. Conclusions Findings suggest that background TV exposure is frequent and caregiver awareness of its potential impact is low in low-income Mexican American families. Beliefs that background TV is not harmful may predict risk of exposure. Potential targets for interventions focused on reducing background TV exposure in this population include increasing caregiver awareness of the potential negative impact of such TV exposure. PMID:27007983

  16. Particle size: a missing factor in risk assessment of human exposure to toxic chemicals in settled indoor dust.

    Science.gov (United States)

    Cao, Zhi-Guo; Yu, Gang; Chen, Yong-Shan; Cao, Qi-Ming; Fiedler, Heidelore; Deng, Shu-Bo; Huang, Jun; Wang, Bin

    2012-11-15

    For researches on toxic chemicals in settled indoor dust, selection of dust fraction is a critical influencing factor to the accuracy of human exposure risk assessment results. However, analysis of the selection of dust fraction in recent studies revealed that there is no consensus. This study classified and presented researches on distribution of toxic chemicals according to dust particle size and on relationship between dust particle size and human exposure possibility. According to the literature, beyond the fact that there were no consistent conclusions on particle size distribution of adherent fraction, dust with particle size less than 100 μm should be paid more attention and that larger than 250 μm is neither adherent nor proper for human exposure risk assessment. Calculation results based on literature data show that with different selections of dust fractions, analytical results of toxic chemicals would vary up to 10-fold, which means that selecting dust fractions arbitrarily will lead to large errors in risk assessment of human exposure to toxic chemicals in settled dust. Taking into account the influence of dust particle size on risk assessment of human exposure to toxic chemicals, a new methodology for risk assessment of human exposure to toxic chemicals in settled indoor dust is proposed and human exposure parameter systems to settled indoor dust are advised to be established at national and regional scales all over the world. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Irradiation and flavor

    International Nuclear Information System (INIS)

    Reineccius, G.A.

    1992-01-01

    Flavor will not be a significant factor in determining the success of irradiated foods entering the U.S. market. The initial applications will use low levels of irradiation that may well result in products with flavor superior to that of products from alternative processing techniques (thermal treatment or chemical fumigation). The success of shelf-stable foods produced via irradiation may be much more dependent upon our ability to deal with the flavor aspects of high levels of irradiation

  18. Effects of maternal smoking and exposure to methylmercury on brain-derived neurotrophic factor concentrations in umbilical cord serum

    DEFF Research Database (Denmark)

    Spulber, Stefan; Rantamäki, Tomi; Nikkilä, Outi

    2010-01-01

    . The cohort consisted of 395 singleton births (206 boys and 189 girls), gestational age ranging from 38 to 42 weeks. Serum BDNF was measured by sandwich ELISA. Maternal smoking habits and other relevant factors were obtained by interviewing the mothers. The exposure to MeHg was estimated from Hg...... concentrations in cord blood, whereas exposure to PCB was estimated based on maternal serum concentrations. Only MeHg exposure affected the serum BDNF, which decreased in a concentration-dependent manner in girls born to nonsmoking mothers. Maternal smoking significantly increased BNDF in girls but not in boys....... For further statistical analyses, we used the serum BDNF concentration as a continuous outcome variable in supervised regression models. Serum BDNF concentration increased with gestational age, increased by maternal smoking, decreased slightly with MeHg exposure, and maternal smoking enhanced the decrease...

  19. Prevalence and risk factors for viral exposure in rural dogs around protected areas of the Atlantic forest.

    Science.gov (United States)

    Curi, Nelson Henrique de Almeida; Massara, Rodrigo Lima; de Oliveira Paschoal, Ana Maria; Soriano-Araújo, Amanda; Lobato, Zélia Inês Portela; Demétrio, Guilherme Ramos; Chiarello, Adriano Garcia; Passamani, Marcelo

    2016-01-28

    Despite the crucial role of domestic dogs as reservoirs for zoonosis and some of the most threatening diseases for wild carnivores such as distemper and parvovirosis, little is known about the epidemiological features and the risk factors involved in pathogen exposure of dogs that live in human/wildlife interfaces and actually contacts wildlife. Through a cross-sectional serological approach and questionnaire survey, we assessed the prevalence along with individual and environment-associated risk factors for four important viral diseases of rural dogs living in households around six Atlantic Forest fragments in southeast Brazil. Widespread exposure to canine parvovirus (97%), canine distemper virus (15%) and canine adenovirus (27%) was detected, but none for canine coronavirus. Dogs from small private reserves were more exposed to parvovirus and canine distemper virus than those from larger state parks. Exposure was associated with dog sex and age, lack of health care and the number of people in the households. Remarkably, factors linked to free-ranging behaviour of dogs were associated with the exposure for all pathogens detected. According to identified associations, reducing viral pathogen exposure in dogs will require inhibiting dog's movements and access to nearby forests and villages and improving veterinary assistance. Promoting dog vaccination and population control through sterilization around protected areas is also necessary. The study provides support for preventive management actions aimed to protect the health of rural dogs, and consequently of Atlantic Forest's wild carnivores.

  20. Prognostic factors for outcomes after whole-brain irradiation of brain metastases from relatively radioresistant tumors: a retrospective analysis

    Directory of Open Access Journals (Sweden)

    Schild Steven E

    2010-10-01

    Full Text Available Abstract Background This study investigated potential prognostic factors in patients treated with whole-brain irradiation (WBI alone for brain metastases from relatively radioresistant tumors such as malignant melanoma, renal cell carcinoma, and colorectal cancer. Additionally, a potential benefit from escalating the radiation dose was investigated. Methods Data from 220 patients were retrospectively analyzed for overall survival and local control. Nine potential prognostic factors were evaluated: tumor type, WBI schedule, age, gender, Karnofsky performance score, number of brain metastases, extracerebral metastases, interval from diagnosis of cancer to WBI, and recursive partitioning analysis (RPA class. Results Survival rates at 6 and 12 months were 32% and 19%, respectively. In the multivariate analysis, WBI doses >30 Gy (p = 0.038, KPS ≥70 (p Conclusions Improved outcomes were associated with WBI doses >30 Gy, better performance status, fewer brain metastases, lack of extracerebral metastases, and lower RPA class. Patients receiving WBI alone appear to benefit from WBI doses >30 Gy. However, such a benefit is limited to RPA class 1 or 2 patients.

  1. Changes in activity of industrial enzyme preparations irradiated with sterilizing doses. Part of a coordinated programme on factors influencing the utilization of food irradiation process

    International Nuclear Information System (INIS)

    Bachman, S.

    1984-03-01

    Experiments were carried out to investigate the efficacy of irradiation to sterilize enzyme preparations. Irradiation doses up to 25 kGy caused no changes in basic organoleptic properties of commercial rennin preparations. Dose rate (from 0.5 to 13.5 kGy/hr) has no influence on the changes in enzyme activity during the storage period of 3 months. Doses ranging from 8 to 12 kGy are sufficient to sterilize commercial enzyme preparations. Non-purified, crude rennin preparations appear to be more resistant to radiation than purified samples. Rennin preparations purified by dialysis and treated with 25 kGy resulted in a reduction of activity of 20%. The activity of preparations purified by gel filtration was reduced to 50% when treated with the same dose

  2. The Situation of Pregnant Women Exposure to Violence by Husband and the Factors Associated With Violence

    Directory of Open Access Journals (Sweden)

    Tulay Sagkal

    2014-10-01

    Full Text Available AIM: This study was planned to determine the pregnant women living in rural areas exposure the situation to violence by husband and the factors associated with violence. METHODS: This descriptive cross-section research was conducted all of 5 Family Health Center located in the center of Odemis in izmir. The study sample consisted of 230 pregnant women who are willing to participate in the study, which surveyed admitted to Family Health Center between December 2011 - February 2012. Data are collected through a questionnaire prepared by examining the literature. The questionnaire consists of a total of 20 questions which including socio-demographic characteristics of pregnant women (8 questions, pregnancy, physical, emotional, economic and sexual violence, to determine (12 questions. Data were collected by face to face interviews by the researchers, were evaluated with number, percentage and chi-square tests. RESULTS: The average age of pregnant women was 25.75 +/- 4.63 (min:15-max:40, who was 83% of willingly got pregnant, 43% of first pregnancy, 79.6% of during pregnancy support of husband, 67% of the support of the family, % 32.6 of her husband doesn and #8217;t use substance but use alcohol, 10.9% of pregnant women reported physical, 52.6% of emotional, 31.7% of economic and 8.3% were exposed to sexual violence. CONCLUSiON: In this study, having pregnant woman and her husband to have graduated from primary school, moderate of the economic situation, unwilling pregnancy, lack of family support were the factors most strongly associated with violence. It is suggested that by health care institutions and health care providers must be routine screenings to determine violence during pregnancy. [TAF Prev Med Bull 2014; 13(5.000: 381-390

  3. Early Infant Exposure to Excess Multivitamin: A Risk Factor for Autism?

    Directory of Open Access Journals (Sweden)

    Shi-Sheng Zhou

    2013-01-01

    Full Text Available Autism, a neurodevelopmental disorder that affects boys more than girls, is often associated with altered levels of monoamines (serotonin and catecholamines, especially elevated serotonin levels. The monoamines act as both neurotransmitters and signaling molecules in the gastrointestinal and immune systems. The evidence related to monoamine metabolism may be summarized as follows: (i monoamine neurotransmitters are enzymatically degraded/inactivated by three mechanisms: oxidative deamination, methylation, and sulfation. The latter two are limited by the supply of methyl groups and sulfate, respectively. (ii A decrease in methylation- and sulfation-mediated monoamine inactivation can be compensated by an increase in the oxidative deamination catalyzed by monoamine oxidase, an X-linked enzyme exhibiting higher activity in females than in males. (iii Vitamins can, on one hand, facilitate the synthesis of monoamine neurotransmitters and, on the other hand, inhibit their inactivation by competing for methylation and sulfation. Therefore, we postulate that excess multivitamin feeding in early infancy, which has become very popular over the past few decades, may be a potential risk factor for disturbed monoamine metabolism. In this paper, we will focus on the relationship between excess multivitamin exposure and the inactivation/degradation of monoamine neurotransmitters and its possible role in the development of autism.

  4. Early infant exposure to excess multivitamin: a risk factor for autism?

    Science.gov (United States)

    Zhou, Shi-Sheng; Zhou, Yi-Ming; Li, Da; Ma, Qiang

    2013-01-01

    Autism, a neurodevelopmental disorder that affects boys more than girls, is often associated with altered levels of monoamines (serotonin and catecholamines), especially elevated serotonin levels. The monoamines act as both neurotransmitters and signaling molecules in the gastrointestinal and immune systems. The evidence related to monoamine metabolism may be summarized as follows: (i) monoamine neurotransmitters are enzymatically degraded/inactivated by three mechanisms: oxidative deamination, methylation, and sulfation. The latter two are limited by the supply of methyl groups and sulfate, respectively. (ii) A decrease in methylation- and sulfation-mediated monoamine inactivation can be compensated by an increase in the oxidative deamination catalyzed by monoamine oxidase, an X-linked enzyme exhibiting higher activity in females than in males. (iii) Vitamins can, on one hand, facilitate the synthesis of monoamine neurotransmitters and, on the other hand, inhibit their inactivation by competing for methylation and sulfation. Therefore, we postulate that excess multivitamin feeding in early infancy, which has become very popular over the past few decades, may be a potential risk factor for disturbed monoamine metabolism. In this paper, we will focus on the relationship between excess multivitamin exposure and the inactivation/degradation of monoamine neurotransmitters and its possible role in the development of autism.

  5. Dose-to-risk conversion factors for low-level tritium exposures

    International Nuclear Information System (INIS)

    Straume, T.

    1992-01-01

    During the past decade, a large number of radiobiological studies have become available for tritium-many of them focusing on the relative biological effectiveness (RBE) of tritium beta rays. These and previous studies indicate that tritium in body water produces the same spectrum of radiogenic effects, e.g., cancer, genetic effects, developmental abnormalities, and reproductive effects, observed following whole-body exposure to penetrating radiations such as gamma rays and x rays. The only significant difference in biological response between tritium beta-rays and the other common low linear-energy transfer (LET) radiations, such as gamma rays and x rays, appears to be the greater biological effectiveness of tritium beta rays. For example, tritium in the oxide form (HTO) is about 2 to 3 times more effective at low doses or low dose rates than gamma rays from 137 Cs or 60 CO (Straume, 1991). When tritium is bound to organic molecules, RBE values may be somewhat larger than those for HTO. It is now clear from the wealth of tritium data available that RBEs for tritium beta rays are higher than the quality factor of unity generally used in radiation protection

  6. Reproductive survival of explanted human tumor cells after exposure to nitrogen mustard or x irradiation; differences in response with subsequent subculture in vitro

    International Nuclear Information System (INIS)

    Wells, J.; Berry, R.J.; Laing, A.H.

    1977-01-01

    Curves for the survival of reproductive capacity of explanted human tumor cells, following exposure to the alkylating agent nitrogen mustard (mustine hydrochloride) or 250-kVp x rays, were obtained as soon as a satisfactory plating efficiency, i.e., greater than or approximately equal to 10 percent, was obtained from the tumor cells in vitro (usually within 2-10 weeks of explanation). It was found that all six tumor explants tested became more sensitive to the action of nitrogen mustard on serial subculture, whereas the response of four explants which were X-irradiated was invariant with further subculturing. Furthermore, all but one explant yielded survival curves which were extremely similar, with D/sub q/ values circa 440-610 rad. One line, from a seminoma, however, had a D/sub q/ of 150 rad. These radiosensitive seminoma cells were, however, the most resistant to the action of nitrogen mustard. The increase in sensitivity to nitrogen mustard with serial subculture in vitro was not associated with any change in the proliferative rate of the cells, although it may be associated with an increase in the efficiency of transport

  7. Transcription factor VdCmr1 is required for pigment production, protection from UV irradiation, and regulates expression of melanin biosynthetic genes in Verticillium dahliae.

    Science.gov (United States)

    Wang, Yonglin; Hu, Xiaoping; Fang, Yulin; Anchieta, Amy; Goldman, Polly H; Hernandez, Gustavo; Klosterman, Steven J

    2018-04-01

    Verticillium dahliae is a soilborne fungus that causes vascular wilt diseases on numerous plant species worldwide. The production of darkly melanized microsclerotia is crucial in the disease cycle of V. dahliae, as these structures allow for long-term survival in soil. Previously, transcriptomic and genomic analysis identified a cluster of genes in V. dahliae that encodes some dihydroxynaphthalene (DHN) melanin biosynthetic pathway homologues found in related fungi. In this study, we explored the roles of cluster-specific transcription factor VdCmr1, as well as two other genes within the cluster encoding a polyketide synthase (VdPKS1) and a laccase (VdLac1), enzymes at initial and endpoint steps in DHN melanin production. The results revealed that VdCmr1 and VdPKS1 are required for melanin production, but neither is required for microsclerotia production. None of the three genes were required for pathogenesis on tobacco and lettuce. Exposure of ΔVdCmr1 and wild-type strains to UV irradiation, or to high temperature (40 °C), revealed an approx. 50 % reduction of survival in the ΔVdCmr1 strain, relative to the wild-type strain, in response to either condition. Expression profiles revealed that expression of some melanin biosynthetic genes are in part dependent on VdCmr1. Combined data indicate VdCmr1 is a key regulator of melanin biosynthesis, and that via regulation of melanogenesis, VdCmr1 affects survival of V. dahliae in response to abiotic threats. We conclude with a model showing regulation of VdCmr1 by a high osmolarity glycerol response (Hog)-type MAP kinase pathway.

  8. Whole body X-irradiation and impact of dietary factors on brain and testes of albino rats

    International Nuclear Information System (INIS)

    Hasan, S.S.; Chaturvedi, P.K.

    1988-01-01

    The study was undertaken to investigate the radioprotective effect of protein diet on the irradiated brain and testes. The study indicated that the less availability of protein in the diet caused a marked reduction in the protein and nucleic acid (DNA and RNA) contents of brain after irradiation. Further, the protein deficiency in diet brought about an increased deamination of protein in the brain of irradiated rats. It was noted that in response to irradiation the testes of protein deficient diet fed rats got adversely affected as compared to high protein diet fed animals. This paper gives evidence that feeding of protein enriched diet provides protection against ionizing radiation. (orig.) [de

  9. Exposure to secondhand smoke and associated factors among non-smoking pregnant women with smoking husbands in Sichuan province, China.

    Science.gov (United States)

    Yang, Lian; Tong, Elisa K; Mao, Zhengzhong; Hu, Teh-wei

    2010-01-01

    Secondhand smoke (SHS) exposure harms pregnant women and the fetus. China has the world's largest number of smokers and a high male smoking prevalence rate. To compare exposure to SHS among rural and urban Chinese non-smoking pregnant women with smoking husbands, and analyze factors associated with the level of SHS exposure and hair nicotine concentration. Sichuan province, China. In all 1,181 non-smoking pregnant women with smoking husbands recruited from eight district/county Women and Children's hospitals. The women completed a questionnaire in April and May 2008. Based on systematic sampling, 186 pregnant women were selected for sampling the nicotine concentration in their hair. Ordinal logistic regression analysis was conducted to examine correlates with self-reported SHS exposure (total and at home); linear regression was conducted for the sub-sample of hair nicotine concentrations. Secondhand smoking exposure rates, hair nicotine levels. About 75.1% of the non-smoking pregnant women with smoking husbands reported regular SHS exposure. The major source of exposure was through their husband. In the multivariate analysis, the risk of greater SHS exposure (total and at home) and hair nicotine concentration was increased for women who were rural, had a husband with greater cigarette consumption, less knowledge about SHS, less negative attitudes about SHS, and no smoke-free home rules. The high prevalence rate of SHS exposure suggests that it is important for non-smoking pregnant women, especially rural women, to establish smoke-free home rules and increase knowledge and negative attitudes towards SHS.

  10. Surgery and Anesthesia Exposure Is Not a Risk Factor for Cognitive Impairment After Major Noncardiac Surgery and Critical Illness

    NARCIS (Netherlands)

    Hughes, Christopher G; Patel, Mayur B; Jackson, James C; Girard, Timothy D; Geevarghese, Sunil K; Norman, Brett C; Thompson, Jennifer L; Chandrasekhar, Rameela; Brummel, Nathan E; May, Addison K; Elstad, Mark R; Wasserstein, Mitzi L; Goodman, Richard B; Moons, Karel G; Dittus, Robert S; Ely, E Wesley; Pandharipande, Pratik P; MIND-ICU, BRAIN-ICU investigators

    OBJECTIVE: The aim of this study was to determine whether surgery and anesthesia exposure is an independent risk factor for cognitive impairment after major noncardiac surgery associated with critical illness. SUMMARY OF BACKGROUND DATA: Postoperative cognitive impairment is a prevalent individual

  11. A case-control study of hormonal exposures as etiologic factors for ALS in women : Euro-MOTOR

    NARCIS (Netherlands)

    Rooney, James P K; Visser, Anne E; D'Ovidio, Fabrizio; Vermeulen, Roel; Beghi, Ettore; Chio, Adriano; Veldink, Jan H.; Logroscino, Giancarlo; van den Berg, Leonard H.; Hardiman, Orla

    2017-01-01

    OBJECTIVE: To investigate the role of hormonal risk factors for amyotrophic lateral sclerosis (ALS) among women from 3 European countries. METHODS: ALS cases and matched controls were recruited over 4 years in Ireland, Italy, and the Netherlands. Hormonal exposures, including reproductive history,

  12. Cultural and Demographic Factors Influencing Noise Exposure Estimates from Use of Portable Listening Devices in an Urban Environment

    Science.gov (United States)

    Fligor, Brian J.; Levey, Sandra; Levey, Tania

    2014-01-01

    Purpose: This study examined listening levels and duration of portable listening devices (PLDs) used by people with diversity of ethnicity, education, music genre, and PLD manufacturer. The goal was to estimate participants' PLD noise exposure and identify factors influencing user behavior. Method: This study measured listening levels of 160…

  13. Prenatal nicotinic exposure suppresses fetal adrenal steroidogenesis via steroidogenic factor 1 (SF-1) deacetylation

    Energy Technology Data Exchange (ETDEWEB)

    Yan, You-e [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan (China); Liu, Lian [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan (China); Department of Pharmacology, Medical School of Yangtze University, Jingzhou 434000 (China); Wang, Jian-fei; Liu, Fang; Li, Xiao-hai; Qin, Hai-quan [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan (China); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan (China); Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan 430071 (China)

    2014-06-15

    This study aimed to investigate the suppressive effect of nicotine on fetal adrenal steroidogenesis and to explore the potential role of epigenetic modification of steroidogenic factor-1 (SF-1) transcriptional activity in this process. Nicotine was intragastrically administered to pregnant rats and NCI-H295A cells were treated with nicotine or trichostatin A (TSA). The pathomorphology of fetal adrenals, steroid hormone levels, the expression of SF-1 and its target genes, and histone deacetylase (HDAC) mRNA were analyzed. Histone modification and DNA methylation of the SF-1 promoter region were assessed using chromatin immunoprecipitation (ChIP) and bisulfite sequencing PCR. The interaction between SF1 and its target genes was observed. Prenatal nicotinic exposure decreased fetal body weight, increased the IUGR rate and caused detrimental changes in fetal adrenal. In addition, the levels of corticosterone, the expression of SF-1 and its target genes were decreased while HDAC2 expression was enhanced. Nicotine treatment decreased histone H3K9 and H3K14 acetylation levels while there was no effect on the methylation frequency on the SF-1 promoter region. Furthermore, in nicotine-treated NCI-H295A cells, lower levels of steroidogenic synthesis, lower expression of SF-1 and its target genes were observed while the expression of HDACs was enhanced. The interaction between SF1 and StAR decreased with nicotine treatment. Nicotine treatment decreased histone H3K9 and H3K14 acetylation levels, and addition of TSA reversed the inhibition of nicotine-mediated SF-1 and its partial target genes. Thus, nicotine-mediated reduction of SF-1 expression resulted in an inhibitory effect on the expression of its target genes and steroid production via histone deacetylation. - Highlights: • Prenatal nicotine-exposed suppresses fetal adrenal steroidogenesis. • Nicotine-supressed fetal adrenal steroidogenesis is related to SF-1 deacetylation. • Prenatal nicotinic exposure decreased

  14. Prenatal nicotinic exposure suppresses fetal adrenal steroidogenesis via steroidogenic factor 1 (SF-1) deacetylation

    International Nuclear Information System (INIS)

    Yan, You-e; Liu, Lian; Wang, Jian-fei; Liu, Fang; Li, Xiao-hai; Qin, Hai-quan; Wang, Hui

    2014-01-01

    This study aimed to investigate the suppressive effect of nicotine on fetal adrenal steroidogenesis and to explore the potential role of epigenetic modification of steroidogenic factor-1 (SF-1) transcriptional activity in this process. Nicotine was intragastrically administered to pregnant rats and NCI-H295A cells were treated with nicotine or trichostatin A (TSA). The pathomorphology of fetal adrenals, steroid hormone levels, the expression of SF-1 and its target genes, and histone deacetylase (HDAC) mRNA were analyzed. Histone modification and DNA methylation of the SF-1 promoter region were assessed using chromatin immunoprecipitation (ChIP) and bisulfite sequencing PCR. The interaction between SF1 and its target genes was observed. Prenatal nicotinic exposure decreased fetal body weight, increased the IUGR rate and caused detrimental changes in fetal adrenal. In addition, the levels of corticosterone, the expression of SF-1 and its target genes were decreased while HDAC2 expression was enhanced. Nicotine treatment decreased histone H3K9 and H3K14 acetylation levels while there was no effect on the methylation frequency on the SF-1 promoter region. Furthermore, in nicotine-treated NCI-H295A cells, lower levels of steroidogenic synthesis, lower expression of SF-1 and its target genes were observed while the expression of HDACs was enhanced. The interaction between SF1 and StAR decreased with nicotine treatment. Nicotine treatment decreased histone H3K9 and H3K14 acetylation levels, and addition of TSA reversed the inhibition of nicotine-mediated SF-1 and its partial target genes. Thus, nicotine-mediated reduction of SF-1 expression resulted in an inhibitory effect on the expression of its target genes and steroid production via histone deacetylation. - Highlights: • Prenatal nicotine-exposed suppresses fetal adrenal steroidogenesis. • Nicotine-supressed fetal adrenal steroidogenesis is related to SF-1 deacetylation. • Prenatal nicotinic exposure decreased

  15. Oxygen delivery in irradiated normal tissue

    Energy Technology Data Exchange (ETDEWEB)

    Kiani, M.F.; Ansari, R. [Univ. of Tennessee Health Science Center, Memphis, TN (United States). School of Biomedical Engineering; Gaber, M.W. [St. Jude Children' s Research Hospital, Memphis, TN (United States)

    2003-03-01

    Ionizing radiation exposure significantly alters the structure and function of microvascular networks, which regulate delivery of oxygen to tissue. In this study we use a hamster cremaster muscle model to study changes in microvascular network parameters and use a mathematical model to study the effects of these observed structural and microhemodynamic changes in microvascular networks on oxygen delivery to the tissue. Our experimental observations indicate that in microvascular networks while some parameters are significantly affected by irradiation (e.g. red blood cell (RBC) transit time), others remain at the control level (e.g. RBC path length) up to 180 days post-irradiation. The results from our mathematical model indicate that tissue oxygenation patterns are significantly different in irradiated normal tissue as compared to age-matched controls and the differences are apparent as early as 3 days post irradiation. However, oxygen delivery to irradiate